JP7833042B2 - Terminals and communication methods - Google Patents

Description

This invention relates to a terminal and a communication method in a wireless communication system.

In NR (New Radio) (also known as "5G"), the successor system to LTE (Long Term Evolution), technologies are being considered to meet requirements such as large-capacity systems, high-speed data transmission rates, low latency, simultaneous connection of numerous terminals, low cost, and low power consumption (for example, Non-Patent Document 1).

Dynamic spectrum sharing (DSS), a technology that allows LTE and NR to coexist within the same band, is being considered (for example, Non-Patent Document 2). By allowing different RATs (Radio Access Technologies) to coexist on a single carrier, it becomes possible to flexibly respond to traffic demands during system generation transitions. Furthermore, in order to increase the capacity of the NR-PDCCH (Physical Downlink Control Channel) during DSS, NR-PDCCH reception on symbols where the LTE-CRS (Cell specific reference signal) is located is being considered (for example, Non-Patent Document 3).

3GPP TS 38.300 V17.0.0 (2022-03) 3GPP TSG RAN Meeting #86 RP-192678 (2019-12) 3GPP TSG RAN Meeting#94e RP-213575 (2021-12) 3GPP TS 38.213 V17.1.0 (2022-03)

The DSS specification transmits signals to LTE terminals and NR terminals, respectively. Because LTE has many continuously transmitted signals, it was difficult to secure sufficient resources for NR-PDCH.

The present invention has been made in view of the above points, and aims to secure control signal resources when multiple RATs (Radio Access Technologies) coexist on a single carrier in a wireless communication system.

According to the disclosed technology, an RRC (Radio Resource) includes first information that enables monitoring of a candidate downlink control channel for a second RAT, which includes a resource element where the reference signal of a first RAT (Radio Access Technology) is located. A terminal is provided, comprising: a receiving unit that receives RRC signaling from a network; a control unit that monitors the downlink control channel candidate, including the resource element on which the reference signal is located, based on the first information in the RRC signaling; and a transmitting unit that transmits terminal capability information to the network, including second information regarding whether the downlink control channel candidate of the second RAT, including the resource element on which the reference signal of the first RAT is located, can be received; the receiving unit receives the RRC signaling including the first information after transmitting the terminal capability information, the RRC signaling includes fourth information regarding the pattern of the reference signal, the control unit monitors the downlink control channel candidate, including the resource element on which the reference signal is located, based on the fourth information in the RRC signaling, the RRC signaling includes fifth information regarding the search space of the downlink control channel candidate, and the control unit monitors the downlink control channel candidate when the downlink link channel candidate based on the fifth information overlaps with the resource element based on the fourth information .

According to the disclosed technology, in a wireless communication system, it is possible to secure control signal resources when multiple RATs (Radio Access Technologies) coexist on a single carrier.

This is a diagram showing an example configuration of a wireless communication system (1). This figure shows an example configuration of a wireless communication system (2). This figure shows an example of channel configuration for a downlink using DSS. This figure shows an example (1) of PDCCH reception in an embodiment of the present invention. This figure shows an example (2) of PDCCH reception in an embodiment of the present invention. This figure shows an example (3) of PDCCH reception in an embodiment of the present invention. This is a sequence diagram illustrating an example of PDCCH reception in an embodiment of the present invention. This figure shows an example of the functional configuration of a base station 10 according to an embodiment of the present invention. This figure shows an example of the functional configuration of a terminal 20 according to an embodiment of the present invention. This figure shows an example of the hardware configuration of a base station 10 or terminal 20 according to an embodiment of the present invention. This figure shows an example of the configuration of a vehicle 2001 in an embodiment of the present invention.

The embodiments of the present invention will be described below with reference to the drawings. Note that the embodiments described below are examples, and the embodiments to which the present invention is applied are not limited to the embodiments described below.

In the operation of the wireless communication system according to the embodiment of the present invention, existing technologies will be used as appropriate. However, such existing technologies include, for example, existing LTE, but are not limited to existing LTE. Furthermore, the term "LTE" as used herein has a broad meaning that includes LTE-Advanced and LTE-Advanced and later technologies (e.g., NR), unless otherwise specified.

Furthermore, in the embodiments of the present invention described below, terms such as SS (Synchronization signal), PSS (Primary SS), SSS (Secondary SS), PBCH (Physical broadcast channel), PRACH (Physical random access channel), PDCCH (Physical Downlink Control Channel), PDSCH (Physical Downlink Shared Channel), PUCCH (Physical Uplink Control Channel), and PUSCH (Physical Uplink Shared Channel), which are used in existing LTE systems, will be used. This is for convenience of description, and similar signals, functions, etc., may be called by other names. Also, the above terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, etc. However, even if a signal is used in NR, it is not necessarily explicitly stated as "NR-".

Furthermore, in the embodiments of the present invention, the duplex system may be a TDD (Time Division Duplex) system, an FDD (Frequency Division Duplex) system, or any other system (for example, a Flexible Duplex).

Furthermore, in the embodiments of the present invention, "configuring" wireless parameters, etc., may mean that predetermined values are pre-configured, or that wireless parameters notified from the base station 10 or terminal 20 are configured.

Figure 1 shows an example configuration (1) of a wireless communication system according to an embodiment of the present invention. The wireless communication system according to the embodiment of the present invention includes a base station 10 and a terminal 20, as shown in Figure 1. Although Figure 1 shows one base station 10 and one terminal 20, this is an example, and there may be multiple base stations 10 and terminals 20.

