Terminal, base station, and wireless communication system

Abstract

This terminal has a first reception unit, a second reception unit, and a control unit. The first reception unit receives a first signal including first setting information for setting a first monitoring opportunity for a second signal and second setting information for setting a second monitoring opportunity for the second signal. The second reception unit receives the second signal. The control unit performs control so as to monitor the first monitoring opportunity and the second monitoring opportunity and performs control so as to activate the first reception unit in order to receive a third signal when the second signal is detected during the first monitoring opportunity or the second signal is detected during the second monitoring opportunity.

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). Furthermore, the communication standards for the fifth generation mobile communication also prescribe techniques for reducing the power consumption of terminal devices.

[0004] Furthermore, the 3GPP (3rd Generation Partnership Project (registered trademark)) is studying low-power wake-up signal and receiver as a new technology for reducing terminal power consumption (Non-Patent Document 15). To implement low-power wake-up signal and receiver, a terminal includes a receiver with low power consumption (low-power receiver) and a receiver for data communication (main radio unit). Here, when not performing data communication (e.g., when in an idle state), the terminal operates the low-power receiver and controls the main radio unit not to operate. Then, when the terminal receives a wake-up signal via the low-power receiver, it activates the main radio unit.

[0005] Furthermore, 3GPP is studying a method of associating and controlling an opportunity (LO (LP-WUS occasion) or MO (LP-WUS monitoring occasion)) for monitoring a signal (hereinafter referred to as LP-WUS (Low Power Wake Up Signal)) by a low-power receiver with an opportunity (PO (Paging occasion)) for monitoring paging by a main radio unit (Non-Patent Document 16).

[0006] 3GPP TS 37.324 V17.0.03GPP TS 37.340 V17.7.03GPP TS 38.201 V17.0.03GPP TS 38.202 V17.5.03GPP TS 38.211 V17.6.03GPP TS 38.212 V17.7.03GPP TS 38.213 V17.8.03GPP TS 38.214 V17.8.03GPP TS 38.215 V17.4.03GPP TS 38.300 V17.7.03GPP TS 38.321 V17.7.03GPP TS 38.322 V17.3.03GPP TS 38.323 V17.5.03GPP TS 38.331 V17.7.03GPP TR 38.869 V18.0.0R1-2405682

[0007] However, the discussion of LP-WUS has just begun, and the details have not yet been decided. Therefore, Non-Patent Document 16 assumes several patterns for the correspondence between the opportunities for LP-WUS monitoring and the opportunities for paging monitoring, but does not yet take into consideration actual operation.

[0008] Therefore, it may not be possible to perform control using LP-WUS depending on the situation, which may result in an unnecessary load on the terminal or a decrease in resource utilization efficiency.

[0009] Therefore, control related to LP-WUS needs to be performed according to the situation.

[0010] The disclosed technology has been made in consideration of the above, and provides a method for controlling LP-WUS in accordance with the situation.

[0011] In one aspect, a terminal is provided having: a first receiving unit that receives a first signal including first setting information that sets a first monitoring opportunity for a second signal and second setting information that sets a second monitoring opportunity for the second signal; a second receiving unit that receives the second signal; and a control unit that controls the first receiving unit to start up in order to receive a third signal when the second signal is detected at the first monitoring opportunity or when the second signal is detected at the second monitoring opportunity.

[0012] In controlling the LP-WUS, it is possible to perform control according to the situation.

[0013] FIG. 1 is a diagram showing an example of a network configuration according to a first embodiment. FIG. 2 is a diagram showing an example of a functional configuration block diagram of a base station in a 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 a wireless communication system according to the first embodiment. FIG. 4 is a diagram showing an example of a sequence of a wireless communication system according to the first embodiment. FIG. 5 is a diagram showing an example of a monitoring opportunity for a second signal. FIG. 6 is a diagram showing an example of a sequence of a wireless communication system according to a second embodiment. FIG. 7 is a diagram showing an example of a sequence of a wireless communication system according to a third embodiment. FIG. 8 is a diagram showing an example of a processing flow of a terminal according to the third embodiment. FIG. 9 is a diagram showing an example of a hardware configuration of a base station. FIG. 10 is a diagram showing an example of a hardware configuration of a terminal.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] [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.

[0018] Non-Patent Document 16 assumes several patterns for the opportunity to monitor LP-WUS and the opportunity to monitor paging. For example, a first assumed pattern option is to make the opportunity to monitor LP-WUS the same in terminals that have the same opportunity to monitor paging. Also, for example, a second assumed pattern option is to make the opportunity to monitor LP-WUS the same in terminals that have different opportunity to monitor paging.

[0019] For example, in the first option, if it is desired to transmit paging to multiple terminals that have different opportunities to monitor paging, it is necessary to transmit multiple LP-WUSs, which increases overhead.

[0020] On the other hand, for example, in the case of the second option, if a paging message is to be sent to one of multiple terminals that have different opportunities to monitor paging, one LP-WUS will activate the main receivers of multiple terminals. In this case, the main receivers of terminals that do not receive paging messages will also be activated, resulting in increased power consumption of the terminals.

