Terminal, base station, and wireless communication system

Abstract

This terminal includes a reception unit and a control unit. The reception unit receives, from a base station, a first signal including first information about a resource on which a second signal is transmitted and second information about a resource on which a third signal is transmitted. When the reception unit receives the second signal via the resource according to the first information about the resource on which the second signal is transmitted, which is included in the first signal, the control unit executes, from a first time, adaptive control to adjust the second resource on which the third signal is transmitted.

Description

Terminal, base station, and wireless communication system

[0001] The present invention relates to a terminal, a base station, and a wireless communication system.

[0002] In today's networks, traffic from mobile devices (smartphones and feature phones) accounts for the majority of network resources, and traffic from mobile devices is expected to continue to grow.

[0003] In addition to traffic used by mobile terminals, for example, IoT (Internet of Things) services (for example, monitoring systems for transportation systems, smart meters, devices, etc.) are being deployed. Therefore, networks are required to support services with diverse requirements. In order to support such diverse services, for example, in communication standards for fifth-generation mobile communications (5G or NR (New Radio)) (for example, Non-Patent Documents 1 to 14), standards are being formulated assuming support for many use cases classified as eMBB (Enhanced Mobile Broadband), Massive MTC (Machine Type Communications), and URLLC (Ultra-Reliable and Low Latency Communications).

[0004] Currently, 3GPP (3rd Generation Partnership Project (registered trademark)) is studying common signal / channel adaptation technology as a technology for reducing network power consumption (Non-Patent Document 15). The common signal / channel may be, for example, a synchronization signal block (SSB: synchronization signal block), a physical broadcast channel (PBCH: physical broadcast channel), a primary synchronization signal (PSS: primary synchronization signal), a secondary synchronization signal (SSS: secondary synchronization signal), an access channel (PRACH: physical random access channel), a physical downlink control channel (PDCCH: physical downlink control channel) for regulating paging messages, and a physical downlink shared channel (PDSCH: physical downlink shared channel) for transmitting paging messages. Common signal / channel adaptation is a technique that allows for the adjustment of, for example, the transmission and reception cycles of common signals and channels, and the transmission and reception resources of common signals and channels (Non-Patent Document 14).

[0005] 3GPP TS 37.324 V18.0.03GPP TS 37.340 V18.2.03GPP TS 38.201 V18.0.03GPP TS 38.202 V18.3.03GPP TS 38.211 V18.3.03GPP TS 38.212 V18.3.03GPP TS 38.213 V18.3.03GPP TS 38.214 V18.3.03GPP TS 38.215 V18.3.03GPP TS 38.300 V18.2.03GPP TS 38.321 V18.2.03GPP TS 38.322 V18.1.03GPP TS 38.323 V18.2.03GPP TS 38.331 V18.2.0RP-240169

[0006] Incidentally, the adjustment of the transmission and reception cycle of the common signal / channel and the transmission and reception resources of the common signal / channel can be performed, for example, by an SI (System Information) change. However, when performing the SI change, the terminal executes an SI acquisition process after a predetermined time has elapsed since receiving a signal instructing the SI change. For example, the terminal executes the SI acquisition process after the start time of the next modification period. Then, after the SI acquisition process, the information on the transmission and reception cycle of the common signal / channel and the transmission and reception resources can be updated, thereby adjusting the transmission and reception cycle of the common signal / channel and the transmission and reception resources.

[0007] Since an earlier timing for adapting the common signal / channel can be expected to reduce the power consumption of the base station, it is preferable to shorten the time until adapting the common signal / channel. However, when the transmission / reception period and transmission / reception resources of the common signal / channel are adjusted by the SI acquisition process after receiving the signal instructing the SI change described above, it takes a long time until the adjustment is completed. For example, if the signal instructing the SI change is received immediately after the start of correction period N, it takes a long time to wait until the start of correction period N+1 and then acquire the system information for correction period N+1.

[0008] Therefore, alternative methods for common signal / channel adaptation are required.

[0009] The disclosed technique has been made in view of the above, and provides a method for a base station and a terminal to perform common signal / channel adaptation.

[0010] In one aspect, a terminal is provided that has: a receiving unit that receives a first signal including first information regarding a first resource on which a second signal is transmitted and second information regarding a second resource on which a third signal is transmitted; and a control unit that, when the second signal is received via the first resource according to the first information, performs adaptive control from a first time to adjust the second resource on which the third signal is transmitted.

[0011] According to the above aspects, the base station and the terminal can perform common signal / channel adaptation.

[0012] FIG. 1 is a diagram showing an example of a wireless communication system according to a first embodiment. FIG. 2 is a diagram showing an example of a functional configuration block diagram of a base station in the wireless communication system according to the first embodiment. FIG. 3 is a diagram showing an example of a functional configuration block diagram of a terminal in the wireless communication system according to the first embodiment. FIG. 4 is a diagram showing an example of a sequence of the wireless communication system according to the first embodiment. FIG. 5 is a diagram showing an example of a sequence of the wireless communication system according to the first embodiment. FIG. 6 is a diagram showing an example of a format of information included in a second signal. FIG. 7 is a diagram showing an example of a start timing of adaptation of a common signal / channel. FIG. 8 is a diagram showing an example of a start timing of adaptation of a common signal / channel. FIG. 9 is a diagram showing an example of a start timing of adaptation of a common signal / channel. FIG. 10 is a diagram showing an example of a hardware configuration of a base station. FIG. 11 is a diagram showing an example of a hardware configuration of a terminal.