Base station 10 is a communication device that provides one or more cells and communicates wirelessly with terminal 20. The physical resources of the wireless signal are defined in the time domain and the frequency domain. The time domain may be defined by the number of OFDM (Orthogonal Frequency Division Multiplexing) symbols, and the frequency domain may be defined by the number of subcarriers or resource blocks. Base station 10 transmits synchronization signals and system information to terminal 20. Synchronization signals are, for example, NR-PSS and NR-SSS. System information is transmitted, for example, in NR-PBCH and is also called broadcast information. Synchronization signals and system information may also be called SSB (SS/PBCH block). As shown in Figure 1, base station 10 transmits control signals or data to terminal 20 via DL (Downlink) and receives control signals or data from terminal 20 via UL (Uplink). Both base station 10 and terminal 20 are capable of transmitting and receiving signals using beamforming. Furthermore, both the base station 10 and the terminal 20 can apply MIMO (Multiple Input Multiple Output) communication to DL or UL. Also, both the base station 10 and the terminal 20 may communicate via Carrier Aggregation (CA) through secondary cells (SCell) and primary cells (PCell). Additionally, the terminal 20 may communicate via Dual Connectivity (DC) through the primary cell of base station 10 and the primary secondary cell group cell (PSCell) of another base station 10.

Terminal 20 is a communication device equipped with wireless communication capabilities, such as a smartphone, mobile phone, tablet, wearable device, or M2M (Machine-to-Machine) communication module. As shown in Figure 1, Terminal 20 receives control signals or data from the base station 10 via DL and transmits control signals or data to the base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system. Terminal 20 also receives various reference signals transmitted from the base station 10 and performs propagation path quality measurement based on the reception results of said reference signals.

Terminal 20 is capable of performing carrier aggregation, which involves bundling multiple cells (multiple CCs (Component Carriers)) together to communicate with base station 10. Carrier aggregation uses one PCell (Primary cell) and one or more SCells (Secondary cells). Alternatively, a PUCCH-SCell with a PUCCH may be used.

Figure 2 shows an example (2) of a wireless communication system according to an embodiment of the present invention. Figure 2 shows an example of the configuration of a wireless communication system when DC (Dual connectivity) is performed. As shown in Figure 2, a base station 10A that will be an MN (Master Node) and a base station 10B that will be an SN (Secondary Node) are provided. Base stations 10A and 10B are each connected to the core network. Terminal 20 can communicate with both base station 10A and base station 10B.

The cell group provided by base station 10A, which is the MN (Mobile Network), is called the MCG (Master Cell Group), and the cell group provided by base station 10B, which is the SN (Station Network), is called the SCG (Secondary Cell Group). In a data center, an MCG consists of one PCell and one or more SCells, and an SCG consists of one PSCell (Primary SCG Cell) and one or more SCells.

The processing operations in this embodiment may be performed using the system configuration shown in Figure 1, the system configuration shown in Figure 2, or any other system configuration.

The following describes an example of DSS (Dynamic Spectrum Sharing) technology, which allows LTE and NR to coexist within the same band. DSS technology enables flexible response to traffic demands during system generation transitions by allowing different RATs (Radio Access Technologies) to coexist on a single carrier.

Figure 3 shows an example of channel arrangement for a downlink using DSS. The time domain shown in Figure 3 corresponds to one LTE subframe. As shown in Figure 3, "LTE-CRS (Cell specific reference signal)" and "LTE-PDCCH" are transmitted as LTE signals or channels in the downlink. Also, as shown in Figure 3, "NR-PDCCH", "NR-PDSCH DM-RS (Demodulation reference signal)", and "NR-PDSCH" are transmitted as NR channels in the downlink. For example, as shown in Figure 3, "LTE-CRS" may be placed adjacent to "NR-PDSCH". Also, although not shown, the "NR-PDCCH region" may include resources where DM-RS for decoding PDCCH is placed.

In the current DSS, LTE-CRS is transmitted every subframe. When the NR side signal is transmitted over the RE (Resource Element) of LTE-CRS, the characteristics of the LTE system, such as channel estimation or RRM (Radio Resource Management), deteriorate significantly. Therefore, the NR side is designed to avoid LTE-CRS and use the remaining resources. As a result, it has been difficult to secure sufficient resources for NR-PDCH.

Therefore, in DSS, NR-PDCCH reception on symbols where LTE-CRS is located (for example, symbol #1 in Figure 3) is being considered. The method described below is being considered for receiving NR-PDCCH on symbols containing LTE-CRS.

Figure 4 shows an example (1) of PDCCH reception in an embodiment of the present invention. As shown in Figure 4, the NR-PDCCH and DMRS that overlap with the LTE-CRS of symbol #1 are punctured. For DMRS, only symbols #2 and #3 are used, or the unpunctured DMRS of symbol #1 is also used. The method of PDCCH reception described using Figure 4 is referred to as Method 1-1.

Figure 5 shows an example (2) of PDCCH reception in an embodiment of the present invention. As shown in Figure 5, the NR-PDCCH and DMRS that overlap with the LTE-CRS of symbol #1 are punctured, the DMRS is not mapped to symbol #1, and the unmapped resources are used for PDCCH. The method of PDCCH reception described using Figure 5 is referred to as Method 1-2.

Figure 6 shows an example (3) of PDCCH reception in an embodiment of the present invention. As shown in Figure 6, the NR-PDCCH and DMRS of the resource to which the LTE-CRS is mapped are multiplexed and transmitted as is without puncturing. The method of PDCCH reception described using Figure 6 is referred to as Method 2.

In the existing specifications, terminal 20 is not required to monitor PDCCH candidates that overlap with symbols including LTE-CRS (see, for example, Non-Patent Document 4). On the other hand, the network needs to know whether or not a terminal is capable of monitoring PDCCH candidates that overlap with LTE-CRS.

Furthermore, since there are multiple ways to receive NR-PDCCH on a symbol in LTE-CRS, it is necessary to ensure that the method applied by terminal 20 and the network are consistent.

