Terminal and communication method

Abstract

This terminal includes a receiver that receives, from a base station, downlink control information (DCI) including a notification regarding the monitoring of a physical downlink control channel (PDCCH) and a controller that sets an operation of monitoring the PDCCH on the basis of the notification. The notification includes at least the number of times the PDCCH is skipped or a search space set group switching instruction.

Description

[Technical Field]

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

[0002] The 3GPP (3rd Generation Partnership Project) is currently studying a wireless communication system called 5G or NR (New Radio) (hereinafter, this wireless communication system will be referred to as "NR") in order to achieve a larger system capacity, a higher data transmission speed, and a lower latency in wireless sections. In 5G, various wireless technologies and network architectures are being studied to meet the requirements of achieving a throughput of 10 Gbps or more while keeping the latency in wireless sections to 1 ms or less (for example, Non-Patent Document 1).

[0003] In addition, NR is considering enhancements related to power saving, such as power saving related to DCI (Downlink Control Information)-based DRX (Discontinuous reception) in connected mode and reduction of PDCCH (Physical Downlink Control Channel) monitoring. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS 38.213 V16.3.0 (2020-09) [Non-patent document 2] 3GPP TS 38.331 V16.2.0 (2020-09) Summary of the Invention [Problem to be solved by the invention]

[0005] To reduce the PDCCH monitoring, skipping PDCCH monitoring has been considered, but a specific method for skipping PDCCH monitoring has not been specified.

[0006] The present invention has been made in view of the above points, and has an object to achieve power saving in a connected mode in a wireless communication system. [Means for solving the problem]

[0007] According to the disclosed technology, there is provided a terminal, a receiving unit that receives, from a base station, RRC (Radio Resource Control) signaling including a setting related to monitoring of a PDCCH (Physical Downlink Control Channel); and a control unit that sets an operation of monitoring the PDCCH based on the setting, wherein the receiving unit receives DCI (Downlink Control Information) including a notification related to monitoring of the PDCCH from the base station, and the control unit switches a search space set group based on the notification after a certain delay period has elapsed since receiving the notification, and sets a timing for returning to the search space set group from which the switching occurred, and the delay period is specified in consideration of a processing capability of the terminal. When the control unit receives DCI capable of notifying PDCCH skip in the PDCCH monitored in the search space set of the switching destination, it switches to the search space set of the switching source regardless of the set timing. A terminal is provided. [Effects of the Invention]

[0008] The disclosed technology provides a technology for saving power in a connected mode in a wireless communication system. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a wireless communication system according to an embodiment of the present invention. [Figure 2] FIG. 10 is a diagram illustrating an example (1) of skipping PDCCH monitoring according to an embodiment of the present invention. [Figure 3] FIG. 10 is a diagram illustrating an example (2) of skipping PDCCH monitoring according to an embodiment of the present invention. [Figure 4] FIG. 10 is a sequence diagram illustrating an example of skipping PDCCH monitoring according to an embodiment of the present invention. [Figure 5] A sequence diagram for explaining an example of switching search space set groups in an embodiment of the present invention. [Figure 6] 2 is a diagram illustrating an example of a functional configuration of a base station 10 according to an embodiment of the present invention. [Figure 7] FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal 20 according to the embodiment of the present invention. [Figure 8] 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. DETAILED DESCRIPTION OF THE INVENTION

[0010] 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 applied is not limited to the following embodiment.

[0011] In the operation of the wireless communication system according to the embodiment of the present invention, existing technologies are used as appropriate. However, the existing technologies are, for example, but 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.

[0012] Furthermore, in the embodiments of the present invention described below, terms used in existing LTE, 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), are used. This is for convenience of description, and similar signals, functions, etc. may be referred to by other names. Furthermore, the above-mentioned terms in NR correspond to NR-SS, NR-PSS, NR-SSS, NR-PBCH, NR-PRACH, etc. However, even signals used in NR are not necessarily designated as "NR-".

