Terminal, base station, and control method

Abstract

The present invention comprises: a first reception circuit; a second reception circuit that operates with low power in comparison to the first reception circuit and receives a wake-up signal for a low power consumption receiver that starts the first reception circuit from a sleep state; and a control circuit that controls the terminal in accordance with control information for controlling the operation of the terminal for a secondary cell, the control information being received by the second reception circuit or the first reception circuit.

Description

Terminal, base station, and control method

[0001] The present disclosure relates to a terminal, a base station, and a control method.

[0002] The 3rd Generation Partnership Project (3GPP) completed the formulation of the New Radio access technology (NR) specifications in Release 15 as the standard for realizing 5th Generation mobile communication systems (5G). Release 15 NR focused on functions that realize high-speed and large-capacity communications, and from Release 16 onwards, studies have been conducted on technologies that achieve high-reliability and low-latency communications, simultaneous connection of multiple terminals, low cost, low power consumption, etc., in order to expand the functionality and expand new scenarios and use cases (see, for example, Non-Patent Document 1).

[0003] 3GPP TS 38.300 V18.2.0, "NR; NR and NG-RAN Overall description; Stage-2 ", June 2024.3GPP TS 38.840 V16.0.0, "NR; Study on User Equipment (UE) power saving in NR ", June 2019.3GPP TS 38.212 V18.2.0, "NR; Multiplexing and channel coding", Feb. 2024.3GPP TR 38.869 V18.0.0, "Study on low-power wake-up signal and receiver for NR ", Dec. 2023.

[0004] There is a demand for further reduction in power consumption of terminals using WUS.

[0005] Non-limiting examples of the present disclosure contribute to providing terminals with lower power consumption.

[0006] A terminal according to one embodiment of the present disclosure includes a first receiving circuit, a second receiving circuit that operates with less power than the first receiving circuit and receives a wake-up signal for a low-power receiver that wakes up the first receiving circuit from a sleep state, and a control circuit that controls the terminal in accordance with control information received by the second receiving circuit or the first receiving circuit for controlling the operation of the terminal with respect to a secondary cell.

[0007] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0008] According to an embodiment of the present disclosure, it is possible to provide a terminal with lower power consumption.

[0009] Further advantages and benefits of one embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features.

[0010] Diagram showing an example of a system configuration incorporating LP-WUR and LP-WUS Diagram showing an example of a monitoring operation procedure Diagram showing an example of a monitoring operation procedure Diagram showing an example of a monitoring operation procedure Diagram showing an example of a monitoring operation procedure Diagram showing an example of a bit sequence according to an overlaid sequence Diagram showing an example of operation between LR and MR Diagram showing an example of operation between LR and MR Block diagram showing an example of the configuration of a part of a terminal Block diagram showing an example of the configuration of a part of a base station Block diagram showing an example of the main configuration of a terminal Block diagram showing the main configuration of a base station Diagram showing an example of a bit sequence according to an overlaid sequence Diagram showing an example of a bit sequence according to an overlaid sequence Diagram of an example architecture of a 3GPP NR system Diagram of an example functional division in 5G O-RAN

[0011] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0012] Discontinuous Reception (DRX) has been defined since LTE (Long Term Evolution) as a technology to reduce power consumption in terminals. Terminals secure sleep time and reduce power consumption by repeating a DRX cycle at regular intervals, which consists of a wake-up period (called "OnDuration" or "DRX active state") in which they monitor signals such as the downlink control signal PDCCH (Physical Control Downlink Channel) and a sleep period (called "OffDuration" or "DRX inactive state") in which monitoring is not necessary.

[0013] The DRX cycle is called the C-DRX (Connected DRX) cycle in RRC CONNECTED mode. In Release 16, Wake Up Signal (WUS) is specified as Downlink Control Information (DCI) format 2_6, assuming this C-DRX cycle operation.

[0014] The WUS is notified to a terminal in the RRC CONNECTED state, and the terminal is instructed to wake up or to skip PDCCH monitoring before the C-DRX active period (this instruction is called a "wake-up indication"). This allows the terminal to know in advance whether PDCCH monitoring is necessary, and by reducing unnecessary wake-ups, power consumption in the RRC CONNECTED state can be reduced (see, for example, Non-Patent Documents 2 and 3).