Therefore, terminal 20 may report to the network via its UE capability whether it is able to receive NR-PDCCH candidates that include OFDM symbols for which LTE-CRS symbols are transmitted. Furthermore, if multiple methods are specified, terminal 20 may report to the network via its UE capability which method it is able to support.

The terminal 20 that reported the above UE capability may monitor PDCCH candidates that overlap with symbols including LTE-CRS if the network has configured information of at least one or a specific combination of 1)-4) shown below by RRC signaling.

1) When a rate matching pattern for four CRS ports is set for the serving cell in question.
2) When a CRS pattern is set in the serving cell for a function that monitors PDCCH candidates that overlap with symbols including CRS, separate from the rate matching function.
3) When a PDCCH CORESET and/or search space is set that overlaps with a symbol containing CRS.
4) When a specific new Information Element (IE) is set. For example, when an IE is set that enables the function to monitor PDCCH candidates that overlap with symbols containing CRS.

Figure 7 is a sequence diagram illustrating an example of PDCCH reception in an embodiment of the present invention. In step S11, terminal 20 transmits UE capability to base station 10 indicating whether it is possible to receive NR-PDCCH candidates that include OFDM symbols on which LTE-CRS symbols are transmitted. In the following step S12, terminal 20 receives the specific RRC signaling described above. In the following step S13, terminal 20 monitors PDCCH candidates that overlap with symbols including LTE-CRS.

Even if the above-mentioned specific RRC signaling is received, if the CORESET and/or search space is a specific CORESET and/or search space, or if it is not a specific CORESET and/or search space, terminal 20 does not need to monitor PDCCH candidates that overlap with symbols including CRS, nor does it need to assume that such a case will be set. The specific CORESET and/or search space may be, for example, CORESET0 and/or SS0 (Search Space 0), or the common search space.

If multiple methods are specified for receiving NR-PDCCH candidates, including OFDM symbols to which LTE-CRS symbols are transmitted, terminal 20 may report which method it supports through its UE capabilities, or the network may configure which method to enable through RRC signaling.

Terminal 20 may change the assumption regarding the mapping of symbols including CRS to NR-PDCCH and/or DMRS, and whether or not puncturing occurs, depending on which method is enabled.

For example, if method 1-1 above is enabled, terminal 20 is assumed to be punctured by symbols including CRS, specifically NR-PDCCH and DMRS that overlap with CRS.

For example, if method 1-2 above is enabled, terminal 20 will not map DMRS with symbols including CRS, but will instead map NR-PDCCH, and it is assumed that NR-PDCCH overlapping with CRS will be punctured.

For example, if method 2 above is enabled, terminal 20 does not assume that NR-PDCCH and DMRS, which overlap with CRS, will be punctured by symbols containing CRS.

Conditions may be defined for enabling the function to monitor PDCCH candidates that overlap with symbols containing CRS. Furthermore, conditions may be defined for enabling specific methods applied to the function to monitor PDCCH candidates that overlap with symbols containing CRS.

For example, if the PDCCH aggregation level is above or below a certain value, a function to monitor PDCCH candidates that overlap with symbols containing CRS may be enabled, or a specific method applied to said function may be enabled. Furthermore, whether this function or the specific method can be enabled above or below a certain aggregation level may be reported in the UE capability.

For example, if no CORESET and/or PDCCH candidates are set that span multiple CRS patterns (especially when referring to rate matching patterns), the function to monitor PDCCH candidates that overlap with symbols containing CRS may be enabled, or a specific method for applying such function may be enabled. Alternatively, if CORESET and/or PDCCH candidates are set that span multiple CRS patterns (especially when referring to rate matching patterns), the function to monitor PDCCH candidates that overlap with symbols containing CRS may not be enabled, or even in such cases, whether or not it can be enabled may be reported in the UE capability.

As described above, in the LTE and NR DSS scenarios, the capacity of the NR-PDCCH can be increased by enabling the transmission and reception of NR-PDCCH on the symbol where the LTE-CRS is located.

In other words, in a wireless communication system, it is possible to secure control signal resources when multiple RATs (Radio Access Technologies) coexist on a single carrier.

(Device configuration)
Next, an example of the functional configuration of the base station 10 and terminal 20 that perform the processes and operations described above will be explained. The base station 10 and terminal 20 include functions to carry out the embodiments described above. However, the base station 10 and terminal 20 may each be equipped with only some of the functions in the embodiments.

<Base station 10>
Figure 8 shows an example of the functional configuration of a base station 10 in an embodiment of the present invention. As shown in Figure 8, the base station 10 has a transmitting unit 110, a receiving unit 120, a setting unit 130, and a control unit 140. The functional configuration shown in Figure 8 is merely an example. Any functional classification and functional unit names are acceptable as long as they can perform the operations according to the embodiment of the present invention.

The transmitting unit 110 includes the function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The transmitting unit 110 also transmits inter-network node messages to other network nodes. The receiving unit 120 includes the function of receiving various signals transmitted from the terminal 20 and obtaining information from the received signals, for example, higher layer information. The transmitting unit 110 also has the function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL/UL control signals, etc. to the terminal 20. The receiving unit 120 also receives inter-network node messages from other network nodes.

The setting unit 130 stores pre-configured setting information and various setting information to be transmitted to the terminal 20. The content of the setting information includes, for example, information related to DSS.

The control unit 140 performs control related to the DSS, as described in the embodiment. The signal transmission function in the control unit 140 may be included in the transmission unit 110, and the signal reception function in the control unit 140 may be included in the reception unit 120.

<Terminal 20>
Figure 9 shows an example of the functional configuration of a terminal 20 in an embodiment of the present invention. As shown in Figure 9, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. The functional configuration shown in Figure 9 is merely an example. Any functional classification and functional unit names are acceptable as long as they can perform the operations according to the embodiment of the present invention.