[0013] Furthermore, in the embodiments of the present invention, the duplex method may be a TDD (Time Division Duplex) method, an FDD (Frequency Division Duplex) method, or other methods (for example, Flexible Duplex, etc.).

[0014] Furthermore, in the embodiments of the present invention, when radio parameters and the like are "configured," it may mean that predetermined values ​​are pre-configured, or that radio parameters notified from the base station 10 or the terminal 20 are set.

[0015] Fig. 1 is a diagram illustrating a wireless communication system according to an embodiment of the present invention. As shown in Fig. 1, the wireless communication system according to the embodiment of the present invention includes a base station 10 and a terminal 20. Although Fig. 1 shows one base station 10 and one terminal 20, this is an example, and there may be a plurality of each.

[0016] 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 Orthogonal Frequency Division Multiplexing (OFDM) symbols, and the frequency domain may be defined by the number of subcarriers or the number of resource blocks. Furthermore, a TTI (Transmission Time Interval) in the time domain may be a slot or a subslot, or a TTI may be a subframe.

[0017] Base station 10 is capable of performing carrier aggregation, which aggregates multiple cells (multiple CCs (component carriers)) to communicate with terminal 20. In carrier aggregation, one primary cell (PCell) and one or more secondary cells (SCells) are used.

[0018] The base station 10 transmits a synchronization signal, system information, and the like to the terminal 20. The synchronization signal is, for example, NR-PSS and NR-SSS. The system information is transmitted, for example, on the NR-PBCH or PDSCH, and is also called broadcast information. As shown in FIG. 1 , the base station 10 transmits control signals or data to the terminal 20 on the DL (Downlink) and receives control signals or data from the terminal 20 on the UL (Uplink). Note that, here, what is transmitted on a control channel such as the PUCCH or PDCCH is called a control signal, and what is transmitted on a shared channel such as the PUSCH or PDSCH is called data, but these names are merely examples.

[0019] 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, or an M2M (Machine-to-Machine) communication module. As shown in Fig. 1, the terminal 20 receives control signals or data from the base station 10 via DL and transmits control signals or data to the base station 10 via UL, thereby utilizing various communication services provided by the wireless communication system. The terminal 20 may be referred to as a UE, and the base station 10 may be referred to as a gNB.

[0020] Terminal 20 can perform carrier aggregation, which aggregates multiple cells (multiple CCs) to communicate with base station 10. In carrier aggregation, one primary cell and one or more secondary cells are used. Also, a PUCCH-SCell having a PUCCH may be used.

[0021] In addition, NR is considering enhancements related to power saving, such as power saving related to DCI (Downlink Control Information)-based DRX (Discontinuous reception) in connected mode and reduction of PDCCH (Physical Downlink Control Channel) monitoring.

[0022] In addition, support for both search space set group switching and periodic PDCCH skipping is being considered, and a common DCI design capable of signaling both of these functions is being considered.

[0023] Therefore, the number of times PDCCH skipping is performed may be notified from base station 10 to terminal 20. The number of times PDCCH skipping is performed may be notified by DCI, by MAC-CE (Medium Access Control - Control Element), or by RRC (Radio Resource Control) signaling.

[0024] Fig. 2 is a diagram showing an example (1) of skipping PDCCH monitoring in an embodiment of the present invention. As shown in Fig. 2, terminal 20 may perform PDCCH monitoring every time it performs one PDCCH skip, and then perform PDCCH skip again, repeating PDCCH skipping a specified number of times. Fig. 2 shows an example in which two PDCCH skips, a two-slot PDCCH skip period, and one-slot PDCCH monitoring between PDCCH skips are set. Note that if terminal 20 receives scheduling addressed to itself in the monitored PDCCH, it may stop PDCCH skipping regardless of the specified number of PDCCH skips.