[0013] The present embodiment will be described in detail below with reference to the drawings. The problems and examples in this specification are merely examples and do not limit the scope of the rights of the present application. In particular, even if the expressions used are different, the technology of the present application can be applied as long as they are technically equivalent, and do not limit the scope of the rights. Furthermore, each embodiment can be combined as appropriate within the scope of not causing any contradiction in the processing content.

[0014] Furthermore, the terms used and technical contents described in this specification may be those described in specifications and contributions as standards related to communications, such as 3GPP, as appropriate. Examples of such specifications include those described in Non-Patent Documents 1 to 14.

[0015] Hereinafter, embodiments of a base station, a terminal, and a wireless communication system disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the disclosed technology is not limited to the following embodiments.

[0016] [Problem] Before describing each embodiment, the problem in the prior art will be described. Please note that this problem was newly discovered by the inventors as a result of careful consideration of the prior art, and was not previously known.

[0017] When common signal / channel adaptation is performed, it must be performed at the same time by the terminal and the base station. If the timing is off, the terminal may not be able to receive signals from the base station, or the terminal may transmit signals to the base station at a timing other than the designated timing.

[0018] For example, if SSB adaptation is not performed at the same time at the base station and the terminal as a common signal / channel adaptation, the terminal will monitor the SSB at the conventional period, even if the period of the SSB transmitted from the base station to the terminal is extended.

[0019] Furthermore, for example, when PRACH adaptation is not performed at the same timing in the base station and the terminal as adaptation of a common signal / channel, for example, the PRACH resource for transmission by the terminal may differ from the resource set by the base station, which occurs because the PRACH adaptation causes the PRACH resource to use the resource before and after adjustment in the time domain.

[0020] Furthermore, for example, if paging adaptation as a common signal / channel adaptation is not performed at the same timing at the base station and the terminal, for example, the terminal may not be able to receive the paging signal (it may not monitor at the timing of receiving the paging signal).

[0021] For the above reasons, it is desirable to synchronize the start timing of common signal / channel adaptation between the terminal and the base station.

[0022] On the other hand, if common signal / channel adaptation is performed using SI acquisition processing from a predetermined time after receiving a signal instructing an SI (System Information) change, the start timing of common signal / channel adaptation can be aligned, but it takes time to start common signal / channel adaptation.

[0023] To summarize the above, for example, in order to reduce the power consumption of a base station, it is preferable to start common signal / channel adaptation earlier. On the other hand, it is necessary to synchronize the start timing of common signal / channel adaptation between a terminal and a base station. Therefore, a method is desired that can synchronize the start timing of common signal / channel adaptation between a terminal and a base station, and perform common signal / channel adaptation earlier than when the SI acquisition process is used from a predetermined time after receiving a signal instructing an SI change. In other words, a method is desired that can synchronize the implementation timing of common signal / channel adaptation between a terminal and a base station, while shortening the time from when the base station determines to perform common signal / channel adaptation to when the common signal / channel adaptation is performed. As mentioned above, this problem was newly discovered by the inventors as a result of careful consideration of conventional technology, and was not previously known. Hereinafter, each embodiment of the present application for solving this problem will be described in order. First Embodiment

[0024] FIG. 1 is a diagram showing an example of a wireless communication system 1 according to the first embodiment. The wireless communication system 1 includes a base station 100 and terminals 200A, 200B, and 200C. The base station 100 forms a cell C10. The terminals 200A, 200B, and 200C are present in the cell C10. When there is no need to distinguish between the terminals 200A, 200B, and 200C, they will be simply referred to as terminal 200. The RRC state of the terminal 200 is, for example, RRC (Radio Resource Control) connected, RRC inactive, or RRC idle.

[0025] The base station 100 may be, for example, a small wireless base station such as a macro wireless base station or a pico wireless base station (including a micro wireless base station, a femto wireless base station, etc.), or may be a wireless base station of various scales, and may be referred to as a wireless communication device, a communication device, a transmitting device, etc. The terminal 200 may be, for example, a wireless terminal such as various devices having a wireless communication function, such as a mobile phone, a smartphone, a PDA (Personal Digital Assistant), a personal computer, a vehicle, an airplane, a drone, or a device (sensor device, etc.) mounted on a robot, AV equipment, home appliances, office equipment, vending machines, other household equipment, industrial equipment, etc., and may be referred to as a wireless communication device, a communication device, a receiving device, a mobile station, etc.

[0026] The base station 100 is connected to a network device (a higher-level device or another base station) not shown in the figure via a wired connection. Note that the base station 100 may be connected to the network device wirelessly instead of via a wired connection.

[0027] The base station 100 may have a wireless communication function with the terminal 200 and a digital signal processing and control function separated into separate devices. In this case, the device having the wireless communication function may be called an RRH (Remote Radio Head), and the device having the digital signal processing and control function may be called a BBU (Base Band Unit). The RRHs may be installed extending from the BBU, and they may be connected by a wired connection such as optical fiber. Alternatively, they may be connected wirelessly. Instead of the aforementioned RRH and BBU, the base station 100 may be separated into, for example, a Central Unit (CU), a Distributed Unit (DU), and a Radio Unit (RU). The DU may include, for example, a MAC (Media Access Control) layer function. The DU may also include, for example, a function of an RLC (Radio Link Control) layer. The RU includes at least an RF wireless circuit. The DU and RU may also be integrated into one unit.