The transmitting unit 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiving unit 220 wirelessly receives various signals and acquires signals from higher layers from the received physical layer signals. The receiving unit 220 also has the function of receiving NR-PSS, NR-SSS, NR-PBCH, DL/UL/SL control signals, etc. transmitted from the base station 10. For example, the transmitting unit 210 transmits PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), PSDCH (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel), etc. to other terminals 20 as D2D communication, and the receiving unit 220 receives PSCCH, PSSCH, PSDCH or PSBCH, etc. from other terminals 20.

The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220. The setting unit 230 also stores pre-configured setting information. The content of the setting information includes, for example, information related to DSS (Digital Security System).

The control unit 240 performs control related to the DSS, as described in the embodiment. The signal transmission function in the control unit 240 may be included in the transmission unit 210, and the signal reception function in the control unit 240 may be included in the reception unit 220.

(Hardware configuration)
The block diagrams (Figures 8 and 9) used in the description of the above embodiments show functional units. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or it may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wired or wireless connections). A functional block may also be realized by combining software with the one or more of the above devices.

Functions include, but are not limited to, judgment, decision, judgment, calculation, calculation, processing, derivation, investigation, exploration, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, assumption, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating (mapping), and assigning. For example, a functional block (configuration part) that enables transmission is called a transmitting unit or transmitter. As mentioned above, the method of implementation is not particularly limited.

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

In the following explanation, the term "device" can be replaced with "circuit," "device," "unit," etc. The hardware configuration of the base station 10 and terminal 20 may include one or more of the devices shown in the figure, or it may be configured without some of the devices.

Each function in the base station 10 and terminal 20 is realized by loading predetermined software (programs) onto hardware such as the processor 1001 and storage device 1002, which allows the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of the reading and writing of data in the storage device 1002 and auxiliary storage device 1003.

The processor 1001 controls the entire computer, for example, by running the operating system. The processor 1001 may consist of a central processing unit (CPU) including interfaces with peripheral devices, control devices, arithmetic units, registers, etc. For example, the control unit 140, control unit 240, etc., described above may be implemented by the processor 1001.

Furthermore, the processor 1001 reads programs (program code), software modules, or data from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes accordingly. The program used is one that causes the computer to execute at least a part of the operations described in the above-described embodiment. For example, the control unit 140 of the base station 10 shown in Figure 8 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Similarly, the control unit 240 of the terminal 20 shown in Figure 9 may be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. While the above-described processes have been explained as being executed by a single processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may also be transmitted from the network via a telecommunications line.

The storage device 1002 is a computer-readable recording medium and may consist of at least one of the following: ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), RAM (Random Access Memory), etc. The storage device 1002 may also be called a register, cache, main memory, etc. The storage device 1002 can store executable programs (program code), software modules, etc., for implementing a communication method according to one embodiment of this disclosure.

The auxiliary storage device 1003 is a computer-readable recording medium and may consist of at least one of the following: an optical disc such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital multipurpose disk, a Blu-ray® disk), a smart card, flash memory (e.g., a card, a stick, a key drive), a floppy® disk, a magnetic strip, etc. The above-mentioned storage medium may also be a database, server, or other suitable medium that includes at least one of the storage device 1002 and the auxiliary storage device 1003.

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, communication module, etc. The communication device 1004 may include, for example, 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 transmitting/receiving antenna, amplifier section, transmitting/receiving section, transmission path interface, etc., may be implemented by the communication device 1004. The transmitting/receiving section may be physically or logically separated into a transmitting section and a receiving section.

The input device 1005 is an input device that accepts input from an external source (e.g., a keyboard, mouse, microphone, switch, button, sensor, etc.). The output device 1006 is an output device that outputs to an external source (e.g., a display, speaker, LED lamp, etc.). The input device 1005 and the output device 1006 may be configured as an integrated unit (e.g., a touch panel).

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

Furthermore, the base station 10 and terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array), and some or all of each functional block may be realized by such hardware. For example, the processor 1001 may be implemented using at least one of these hardware components.

Figure 11 shows an example of the configuration of vehicle 2001. As shown in Figure 11, vehicle 2001 includes a drive unit 2002, a steering unit 2003, an accelerator pedal 2004, a brake pedal 2005, a shift lever 2006, front wheels 2007, rear wheels 2008, an axle 2009, an electronic control unit 2010, various sensors 2021 to 2029, an information service unit 2012, and a communication module 2013. Each aspect/embodiment described in this disclosure may be applied to a communication device mounted on vehicle 2001, for example, to the communication module 2013.

The drive unit 2002 consists, for example, an engine, a motor, or a hybrid of an engine and a motor. The steering unit 2003 includes at least a steering wheel (also called a handle) and is configured to steer at least one of the front wheels and the rear wheels based on the operation of the steering wheel, which is operated by the user.

The electronic control unit 2010 consists of a microprocessor 2031, memory (ROM, RAM) 2032, and communication ports (IO ports) 2033. Signals from various sensors 2021 to 2029 installed in the vehicle 2001 are input to the electronic control unit 2010. The electronic control unit 2010 may also be called an ECU (Electronic Control Unit).

Signals from various sensors 2021 to 2029 include current signals from the current sensor 2021 which senses the motor current, front and rear wheel rotation speed signals obtained by the rotation speed sensor 2022, front and rear wheel air pressure signals obtained by the air pressure sensor 2023, vehicle speed signals obtained by the vehicle speed sensor 2024, acceleration signals obtained by the acceleration sensor 2025, accelerator pedal depression signals obtained by the accelerator pedal sensor 2029, brake pedal depression signals obtained by the brake pedal sensor 2026, shift lever operation signals obtained by the shift lever sensor 2027, and detection signals obtained by the object detection sensor 2028 for detecting obstacles, vehicles, pedestrians, etc.

