Terminal and Communication Method

Abstract

The terminal has: a communication unit that performs communication based on carrier aggregation in a primary cell, or a primary and secondary cell, and a secondary cell; and a control unit that changes an operation related to the secondary cell when a change in a communication state occurs in the primary cell, the primary and secondary cell, or the secondary cell.

Description

Technical Field

[0001] The present invention relates to a terminal and a communication method in a wireless communication system. Background Art

[0002] In a successor system of LTE (Long Term Evolution), namely NR (New Radio) (also referred to as "5G"), technologies that meet requirements such as a large-capacity system, high data transfer speed, low latency, simultaneous connection of multiple terminals, low cost, and power saving are being studied (for example, Non-Patent Document 1).

[0003] In NR, BWP (Bandwidth Part) is introduced (for example, Non-Patent Document 2). By applying BWP, a UE (User Equipment) can switch the band for monitoring control signals, data transmission / reception, and control signal transmission / reception within a CC (Component Carrier). In addition, by setting different parameter sets for each BWP, the parameter sets can be switched immediately.

[0004] Prior Art Documents

[0005] Non-Patent Documents

[0006] Non-Patent Document 1: 3GPP TS 38.300 V15.6.0 (2019-06)

[0007] Non-Patent Document 2: 3GPP TS 38.211 V15.6.0 (2019-06) Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] When a communication situation changes, such as when data is generated or the data volume increases, it may be considered to switch to a BWP suitable for the communication. However, in the case of applying CA (Carrier Aggregation), there is a situation where the switching operation cannot be performed immediately due to the state of a secondary cell (SCell), resulting in a large delay.

[0010] The present invention has been made in view of the above circumstances, and an object thereof is to perform an operation switch that follows a change in a communication situation in a wireless communication system.

[0011] Means for Solving the Problems

[0012] According to the disclosed technology, a terminal is provided, which has: a communication unit that performs communication based on carrier aggregation in a primary cell, a primary-secondary cell, or a secondary cell; and a control unit that changes an operation related to the secondary cell when a change in communication status occurs in the primary cell, the primary-secondary cell, or the secondary cell.

[0013] Advantageous Effects of the Invention

[0014] According to the disclosed technology, in a wireless communication system, it is possible to perform operation switching that follows a change in communication status. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a diagram showing a structural example of a wireless communication system in an embodiment of the present invention.

[0016] Figure 2 It is a diagram for explaining an operation related to power saving.

[0017] Figure 3 It is a flowchart for explaining an example (1) of an operation related to a secondary cell in an embodiment of the present invention.

[0018] Figure 4 It is a flowchart for explaining an example (2) of an operation related to a secondary cell in an embodiment of the present invention.

[0019] Figure 5 It is a diagram showing an example of the functional structure of a base station 10 in an embodiment of the present invention.

[0020] Figure 6 It is a diagram showing an example of the functional structure of a terminal 20 in an embodiment of the present invention.

[0021] Figure 7 It is a diagram showing an example of the hardware structure of a base station 10 or a terminal 20 in an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the embodiments described below are merely examples, and the embodiments to which the present invention is applied are not limited to the following embodiments.

[0023] When the wireless communication system according to the embodiment of the present invention operates, existing technologies can be appropriately used. However, such existing technologies are, for example, existing LTE, but are not limited to existing LTE. In addition, unless otherwise specified, the term "LTE" used in this specification has a broad meaning including LTE-Advanced and subsequent modes (e.g., NR).

[0024] In addition, in the embodiments 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 adopted. This is for ease of explanation, and signals, functions, etc. similar to them may also be referred to by other names. In addition, the above terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, etc. However, even for signals used in NR, they are not necessarily explicitly denoted as "NR-".

[0025] In addition, in the embodiments of the present invention, the duplex mode may be a TDD (Time Division Duplex) mode, an FDD (Frequency Division Duplex) mode, or may also be a mode other than these (for example, Flexible Duplex, etc.).

[0026] In addition, in the embodiments of the present invention, "configuring" radio parameters, etc. may be pre-configuring a predetermined value, or may be configuring radio parameters notified from the base station 10 or the terminal 20.

[0027] Figure 1 It is a diagram for explaining a structural example of a wireless communication system in the embodiments of the present invention. As Figure 1 shown, the wireless communication system in the embodiments of the present invention includes a base station 10 and a terminal 20. Figure 1 One base station 10 and one terminal 20 are respectively shown herein, but this is only an example, and there may be multiple of each.

[0028] The base station 10 is a communication device that provides one or more cells and communicates wirelessly with the terminal 20. The physical resources of the wireless signal are defined by the time domain and the frequency domain. The time domain can be defined by the number of OFDM (Orthogonal Frequency Division Multiplexing) symbols, and the frequency domain can 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 transmitted, for example, through NR-PBCH and is also called broadcast information. As Figure 1 shown, for example, the base station 10 transmits a control signal or data to the terminal 20 through the DL (Downlink), and receives a control signal or data from the terminal 20 through the UL (Uplink). Both the base station 10 and the terminal 20 are capable of beamforming for signal transmission and reception. In addition, both the base station 10 and the terminal 20 are capable of applying MIMO (Multiple Input Multiple Output)-based communication to the DL or UL. Additionally, both the base station 10 and the terminal 20 can communicate via a secondary cell (SCell: Secondary Cell) and a primary cell (PCell: Primary Cell) based on CA (Carrier Aggregation). Additionally, the terminal 20 can communicate via the primary cell of the base station 10 and the primary secondary cell (PSCell: Primary Secondary Cell) of another base station 10 based on DC (Dual Connectivity).

[0029] The terminal 20 is a communication device with a wireless communication function, such as a smartphone, a mobile phone, a tablet computer, a wearable terminal, a communication module for M2M (Machine-to-Machine), etc. As Figure 1 shown, the terminal 20 receives a control signal or data from the base station 10 through the DL, and transmits a control signal or data to the base station 10 through the UL, thereby utilizing various communication services provided by the wireless communication system.

[0030] Here, in the CA of NR or LTE, the states of secondary cells are defined. In the active state, monitoring of control signals, transmission and reception of data, and transmission and reception of control signals are performed. Additionally, as associated operations, for example, CSI (Channel State Information) measurement, CSI reporting, etc. are performed. In the deactive state, monitoring of control signals, transmission and reception of data, and transmission and reception of control signals are not performed, nor are CSI measurement, CSI reporting, etc.

[0031] In LTE, as the states of secondary cells, in addition to the above-mentioned active state and deactive state, a dormant state is also defined. In the dormant state, monitoring of control signals, transmission and reception of data, and transmission and reception of control signals are not performed, but CSI measurement and CSI reporting are performed.