[0025] Fig. 3 is a diagram showing an example (2) of skipping PDCCH monitoring in an embodiment of the present invention, in which three PDCCH skips, a PDCCH skip period of one slot, and two slots of PDCCH monitoring between PDCCH skips are set.

[0026] The number of times PDCCH skipping, the PDCCH skipping period, and the PDCCH skipping cycle may be reported from base station 10 to terminal 20. For example, in Fig. 3, the number of times PDCCH skipping is 3, the PDCCH skipping period is 1 slot, and the PDCCH skipping cycle is 3 slots.

[0027] 4 is a sequence diagram illustrating an example of skipping PDCCH monitoring according to an embodiment of the present invention. In step S11, the terminal 20 receives from the base station 10 the number of times to perform PDCCH skipping. Furthermore, the terminal 20 may receive from the base station 10 the PDCCH skip period and the PDCCH monitoring period between PDCCH skips. In the following step S12, the base station 10 transmits a PDCCH to the terminal 20, and the terminal 20 performs PDCCH monitoring by applying the configured PDCCH skip.

[0028] Furthermore, base station 10 may notify terminal 20 that search space set group switching will be performed by DCI capable of notifying PDCCH skipping. For example, search space set group switching may be notified from base station 10 to terminal 20 by a DCI field that notifies the number of PDCCH skips. For example, when a specific value is notified in the DCI field, or when a value such as infinity is notified, terminal 20 may assume that search space set group switching has been notified. Furthermore, search space set group switching may be notified by other DCI fields.

[0029] Furthermore, the search space set group configuration, for example, the PDCCH monitoring period, etc., may be configured in advance by RRC signaling, etc. Furthermore, the search space set group configuration may be configured based on the value of the PDCCH skip period or the PDCCH monitoring period, etc., notified by DCI. The search space set group configuration may not be configured in advance by RRC signaling, but may be configured with a value notified by DCI, or the value configured in advance by RRC signaling may be overwritten with the value notified by DCI.

[0030] Furthermore, when switching of the search space set group is notified, the timing at which the search space set group to be switched to will return to the search space set group from which the search space set group to be switched to may be notified from base station 10 to terminal 20. Furthermore, it may be specified whether the default search space set group to be the return destination is notified from the search space set group to which the search space set group to be switched to will return.

[0031] The timing for returning to the search space set group from which the switch was made or the default search space set group may be the timing shown in 1)-5) below.

[0032] 1) After X slot or X symbol 2) After Xms 3) After X PDCCH monitoring 4) After skipping X PDCCHs 5) After X PDCCH monitoring periods

[0033] Furthermore, when terminal 20 receives scheduling addressed to itself in the monitored PDCCH, it may switch to the search space set group of the switching source or the default search space set group regardless of the above-mentioned specified timing.

[0034] When search space set group switching is performed, the magnitude of the delay required for search space set group switching may be specified differently depending on the degree of difference in parameters, etc., set between search space set groups before and after the switching (for example, the type and / or number of parameters with different values, the amount of difference between the values ​​of parameters with different values, etc.). For example, if only the PDCCH monitoring period is a different parameter between search space set groups before and after the search space set group switching and the other parameters are the same, the delay required for search space set group switching may be shortened or there may be no delay.

[0035] Furthermore, the types of parameters for which different parameter values ​​can be set between search space set groups configured in advance by RRC signaling or the like may be limited. By limiting the types of parameters for which different parameter values ​​can be set, it is possible to specify a reduced delay. For example, between search space set groups before and after search space set group switching, only the PDCCH monitoring period may be set to a different parameter value, while other parameters may not be set to different parameter values. When only the PDCCH monitoring period is set to a different parameter value between the search space set groups, while other parameters may not be set to different parameter values, only the PDCCH monitoring period may be set in one search space set group, and the other parameters may be set to values ​​of the other search space set group. The other search space set group may be specified.

[0036] Furthermore, the magnitude of the difference between parameters for which different parameter values ​​are set between search space set groups that are set in advance by RRC signaling, etc. may be limited. By limiting the magnitude of the difference between different parameter values, it becomes possible to specify a reduced delay.

