JP7553200B2 - Terminal and communication method - Google Patents

Description

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

For NR (New Radio) (also known as "5G"), the successor system to LTE (Long Term Evolution), technologies are being considered that meet the requirements of a large-capacity system, high data transmission speed, low latency, simultaneous connection of a large number of terminals, low cost, and low power consumption (for example, non-patent document 1).

In NR Release 16, the MR-DC (Multi-Radio Dual Connectivity)/CA (Carrier Aggregation) enhanced work item supports the secondary cell dormancy indication function (see, for example, Non-Patent Document 2). For the purpose of power saving, a secondary cell or a group of secondary cells is notified of either dormancy or non-dormancy by DCI (Downlink control information) during an active period of DRX (Discontinuous reception). In a secondary cell that is notified of dormancy, for example, the terminal does not monitor the PDCCH (Physical Downlink Control Channel).

3GPP TS 38.300 V16.0.0 (2019-12) 3GPP TS 38.212 V16.0.0 (2019-12)

In MR-DC/CA, transitions to the dormant state of a secondary cell were possible through layer 1 signaling. However, transitions to the active state of a secondary cell could not be set through layer 1 signaling, resulting in delays.

The present invention has been made in consideration of the above points, and aims to reduce delays associated with cell state transitions in wireless communication systems.

According to the disclosed technology, a terminal is provided which has a receiving unit that receives control information, which is Layer 1 signaling including a field that indicates activation or deactivation of one or more secondary cells, from a base station, and a control unit that transitions the one or more secondary cells to an active state or an inactive state for each secondary cell or for each secondary cell group based on the field, and the control unit transitions a secondary cell that is in an inactive state among the one or more secondary cells to an active state when a non-dormant state is notified by the field that indicates a dormant state .

The disclosed technology makes it possible to reduce delays associated with cell state transitions in wireless communication systems.

1 is a diagram illustrating an example of a configuration of a wireless communication system according to an embodiment of the present invention. FIG. 11 is a diagram illustrating an example of control information for changing the state of a cell. FIG. 11 is a diagram for explaining an example of an operation related to a hibernation state. 1 is a sequence diagram for explaining an example of an operation related to a state transition of a cell in an embodiment of the present invention. FIG. FIG. 11 is a diagram showing an example (1) of control information according to an embodiment of the present invention. FIG. 11 is a diagram showing an example (2) of control information according to the embodiment of the present invention. 1 is a flowchart for explaining an example (1) of a cell state transition in an embodiment of the present invention. 11 is a flowchart for explaining an example (2) of a cell state transition in the embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a functional configuration of a base station 10 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal 20 according to an embodiment of the present invention. 2 is a diagram illustrating an example of a hardware configuration of a base station 10 or a terminal 20 according to an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the embodiment described below is an example, and the embodiment to which the present invention is applicable is not limited to the following embodiment.

Existing technology is used as appropriate in the operation of the wireless communication system of the embodiment of the present invention. However, the existing technology is, for example, the existing LTE, but is not limited to the existing LTE. Furthermore, the term "LTE" used in this specification has a broad meaning including LTE-Advanced and systems subsequent to LTE-Advanced (e.g., NR) unless otherwise specified.

In addition, in the embodiment 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) used in existing LTE are used. This is for convenience of description, and similar signals, functions, etc. may be called by other names. In addition, the above-mentioned 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 specified as "NR-".

In addition, in an embodiment of the present invention, the duplex method may be a TDD (Time Division Duplex) method, an FDD (Frequency Division Duplex) method, or another method (e.g., Flexible Duplex, etc.).

In addition, in an embodiment of the present invention, when radio parameters, etc. are "configured," this may mean that predetermined values are pre-configured, or that radio parameters notified from the base station 10 or the terminal 20 are configured.

Figure 1 is a diagram showing an example of the configuration of a wireless communication system in an embodiment of the present invention. As shown in Figure 1, the wireless communication system in the embodiment of the present invention includes a base station 10 and a terminal 20. Although Figure 1 shows one base station 10 and one terminal 20, this is an example and there may be multiple of each.