[0021] Furthermore, the entry condition for entering a state in which a low-power receiver receives a signal is that, as a result of RRM (Radio Resource Measurement), the measured SS / PBCH (Synchronization Signal / Physical Broadcast Channel) value (for example, SS-RSRP (SSB (SS / PBCH Block) - Reference Signal Received Power)) exceeds a set threshold. Here, for example, if the entry condition is met before the opportunity to monitor LP-WUS arises after receiving LP-WUS, the state in which a low-power receiver receives a signal will be entered before receiving paging. Therefore, in order to have the main receiver receive the signal again, LP-WUS will be transmitted, and the same thing as above may occur. As a result, the terminal state transitions are repeated, which not only wastes resources but also may increase the terminal's power consumption.

[0022] In summary, control is required according to the status of terminals that have transitioned from low-power receivers to main receivers using LP-WUS. For example, it is necessary to implement control related to LP-WUS taking into consideration at least one of the following: the number of terminals that the base station wants to transition from low-power receivers to main receivers, the position of the terminal's paging monitoring opportunity, or the measurement time using SS / PBCH. As mentioned above, this problem was newly discovered by the inventors as a result of a detailed study of the prior art, and was not previously known. Hereinafter, each embodiment of the present application for solving at least one of these problems will be described in order. First Embodiment

[0023] 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 and 200B. The base station 100 forms a cell C10. The terminals 200A and 200B are located within the cell C10. When there is no need to distinguish between the terminals 200A and 200B, they will be simply referred to as terminals 200.

[0024] 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 a communication device having various functions, such as a function of relaying signals, and may be referred to as a wireless communication device, a communication device, a receiving device, a repeater, etc. The terminal 200 may be a wireless terminal such as various devices with wireless communication functions, such as a mobile phone, a smartphone, a PDA (Personal Digital Assistant), a personal computer, a vehicle, an airplane, a drone, etc., or devices (sensor devices, etc.) installed in robots, 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.

[0025] 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.

[0026] 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.

[0027] On the other hand, the terminal 200 communicates with the base station 100 via wireless communication.

[0028] Next, the base station 100 will be described. Fig. 2 is a diagram showing an example of a functional configuration 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.

[0029] The wireless communication unit 110 is composed of a transmission unit 111 and a reception unit 112, and performs wireless communication with the terminal 200. Specifically, the transmission unit 111 transmits to the terminal 200, for example, downlink signals such as measurement signals (e.g., SS / PBCH, reference signals) that the terminal 200 is to measure, random access procedure signals, RRC (Radio Resource Control) layer signals, downlink data signals, and downlink control signals. Note that the transmission unit 111 transmits an LP-WUS (Low Power Wake Up Signal) to the terminal 200.

[0030] 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.

[0031] 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 a transmission block (TB), mapping of the transmission block to radio resources, etc. Furthermore, the control unit 120 can control the transmission of an LP-WUS to a terminal 200 whose main receiver is not activated.

[0032] The storage unit 130 can store, for example, downstream data signals.

[0033] 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.

[0034] Next, the terminal 200 will be described. FIG. 3 is a diagram showing an example of a functional configuration 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 separately as a transmission unit 211, a first receiving unit 212, and a second receiving unit 213. For example, the first receiving unit 212 is an example of a main receiver. The second receiving unit 213 is an example of a low-power receiver. The low-power receiver may also be described as a wake-up receiver. The second receiving unit 213 may also be described as a receiving unit that consumes less power than the first receiving unit 212.

[0035] 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.

[0036] The first receiving unit 212 receives downlink signals, such as a random access procedure signal, a downlink data signal, and a downlink control signal, transmitted from the base station 100. The received signals may include, for example, reference signals used for channel estimation and demodulation. The first receiving unit 212 can also receive measurement signals transmitted from the base station 100 and measure the signals.

[0037] The second receiving unit 213 receives, for example, an LP-WUS transmitted from the base station 100 .

[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 first receiving unit 212, creation of transmission blocks (TB), mapping of the transmission blocks to radio resources, and the like. The control unit 220 can also control measurement of measurement signals in the first receiving unit 212. The control unit 220 can control the activation of the first receiving unit 212 and the second receiving unit 213. For example, when the second receiving unit 213 receives an LP-WUS, the control unit 220 controls the activation of the first 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, a processing flow of the wireless communication system 1 in the first embodiment will be described with reference to Fig. 4. Fig. 4 is a diagram showing an example of a sequence diagram of the wireless communication system 1.

[0041] The transmitter 111 of the base station 100 transmits a first signal to the terminal 200 (step S10). The first receiver 212 of the terminal 200 receives the first signal (step S10). The first signal includes, for example, first setting information for setting a first monitoring opportunity for the second signal and second setting information for setting a second monitoring opportunity for the second signal. The first signal is, for example, a broadcast signal, a Master Information Block (MIB), or a System Information Block x (x is an integer) (SIBx). The second signal is, for example, a Wake-Up signal. The controller 220 of the terminal 200 that has received the first signal sets a first monitoring opportunity for the second signal in accordance with the first setting information, and sets a second monitoring opportunity for the second signal in accordance with the second setting information.