[0037] The above-described search space set group switching reduces the required delay, so that search space set group switching can be performed with a delay as short as that when only PDCCH skip is notified.

[0038] When PDCCH skipping or search space set group switching is notified by DCI, a delay may be specified from the time of notification until PDCCH skipping or search space set group switching is executed, taking into consideration the processing time of terminal 20, or no delay may be specified. Regardless of the presence or absence of the delay, the reference point in time for applying PDCCH skipping or search space set group switching may be the notification timing of the DCI, or may be the transmission timing of an ACK for the DCI.

[0039] 5 is a sequence diagram illustrating an example of switching search space set groups in an embodiment of the present invention. In step S21, base station 10 transmits a search space set group switching request to terminal 20. In the following step S22, base station 10 transmits a PDCCH to terminal 20, and terminal 20 performs PDCCH monitoring by applying the switched search space set group.

[0040] According to the above-described embodiment, the terminal 20 can dynamically perform PDCCH skipping based on signaling from the base station 10. Furthermore, the terminal 20 can dynamically perform search space set group switching based on signaling from the base station 10.

[0041] That is, in the wireless communication system, power saving can be achieved in the connected mode.

[0042] (Device configuration) Next, a description will be given of an example of the functional configuration of the base station 10 and the terminal 20 that execute the processes and operations described above. The base station 10 and the terminal 20 include functions for executing the above-described embodiments. However, the base station 10 and the terminal 20 may each include only one of the functions of the embodiments.

[0043] <Base station 10> Fig. 6 is a diagram showing an example of the functional configuration of the base station 10. As shown in Fig. 6, 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. 6 is merely an example. The names of the functional divisions and functional units may be any as long as they can perform the operations related to the embodiment of the present invention. The transmitting unit 110 and the receiving unit 120 may be called a communication unit.

[0044] The transmitter 110 has a function of generating a signal to be transmitted to the terminal 20 and transmitting the signal wirelessly. The receiver 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 signal. The transmitter 110 also has a function of transmitting NR-PSS, NR-SSS, NR-PBCH, DL / UL control signals, DL data, etc. to the terminal 20. The transmitter 110 also transmits the setting information, etc., described in the embodiments.

[0045] The setting unit 130 stores preset setting information and various setting information to be transmitted to the terminal 20 in a storage device, and reads out the information from the storage device as needed. The control unit 140 performs, for example, resource allocation and overall control of the base station 10. Note that 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. Furthermore, the transmitting unit 110 and the receiving unit 120 may be called a transmitter and a receiver, respectively.

[0046] <Terminal 20> Fig. 7 is a diagram showing an example of the functional configuration of the terminal 20. As shown in Fig. 7, 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. 7 is merely an example. The names of the functional divisions and functional units may be any as long as they can perform the operations related to the embodiment of the present invention. The transmitting unit 210 and the receiving unit 220 may be called a communication unit.

[0047] The transmitter 210 creates a transmission signal from the transmission data and transmits the transmission signal wirelessly. The receiver 220 receives various signals wirelessly and acquires higher layer signals from the received physical layer signals. The transmitter 210 also transmits HARQ-ACK, and the receiver 220 receives the setting information and the like described in the embodiments.

[0048] The setting unit 230 stores various setting information received from the base station 10 by the receiving unit 220 in a storage device, and reads it out from the storage device as needed. The setting unit 230 also stores setting information that is set in advance. The control unit 240 performs overall control of the terminal 20. Note that 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. Note that the transmitting unit 210 and the receiving unit 220 may be called a transmitter and a receiver, respectively.

[0049] (Hardware configuration) The block diagrams (FIGS. 6 and 7) used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are connected directly or indirectly (for example, by wire, wirelessly, etc.) and these multiple devices. The functional block may be realized by combining the single device or the multiple devices with software.