The base station 10 is a communication device that provides one or more cells and performs wireless communication with the terminal 20. The physical resources of a wireless signal are defined in the time domain and the frequency domain, and 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 the number of resource blocks. The base station 10 transmits a synchronization signal and system information to the terminal 20. The synchronization signal is, for example, NR-PSS and NR-SSS. The system information is, for example, transmitted by NR-PBCH and is also called broadcast information. As shown in FIG. 1, the base station 10 transmits a control signal or data to the terminal 20 in DL (Downlink) and receives a control signal or data from the terminal 20 in UL (Uplink). Both the base station 10 and the terminal 20 are capable of transmitting and receiving signals by performing beamforming. In addition, both the base station 10 and the terminal 20 are capable of applying communication by MIMO (Multiple Input Multiple Output) to DL or UL. In addition, both the base station 10 and the terminal 20 may communicate via a secondary cell (SCell: Secondary Cell) and a primary cell (PCell: Primary Cell) by CA (Carrier Aggregation). Furthermore, the terminal 20 may communicate via a primary cell of the base station 10 and a primary secondary cell group cell (PSCell: Primary Secondary cell group Cell) of another base station 10 by DC (Dual Connectivity).

The terminal 20 is a communication device equipped with a wireless communication function, such as a smartphone, a mobile phone, a tablet, a wearable terminal, a communication module for M2M (Machine-to-Machine), etc. As shown in Fig. 1, the terminal 20 receives a control signal or data from the base station 10 in DL and transmits a control signal or data to the base station 10 in UL, thereby utilizing various communication services provided by the wireless communication system.

Here, in NR or LTE CA/DC, the state of a secondary cell is specified. In the active state, monitoring of control signals, data transmission and reception, and transmission and reception of control signals are performed, and further related operations, such as CSI (Channel State Information) measurement and CSI reporting, are performed. In the deactive state, monitoring of control signals, data transmission and reception, and transmission and reception of control signals are not performed, and CSI measurement, CSI reporting, etc. are not performed. In NR Release 17, an efficient activation/de-activation mechanism for secondary cells is being considered.

Fig. 2 is a diagram showing an example of control information for changing the state of a cell. The transition between the active state and the inactive state of a secondary cell is possible by notification by a MAC (Medium Access Control)-CE (Control Element) as shown in Fig. 2 or by a timer. When C _i shown in Fig. 2 is set to 1, where i is the index of a secondary cell, the secondary cell is enabled and transitions to the active state, and when C _i shown in Fig. 2 is set to 0, the secondary cell is disabled and transitions to the inactive state. When the MAC-CE is 1 octet, state transitions of secondary cells with index i from 1 to 7 are supported, and when the MAC-CE is 4 octets, state transitions of secondary cells with index i from 1 to 31 are supported.

In addition, in NR or LTE, in addition to the above-mentioned active and inactive states, a dormant state is specified as the state of a secondary cell. In the dormant state, control signal monitoring, data transmission and reception, and control signal transmission and reception are not performed, but CSI measurement is performed.

When the secondary cell state transitions from an inactive state to an active state, CSI measurement and CSI reporting must be performed after the transition, which requires time before communication can begin after the transition, resulting in a large delay. By introducing a dormant state and transitioning to the dormant state before transitioning to the active state, the delay until transitioning to the active state can be reduced.

In addition, NR introduces BWP (Bandwidth Part). By applying BWP, the UE can switch the band in which it monitors control signals, transmits and receives data, and transmits and receives control signals within the CC. Furthermore, by setting a different parameter set for each BWP, it is possible to immediately switch the parameter set. Note that it is not necessary to switch the frequency band when switching BWP. For example, two BWPs in which different values are set for parameters related to power consumption reduction can be prepared, and the parameters related to power consumption reduction can be switched by switching between these BWPs. For example, settings such as an active BWP with normal power consumption and a dormant BWP with reduced power consumption compared to normal may be made.

For example, when switching BWPs, it is expected that a narrowband BWP will be used when "there is no data to be sent or received (i.e., only monitoring of control signals is performed)" and/or "traffic is small," and a wideband BWP will be used at other times.

In addition, in NR Release 16, the MR-DC (Multi-Radio Dual Connectivity)/CA (Carrier Aggregation) enhanced work item supports a secondary cell dormancy indication function. During an active period of DRX (Discontinuous reception), a secondary cell or a group of secondary cells is notified of either a dormancy state (dormancy) or a non-dormancy state (non-dormancy) by DCI (Downlink control information). In a secondary cell that is notified of a dormancy state, the active BWP is switched to a dormant BWP, and, for example, the terminal does not monitor the PDCCH (Physical Downlink Control Channel) in the secondary cell.

Figure 3 is a diagram for explaining an example of operation related to the dormant state. As described above, in NR, a secondary cell can be transitioned to a dormant state in order to reduce power consumption.