[0028] On the other hand, the terminal 200 communicates with the base station 100 via wireless communication.

[0029] Next, the base station 100 will be described. Fig. 2 is a diagram showing an example of a functional configuration block diagram of the base station 100. The base station 100 has a wireless communication unit 110, a control unit 120, a storage unit 130, and a communication unit 140.

[0030] The wireless communication unit 110 is composed of a transmitting unit 111 and a receiving unit 112, and performs wireless communication with the terminal 200. Specifically, the transmitting unit 111 transmits to the terminal 200 downlink signals such as a synchronization signal, an SS / PBCH, a paging signal, a random access procedure signal, an RRC layer signal, a downlink data signal, and a downlink control signal.

[0031] The receiving unit 112 can receive uplink signals transmitted from the terminal 200, such as signals of a random access procedure, signals of an RRC layer, uplink data signals, and uplink control signals.

[0032] The control unit 120 controls the base station 100. Specifically, the control unit 120 can control the establishment of an RRC connection with the terminal 200, signal processing of signals received by the receiving unit 112, creation of transmission blocks (TBs), mapping of the transmission blocks to radio resources, etc. The control unit 120 can also control resources related to common signals and transmission / reception channels.

[0033] The storage unit 130 can store, for example, downstream data signals.

[0034] The communication unit 140 connects to a network device (e.g., a higher-level device or another base station device) via a wired or wireless connection to communicate with the device. Data signals received by the communication unit 140 and directed to the terminal 200 can be stored in the storage unit 130. The wireless communication unit 110 and the communication unit 140 may be collectively referred to as the communication unit.

[0035] Next, the terminal 200 will be described. Fig. 3 is a diagram showing an example of a functional configuration block diagram of the terminal 200. As shown in Fig. 3, the terminal 200 includes a communication unit 210, a control unit 220, and a storage unit 230. These components are connected to enable unidirectional or bidirectional input and output of signals and data. The communication unit 210 can be described as being divided into a transmission unit 211 and a reception unit 212.

[0036] The transmitter 211 transmits data signals and control signals by wireless communication via an antenna. Note that the antenna may be common for both transmission and reception. The transmitter 211 transmits uplink signals such as random access procedure signals, RRC layer signals, uplink data signals, and uplink control signals, for example.

[0037] The receiver 212 receives downlink signals transmitted from the base station 100, such as a synchronization signal, SS / PBCH, paging signal, random access procedure signal, downlink data signal, and downlink control signal. The received signals may also include reference signals used for channel estimation and demodulation. The receiver 212 can also receive measurement signals transmitted from the base station 100 and measure the signals.

[0038] The control unit 220 controls the terminal 200. Specifically, the control unit 220 can control the establishment of an RRC connection with the base station 100, signal processing of signals received by the receiving unit 212, creation of transmission blocks (TBs), mapping of the transmission blocks to radio resources, etc. The control unit 220 can also control the measurement of measurement signals in the receiving unit 212.

[0039] The storage unit 230 can store, for example, uplink data signals, and can also store configuration information (or setting information) related to wireless communication transmitted from the base station 100.

[0040] Next, an example of processing in the wireless communication system 1 in the first embodiment will be described with reference to Fig. 4 and Fig. 5. Fig. 4 is a diagram showing an example of a sequence diagram of the wireless communication system in the first embodiment. Fig. 5 is a diagram showing an example of a sequence diagram of the wireless communication system in the first embodiment. Note that parts with the same reference numerals in Fig. 4 and Fig. 5 represent similar processing.

[0041] First, Fig. 4 will be described. Transmitter 111 of base station 100 transmits a first signal (step S10). Also, receiver 212 of terminal 200 receives the first signal (step S10). The first signal includes, for example, configuration information for a second signal and a third signal. The configuration information includes, for example, first information regarding a first resource from which the second signal is transmitted and second information regarding a second resource from which the third signal is transmitted.

[0042] The transmitter 111 of the base station 100 transmits a second signal in accordance with the setting information included in the first signal (step S20). The receiver 212 of the terminal 200 receives the second signal (step S20). The second signal is an example of a signal instructing adaptation of a common signal / channel. For example, when the controller 120 of the base station 100 determines to perform adaptation of the common signal / channel, the controller 120 controls the transmission of the second signal via a first resource in accordance with the first information.

[0043] The control unit 220 of the terminal 200 performs a first process for adapting the common signal / channel (step S30). Note that the first process starts adapting the common signal / channel from a first time in response to reception of the second signal. Note that the adaptation of the common signal / channel is, for example, one or more of SSB (Synchronization Signals / PBCH (Physical Broadcast Channel) Block) adaptation, PRACH (Physical Random Access Channel) adaptation, and paging adaptation. Also, the adaptation of the common signal / channel is an example of adaptive control. Therefore, the adaptation of the common signal / channel may be described as a channel that transmits the third signal or adaptive control for the third signal. Note that the third signal may be an uplink signal or a downlink signal. Also, the third signal may be, for example, SSB, PRACH, or paging.

[0044] For example, when SSB adaptation is performed, the control unit 220 of the terminal 200 updates the SSB reception period. Furthermore, when paging adaptation is performed, the control unit 220 of the terminal 200 updates the paging period or the transmission resource. Furthermore, when the common signal / channel adaptation is SSB adaptation, the second information includes, for example, information on the SSB measurement period or the monitoring period. Furthermore, when the common signal / channel adaptation is paging adaptation, the second information includes, for example, information on the paging monitoring period or the time domain and / or frequency domain resources of the physical downlink control channel for paging.