[0042] The control unit 220 of the terminal 200 performs a first process, which is a process for transitioning from a first state to a second state (step S20). The first state is, for example, a state in which a signal can be received by the first receiving unit 212 corresponding to the main receiver. The second state is, for example, a state in which a signal cannot be received by the first receiving unit 212 corresponding to the main receiver, but a signal can be received by the second receiving unit 213 corresponding to the low-power receiver. The first state may be referred to as an active state, and the second state may be referred to as a low-power state. When the terminal 200 is in the second state, the control unit 220 of the terminal 200 controls the second receiving unit 213 to monitor the first monitoring opportunity and the second monitoring opportunity. When the terminal 200 is in the second state, the control unit 220 of the terminal 200 controls the second receiving unit 213 not to receive or monitor signals via the first receiving unit 212. The first process is, for example, a process of transitioning from the first state to the second state when the wireless quality exceeds a predetermined value or is equal to or greater than a predetermined value after the terminal 200 transitions to an idle state or an inactive state.

[0043] The control unit 120 of the base station 100 performs a second process to determine a resource for transmitting a second signal from a plurality of resources including a resource corresponding to the first monitoring opportunity set using the first signal and a resource corresponding to the second monitoring opportunity for the terminal 200 in the second state (step S30).

[0044] The transmitter 111 of the base station 100 transmits the second signal using the resource determined in the second process (step S40). The second receiver 213 of the terminal 200 receives the second signal (step S40). Note that the base station 100 can cause the terminal 200 to perform control to receive the third signal by transmitting the second signal using the resource corresponding to either the first monitoring opportunity or the second monitoring opportunity.

[0045] The control unit 220 of the terminal 200 performs a third process including a process of receiving a signal via the first receiving unit 212 and monitoring the signal (step S50).

[0046] After transmitting the second signal, the transmitter 111 of the base station 100 transmits a third signal (step S60). Furthermore, the first receiver 212 of the terminal 200 receives the third signal (step S60). The third signal is, for example, a paging message or a paging Physical Downlink Control Channel (PDCCH). Note that the resource on which the third signal is transmitted may or may not be related to the resource on which the second signal is received. Furthermore, the monitoring opportunity for the third signal is set, for example, by the first signal or a signal different from the first signal (for example, if the first signal is SIBx, the signal different from the first signal is SIBy or another RRC layer signal). Furthermore, the monitoring opportunity for the third signal is, for example, a paging occasion (PO). The third signal monitoring opportunity is an example of a third monitoring opportunity.

[0047] Here, the second process will be described in detail using FIG. 5. FIG. 5 is a diagram showing an example of a monitoring opportunity for the second signal. FIG. 5 shows an example in which terminal 200A and terminal 200B belong to different groups. Also, in FIG. 5, an example is shown in which LO (LP-WUS Occasion) is composed of multiple MOs (LP-WUS Monitoring Occasions), but LO may be composed of one or more MOs. Also, the second signal is transmitted via the MOs.

[0048] Control unit 220 of terminal 200A controls so that LO #0 is monitored by second receiving unit 213 using the first setting information, and so that LO #1 is monitored by second receiving unit 213 using the second setting information. In short, control unit 220 of terminal 200A controls so that LO #0 and LO #1 are monitored in accordance with the first signal.

[0049] Furthermore, control unit 220 of terminal 200B controls so that LO #2 is monitored by second receiving unit 213 using the first setting information, and so that LO #1 is monitored by second receiving unit 213 using the second setting information. In short, control unit 220 of terminal 200B controls so that LO #2 and LO #1 are monitored in accordance with the first signal.

[0050] Here, when base station 100 wants to transmit a third signal to terminal 200A, it transmits a second signal using MO included in LO #0. In this way, base station 100 can control terminal 200A to perform the third process and can control terminal 200B not to perform the third control.

[0051] Furthermore, when base station 100 wishes to transmit a third signal to terminal 200B, it transmits the second signal using the MO included in LO #2. In this way, base station 100 can control terminal 200B to perform the third process and can control terminal 200A not to perform the third control.

[0052] Furthermore, when base station 100 wishes to transmit a third signal to terminal 200A and terminal 200B, it transmits the second signal using the MO included in LO #1. In this way, base station 100 can control terminal 200A and terminal 200B to perform the third process.

[0053] Although the first and second monitoring opportunities have been described as LOs, the first and second monitoring opportunities may be MOs. Also, the MOs within the same LO may be divided into the first and second monitoring opportunities.

[0054] As described above, in the first embodiment, base station 100 transmits a first signal including first setting information and second setting information to terminal 200. Furthermore, base station 100 transmits a second signal to terminal 200 at either a first monitoring opportunity corresponding to the first setting information or a second monitoring opportunity corresponding to the second setting information. Then, upon receiving the second signal at either the first monitoring opportunity or the second monitoring opportunity, terminal 200 activates first receiving unit 212, which is the main receiver. In this manner, control using LP-WUS can be performed according to the situation. For example, base station 100 can determine resources for transmitting the second signal according to terminal 200 that wishes to transmit a third signal, and activate the main receiver of terminal 200 that wishes to transmit the third signal. Embodiment 2

[0055] In the first embodiment, an example has been described in which base station 100 transmits a first signal including first setting information and second setting information to terminal 200, and sets a first monitoring opportunity according to the first setting information and a second monitoring opportunity according to the second setting information to terminal 200. In the second embodiment, an example will be described in which terminal 200 transitions from a first state to a second state after receiving the second signal. 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.