The Information Service Unit 2012 consists of various devices for providing (outputting) various types of information such as driving information, traffic information, and entertainment information, including a car navigation system, audio system, speakers, television, and radio, and one or more ECUs that control these devices. The Information Service Unit 2012 uses information acquired from external devices via a communication module 2013, etc., to provide various multimedia information and multimedia services to the occupants of the vehicle 2001. The Information Service Unit 2012 may include input devices that accept input from the outside (e.g., keyboard, mouse, microphone, switch, button, sensor, touch panel, etc.) and output devices that perform output to the outside (e.g., display, speaker, LED lamp, touch panel, etc.).

The driver assistance system unit 2030 consists of various devices that provide functions to prevent accidents or reduce the driver's workload, such as millimeter-wave radar, LiDAR (Light Detection and Ranging), cameras, positioning locators (e.g., GNSS), map information (e.g., high-definition (HD) maps, autonomous vehicle (AV) maps), gyro systems (e.g., IMU (Inertial Measurement Unit), INS (Inertial Navigation System)), AI (Artificial Intelligence) chips, and AI processors, as well as one or more ECUs that control these devices. Furthermore, the driver assistance system unit 2030 transmits and receives various information via the communication module 2013 to realize driver assistance functions or autonomous driving functions.

The communication module 2013 can communicate with the microprocessor 2031 and components of the vehicle 2001 via its communication port. For example, the communication module 2013 sends and receives data via the communication port 2033 between the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axle 2009, the microprocessor 2031 and memory (ROM, RAM) 2032 in the electronic control unit 2010, and sensors 2021-29 provided in the vehicle 2001.

The communication module 2013 is a communication device that can be controlled by the microprocessor 2031 of the electronic control unit 2010 and can communicate with external devices. For example, it can send and receive various types of information with external devices via wireless communication. The communication module 2013 may be located either inside or outside the electronic control unit 2010. The external device may be, for example, a base station, a mobile station, etc.

The communication module 2013 may transmit at least one of the following to an external device via wireless communication: signals from the various sensors 2021-2028 input to the electronic control unit 2010, information obtained based on said signals, and information based on input from an external source (user) obtained via the information service unit 2012. The electronic control unit 2010, the various sensors 2021-2028, the information service unit 2012, etc., may also be called input units that accept input. For example, the PUSCH transmitted by the communication module 2013 may include the information based on the above input.

The communication module 2013 receives various information (traffic information, signal information, inter-vehicle information, etc.) transmitted from an external device and displays it on the information service unit 2012 provided in the vehicle 2001. The information service unit 2012 may also be called an output unit, which outputs information (for example, outputs information to devices such as displays and speakers based on the PDSCH (or data/information decoded from the PDSCH) received by the communication module 2013). The communication module 2013 also stores the various information received from the external device in a memory 2032 that can be used by the microprocessor 2031. Based on the information stored in the memory 2032, the microprocessor 2031 may control the drive unit 2002, steering unit 2003, accelerator pedal 2004, brake pedal 2005, shift lever 2006, front wheels 2007, rear wheels 2008, axles 2009, sensors 2021-2029, etc., provided in the vehicle 2001.

(Summary of the embodiments)
As described above, according to an embodiment of the present invention, a terminal is provided which includes a transmitting unit that transmits to the network information indicating whether or not a candidate downlink control channel for the second RAT, including a symbol on which the reference signal of the first RAT is located, can be received when the first RAT (Radio Access Technology) and the second RAT are operated on the same band; a receiving unit that receives RRC (Radio Resource Control) signaling from the network; and a control unit that monitors the candidate downlink control channel, including the symbol, when the RRC signaling is a specific signaling.

With the above configuration, in LTE and NR DSS scenarios, the capacity of NR-PDCCH can be increased by enabling the transmission and reception of NR-PDCCH on the symbol where LTE-CRS is located. In other words, in a wireless communication system, it is possible to secure control signal resources when multiple RATs (Radio Access Technologies) coexist on a single carrier.

The control unit may monitor the downlink control channel candidates, including the symbol, when the RRC signaling sets a rate matching pattern for the four-port first RAT reference signal on the serving cell. This configuration allows for increased NR-PDCCH capacity in LTE and NR DSS scenarios by enabling NR-PDCCH transmission and reception on the symbol where the LTE-CRS is located.

The control unit may monitor the downlink control channel candidates, including the symbol, when setting the downlink control channel CORESET (Control Resource Set) and/or search space in which the RRC signaling overlaps with the symbol. This configuration allows for increased NR-PDCCH capacity in LTE and NR DSS scenarios by enabling NR-PDCCH transmission and reception on the symbol where the LTE-CRS is located.

The control unit does not need to monitor the downlink control channel candidate including the symbol if the RRC signaling is the specific signaling and the CORESET of the downlink control channel overlapping the symbol is the specific CORESET. With this configuration, in LTE and NR DSS scenarios, the transmission and reception of NR-PDCCH on the symbol where LTE-CRS is located can be disabled in specific cases.

The control unit may enable a function to monitor the downlink control channel candidates, including the symbol, when the aggregation level of the downlink control channel is above or below a threshold. This configuration allows for increased NR-PDCCH capacity in LTE and NR DSS scenarios by enabling NR-PDCCH transmission and reception on the symbol where the LTE-CRS is located.

Furthermore, according to an embodiment of the present invention, when a first RAT (Radio Access Technology) and a second RAT are operating on the same band, a communication method is provided in which a terminal performs the following steps: a procedure to transmit information to the network indicating whether or not a candidate downlink control channel for the second RAT, which includes a symbol on which the reference signal of the first RAT is located, is receivable; a procedure to receive RRC (Radio Resource Control) signaling from the network; and, if the RRC signaling is a specific signaling, a procedure to monitor the candidate downlink control channel, which includes the symbol.