[0050] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocation, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0051] For example, the base station 10, the terminal 20, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 8 is a diagram illustrating an example of the hardware configuration of the base station 10 and the terminal 20 according to an embodiment of the present disclosure. The base station 10 and the terminal 20 described above may be physically configured as a computer device including a processor 1001, a storage device 1002, an auxiliary storage device 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0052] In the following description, the term "apparatus" can be read as a circuit, a device, a unit, etc. The hardware configuration of the base station 10 and the terminal 20 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0053] Each function in the base station 10 and the terminal 20 is realized by loading predetermined software (programs) 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 reading and writing data in the memory device 1002 and the auxiliary memory device 1003.

[0054] The processor 1001 controls the entire computer by running, for example, an operating system. 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.

[0055] Furthermore, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the auxiliary storage device 1003 and the communication device 1004 into the storage device 1002, and executes various processes in accordance with the programs. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the control unit 140 of the base station 10 shown in FIG. 6 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. Furthermore, for example, the control unit 240 of the terminal 20 shown in FIG. 7 may be implemented by a control program stored in the storage device 1002 and running on the processor 1001. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.

[0056] The storage device 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), 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 an embodiment of the present disclosure.

[0057] The secondary 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 disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy 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 secondary storage device 1003.

[0058] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. 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 frequency division duplex (FDD) and time division duplex (TDD). For example, a transmission / reception antenna, an amplifier unit, a transmission / reception unit, a transmission path interface, etc. may be realized by the communication device 1004. The transmission / reception unit may be implemented as a transmission unit and a reception unit that are physically or logically separated.

[0059] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, 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 device (for example, a touch panel).

[0060] Furthermore, each device such as the processor 1001 and the storage device 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0061] Furthermore, base station 10 and 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, processor 1001 may be implemented using at least one of these pieces of hardware.

[0062] (Summary of the embodiment) As described above, according to an embodiment of the present invention, there is provided a terminal having a receiving unit that receives DCI (Downlink Control Information) from a base station, the DCI including a notification related to monitoring of a PDCCH (Physical Downlink Control Channel), and a control unit that sets an operation for monitoring the PDCCH based on the notification, wherein the notification includes at least the number of times to skip the PDCCH or a search space set group switching instruction.

[0063] With the above configuration, terminal 20 can dynamically execute PDCCH skipping based on signaling from base station 10. Furthermore, terminal 20 can dynamically execute search space set group switching based on signaling from base station 10. That is, in a wireless communication system, power saving in connected mode can be achieved.

[0064] When the notification includes the number of times to skip the PDCCH, the notification may further include a period for skipping the PDCCH and a period for monitoring the PDCCH between the period for skipping the PDCCH and the period for skipping the next PDCCH. With this configuration, the terminal 20 can perform PDCCH skipping based on signaling from the base station 10.

[0065] When the notification includes a search space set group switching instruction, the instruction may be notified by setting a specific value in a field including the number of times to skip PDCCH. With this configuration, terminal 20 can perform search space set group switching based on signaling from base station 10.

[0066] When the notification includes a search space set group switching instruction, the notification may further include timing for returning from the search space set group to the search space set group from which the search space set group is switched or to the default search space set group from which the search space set group is switched. With this configuration, after performing search space set group switching based on signaling from base station 10, terminal 20 can return to the search space set group from which the search space set group is switched or the default search space set group as necessary.

[0067] When the notification includes a search space set group switching instruction and, further, only the PDCCH monitoring period is different among the parameters set before and after the search space set group switching, the control unit may shorten and estimate the delay required for the search space set group switching. With this configuration, terminal 20 can execute search space set group switching based on signaling from base station 10, assuming the shortened delay.

[0068] Furthermore, according to an embodiment of the present invention, a communication method is provided in which a terminal executes a reception procedure for receiving, from a base station, DCI (Downlink Control Information) including a notification related to monitoring of a PDCCH (Physical Downlink Control Channel), and a control procedure for setting an operation for monitoring the PDCCH based on the notification, and the notification includes at least the number of times to skip the PDCCH or a search space set group switching instruction.