[0032] When the state of a secondary cell migrates from the deactive state to the active state, since CSI measurement and CSI reporting are required after the migration, time is needed before communication starts after the migration, resulting in a larger delay. By introducing the dormant state, before migrating to the active state, it migrates to the dormant state, thereby reducing the delay until migrating to the active state.

[0033] Figure 2 It is a diagram for explaining operations related to power saving. In NR, the introduction of a Power saving signal / channel (hereinafter referred to as "power saving signal / channel". It can also be called a Wakeup signal) has been studied for the purpose of reducing power consumption. The base station 10 can notify the terminal 20 of information related to power saving operations through the power saving signal / channel. The power saving signal / channel can correspond to a power saving signal or a power saving channel.

[0034] For example, as Figure 2 shown, when the terminal 20 intermittently receives (CDRX: Connected mode discontinuous reception) control signals in the connected mode, by receiving the power saving signal / channel before the onduration of reception, it is determined whether to perform monitoring of control signals during the next reception period. The terminal 20 goes to sleep when the power saving signal is not detected, and when the power saving signal is detected, it receives the next reference signal, PDCCH, and PDSCH.

[0035] Research is being conducted on using the power-saving signal / channel for purposes other than the wakeup signal action equivalent to CDRX. For example, consider notifying power-saving related actions even in the normal connection mode where CDRX is not operating or during the reception period of CDRX. In the case of the normal connection mode where CDRX is not operating or during the reception period of CDRX, the power-saving signal / channel can be a physical signal different from that during the action equivalent to the wakeup signal.

[0036] In addition, in NR, BWP (Bandwidth Part) is introduced. By applying BWP, the UE can switch the band for monitoring control signals, data transmission / reception, and control signal transmission / reception within the CC. Also, by setting different parameter sets for each BWP, the parameter set can be switched immediately. In addition, when switching BWP, it is not necessary to switch the frequency band. For example, by preparing two BWPs with different values set for parameters related to power consumption reduction and switching these BWPs, the parameters related to power consumption reduction can be switched.

[0037] For example, whenever BWP is switched, the following usage is envisioned: when "there is no data transmission / reception (i.e., only control signal monitoring is performed)" and / or "the traffic volume is small", a narrowband BWP is used, and in other cases, a broadband BWP is applied.

[0038] In addition, for example, in the case of monitoring control signals or power-saving signals / channels during the reception period of CDRX, a narrowband BWP can be used. That is, BWP can be switched in association with the control of CDRX or the power-saving signal / channel.

[0039] Here, in NR, as the state of the secondary cell, a state equivalent to the sleep state is not defined, and only the active state and the inactive state are defined. Therefore, when the state of the secondary cell migrates from the inactive state to the active state, since CSI measurement and CSI reporting are required after the migration, time is required before communication starts after the migration, and the delay becomes large.

[0040] For example, when in the CDRX state and the primary cell or the primary-secondary cell is in the active state and the secondary cell is in the inactive state, and when Wakeup is notified through the power-saving signal / channel before the reception period, since it is envisioned that data is generated, the possibility of migrating the secondary cell to the active state is considered. However, since the secondary cell is in the inactive state and CSI measurement and CSI reporting are not performed, the delay becomes large.

[0041] In addition, it is assumed that, for example, when the BWP is switched, a situation occurs where data is generated or the amount of generated data increases. However, since the secondary cell is in the inactive state and CSI measurement and CSI reporting are not performed, the delay becomes large.

[0042] Accordingly, any one or more of the information shown in the following 1) to 3) can be explicitly or implicitly notified from the network to the terminal 20.

[0043] 1) Information indicating a change in the presence or absence of CSI measurement and CSI reporting in a secondary cell in the inactive state can be notified from the network to the terminal 20. That is, even for a secondary cell in the inactive state, the terminal 20 can perform CSI measurement and CSI reporting based on the notification from the network. The above operations are similar to the operations in the dormant state, but are performed in the inactive state.

[0044] 2) Information indicating a change in the presence or absence of monitoring or setting of a control signal in a secondary cell in the inactive state can be notified from the network to the terminal 20. That is, even for a secondary cell in the inactive state, the terminal 20 can perform monitoring of a control signal (PDCCH) based on the notification from the network. When monitoring a control signal in the inactive state, the associated setting may be different from the setting when monitoring a control signal in the active state. For example, in the inactive state, the control signal monitoring can be performed at a longer period than in the active state. The above-mentioned associated setting refers to, for example, the period, number of symbols, number of time slots, bandwidth, number of blind decodings, aggregation level, etc. for performing the control signal monitoring, and may also be other information notified through RRC information elements such as PDCCH-Config, PDCCH-ConfigCommon, PDCCH-ConfigSIB1, or other information specified by the specification.

[0045] 3) A change in the state of the secondary cell can be notified from the network to the terminal 20. For example, a change between the active state and the inactive state can be notified. In addition, when a dormant state is also defined in NR, a change between the active state and the dormant state and a change between the inactive state and the dormant state can be notified. The terminal 20 in the dormant state can perform only CSI measurement and CSI reporting, or can perform CSI measurement and CSI reporting and monitoring of a specified control signal. When monitoring a control signal in the dormant state, the associated setting may be different from the setting when monitoring a control signal in the active state.

[0046] Figure 3 It is a flowchart for explaining an example (1) of operations related to a secondary cell in an embodiment of the present invention. As Figure 3As shown, in step S11, the terminal 20 switches the BWP. The switching of the BWP can indicate a change in the communication situation. Then, the actions related to the secondary cell are changed (S12).

[0047] For example, the switching of the BWP in step S11 can be used as a trigger to change the presence or absence of CSI measurement and CSI reporting in the inactive secondary cell in step S12. In addition, the presence or absence or setting of the monitoring of the control signal in the inactive secondary cell can also be changed in step S12. Additionally, the state of the inactive secondary cell can also be changed in step S12. The switching of the BWP in step S11 can be a switching in the primary cell, a switching between the primary and secondary cells, or a switching in this secondary cell or another secondary cell.

[0048] Furthermore, for example, regarding the switching of the BWP in step S11, it can be notified from the network to the terminal 20 how to associate with the change in the actions of the secondary cell in step S12, or it can be specified by the specification. For example, when the normal BWP#1 and the BWP#2 for reducing power consumption (e.g., like a narrow band, some parameters are changed) are set for the terminal 20, the actions of the secondary cell can be changed as follows in a) and b).

[0049] a) When switching from BWP#2 to BWP#1, any one or more of the following a1) to a5) can be executed.

[0050] a1) The terminal 20 can start CSI measurement and CSI reporting in the inactive secondary cell.

[0051] a2) The terminal 20 can start the monitoring of the control signal in the inactive secondary cell.

[0052] a3) The terminal 20 can change the setting associated with the monitoring of the control signal in the inactive secondary cell.

