JP7748478B2 - Terminal, wireless communication method, base station and system - Google Patents

Description

The present disclosure relates to a terminal, a wireless communication method , a base station , and a system in a next-generation mobile communication system.

Long Term Evolution (LTE) was specified for Universal Mobile Telecommunications System (UMTS) networks with the aim of achieving even higher data rates and lower latency (Non-Patent Document 1). Furthermore, LTE-Advanced (3GPP Rel. 10-14) was specified with the aim of achieving even higher capacity and more advanced features than LTE (Third Generation Partnership Project (3GPP) Release (Rel.) 8, 9).

Successor systems to LTE (also known as 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 or later, etc.) are also being considered.

3GPP TS 36.300 V8.12.0 “Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN); Overall description; Stage 2 (Release 8)”, April 2010

With regard to future wireless communication technologies, the use of artificial intelligence (AI) technologies such as machine learning (ML) for network/device control and management is being considered. For example, the use of AI/ML complementation to reduce reference signal (RS) resources is being considered.

However, the specifics of the RS resource reduction have not yet been fully explored. Unless these are properly defined, highly efficient resource utilization cannot be achieved, and there is a risk that improvements in communication throughput or communication quality may be hindered.

Therefore, one of the objects of the present disclosure is to provide a terminal, a wireless communication method , a base station , and a system that can realize suitable use of RS resources.

A terminal according to one aspect of the present disclosure has one or more reference signal settings, a receiving unit that receives information related to the reference signals, and a control unit that determines an application period of the information related to the reference signals and determines mapping of the reference signals based on the reference signal settings and the information related to the reference signals, and when the reference signals are reference signals for channels that are scheduled across multiple slots, the control unit applies the information related to the reference signals to all of the channels .

One aspect of the present disclosure enables the use of suitable RS resources.

FIG. 1 is a diagram illustrating an example of setting a reference signal according to option 1-1 of the first embodiment. FIG. 2 is a diagram illustrating an example of setting of a reference signal according to option 1-2 of the first embodiment. FIG. 3 is a diagram illustrating an example of conditions related to a reference signal according to the first embodiment. 4A and 4B are diagrams showing an example of sampling of a reference signal. 5A and 5B are diagrams illustrating an example of mapping of reference signals according to the second embodiment. FIG. 6 is a diagram showing another example of mapping of reference signals according to the second embodiment. 7A and 7B are diagrams illustrating an example of mapping of reference signals according to option 2-2-1 of the second embodiment. FIG. 8 is a diagram illustrating an example of mapping of reference signals according to option 2-2-2 of the second embodiment. 9A and 9B are diagrams showing an example of determining a group according to option 2-3-2 of the second embodiment. 10A and 10B are diagrams illustrating an example of application of information related to a reference signal according to option 4-1 of the fourth embodiment. 11A and 11B are diagrams illustrating an example of application of information related to a reference signal according to option 4-2 of the fourth embodiment. FIG. 12 is a diagram illustrating an example of overlapping of reference signals according to the fifth embodiment. FIG. 13 is a diagram illustrating an example of determining the PDSCH decoding time according to option 6-2 of the sixth embodiment. FIG. 14 is a diagram illustrating an example of the bit width of the MAC CE/DCI field according to option 7-1 of the seventh embodiment. FIG. 15 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. FIG. 16 is a diagram illustrating an example of the configuration of a base station according to an embodiment. FIG. 17 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. FIG. 18 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. FIG. 19 is a diagram illustrating an example of a vehicle according to an embodiment.

(Application of Artificial Intelligence (AI) technology to wireless communications)
Regarding future wireless communication technologies, the use of AI technology for network/device control and management is being considered.

For example, in future wireless communication technologies, particularly in communications using beams, there is a demand for high accuracy in channel estimation (also called channel measurement) for beam management, decoding of received signals, etc.

Channel estimation may be performed using at least one of, for example, a Channel State Information Reference Signal (CSI-RS), a Synchronization Signal (SS), a Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block, a Demodulation Reference Signal (DMRS), or a Sounding Reference Signal (SRS).

Regarding future wireless communication technologies, it is being considered to utilize artificial intelligence (AI) technologies such as machine learning (ML) for network/device control and management.

For example, it is being considered to use AI/ML complementation to reduce reference signal (RS) resources while maintaining channel estimation accuracy.

For example, if learning using AI/ML has not been performed (completed) in a terminal (user terminal, also referred to as User Equipment (UE))/base station, the following requirements may be necessary to achieve RS reception measurements that enable high channel estimation accuracy or accurate RS reception measurements used for learning:
- Transmitting and receiving RS in a wide band (contributing to improved reception quality);
Repeatedly transmitting RS to combine received channels/signals (combined reception) on the receiving side (contributing to improved reception quality);
High time/frequency density of RS resources (helps to obtain good time/frequency correlation).

Taking these factors into consideration, it is believed that the appropriate allocation of RSs will differ depending on whether AI/ML has been sufficiently trained or not. Therefore, it is desirable to introduce a method and framework for dynamically allocating appropriate RS resources.

However, the specific content of this framework has yet to be fully explored. Unless these are properly defined, highly efficient resource utilization cannot be achieved, and there is a risk that improvements in communication throughput or communication quality may be hindered.

In addition, in the existing specifications (up to Rel. 16), the mapping of reference signals (DMRS/PTRS) is specified to be set at the following granularity:
- Each configured grant PUSCH.
- For each DCI format (DCI format 0_1/0_2/1_1/1_2).
For each PUSCH/PDSCH mapping type A or B.
- Whether it is a PUSCH that transmits message A (Msg. A PUSCH).

In order to achieve highly efficient resource utilization as described above, it is desirable to introduce more flexible and dynamic reference signal mapping settings.

The inventors have therefore come up with a suitable method for allocating/utilizing RS resources.

Note that each embodiment of the present disclosure may be applied when AI/ML/prediction is not used. In this case, it is possible to change RS settings with reduced delay/overhead without RRC reconfiguration.

In one embodiment of the present disclosure, a UE/BS trains an ML model in a training mode and executes the ML model in a test mode (also referred to as a test mode, etc.). In the test mode, the accuracy of the trained ML model may be validated.

In the present disclosure, the UE/BS may input channel state information, reference signal measurements, etc. into the ML model and output highly accurate channel state information/measurements/beam selection/position, future channel state information/radio link quality, etc.

In the present disclosure, AI may be interpreted as an object (also referred to as a subject, object, data, function, program, etc.) having (implementing) at least one of the following characteristics:
- Estimation based on observed or collected information;
- selections based on observed or collected information;
- Predictions based on observed or collected information.

In the present disclosure, the object may be, for example, an apparatus or device such as a terminal or base station. The object may also correspond to a program included in the apparatus.

In addition, in the present disclosure, an ML model may be interpreted as an object having (implementing) at least one of the following characteristics:
- Producing estimates by feeding information,
- Predicting estimates by providing information
- Discover features by providing information,
-Select an action by providing information.

In the present disclosure, the term "ML model" may be interpreted as at least one of an AI model, predictive analytics, a predictive analysis model, etc. The ML model may also be derived using at least one of regression analysis (e.g., linear regression analysis, multiple regression analysis, logistic regression analysis), a support vector machine, a random forest, a neural network, deep learning, etc. In the present disclosure, the term "model" may be interpreted as at least one of an encoder, a decoder, a tool, etc.

Based on the input information, the ML model outputs at least one piece of information, such as an estimate, a prediction, a selected action, or a classification.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. The wireless communication methods according to the embodiments may be applied independently or in combination.

In the following embodiments, to explain the ML model for communication between a UE and a BS, the relevant entities are a UE and a BS, but the application of each embodiment of the present disclosure is not limited to this. For example, for communication between other entities (e.g., communication between UEs), the UE and BS in the following embodiments may be replaced with a first UE and a second UE. In other words, the UE, BS, etc. in the present disclosure may all be replaced with any UE/BS.

In this disclosure, "A/B" and "at least one of A and B" may be read interchangeably.

In this disclosure, terms such as activate, deactivate, indicate, select, configure, update, and determine may be read interchangeably. In this disclosure, terms such as support, control, controllable, operate, and operable may be read interchangeably.

In the present disclosure, the terms Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, information elements (IEs), and configurations may be interchangeable. In the present disclosure, the terms Medium Access Control (MAC) Control Element (CE), update commands, and activation/deactivation commands may be interchangeable.

In the present disclosure, the terms panel, UE panel, panel group, beam, beam group, precoder, uplink (UL) transmitting entity, TRP, spatial relationship information (SRI), spatial relationship, SRS resource indicator (SRI), SRS resource, control resource set (CONTROLLER RESOLUTION SET (CORESET)), Physical Downlink Shared Channel (PDSCH), codeword, base station, reference signal, predetermined antenna port (e.g., demodulation reference signal (DMRS) port), predetermined antenna port group (e.g., DMRS port group), predetermined group (e.g., code division multiplexing (CDM) group, predetermined reference signal group, CORESET group), predetermined resource (e.g., predetermined reference signal resource), predetermined resource set (e.g., predetermined reference signal resource set), CORESET pool, PUCCH group (PUCCH resource group), spatial relationship group, downlink Transmission Configuration Indication The terms "TCI state" (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, quasi-co-location (QCL), QCL assumption, etc. may be read as interchangeable terms.

In this disclosure, the terms index, ID, indicator, and resource ID may be interchangeable. In this disclosure, the terms sequence, list, set, group, cluster, subset, etc. may be interchangeable.

In the present disclosure, beam report may be interchangeably referred to as beam measurement report, CSI report, CSI measurement report, predicted beam report, predicted CSI report, etc.

In the present disclosure, CSI-RS may be interchangeably read as at least one of non-zero power (NZP) CSI-RS, zero power (ZP) CSI-RS, and CSI interference measurement (CSI-IM).

In this disclosure, the measured/reported RS may refer to the RS measured/reported for beam reporting.

In this disclosure, timing, time, duration, slot, subslot, symbol, subframe, etc. may be interpreted interchangeably.

In this disclosure, terms such as direction, axis, dimension, polarization, and polarization component may be interchangeable.

In this disclosure, estimation, prediction, and inference may be interpreted interchangeably. In this disclosure, estimate, predict, and infer may be interpreted interchangeably.

In the present disclosure, the RS may be, for example, a CSI-RS, an SS/PBCH block (SS block (SSB)), etc. Furthermore, the RS index may be a CSI-RS resource indicator (CSI-RS Resource Indicator (CRI)), an SS/PBCH block resource indicator (SS/PBCH Block Indicator (SSBRI)), etc.

In the present disclosure, CSI feedback, CSI feedback information, CSI report, CSI report, CSI transmission, CSI information, CSI, etc. may be read interchangeably.

In addition, in the present disclosure, subband may be interchangeably referred to as physical resource block (PRB), subcarrier, any frequency resource unit, etc.

(Wireless communication method)
The (specific) reference signal described in each embodiment of the present disclosure may be at least one of a demodulation reference signal (DMRS), a phase tracking reference signal (PTRS), or any other reference signal described in the present disclosure. In the present disclosure, the terms "reference signal,""DMRS,""PTRS," and any other reference signal described in the present disclosure may be interchangeable.

The reference signal described in each embodiment of the present disclosure may be a UL reference signal (a reference signal for the UL channel) or a DL reference signal (a reference signal for the DL channel).

In the following embodiments of the present disclosure, DMRS will be mainly described as an example, but the reference signal is not limited to DMRS and can be applied to any reference signal.

In the present disclosure, the terms "assigning," "mapping," "transmitting," and "receiving" a reference signal may be interpreted interchangeably.

First Embodiment
In the first embodiment, a method for determining the mapping of reference signals will be described.

The UE may determine the reference signal mapping according to at least one of the following options 1-1 to 1-3.

Option 1-1
The UE may determine/select one reference signal configuration from multiple configurations for reference signals.

The determination/selection of the one reference signal setting may be based on specific conditions/instructions from the base station. Specific conditions/instructions from the base station will be described in more detail below.