As shown in Fig. 3, during the active period of DRX, in the primary cell or primary secondary cell group cell, scheduling is performed by DCI format 0_1 or DCI format 1_1, and each of the pre-configured secondary cell groups is notified of either "dormant state" or "non-dormant state" by a bitmap of up to 5 bits. That is, the base station 10 can notify each of up to 5 groups of secondary cells of the dormant state.

The notification may be performed by adding a bit field (0 to 5 bits) to the conventional DCI format 0_1 or DCI format 1_1 for the number of groups of secondary cells. Figure 3 shows an example of a notification to transition a group of secondary cells, "dormancy#0", consisting of SCell#1 and SCell#2, from a "dormant state" to a "non-dormant state".

Also, as shown in FIG. 3, during the active period of DRX, in the primary cell or the primary secondary cell group cells, without scheduling by DCI format 1_1, each secondary cell may be notified of either "dormant state" or "non-dormant state" by a bitmap of up to 15 bits. That is, the base station 10 may be able to notify each of up to 15 secondary cells of the dormant state.

The notification may be performed by mapping the fields "MCS (Modulation and coding scheme)" 5 bits, "NDI (New data indicator)" 1 bit, "RV (Redundancy version)" 2 bits, "HARQ process number" 4 bits, "antenna port" 4 bits to 6 bits, "DMRS sequence initialization" 0 bit or 1 bit, etc. in the conventional DCI format 1_1 to the index of the secondary cell. Figure 3 shows an example of notifying SCell #1 to transition from "non-dormant state" to "dormant state" and SCell #2 to remain in "non-dormant state".

In addition, not performing scheduling using DCI format 1_1 may mean that all bits of the field indicating resource allocation in the frequency domain are set to 0 or 1.

As shown in Figure 3, during the active DRX period, DCI formats 0_1 and 1_1 are available for transition to the dormant state. Additionally, outside the active DRX period, DCI format 2_6 is available.

As mentioned above, while a secondary cell's transition between dormant and non-dormant states is possible through Layer 1 signaling via DCI, transition between active and inactive states is not possible through Layer 1 signaling via DCI, and control by MAC-CE of Layer 2 signaling is required.

Therefore, the activation or deactivation of a secondary cell may be indicated by the DCI. For example, the activation or deactivation of each secondary cell may be explicitly indicated by a DCI field.

Figure 4 is a sequence diagram for explaining an example of operations related to cell state transitions in an embodiment of the present invention. In step S1, the base station 10 transmits DCI, which is layer 1 signaling, to the terminal 20. In the following step S2, the terminal 20 activates or deactivates the target secondary cell based on the received DCI.

Figure 5 is a diagram showing an example (1) of control information in an embodiment of the present invention. As shown in Figure 5, for example, a bitmap notifying the activation or deactivation of secondary cell #0 to secondary cell #4 may be included in the DCI field. For example, in the bitmap, "1" may indicate activation and "0" may indicate deactivation. Figure 5 is an example in which secondary cell #0 is deactivated and transitioned to an inactive state, secondary cell #1 is activated and transitioned to an active state, secondary cell #2 is activated and transitioned to an active state, secondary cell #3 is deactivated and transitioned to an inactive state, and secondary cell #4 is deactivated and transitioned to an inactive state. In addition, the terminal 20 may assume the size of the DCI field corresponding to the bitmap according to the number of secondary cells set.

In addition, the DCI notifying the activation or deactivation of the secondary cell may be notifiable only in the CC that is specified or configured. For example, the DCI notifying the activation or deactivation of the secondary cell may be notifiable only in the primary cell or the primary secondary cell group cell.

Figure 6 is a diagram showing an example of control information (2) in an embodiment of the present invention. As shown in Figure 6, for example, a bitmap notifying 0 in the case of activation or deactivation of secondary cell group #0 to secondary cell group #4 may be included in the DCI field. For example, in the bitmap, "1" may indicate activation and "0" may indicate deactivation. Figure 6 is an example in which secondary cell group #0 is deactivated and transitioned to an inactive state, secondary cell group #1 is activated and transitioned to an active state, secondary cell group #2 is activated and transitioned to an active state, secondary cell group #3 is deactivated and transitioned to an inactive state, and secondary cell group #4 is deactivated and transitioned to an inactive state. The terminal 20 may assume the size of the DCI field corresponding to the bitmap according to the number of secondary cell groups set.

In addition, the DCI notifying the activation or deactivation of the secondary cell group may be notifiable only in the CC that is specified or configured. For example, the DCI notifying the activation or deactivation of the secondary cell may be notifiable only in the primary cell or the primary secondary cell group cell.