With the above configuration, in LTE and NR DSS scenarios, the capacity of NR-PDCCH can be increased by enabling the transmission and reception of NR-PDCCH on the symbol where LTE-CRS is located. In other words, in a wireless communication system, it is possible to secure control signal resources when multiple RATs (Radio Access Technologies) coexist on a single carrier.

(Supplement to the embodiment)
While embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, substitutions, etc. Specific numerical examples have been used to facilitate understanding of the invention, but unless otherwise specified, these numerical values are merely examples, and any appropriate values may be used. The division of items in the above description is not essential to the present invention; matters described in two or more items may be combined as needed, and matters described in one item may be applied to matters described in another item (as long as they do not contradict each other). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operation of multiple functional units may be physically performed by one part, or the operation of one functional unit may be physically performed by multiple parts. Regarding the processing procedures described in the embodiments, the order of processing may be changed as long as it does not contradict each other. For the convenience of explaining the processing, the base station 10 and terminal 20 have been described using functional block diagrams, but such devices may be implemented in hardware, software, or a combination thereof. The software operated by the processor of the base station 10 according to an embodiment of the present invention and the software operated by the processor of the terminal 20 according to an embodiment of the present invention may be stored in any suitable storage medium such as random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or other appropriate storage medium.

Furthermore, notification of information is not limited to the embodiments/models described herein and may be carried out by other methods. For example, notification of information may be carried out by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), upper layer signaling (e.g., RRC (Radio Resource Control) signaling, MAC (Medium Access Control) signaling), broadcast information (MIB (Master Information Block), SIB (System Information Block)), other signals, or combinations thereof. Also, RRC signaling may be called RRC messages, and may be, for example, RRC Connection Setup messages, RRC Connection Reconfiguration messages, etc.

Each aspect/embodiment described in this disclosure is LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), 6th generation mobile communication system (6G), xth generation mobile communication system (xG) (xG (where x is, for example, an integer or decimal)), FRA (Future Radio Access), NR (new Radio), New radio access (NX), Future generation radio access (FX), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20 may apply to at least one system utilizing UWB (Ultra-WideBand), Bluetooth®, or other appropriate systems, and to next-generation systems extended, modified, created, or defined based thereon. Alternatively, multiple systems may be applied in combination (e.g., a combination of at least one of LTE and LTE-A with 5G).

The processing procedures, sequences, flowcharts, etc., of each aspect/embodiment described herein may be reordered, provided they are consistent. For example, the methods described herein present various step elements in an exemplary order and are not limited to that specific order.

In this specification, specific operations performed by the base station 10 may, in some cases, be performed by its upper node. In a network consisting of one or more network nodes having a base station 10, it is clear that various operations performed for communication with the terminal 20 can be performed by the base station 10 and at least one other network node (for example, an MME or S-GW, but not limited to these). While the above example illustrates a case where there is one other network node besides the base station 10, the other network node may be a combination of multiple other network nodes (for example, an MME and an S-GW).

The information or signals described in this disclosure may be output from a higher layer (or lower layer) to a lower layer (or higher layer). They may also be input and output via multiple network nodes.

Input and output information may be stored in a specific location (e.g., memory) or managed using a management table. Input and output information may be overwritten, updated, or appended to. Output information may be deleted. Input information may be transmitted to other devices.

The determination in this disclosure may be made by a value represented by one bit (0 or 1), by a Boolean value (true or false), or by a numerical comparison (for example, a comparison with a predetermined value).

Software, whether called software, firmware, middleware, microcode, hardware description language, or by any other name, should be interpreted 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, execution threads, procedures, functions, and so on.

Furthermore, software, instructions, information, etc., may be transmitted and received via a transmission medium. For example, if software is transmitted from a website, server, or other remote source using at least one of wired technologies (such as coaxial cable, fiber optic cable, twisted pair, or digital subscriber line (DSL)) and wireless technologies (such as infrared or microwave), then at least one of these wired and wireless technologies is included in the definition of a transmission medium.

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

Furthermore, terms used in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of the channel and symbol may be a signal (signaling). Also, a signal may be a message. Also, a component carrier (CC) may be called a carrier frequency, cell, frequency carrier, etc.

The terms “system” and “network” as used in this disclosure are interchangeable.

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

The names used for the parameters described above are not restrictive in any way. Furthermore, the formulas and other expressions using these parameters may differ from those expressly disclosed in this disclosure. Various channels (e.g., PUCCH, PDCCH, etc.) and information elements can be identified by any suitable name, and therefore, the various names assigned to these various channels and information elements are not restrictive in any way.

In this disclosure, terms such as “Base Station (BS),” “wireless base station,” “base station equipment,” “fixed station,” “NodeB,” “eNodeB (eNB),” “gNodeB (gNB),” “access point,” “transmission point,” “reception point,” “transmission/reception point,” “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 may house one or more (e.g., three) cells. If a base station houses multiple cells, the entire coverage area of the base station may be divided into several smaller areas, each of which may also be provided with communication services by a base station subsystem (e.g., a Remote Radio Head (RRH)). The terms "cell" or "sector" refer to part or all of the coverage area of at least one of the base station and/or base station subsystems providing communication services in that coverage.

In this disclosure, the transmission of information by a base station to a terminal may be interpreted as the base station instructing the terminal to perform control or operation based on the information.

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 by those skilled in the art 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 several other appropriate terms.