For example, the UE may determine/select one reference signal setting (reference signal setting X or reference signal setting Y) from multiple reference signal settings (reference signal setting X and reference signal setting Y) at least when transmitting an UL channel (e.g., PUSCH) and when receiving a DL channel (e.g., PDSCH).

Note that the number of multiple reference signal settings may be two as described above, or may be two or more. In the present disclosure, reference signal setting X may be interchangeably read as the first reference signal setting, and reference signal setting Y may be interchangeably read as the second reference signal setting.

The UE may determine that one reference signal configuration among multiple reference signal configurations is the default reference signal configuration.

In the present disclosure, default reference signal setting may mean the setting that the UE selects/determines when it does not receive a signal from the base station (network) specifying/instructing the selection/determination.

The multiple reference signal settings (reference signal setting X and reference signal setting Y) may correspond to, for example, at least one of the uplink setting of the demodulation reference signal (DMRS) (e.g., the upper layer parameter "DMRS-UplinkConfig") and the downlink setting of the demodulation reference signal (DMRS) (e.g., the upper layer parameter "DMRS-DownlinkConfig").

The multiple reference signal configuration may be a configuration that includes at least one of the following elements/parameters:
- Type of reference signal (e.g., DMRS) configuration.
Number of Code Division Multiplexing (CDM) groups (not used for data).
Number of symbols for additional DMRS.
Maximum number of OFDM symbols for front loaded DMRS.
Frequency resources (e.g., subcarriers) on which to transmit the reference signal.
The symbol position of the first DMRS (e.g., starting DMRS) for a particular mapping type (e.g., mapping type A).
- Frequency density/time density of PTRS.
- Frequency (e.g. subcarrier) offset of the PTRS.
Energy per resource element (EPRE) ratio between PTRS and DL channel (e.g., PDSCH).
- PTRS transmission power boosting factor.

Figure 1 is a diagram showing an example of reference signal configuration related to option 1-1 of the first embodiment. In Figure 1, the UE selects/determines one reference signal configuration from multiple reference signal configurations (DMRS configuration X and DMRS configuration Y) based on specific conditions/instructions from the base station.

In the example shown in Figure 1, DMRS setting X does not include PTRS settings (at least one of elements/parameters related to PTRS, for example, frequency density/time density of PTRS, frequency (e.g., subcarrier) offset of PTRS, EPRE ratio between PTRS and DL channel (e.g., PDSCH), and transmit power boosting factor of PTRS), while DMRS setting Y includes at least one PTRS setting. Note that whether or not a PTRS setting is included in the settings of multiple reference signals may be optional.

In the example shown in Figure 1, the UE selects/decides one DMRS setting (DMRS setting X) based on specific conditions/instructions from the base station.

<<Option 1-2>>
The UE may change/update some/all of the settings of one reference signal configuration based on specific conditions/instructions from the base station.

For example, the UE may change/update the mapping type of the reference signal of an already selected/configured reference signal setting (DMRS setting) and apply it to at least one of transmitting an UL channel (e.g., PUSCH) and receiving a DL channel (e.g., PDSCH).

Also, for example, the settings to be changed/updated may be settings that include at least one of the following elements/parameters:
- Type of reference signal (e.g., DMRS) configuration.
Number of Code Division Multiplexing (CDM) groups (not used for data).
Number of symbols for additional DMRS.
Maximum number of OFDM symbols for front loaded DMRS.
Frequency resources (e.g., subcarriers) on which to transmit the reference signal.
The symbol position of the first DMRS (e.g., starting DMRS) for a particular mapping type (e.g., mapping type A).
- Frequency density/time density of PTRS.
- Frequency (e.g. subcarrier) offset of the PTRS.
EPRE ratio of PTRS to DL channel (e.g. PDSCH).
- PTRS transmission power boosting factor.

Figure 2 is a diagram showing an example of reference signal configuration related to option 1-2 of the first embodiment. In Figure 2, the UE changes some/all of the reference signal configuration from the already configured/selected reference signal configuration (DMRS configuration X) based on specific conditions/instructions from the base station.

In the example shown in Figure 2, for example, the UE receives information from the base station instructing it to change the number of additional DMRS symbols. At this time, the UE changes the number of DMRS (additional DMRS) symbols based on the information.

In the example shown in Figure 2, for example, the UE receives information from the base station instructing it to change the maximum number of OFDM symbols for frontloaded DMRS. At this time, the UE changes the number of symbols for DMRS (additional DMRS) based on the information.

<<Options 1-3>>
The above options 1-1 and 1-2 may be applied in combination.

For example, the UE may first use option 1-1 to select/determine one reference signal configuration for a certain channel. Then, the UE may use option 1-2 to change/update the reference signal configuration for that channel.

Also, for example, the UE may first use option 1-1 to select/determine one reference signal setting for a certain channel (first channel). Then, the UE may use option 1-2 to change/update the reference signal setting for the first channel. Furthermore, the UE may use option 1-1 to select/determine one reference signal setting for a channel (second channel) different from the first channel. Then, the UE may use option 1-2 to change/update the reference signal setting for the second channel.

In this way, when reference signal settings are selected/determined/changed/updated for multiple different channels, the UE may ignore the setting/change of the first channel.

Furthermore, when reference signal settings are selected/determined/changed/updated for multiple different channels in this manner, the UE may maintain the setting/change of the first channel.

The following explains the specific conditions/instructions from the base station.

The UE may receive instruction information regarding reference signal mapping from the base station (network).

Instruction information regarding reference signal mapping may be received based on the method described in the third embodiment below.

The instruction information regarding the mapping of the reference signal may be information regarding the reference signal described in the second embodiment below.

The UE may judge/decide on the mapping of the reference signal based on whether certain conditions are met at least one of when transmitting an UL channel (e.g., PUSCH) and when receiving a DL channel (e.g., PDSCH).

The specific conditions may be determined based on specific rules. The specific conditions may also be determined based on information received according to the method described in the third embodiment below.

The UE may at least one of determine the mapping of reference signals to apply and decide whether to apply information about the received reference signals based on whether certain conditions are met when transmitting an UL channel (e.g., PUSCH) and/or when receiving a DL channel (e.g., PDSCH).

For example, the UE may determine to apply a specific reference signal configuration when certain conditions are met. Also, the UE may determine to apply information related to the received reference signal when certain conditions are met.

On the other hand, if certain conditions are not met, the UE may apply reference signal configuration based on a specific method. The specific method may be a reference signal configuration method specified in existing specifications (e.g., Rel. 15/16). The specific method may also be the default configuration in Option 1-1 above. The specific method may also be the (default) configuration to which the changes (instructions) in Option 1-2 above are not applied.

The specific condition may be at least one of the following conditions:
Whether reference signal bundling (e.g. DMRS bundling) is applied or not.
Whether or not at least one of transmission of a UL channel (e.g., PUSCH) and reception of a DL channel (e.g., PDSCH) is performed across multiple time resources (e.g., slots).
Whether or not the resource (e.g., RE) for receiving the configured CSI-RS overlaps with the mapping resource of the reference signal based on the received information.
Modulation order (for UL/DL channels).
Number of layers (for UL/DL channels).
Number of DMRS ports (for UL/DL channels).
DCI format for allocating (scheduling/activating) UL channels (e.g., PUSCH)/DL channels (e.g., PDSCH).
Whether it is a specific UL channel/DL channel.
A Radio Network Temporary Identifier (RNTI) that scrambles the Cyclic Redundancy Check (CRC) of the DCI that schedules/activates the UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH).
- Per configured grant configuration index (CofiguredGrantConfigIndex).
-Whether or not the DCI that allocates (schedules/activates) a UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH) includes information about reference signals.
The state of the UE corresponding to the learning state or the state after learning.
UE speed/UE speed direction.

By making the decision based on whether DMRS bundling is applied or not, DMRS bundling improves/improves channel estimation accuracy, making it possible to maintain estimation accuracy even if the number of DMRS symbols is reduced.

In this disclosure, "DMRS bundling" may mean transmitting (e.g., one) DMRS with equal power and while maintaining phase continuity across multiple time resources (e.g., slots). In this disclosure, DMRS bundling, cross-slot channel estimation, cross-repetition channel estimation, and using a common DMRS across multiple time resources may be interchangeable.

UL channels/DL channels spanning multiple time resources (e.g., slots) may, for example, be at least one of repetition and transport block (TB) processing over multi-slots (TBoMS).

The overlap between the resources (e.g., REs) for receiving the configured CSI-RS and the mapping resources for the reference signal based on the received information is described in detail in the fifth embodiment below.

For a specific DCI format (e.g., DCI format 0_0/1_0) to which a UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH) is assigned (scheduled/activated), information related to reference signals (information related to reference signal mapping) may be omitted. This allows a configuration in which dynamic reference signal mapping is not applied to the specific DCI format.

The above-mentioned specific UL channel/DL channel may be, for example, at least one of a PUSH of message A (e.g., message A) for a random access procedure of a specific type (e.g., type 2), a configured grant (type 1/2) PUSH, a semi-persistent scheduling (SPS) PDSCH, and a PUSH/PDSCH scheduled/activated by DCI.

The RNTI may be, for example, at least one of a Cell (C-) RNTI, a Configured Scheduling (CS-) RNTI, a Modulcation Coding Scheme Cell (MCS-C-) RNTI, and any other RNTI.

When applying information regarding the corresponding reference signal for each configured grant setting index (ConfiguredGrantConfigIndex), the DCI/MAC CE containing information regarding the reference signal may include the index of the configured grant to be applied (Configured Grant Setting Index).

The case where the DCI allocating (scheduling/activating) a UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH) includes information regarding reference signals is described in detail in the fourth embodiment below.

The UE speed/UE direction of speed may be based, for example, on whether the UE has been identified as belonging to a specific moving body (e.g., a car, a train). The UE speed/UE direction of speed/identification may be determined by the UE (e.g., based on a sensor possessed by the UE), or may be determined based on information regarding the UE speed/UE direction of speed/identification notified by the base station.

The specific conditions may be a combination of at least two of the multiple examples of the specific conditions listed above.

For example, the UE may apply information regarding reference signals contained in the DCI/MAC CE if certain conditions are met.

In addition, if certain conditions are met, the UE may change/update some or all of the settings of one reference signal configuration based on information regarding the reference signal contained in the DCI/MAC CE.

Figure 3 is a diagram showing an example of conditions related to reference signals in the first embodiment. In the example shown in Figure 3, the UE makes a decision based on whether DMRS bundling is applied.

In Figure 3, if the UE determines that DMRS bundling is applied, it determines whether multiple slots of PUSCH transmission opportunities are configured/instructed for a 1TB allocation. If the UE determines that DMRS bundling is not applied, it determines that DMRS setting A is to be applied.

In Figure 3, if the UE determines that multiple slots of PUSCH transmission opportunities are configured/instructed for a 1TB allocation, it determines to apply DMRS setting B. If the UE determines that multiple slots of PUSCH transmission opportunities are not configured/instructed for a 1TB allocation, it determines to apply DMRS setting A.

Note that these DMRS settings A and B are merely examples, and the setting names and number of settings are not limited to these.

According to the first embodiment described above, it is possible to appropriately select/determine/change/update the mapping of reference signals.

Second Embodiment
In the second embodiment, information related to a reference signal will be described.

The UE may receive information regarding reference signals from the base station (network).

The information regarding the reference signal may include an index of the reference signal configuration to apply to the reference signal mapping.

The index of the reference signal configuration to be applied to the mapping of the reference signal may be an index indicating one reference signal configuration to be applied from among multiple reference signal configurations set.

If the UE does not receive information about a reference signal including the index of the reference signal configuration, the UE may apply a default reference signal configuration. The default reference signal may be determined by a specific rule or based on the RRC signaling configuration.