Regarding the secondary cell group configuration, the configuration of the secondary cell group may be notified to the terminal 20 in advance by RRC signaling, etc., or the secondary cell group used in notifying the Dormant BWP may be used.

In addition, the base station 10 may use a secondary cell dormancy indication field in the DCI to explicitly notify the terminal 20 of activation/deactivation for each secondary cell or for each secondary cell group.

For example, information (e.g., 1 bit) indicating whether the secondary cell dormancy notification field is a notification for a dormant state/non-dormant state or a notification for an active state/inactive state may be notified in another field of the same DCI. The other field may be a new field or an existing field based on surplus code points or conditions, etc. The name of the "secondary cell dormancy notification field" may be another name.

As another example, the base station 10 may be able to notify the terminal 20 of one of three states, active, inactive, and dormant, by the secondary cell dormancy notification field in the DCI. The three states may be notified by changing the bits of the existing secondary cell dormancy notification field or by changing the bit interpretation.

As another example, when the terminal 20 is notified of a non-dormant state by the secondary cell dormancy notification field in the DCI, the terminal 20 may transition a secondary cell that is in an inactive state among the target secondary cells to an active state. In other words, the secondary cell dormancy notification field may be interpreted as a notification indicating activation.

As another example, when the terminal 20 is notified of the dormant state by the secondary cell dormancy notification field in the DCI, the terminal 20 may transition the secondary cells that are already in the dormant state among the target secondary cells to the inactive state. In other words, the secondary cell dormancy notification field may be interpreted as a notification indicating deactivation.

Figure 7 is a flowchart for explaining an example (1) of a cell state transition in an embodiment of the present invention. The DCI field may explicitly notify the secondary cell corresponding to the scheduling destination of the DCI of the invalidation.

In step S11, the terminal 20 receives DCI from the base station 10. In the subsequent step S12, the terminal 20 may disable the secondary cell corresponding to the scheduling destination of the DCI.

If the DCI in step S11 is same carrier scheduling, the terminal 20 may interpret this as a notification of disablement for the secondary cell that received the DCI (PDCCH).

If the DCI in step S11 is cross carrier scheduling, the terminal 20 may interpret this as a notification of invalidation of the secondary cell set as the scheduling destination of the DCI (PDCCH).

The DCI field that explicitly notifies the secondary cell corresponding to the scheduling destination of the above DCI of the invalidation may be a new field or an existing field (including a secondary cell dormancy notification field) based on a surplus code point or conditions, etc.

As described above, by explicitly notifying the secondary cell corresponding to the scheduling destination of the DCI of the invalidation, when instructing invalidation to a small number of secondary cells out of the many configured secondary cells, the invalidation can be notified with a smaller amount of data compared to notification using a bitmap corresponding to multiple secondary cells.

Figure 8 is a flowchart for explaining an example (2) of a cell state transition in an embodiment of the present invention. Based on the notification of DCI, only secondary cells that satisfy certain conditions may be enabled/disabled.

In step S21, the terminal 20 receives DCI from the base station 10. In the subsequent step S22, the terminal 20 may activate or deactivate a secondary cell that satisfies the conditions.

The DCI in step S21 may include a field indicating an instruction to disable. As a condition in step S22, for example, at the time when the terminal 20 receives the DCI in step S21, among all secondary cells or notified/specified secondary cells, the terminal 20 may disable a secondary cell whose active BWP corresponds to a dormant BWP.

The field indicating the above-mentioned invalidation instruction may be a common field (e.g., 1 bit) for all secondary cells, or may be a common field (e.g., 1 bit) for each secondary cell group. Regarding the secondary cell group configuration, the configuration of the secondary cell group may be notified to the terminal 20 in advance by RRC signaling or the like, or the secondary cell group used in notifying the dormant BWP may be used. In other words, only secondary cells that satisfy the conditions among the secondary cell group to which a common instruction is given may perform a state transition.

In addition, the field indicating the above-mentioned invalidation instruction may be a new field or an existing field (including a secondary cell dormancy notification field) based on a surplus code point or conditions, etc.

The DCI in step S21 may include a field indicating an activation instruction. As a condition in step S22, for example, at the time when the terminal 20 receives the DCI in step S21, the terminal 20 may activate a secondary cell whose active BWP corresponds to a dormant BWP among all secondary cells or notified/specified secondary cells.