At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may also be a device mounted on a mobile body, the mobile body itself, etc. The mobile body refers to a movable object, and its speed of movement is arbitrary. This also includes the case when the mobile body is stationary. The mobile body includes, but is 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 (registered trademark), multicopters, quadcopters, balloons, and items mounted on them. The mobile body may also be a mobile body that moves autonomously based on operation commands. It may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Furthermore, at least one of the base station and the mobile station may 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 IoT (Internet of Things) device such as a sensor.

Furthermore, the term "base station" in this disclosure may be interpreted as "user terminal." For example, the various aspects/embodiments of this disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple terminals 20 (which may be called, for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, the terminals 20 may have the functions that the base station 10 has. Also, terms such as "uplink" and "downlink" may be interpreted as terms corresponding to inter-terminal communication (for example, "side"). For example, uplink channel, downlink channel, etc., may be interpreted as side channel.

Similarly, the term "user terminal" in this disclosure may be replaced with "base station." In this case, the base station may be configured to have the functions that the user terminal has.

The terms “determining” and “determining” as used in this disclosure may encompass a wide variety of actions. “Determining” and “determining” may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, or inquiring (e.g., searching in a table, database, or other data structure), or ascertaining. “Determining” and “determining” may also include receiving (e.g., receiving information), transmitting (e.g., sending information), inputting, outputting, or accessing (e.g., accessing data in memory). Furthermore, "judgment" and "decision" can include considering something as having been "judged" or "decided" after resolving, selecting, choosing, establishing, comparing, etc. In other words, "judgment" and "decision" can include considering something as having been "judged" or "decided" after some action. Also, "judgment (decision)" can be reinterpreted as "assuming," "expecting," or "considering."

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” with each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, “connection” may be reinterpreted as “access.” As used in this disclosure, two elements may be considered to be “connected” or “coupled” with each other using at least one of one or more wires, cables, and printed electrical connections, and, in some non-limiting and non-exclusive examples, electromagnetic energy having wavelengths in the radio frequency domain, microwave domain, and optical (both visible and invisible) domain.

The reference signal can also be abbreviated as RS (Reference Signal), and may be called the pilot depending on the applicable standard.

In this disclosure, the phrase "based on" does not mean "based solely on" unless otherwise specified. In other words, the phrase "based on" means both "based solely on" and "based at least on."

Any reference to elements using the designations “first,” “second,” etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Therefore, references to the first and second elements do not imply that only two elements may be employed, or that the first element must precede the second element in any way.

In the configuration of each of the above devices, "means" may be replaced with "part," "circuit," "device," etc.

Where the terms “include,” “including,” and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term “comprising.” Furthermore, the term “or” as used in this disclosure is not intended to be exclusive OR.

A wireless frame may consist of one or more frames in the time domain. Each of these frames in the time domain may be called a subframe. A subframe may further consist 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.

Numerical logic may be communication parameters applied to at least one of the transmission and reception of a signal or channel. Numerical logic may include, for example, at least one of the following: subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame configuration, specific filtering processes performed by the transceiver in the frequency domain, and specific windowing processes performed by the transceiver in the time domain.

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

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

Wireless frames, subframes, slots, minislots, and symbols all represent units of time when transmitting a signal. Different names may be used for each of these terms.

For example, one subframe may be called a Transmission Time Interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one mini-slot may be called a TTI. In other words, at least one of a subframe and a TTI may be a subframe in existing LTE (1 ms), a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, mini-slot, 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, the base station schedules each terminal 20 to allocate wireless resources (such as the frequency bandwidth and transmission power available to each terminal 20) in TTI units. However, the definition of TTI is not limited to this.

The Time Time Increment (TTI) may be a transmission time unit for channel-encoded data packets (transport blocks), code blocks, code words, etc., or it may be a processing unit for scheduling, link adaptation, etc. Note that, given a TTI, the actual time interval (e.g., number of symbols) to which the transport block, code block, code word, etc., are mapped may be shorter than the TTI.

Furthermore, if one slot or one mini-slot is referred to as a TTI, then one or more TTIs (i.e., one or more slots or one or more mini-slots) may constitute the minimum time unit for scheduling. Also, the number of slots (number of mini-slots) constituting this minimum time unit for scheduling may be controlled.

A TTI with a time length of 1 ms may be called a normal TTI, long TTI, normal subframe, long subframe, slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, mini slot, sub slot, slot, etc.

Furthermore, long TTIs (e.g., normal TTIs, subframes, etc.) may be interpreted as TTIs with a time length exceeding 1 ms, and short TTIs (e.g., shortened TTIs, etc.) may be interpreted as TTIs with a TTI length less than that of a long TTI but 1 ms or more.

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

Furthermore, the time domain of the RB may contain one or more symbols and may be the length of one slot, one mini-slot, one subframe, or one TTI. One TTI, one subframe, etc., may each consist of one or more resource blocks.

Furthermore, one or more RBs may also be called a Physical RB (PRB), Sub-Carrier Group (SCG), Resource Element Group (REG), PRB pair, RB pair, etc.

Furthermore, a resource block may consist of one or more resource elements (REs). For example, one RE may be a radio resource area comprising one subcarrier and one symbol.

A Bandwidth Part (BWP), also known as a partial bandwidth, may represent a subset of consecutive common resource blocks (RBs) for a particular neurology in a given carrier. Here, the common RBs may be identified by an index of the RBs relative to the carrier's common reference point. The PRBs may be defined and numbered within a given BWP.

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

At least one of the configured BWPs may be active, and the UE does not need to assume that it will transmit or receive a predetermined signal/channel outside of the active BWP. In this disclosure, terms such as "cell" and "carrier" may be interpreted as "BWP".

The structures described above, such as wireless frames, subframes, slots, minislots, and symbols, are merely illustrative. For example, the number of subframes included in a wireless frame, the number of slots per subframe or wireless 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, and the number of symbols, symbol length, and cyclic prefix (CP) length within the TTI can be varied in various ways.