[0015] [LP-WUR, LP-WUS] In Release 18, a new low-power receiving module called LP-WUR (Low-Power Wake Up Receiver, hereinafter also referred to as "LR") was considered for equipment (hereinafter also referred to as "UE") as a wake-up signal for low-power receivers. LP-WUR monitors control signals generated by a modulation method different from the DCI format transmitted on the PDCCH, such as the Wake-Up Signal (WUS) specified in Release 16. Specifically, LP-WUR monitors the Low-Power Wake-Up Signal (LP-WUS), which is a control signal with a simple waveform such as ON-OFF Keying (OOK). This is considered to reduce the power consumption related to UE wake-up (see Non-Patent Document 4).

[0016] In addition, it is being considered that LP-WUS will at least notify the wake-up of the terminal. The payload size for notifying the wake-up is restricted to simplify the signal generation of LP-WUS and simplify and reduce the power consumption of the reception process of LP-WUR.

[0017] In a terminal in the RRC CONNECTED state equipped with LP-WUR, a conventional NR receiving module (also called Main Radio: MR) in the sleep state is triggered to wake up in response to the notification content of the received LP-WUS, and the woken up MR performs PDCCH monitoring based on the conventional NR signal processing procedure. It is being considered that a terminal equipped with LP-WUR will be able to support carrier aggregation operation in the RRC CONNECTED state, just like a conventional terminal.

[0018] FIG. 1 is a diagram showing an example of a system configuration incorporating LP-WUR and LP-WUS. FIG. 1 shows a terminal 100 and a base station 200. The terminal 100 includes an LR 110, which is a standby / reception-only module, and an MR (Main Radio) 120, which is a main receiver. The LR 110 operates with less power than the MR 120. By including the LR 110, which operates with less power than the MR 120, a terminal with lower power consumption can be provided.

[0019] The LR performs intermittent reception or continuous reception at a fixed cycle regardless of the operating state of the MR (for example, signal standby state or sleep state). In addition to the conventional NR signal, the base station 200 transmits an LP-WUS as a control signal for the LR.

[0020] The terminal 100 demodulates and decodes the received LP-WUS signal at the LR 110. The receiving antenna for the LP-WUS signal may be dedicated to receiving the LP-WUS signal as shown in FIG. 1, or may be the same as the receiving antenna for the NR signal.

[0021] When the terminal 100 is in the RRC CONNECTED state, if the decoding result in the LR includes an instruction to start the MR 120, the terminal 100 starts the MR 120 in response to an instruction from the LR 110 and performs an operation of monitoring the NR signal. In these configurations, the LR 110 performs LP-WUS detection with low power consumption and the MR 120 ensures a sleep time, thereby reducing the power consumption of the terminal 100.

[0022] [PDCCH monitoring operation after LP-WUS detection] The following four procedures have been considered for the LP-WUS monitoring and detection and PDCCH monitoring operation in a terminal. Figures 2 to 5 are diagrams showing examples of monitoring operation procedures.

[0023] 2 to 5 show the operation of the LR and MR in chronological order. The terminal monitors the LP-WUS during the LP-WUS monitoring interval (Monitoring Occasion: MO), which is repeated at regular intervals. When the LR detects an instruction to activate the MR, the terminal activates the MR and monitors the PDCCH.

[0024] In the first monitoring operation procedure shown in Fig. 2, the terminal starts the on-duration (active time) of the C-DRX cycle operation using the LP-WUS as a trigger, and monitors the PDCCH during that period. This operation is the same as when the terminal receives the existing DCI 2_6.

[0025] In the second monitoring operation procedure shown in Figure 3, the terminal starts an additional On-duration interval triggered by an LP-WUS received outside the On-duration interval of C-DRX, and monitors an additional PDCCH within that interval.

[0026] In the third monitoring operation procedure shown in FIG. 4, the terminal monitors the PDCCH within the On-duration interval of C-DRX, triggered by an LP-WUS received within that On-duration interval.

[0027] In the fourth monitoring operation procedure shown in Figure 5, the terminal starts the On-duration section and monitors the PDCCH only when there is an MR activation instruction from the base station by an LP-WUS notification independent of the C-DRX cycle.

[0028] [SCell dormancy indication] Release 16 specifies the dormancy state of a secondary cell (SCell) as a power consumption reduction technique for terminals supporting Carrier Aggregation (CA) in the RRC CONNECTED state. For dormant secondary cells or secondary cell groups, the terminal stops PDCCH monitoring and performs only radio resource measurements. This reduces terminal power consumption.