In addition, the terminal 20 may be notified by the RRC setting whether the terminal 20 assumes the secondary cell activation/disable notification by layer 1 (DCI). For example, when the secondary cell activation/disable notification by layer 1 (DCI) is set based on the RRC setting, the terminal 20 may perform the layer 1 secondary cell activation/disable assuming the corresponding DCI field. Also, for example, when the secondary cell activation/disable notification by layer 1 (DCI) is set based on the RRC setting, the terminal 20 may perform the layer 1 secondary cell activation/disable assuming the corresponding DCI field, and may further perform the conventional MAC-CE-based or timer-based secondary cell activation/disable operation. When the secondary cell activation/disable notification by layer 1 (DCI) is not set or is stopped, the conventional MAC-CE-based or timer-based secondary cell activation/disable operation may be performed.

In addition, the terminal 20 may be notified by RRC configuration whether to reuse existing fields (including the secondary cell dormancy notification field) or use a new field, and may interpret the DCI based on the notification.

A UE capability indicating whether or not secondary cell activation/deactivation by layer 1 (DCI) is supported may be specified, and the UE capability may be reported from the terminal 20 to the base station 10. A terminal 20 having the UE capability may perform layer 1 activation/deactivation assuming a corresponding DCI field. A terminal 20 having the UE capability may also perform layer 1 activation/deactivation assuming a corresponding DCI field, and may further perform conventional MAC-CE-based or timer-based secondary cell activation/deactivation operations. A terminal 20 not having the UE capability may perform conventional MAC-CE-based or timer-based secondary cell activation/deactivation operations.

In addition, UE capabilities may be defined indicating whether existing fields (including the secondary cell dormancy notification field) are reusable or new fields are available, and the UE capabilities may be reported from the terminal 20 to the base station 10.

In the above-described embodiments, the notification or instruction of enable/disable may be a notification of a bit field corresponding to enable and disable respectively (e.g., 0 for disable, 1 for enable), or a bit field corresponding to a change or maintenance from the current enabled/disabled state (e.g., 0 for maintain, 1 for a transition from active to inactive or from inactive to active), or a combination thereof (e.g., 0 for maintain, 1 for enable).

In the above-described embodiment, the operations related to the notification of activation/deactivation may be combined. For example, when the terminal 20 is notified of a dormant state by the secondary cell dormancy notification field in the DCI, if the target secondary cell is in an active state, it may transition to a dormant state, and if it is already in a dormant state, it may transition to an inactive state. Also, for example, when the terminal 20 is notified of a non-dormant state by the secondary cell dormancy notification field in the DCI, it may transition the target secondary cell to an active state if it is in an inactive state, and it may also transition to an active state if it is in a dormant state.

According to the above-mentioned embodiment, the base station 10 can notify the terminal 20 of an instruction to enable/disable each secondary cell, each group of secondary cells or each individual secondary cell based on Layer 1 signaling.

In other words, in a wireless communication system, delays related to cell state transitions can be reduced.

(Device configuration)
Next, a functional configuration example of the base station 10 and the terminal 20 that execute the processes and operations described above will be described. The base station 10 and the terminal 20 include functions for implementing the above-mentioned embodiments. However, the base station 10 and the terminal 20 may each include only a part of the functions in the embodiments.

<Base Station 10>
Fig. 9 is a diagram showing an example of the functional configuration of the base station 10 in the embodiment of the present invention. As shown in Fig. 9, 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 Fig. 9 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention.

The transmitting unit 110 has a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. The transmitting unit 110 also transmits inter-network node messages to other network nodes. The receiving unit 120 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of a higher layer from the received signals. The transmitting unit 110 also has a 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 preset setting information and various setting information to be transmitted to the terminal 20. The contents of the setting information include, for example, the BWP setting of the terminal 20, the setting of a power saving signal or a power saving channel, and settings related to the activation, deactivation, or hibernation of a secondary cell.

As described in the embodiments, the control unit 140 controls the secondary cell, BWP, and power saving signal transmission. The functional unit related to signal transmission in the control unit 140 may be included in the transmitting unit 110, and the functional unit related to signal reception in the control unit 140 may be included in the receiving unit 120.

<Terminal 20>
Fig. 10 is a diagram showing an example of a functional configuration of the terminal 20 in the embodiment of the present invention. As shown in Fig. 10, 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 Fig. 10 is merely an example. The names of the functional divisions and functional units may be any as long as they can execute the operations related to the embodiment of the present invention.