[0069] With the above configuration, terminal 20 can dynamically execute PDCCH skipping based on signaling from base station 10. Furthermore, terminal 20 can dynamically execute search space set group switching based on signaling from base station 10. That is, in a wireless communication system, power saving in connected mode can be achieved.

[0070] (Supplementary explanation of the embodiment) Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various modifications, alterations, alternatives, and substitutions. While specific numerical examples have been used to facilitate understanding of the invention, unless otherwise specified, these numerical values ​​are merely examples, and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention; two or more items may be combined as needed, and items described in one item may apply to items described in another item (unless inconsistent). The boundaries between functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries between physical components. The operations of multiple functional units may be performed by a single physical component, or the operations of a single functional unit may be performed by multiple physical components. The order of the processing steps described in the embodiments may be reversed as long as there is no contradiction. For convenience of processing description, the base station 10 and terminal 20 have been described using functional block diagrams. However, such devices may be implemented using hardware, software, or a combination thereof. The software operated by the processor of the base station 10 in accordance with an embodiment of the present invention and the software operated by the processor of 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, registers, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

[0071] Furthermore, 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., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB)), other signals, or a combination thereof. Furthermore, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0072] Each aspect / embodiment described in the present disclosure may be applied to at least one of systems using 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 appropriate systems, and next-generation systems extended based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G, etc.) may also be applied.

[0073] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described herein may be changed unless it is consistent. 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.

[0074] In this specification, a specific operation that is described as being performed by the base station 10 may also be performed by its upper node in some cases. In a network consisting of one or more network nodes having the 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 another network node other than the base station 10 (such as, but not limited to, an MME or an S-GW). Although the above example illustrates 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 (such as an MME and an S-GW).

[0075] The information, signals, etc. described in the present disclosure may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), or may be input / output via multiple network nodes.

[0076] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be sent to another device.

[0077] In the present disclosure, the determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0078] 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.

[0079] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0080] 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.

[0081] Note that terms explained in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Furthermore, a signal may be a message. Furthermore, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.

[0082] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0083] Furthermore, the information, parameters, etc. described in the present 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, a radio resource may be indicated by an index.

[0084] The names used for the above-described parameters are not intended to be limiting in any way. Furthermore, the mathematical expressions 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 intended to be limiting in any way.

[0085] In this disclosure, terms such as "base station (BS)," "radio base station," "base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0086] A base station can accommodate one or more (e.g., three) 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 be provided with communication service 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 ​​a base station and / or base station subsystem that provides communication service within this coverage.

[0087] In this disclosure, the terms "Mobile Station (MS)," "user terminal," "User Equipment (UE)," "terminal," etc. may be used interchangeably.

[0088] 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.

[0089] 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 mobile body, or the mobile body itself. The mobile body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned mobile body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0090] Furthermore, a base station in the present disclosure may be read as a user terminal. For example, the aspects / embodiments 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 a plurality of terminals 20 (which may be called, for example, D2D (Device-to-Device) or V2X (Vehicle-to-Everything)). In this case, the terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, terms such as an uplink channel and a downlink channel may be read as a side channel.

[0091] Similarly, the user terminal in the present disclosure may be read as a base station, in which case the base station may be configured to have the functions of the user terminal described above.

[0092] 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. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0093] The terms "connected," "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 one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0094] The reference signal may be abbreviated as RS (Reference Signal) or may be called a pilot depending on the applicable standard.

[0095] 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."

[0096] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0097] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0098] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0099] 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.

[0100] Numerology may be communication parameters that apply to at least one of transmission and reception of a signal or channel, such as subcarrier spacing (SCS), bandwidth, symbol length, cyclic prefix length, transmission time interval (TTI), number of symbols per TTI, radio frame structure, specific filtering operations performed by the transceiver in the frequency domain, and specific windowing operations performed by the transceiver in the time domain.