[0053] a4) The terminal 20 can change the state of the inactive secondary cell to the sleep state.

[0054] a5) The terminal 20 can change the state of the inactive or sleep state secondary cell to the active state.

[0055] b) When switching from BWP#1 to BWP#2, any one or more of the following b1) to b5) can be executed.

[0056] b1) The terminal 20 can stop CSI measurement and CSI reporting in the inactive secondary cell.

[0057] b2) The terminal 20 can stop the monitoring of the control signal in the inactive secondary cell.

[0058] b3) The terminal 20 can change the settings associated with the monitoring of control signals in a secondary cell in the inactive state.

[0059] b4) The terminal 20 can change the state of an active secondary cell to the dormant state.

[0060] b5) The terminal 20 can change the state of an active or dormant secondary cell to the active state. Additionally, it can also change the presence or absence of CSI measurement and CSI reporting in a secondary cell that has been changed to the inactive state.

[0061] Additionally, in the case where multiple secondary cells are configured, the above a) or b) can be applied to a part or all of the secondary cells. Furthermore, it can be notified to the terminal 20 which secondary cell the above a) or b) is applied to, and it can also be specified by the specification. Additionally, it can be separately notified to the terminal 20 which secondary cell the above a) or b) is applied to for each BWP before or after handover, and it can also be specified by the specification. Additionally, it can be commonly notified to the terminal 20 which secondary cell the above a) or b) is applied to between the BWPs before or after handover, and it can also be specified by the specification.

[0062] Figure 4 It is a flowchart for explaining an example (2) of the operation related to a secondary cell in an embodiment of the present invention. As Figure 4 shown, in step S21, Wakeup is notified to the terminal 20 through a power saving signal / channel. The notification based on the power saving signal / channel can indicate a change in the communication status. The notification based on the power saving signal / channel can be a notification in the primary cell, the primary-secondary cell, or the secondary cell. Then, the operation related to the secondary cell is changed (S22). Step S21 and step S22 can be executed as described in the following c), d), or e).

[0063] c) In step S21, when Wakeup is notified to the terminal 20 through a power saving signal / channel before the reception period of CDRX, the change in the presence or absence of CSI measurement and CSI reporting in an inactive secondary cell, the presence or absence of monitoring of control signals in an inactive secondary cell or the change of settings, or the change of the state of the secondary cell can be explicitly notified through the power saving signal / channel. For example, it can be explicitly notified to the terminal 20 through the power saving signal / channel as described in the following c1) to c6).

[0064] c1) The presence or absence of CSI measurement and CSI reporting in an inactive secondary cell can be notified by 1 bit.

[0065] c2) The presence or absence of monitoring of control signals in an inactive secondary cell can be notified by 1 bit.

[0066] c3) It is possible to notify, by 1 bit or multiple bits, which one of the settings or the set of settings associated with the monitoring of the control signal is used.

[0067] c4) It is possible to notify, by 1 bit, an indication to change the state of a secondary cell in the inactive state to the active state or the dormant state.

[0068] c5) It is possible to notify, by 1 bit, an indication to change the state of a secondary cell in the dormant state to the active state.

[0069] c6) It is possible to notify, by 2 bits, to which state the state of the secondary cell is to be changed.

[0070] In addition, it is possible to explicitly notify the terminal 20, via a power saving signal / channel, of a combination of the information of c1) to c6) above, or a combination of other information and the information of c1 to c6) above.

[0071] d) In step S21, when Wakeup is notified to the terminal 20 via a power saving signal / channel before the reception period of CDRX, the terminal 20 can determine that it is implicitly notified of a change in the presence or absence of CSI measurement and CSI reporting in the secondary cells in the inactive state, a change in the presence or absence of monitoring of the control signal or a change in the setting in the secondary cells in the inactive state, or a change in the state of the secondary cell. For example, the terminal 20 can perform any one or more of the actions shown in d1) to d5) below.

[0072] d1) It is possible to start CSI measurement and CSI reporting in the secondary cells in the inactive state.

[0073] d2) It is possible to start monitoring of the control signal in the secondary cells in the inactive state.

[0074] d3) It is possible to change the setting or settings associated with the monitoring of the control signal in the secondary cells in the inactive state.

[0075] d4) It is possible to change the state of the secondary cells in the inactive state to the dormant state.

[0076] d5) It is possible to change the state of the secondary cells in the inactive state or the dormant state to the active state.

[0077] e) In step S21, when Wakeup is notified to the terminal 20 via a power saving signal / channel before the reception period of CDRX, the actions in the case where the terminal 20 is woken up can be notified to the terminal 20 in advance or specified by a specification. For example, any one or more of the information shown in e1) to e5) below can be notified to the terminal 20 or specified by a specification.

[0078] e1) It is possible to notify or stipulate by specification the presence or absence of CSI measurement and CSI reporting in a secondary cell in the deactivated state.

[0079] e2) It is possible to notify or stipulate by specification the presence or absence of monitoring of control signals in a secondary cell in the deactivated state.

[0080] e3) It is possible to notify or stipulate by specification which one of the settings or the set associated with the monitoring of control signals is to be used.

[0081] e4) It is possible to notify or stipulate by specification an indication to change the state of a secondary cell in the deactivated state to the active state or the dormant state.

[0082] e5) It is possible to notify or stipulate by specification an indication to change the state of a secondary cell in the dormant state to the active state.

[0083] e6) It is possible to notify or stipulate by specification to which state the state of the secondary cell is to be changed.

[0084] In addition, it is possible to notify the terminal 20 in advance or stipulate by specification a combination of the information in e1) to e6) above, or a combination of other information and the information in e1) to e6) above.

[0085] In addition, c), d) or e) above can be executed in combination.

[0086] In addition, in the case where a plurality of secondary cells are configured, c), d) or e) above can be applied to a part or all of the secondary cells. In addition, it is possible to notify the terminal 20 of which secondary cells c), d) or e) above are applied to, or it can be stipulated by specification.

[0087] In addition, in the case where Wakeup is notified to the terminal 20 by a power saving signal / channel before the reception period of CDRX and the switching of the BWP is also notified at the same time, the presence or absence of CSI measurement and CSI reporting in a secondary cell in the deactivated state can be changed in association with the switching of the BWP, the presence or absence or setting of monitoring of control signals in a secondary cell in the deactivated state can also be changed, and the state of the secondary cell can also be changed.

[0088] That is, in the case where Wakeup is notified to the terminal 20 by a power saving signal / channel before the reception period of CDRX and the switching of the BWP is also notified at the same time, similar to the operation based on the switching of the BWP in step S11 shown in Figure 3 The operation of the secondary cell can be changed as in a) or b) above.