The transmitter 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiver 220 wirelessly receives various signals and acquires higher layer signals from the received physical layer signals. The receiver 220 also has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL/UL/SL control signals, etc. transmitted from the base station 10. For example, the transmitter 210 transmits PSCCH (Physical Sidelink Control Channel), PSSCH (Physical Sidelink Shared Channel), PSDCH (Physical Sidelink Discovery Channel), PSBCH (Physical Sidelink Broadcast Channel), etc. to another terminal 20 as D2D communication, and the receiver 220 receives PSCCH, PSSCH, PSDCH, PSBCH, etc. from the other terminal 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 setting information that is set in advance. The contents of the setting information include, for example, the BWP setting of the terminal 20, the setting of a power-saving signal or a power-saving channel, and settings related to the activation, deactivation, or sleep of a secondary cell.

As described in the embodiments, the control unit 240 controls the secondary cell, BWP, and power saving signal transmission. The functional unit related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and the functional unit related to signal reception in the control unit 240 may be included in the receiving unit 220.

(Hardware configuration)
The block diagrams (FIGS. 9 and 10) used in the description of the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. 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 may be realized using two or more devices that are physically or logically separated and directly or indirectly connected (for example, using wires, wirelessly, etc.). The functional block may be realized by combining the one device or the multiple devices with software.

Functions include, but are not limited to, judgement, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, regard, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs the transmission function is called a transmitting unit or transmitter. In either case, as mentioned above, there are no particular limitations on the method of implementation.

For example, the base station 10, terminal 20, 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. FIG. 11 is a diagram showing an example of the hardware configuration of the base station 10 and terminal 20 in one embodiment of the present disclosure. The above-mentioned base station 10 and terminal 20 may be physically configured as a computer device including a processor 1001, a memory device 1002, an auxiliary memory device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

In the following description, the term "apparatus" may be interpreted as a circuit, device, unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the devices shown in the figure, or may be configured to exclude some of the devices.

Each function in the base station 10 and the terminal 20 is realized by loading a specific software (program) onto hardware such as the processor 1001, the memory device 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls at least one of the reading and writing of data in the memory device 1002 and the auxiliary memory device 1003.

The processor 1001, for example, operates 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 device, an arithmetic unit, a register, etc. For example, the above-mentioned control unit 140, control unit 240, etc. may be realized by the processor 1001.

The processor 1001 also reads out a program (program code), a software module, or data, etc., from at least one of the auxiliary storage device 1003 and the communication device 1004 to the storage device 1002, and executes various processes according to the program. As the program, a program that causes a computer to execute at least a part of the operations described in the above-mentioned embodiment is used. For example, the control unit 140 of the base station 10 shown in FIG. 9 may be stored in the storage device 1002 and realized by a control program that runs on the processor 1001. Also, for example, the control unit 240 of the terminal 20 shown in FIG. 10 may be stored in the storage device 1002 and realized by a control program that runs on the processor 1001. Although the above-mentioned various processes have been described as being executed by one 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 be transmitted from a network via a telecommunications line.

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

The auxiliary storage device 1003 is a computer-readable recording medium, and may be, for example, at least one of an optical disk 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 versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. The above-mentioned storage medium may be, for example, a database, a server, or other suitable medium including 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 called, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc., to realize at least one of, for example, Frequency Division Duplex (FDD) and Time Division Duplex (TDD). For example, a transmitting/receiving antenna, an amplifier unit, a transmitting/receiving unit, a transmission line interface, etc. may be realized by the communication device 1004. The transmitting/receiving unit may be implemented as a transmitting unit and a receiving unit that are physically or logically separated.

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

In addition, 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 may be configured using different buses between each device.

In addition, the base station 10 and the 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 by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

(Summary of the embodiment)
As described above, according to an embodiment of the present invention, a terminal is provided that has a receiving unit that receives control information, which is Layer 1 signaling including a field that indicates activation or deactivation of one or more secondary cells, from a base station, and a control unit that transitions the one or more secondary cells to an active state or a deactivated state for each secondary cell or for each secondary cell group based on the field.

With the above configuration, the base station 10 can notify the terminal 20 of an instruction to activate/deactivate each secondary cell, each group of secondary cells, or each individual secondary cell based on layer 1 signaling. In other words, in the wireless communication system, the delay related to the state transition of the cell can be reduced.

The receiver may receive the control information only from the primary cell or the primary secondary cell, and the controller may assume the size of the field according to the number of the one or more secondary cells. With this configuration, the terminal 20 can enable/disable each secondary cell or each group of secondary cells based on Layer 1 signaling.

The control unit may transition the one or more secondary cells to an active state or an inactive state for each secondary cell or for each secondary cell group based on the field indicating a dormant state and information indicating whether the notification is for a dormant state or a non-dormant state, or for an active state or an inactive state. With this configuration, the terminal 20 can activate/deactivate secondary cells using the field indicating a dormant state.