The information about the reference signal may include parameters for setting the reference signal, which may be at least one of the following parameters:
- Type of reference signal (e.g., DMRS) configuration.
Number of Code Division Multiplexing (CDM) groups (not used for data).
Number of symbols for additional DMRS.
Maximum number of OFDM symbols for front loaded DMRS.
Frequency resources (e.g., subcarriers) on which to transmit the reference signal.
The symbol position of the first DMRS (e.g., starting DMRS) for a particular mapping type (e.g., mapping type A).
- Frequency density/time density of PTRS.
- Frequency (e.g. subcarrier) offset of the PTRS.
Energy per resource element (EPRE) ratio between PTRS and DL channel (e.g., PDSCH).
- PTRS transmission power boosting factor.
Number of DMRS combs at RE level (per RE)/resource block (RB) level (per RB).
The number of samples/sampling interval/sampling offset when sampling the reference signal symbols.
The number of samples/sampling interval/sampling offset when sampling the subcarriers of the reference signal.
- Index associated with number of samples/sampling interval/sampling offset.

The sampling offset may be an offset value for determining the symbol at which sampling starts.The sampling offset may be an offset value for determining the subcarrier at which sampling starts.

In this disclosure, sampling a reference signal may also mean determining/changing the symbols/subcarriers to which the reference signal is/is not mapped.

Figures 4A and 4B show examples of sampling of a reference signal. Figure 4A shows the case where the sampling interval is 2 and the sampling offset is 0. Figure 4B shows the case where the sampling interval is 2 and the sampling offset is 1.

In the examples shown in Figures 4A and 4B, the UE determines the DMRS symbol based on the indicated sampling interval and offset.

The information regarding the reference signal may include information regarding time resources to which the reference signal is not mapped. The information regarding time resources to which the reference signal is not mapped may be determined according to at least one of options 2-1-1 to 2-1-3 below.

Option 2-1-1
The information regarding the time resource to which the reference signal is not mapped may be information indicating the symbol to which the reference signal is not mapped.

The information indicating the symbols to which the reference signal is not mapped may be a bitmap.

The UE may determine the symbols to which the reference signal is not mapped based on information (bitmap) indicating the symbols to which the reference signal is not mapped.

The UE may assume (expect)/determine that no reference signal is mapped in the (OFDM) symbol where the indicated bitmap value corresponds to a bit with a first value (e.g., 1 (or 0)).

Each bit (value) in the bitmap may correspond to one or more symbols. Each bit (value) in the bitmap may correspond to X symbols (X is an integer greater than or equal to 1). X may be specified in advance in a specification, may be determined based on a specific rule, may be set by RRC signaling, or may be determined based on reported UE capability information.

The length (bit length) of the bitmap may be specified in advance in a specification, may be determined based on specific rules, may be set by RRC signaling, or may be determined based on reporting of UE capability information.

The length of the bitmap may be determined based on the number of reference signal symbols in N slots (N is an integer, e.g., N=1)/repetition. For example, the length of the bitmap may be the number of reference signal symbols in N slots/repetition.

The length of the bitmap may be determined based on the number of symbols of the additional reference signal (e.g., additional DMRS) plus M (M is an integer, e.g., M = 1). For example, the length of the bitmap may be the number of symbols of the additional reference signal (e.g., additional DMRS) plus M.

The length of the bitmap may be determined based on the number of allocated symbols for the UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH). For example, the length of the bitmap may be the number of allocated symbols for the UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH).

When repeated transmission/TBoMS is applied to an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH), the length of the bitmap may be determined based on a value obtained by multiplying at least one of the following: the number of reference signal symbols in N slots/repeated transmissions, the number of additional reference signal symbols plus M, and the number of allocated symbols for the UL channel/DL channel, by the number of repetitions/number of allocated slots. For example, when repeated transmission/TBoMS is applied to an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH), the length of the bitmap may be a value obtained by multiplying at least one of the following: the number of reference signal symbols in N slots/repeated transmissions, the number of additional reference signal symbols plus M, and the number of allocated symbols for the UL channel/DL channel, by the number of repetitions/number of allocated slots.

When repeated transmission/TBoMS is applied to an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH), the length of the bitmap may be determined based on at least one of the following: the number of reference signal symbols in N slots/repeated transmissions in each slot, the number of additional reference signal symbols plus M, and the number of allocated symbols for the UL channel/DL channel. For example, when repeated transmission/TBoMS is applied to an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH), the length of the bitmap may be determined based on at least one of the following: the number of reference signal symbols in N slots/repeated transmissions in each slot, the number of additional reference signal symbols plus M, and the number of allocated symbols for the UL channel/DL channel.

The length of the bitmap may be determined based on the number of repetitions in the allocatable slots based on the RRC parameters. For example, the length of the bitmap may be the number of repetitions in the allocatable slots based on the RRC parameters.

When each bit (value) of the bitmap corresponds to multiple (X) symbols, the length of the bitmap may be determined based on the value obtained by multiplying at least one of the following: the number of reference signal symbols in N slots/repeated transmissions, the number of additional reference signal symbols plus M, and the number of assigned symbols for the UL channel/DL channel, by 1/X and rounding up the result. For example, when each bit (value) of the bitmap corresponds to multiple (X) symbols, the length of the bitmap may be the value obtained by multiplying at least one of the following: the number of reference signal symbols in N slots/repeated transmissions, the number of additional reference signal symbols plus M, and the number of assigned symbols for the UL channel/DL channel, by 1/X and rounding up the result.

The UE may receive an index associated with the bitmap based on RRC signaling/specific rules using DCI/MAC CE.

Figures 5A and 5B are diagrams showing an example of reference signal mapping for the second embodiment.

In the example shown in Figure 5A, a bitmap with a bit length equal to the number of symbols in the reference signal (DMRS) in one slot is instructed to the UE. The example shown in Figure 5A describes a case where the number of repeated transmissions is 2 and the number of symbols (X above) corresponding to each bit of the bitmap is 2.

As shown in Figure 5A, when the bitmap is instructed to the UE as "0110", the UE determines that a DMRS is mapped to the OFDM symbol for DMRS corresponding to 0, and that a DMRS is not mapped to the OFDM symbol for DMRS corresponding to 1.

In the example shown in Figure 5B, the bitmap instructed to the UE shows the case applied to each slot. In the example shown in Figure 5B, as in Figure 5A, the number of repeated transmissions is 2, and the number of symbols (X above) corresponding to each bit of the bitmap is 2.

As shown in Figure 5B, as in Figure 5A, when a bitmap of "01" is instructed to the UE, the UE determines that in each slot, DMRS is mapped to the OFDM symbol for DMRS corresponding to 0, and DMRS is not mapped to the OFDM symbol for DMRS corresponding to 1.

Option 2-1-2
The information regarding the time resource to which the reference signal is not mapped may be information indicating a slot to which the reference signal is not mapped.

The information indicating the slots to which the reference signal is not mapped may be a bitmap.

The UE may determine the slots to which the reference signal is not mapped based on information (bitmap) indicating the slots to which the reference signal is not mapped.

The UE may assume (expect)/determine that no reference signal is mapped in a slot where the indicated bitmap value corresponds to a bit with a first value (e.g., 1 (or 0)).

Each bit (value) in the bitmap may correspond to one or more slots. Each bit (value) in the bitmap may correspond to X slots (X is an integer greater than or equal to 1). X may be pre-defined in a specification, determined based on a specific rule, set by RRC signaling, or determined based on reported UE capability information.

The length (bit length) of the bitmap may be specified in advance in a specification, may be determined based on specific rules, may be set by RRC signaling, or may be determined based on reporting of UE capability information.

The length of the bitmap may be determined based on the number of repetitions when repeated transmission is applied to the UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH). For example, the length of the bitmap may be the number of repetitions when repeated transmission is applied to the UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH).

The length of the bitmap may be determined based on the number of allocated slots when TBoMS is applied to an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH). For example, the length of the bitmap may be the number of allocated slots when TBoMS is applied to an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH).

The length of the bitmap may be determined based on the number of repetitions in the allocatable slots based on the RRC parameters. For example, the length of the bitmap may be the number of repetitions in the allocatable slots based on the RRC parameters.

The length of the bitmap may be determined based on the maximum number of repetitions/number of allocated slots set in RRC signaling. For example, the length of the bitmap may be the maximum number of repetitions/number of allocated slots set in RRC signaling. In this case, the length of the bitmap can be determined independently of the content of the DCI.

When each bit (value) of the bitmap corresponds to multiple (X) slots, the length of the bitmap may be determined based on the value obtained by multiplying at least one of the number of repetitions, the number of assigned slots, the number of repetitions in assignable slots based on RRC parameters, and the maximum number of repetitions/number of assigned slots set by RRC signaling by 1/X, and rounding up the result. For example, when each bit (value) of the bitmap corresponds to multiple (X) symbols, the length of the bitmap may be determined based on the value obtained by multiplying at least one of the number of repetitions, the number of assigned slots, the number of repetitions in assignable slots based on RRC parameters, and the maximum number of repetitions/number of assigned slots set by RRC signaling by 1/X, and rounding up the result.

The UE may receive an index associated with the bitmap based on RRC signaling/specific rules using DCI/MAC CE.

Figure 6 is a diagram showing another example of reference signal mapping for the second embodiment.

In the example shown in Figure 6, the number of repeated transmissions is 4, and the number of slots corresponding to each bit in the bitmap (X above) is 2.

As shown in Figure 6, when "01" is instructed as a bitmap to a UE, the UE determines that DMRS is mapped to slots corresponding to 0 and that DMRS is not mapped to slots corresponding to 1. In the example of Figure 6, DMRS is mapped to the first two slots and DMRS is not mapped to the following two slots.

Option 2-1-3
The above options 2-1-1 and 2-1-2 may be applied in combination.

The above options 2-1-1 to 2-1-3 make it possible to appropriately determine the time resources on which reference signals are transmitted.

Information regarding reference signals may include information regarding frequency resources to which the reference signals are not mapped.

The information regarding frequency resources to which reference signals are not mapped may also be information indicating subcarriers to which reference signals are not mapped.

Information regarding frequency resources (e.g., subcarriers) to which reference signals are not mapped may be determined according to at least one of options 2-2-1 to 2-2-3 below.

Option 2-2-1
The information regarding subcarriers to which reference signals are not mapped may be information based on information that specifies (limits) the value of a sequence corresponding to a frequency resource of the reference signal.

The sequence may be an Orthogonal Cover Code (OCC) sequence (eg, w _f (k′) and/or w _t (k′)).

The value of the series (e.g., the value designated (limited) as k') may be a first value (e.g., "0") or a second value (e.g., "1").

When the value of the sequence (k') is limited to one value (the first value or the second value), the UE may determine the mapping of the reference signal based on a mathematical formula for the reference signal sequence given in Equation 1 below.

Here, α _k,l ^{(p, μ)} in the above equation 1 is the complex value of RE(k, l) corresponding to antenna port p and subcarrier spacing setting μ. Also, β _PDSCH ^DMRS is the scaling factor of the reference signal, w _f is the OCC sequence in the frequency direction, w _t is the OCC sequence in the time direction, and r is the reference signal sequence. k is the subcarrier index, l is the symbol index, and Δ is the offset value.

The above formula 1 differs from the formula defined in the existing specifications (up to Rel. 16) in that the only variable in the sequence r is n. By using the above formula 1 for mapping the reference signal, the sequence values can be used as continuous values even when k' is limited.

When the value of the sequence (k') is limited to one value (the first value or the second value), the UE may determine the mapping of the reference signal based on a mathematical formula for the reference signal sequence given in Equation 2 below.

The above equation 2 is the same as the equation for mapping reference signals (DMRS of PDSCH) specified in existing specifications (up to Rel. 16). Each parameter in equation 2 is the same as equation 1.

Note that the above Equations 1 and 2 may be applied as appropriate not only to DL channels (e.g., PDSCH) but also to UL channels (e.g., PUSCH). For example, when applying the above Equations 1 and 2 to PUSCH, the parameters for PDSCH may be appropriately changed and applied to PUSCH.

A UE may assume that reference signals are not multiplexed between UEs if the possible values of the sequence (k') differ between UEs.

The UE may determine the possible values of the sequence value (k') based on the DMRS port.

Figures 7A and 7B are diagrams showing an example of mapping of a reference signal according to option 2-2-1 of the second embodiment. When a UE receives information based on information specifying (limiting) the value of a sequence corresponding to a frequency resource of a reference signal, the UE performs mapping of the reference signal as shown in Figures 7A and 7B.