[0029] A dormant cell or cell group is notified to a terminal as an SCell dormancy indication together with a wake-up indication by DCI format 2_6 (WUS) outside the C-DRX active period. The SCell dormancy indication is notified in bitmap format and is described as having a maximum of 5 bits. Within the C-DRX active period, it is also notified by DCI format 0_1, 0_3 or DCI format 1_1, 1_3, and the maximum number of bits is 5, the same as when it is included in DCI format 2_6 (see, for example, Non-Patent Documents 2 and 3).

[0030] [Payload size of DCI 2_6 (WUS) and LP-WUS] For each UE, the payload size of DCI 2_6 is a maximum of 6 bits, and its configuration is specified as follows (see Non-Patent Document 3). The same maximum number of bits is reserved for the SCell dormancy indication in other DCI formats. - Wake-up indication: 1 bit - SCell dormancy indication: Maximum 5 bits (bitmap format)

[0031] On the other hand, the payload size of LP-WUS for a terminal in the RRC CONNECTED state is being considered to be a maximum of 8 or 16 bits. The payload configuration is being considered to include at least a wake-up indication for each UE or UE group. Bit allocation methods are being considered, including a bitmap format or a codepoint format for each UE or UE group. In other words, like the existing DCI 2_6 (WUS), a base station can use LP-WUS to transmit control information other than a wake-up indication to a terminal.

[0032] [Overlaid Sequence in OOK System] The OOK system is being considered as the transmission signal waveform for LP-WUS. LP-WUR systems are being considered that can demodulate and decode OOK signals and those that can decode overlaid sequences. To transmit LP-WUS that can be decoded, the base station transmits a bit sequence using the overlaid sequence in OOK. The terminal's LP-WUR demodulates and decodes the OOK signal or the overlaid sequence depending on the corresponding demodulation / decoding system.

[0033] 6 is a diagram showing an example of a bit string based on an overlaid sequence, in which "00100110" is used as an example of a wake-up signal.

[0034] As shown in Figure 6, the base station generates LP-WUS using the OOK method by corresponding the transmission bit sequence to the ON / OFF of the transmission power of each OFDM symbol. In other words, the transmission bits are modulated in the time direction of the OFDM symbols. Each bit in the transmission bit sequence is modulated using a fixed ON / OFF pattern that corresponds to either 0 or 1 for that bit. The terminal detects this ON / OFF pattern from the time waveform of the received signal (envelope detection) and decodes the received bit sequence "00100110."

[0035] On the other hand, a method is also being considered in which a terminal detects a pseudo-random or binary sequence superimposed in the frequency domain during the OOK ON time to receive LP-WUS. When transmitting LP-WUS using an overlaid sequence, the base station assigns a unique sequence corresponding to the transmission bit pattern in the frequency domain. The transmission bits corresponding to one sequence may be two bits as shown in Figure 6, or three or more bits.

[0036] With this scheme, a terminal can receive a bit sequence of the same length as a sequence transmitted using the OOK scheme with fewer symbols. For example, in the case of Figure 6, when "0010" is received in the OOK sequence, "00100110" can be received in the overlaid sequence. The base station can also allocate and transmit additional information in unused frequency regions.

[0037] First Embodiment This embodiment has been considered with a focus on the following characteristics: [PDCCH monitoring operation after LP-WUS detection, LP-WUS payload size, and overlaid sequence]

[0038] As mentioned above, reducing terminal power consumption can be achieved by reducing unnecessary NR signal transmission and reception opportunities and ensuring MR sleep time. In LP-WUS, it is being considered to enable the LP-WUS function to support carrier aggregation in the RRC CONNECTED state.

[0039] On the other hand, carrier aggregation is a method that enables communication between a primary cell and one or more secondary cells. Therefore, when using multiple cells, there is a concern that the power consumption of the terminal, especially the MR, will increase.

[0040] Therefore, if a terminal can grasp in advance control information for controlling the terminal's operation with respect to secondary cells, such as information about secondary cells that do not require monitoring of NR control signals (hereinafter referred to as "control information regarding secondary cells" or simply "control information"), it is thought that unnecessary MR operations can be reduced, leading to a reduction in the terminal's power consumption.

[0041] Release 16 specifies control information related to secondary cells, such as SCell dormancy indication. However, it does not specify notification of control information related to secondary cells other than SCell dormancy indication to terminals. Furthermore, when LP-WUS is introduced, it is not clear how terminals acquire control information related to secondary cells.