When a non-dormant state is notified by the field indicating a dormant state, the control unit may transition a secondary cell that is in an inactive state among the one or more secondary cells to an active state. With this configuration, the terminal 20 can use the field indicating a dormant state to enable/disable the secondary cell depending on the state of the secondary cell.

When the control unit is notified of the dormant state, the control unit may transition a secondary cell that is in a dormant state among the one or more secondary cells to an inactive state. With this configuration, the terminal 20 can use a field indicating the dormant state to enable/disable the secondary cell depending on the state of the secondary cell.

The receiver may receive from the base station a radio resource control (RRC) setting indicating whether or not the field is assumed. With this configuration, the terminal 20 can notify the base station 10 of the UE capability supporting the activation/deactivation of a secondary cell by layer 1 signaling and perform the activation/deactivation of the secondary cell by layer 1 signaling.

The terminal may further include a transmission unit that transmits to the base station a terminal capability indicating that the terminal supports enabling or disabling of a secondary cell by the control information. With this configuration, the terminal 20 can use a field indicating a dormant state to enable/disable the secondary cell depending on the state of the secondary cell.

In addition, according to an embodiment of the present invention, a communication method is provided in which a terminal executes a receiving procedure for receiving control information from a base station, the control information being Layer 1 signaling including a field indicating activation or deactivation of one or more secondary cells, and a control procedure for transitioning the one or more secondary cells to an active state or a deactivated state for each secondary cell or for each secondary cell group based on the field.

With the above configuration, the base station 10 can notify the terminal 20 of an instruction to activate/deactivate each secondary cell, each group of secondary cells, or each individual secondary cell based on layer 1 signaling. In other words, in the wireless communication system, the delay related to the state transition of the cell can be reduced.

(Supplementary description of the embodiment)
Although the embodiment of the present invention has been described above, the disclosed invention is not limited to such an embodiment, and those skilled in the art will understand various modifications, modifications, alternatives, replacements, and the like. Although the description has been given using specific numerical examples to facilitate understanding of the invention, unless otherwise specified, those numerical values are merely examples and any appropriate value may be used. The division of items in the above description is not essential to the present invention, and matters described in two or more items may be used in combination as necessary, and matters described in one item may be applied to matters described in another item (as long as there is no contradiction). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operations of multiple functional units may be physically performed by one part, or the operations of one functional unit may be physically performed by multiple parts. The order of the processing procedures described in the embodiment may be changed as long as there is no contradiction. For convenience of the processing description, the base station 10 and the terminal 20 have been described using functional block diagrams, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor possessed by the base station 10 in accordance with an embodiment of the present invention and the software operated by the processor possessed by the terminal 20 in accordance with an embodiment of the present invention may each be stored in random access memory (RAM), flash memory, read only memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

In addition, 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 may be performed by physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), higher 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. In addition, the RRC signaling may be called an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc.

Each aspect/embodiment described in this disclosure may be applied to at least one of systems utilizing LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR (new Radio), 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, UWB (Ultra-WideBand), Bluetooth (registered trademark), or other suitable systems, and next generation systems enhanced based on these. In addition, multiple systems may be applied in combination (for example, a combination of at least one of LTE and LTE-A with 5G, etc.).

The processing steps, sequences, flow charts, etc. of each aspect/embodiment described herein may be reordered unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order and are not limited to the particular order presented.

In this specification, a specific operation performed by the base station 10 may be performed by its upper node in some cases. 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 may be performed by at least one of the base station 10 and other network nodes other than the base station 10 (e.g., MME or S-GW, etc., but are not limited to these). Although the above example shows a case where there is one other network node other than the base station 10, the other network node may be a combination of multiple other network nodes (e.g., MME and S-GW).

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

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

In the present disclosure, the determination may be made based on a value represented by one bit (0 or 1), a Boolean (true or false) value, or a comparison of numerical values (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.

Additionally, software, instructions, information, etc. may be transmitted and received via a transmission medium. For example, if the 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), then these wired and/or wireless technologies are included within the definition of a transmission medium.

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.

Note that the terms described in this disclosure and the 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 the symbol may be a signal (signaling). Also, the signal may be a message. Also, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

As used in this disclosure, the terms "system" and "network" are used interchangeably.

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

The names used for the above-mentioned parameters are not limiting in any way. Moreover, the formulas etc. using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., 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 limiting in any way.

In this disclosure, terms such as "base station (BS)", "radio base station", "base station device", "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. A base station 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 provide communication services by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head). The term "cell" or "sector" refers to a part or the entire coverage area of at least one of the base station and base station subsystems that provide communication services in this coverage.