For example, the reference signal mapping shown in Figure 7A corresponds to the case of configuration type 1 and offset (Δ) = 0 in Equation 1 above. The UE determines the reference signal mapping corresponding to the cases when the value of k' is limited to 0 and when the value of k' is limited to 1.

For example, the reference signal mapping shown in Figure 7B corresponds to the case of configuration type 2 and offset (Δ) = 0 in Equation 2 above. The UE determines the reference signal mapping corresponding to the cases when the value of k' is limited to 0 and when the value of k' is limited to 1.

Option 2-2-2
The information regarding frequency resources to which reference signals are not mapped may be information indicating subcarriers to which reference signals are/are not mapped.

The information indicating the subcarriers to which the reference signal is/is not mapped may be a bitmap.

The UE may determine which subcarriers the reference signal is mapped to/not mapped to based on information (bitmap) indicating which subcarriers the reference signal is mapped to/not mapped to.

The UE may assume (expect)/determine that no reference signal is mapped to a subcarrier whose indicated bitmap value corresponds to a bit with a first value (e.g., 0 (or 1)).

Each bit (value) in the bitmap may correspond to one or more subcarriers. Each bit (value) in the bitmap may correspond to X subcarriers (X is an integer greater than or equal to 1). X may be specified in advance in a specification, may be determined based on a specific rule, may be set by RRC signaling, or may be determined based on reported UE capability information.

Each bit (value) of the bitmap may correspond to variable n in at least one of equations 1 and 2 above.

The length of the bitmap may be specified in advance, determined based on specific rules, configured by RRC signaling, or determined based on reporting of UE capability information.

For example, the length of the bitmap may be determined based on the maximum number of reference signal subcarriers that can be mapped in Y RBs/REs (Y is an integer greater than or equal to 1). For example, the length of the bitmap may be determined based on the maximum number of reference signal subcarriers that can be mapped in Y RBs/REs (Y is an integer greater than or equal to 1). Also, for example, the length of the bitmap may be the maximum number of reference signal subcarriers that can be mapped in Y RBs/REs. Y may be specified in advance in a specification, may be determined based on a specific rule, may be set by RRC signaling, or may be determined based on reported UE capability information.

When each bit (value) of the bitmap corresponds to multiple (X) subcarriers, the length of the bitmap may be determined based on the number of allocated subcarriers and at least one of the following: the maximum number of reference signal subcarriers that can be mapped in Y (Y is an integer greater than or equal to 1) RB/REs; a number that is predefined in the specifications; a number that is determined based on a specific rule; a number that is configured in RRC signaling; and a number that is based on a UE capability information report; multiplied by 1/X and rounded up. For example, when each bit (value) of the bitmap corresponds to multiple (X) symbols, the length of the bitmap may be determined based on the number of allocated subcarriers and at least one of the following: the maximum number of reference signal subcarriers that can be mapped in Y (Y is an integer greater than or equal to 1) RB/REs; a number that is predefined in the specifications; a number that is determined based on a specific rule; a number that is configured in RRC signaling; and a number that is based on a UE capability information report; multiplied by 1/X and rounded up.

The UE may receive an index associated with the bitmap based on RRC signaling/specific rules using DCI/MAC CE.

Figure 8 is a diagram showing an example of reference signal mapping for option 2-2-2 of the second embodiment. Figure 8 shows the case where the length of the bitmap is the number of subcarriers (here, 6) of the reference signal mapped to 1 RB (12 subcarriers).

The example shown in Figure 8 shows a case where the UE is notified of the bitmap value "101010" or "010001." The UE determines that the reference signal is mapped to the subcarrier corresponding to "1" and that the reference signal is not mapped to the subcarrier corresponding to "0."

Note that the example shown in Figure 8 describes a case where the most significant bit (MSB) of the bitmap corresponds to the lowest subcarrier, but the least significant bit (LSB) of the bitmap may also correspond to the lowest subcarrier.

Option 2-2-3
The above options 2-2-1 and 2-2-2 may be applied in combination.

The above options 2-2-1 to 2-2-3 make it possible to appropriately determine the frequency resources on which the reference signal is transmitted.

The UE may determine a frequency domain sequence (e.g., an OCC sequence) for mapping the reference signal.

The UE may determine the frequency direction sequence for mapping the reference signal based on at least one of the following options 2-3-1 and 2-3-2.

The UE may decide whether to apply option 2-3-1/2-3-2, or whether to apply either option 2-3-1 or 2-3-2, according to specific rules, may be configured by RRC signaling, or may decide based on information regarding the reference signal included in the DCI/MAC CE.

When a UE applies option 2-3-1/2-3-2, it may assume that inter-UE multiplexing of reference signals will not be performed with at least one of other UEs that do not apply option 2-3-1/2-3-2 (the same option) and other UEs that apply an option different from the option applied by the UE.

Option 2-3-1
The UE may assume/determine the value of a sequence in the frequency direction (eg, an OCC sequence) (eg, the value of w _f (k′) in the above Equations 1 and 2) to be a fixed value.

For example, the fixed value may be 1 (or -1).

In Option 2-3-1, for the first configuration type (e.g., Configuration type 1), the number of applicable DMRS ports may be limited to a specific value (e.g., only 1000 or 1001 (offset (Δ) is 0 or 1, respectively)). Also, different reference signal (e.g., DMRS) ports may be configured based on the value of k'.

In option 2-3-1, for a second configuration type (e.g., configuration type 2), the number of applicable DMRS ports may be limited to specific values (e.g., only 1000, 1001, or 1002 (offset (Δ) is 0, 2, or 4, respectively)). The CDM groups at ports 1000, 1001, and 1002 may be 0, 1, and 2, respectively. Also, different reference signal (e.g., DMRS) ports may be configured based on the value of k'.

Option 2-3-2
The UE may calculate a frequency-direction sequence (e.g., an OCC sequence) based on a specific number (e.g., N (N is an integer greater than or equal to 1)) of specific sequences, and apply the sequence to each of the specific number of subcarriers to which the reference signal is mapped.

The particular sequence may be, for example, a cyclic shift sequence.

The UE may determine the frequency direction sequence for each reference signal (DMRS) port based on N cyclic shift sequences of length N, with the rotation phase shifted by 2π/N.

N may be specified in advance in a specification, may be determined based on a specific rule, may be set by RRC signaling, or may be determined based on information regarding the reference signal included in the DCI/MAC CE.

Option 2-3-2 is suitable for use when the reference signal is mapped to N subcarriers, and multiplexing (inter-UE multiplexing) for N UEs is possible using only the frequency domain sequence (OCC).

Figures 9A and 9B are diagrams showing an example of determining a sequence for option 2-3-2 in the second embodiment. The example shown in Figures 9A and 9B shows the case where N is 3.

For example, the UE may determine the frequency-domain OCC sequence for each reference signal (DMRS) port based on three cyclic shift sequences with a sequence length of 3, each with a phase rotation amount of 2π/3 (see Figure 9A). This method is suitable for use when a reference signal is assigned to each subcarrier whose number is calculated by dividing the total number of assigned subcarriers by three.

As shown in Figure 9B, the UE may apply the OCC sequence to every fourth subcarrier within the entire RB. Alternatively, the UE may apply the OCC sequence to every third subcarrier among the subcarriers to which the DMRS is mapped.

According to the second embodiment described above, it becomes possible to appropriately specify/determine information regarding reference signals for determining the mapping of reference signals.

Third Embodiment
In the third embodiment, a method for notifying/receiving/transmitting information related to a reference signal will be described.

The UE may receive information regarding reference signals using higher layer signaling (RRC signaling/MAC CE)/physical layer signaling (DCI).

The UE may receive one or more reference signal configurations using RRC signaling.

One or more (or multiple) reference signal configurations (e.g., reference signal configurations X and Y in the first embodiment above) may be configured for the UE. One or more (or multiple) reference signal resource mappings may be configured for the UE.

The conditions for which reference signal to apply from multiple reference signal configurations may be set for the UE using RRC signaling.

The mapping of the reference signal may be associated with the time domain resource assignment (TDRA) of the UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH).

For example, each row index of the TDRA may be associated with a mapping configuration for each reference signal. When scheduling an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH), the UE may determine to apply the reference signal configuration corresponding to the row index indicated by the DCI.

The UE may receive at least one of the pieces of information regarding the reference signal in the second embodiment above using RRC signaling.

The UE may receive instructions regarding one or more reference signal configurations using the MAC CE.

For example, the UE may be instructed using MAC CE which reference signal configuration to apply from multiple reference signal configurations configured using RRC signaling.

The UE may receive at least one of the pieces of information regarding the reference signal in the second embodiment above using MAC CE.

The UE may receive information regarding the reference signal using DCI.

The DCI may be DCI transmitted individually to a UE. In other words, the DCI may be DCI transmitted in a UE-specific control resource set (CORESET)/PDCCH/search space set. The RNTI that scrambles the CRC of the DCI may be a specific RNTI (e.g., C-RNTI/CS-RNTI/MCS-C-RNTI).

By making the DCI a UE-specific DCI, each UE can report to the base station (network) whether it was able to decode the DCI.

The DCI may be a DCI that schedules/activates an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH).

The DCI may also be a DCI transmitted in common to multiple UEs (groupcast/multicast DCI). In other words, the DCI may be a DCI transmitted in a control resource set (CORESET)/PDCCH/search space set common to multiple UEs. By making the DCI a DCI common to multiple UEs, for example, when the degree of learning differs for each band (per BWP, per subband, per cell), it becomes possible to change/instruct multiple UEs using the same band at once.

The RNTI used to scramble the CRC of the DCI (DCI common to multiple UEs) may be an existing RNTI (e.g., C-RNTI/CS-RNTI/MCS-C-RNTI) or another (newly defined) RNTI.

The UE may determine the discrimination information regarding the RNTI to be used based on specific rules, based on settings via RRC signaling, or based on information regarding the reference signal received using DCI/MAC CE.

The UE may be configured with a PDCCH/CORESET/search space in which to receive the DCI.

The UE may report/send HARQ-ACK information for the DCI.

The UE may report HARQ-ACK information regarding the decoding of the received DCI a specific number (e.g., N (N is an integer greater than or equal to 1)) of symbols/slots/ms after the last symbol of the PDCCH corresponding to the DCI. N may be determined based on a specific rule, a setting via RRC signaling, a report of UE capability information, or a numerology setting (e.g., subcarrier spacing setting) based on the received DCI.

When a UE receives information regarding a reference signal using DCI common to multiple UEs, it may transmit HARQ-ACK (NACK) information only when transmitting an ACK (or NACK).

When a UE receives information regarding a reference signal using DCI common to multiple UEs, it may transmit/report information identifying the UE (e.g., C-RNTI) in addition to the HARQ-ACK information.

The UE may be instructed using DCI to select one reference signal configuration from multiple reference signal configurations configured using RRC signaling/MAC CE.

The UE may receive at least one of the pieces of information regarding the reference signal in the second embodiment above using DCI.

According to the third embodiment described above, it becomes possible to appropriately notify/transmit/receive information regarding reference signals.

<Fourth embodiment>
The fourth embodiment describes a period in which information about a reference signal is applied.

The UE may determine the period for which information regarding the reference signal is to be applied according to at least one of options 4-1 to 4-3 below.

Option 4-1
When DCI that schedules/activates an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH) includes information about a reference signal, the information about the reference signal (or a change in settings based on the information about the reference signal) may be applied to the UL channel/DL channel scheduled/activated by the DCI.

The UL channel/DL channel may include at least one of an SPS PDSCH, a configured grant (CG) PUSCH (e.g., a CG type 2 PUSCH), or repeated transmission of a PUSCH/PDSCH.

When the UL channel/DL channel is scheduled/activated by the DCI, the UE may apply information regarding the reference signal contained in the DCI to all of the UL channel/DL channel.

When the UL channel/DL channel is scheduled/activated by the DCI, the UE may apply information about the reference signal included in the DCI to the UL channel/DL channel for a specific number of transmission/reception opportunities (e.g., N) from the first transmission/reception opportunity. N may be determined based on a specific rule, a setting configured by RRC signaling, or a report of UE capability information.