[0089] In addition, in the case where the switching of the BWP is notified to the terminal 20 via a power saving signal / channel, the presence or absence of CSI measurement and CSI reporting in the secondary cell in the inactive state can be changed in association with the switching of the BWP. The presence or absence or setting of the monitoring of the control signal in the secondary cell in the inactive state can also be changed, and the state of the secondary cell can also be changed.

[0090] That is, in the case where the switching of the BWP is notified via a power saving signal / channel, similar to the operation based on the switching of the BWP in step S11 shown in Figure 3 above, the operation of the secondary cell can be changed as in a) or b) above.

[0091] In addition, the case where Wakeup is notified to the terminal 20 via a power saving signal / channel before the reception period of CDRX can be excluded from the above case where the switching of the BWP is notified via a power saving signal / channel, or can be included in the above case where the switching of the BWP is notified via a power saving signal / channel.

[0092] In addition, "CSI" in CSI measurement and CSI reporting can include one or more of CQI (Channel quality indicator), PMI (Precoding matrix indicator), PTI (Precoding type indicator), RI (Rank indicator), LI (Layer indicator), L1-RSRP (Reference signal received power), CRI (CSI-RS resource indicator), and SSBRI (SS / PBCH block resource indicator).

[0093] In addition, the terminal 20 can change the presence or absence of CSI measurement and CSI reporting in the secondary cell in the inactive state triggered by a notification associated with cross-slot scheduling, can also change the presence or absence or setting of the monitoring of the control signal in the secondary cell in the inactive state, and can also change the state of the secondary cell in the inactive state. The notification based on cross-slot scheduling can indicate a change in the communication situation.

[0094] The notification associated with cross-slot scheduling can be a handover in the primary cell, a handover in the primary and secondary cells, or a handover in this secondary cell or other secondary cells. Cross-slot scheduling refers to scheduling data signals in different time slots by control signals. The notification associated with cross-slot scheduling can be a notification of the handover between the same time slot scheduling and cross-slot scheduling, or a notification that the minimum K_0 value that can be set is 1 or more. The K_0 value refers to the time slot offset for scheduling data signals notified by control signals.

[0095] For the above-mentioned notification associated with cross-slot scheduling, it can be notified through BWP handover, through power-saving signals / channels, or through other control signals or signaling such as L1, MAC, or RRC.

[0096] In addition, the terminal 20 can notify the network of a flag indicating whether to apply the changes of the respective actions in the above-mentioned secondary cell. For example, this flag can be UE capability.

[0097] Through the above embodiments, the terminal 20 can reduce the delay associated with the handover of actions by switching the actions of the secondary cell according to the change of the communication situation.

[0098] That is, in a wireless communication system, it is possible to perform an action handover following the change of the communication situation.

[0099] (Device Structure)

[0100] Next, a functional structure example of the base station 10 and the terminal 20 that perform the processing actions described above will be described. The base station 10 and the terminal 20 have the functions of implementing the above-mentioned embodiments. However, the base station 10 and the terminal 20 may also each have only a part of the functions in the embodiments.

[0101] <Base Station 10>

[0102] Figure 5 is a diagram showing an example of the functional structure of the base station 10 in the embodiment of the present invention. As Figure 5 shown, the base station 10 has a transmission unit 110, a reception unit 120, a setting unit 130, and a control unit 140. Figure 5 The functional structure shown is only an example. As long as the actions related to the embodiment of the present invention can be performed, the functional division and the names of the functional units can be arbitrary.

[0103] The transmitting unit 110 includes a function of generating a signal to be transmitted to the terminal 20 side and transmitting the signal wirelessly. In addition, the transmitting unit 110 transmits inter-network node messages to other network nodes. The receiving unit 120 receives various signals transmitted from the terminal 20 and has a function of obtaining, for example, higher layer information from the received signals. In addition, the transmitting unit 110 has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, etc. to the terminal 20. In addition, the receiving unit 120 receives inter-network node messages from other network nodes.

[0104] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20. The content of the setting information is, for example, information related to the BWP setting of the terminal 20, the setting of the power saving signal or the power saving channel, the setting of the secondary cell, etc.

[0105] As described in the embodiments, the control unit 140 performs control related to the secondary cell, BWP, and power saving signal transmission. The functional units related to signal transmission in the control unit 140 may be included in the transmitting unit 110, and the functional units related to signal reception in the control unit 140 may be included in the receiving unit 120.

[0106] <Terminal 20>

[0107] Figure 6 is a diagram showing an example of the functional structure of the terminal 20 in the embodiment of the present invention. As Figure 6 shown, the terminal 20 has a transmitting unit 210, a receiving unit 220, a setting unit 230, and a control unit 240. Figure 6 The functional structure shown is only an example. As long as the actions related to the embodiments of the present invention can be executed, the functional division and the names of the functional units can be arbitrary.

[0108] The transmitting unit 210 generates a transmission signal based on transmission data and transmits the transmission signal wirelessly. The receiving unit 220 receives various signals wirelessly and obtains a higher-layer signal from the received physical layer signal. In addition, the receiving unit 220 has a function of receiving NR-PSS, NR-SSS, NR-PBCH, DL / UL / SL control signals, etc. transmitted from the base station 10. In addition, for example, the transmitting unit 210 transmits a PSCCH (Physical Sidelink Control Channel), a PSSCH (Physical Sidelink Shared Channel), a PSDCH (Physical Sidelink Discovery Channel), a PSBCH (Physical Sidelink Broadcast Channel), etc. to another terminal 20 as D2D communication, and the receiving unit 220 receives a PSCCH, a PSSCH, a PSDCH, or a PSBCH, etc. from another terminal 20.

[0109] The setting unit 230 stores various setting information received by the receiving unit 220 from the base station 10. In addition, the setting unit 230 also stores preset setting information. The content of the setting information is, for example, the BWP setting of the terminal 20, the setting of a power saving signal or a power saving channel, the setting of a secondary cell, etc.

[0110] As described in the embodiments, the control unit 240 performs control related to secondary cells, BWP, and power saving signal transmission. The functional units related to signal transmission in the control unit 240 may be included in the transmitting unit 210, and the functional units related to signal reception in the control unit 240 may be included in the receiving unit 220.

[0111] (Hardware Structure)

[0112] The block diagrams ( Figure 5 and Figure 6 ) used in the description of the above embodiments show blocks in terms of functions. These functional blocks (structural parts) are implemented by any combination of at least one of hardware and software. In addition, there is no particular limitation on the implementation method of each functional block. That is, each functional block can be implemented using a single device physically or logically combined, or two or more physically or logically separated devices can be directly or indirectly (e.g., using wired, wireless, etc.) connected and these multiple devices can be used to implement it. The functional block can also be implemented by combining software with the above single device or the above multiple devices.