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 some other suitable terminology.

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 be a device mounted on a moving body, the moving body itself, etc. The moving body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may include a device that does not necessarily move during communication operation. 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.

In addition, 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 terminals 20 (which may be called, for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.). In this case, the 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, "side"). For example, the uplink channel, downlink channel, etc. may be read as a side channel.

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

As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. In addition, "judgment" and "decision" can include considering resolving, selecting, choosing, establishing, comparing, etc., to be a "judgment" or "decision." In other words, "judgment" and "decision" can include considering some action to be a "judgment" or "decision." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

The terms "connected" and "coupled", or any variation thereof, refer to 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". As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using at least one of one or more wires, cables, and printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and light (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

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

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."

Any reference to elements using designations such as "first," "second," etc., 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. 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 precede the second element in some way.

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

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

A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further 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.

The numerology may be a communication parameter that applies to at least one of the transmission and reception of a signal or channel. The numerology may indicate, 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 structure, a particular filtering operation performed by the transceiver in the frequency domain, a particular windowing operation performed by the transceiver in the time domain, etc.

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

A slot may include multiple minislots. Each minislot may consist of one or multiple 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 (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or 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 each be referred to by a different name.

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 minislot may be called a TTI. In other words, at least one of the subframe and the 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 the 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 terminal 20 by allocating wireless resources (such as frequency bandwidth and transmission power that can be used by each terminal 20) 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), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) in which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

In addition, when one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit of scheduling. In addition, the number of slots (minislots) constituting the minimum time unit of scheduling may be controlled.

A TTI having a time length of 1 ms may be called a normal TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, normal subframe, 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, 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 exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length less than the TTI length of a long TTI and equal to or greater than 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 the numerology, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

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

In addition, one or more RBs may 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 an index of the RB relative to a Common Reference Point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). 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".

The above-mentioned structures of radio frames, subframes, slots, minislots, and symbols 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, the symbol length, the cyclic prefix (CP) length, and other configurations can be changed in various ways.

In this disclosure, where articles have been added by translation, such as a, an, and the in English, this disclosure may include that the nouns following these articles are in the plural form.

In this disclosure, the term "A and B are different" may mean "A and B are different from each other." In addition, the term may 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."

Each aspect/embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. In addition, notification of specific information (e.g., notification that "X is the case") is not limited to being done explicitly, but may be done implicitly (e.g., not notifying the specific information).

In this disclosure, DCI is an example of control information.

Although the present disclosure has been described in detail above, it is 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 spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

10 Base station 110 Transmitter 120 Receiver 130 Setting unit 140 Control unit 20 Terminal 210 Transmitter 220 Receiver 230 Setting unit 240 Control unit 1001 Processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication device 1005 Input device 1006 Output device

Claims (7)

A receiving unit that receives control information from a base station, the control information being Layer 1 signaling including a field indicating activation or deactivation of one or more secondary cells;
A control unit that transitions the one or more secondary cells to an active state or a deactivated state for each secondary cell or for each secondary cell group based on the field ,
The control unit transitions a secondary cell that is in an inactive state among the one or more secondary cells to an active state when a non-dormant state is notified by the field that indicates a dormant state . The receiving unit receives the control information only in a primary cell or a primary secondary cell,
The terminal according to claim 1 , wherein the control unit assumes a size of the field depending on the number of the one or more secondary cells. The terminal according to claim 1, wherein the control unit transitions the one or more secondary cells to an active state or an inactive state for each secondary cell or for each secondary cell group based on the field indicating a dormant state and information indicating whether the notification is for a dormant state or a non-dormant state, or for an active state or an inactive state. The terminal according to claim 1, wherein the control unit transitions a secondary cell in a dormant state among the one or more secondary cells to an inactive state when a dormant state is notified. The terminal according to claim 1, wherein the receiver receives from the base station a radio resource control (RRC) setting indicating whether or not the field is assumed. The terminal according to claim 1, further comprising a transmission unit that transmits to the base station a terminal capability indicating support for enabling or disabling a secondary cell by the control information. A receiving procedure of receiving control information from a base station, the control information being Layer 1 signaling including a field indicating activation or deactivation of one or more secondary cells;
A control procedure for transitioning the one or more secondary cells to an active state or a deactivated state for each secondary cell or for each secondary cell group based on the field ;
and a control procedure for transitioning a secondary cell that is in an inactive state among the one or more secondary cells to an active state when a non-dormant state is notified by the field indicating a dormant state .

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