When the UL channel/DL channel is scheduled/activated by DCI, the UE may apply information regarding the reference signal contained in the DCI to the UL channel/DL channel at the first transmission/reception opportunity.

Figures 10A and 10B are diagrams showing an example of application of information related to reference signals according to option 4-1 of the fourth embodiment. In Figures 10A and 10B, a UE receives a DCI that activates a CG PUSCH. The DCI includes information instructing the addition of one additional DMRS as information related to reference signals.

In the example shown in Figure 10A, the UE applies information regarding the reference signal contained in the DCI to (all) CG PUSCHs activated by the DCI.

In the example shown in Figure 10B, the UE applies information about the reference signal included in the DCI to the CG PUSCH at the first transmission opportunity among the CG PUSCHs activated by the DCI. On the other hand, the UE does not apply information about the reference signal included in the DCI to CG PUSCHs other than the CG PUSCH at the first transmission opportunity.

Option 4-2
Option 4-2 mainly describes the timing for applying information about the reference signal (starting to apply information about the reference signal).

The UE may determine/decide when to start applying information regarding the reference signal according to at least one of options 4-2-1 to 4-2-3 below.

[Option 4-2-1]
The UE may start applying the information about the reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., N) of time resources (symbols/slots/subslots/ms) after receiving the information about the reference signal (DCI/MAC CE including the information).

[Option 4-2-2]
The UE may start applying the information on the reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., N) of time resources (symbols/slots/subslots/ms) after the transmission of an UL channel (e.g., PUCCH/PUSCH) including HARQ-ACK information corresponding to the information on the reference signal (DCI/MAC CE including the information).

[Option 4-2-3]
If the DCI that schedules/activates an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH) includes information about a reference signal, the UE may start applying the information about the reference signal in a specific (e.g., first) time resource (symbol/slot/subslot) of the UL channel/DL channel scheduled/activated by the DCI.

N in the above options 4-2-1 to 4-2-3 may be a value greater than or equal to 0. N in the above options 4-2-1 to 4-2-3 may be specified in advance in a specification, may be determined according to a specific rule, may be set using RRC signaling, may be determined based on UE capability information, may be determined based on information regarding reference signals included in DCI/MAC CE, or may be determined for each numerology (e.g., subcarrier spacing setting) based on the received DCI/MAC CE.

Whether any of the above options 4-2-1 to 4-2-3 is applied may be specified in advance in the specifications, may be determined by specific rules, may be set using RRC signaling, may be determined based on UE capability information, or may be determined based on information regarding the reference signal included in the DCI/MAC CE.

Regarding Option 4-2, whether or not to apply to a specific UL channel/DL channel may be determined by a specific rule, may be configured using RRC signaling, may be determined based on UE capability information, or may be determined based on information regarding reference signals included in DCI/MAC CE. The specific UL channel/DL channel may be, for example, at least one of the PUSCH transmitting message A, the CG (Type 1/2) PUSCH, the SPS PDSCH, and the PUSCH/PDSCH scheduled/activated by DCI.

Figures 11A and 11B are diagrams showing an example of application of information related to reference signals according to option 4-2 of the fourth embodiment. In Figure 11A, application of the information related to the reference signal begins N slots after the final symbol of reception of DCI/MAC CE containing the information related to the reference signal (option 4-2-1 above). Also, in Figure 11B, application of the information related to the reference signal begins N slots after transmission of HARQ-ACK information corresponding to the information related to the reference signal (option 4-2-2 above).

Option 4-3
Option 4-3 mainly describes the timing to end application of information related to the reference signal.

The UE may determine/decide when to end application of information related to the reference signal according to at least one of options 4-3-1 to 4-3-9 below.

[Option 4-3-1]
The UE may terminate application of information related to the reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., M) of time resources (symbols/slots/subslots/ms) after the transmission of HARQ-ACK information corresponding to the RRC reconfiguration message (including the PDSCH).

[Option 4-3-2]
The UE may stop applying information about the reference signal in time resources (symbols/slots/subslots) after entering RRC inactive mode/RRC idle mode.

[Option 4-3-3]
The UE may terminate application of the information on the previous reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., M) of time resources (symbols/slots/subslots/ms) after receiving the information on the new reference signal (DCI/MAC CE including the information).

[Option 4-3-4]
The UE may terminate application of the previous information on the reference signal at the timing when application (starts) of information (DCI/MAC CE including) information on the new reference signal.

The timing for applying (starting) information regarding the new reference signal may be at least one of the timings described in option 4-2 above.

[Option 4-3-5]
The UE may terminate application of the information on the reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., M) of time resources (symbols/slots/subslots/ms) after receiving the information on the reference signal (DCI/MAC CE including the information).

[Option 4-3-6]
The UE may terminate application of the information on the reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., M) of time resources (symbols/slots/subslots/ms) after transmission of an UL channel (e.g., PUCCH/PUSCH) including HARQ-ACK information corresponding to the information on the reference signal (DCI/MAC CE including the information).

[Option 4-3-7]
If the DCI that schedules/activates an UL channel (e.g., PUSCH)/DL channel (e.g., PDSCH) includes information about a reference signal, the UE may stop applying the information about the reference signal in a time resource (symbol/slot/subslot) a specific number (e.g., M) of time resources (symbols/slots/subslots/ms) after the time resource (symbol/slot/subslot) of a specific (e.g., last) UL channel/DL channel among the UL channels/DL channels scheduled/activated by the DCI.

[Option 4-3-8]
If the DCI for scheduling/activating a DL channel (e.g., PDSCH) includes information about a reference signal, the UE may terminate application of the information about the reference signal in a time resource (symbol/slot/subslot) a certain number (e.g., M) of time resources (symbols/slots/subslots/ms) after the transmission of the UL channel (PUCCH/PUSCH) including HARQ-ACK information corresponding to the (last) DL channel to be scheduled/activated.

[Option 4-3-9]
The UE may stop applying the information related to the reference signal in at least one of a specific number (e.g., M) of time resources (symbols/slots/subslots) after starting to apply the information related to the reference signal and L UL channel transmissions/DL channel receptions.

N and L in the above options 4-3-1 to 4-3-9 may be values greater than or equal to 0. N and L in the above options 4-3-1 to 4-3-9 may be specified in advance in a specification, may be determined according to a specific rule, may be set using RRC signaling, may be determined based on UE capability information, may be determined based on information regarding reference signals included in DCI/MAC CE, or may be determined for each numerology (e.g., subcarrier spacing setting) based on the received DCI/MAC CE.

Whether any of the above options 4-3-1 to 4-3-9 is applied may be specified in advance in the specifications, may be determined by specific rules, may be set using RRC signaling, may be determined based on UE capability information, or may be determined based on information regarding the reference signal included in the DCI/MAC CE.

Regarding Option 4-3, whether or not to apply to a specific UL channel/DL channel may be determined by a specific rule, may be configured using RRC signaling, may be determined based on UE capability information, or may be determined based on information regarding the reference signal included in the DCI/MAC CE. The specific UL channel/DL channel may be, for example, at least one of the PUSCH transmitting message A, the CG (Type 1/2) PUSCH, the SPS PDSCH, and the PUSCH/PDSCH scheduled/activated by the DCI.

According to the fourth embodiment described above, it becomes possible to appropriately determine the application period of information regarding the reference signal.

Fifth Embodiment
In the fifth embodiment, a case will be described in which a reference signal (first reference signal) overlaps with another reference signal (second reference signal) different from the first reference signal.

In this embodiment, the first reference signal may refer to the reference signal in the first to fourth and sixth to ninth embodiments. In this embodiment, the second reference signal may be, for example, a CSI-RS.

The UE may assume that the information (including DCI/MAC CE) regarding the first reference signal does not include an indication that the resources of the first reference signal indicated by the information overlap with the resources of the second reference signal.

The resource of the first reference signal may be, for example, at least one of a DMRS resource, a DMRS resource of a CDM group associated with a potential DMRS port of a PDSCH, and a PTRS resource.

Note that the CDM group associated with the above-mentioned potential DMRS port may also refer to a CDM group for DMRS that is mapped to continuous/discontinuous resources in the frequency direction to which the DMRS may be mapped.

If the information (including DCI/MAC CE) regarding the first reference signal includes an indication that the resources of the first reference signal indicated by the information overlap with the resources of the second reference signal, the UE may operate based on specific rules.

The particular rule may be at least one of options 5-1 to 5-3 below.

Option 5-1
The UE may apply information about the first reference signal.

The UE may not receive/decode the second reference signal (resources) that overlap with the first reference signal (resources).

Option 5-2
The UE may not apply information about the first reference signal.

The UE may not apply all of the information regarding the first reference signal.

The UE may apply part of the information regarding the first reference signal and not apply the remaining part regarding the first reference signal.

Option 5-3
In applying the information regarding the first reference signal, the UE may apply the information by changing the resource to which the first reference signal is mapped so that the first reference signal does not overlap with the second reference signal.

For example, when applying information regarding a first reference signal, the UE may shift the resource onto which the first reference signal is mapped by a specific number of symbols so that the portion of the first reference signal that overlaps with the second reference signal does not overlap with the second reference signal.

Whether any of the above options 5-1 to 5-3 is applied may be specified in advance in the specifications, may be determined by specific rules, may be set using RRC signaling, or may be determined based on UE capability information.

This embodiment may be limited in application, for example, only to option 1-2 (or 1-3) of the first embodiment described above.

Figure 12 is a diagram showing an example of overlapping of reference signals according to the fifth embodiment. In Figure 12, the UE is receiving the SPS PDSCH.

During the first and second reception opportunities of the SPS PDSCH, the first reference signal (DMRS of the PDSCH) and the second reference signal (CSI-RS) do not overlap.

In the example shown in Figure 12, the UE receives information regarding the first reference signal and transmits an additional DMRS at the third reception opportunity.

In cases where the first reference signal and the second reference signal overlap due to instructions based on information regarding the first reference signal, as in the example shown in Figure 12, at least one of the above-mentioned options 5-2 and 5-3 may be applied.

According to the fifth embodiment described above, appropriate operation can be specified for cases where the first reference signal and the second reference signal overlap.

Sixth Embodiment
In the sixth embodiment, a PDSCH processing procedure time/PDSCH decoding time will be described.

In the present disclosure, PDSCH processing procedure time may mean the elapsed time (symbols) from the last symbol of the PDSCH to the transmission of the HARQ-ACK corresponding to that PDSCH.

The PDSCH processing procedure time may be determined based on the PDSCH decoding time. The PDSCH decoding time may be included in the PDSCH processing procedure time.

When the UE receives information regarding a reference signal, it may determine/judge the PDSCH processing procedure time/PDSCH decoding time based on at least one of options 6-1 and 6-2 below.

Option 6-1
Even if the UE receives information about reference signals, the UE may determine/decide the PDSCH processing procedure time/PDSCH decoding time based on certain higher layer (RRC) parameters.

The specific higher layer (RRC) parameter may be information regarding the additional position of the DMRS (e.g., dmrs-AdditionnalPosition) included in the DL DMRS configuration (e.g., DMRS-downlinkConfig). The specific higher layer (RRC) parameter may be a parameter that is set before receiving information regarding the reference signal.

Option 6-2
The UE may determine/judge the PDSCH processing procedure time/PDSCH decoding time based on information about the reference signal.

The information regarding the reference signal may also be information regarding the number of symbols of the additional reference signal (e.g., the number of OFDM symbols of the additional DMRS).

The settings for PDSCH processing procedure time/PDSCH decoding time corresponding to the number of symbols of the additional reference signal may be specified.

Figure 13 is a diagram showing an example of determining the PDSCH decoding time according to option 6-2 of the sixth embodiment. The UE determines/judges the PDSCH processing procedure time/PDSCH decoding time based on the correspondence relationship (e.g., a table) shown in Figure 13.

In the example shown in Figure 13, a correspondence is shown based on whether the number of OFDM symbols in the additional DMRS is 0, whether the number of OFDM symbols in the additional DMRS is 1 or more, and the PDSCH subcarrier spacing setting (μ), but the conditions and time values in the correspondence are merely examples. For example, the number of OFDM symbols in the additional DMRS that is the condition may be any value, and the number of rows indicating the number of OFDM symbols in the additional DMRS that is the condition may be 3 or more.