In this disclosure, if articles are added through translation, such as a, an, and the in English, this disclosure may include the fact that the noun following these articles is plural.

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 "combine" may be interpreted similarly to "different."

Each aspect/embodiment described in this disclosure may be used individually, in combination, or switched between as needed during implementation. Furthermore, notification of specific information (e.g., notification that "X is X") is not limited to explicit notification, but may also be implicit (e.g., by not providing such notification).

Although the present disclosure has been described in detail above, it will be clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the intent and scope of the present disclosure as defined by the claims. Therefore, the descriptions in the present disclosure are illustrative and not intended to be restrictive in any way.
(Section 1)
When a first RAT (Radio Access Technology) and a second RAT are operating on the same band, a transmitting unit transmits to the network information indicating whether or not a candidate downlink control channel for the second RAT, which includes a symbol on which the reference signal of the first RAT is located, is receivable.
A receiving unit that receives RRC (Radio Resource Control) signaling from the network,
A terminal having a control unit that monitors the downlink control channel candidates, including the symbol, when the RRC signaling is a specific signaling.
(Section 2)
The terminal according to paragraph 1, wherein the control unit monitors the downlink control channel candidates, including the symbols, when the RRC signaling sets a rate matching pattern for the reference signals of the four ports of the first RAT in the serving cell.
(Section 3)
The terminal according to paragraph 1, which monitors the downlink control channel candidate including the symbol when the control unit sets the downlink control channel CORESET (Control Resource Set) and/or search space in which the RRC signaling overlaps with the symbol.
(Section 4)
The terminal according to paragraph 1, wherein the control unit does not monitor the downlink control channel candidate including the symbol when the RRC signaling is the specific signaling and the CORESET of the downlink control channel overlapping with the symbol is the specific CORESET.
(Section 5)
The terminal according to paragraph 1, wherein the control unit enables a function to monitor the downlink control channel candidates, including the symbol, when the aggregation level of the downlink control channel is above or below a threshold.
(Section 6)
When a first RAT (Radio Access Technology) and a second RAT are operating on the same band, a procedure for transmitting information to the network indicating whether or not a candidate downlink control channel for the second RAT, which includes a symbol on which the reference signal of the first RAT is located, is receivable;
The procedure for receiving RRC (Radio Resource Control) signaling from the network,
A communication method in which a terminal performs the steps of monitoring downlink control channel candidates including the symbol if the RRC signaling is a specific signaling.

10 Base station 110 Transmitting unit 120 Receiving unit 130 Setting unit 140 Control unit 20 Terminal 210 Transmitting unit 220 Receiving unit 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device 2001 Vehicle 2002 Drive unit 2003 Steering unit 2004 Accelerator pedal 2005 Brake pedal 2006 Shift lever 2007 Front wheel 2008 Rear wheel 2009 Axle 2010 Electronic control unit 2012 Information service unit 2013 Communication module 2021 Current sensor 2022 Rotation speed sensor 2023 Air pressure sensor 2024 Vehicle speed sensor 2025 Acceleration sensor 2026 Brake pedal sensor 2027 Shift lever sensor 2028 Object detection sensor 2029 Accelerator pedal sensor 2030, driver assistance system unit 2031, microprocessor 2032, memory (ROM, RAM)
2033 Communication port (I/O port)

Claims (3)

A receiving unit that receives RRC (Radio Resource Control) signaling from the network, which includes first information that enables monitoring of a candidate downlink control channel for a second RAT, which includes a resource element on which a reference signal for a first RAT (Radio Access Technology) is located.
The system includes a control unit that monitors the downlink control channel candidate, which includes the resource element on which the reference signal is located, based on the first information in the RRC signaling,
The device further includes a transmitting unit that transmits terminal capability information to the network, including second information regarding whether or not the downlink control channel candidate of the second RAT, which includes the resource element on which the reference signal of the first RAT is located, is receivable.
The receiving unit receives the RRC signaling including the first information after transmitting the terminal capability information.
The RRC signaling includes a fourth piece of information relating to the pattern of the reference signal,
The control unit monitors the downlink control channel candidate, which includes the resource element on which the reference signal is located, based on the fourth information in the RRC signaling.
The RRC signaling includes a fifth piece of information relating to the search space for the downlink control channel candidate,
The control unit monitors the downlink channel candidate when the downlink channel candidate based on the fifth information overlaps with the resource element based on the fourth information.
Terminal. The terminal capability information includes, in the case where multiple patterns exist for the reference signal, third information regarding whether or not the downlink control channel candidate can be received.
The terminal according to claim 1. A procedure for receiving RRC (Radio Resource Control) signaling from the network, which includes first information that enables monitoring of a candidate downlink control channel for a second RAT, including a resource element where the reference signal for a first RAT (Radio Access Technology) is located, and
A procedure for monitoring the downlink control channel candidate, which includes the resource element on which the reference signal is located, based on the first information in the RRC signaling,
A procedure for transmitting terminal capability information to the network, including second information regarding whether or not the downlink control channel candidate of the second RAT, which includes the resource element on which the reference signal of the first RAT is located, is receivable;
A procedure for receiving the RRC signaling including the first information after transmitting the terminal capability information,
The RRC signaling includes a fourth piece of information relating to the pattern of the reference signal,
A procedure for monitoring the downlink control channel candidate, which includes the resource element on which the reference signal is located, based on the fourth information in the RRC signaling,
The RRC signaling includes a fifth piece of information relating to the search space for the downlink control channel candidate,
When the candidate downlink channel based on the fifth information overlaps with the resource element based on the fourth information, the procedure for monitoring the candidate downlink control channel is as follows:
The communication method used by the terminal.