[0056] The processing flow of the wireless communication system 1 in the second embodiment will be described with reference to Fig. 6. Fig. 6 is a diagram showing an example of a sequence of the wireless communication system in the second embodiment. In Fig. 6, the same processes as those in Fig. 4 are given the same step numbers, and descriptions thereof will be omitted.

[0057] The transmitter 111 of the base station 100 transmits a first signal to the terminal 200 (step S15). The first receiver 212 of the terminal 200 receives the first signal (step S15). The first signal includes, for example, first configuration information for setting a first monitoring opportunity for the second signal. The first signal may or may not include second configuration information for setting a second monitoring opportunity for the second signal.

[0058] 6 , after the control unit 220 of the terminal 200 performs the third process (step S50), there are cases where the control unit 220 does not receive the third signal or fails to receive the third signal in step S60. For this reason, step S60 is indicated by a dotted line.

[0059] The control unit 220 of the terminal 200 performs a fourth process (step S70). The fourth process includes a process of transitioning the state of the terminal 200 from the first state to the second state when at least one of the following conditions is met and a condition for the measurement result of wireless quality is met. Note that satisfying at least one of the following conditions and a condition for the measurement result of wireless quality may also be described as satisfying an entry condition.

[0060] Condition 1: The first receiving unit 212 of the terminal 200 monitors the third signal N times (N is an integer). The value of N may be determined in advance or based on information notified by the base station 100. Condition 2: A predetermined time T elapses after transitioning to the first state. The predetermined time T may be determined in advance or based on information notified by the base station 100. Condition 3: X periods of the SS / PBCH transmission cycle elapse (X is an integer). The value of X may be determined in advance or based on information notified by the base station 100. The SS / PBCH may also be referred to as SSB (SS / PBCH Block). Condition 4: A signal instructing switching to the second state is received. Condition 5: A signal belonging to the "signal type" notified by the third signal is received.

[0061] The signal instructing switching to the second state in condition 4 is, for example, an RRC layer signal or a paging message. In the case of a paging message, for example, it is a paging message including an lpWurSwitchIndication information element in a PagingRecord information element. Furthermore, the signal instructing switching to the second state in condition 4 may be, for example, a signal different from the third signal, or may be included in the third signal and transmitted.

[0062] Condition 5 is, for example, that when the third signal specifies a first type (e.g., ETWS), the control unit 220 of the terminal 200 receives a signal of the first type (e.g., ETWS). The signal of the first type (e.g., ETWS) is, for example, a signal of the RRC layer. The signal of the first type (e.g., ETWS) is transmitted, for example, by SIBx.

[0063] The condition for the measurement result of wireless quality is, for example, that the SS-RSRP exceeds a predetermined threshold or is equal to or greater than a predetermined threshold. The predetermined threshold may be set in an RRC layer signal (the first signal or a signal different from the first signal), or a predetermined value may be used. The SS-RSRP is obtained by measuring, for example, the SS / PBCH. Therefore, the condition for the measurement result of wireless quality can also be described as that the value obtained as a result of measuring the SS / PBCH exceeds or is equal to or greater than a predetermined threshold.

[0064] By setting the condition that at least one of conditions 1 to 5 is satisfied, it is possible to ensure a monitoring opportunity for the third signal. Therefore, it is possible to set the monitoring opportunity for the second signal and the monitoring opportunity for the third signal without worrying about the positions of the monitoring opportunity. Furthermore, since it is possible to ensure a monitoring opportunity for the third signal, it is also possible to prevent, for example, repeated state transitions of terminal 200.

[0065] As described above, in the second embodiment, an entry condition for transitioning terminal 200 from the first state to the second state is set. In this way, control using LP-WUS can be performed according to the situation. For example, terminal 200 can secure a monitoring opportunity for the third signal after receiving the second signal. In addition, the degree of freedom in setting the monitoring opportunity for the second signal and the monitoring opportunity for the third signal can be increased. Embodiment 3

[0066] In the first embodiment, an example has been described in which the base station 100 transmits a first signal including first setting information and second setting information to the terminal 200, and configures the terminal 200 with a first monitoring opportunity according to the first setting information and a second monitoring opportunity according to the second setting information. In the second embodiment, an example has been described in which the terminal 200 transitions from the first state to the second state after receiving a second signal using an entry condition. In the third embodiment, an example will be described in which the first monitoring opportunity is associated with a monitoring opportunity for a third signal, and the second monitoring opportunity is not associated with a monitoring opportunity for the third signal. Note that in the third embodiment, the wireless communication system, the base station, and the terminal are the same as those in the first embodiment, and therefore description thereof will be omitted.

[0067] In the third embodiment, the first setting information is information set for each terminal 200 or a group of terminals 200 (hereinafter referred to as a terminal group), and the second setting information is information set for multiple terminal groups. Also, the second monitoring opportunity according to the second setting information is assumed to be unrelated to the resource for receiving the third signal.

[0068] The processing flow of the wireless communication system 1 in the third embodiment will be described with reference to Fig. 7. Fig. 7 is a diagram showing an example of a sequence of the wireless communication system in the third embodiment. In Fig. 7, the same processes as those in Fig. 4 are given the same step numbers, and descriptions thereof will be omitted.