Whether option 6-1 or 6-2 is applied may be specified in advance in the specifications, may be determined by specific rules, may be set using RRC signaling, or may be determined based on UE capability information.

According to the sixth embodiment described above, even when the reference signal settings are dynamically changed based on information regarding the reference signal, the PDSCH processing procedure time/PDSCH decoding time can be appropriately determined/judged.

Seventh Embodiment
In the seventh embodiment, the bit width of information relating to the reference signal will be described.

At least one of options 7-1 and 7-2 below may be applied to the bit field of information regarding reference signals included in the MAC CE/DCI (format).

Option 7-1
The UE may not expect to receive a DCI/MAC CE that includes information about a reference signal whose bit width of the bit field is changed.

If multiple reference signal configurations are configured for a UE, the UE may determine/decide the bit width of the information relating to the reference signal based on a specific bit width setting.

The particular bit width setting may, for example, be a reference signal setting requiring the longest (or maximum) bit width.

For example, when a UE receives a DCI/MAC CE associated with a reference signal configuration that corresponds to a bit width that is shorter than the longest bit width, the UE may assume that the MSB (or LSB) of the bit field is padded with a fixed value (e.g., 0 (or 1)) to make it equal to the longest bit width.

Figure 14 is a diagram showing an example of the bit width of the MAC CE/DCI field for option 7-1 of the seventh embodiment. In the example shown in Figure 14, multiple reference signal configurations (DMRS configurations X and Y) are configured for the UE.

In the example shown in Figure 14, the bit field of information regarding reference signals related to DMRS setting X (in the example of Figure 14, the antenna port field for DMRS setting X) is shorter than the bit field of information regarding reference signals related to DMRS setting Y. In this case, the bit width of the information included in the MAC CE/DCI is calculated based on the bit width of the bit field of information regarding reference signals related to DMRS setting Y, which requires a longer (longest) bit field.

In this case, the bit width of the information regarding the reference signal related to DMRS setting X is padded with a fixed value (0) so that it is equal to the bit width of the information regarding the reference signal related to DMRS setting Y.

Option 7-2
For the UE, it may be configured whether or not the bit width of the bit field of the information related to the reference signal included in the MAC CE/DCI (format) can be changed.

This configuration may be performed using higher layer signaling (RRC signaling/MAC CE)/physical layer signaling (DCI).

If the UE is configured not to change the bit width of the bit field for information regarding reference signals contained in the MAC CE/DCI (format), the UE may operate according to at least one of options 7-2-1 to 7-2-3 below.

[Option 7-2-1]
The UE may not expect to receive a MAC CE/DCI containing information about reference signals whose bit widths are changed.

[Option 7-2-2]
The UE may receive a MAC CE/DCI that includes information about the reference signal whose bit width is to be changed.

The UE may not apply information regarding the reference signal contained in the MAC CE/DCI.

[Option 7-2-3]
The UE may receive a MAC CE/DCI that includes information about the reference signal whose bit width is to be changed.

The UE may, in certain cases, apply information regarding the reference signal contained in the MAC CE/DCI.

The specific case may be, for example, when the information about the reference signal is shorter than the bit width required for the already-set reference signal configuration. Alternatively, the specific case may be, for example, when the information about the reference signal is equal to the bit width required for the already-set reference signal configuration.

The UE may not expect to receive a MAC CE/DCI containing information regarding a reference signal that is changed to a bit width longer than the bit width required for the already configured reference signal configuration.

When a UE receives a DCI/MAC CE associated with a reference signal configuration that corresponds to a bit width that is shorter than the longest bit width, the UE may assume that the MSB (or LSB) of the bit field is padded with a fixed value (e.g., 0 (or 1)) to make it equal to the longest bit width.

When a MAC CE/DCI is received that includes information about a reference signal that is changed to a bit width longer than the bit width required for the already configured reference signal configuration, the UE does not have to apply all of the information about the reference signal.

When receiving a MAC CE/DCI containing information about a reference signal that is changed to a bit width longer than the bit width required for the already configured reference signal configuration, the UE may apply only part of the information about the reference signal.

Whether any of the above options 7-2-1 to 7-2-3 is applied may be specified in advance in the specifications, may be determined by specific rules, may be set using RRC signaling, or may be determined based on UE capability information.

According to the seventh embodiment described above, the bit field of information regarding the reference signal can be appropriately determined even when the mapping of the reference signal is dynamically set/instructed.

Eighth Embodiment
In the eighth embodiment, restrictions on additional reference signals will be described.

Regarding the number of symbols of the additional reference signal, at least one of options 8-1 and 8-2 below may be applied.

In this embodiment, the terms "additional reference signal" and "additional DMRS" may be interchangeable. Also, in the present disclosure, the terms "number of symbols of an additional reference signal" and "number of OFDM symbols of an additional DMRS" may be interchangeable.

In this embodiment, the number of symbols of the additional reference signal may be limited/determined based on the symbol position of the first (initial) reference signal. In this case, the first (initial) reference signal may be a reference signal of a specific mapping type (e.g., mapping type A).

In this embodiment, the number of symbols of the additional reference signal may be limited/determined based on the symbol position of the front-loaded reference signal.

In the present disclosure, the above restriction may mean that the number of symbols of additional reference signals is limited based on at least one of an upper layer parameter (e.g., dmrs-TypeA-Position) indicating the position of the initial (first) reference signal, the mapping type of the UL/DL channel, and the duration of the UL/DL channel.

In the present disclosure, the above restriction may mean that the number of symbols of additional reference signals is limited based on an upper layer parameter (e.g., maxLength) indicating the maximum number of front-loaded reference signals.

Option 8-1
The UE may assume that the information regarding the reference signals does not include any configuration/instruction to exceed the limit on the number of symbols of the additional reference signals.

Option 8-2
If the information about the reference signal includes a setting/instruction to exceed the limit on the number of symbols of the additional reference signal, the UE may operate based on at least one of options 8-2-1 and 8-2-2 below.

[Option 8-2-1]
The UE may apply information about the reference signal regardless of the restriction on the number of symbols of the additional reference signal.

[Option 8-2-2]
The UE may not apply information about the reference signal that indicates mapping of the reference signal beyond the limit of the number of symbols of the additional reference signal.

The UE may not apply all information about the received reference signals.

The UE may not apply all of the information about the received reference signal.

Whether the above options 8-2-1 and 8-2-2 are applied may be specified in advance in the specifications, may be determined by specific rules, may be set using RRC signaling, or may be determined based on UE capability information.

According to the eighth embodiment described above, even when the mapping of reference signals is dynamically set/instructed, operations related to limiting the number of symbols of additional reference signals can be performed appropriately.

Ninth Embodiment
At least one of the above-described embodiments may be applied only to UEs that have reported or support a particular UE capability.

The specific UE capabilities may indicate at least one of the following:
Whether or not each embodiment supports specific operations/information.
Whether or not application of each option/combination of options in each embodiment is supported.

The above UE capabilities may be reported as whether the UE is capable of supporting them or not.

The UE capabilities may be reported for all frequencies, by frequency, by frequency range (e.g., Frequency Range 1 (FR1), Frequency Range 2 (FR2), FR2-1, FR2-2), by cell, or by subcarrier spacing (SubCarrier Spacing (SCS)).

The above UE capabilities may be reported jointly for Time Division Duplex (TDD) and Frequency Division Duplex (FDD), or may be reported independently.

Furthermore, at least one of the above-described embodiments may be applied when the UE is configured with specific information related to the above-described embodiments by higher layer signaling. For example, the specific information may be information indicating reduced CSI feedback/enabling reduced CSI feedback, any RRC parameter for a specific release (e.g., Rel. 18), etc.

According to the above ninth embodiment, the UE can realize the above functions while maintaining compatibility with existing specifications.

(wireless communication system)
The configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination thereof.

Figure 15 is a diagram showing an example of the schematic configuration of a wireless communication system according to one embodiment. The wireless communication system 1 may be a system that realizes communication using Long Term Evolution (LTE) specified by the Third Generation Partnership Project (3GPP), 5th generation mobile communication system New Radio (5G NR), or the like.

The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (e.g., dual connectivity in which both the MN and SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with relatively wide coverage, and base stations 12 (12a-12c) that are located within the macrocell C1 and form a small cell C2 that is smaller than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The location and number of each cell and user terminal 20 are not limited to the configuration shown in the figure. Hereinafter, when there is no need to distinguish between base stations 11 and 12, they will be collectively referred to as base station 10.

The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). Macro cell C1 may be included in FR1, and small cell C2 may be included in FR2. For example, FR1 may be a frequency band below 6 GHz (sub-6 GHz), and FR2 may be a frequency band above 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a higher frequency band than FR2.

In addition, the user terminal 20 may communicate using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD) in each CC.

Multiple base stations 10 may be connected by wire (e.g., optical fiber compliant with the Common Public Radio Interface (CPRI), X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between base stations 11 and 12, base station 11, which corresponds to the upper station, may be called an Integrated Access Backhaul (IAB) donor, and base station 12, which corresponds to the relay station, may be called an IAB node.

A base station 10 may be connected to a core network 30 via another base station 10 or directly. The core network 30 may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), etc.

The user terminal 20 may be a terminal compatible with at least one of the communication methods such as LTE, LTE-A, and 5G.

In the wireless communication system 1, a wireless access method based on Orthogonal Frequency Division Multiplexing (OFDM) may be used. For example, in at least one of the downlink (DL) and uplink (UL), Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), etc. may be used.

A radio access method may also be called a waveform. In wireless communication system 1, other radio access methods (e.g., other single-carrier transmission methods, other multi-carrier transmission methods) may be used for the UL and DL radio access methods.

In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as a downlink channel.

In addition, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. may be used as an uplink channel.

User data, upper layer control information, System Information Block (SIB), etc. are transmitted via PDSCH. User data, upper layer control information, etc. may also be transmitted via PUSCH. Furthermore, Master Information Block (MIB) may also be transmitted via PBCH.

Lower layer control information may be transmitted via the PDCCH. The lower layer control information may include, for example, Downlink Control Information (DCI) including scheduling information for at least one of the PDSCH and the PUSCH.

Note that the DCI that schedules the PDSCH may be called a DL assignment, DL DCI, etc., and the DCI that schedules the PUSCH may be called an UL grant, UL DCI, etc. Note that the PDSCH may be interpreted as DL data, and the PUSCH may be interpreted as UL data.

Detection of the PDCCH may utilize a control resource set (CORESET) and a search space. The CORESET corresponds to the resources to search for DCI. The search space corresponds to the search region and search method for PDCCH candidates. One CORESET may be associated with one or more search spaces. The UE may monitor the CORESET associated with a certain search space based on the search space configuration.

One search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," "CORESET setting," etc. in the present disclosure may be read interchangeably.

The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (which may be referred to as, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK/NACK, etc.), and scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

Note that in this disclosure, downlink, uplink, etc. may be expressed without the word "link." Also, various channels may be expressed without the word "Physical" at the beginning.

In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted as the DL-RS.

The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRS for the PBCH) may be referred to as an SS/PBCH block, an SS Block (SSB), etc. Note that SS, SSB, etc. may also be referred to as a reference signal.

In addition, in the wireless communication system 1, a sounding reference signal (SRS), a demodulation reference signal (DMRS), etc. may be transmitted as an uplink reference signal (UL-RS). DMRS may also be called a user equipment-specific reference signal (UE-specific Reference Signal).

(base station)
16 is a diagram illustrating an example of the configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that the base station may include one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140.

Note that this example mainly shows the functional blocks that characterize this embodiment, and the base station 10 may also have other functional blocks necessary for wireless communication. Some of the processing of each unit described below may be omitted.

The control unit 110 controls the entire base station 10. The control unit 110 can be composed of a controller, a control circuit, etc., which are described based on common understanding in the technical field related to this disclosure.