[0045] Furthermore, the control unit 120 of the base station 100 performs a second process for adapting the common signal / channel (step S40). Note that the second process starts adapting the common signal / channel from a first time in response to transmission of the second signal. Note that the adaptation of the common signal / channel is, for example, one or more of SSB adaptation, PRACH adaptation, and paging adaptation.

[0046] For example, when SSB adaptation is performed, the control unit 120 of the base station 100 updates the SSB reception cycle. Also, for example, when paging adaptation is performed, the control unit 120 of the terminal 100 updates the paging cycle or transmission resources.

[0047] Then, the transmitter 111 of the base station 100 transmits a downlink signal (e.g., SSB, paging signal) at a transmission timing of the downlink signal (e.g., SSB, paging signal) according to the adaptation of the common signal / channel (step S50). Also, the receiver 212 of the terminal 200 receives a third signal at a monitoring timing of the downlink signal (e.g., SSB, paging signal) according to the adaptation of the common signal / channel (step S50).

[0048] Next, Fig. 5 will be described. In Fig. 5, the same processes as those in Fig. 4 are given the same reference numerals and the description thereof will be omitted. The difference between Fig. 4 and Fig. 5 is that Fig. 4 shows an example of adaptation of a common signal / channel to a downlink signal, whereas Fig. 5 shows an example of adaptation of a common signal / channel to an uplink signal.

[0049] The control unit 220 of the terminal 200 performs a first process for adapting the common signal / channel (step S30). Note that the first process starts adapting the common signal / channel from a first time in response to reception of the second signal. Note that the adaptation of the common signal / channel is, for example, one or more of SSB adaptation, PRACH adaptation, and paging adaptation.

[0050] For example, when PRACH adaptation is implemented, the control unit 220 of the terminal 200 updates the resource location for the PRACH. The resource location for the PRACH may be referred to as a RACH opportunity. Furthermore, for example, when common signal / channel adaptation is PRACH adaptation, the second information includes information for configuring a RACH opportunity indicating the resource location for the PRACH. Furthermore, the second information includes, for example, information for enabling / disabling all or part of the RACH opportunities indicating the resource locations for the PRACH provided in the third information. The third information is, for example, information including the configuration of resources for the PRACH. The third information may be, for example, included in the first signal and transmitted, or may be included in an RRC layer signal different from the first signal and transmitted. Furthermore, the second information includes, for example, information on the availability of a RACH opportunity provided in the third information. Furthermore, the second information includes, for example, when a PUSCH resource associated with the PRACH resource is configured, information for enabling / disabling a RACH opportunity and a PUSCH opportunity for transmitting Msg A associated with the RACH opportunity. Furthermore, the second information includes, for example, when a PUSCH resource associated with the PRACH resource is configured by the third information, information for enabling / disabling or availability of a RACH opportunity and a PUSCH opportunity for transmitting Msg A associated with the RACH opportunity. A PUSCH opportunity associated with a RACH opportunity is a PUSCH opportunity included in N slots following a time offset from the start position of the slot to which this RACH opportunity belongs (referred to as a PRACH slot). Here, the time offset and N are configured by the base station.

[0051] Furthermore, the control unit 120 of the base station 100 performs a second process for adapting the common signal / channel (step S40). Note that the second process starts adapting the common signal / channel from a first time in response to transmission of the second signal. Note that the adaptation of the common signal / channel is, for example, one or more of SSB adaptation, PRACH adaptation, and paging adaptation.

[0052] For example, when PRACH adaptation is implemented, the control unit 120 of the base station 100 updates the resource position for the PRACH and performs control so as to monitor the updated resource position for the PRACH.

[0053] Then, the transmitter 211 of the terminal 200 transmits an uplink signal at a timing for transmitting an uplink signal (e.g., a PRACH) according to the adaptation of the common signal / channel (step S60). Also, the receiver 112 of the base station 100 receives a third signal at a monitoring timing for the uplink signal (e.g., a PRACH preamble) according to the adaptation of the common signal / channel (step S60).

[0054] Note that the information for adapting the common signal / channel may be included in the first signal and transmitted, or may be included in a signal different from the first signal and transmitted. Furthermore, the information for adapting the common signal / channel may be determined in advance and stored in advance in the storage unit 130 of the base station 100 and the storage unit 230 of the terminal 200. Furthermore, the information for adapting the common signal / channel may be included in the second signal. The information for adapting the common signal / channel is an example of first information. The first signal is, for example, a signal of the RRC layer. The signal of the RRC layer includes, for example, information of an SIB (System Information Block).

[0055] Furthermore, the control unit 120 of the base station 100 uses information for adapting the common signal / channel to perform settings when the common signal / channel is adapted, and the control unit 220 of the terminal 200 uses information for adapting the common signal / channel to perform settings when the common signal / channel is adapted.

[0056] The information for performing common signal / channel adaptation may be, for example, periodic information for common signal / channel adaptation and resource information (monitoring resource information) for the common signal / channel. The information for performing common signal / channel adaptation may also be, for example, coefficient information. When the information for performing common signal / channel adaptation is a coefficient, for example, the control unit 120 of the base station 100 performs control such that X×Y, obtained by multiplying the period (or interval) X before common signal / channel adaptation by a coefficient Y, becomes the period (or interval) after common signal / channel adaptation. For example, the control unit 220 of the terminal 200 performs control such that X×Y, obtained by multiplying the period (or interval) X before common signal / channel adaptation by a coefficient Y, becomes the period (or interval) after common signal / channel adaptation.