[0069] 7, after the control unit of terminal 200 performs the third process (step S50), there are cases where the third signal is not received or reception fails in step S60. For this reason, step S60 is indicated by a dotted line. Note that if the third signal is not received, for example, when it is desired to transmit the third signal to a predetermined number or more of multiple terminal groups, transmitting the second signal at the second monitoring opportunity can reduce the overhead caused by the second signal.

[0070] The control unit 220 of the terminal 200 performs a fifth process including a process for transitioning from the first state to the second state (step S80). After the fifth process, the second process and subsequent processes in Fig. 7 are performed, thereby enabling a transition from the second state to the first state. The fifth process includes a process similar to the fourth process.

[0071] The fifth process will now be described with reference to Fig. 8. Fig. 8 is a diagram showing an example of a processing flow of the terminal 200 in the third embodiment.

[0072] The control unit 220 of the terminal 200 determines whether the second signal is received via the first monitoring opportunity (step S81). Note that step S81 may be described as determining whether the second signal is received at the first monitoring opportunity or the second monitoring opportunity.

[0073] When the control unit 220 of the terminal 200 receives the second signal via the first monitoring opportunity (step S81: Yes), the control unit 220 determines whether the first condition is satisfied (step S82).

[0074] If the first condition is not satisfied (step S82: No), the control unit 220 of the terminal 200 repeats step S82. If the first condition is satisfied (step S82: Yes), the control unit 220 of the terminal 200 transitions to the second state (step S84) and ends the process.

[0075] If the second signal is not received via the first monitoring opportunity (step S81: No), the control unit 220 of the terminal 200 determines whether the second condition is met (step S83). Note that the second condition may be different from the first condition. Furthermore, "if the second signal is not received via the first monitoring opportunity" can be rephrased as "if the second signal is received via the second monitoring opportunity."

[0076] If the second condition is not satisfied (step S83: No), the control unit 220 of the terminal 200 repeats step S83. If the second condition is satisfied (step S83: Yes), the control unit 220 of the terminal 200 transitions to the second state (step S84) and ends the process.

[0077] The first condition is, for example, that a condition for the measurement result of wireless quality is satisfied. The condition for the measurement result of wireless quality is, for example, that SS-RSRP exceeds a predetermined threshold or is equal to or greater than a predetermined threshold. The predetermined threshold may be set by a signal of the RRC layer (the first signal or a signal different from the first signal), or a predetermined value may be used.

[0078] The first condition may be to satisfy at least one of the following conditions and to satisfy a condition for a measurement result of wireless quality:

[0079] Condition 1-1: The first receiving unit 212 of the terminal 200 monitors the third signal N1 times (N1 is an integer). The value of N1 may be determined in advance or based on information notified by the base station 100. Condition 2-1: A predetermined time T1 passes after transitioning to the first state. The predetermined time T1 may be determined in advance or based on information notified by the base station 100. Condition 3-1: X1 periods pass in the SS / PBCH transmission period (X1 is an integer). The value of X1 may be determined in advance or based on information notified by the base station 100. The SS / PBCH may be referred to as SSB (SS / PBCH Block). Condition 4-1: A signal instructing switching to the second state is received. Condition 5-1: A signal belonging to the "signal type" notified by the third signal is received.

[0080] The second condition is, for example, that a condition for the measurement result of radio quality is satisfied. The condition for the measurement result of radio quality is, for example, that SS-RSRP exceeds a predetermined threshold or is equal to or greater than a predetermined threshold. The predetermined threshold may be set by a signal of the RRC layer (the first signal or a signal different from the first signal), or a predetermined value may be used.

[0081] The second condition may be that one or more of the following conditions are satisfied, and that a condition for a measurement result of wireless quality is satisfied. Condition 1-2: The first receiving unit 212 of the terminal 200 monitors the third signal N2 times (N2 is an integer). The value of N2 may be determined in advance or based on information notified by the base station 100. Condition 2-2: A predetermined time T2 elapses after transitioning to the first state. The predetermined time T2 may be determined in advance or based on information notified by the base station 100. Condition 3-2: X2 periods of the SS / PBCH transmission period elapse (X2 is an integer). The value of X2 may be determined in advance or based on information notified by the base station 100. The SS / PBCH may also be referred to as SSB (SS / PBCH Block). Condition 4-2: A signal instructing switching to the second state is received. Condition 5-2: A signal belonging to the "signal type" notified in the third signal is received.

[0082] When N1 and N2 are used as conditions, N2 is set to be equal to or greater than N1. When T1 and T2 are used as conditions, T2 is set to be equal to or greater than T1. When X1 and X2 are used as conditions, X2 is set to be equal to or greater than X1.

[0083] This is because, in the case of the second monitoring opportunity, there is a possibility that the time from when the second signal is received at the second monitoring opportunity to when the terminal 200 receives the third signal may be long.