The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may also control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurements, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transceiver unit 120. The control unit 110 may also perform call processing of communication channels (setting up, releasing, etc.), status management of the base station 10, management of radio resources, etc.

The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be composed of a transmitter/receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

The transmitter/receiver unit 120 may be configured as an integrated transmitter/receiver unit, or may be composed of a transmitter unit and a receiver unit. The transmitter unit may be composed of a transmission processing unit 1211 and an RF unit 122. The receiver unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

The transmitting and receiving antenna 130 may be composed of an antenna described based on common understanding in the technical field to which this disclosure relates, such as an array antenna.

The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

The transceiver unit 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

The transceiver unit 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 110, and generate a bit string to be transmitted.

The transmitter/receiver unit 120 (transmission processing unit 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit sequence to be transmitted, and output a baseband signal.

The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

The transceiver unit 120 (receiving processing unit 1212) may apply receiving processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, thereby acquiring user data, etc.

The transceiver unit 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

The transmission path interface 140 may send and receive signals (backhaul signaling) between devices included in the core network 30, other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

In addition, the transmitting unit and receiving unit of the base station 10 in the present disclosure may be composed of at least one of the transmitting/receiving unit 120, the transmitting/receiving antenna 130, and the transmission path interface 140.

The transceiver 120 may transmit one or more reference signal configurations. The controller 110 may control at least one of the transmission and reception of the reference signal to which at least a portion of at least one of the reference signal configurations has been applied, based on at least one of information related to the reference signal and specific conditions (first embodiment).

The transceiver unit 120 may transmit one or more reference signal configurations using Radio Resource Control (RRC) signaling, and may transmit information regarding the reference signals using at least one of Downlink Control Information (DCI) and Medium Access Control (MAC) control elements (CE). The control unit 110 may determine the mapping of the reference signals using the reference signal configurations and information regarding the reference signals (second and third embodiments).

The transceiver unit 120 may transmit one or more reference signal settings and information related to the reference signals. The control unit 110 may determine the application period of the information related to the reference signals and determine the mapping of the reference signals using the reference signal settings and the information related to the reference signals (fourth embodiment).

The transceiver 120 may transmit information regarding a reference signal using at least one of downlink control information (DCI) and a medium access control (MAC) control element (CE). The control unit 110 may control the transmission of the reference signal and the other reference signal when the resource of the reference signal based on the information regarding the reference signal overlaps with the resource of another reference signal different from the reference signal (fifth embodiment).

(user terminal)
17 is a diagram showing an example of the configuration of a user terminal according to one embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the user terminal 20 may include one or more of each of the control unit 210, the transceiver unit 220, and the transceiver antenna 230.

Note that this example mainly shows the functional blocks of the characteristic parts of this embodiment, and it may be assumed that the user terminal 20 also has other functional blocks necessary for wireless communication. Some of the processing of each part described below may be omitted.

The control unit 210 controls the entire user terminal 20. The control unit 210 can be composed of a controller, a control circuit, etc., which are described based on common understanding in the technical field to which this disclosure relates.

The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission and reception, measurement, etc. using the transceiver unit 220 and the transceiver antenna 230. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals and transfer them to the transceiver unit 220.

The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be composed of a transmitter/receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on common understanding in the technical field related to the present disclosure.

The transmitter/receiver unit 220 may be configured as an integrated transmitter/receiver unit, or may be composed of a transmitter unit and a receiver unit. The transmitter unit may be composed of a transmission processing unit 2211 and an RF unit 222. The receiver unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

The transmitting/receiving antenna 230 may be composed of an antenna described based on common understanding in the technical field to which this disclosure relates, such as an array antenna.

The transceiver unit 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver unit 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

The transceiver unit 220 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

The transceiver unit 220 (transmission processing unit 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on data, control information, etc. obtained from the control unit 210, and generate a bit string to be transmitted.

The transceiver unit 220 (transmission processing unit 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit sequence to be transmitted, and output a baseband signal.

Whether or not to apply DFT processing may be based on the settings of transform precoding. If transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the transmission processing to transmit the channel using a DFT-s-OFDM waveform; if not, it may not be necessary to perform DFT processing as the transmission processing.

The transceiver unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc. on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 230.

On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 230.

The transceiver unit 220 (receiving processing unit 2212) may apply receiving processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to acquire user data, etc.

The transceiver unit 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

In addition, the transmitting unit and receiving unit of the user terminal 20 in the present disclosure may be constituted by at least one of the transmitting/receiving unit 220 and the transmitting/receiving antenna 230.

The transceiver unit 220 may receive one or more reference signal configurations. The control unit 210 may control the application of at least one of the reference signal configurations based on at least one of information about the reference signal and specific conditions (first embodiment).

The reference signal setting may include at least one of setting a demodulation reference signal and setting a phase tracking reference signal (first embodiment).

The control unit 210 may select/determine one reference signal setting from multiple reference signal settings based on information about the reference signal and the specific conditions (first embodiment).

The specific condition may be a condition based on at least one of the following: application of bundling of reference signals; whether a channel spanning multiple slots is transmitted; overlap with other reference signals different from the reference signal; modulation order; number of layers; number of ports of the reference signal; format of downlink control information for scheduling a physical downlink shared channel or a physical uplink shared channel; whether the reference signal is used for a specific channel; a radio network temporary identifier used to scramble a cyclic redundancy check of the downlink control information; setting of a configured grant; whether the downlink control information includes information about the reference signal; the state of the terminal corresponding to a learning state; and the speed of the terminal (first embodiment).

The transceiver unit 220 may receive one or more reference signal configurations using Radio Resource Control (RRC) signaling, and may receive information regarding the reference signals using at least one of Downlink Control Information (DCI) and Medium Access Control (MAC) control elements (CE). The control unit 210 may control the mapping of the reference signals based on the reference signal configurations and information regarding the reference signals (second and third embodiments).

The control unit 210 may determine at least one of the slots and symbols to which the reference signal is not mapped based on information regarding the reference signal (second embodiment).

The control unit 210 may determine the subcarriers to which the reference signal is not mapped based on information regarding the reference signal (second embodiment).

The control unit 210 may determine the orthogonal cover code sequence to be applied to the reference signal based on information about the reference signal (second embodiment).

The transceiver unit 220 may receive one or more reference signal settings and information related to the reference signals. The control unit 210 may determine the application period of the information related to the reference signals and determine the mapping of the reference signals based on the reference signal settings and the information related to the reference signals (fourth embodiment).

If the reference signal is a reference signal for a channel that is scheduled or activated across multiple slots, the control unit 210 may apply information about the reference signal to all of the channels (fourth embodiment).

If the reference signal is a reference signal for a channel that is scheduled or activated over multiple slots, the control unit 210 may apply information about the reference signal at the first transmission opportunity for the channel (fourth embodiment).

The control unit 210 may determine at least one of the start and end of application of the information regarding the reference signal after a first period has elapsed after receiving the information regarding the reference signal, and at least one of the first period has elapsed after receiving a Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK) for downlink control information including the information regarding the reference signal (fourth embodiment).

The transceiver 220 may receive information about a reference signal using at least one of Downlink Control Information (DCI) and Medium Access Control (MAC) Control Element (CE). The control unit 210 may control reception of the reference signal and the other reference signal when the resources of the reference signal based on the information about the reference signal overlap with the resources of another reference signal different from the reference signal (fifth embodiment).

The control unit 210 may determine the decoding time of the physical downlink shared channel based on information regarding additional reference signals included in the DCI (sixth embodiment).

Even if multiple reference signal settings are set and the bit width required for the information regarding the reference signal for each of the multiple reference signal settings is different, the control unit 210 may determine that the bit width of the information regarding the reference signal is a fixed value, or may assume that the bit width is padded to the fixed value (seventh embodiment).

The control unit 210 may also determine whether the information regarding the reference signal includes an instruction to exceed the limit on the number of symbols of the additional reference signal (8th embodiment).

(Hardware configuration)
The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of hardware and/or software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (e.g., wired, wireless, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or multiple devices.

Here, functions include, but are not limited to, judgment, determination, assessment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission functions may be called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

For example, a base station, a user terminal, etc. in one embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Figure 18 is a diagram showing an example of the hardware configuration of a base station and a user terminal according to one embodiment. The above-mentioned base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, memory 1002, storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

In this disclosure, terms such as apparatus, circuit, device, section, and unit may be used interchangeably. The hardware configuration of the base station 10 and user terminal 20 may be configured to include one or more of the devices shown in the figures, or may be configured to exclude some of the devices.

For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, sequentially, or using other techniques. Furthermore, processor 1001 may be implemented by one or more chips.

Each function in the base station 10 and the user terminal 20 is realized, for example, by loading specified software (programs) onto hardware such as the processor 1001 and memory 1002, causing the processor 1001 to perform calculations, control communication via the communication device 1004, and control at least one of reading and writing data in the memory 1002 and storage 1003.

The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, registers, etc. For example, at least a portion of the above-mentioned control unit 110 (210), transceiver unit 120 (220), etc. may be realized by the processor 1001.

The processor 1001 also reads programs (program code), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 110 (210) may be realized by a control program stored in the memory 1002 and running on the processor 1001, and similar implementations may be used for other functional blocks.

Memory 1002 is a computer-readable recording medium and may be composed of, for example, at least one of Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EEPROM (EEPROM), Random Access Memory (RAM), or other suitable storage medium. Memory 1002 may also be referred to as a register, cache, main memory, etc. Memory 1002 may store executable programs (program code), software modules, etc. for implementing a wireless communication method according to one embodiment of the present disclosure.

Storage 1003 is a computer-readable recording medium and may be constituted by at least one of, for example, a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disk (e.g., a Compact Disc ROM (CD-ROM)), a digital versatile disk, a Blu-ray disc), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, stick, key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

The communication device 1004 is hardware (transmitting/receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as a network device, network controller, network card, or communication module. The communication device 1004 may be configured to include a high-frequency switch, duplexer, filter, frequency synthesizer, etc. to implement at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD). For example, the above-mentioned transmitter/receiver unit 120 (220), transmitter/receiver antenna 130 (230), etc. may be implemented by the communication device 1004. The transmitter/receiver unit 120 (220) may be implemented as a transmitter unit 120a (220a) and a receiver unit 120b (220b) that are physically or logically separated.

The input device 1005 is an input device (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, speaker, Light Emitting Diode (LED) lamp, etc.) that outputs to the outside. Note that the input device 1005 and the output device 1006 may be integrated into one structure (e.g., a touch panel).

Furthermore, each device such as the processor 1001 and memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using such hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

(Modification)
Note that terms described in the present disclosure and terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may also be called a pilot, pilot signal, etc. depending on the applicable standard. A component carrier (CC) may also be called a cell, frequency carrier, carrier frequency, etc.

A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

Here, numerology may be a communication parameter applied to at least one of the transmission and reception of a signal or channel. Numerology may indicate, for example, at least one of subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, and specific windowing operations performed by the transceiver in the time domain.

A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols or Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols). A slot may also be a time unit based on numerology.

A slot may include multiple minislots. Each minislot may consist of one or more symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

Radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals. Radio frame, subframe, slot, minislot, and symbol may be referred to by other names that correspond to them. Note that the time units such as frame, subframe, slot, minislot, and symbol used in this disclosure may be interpreted interchangeably.

For example, one subframe may be referred to as a TTI, multiple consecutive subframes may be referred to as a TTI, or one slot or one minislot may be referred to as a TTI. In other words, at least one of a subframe and a TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing a TTI may be called a slot, minislot, etc. instead of a subframe.

Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station schedules each user terminal by allocating radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) in TTI units. Note that the definition of TTI is not limited to this.

A TTI may be a transmission time unit for a channel-coded data packet (transport block), code block, code word, etc., or may be a processing unit for scheduling, link adaptation, etc. Note that when a TTI is given, the time interval (e.g., the number of symbols) to which a transport block, code block, code word, etc. is actually mapped may be shorter than the TTI.

Note that when one slot or one minislot is referred to as a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the smallest time unit for scheduling. Furthermore, the number of slots (minislots) that constitute the smallest time unit for scheduling may be controlled.