[0057] Here, the second signal, which is a signal instructing adaptation of a common signal / channel, will be described in detail. The second signal is, for example, a downlink control signal, a signal of the RRC layer, or an SI change instruction.

[0058] First, the case where the second signal is a downstream control signal will be described.

[0059] When the second signal is a downlink control signal, a monitoring opportunity for the second signal is set by first information included in the first signal. Note that the monitoring opportunity for the second signal is set, for example, by information on a resource on which the second signal is transmitted, which is included in the configuration information. Note that the first information is the first resource on which the second signal is transmitted, and may include, for example, information for configuring a search space for receiving the second signal.

[0060] Then, the control unit 220 of the terminal 200 performs control so as to monitor the second signal at the monitoring opportunity for the second signal.

[0061] Furthermore, when the second signal is a downlink control signal, an existing Downlink Control Information (DCI) format may be used, or a new DCI format may be defined. When an existing DCI format is used, for example, DCI format 1_0, DCI format 2_7, or DCI format 2_9 is used.

[0062] When DCI format 1_0 is used, for example, paging DCI is used. When paging DCI is used, there are four reserved bits in the short message field (the fifth to eighth bits out of eight bits) (see Non-Patent Document 14). Therefore, one or more of these four reserved bits are used to indicate the adaptation of the common signal / channel. For example, when multiple bits are used, one reserved bit may be used for each type or group of adaptation of the common signal / channel.

[0063] Furthermore, when a paging DCI is used, the indication may be made using, for example, reserved bits in the short message indicator field. For example, in the short message indicator field, bits "00" are reserved bits (see Non-Patent Document 6). Therefore, when the bits in the short message indicator field indicate "00", it may indicate that adaptation of the common signal / channel is indicated.

[0064] Furthermore, when a paging DCI is used, an existing field may be interpreted as a new field. For example, when common signal / channel adaptation is configured, a part of the existing field may be used as a new field for instructing common signal / channel adaptation. Note that the common signal / channel adaptation may be configured via at least one of the first signal and a signal different from the first signal, for example.

[0065] Note that when interpreting an existing field as a new field, it can be used when the configuration corresponding to the existing field and the configuration corresponding to the adaptation of common signals / channels are not set at the same time. For example, when the existing field is a TRS availability indication field, the configuration related to TRS and the configuration corresponding to the adaptation of common signals / channels are not set at the same time.

[0066] When DCI format 2-7 is used, for example, PEI (Paging Early indicator) is used. Here, the format when PEI is used as the information included in the second signal will be described with reference to Fig. 6. Fig. 6 is a diagram showing an example of the format of the information included in the second signal.

[0067] FIG. 6A shows an example in which a paging indication and an adaptation indication are included in a segment corresponding to each group of terminals 200 in a paging indication field.

[0068] For example, when terminal 200 belongs to group 1 (UE Group 1), in order to read information in segment 1, base station 100 transmits information instructing terminal 200 to adapt a common signal / channel to terminal 200, including the information in the adaptation instruction in segment 1. Furthermore, terminal 200 executes a first process in response to the adaptation instruction.

[0069] 6B is a diagram showing an example in which an adaptation indication field is added after a paging indication field. Note that the adaptation indication field may be added before the paging indication field.

[0070] For example, base station 100 transmits information in an adaptation instruction field that instructs terminal 200 to adapt a common signal / channel. Terminal 200 also performs a first process in accordance with the information in the adaptation instruction field.

[0071] When DCI formats 2 to 9 are used, for example, other group-common DCI is used.

[0072] The DCI format to be used may be changed depending on the RRC state of terminal 200. For example, when the RRC state of terminal 200 is an idle state or an inactive state, a paging DCI or a PEI is used to instruct adaptation of a common signal / channel. Also, for example, when the RRC state of terminal 200 is a connected state, a paging DCI or other group-common DCI is used to instruct adaptation of a common signal / channel.

[0073] In addition, a new RNTI may be defined for a signal that instructs adaptation of a common signal / channel, and downlink control information scrambled using the new RNTI may be included in the second signal to instruct adaptation of the common signal / channel.

[0074] Next, the case where the second signal is an SIB will be described.

[0075] When the second signal is an SIB, for example, base station 100 instructs terminal 200 to perform monitoring for SI acquisition via the first signal. Note that, for example, terminal 200 may perform monitoring for SI acquisition when common signal / channel adaptation is configured via the first signal. In short, configuring common signal / channel adaptation instructs monitoring for SI acquisition.

[0076] Then, the control unit 220 of the terminal 200 determines whether new SI is being transmitted at the timing of acquiring the SI. Furthermore, when the control unit 120 of the base station 100 determines to perform common signal / channel adaptation, it transmits an SIB including new SI at the timing closest to the timing when the terminal 200 acquires the SI.

[0077] For example, when PRACH adaptation is implemented, the control unit 220 of the terminal 200 receives the SIB at the timing of SIB acquisition before performing the RACH procedure. After receiving the SIB, the control unit 220 selects a RACH opportunity according to the PRACH resources indicated in the SIB, and transmits a PRACH preamble signal.