[0101] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol or a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol) in the time domain. A slot may be a time unit based on numerology.

[0102] 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.

[0103] The radio frame, subframe, slot, minislot, and symbol all represent time units for transmitting signals, and may be referred to by other names corresponding to the radio frame, subframe, slot, minislot, and symbol.

[0104] 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. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (for example, 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.

[0105] Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate wireless resources (such as frequency bandwidth and transmission power that can be used by each terminal 20) to each terminal 20 in TTI units. Note that the definition of TTI is not limited to this.

[0106] The TTI may be a transmission time unit for a channel-encoded 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) to which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

[0107] 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 for scheduling. Also, the number of slots (minislots) constituting the minimum time unit for scheduling may be controlled.

[0108] A TTI having a time length of 1 ms may be called a regular TTI (TTI in LTE Rel. 8-12), normal TTI, long TTI, regular subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a regular TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

[0109] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0110] A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, for example, 12. The number of subcarriers included in an RB may also be determined based on numerology.

[0111] The time domain of an RB may include one or more symbols and may have a length of one slot, one minislot, one subframe, or one TTI. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

[0112] Note that one or more RBs may also be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0113] Furthermore, a resource block may 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.

[0114] A Bandwidth Part (BWP) (which may also be referred to as a fractional bandwidth) may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by their index relative to a common reference point of the carrier. PRBs may be defined in a given BWP and numbered within that BWP.

[0115] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be set for the terminal 20 within one carrier.

[0116] At least one of the configured BWPs may be active, and the terminal 20 may not expect to transmit or receive a predetermined signal / channel outside the active BWP. Note that the terms "cell," "carrier," and the like in this disclosure may be read as "BWP."

[0117] The above-described structures of radio frames, subframes, slots, minislots, symbols, etc. 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, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0118] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0119] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0120] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0121] 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. [Explanation of symbols]

[0122] 10 base station 110 Transmitter 120 Receiver 130 Setting section 140 Control Unit 20 terminals 210 Transmitter 220 Receiving unit 230 Setting Section 240 Control Unit 1001 processor 1002 Storage device 1003 Auxiliary storage device 1004 Communication equipment 1005 Input Device 1006 Output Device

Claims

1. A terminal, A receiver that receives RRC (Radio Resource Control) signaling from a base station, the RRC signaling including settings related to monitoring of a PDCCH (Physical Downlink Control Channel); A control unit that sets an operation of monitoring a PDCCH based on the setting; and The receiving unit receives, from the base station, DCI (Downlink Control Information) including a notification related to monitoring of a PDCCH, The control unit switches the search space set group based on the notification after a certain delay period has elapsed since receiving the notification, and sets a timing to return to the search space set group from which the switching originated; The delay period is determined taking into consideration the processing capability of the terminal; When the control unit receives DCI capable of notifying PDCCH skip in the PDCCH monitored in the search space set of the switching destination, the control unit switches to the search space set of the switching source regardless of the set timing. Terminal.

2. The control unit skips the PDCCH for a certain period based on the DCI notifying the PDCCH skip. The terminal of claim 1.

3. A receiving procedure for receiving RRC (Radio Resource Control) signaling including settings related to monitoring of a PDCCH (Physical Downlink Control Channel) from a base station; A control procedure for configuring an operation of monitoring a PDCCH based on the configuration; The terminal executes The terminal receives, from the base station, DCI (Downlink Control Information) including a notification related to monitoring of a PDCCH; The terminal switches the search space set group based on the notification after a certain delay period has elapsed since receiving the notification, and sets a timing for returning to the search space set group from which the terminal was switched; The delay period is determined taking into consideration the processing capability of the terminal; When DCI capable of notifying PDCCH skip is received in the PDCCH monitored in the search space set of the switching destination, switching to the search space set of the switching source regardless of the set timing. Communication method.

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