A TTI with a time length of 1 ms may be referred to as a regular TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be referred to as a shortened TTI, short TTI, partial TTI (partial or fractional TTI), shortened subframe, short subframe, minislot, subslot, slot, etc.

Note that a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than that of a long TTI and greater than or equal to 1 ms.

A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

In addition, an RB may include one or more symbols in the time domain and may be one slot, one minislot, one subframe, or one TTI in length. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

In addition, one or more RBs may also be referred to as a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, etc.

A resource block may also be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

A Bandwidth Part (BWP) (which may also be referred to as a partial bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within that BWP.

BWPs may include UL BWPs (BWPs for UL) and DL BWPs (BWPs for DL). One or more BWPs may be configured for a UE within one carrier.

At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal/channel outside the active BWP. Note that the terms "cell," "carrier," etc. in this disclosure may be read as "BWP."

Note that the structures of the radio frames, subframes, slots, minislots, and symbols described above are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, as well as the number of symbols in a TTI, symbol length, and cyclic prefix (CP) length can be varied in various ways.

Furthermore, the information, parameters, etc. described in this disclosure may be expressed using absolute values, relative values from a predetermined value, or other corresponding information. For example, radio resources may be indicated by a predetermined index.

The names used for parameters and the like in this disclosure are not intended to be limiting in any way. Furthermore, the mathematical formulas and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not intended to be limiting in any way.

The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

In addition, information, signals, etc. may be output from a higher layer to a lower layer and/or from a lower layer to a higher layer. Information, signals, etc. may be input/output via multiple network nodes.

Input and output information, signals, etc. may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information, signals, etc. may be overwritten, updated, or added to. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

The notification of information is not limited to the aspects/embodiments described in the present disclosure and may be performed using other methods. For example, the notification of information in the present disclosure may be performed using physical layer signaling (e.g., Downlink Control Information (DCI) and Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB) and System Information Block (SIB)), Medium Access Control (MAC) signaling), other signals, or a combination thereof.

Note that physical layer signaling may also be referred to as Layer 1/Layer 2 (L1/L2) control information (L1/L2 control signal), L1 control information (L1 control signal), etc. Furthermore, RRC signaling may also be referred to as RRC messages, such as RRC Connection Setup messages and RRC Connection Reconfiguration messages. Furthermore, MAC signaling may also be notified using, for example, MAC Control Elements (CEs).

Furthermore, notification of specified information (e.g., notification that "it is X") is not limited to explicit notification, but may also be made implicitly (e.g., by not notifying the specified information or by notifying other information).

The determination may be made by a value represented by a single bit (0 or 1), by a Boolean value represented by true or false, or by a numerical comparison (e.g., comparison with a predetermined value).

Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Software, instructions, information, etc. may also be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and/or wireless technologies (such as infrared, microwave), these wired and/or wireless technologies are included within the definition of transmission media.

As used in this disclosure, the terms "system" and "network" may be used interchangeably. "Network" may refer to devices included in the network (e.g., base stations).

In this disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," and "panel" may be used interchangeably.

In this disclosure, terms such as "Base Station (BS)," "Radio Base Station," "Fixed Station," "NodeB," "eNB (eNodeB)," "gNB (gNodeB)," "Access Point," "Transmission Point (TP)," "Reception Point (RP)," "Transmission/Reception Point (TRP)," "Panel," "Cell," "Sector," "Cell Group," "Carrier," and "Component Carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head (RRH))). The terms "cell" or "sector" refer to part or all of the coverage area of a base station and/or base station subsystem that provides communication services within this coverage area.

In this disclosure, terms such as "Mobile Station (MS)," "user terminal," "User Equipment (UE)," and "terminal" may be used interchangeably.

A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a wireless communication device, etc. Note that at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

The term "mobile body" refers to a movable object that can move at any speed and naturally includes cases where the mobile body is stationary. Examples of such mobile bodies include, but are not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcarts, rickshaws, ships and other watercraft, airplanes, rockets, satellites, drones, multicopters, quadcopters, balloons, and objects carried by these. Furthermore, the mobile body may be a mobile body that moves autonomously based on operational commands.

The mobile object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile object (e.g., a drone, a self-driving car, etc.), or a robot (manned or unmanned). Note that at least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

Figure 19 is a diagram showing an example of a vehicle according to one embodiment. The vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, an axle 48, an electronic control unit 49, various sensors (including a current sensor 50, an RPM sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

The drive unit 41 is composed of, for example, at least one of an engine, a motor, or a hybrid of an engine and a motor. The steering unit 42 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by the user.

The electronic control unit 49 is composed of a microprocessor 61, memory (ROM, RAM) 62, and a communication port (e.g., an input/output (IO) port) 63. Signals are input to the electronic control unit 49 from various sensors 50-58 provided in the vehicle. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

Signals from the various sensors 50-58 include a current signal from a current sensor 50 that senses the motor current, a rotation speed signal for the front wheels 46/rear wheels 47 obtained by a rotation speed sensor 51, an air pressure signal for the front wheels 46/rear wheels 47 obtained by an air pressure sensor 52, a vehicle speed signal obtained by a vehicle speed sensor 53, an acceleration signal obtained by an acceleration sensor 54, a depression amount signal for the accelerator pedal 43 obtained by an accelerator pedal sensor 55, a depression amount signal for the brake pedal 44 obtained by a brake pedal sensor 56, an operation signal for the shift lever 45 obtained by a shift lever sensor 57, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. obtained by an object detection sensor 58.

The information service unit 59 is composed of various devices, such as a car navigation system, audio system, speakers, displays, televisions, and radios, for providing (outputting) various information such as driving information, traffic information, and entertainment information, as well as one or more ECUs that control these devices. The information service unit 59 uses information obtained from external devices via the communication module 60, etc., to provide various information/services (e.g., multimedia information/multimedia services) to the occupants of the vehicle 40.

The information service unit 59 may include input devices (e.g., keyboards, mice, microphones, switches, buttons, sensors, touch panels, etc.) that accept input from the outside, and may also include output devices (e.g., displays, speakers, LED lamps, touch panels, etc.) that output to the outside.

The driving assistance system unit 64 is composed of various devices that provide functions to prevent accidents and reduce the driver's driving burden, such as millimeter-wave radar, Light Detection and Ranging (LiDAR), cameras, positioning locators (e.g., Global Navigation Satellite System (GNSS)), map information (e.g., High Definition (HD) maps, Autonomous Vehicle (AV) maps), gyro systems (e.g., Inertial Measurement Unit (IMU) and Inertial Navigation System (INS)), artificial intelligence (AI) chips, and AI processors, as well as one or more ECUs that control these devices. The driving assistance system unit 64 also transmits and receives various information via the communication module 60 to realize driving assistance or autonomous driving functions.

The communication module 60 can communicate with the microprocessor 61 and components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 between the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and various sensors 50-58, all of which are provided on the vehicle 40.

The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with external devices. For example, it transmits and receives various information to and from external devices via wireless communication. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the base station 10 or user terminal 20 described above. Furthermore, the communication module 60 may be, for example, at least one of the base station 10 and user terminal 20 described above (or may function as at least one of the base station 10 and user terminal 20).

The communication module 60 may transmit at least one of the following to an external device via wireless communication: signals from the various sensors 50-58 described above input to the electronic control unit 49; information obtained based on the signals; and information based on input from the outside (user) obtained via the information service unit 59. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above input.

The communication module 60 receives various information (traffic information, traffic signal information, vehicle distance information, etc.) transmitted from external devices and displays it on the information service unit 59 installed in the vehicle. The information service unit 59 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data/information decoded from the PDSCH) received by the communication module 60).

The communication module 60 also stores various information received from external devices in memory 62 that can be used by the microprocessor 61. Based on the information stored in memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, various sensors 50-58, and the like provided on the vehicle 40.

Furthermore, the base station in the present disclosure may be read as a user terminal. For example, each aspect/embodiment of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.). In this case, the user terminal 20 may be configured to have the functions possessed by the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "sidelink"). For example, terms such as uplink channel and downlink channel may be read as sidelink channel.

Similarly, the user terminal in this disclosure may be interpreted as a base station. In this case, the base station 10 may be configured to have the functions of the user terminal 20 described above.

In this disclosure, operations described as being performed by a base station may in some cases also be performed by its upper node. It is clear that in a network including one or more network nodes having base stations, various operations performed for communication with terminals may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME), a Serving-Gateway (S-GW), etc.), or a combination thereof.

Each aspect/embodiment described in this disclosure may be used alone, in combination, or switched between depending on the implementation. Furthermore, the processing procedures, sequences, flowcharts, etc. of each aspect/embodiment described in this disclosure may be rearranged unless inconsistent. For example, the methods described in this disclosure present elements of various steps in an exemplary order, and are not limited to the particular order presented.

The aspects/embodiments described in this disclosure may be implemented using standards such as Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or decimal number)), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.17 (WiMAX (registered trademark)), IEEE 802.18 (WiMAX (registered trademark)), IEEE 802.19 (WiMAX (registered trademark)), IEEE 802.20 (WiMAX (registered trademark)), IEEE 802.21 (Wi-Fi (registered trademark)), IEEE 802.22 (WiMAX (registered trademark)), IEEE 802.23 (WiMAX (registered trademark)), IEEE 802.24 (WiMAX (registered trademark)), IEEE 802.25 (WiMAX (registered trademark)), IEEE 802.26 (WiMAX (registered trademark)), IEEE 802.27 (WiMAX (registered trademark)), IEEE 802.28 (WiMAX (registered trademark)), IEEE 802.29 ... The present invention may be applied to systems that use IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable wireless communication methods, or to next-generation systems that are expanded, modified, created, or defined based on these. Furthermore, the present invention may be applied to a combination of multiple systems (e.g., a combination of LTE or LTE-A and 5G).

As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

As used in this disclosure, the term "determining" may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., searching in a table, database, or another data structure), ascertaining, etc.

"Determining" may also be considered to be "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), etc.

"Judgment" may also be considered to be "deciding" on resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" may also be considered to be "deciding" on some action.

In addition, "judgment (decision)" can also be interpreted as "assuming," "expecting," "considering," etc.

As used in this disclosure, the terms "connected," "coupled," or any variation thereof, mean any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access."

For the purposes of this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, etc., as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, etc., as some non-limiting and non-exhaustive examples.

In this disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "combined" may also be interpreted in the same way as "different."

When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

In this disclosure, where articles are added by translation, such as a, an, and the in English, this disclosure may include the noun following these articles being plural.

The invention according to the present disclosure has been described in detail above, but it will be clear to those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described herein. The invention according to the present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and explanatory and does not pose any limiting meaning to the invention according to the present disclosure.

Claims (4)

a receiver for receiving one or more reference signal configurations and information about the reference signals;
a control unit that determines an application period of information related to the reference signal, and determines mapping of the reference signal based on the reference signal setting and the information related to the reference signal ;
When the reference signal is a reference signal for a channel scheduled over a plurality of slots, the control unit applies information related to the reference signal to all of the channels . receiving one or more reference signal configurations and information about the reference signals;
determining an application period of the information about the reference signal, and controlling mapping of the reference signal based on the reference signal configuration and the information about the reference signal ;
A wireless communication method for a terminal , wherein, when the reference signal is a reference signal for a channel scheduled over a plurality of slots, information about the reference signal is applied to all of the channels . a transmitter configured to transmit one or more reference signal configurations and information related to the reference signals;
a control unit that determines an application period of information related to the reference signal, and determines mapping of the reference signal using the reference signal configuration and the information related to the reference signal ;
When the reference signal is a reference signal for a channel scheduled over a plurality of slots, the transmitter transmits information regarding the reference signal to be applied to all of the channels . A system including a terminal and a base station,
The terminal
a receiver for receiving one or more reference signal configurations and information about the reference signals;
a control unit that determines an application period of information related to the reference signal, and determines mapping of the reference signal based on the reference signal setting and the information related to the reference signal;
When the reference signal is a reference signal for a channel scheduled over a plurality of slots, the control unit applies information about the reference signal to all of the channels;
The base station
A system comprising the reference signal setting and a transmitter that transmits information about the reference signal.