[0084] As described above, in the third embodiment, the base station 100 transmits a first signal including first setting information and second setting information to the terminal 200. The base station 100 also transmits a second signal to the terminal 200 at either the first monitoring opportunity corresponding to the first setting information or the second monitoring opportunity corresponding to the second setting information. Then, upon receiving the second signal at either the first monitoring opportunity or the second monitoring opportunity, the terminal 200 activates the first receiving unit 212, which is the main receiver. In this manner, control using LP-WUS can be performed according to the situation. For example, the base station 100 can determine resources for transmitting the second signal according to the terminal 200 that wishes to transmit the third signal, and activate the main receiver of the terminal 200 that wishes to transmit the third signal. Embodiment 4

[0085] In the first embodiment, an example has been described in which the base station 100 transmits a first signal including first setting information and second setting information to the terminal 200, and configures a first monitoring opportunity corresponding to the first setting information and a second monitoring opportunity corresponding to the second setting information in the terminal 200. In the second embodiment, an example has been described in which the terminal 200 transitions from the first state to the second state after receiving a second signal using an entry condition. In the third embodiment, an example has been described in which the first monitoring opportunity is associated with a monitoring opportunity for a third signal, and the second monitoring opportunity is not associated with a monitoring opportunity for the third signal. In the fourth embodiment, a method for configuring a monitoring opportunity for a second signal will be described. Note that in the fourth embodiment, the wireless communication system, the base station, and the terminal are similar to those in the first embodiment, and therefore description thereof will be omitted.

[0086] In addition, in the fourth embodiment, similarly to the third embodiment, the first setting information is information set for each terminal 200 or a group of terminals 200 (hereinafter referred to as a terminal group), and the second setting information is information set for multiple terminal groups. Also, it is assumed that the second monitoring opportunity according to the second setting information is not related to the resource for receiving the third signal.

[0087] In the fourth embodiment, an example will be described in which the first monitoring opportunity and the second monitoring opportunity are set as LO. Three examples of setting LO will be described. The settings to be described are set, for example, according to the first setting information or the second setting information.

[0088] (First Example) In the first example, a first monitoring opportunity and a second monitoring opportunity are set independently. The first monitoring opportunity is set, for example, using a terminal identifier for each terminal. For the first monitoring opportunity, for example, a module function is used for the terminal identifier to divide the terminals into groups, and an LO corresponding to each terminal group is set. Note that the first setting information is, for example, information indicating the LO period, offset value, and LO corresponding to each terminal group.

[0089] On the other hand, the second monitoring opportunity is set using, for example, an offset value and a period. Note that if the first monitoring opportunity and the second monitoring opportunity have the same period, the period information may be unified. Note that, by using an offset value to set the second monitoring opportunity, for example, terminals 200 in cell C10 can commonly recognize the second monitoring opportunity.

[0090] (Second Example) In the second example, a first monitoring opportunity and a second monitoring opportunity are set in association with each other. For example, a second monitoring opportunity is set for every M first monitoring opportunities. Alternatively, the start position of the second monitoring opportunity is set, for example, by an offset value. Note that the M monitoring opportunities correspond to, for example, first monitoring opportunities set for each of multiple terminals 200. For example, a second monitoring opportunity is set for every N LOs (N is an integer).

[0091] (Third Example) In the third example, a first monitoring opportunity and a second monitoring opportunity are associated with each other and set. In the third example, numbers (indexes) are assigned to the LOs in ascending order based on a certain criterion, and an index corresponding to each of the first monitoring opportunity and the second monitoring opportunity is set.

[0092] An example of processing when transmitting a second signal within the LO described in the first to third examples above will be described.

[0093] When transmitting a second signal at a second monitoring opportunity according to the second configuration information, the control unit 120 of the base station 100 performs control to set a subgroup identifier in the subgroup field to a specific value (e.g., "1111"). Note that the subgroup field can indicate the corresponding UE depending on the bit position.

[0094] Furthermore, when transmitting a second signal at a second monitoring opportunity according to the second setting information, the control unit 120 of the base station 100 performs control, for example, to set a subgroup identifier in the subgroup field to a value indicating the terminal 200 or terminal group (e.g., "0001"). For example, the first bit of the subgroup field corresponds to the first terminal group, and the second bit of the subgroup field corresponds to the second terminal group. Then, for example, the control unit 120 performs control to activate the first receiving unit 212 only for the terminal group corresponding to the bit assigned with "1".

[0095] Furthermore, when transmitting a second signal at a second monitoring opportunity according to the second setting information, the control unit 120 of the base station 100 controls the transmission of the second signal, for example, without including a subgroup identifier value in the subgroup field.

[0096] Furthermore, when the control unit 220 of the terminal 200 receives a second signal at a second monitoring opportunity according to the second setting information, the control unit 220 may perform control to activate the first receiving unit 212 according to the subgroup identifier included in the subgroup field. Alternatively, when the control unit 220 of the terminal 200 receives a second signal at a second monitoring opportunity according to the second setting information, the control unit 220 performs control to activate the first receiving unit 212, for example, regardless of the information included in the second signal (for example, the value of the subgroup field) (in other words, at the time the second signal is received).