[0078] Next, a case where the second signal is a signal of the RRC layer will be described.

[0079] When the second signal uses a signal of the RRC layer, for example, a new message may be defined, or a new information element may be added to an existing RRC message.

[0080] Note that, to use an RRC layer signal as the second signal, it is preferable that the RRC state of the terminal 200 is an RRC connected state. Therefore, for example, the type of signal used to transmit the second signal may be changed depending on the state of the terminal 200. For example, when the RRC state of the terminal 200 is an RRC connected state, the base station 100 transmits the second signal as an RRC layer signal. Furthermore, for example, when the RRC state of the terminal 200 is an RRC idle state or an inactive state, the base station 100 transmits the second signal as a downlink control signal or an SIB.

[0081] As described above, in the first embodiment, after the terminal 200 receives the second signal, the common signal / channel adaptation can be performed from the first time. Therefore, for example, the time from when the base station 100 determines to perform common signal / channel adaptation to when the common signal / channel adaptation is performed can be shortened. Furthermore, it is possible to provide a method that enables the base station 100 and the terminal 200 to share the common signal / channel adaptation between them. Embodiment 2

[0082] In the first embodiment, an example has been described in which terminal 200 performs adaptation of the common signal / channel from the first time after receiving the second signal. In the second embodiment, specific processing using the first time will be described. Note that in the second embodiment, the wireless communication system, base station, and terminal are the same as those in the first embodiment, and therefore description thereof will be omitted.

[0083] The first time period in the second embodiment will be described with reference to Fig. 7. Fig. 7 is a diagram showing an example of the start timing of adaptation of a common signal / channel. An example in which the same start time is set for terminals 200 in cell C10 will be described. Two examples of the same start time will be described.

[0084] 7A shows an example in which the start timing of a modification period is set to a first time. For example, terminal 200A receives a second signal from base station 100 at time T1 of modification period #n, terminal 200B receives a second signal from base station 100 at time T2 of modification period #n, and terminal 200B receives a second signal at time T3 of modification period #n.

[0085] Then, base station 100, terminal 200A, terminal 200B, and terminal 200C set the start timing of the next correction period #n+1 as the first time and apply common signal / channel adaptation. Therefore, for example, terminal 200A applies common signal / channel adaptation after time t1 seconds. Also, for example, terminal 200B applies common signal / channel adaptation after time t2 seconds. Also, terminal 200C applies common signal / channel adaptation after time t3 seconds.

[0086] 7A, the base station 100 can adapt the common signal / channel from the start of the next modification period after the modification period in which the base station 100 has determined to apply the adaptation of the common signal / channel. Note that modification period #n is an example of a first period, and modification period #n+1 is an example of a second period.

[0087] 7B shows an example in which the start timing of a cycle (e.g., a DRX cycle or a paging cycle) within a modification period is set to the first time. For example, terminal 200A receives a second signal from base station 100 at time T4 within cycle #m of modification period #n, and terminal 200B receives a second signal from base station 100 at time T5 within cycle #m of modification period #n.

[0088] Then, the base station 100, the terminal 200A, and the terminal 200B set the start timing of the next cycle #m+1 as the first time and apply common signal / channel adaptation. Therefore, for example, the terminal 200A applies common signal / channel adaptation after time t4 seconds. Also, for example, the terminal 200B applies common signal / channel adaptation after time t5 seconds. Therefore, it is possible to apply common signal / channel adaptation as early as time t6 from the start timing of the next correction period #n+1.

[0089] Here, the relationship between the start times of common signal / channel adaptation will be described with reference to Figures 7 and 8. Figure 8 is a diagram showing an example of the start timing of common signal / channel adaptation. Note that Figure 8 shows an example of performing common signal / channel adaptation using a method of executing SI acquisition processing after a predetermined time has elapsed after receiving a signal instructing an SI change.

[0090] 8, terminal 200 is configured with a time D1 for monitoring a signal instructing an SI change and a time S1 for receiving the SI within modification period #n. Also, a time D2 for monitoring a signal instructing an SI change and a time S2 for receiving the SI within modification period #n+1. Note that time D1 is a first interval from the start timing of modification period #n, and time S1 is a second interval from the start timing of modification period #n. Also, time D2 is a first interval from the start timing of modification period #n+1, and time S2 is a second interval from the start timing of modification period #n+1.

[0091] In the case of Fig. 8, when terminal 200 receives a signal instructing SI change at time D1, it receives SI at time S2 of the next correction period #n+1 and applies common signal / channel adaptation. Therefore, common signal / channel adaptation is performed after time S2.

[0092] Comparing the timing at which common signal / channel adaptation is applied in FIG. 7A and FIG. 8, it is found that adaptation is applied about a second interval earlier in FIG. 7A.

[0093] Comparing the timing at which common signal / channel adaptation is applied in FIG. 7B and FIG. 8, it can be seen that adaptation in FIG. 7B is performed earlier by the sum of time t6 and the second interval.

[0094] In this way, by defining the beginning of the periodically set information as the first time, the same start time is set for all terminals 200 in cell C10. Note that the end of the periodically set information may also be defined as the first time. In this case, the end may be the end of the period in which the second signal was received, or the end of the period following the period in which the second signal was received.