[0113] Functionally, it has judgment, decision-making, determination, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, solution, selection, establishment, comparison, assumption, expectation, regarded as, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocation (allocating, mapping), assignment (assigning), etc., but is not limited to these. For example, a functional block (structural part) that enables transmission to function is called a transmitting unit or a transmitter. In short, as described above, there is no particular limitation on the implementation method.

[0114] For example, the base station 10, the terminal 20, etc. in an embodiment of the present disclosure can all function as a computer for processing the wireless communication method of the present disclosure. Figure 7 FIG. is an example showing the hardware structure of the base station 10 and the terminal 20 according to an embodiment of the present disclosure. The above-mentioned base station 10 and terminal 20 can also be respectively configured as computer devices physically 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, and a bus 1007, etc.

[0115] In addition, in the following description, the term "device" can be replaced with "circuit", "equipment (device)", "unit", etc. The hardware structure of the base station 10 and the terminal 20 can be configured to include one or more of the devices shown, or can be configured not to include some of the devices.

[0116] Each function in the base station 10 and the terminal 20 is implemented by the following method: a predetermined software (program) is read into hardware such as the processor 1001 and the storage device 1002, so that the processor 1001 performs operations and controls at least one of the communication of the communication device 1004 or the reading and writing of data in the storage device 1002 and the auxiliary storage device 1003.

[0117] The processor 1001, for example, operates the operating system to control the entire computer. The processor 1001 can also be composed of a central processing unit (CPU: Central Processing Unit) including an interface with peripheral devices, a control device, an arithmetic device, registers, etc. For example, the above-mentioned control unit 140 and control unit 240 can be implemented by a processor.

[0118] In addition, the processor 1001 reads out a program (program code), software module, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 to the storage device 1002, and performs various processes accordingly. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiments is used. For example, Figure 5 The control unit 140 of the base station 10 shown can be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. In addition, for example Figure 6 The control unit 240 of the terminal 20 shown can also be implemented by a control program stored in the storage device 1002 and operated by the processor 1001. Regarding the above-described various processes, although it has been described that the above-described various processes are executed by one processor 1001, the above-described various processes may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may also be installed by one or more chips. In addition, the program may be sent from a network via a telecommunication line.

[0119] The storage device 1002 is a computer-readable recording medium, and may be constituted by 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 referred to as a register, a cache, a main memory (main storage device), etc. The storage device 1002 can store a program (program code), a software module, etc. that can be executed in order to implement the communication method according to one embodiment of the present disclosure.

[0120] The auxiliary storage device 1003 is a computer-readable recording medium, and may be constituted by at least one of, for example, an optical disc such as a CD-ROM (Compact Disc ROM), a hard disk drive, a floppy disk, a magneto-optical disc (for example, a compact disc, a digital versatile disc, a Blu-ray (registered trademark) disc, a smart card, a flash memory (for example, a card, a stick, a key drive (Key drive)), a Floppy (registered trademark) disk, a magnetic stripe, etc. The above-described storage medium may be, for example, a database, a server, or other appropriate medium including at least one of the storage device 1002 and the auxiliary storage device 1003.

[0121] The communication device 1004 is hardware (a transceiver device) for communicating between computers via at least one of a wired network and a wireless network. For example, it can also be referred to as a network device, a network controller, a network card, a communication module, etc. The communication device 1004, for example, in order to implement at least one of frequency division duplex (FDD: Frequency Division Duplex) and time division duplex (TDD: Time Division Duplex), can also be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. For example, a transceiver antenna, an amplification unit, a transceiver unit, a transmission path interface, etc. can also be implemented by the communication device 1004. The transceiver unit can also be physically or logically separately installed by a transmission unit and a reception unit.

[0122] 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. In addition, the input device 1005 and the output device 1006 can also be integrally formed (e.g., a touch panel).

[0123] 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 can be configured using a single bus, or can be configured using different buses for each device pair.

[0124] In addition, the base station 10 and the terminal 20 can each be configured to include hardware such as a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), an FPGA (Field Programmable Gate Array), etc., and a part or all of each functional block can also be implemented by this hardware. For example, the processor 1001 can also be installed using at least one of these hardwares.

[0125] (Summary of the Embodiment)

[0126] As described above, according to an embodiment of the present invention, there is provided a terminal having: a communication unit that performs communication based on carrier aggregation in a primary cell or a primary-secondary cell and a secondary cell; and a control unit that changes an operation related to the secondary cell when a change in a communication state occurs in the primary cell, the primary-secondary cell, or the secondary cell.

[0127] With the above structure, the terminal 20 can reduce the delay of handover accompanied by actions by switching the secondary cell according to the change in the communication status. That is, in a wireless communication system, an action handover following the change in the communication status can be performed.

[0128] The change in the communication status may be a handover of a bandwidth part (BWP). With this structure, the terminal 20 can reduce the delay of handover accompanied by actions by switching the secondary cell according to the BWP handover.

[0129] The change in the action related to the secondary cell may be any one or more of the following 1) to 5):

[0130] 1) Start or stop of CSI measurement and CSI reporting in a non-active secondary cell

[0131] 2) Start or stop of monitoring of control signals in a non-active secondary cell

[0132] 3) Change of settings related to monitoring of control signals in a non-active secondary cell

[0133] 4) Changing the state of a non-active secondary cell to a dormant state

[0134] 5) Changing the state of a non-active or dormant secondary cell to an active state.

[0135] With this structure, the terminal 20 can reduce the delay of handover accompanied by actions by switching the secondary cell according to the BWP handover.

[0136] The change in the communication status may be a notification based on the start of a power saving signal. With this structure, the terminal 20 can reduce the delay of handover accompanied by actions by switching the secondary cell according to the notification based on the start of the power saving signal.

[0137] The notification based on the start of the power saving signal may include any one or more of the following 1) to 6) information;

[0138] 1) Presence or absence of CSI measurement and CSI reporting in a non-active secondary cell

[0139] 2) Presence or absence of monitoring of control signals in a non-active secondary cell

[0140] 3) Information indicating which setting or set of settings related to monitoring of control signals is used

[0141] 4) Indication to change the state of a secondary cell in the deactivated state to the active state or the dormant state

[0142] 5) Indication to change the state of a secondary cell in the dormant state to the active state

[0143] 6) Information indicating which state the state of the secondary cell is to be changed to.

[0144] With this structure, the terminal 20 can reduce the delay associated with the handover of actions by switching the actions of the secondary cell according to the notification of activation based on the power saving signal.

[0145] The change in the communication situation may be a notification of cross-slot scheduling. With this structure, the terminal 20 can reduce the delay associated with the handover of actions by switching the actions of the secondary cell according to the notification of cross-slot scheduling.

[0146] The change in the actions related to the secondary cell may be any one or more of 1) to 4) shown below;

[0147] 1) Presence or absence of CSI measurement and CSI reporting in a secondary cell in the deactivated state

[0148] 2) Presence or absence of monitoring of control signals in a secondary cell in the deactivated state

[0149] 3) Change in the setting of monitoring of control signals in a secondary cell in the deactivated state

[0150] 4) Change in the state of a secondary cell in the deactivated state.