[0097] As described above, in the fourth embodiment, the base station 100 transmits a first signal including first setting information and second setting information to the terminal 200. The base station 100 also transmits a second signal to the terminal 200 at either the first monitoring opportunity corresponding to the first setting information or the second monitoring opportunity corresponding to the second setting information. Then, upon receiving the second signal at either the first monitoring opportunity or the second monitoring opportunity, the terminal 200 activates the first receiving unit 212, which is the main receiver. In this manner, control using LP-WUS can be performed according to the situation. For example, the base station 100 can determine resources for transmitting the second signal according to the terminal 200 that wishes to transmit the third signal, and activate the main receiver of the terminal 200 that wishes to transmit the third signal. Fifth embodiment

[0098] In the first embodiment, an example was described in which the base station 100 transmits a first signal including first setting information and second setting information to the terminal 200, and configures the terminal 200 with a first monitoring opportunity according to the first setting information and a second monitoring opportunity according to the second setting information. In the second embodiment, an example was described in which the terminal 200 transitions from the first state to the second state after receiving a second signal using an entry condition. In the third embodiment, an example was described in which the first monitoring opportunity is associated with a third signal monitoring opportunity, and the second monitoring opportunity is not associated with the third signal monitoring opportunity. In the fourth embodiment, an example was described in which the second signal monitoring opportunity is configured as LO. In the fifth embodiment, an example is described in which the second signal monitoring opportunity is configured as MO. Note that in the fifth embodiment, the wireless communication system, the base station, and the terminal are the same as those in the first embodiment, and therefore description thereof will be omitted.

[0099] In the fifth embodiment, similarly to the third embodiment, the first setting information is information set for each terminal 200 or a group of terminals 200 (hereinafter referred to as a terminal group), and the second setting information is information set for a plurality of terminal groups. Also, the second monitoring opportunity according to the second setting information is not associated with the resource for receiving the third signal.

[0100] In the fifth embodiment, an example will be described in which a first monitoring opportunity and a second monitoring opportunity are set as MOs. Two examples of setting MOs will be described. The settings to be described are set, for example, according to first setting information or second setting information.

[0101] (First Example) The first example is an example in which an MO to be set as the second monitoring opportunity is directly specified.

[0102] The control unit 120 of the base station 100 assigns numbers (indexes) to the MOs in ascending order, for example, and includes index information of the MO corresponding to the second monitoring opportunity in the second configuration information.

[0103] Furthermore, the control unit 120 of the base station 100 may set an MO corresponding to the second monitoring opportunity, for example, by using a bitmap. For example, the second configuration information may include information on the bitmap length corresponding to the number of MOs in the LO. Then, the control unit 220 of the base station 100 sets the second monitoring opportunity by using the bitmap. For example, the control unit 220 sets an MO corresponding to a position indicating "1" in the bitmap as the second monitoring opportunity.

[0104] The MO set as the second monitoring opportunity may belong to the same LO as the MO of the first monitoring opportunity, or may belong to a different LO from the MO of the first monitoring opportunity. If the LO is different from the MO of the first monitoring opportunity, the LO for the second monitoring opportunity can be set by, for example, the method used in the fourth embodiment.

[0105] In this way, it is possible to set an MO corresponding to the second monitoring opportunity.

[0106] (Second Example) In the second example, an MO corresponding to a second monitoring occasion is set using an offset and a period.

[0107] The control unit 120 of the base station 100 includes, in the second configuration information, an offset value for indicating a second monitoring opportunity and information on the period.

[0108] The MO corresponding to the second monitoring opportunity starts from a position indicated by the offset value from the beginning of one or more MOs included in the LO, and the second monitoring opportunity is set for each period. Note that, for example, when only one second monitoring opportunity is set in the LO, the second setting information may include the offset value but not the period information.

[0109] For example, if there are ten MOs, MO #0 to MO #9, in the LO, the offset value is 2, and the period is 4, then there will be three second monitoring opportunities in the LO (MO #2, MO #6, MO #10). Note that although the period is described in an example that includes the second monitoring opportunity, the second monitoring opportunity does not have to be included. Also, the offset value may be replaced with the index number of the MO used in the first example. Therefore, the index value and bitmap in the first example and the offset in the second example may be collectively described as information indicating the second monitoring opportunity.

[0110] The second setting information may also include burst length information. The burst length information is, for example, information indicating the number of consecutive second monitoring operations. In other words, the burst length information can be described as information on the number of consecutive MOs.

[0111] For example, if there are ten MOs (MO#0 to MO#9) in the LO, the offset value is 3, the period is 5, and the burst length is 2, then there will be four second monitoring opportunities in the LO (MO#3, MO#4, MO#8, MO#9). Note that although the period is described as including the second monitoring opportunity, it is not necessary to include the second monitoring opportunity. Also, the offset value may be replaced with the MO index number used in the first example.

[0112] In this way, it is possible to set an MO corresponding to the second monitoring opportunity.

[0113] An example of processing when the second signal is transmitted within the MO described in the first and second examples above will be described.

[0114] When transmitting a second signal at a second monitoring opportunity according to the second setting information, the control unit 120 of the base station 100 includes information indicating a message type in the second signal. The information indicating the message type may be, for example, bitmap information combined with a subgroup field. For example, the first or last bit of the bitmap is set as the bit corresponding to the information indicating the message type. Then, for example, if the bit corresponding to the information indicating the message type is "1," the second signal is determined to have been transmitted at the second monitoring opportunity. Therefore, even if, for example, the MO corresponding to the first monitoring opportunity and the MO corresponding to the second monitoring opportunity are set as the same MO, the terminal 200 can determine which monitoring opportunity the second signal was transmitted at. Therefore, for example, in the fifth process, the terminal 200 can determine whether the condition for transitioning to the second state is the first condition or the second condition.

[0115] In addition to the above, the method described in the fourth embodiment may also be used.