[0095] As described above, in the second embodiment, after the terminal 200 receives the second signal, the terminal 200 can perform common signal / channel adaptation from the first time common to the terminal 200. Therefore, for example, the time from when the base station 100 determines to perform common signal / channel adaptation to when the common signal / channel adaptation is performed can be shortened. Furthermore, it is possible to provide a method that enables the base station 100 and the terminal 200 to share common signal / channel adaptation. Embodiment 3

[0096] In the first embodiment, an example has been described in which terminal 200 performs adaptation of a common signal / channel from a first time after receiving a second signal. In the second embodiment, an example has been described in which terminal 200 sets a common time as a specific example of the first time. In the third embodiment, another example of specific processing using the first time will be described. Note that in the third embodiment, the wireless communication system, base station, and terminal are similar to those in the first and second embodiments, and therefore description thereof will be omitted.

[0097] In the third embodiment, an example will be described in which the first time period is set in accordance with the timing at which the second signal is received.

[0098] The first time period in the third embodiment will be described with reference to Fig. 9. Fig. 9 is a diagram showing an example of the start timing of adaptation of a common signal / channel. In the third embodiment, an example will be described in which the first time period is set according to the timing of receiving the second signal. Note that Fig. 9 shows an example in the case of PRACH adaptation.

[0099] In Fig. 9, Association period #1 and Association period #2 are set within an Association pattern period. Association period #1 includes Frame #0 and Frame #1. Association period #2 includes Frame #2 and Frame #3. Six RACH opportunities (RACH Occasions or PRACH Occasions or ROs) are set per Frame. For example, RO #1 to RO #6 are configured in Frame #0, RO #7 to RO #12 are configured in Frame #1, RO #13 to RO #18 are configured in Frame #2, and RO #19 to RO #24 are configured in Frame #4. Furthermore, the period in which each SSB index is mapped once is called a mapping cycle. For example, if two SSB indices are mapped to one RACH opportunity, in Frame #0, SSB0 / 1 is mapped to RO #3, SSB2 / 3 is mapped to RO #4, SSB4 / 5 is mapped to RO #5, and SSB6 / 7 is mapped to RO #6. The period including RO #3, RO #4, RO #5, and RO #6 is set as a mapping cycle. Although not shown, a period including an RO in which SSB0 / 1, SSB2 / 3, SSB4 / 5, and SSB6 / 7 in Frame #1 to Frame #3 are mapped is also set as a mapping cycle. The association period indicates a period in which each SSB index is mapped to an RO at least once. The association period includes multiple mapping cycles. The association pattern period is a period that combines different association periods.

[0100] Here, when terminal 200 receives the second signal in Frame #0, the first time period is determined according to the timing at which the second signal is received and the type of common signal / channel.

[0101] For example, the base station 100 and the terminal 200 change the start time of the first time period depending on the period (e.g., mapping cycle, association period, or association pattern period) at which the SSB index is mapped to the RACH opportunity or the type of random access (e.g., 4-step RACH or 2-step RACH).

[0102] For example, when the period in which SSB indices are mapped to RACH opportunities or the type of random access is the first case (or the first condition), adaptation of the common signal / channel begins at time A1, which is the start timing of the next mapping cycle.

[0103] Furthermore, for example, when the period in which SSB indices are mapped to RACH opportunities or the type of random access is the second case (or the second condition), time A2 is set as the first time, and adaptation of the common signal / channel is started. Note that time A1 is the start timing of the next association period.

[0104] Furthermore, for example, when the period in which SSB indices are mapped to RACH opportunities or the type of random access is the third case (or the third condition), adaptation of the common signal / channel is started at time A3, which is the first time. Note that time A3 is the start timing of the next association pattern period.

[0105] Also, for example, if the period for mapping SSB indices to RACH opportunities or the type of random access is the fourth case (or the fourth condition), after receiving the second signal, adaptation of the common signal / channel is started with the next RACH opportunity in the time domain as the first time.

[0106] The first to fourth cases may be set, for example, by the first signal. For example, the RACH opportunities corresponding to SSB0 / 1 and SSB2 / 3 correspond to the first case, the RACH opportunities corresponding to SSB4 / 5 correspond to the second case, and the RACH opportunities corresponding to SSB6 / 7 correspond to the third case. This allows for faster adaptation of common signals / channels to a portion of the RO.

[0107] Furthermore, when SSB adaptation is applied, base station 100 or terminal 200 may determine the first time period in consideration of, for example, an SSB transmission opportunity and processing times for Layer 1 / Layer 3 measurements. Layer 1 is the physical layer, and Layer 3 is the RRC layer.

[0108] For example, the start timing of an SSB transmission opportunity after the processing time for Layer 1 / Layer 3 measurement is completed at the time when the second signal is received is defined as the first time. For example, if the processing time for Layer 1 / Layer 3 measurement performed at SSB transmission opportunity #1 is completed by the next SSB transmission opportunity #2, the start timing of the next SSB transmission opportunity #2 is defined as the first time. Also, for example, if the processing time for Layer 1 / Layer 3 measurement performed at SSB transmission opportunity #1 is not completed by the next SSB transmission opportunity #2 but is completed by the next SSB transmission opportunity #3 after SSB transmission opportunity #2, the start timing of the next SSB transmission opportunity #3 after SSB transmission opportunity #2 is defined as the first time.