[0151] With this structure, the terminal 20 can reduce the delay associated with the handover of actions by switching the actions of the secondary cell according to the notification of cross-slot scheduling.

[0152] Furthermore, according to an embodiment of the present invention, there is provided a communication method executed by a terminal, wherein the communication method includes the following steps: a communication step of performing communication based on carrier aggregation in a primary cell or a primary-secondary cell and a secondary cell; and a control step of changing an action related to the secondary cell when a change in the communication situation occurs in the primary cell, the primary-secondary cell, or the secondary cell.

[0153] With the above structure, the terminal 20 can reduce the delay associated with the handover of actions by switching the actions of the secondary cell according to the change in the communication situation. That is, in a wireless communication system, it is possible to perform an action handover following the change in the communication situation.

[0154] (Supplement to the embodiment)

[0155] The above has described the embodiments of the present invention. However, the disclosed invention is not limited to such embodiments, and those of ordinary skill in the art should understand various variations, modifications, substitution examples, replacement examples, etc. Specific numerical examples have been used for the purpose of facilitating the understanding of the invention, but these numerical values are only examples as long as not specifically indicated, and any appropriate arbitrary values can also be used. The distinction of items in the above description is not essential for the present invention. The matters described in two or more items can be combined as needed, or the matters described in one item can be applied to the matters described in other items (as long as there is no contradiction). The boundary of the functional units or processing units in the functional block diagram does not necessarily correspond to the boundary of physical components. The operations of multiple functional units can be physically performed by one component, or the operation of one functional unit can also be physically performed by multiple components. Regarding the processing procedures described in the embodiments, the order of processing can be swapped without contradiction. For the convenience of explaining the processing, the base station 10 and the terminal 20 are described using functional block diagrams, but such devices can also be implemented by hardware, software, or a combination thereof. The software that operates through the processor of the base station 10 according to the embodiments of the present invention and the software that operates through the processor of the terminal 20 according to the embodiments of the present invention can also be stored in a random access memory (RAM), flash memory, read-only memory (ROM), EPROM, EEPROM, register, hard disk drive (HDD), removable disk, CD-ROM, database, server, and other appropriate arbitrary storage media respectively.

[0156] In addition, the notification of information is not limited to the forms / embodiments described in the present disclosure, and other methods can also be used. For example, the notification of information can be implemented through physical layer signaling (e.g., DCI (Downlink Control Information), UCI (Uplink Control Information)), high 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 a combination thereof. In addition, the RRC signaling can be referred to as an RRC message. For example, it can also be an RRC connection setup (RRC Connection Setup) message, an RRC connection reconfiguration (RRC Connection Reconfiguration) message, etc.

[0157] Each form / embodiment described in the present disclosure can also be applied to at least one of LTE (Long Term Evolution), LTE-A (LTE-Advanced), 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 (UltraMobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), systems using other appropriate systems, and next-generation systems extended therefrom. In addition, multiple systems (for example, a combination of at least one of LTE and LTE-A and 5G, etc.) can also be combined and applied.

[0158] For the processing procedures, timings, flows, etc. of each form / embodiment described in this specification, the order can be changed without contradiction. For example, for the methods described in the present disclosure, the order of illustration indicates the elements of various steps, but is not limited to the specific order indicated.

[0159] In this specification, specific actions performed by the base station 10 are sometimes performed by its upper node according to circumstances. In a network composed of one or more network nodes having the base station 10, various actions performed for communicating with the terminal 20 can be performed by at least one of the base station 10 and other network nodes other than the base station 10 (for example, MME or S-GW, etc. are considered, but are not limited to these). In the above, the case where there is one other network node other than the base station 10 is illustrated, but the other network nodes can also be a combination of multiple other network nodes (for example, MME and S-GW).

[0160] The information or signals described in the present disclosure can be output from a higher layer (or a lower layer) to a lower layer (or a higher layer). It can also be input or output via multiple network nodes.

[0161] Information such as input or output can be stored in a specific location (e.g., memory), or can be managed using a management table. Information such as input or output can be rewritten, updated, or appended. Information such as output can also be deleted. Information such as input can also be sent to other devices.

[0162] The determination in the present disclosure can be made by a value represented by 1 bit (0 or 1), can also be made by a Boolean value (true or false), and can also be made by a numerical comparison (e.g., comparison with a predetermined value).

[0163] For software, regardless of whether it is called software, firmware, middleware, microcode, hardware description language, or by other names, it should be broadly interpreted as referring to commands, command sets, code, code segments, program code, programs, subroutines, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, processes, functions, etc.

[0164] In addition, software, commands, information, etc. can be transmitted and received via a transmission medium. For example, when software is sent from a website, server, or other remote source using at least one of wired technologies (such as coaxial cables, fiber optic cables, twisted pairs, and digital subscriber line (DSL)) and wireless technologies (such as infrared and microwave), at least one of these wired technologies and wireless technologies is included in the definition of the transmission medium.

[0165] Any one of a variety of different technologies can be used to represent the information, signals, etc. described in the present disclosure. For example, the data, commands, instructions, information, signals, bits, symbols, chips, etc. involved in the above description as a whole can be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination of these.

[0166] In addition, for the terms described in the present disclosure and the terms required to understand the present disclosure, they can be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol can be a signal (signaling). In addition, a signal can be a message. Additionally, a component carrier (CC) can be a carrier frequency, a cell, a frequency carrier, etc.

[0167] Terms such as "system" and "network" used in the present disclosure can be used interchangeably.

[0168] In addition, for the information, parameters, etc. described in this disclosure, they can be represented by absolute values, or by relative values with respect to a predetermined value, or by corresponding other information. For example, radio resources can be indicated by an index.

[0169] The names used for the above-mentioned parameters are non-restrictive at any point. Furthermore, mathematical expressions, etc. using these parameters are sometimes different from the content explicitly shown in this disclosure. Various channels (such as PUCCH, PDCCH, etc.) and information elements can be identified by appropriate names, and thus the various names assigned to these various channels and information elements are non-restrictive at any point.

[0170] In this disclosure, terms such as "base station (BS: Base Station)", "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", "component carrier", etc. can be used interchangeably. Sometimes, base stations are also referred to as macro cells, small cells, femto cells, pico cells, etc.

[0171] A base station can accommodate one or more (e.g., 3) cells. When a base station accommodates multiple cells, the overall coverage area of the base station can be divided into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (such as a small indoor base station (RRH: Remote Radio Head)). Terms such as "cell" or "sector" refer to a part or the whole of the coverage area of at least one of the base station and the base station subsystem that provides communication services within that coverage range.