[0116] As described above, in the fifth embodiment, the base station 100 transmits a first signal including first setting information and second setting information to the terminal 200. The base station 100 also transmits a second signal to the terminal 200 at either the first monitoring opportunity corresponding to the first setting information or the second monitoring opportunity corresponding to the second setting information. Then, upon receiving the second signal at either the first monitoring opportunity or the second monitoring opportunity, the terminal 200 activates the first receiving unit 212, which is the main receiver. In this manner, control using LP-WUS can be performed according to the situation. For example, the base station 100 can determine resources for transmitting the second signal according to the terminal 200 that wishes to transmit the third signal, and activate the main receiver of the terminal 200 that wishes to transmit the third signal. Hardware configuration of each device in each embodiment

[0117] The hardware configuration of each device in the wireless communication system of each embodiment will be described with reference to FIGS.

[0118] Fig. 9 is a diagram showing an example of the hardware configuration of base station 100. As shown in Fig. 9, 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. CPU 330 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.

[0119] 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. 9 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, a network IF 360.

[0120] It should be noted that base station 100 may generate a plurality of data signals to be transmitted in a plurality of subbands, and the filters that generate these signals may be configured independently for each subband.

[0121] Fig. 10 is a diagram showing an example of the hardware configuration of terminal 200. As shown in Fig. 10, 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.

[0122] 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. 10 will be described. The transmitter 211, the first receiver 212, and the second receiver 213 (or the communication unit 210) are realized by, for example, an RF circuit 420, or an antenna 410 and an RF circuit 420. The controller 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. Note that the first receiver 212 and the second receiver 213 may use separate antennas 410 and RF circuits 420.

[0123] The embodiments may be combined as appropriate within a range that does not cause any contradiction.

[0124] 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.

[0125] 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.

[0126] 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 Terminal 210 Communication unit 211 Transmitter 212 First receiver 213 Second 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 first receiving unit that receives a first signal including first setting information that sets a first monitoring opportunity for a second signal and second setting information that sets a second monitoring opportunity for the second signal; a second receiving unit that receives the second signal; and a control unit that controls the first receiving unit to monitor the first monitoring opportunity and the second monitoring opportunity, and that controls the first receiving unit to start up in order to receive a third signal when the second signal is detected at the first monitoring opportunity or when the second signal is detected at the second monitoring opportunity.

2. The terminal according to claim 1, wherein the control unit controls the terminal to transition from a first state in which communication is performed using the first receiving unit to a second state in which communication is performed using the second receiving unit depending on the downlink wireless quality after the terminal transitions to an idle state or an inactive state, and the control unit controls the terminal to transition from the second state to the first state when the second receiving unit receives the second signal.

3. The terminal according to claim 2, wherein the control unit controls the terminal to transition from the first state to the second state when, after receiving the third signal, any of the following conditions is met: a predetermined number of monitoring opportunities for the third signal have passed; a predetermined time T has passed since transitioning to the first state; a predetermined number of synchronization signal periods have passed; a signal instructing switching to the second state has been received; and a signal belonging to the signal type notified in the third signal has been received; and the downlink wireless quality exceeds a predetermined threshold.

4. The terminal according to claim 2, wherein the first monitoring occasion corresponds to a third monitoring occasion that is a monitoring occasion for the third signal, and the second monitoring occasion does not correspond to the third monitoring occasion.

5. The terminal according to claim 2, wherein, when the control unit receives the second signal of the first monitoring opportunity, it determines whether to transition from the second state to the first state depending on whether a first condition is satisfied, and when the control unit receives the second signal of the second monitoring opportunity, it determines whether to transition from the second state to the first state depending on whether a second condition different from the first condition is satisfied.

6. The terminal according to claim 1, wherein the first signal is a System Information Block x (SIBx), the second signal is a Low Power Wake Up Signal (LP-WUS), the third signal is a paging Physical Downlink Control Channel (PDCCH), and the second monitoring occasion is an LP-WUS occasion (LO) or an LP-WUS monitoring occasion (MO).

7. The terminal according to claim 6, wherein the second setting information includes information indicating the second monitoring opportunity, and the information indicating the second monitoring opportunity includes information indicating the LO and / or information indicating the MO.

8. The terminal according to claim 6, wherein the second setting information includes information indicating the second monitoring opportunity, and the information indicating the second monitoring opportunity includes information on an offset, a period, and the number of consecutive MOs indicated by the MO.

9. The terminal according to claim 1, wherein the first receiving unit is a main receiver, and the second receiving unit is a wake-up receiver.

10. A base station having: a transmitting unit that transmits a first signal to a terminal, the first signal including first setting information that sets a first monitoring opportunity for a second signal and second setting information that sets a second monitoring opportunity for the second signal; and a control unit that causes the terminal to perform control to receive a third signal by transmitting the second signal using either the first monitoring opportunity or the second monitoring opportunity.

11. A wireless communication system having: a base station that transmits a first signal including first setting information that sets a first monitoring opportunity for a second signal and second setting information that sets a second monitoring opportunity for the second signal; and a terminal having: a first receiving unit that receives the first signal; a second receiving unit that receives the second signal; and a control unit that controls the first receiving unit to start up in order to receive a third signal when the second signal is detected at the first monitoring opportunity or when the second signal is detected at the second monitoring opportunity.

Images