[0109] As described above, in the third embodiment, after the terminal 200 receives the second signal, it is possible to perform adaptation of the common signal / channel from the first time corresponding to the reception timing of the second signal. Therefore, for example, it is possible to shorten the time from when the base station 100 determines to perform adaptation of the common signal / channel to when the adaptation of the common signal / channel is performed. Furthermore, it is possible to provide a method that enables the base station 100 and the terminal 200 to share the adaptation of the common signal / channel between them. Hardware configuration of each device in each embodiment

[0110] The hardware configuration of each device in the wireless communication system of each embodiment will be described with reference to FIGS.

[0111] Fig. 10 is a diagram showing an example of the hardware configuration of base station 100. As shown in Fig. 10, base station 100 has, as hardware components, for example, an RF (Radio Frequency) circuit 320 equipped with an antenna 310, a CPU (Central Processing Unit) 330, a DSP (Digital Signal Processor) 340, a memory 350, and a network IF (Interface) 360. The CPU is connected via a bus so as to enable input and output of various signals and data signals. The memory 350 includes at least one of a RAM (Random Access Memory) such as an SDRAM (Synchronous Dynamic Random Access Memory), a ROM (Read Only Memory), and a flash memory, and stores programs, control information, and data signals.

[0112] The correspondence between the functional configuration of the base station 100 shown in Fig. 2 and the hardware configuration of the base station 100 shown in Fig. 10 will be described. The transmitter 111 and receiver 112 (or the wireless communication unit 110) are realized by, for example, an RF circuit 320, or an antenna 310 and an RF circuit 320. The control unit 120 is realized by, for example, a CPU 330, a DSP 340, a memory 350, a digital electronic circuit (not shown), etc. Examples of the digital electronic circuit include an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), and an LSI (Large Scale Integration). The storage unit 130 is realized by, for example, the memory 350. The communication unit 140 is realized by, for example, the network IF 360 .

[0113] Fig. 11 is a diagram showing an example of the hardware configuration of terminal 200. As shown in Fig. 11, terminal 200 has, as hardware components, an RF circuit 420 including, for example, an antenna 410, a CPU 430, a DSP 440, and a memory 450. Memory 450 includes at least one of a RAM such as an SDRAM, a ROM, and a flash memory, and stores programs, control information, and data signals.

[0114] The correspondence between the functional configuration of the terminal 200 shown in Fig. 3 and the hardware configuration of the terminal 200 shown in Fig. 11 will be described. The transmitter 211 and receiver 212 (or communication unit 210) are realized by, for example, an RF circuit 420, or an antenna 410 and an RF circuit 420. The control unit 220 is realized by, for example, a CPU 430, a DSP 440, a memory 450, a digital electronic circuit (not shown), etc. Examples of the digital electronic circuit include an ASIC, an FPGA, and an LSI. The storage unit 230 is realized by, for example, the memory 450.

[0115] The embodiments may be combined as appropriate within a range that does not cause any contradiction.

[0116] In each embodiment, examples of a base station and a terminal are described, but the disclosed technology is not limited to this and can be applied to various devices such as electronic devices mounted on automobiles, trains, airplanes, artificial satellites, etc., electronic devices transported by drones, etc., robots, AV equipment, home appliances, office equipment, vending machines, and other household equipment.

[0117] Furthermore, although the embodiments have been described using fifth-generation mobile communications as an example, the application of the disclosed technology is not limited to this. For example, the disclosed technology may be applied to mobile communications of different generations, such as sixth and seventh generations.

[0118] 1 Wireless communication system 100 Base station C10 Cell 110 Wireless communication unit 111 Transmitter 112 Receiver 120 Control unit 130 Memory unit 140 Communication unit 200, 200A, 200B, 200C Terminal 210 Communication unit 211 Transmitter 212 Receiver 220 Control unit 230 Memory unit 310 Antenna 320 RF circuit 330 CPU 340 DSP 350 Memory 360 Network IF 410 Antenna 420 RF circuit 430 CPU 440 DSP 450 Memory

Claims

1. A terminal having: a receiving unit that receives a first signal including first information regarding a first resource on which a second signal is transmitted and second information regarding a second resource on which a third signal is transmitted; and a control unit that, when the second signal is received via the first resource according to the first information, performs adaptive control to adjust the second resource on which the third signal is transmitted from a first time.

2. The terminal according to claim 1, wherein the second signal includes third information instructing the implementation of the adaptive control.

3. The terminal according to claim 1, wherein the first signal is a signal of an RRC layer, and the third signal is one of SSB, paging, and PRACH.

4. The terminal according to claim 1, wherein the first time is the timing of the beginning of a second interval that is the interval following the first interval in which the second signal was received.

5. The terminal according to claim 1, further comprising a transmitting unit that transmits the third signal, wherein the control unit determines the first time period according to the timing of receiving the second signal and the third signal.

6. The terminal according to claim 1, wherein the receiving unit receives the third signal, and the control unit determines the first time period according to a timing of receiving the second signal and a processing time for the second signal.

7. A base station having: a transmitting unit that transmits a first signal including first information regarding resources on which a second signal is transmitted and second information regarding resources on which a third signal is transmitted; and a control unit that, when it is determined that adaptive control for adjusting the position of the resources on which the third signal is transmitted is to be performed from a first time, controls the second signal to be transmitted via resources according to the first information.

8. A wireless communication system having: a transmitter that transmits a first signal including first information regarding resources on which a second signal is to be transmitted and second information regarding resources on which a third signal is to be transmitted; and a terminal that, when receiving the second signal via resources according to the first information, performs adaptive control from a first time to adjust the position of the resources on which the third signal is to be transmitted.

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