[0172] In this disclosure, terms such as "mobile station (MS: Mobile Station)", "user terminal", "user equipment (UE: User Equipment)", "terminal", etc. can be used interchangeably.

[0173] For a mobile station, those skilled in the art sometimes also use the following terms to refer to it: 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 appropriate terms.

[0174] At least one of the base station and the mobile station may be referred to as a transmitting device, a receiving device, a communication device, etc. In addition, 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.), may also be a moving body that moves in an unmanned manner (e.g., a drone, a self-driving vehicle, etc.), or may also be a robot (humanoid or non-humanoid). In addition, at least one of the base station and the mobile station also includes a device that does not necessarily move during the 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.

[0175] In addition, the base station in the present disclosure may be replaced with a user terminal. For example, with respect to a structure in which the communication between the base station and the user terminal is replaced with the communication between multiple terminals 20 (e.g., it may also be referred to as D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc.), various forms / embodiments of the present disclosure can also be applied. In this case, it may be configured such that the terminal 20 has the functions of the above-described base station 10. In addition, terms such as "uplink" and "downlink" can be replaced with terms corresponding to the communication between terminals (e.g., "side"). For example, the uplink channel, the downlink channel, etc. can be replaced with the side channel.

[0176] Similarly, the user terminal in the present disclosure may be replaced with a base station. In this case, it may be configured such that the base station has the functions of the above-described user terminal.

[0177] The terms "determining" and "deciding" as used in the present disclosure sometimes also include situations involving a variety of actions. For example, "determining" and "deciding" can include cases where what has been judged, calculated, computed, processed, derived, investigated, looked up (e.g., looked up in a table, database, or other data structure), searched, or ascertained is regarded as having been "determined" or "decided". In addition, "determining" and "deciding" can include cases where what has been received (e.g., received information), transmitted (e.g., transmitted information), input, output, or accessed (e.g., accessed data in a memory) is regarded as a matter of "determining" or "deciding". Further, "determining" and "deciding" can include cases where what has been resolved, selected, chosen, established, compared, etc. is regarded as a matter of "determining" or "deciding". That is, "determining" and "deciding" can include any matter for which an arbitrary action has been "determined" or "decided". In addition, "determining (deciding)" can be replaced with "assuming", "expecting", or "considering".

[0178] The terms "connected" and "coupled" or any variations thereof are intended to represent all direct or indirect connections or couplings between two or more elements, and can include cases where there is one or more intermediate elements between the two elements that are "connected" or "coupled" to each other. The coupling or connection between elements can be a physical coupling or connection, a logical coupling or connection, or a combination thereof. For example, "connected" can be replaced with "accessed". In the context of the present disclosure, it can be considered that two elements are "connected" or "coupled" to each other using at least one of one or more electric wires, cables, and printed electrical connections, and, as some non-limiting and non-inclusive examples, using electromagnetic energy having wavelengths in the radio frequency domain, microwave region, and optical (including both visible and invisible) regions, etc.

[0179] The reference signal can be abbreviated as RS (Reference Signal) and can also be called a pilot according to the applied standard.

[0180] The description such as "according to" used in the present disclosure does not mean "only according to" unless otherwise specified. In other words, the description "according to" means both "only according to" and "at least according to".

[0181] Any reference to an element using terms such as "first", "second", etc. used in the present disclosure does not entirely limit the quantity and order of these elements. These terms are used in the present disclosure as a simple method for distinguishing between two or more elements. Therefore, the reference to the first and second elements does not mean that only two elements can be adopted here or that the first element must precede the second element in any form.

[0182] The "unit" in the above-described device structures can be replaced with a "section", "circuit", "device", etc.

[0183] When the terms "include", "including" and their variants are used in the present disclosure, these terms are inclusive in the same way as the term "comprising". Also, the term "or" used in the present disclosure does not mean exclusive or.

[0184] A radio frame can be composed of one or more frames in the time domain. In the time domain, each of the one or more frames can be called a subframe. Furthermore, a subframe can be composed of one or more time slots in the time domain. A subframe can have a fixed time length (e.g., 1 ms) independent of the numerology.

[0185] The numerology can be communication parameters applied to at least one of transmission and reception of a certain signal or channel. The numerology can represent, for example, at least one of subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering processing performed by a transceiver in the frequency domain, specific windowing processing performed by a transceiver in the time domain, etc.

[0186] A time slot can be composed of one or more symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbols, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbols, etc.) in the time domain. A time slot can be a time unit based on a parameter set.

[0187] A time slot can contain multiple mini-slots. Each mini-slot can be composed of one or more symbols in the time domain. In addition, a mini-slot can also be referred to as a sub-slot. A mini-slot can be composed of a smaller number of symbols than a time slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a mini-slot can be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a mini-slot can be called PDSCH (or PUSCH) mapping type B.

[0188] A radio frame, a sub-frame, a time slot, a mini-slot, and a symbol all represent time units when transmitting signals. A radio frame, a sub-frame, a time slot, a mini-slot, and a symbol can be respectively given corresponding other names.

[0189] For example, 1 sub-frame can be called a Transmission Time Interval (TTI), and multiple consecutive sub-frames can also be called a TTI. 1 time slot or 1 mini-slot can also be called a TTI. That is, at least one of a sub-frame and a TTI can be a sub-frame (1 ms) in the existing LTE, or a period shorter than 1 ms (e.g., 1 - 13 symbols), or a period longer than 1 ms. In addition, the unit representing a TTI can be not a sub-frame, but a time slot, a mini-slot, etc.

[0190] Here, a TTI, for example, refers to the minimum time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (bandwidth that can be used in each terminal 20, transmission power, etc.) to each terminal 20 in units of TTI. In addition, the definition of a TTI is not limited to this.

[0191] A TTI can be a transmission time unit for a data packet (transmission block), a code block, a codeword, etc. after channel coding, or a processing unit for scheduling, link adaptation, etc. In addition, when a TTI is given, the time interval (e.g., the number of symbols) for actually mapping a transmission block, a code block, a codeword, etc. can be shorter than this TTI.

[0192] In addition, when 1 time slot or 1 mini time slot is referred to as a TTI, one or more TTIs (i.e., one or more time slots or one or more mini time slots) can be the minimum time unit for scheduling. In addition, the number of time slots (mini time slots) that make up the minimum time unit of this scheduling can be controlled.

[0193] A TTI with a time length of 1 ms is also referred to as a normal TTI (TTI in LTE Rel.8 - 12), normal TTI, long TTI, normal subframe, long subframe, time slot, etc. A TTI shorter than the normal TTI can be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, mini time slot, sub - time slot, time slot, etc.

[0194] In addition, for a long TTI (e.g., normal TTI, subframe, etc.), it can be replaced by a TTI with a time length exceeding 1 ms, and for a short TTI (e.g., shortened TTI, etc.), it can be replaced by a TTI with a length less than that of the long TTI and a length of 1 ms or more.

[0195] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain. In the frequency domain, it can contain one or more consecutive subcarriers. The number of subcarriers contained in an RB can be the same regardless of the parameter set, for example, it can be 12. The number of subcarriers contained in an RB can also be determined according to the parameter set.

[0196] In addition, the time domain of an RB can contain one or more symbols, and can be the length of 1 time slot, 1 mini time slot, 1 subframe, or 1 TTI. 1 TTI, 1 subframe, etc. can be composed of one or more resource blocks respectively.

[0197] In addition, one or more RBs can be referred to as physical resource blocks (PRBs), sub - carrier groups (SCGs), resource element groups (REGs), PRB pairs, RB pairs, etc.

[0198] In addition, a resource block can be composed of one or more resource elements (REs). For example, 1 RE can be a radio resource area of 1 subcarrier and 1 symbol.

[0199] A Bandwidth Part (BWP) (which may also be referred to as a partial bandwidth, etc.) represents a subset of consecutive common resource blocks (RB) used by a certain parameter set in a certain carrier. Herein, the common RB can be determined by the index of the RB based on the common reference point of the carrier. PRBs are defined in a certain BWP and numbered within that BWP.

[0200] A BWP can include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). One or more BWPs can be set for a UE within one carrier.

[0201] At least one of the set BWPs can be active, and it can be assumed that the UE does not transmit or receive a predetermined signal / channel outside the active BWP. In addition, in the present disclosure, "cell", "carrier", etc. can be replaced by "BWP".

[0202] The structures of the above-mentioned radio frames, subframes, time slots, mini time slots, and symbols are merely illustrative. For example, the number of subframes included in a radio frame, the number of time slots per subframe or radio frame, the number of mini time slots included in a time slot, the number of symbols and RBs included in a time slot or mini time slot, the number of subcarriers included in an RB, and the number of symbols, symbol length, cyclic prefix (CP) length, etc. within a TTI can be changed in various ways.

[0203] In the present disclosure, for example, in the case where articles such as a, an, and the in English are added through translation, the present disclosure also includes the case where the nouns after these articles are in the plural form.

[0204] In the present disclosure, an expression such as "A is different from B" can mean "A and B are different from each other". In addition, this expression can also mean "A and B are respectively different from C". Expressions such as "separate" and "combine" can be interpreted in the same way as "different".

[0205] Each form / embodiment described in the present disclosure can be used alone, can be used in combination, or can be switched according to execution. In addition, the notification of predetermined information is not limited to being explicitly (for example, the notification of "is X") carried out, and can also be implicitly (for example, without the notification of the predetermined information) carried out.

[0206] In addition, in the present disclosure, the transmitting unit 210 and the receiving unit 220 are an example of a communication unit. Wakeup is an example of activation.

[0207] As described above, the present disclosure has been described in detail. However, for those skilled in the art, it should be clear that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented in the form of modifications and changes without departing from the gist and scope of the present disclosure determined by the claims. Therefore, the purpose of the description of the present disclosure is to illustrate, and it has no restrictive meaning for the present disclosure.

[0208] Reference numeral description:

[0209] 10 Base station

[0210] 110 Transmitting unit

[0211] 120 Receiving unit

[0212] 130 Setting unit

[0213] 140 Control unit

[0214] 20 Terminal

[0215] 210 Transmitting unit

[0216] 220 Receiving unit

[0217] 230 Setting unit

[0218] 240 Control unit

[0219] 1001 Processor

[0220] 1002 Storage device

[0221] 1003 Auxiliary storage device

[0222] 1004 Communication device

[0223] 1005 Input device

[0224] 1006 Output device

Claims

1. A terminal, wherein, The terminal has: a control unit that performs bandwidth part switching, i.e., BWP switching, for each of a plurality of secondary cells used for carrier aggregation; and a receiving unit that, when a plurality of BWPs are set in the terminal, receives, for each of the plurality of secondary cells, information indicating a BWP to be migrated to a dormant state or a BWP to be migrated from a dormant state to an active state among the plurality of BWPs, wherein the control unit switches the BWP respectively set for the plurality of secondary cells to a BWP to be migrated to the dormant state or a BWP to be migrated to the active state, the terminal includes a transmitting unit that performs CSI reporting when the secondary cell is in the dormant state and the BWP set for the secondary cell is a downlink BWP, i.e., a DL BWP.

2. The terminal according to claim 1, wherein the information is power saving information before a reception period of discontinuous reception, i.e., DRX, and the power saving information includes a wake-up indication.

3. A base station, wherein, The base station has: a transmitting unit that, when a plurality of bandwidth parts, i.e., BWPs, are set in a terminal, transmits, for each of a plurality of secondary cells used for carrier aggregation, to the terminal information indicating a BWP to be migrated to a dormant state or a BWP to be migrated from a dormant state to an active state among the plurality of BWPs; and a receiving unit, wherein the information causes the terminal to switch the BWP respectively set for the plurality of secondary cells to a BWP to be migrated to the dormant state or a BWP to be migrated to the active state, and the receiving unit receives a CSI report transmitted from the terminal when the secondary cell is in the dormant state and the BWP set for the secondary cell is a downlink BWP, i.e., a DL BWP.

4. A wireless communication method, wherein, The wireless communication method includes the following steps: The terminal performs bandwidth part switching, i.e., BWP switching, for each of a plurality of secondary cells used for carrier aggregation; and when a plurality of BWPs are set in the terminal, the terminal receives, for each of the plurality of secondary cells, information indicating a BWP to be migrated to a dormant state or a BWP to be migrated from a dormant state to an active state among the plurality of BWPs, wherein, in the step of performing the switching, the step of switching the BWP respectively set for the plurality of secondary cells to a BWP to be migrated to the dormant state or a BWP to be migrated to the active state is included, The wireless communication method includes the following step: performing CSI reporting when the secondary cell is in the dormant state and the BWP set for the secondary cell is a downlink BWP, i.e., a DL BWP.

5. A system having a terminal and a base station, wherein the terminal performs bandwidth part switching, i.e., BWP switching, for each of a plurality of secondary cells used for carrier aggregation, and when a plurality of BWPs are set in the terminal, the terminal receives, for each of the plurality of secondary cells, from the base station information indicating a BWP to be migrated to a dormant state or a BWP to be migrated from a dormant state to an active state among the plurality of BWPs, The terminal switches the BWPs respectively set for the plurality of secondary cells to the BWP to be migrated to the dormant state or the BWP to be migrated to the active state. When the secondary cell is in the dormant state and the BWP set for the secondary cell is a downlink BWP, i.e., a DL BWP, the terminal performs CSI reporting. The base station receives the CSI report.

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