[0042] In LP-WUS, a procedure is being considered in which a terminal in the RRC CONNECTED state monitors the PDCCH when triggered by a wake-up instruction from the LP-WUS to the MR. In other words, the MR can remain in sleep mode until it is woken up by the detection result of the LP-WUS, allowing the terminal to maintain low power consumption.

[0043] 7 is a diagram showing an example of the operation of the LR and the MR when the MR receives control information related to a secondary cell after being activated by the LP-WUS. In FIG. 7, the MR is first activated using the LP-WUS as a trigger. Then, the control information related to the secondary cell is received by the PDCCH of the MR. In this case, as shown in FIG. 7, the time required from the activation of the MR to the operation corresponding to the control information related to the secondary cell increases, and the responsiveness of the terminal decreases.

[0044] 8 is a diagram showing an example of the operation of the LR and the MR when control information related to a secondary cell is received before activation of the MR by the LP-WUS. In FIG. 8, the LR receives control information related to the secondary cell together with a wake-up indication before activating the MR, and activates the MR. At the time of activation, the MR acquires the control information related to the secondary cell. This allows the MR to maintain a low power consumption state while improving responsiveness until carrier aggregation operation after MR activation.

[0045] In LP-WUS, the maximum payload size of the LP-WUS for a terminal is currently considered to be 8 bits or 16 bits. Because of this relatively small size, there are limitations to the simultaneous transmission of various information, such as when the LP-WUS notifies the terminal of control information related to a secondary cell along with a wake-up indication. Therefore, by using the overlay sequence transmission method described above, it is possible to transmit a large amount of control information to the terminal within the limited resources occupied by the LP-WUS.

[0046] [Configuration of Base Station and Terminal] Fig. 9 is a block diagram showing a partial configuration example of a terminal 100 according to one embodiment of the present disclosure. In the terminal 100 shown in Fig. 9, a receiver (e.g., corresponding to a second receiver circuit or a first receiver circuit) receives an LP-WUS and wakes up from a sleep state in response to the reception of the LP-WUS, and a controller (e.g., corresponding to a control circuit) controls the terminal 100 in response to control information received by the receiver for controlling the operation of the terminal 100 with respect to the secondary cell. Fig. 10 is a block diagram showing a partial configuration example of a base station 200 according to one embodiment of the present disclosure. In the base station 200 shown in Fig. 10, a controller (e.g., corresponding to a control circuit) generates control information for controlling the operation of the terminal with respect to the secondary cell, and a transmitter (e.g., corresponding to a transmission circuit) transmits the LP-WUS and the control information to the terminal.

[0047] [Block diagram of terminal 100] Fig. 11 is a block diagram showing an example of the main configuration of the terminal 100 according to this embodiment. As described in Fig. 1, the terminal 100 includes an LR 110 that performs reception processing of LP-WUS and an MR 120 that performs transmission and reception processing of conventional NR signals.

[0048] The LR 110 is composed of an LP-WUS receiving unit 111, an LP-WUS detecting unit 112, and a control information holding unit 113. The LP-WUS receiving unit 111 of the LR receives an LP-WUS via the antenna 101 and outputs a signal that has been subjected to receiving processes such as down-conversion and A / D conversion to the LP-WUS detecting unit 112.

[0049] The LP-WUS detection unit 112 demodulates the signal output by the LP-WUS reception unit 111 and detects control information, obtains a start-up instruction for the MR 120 and control information related to the secondary cell, and outputs the information to the control information holding unit 113.

[0050] The MR 120 is composed of an MR receiving unit 121 , a demodulating and decoding unit 122 , a control information holding unit 123 , a receiving control unit 124 , a transmission control unit 125 , a transmission signal generating unit 126 , an encoding and modulation unit 127 , and an MR transmitting unit 128 .

[0051] The MR receiving unit 121 performs receiving processes such as down-conversion and A / D conversion on the signal received via the antenna 101 and outputs the signal to the demodulation and decoding unit 122. The demodulation and decoding unit 122 demodulates and decodes the received signal input from the MR receiving unit 121 to obtain DL data 129 or control information. The control information is output from the demodulation and decoding unit 122 to a control information holding unit 123.

[0052] The reception control unit 124 activates and controls the reception function based on the control information output from the control information storage unit 113 of the LR 110. The reception control unit 124 issues instructions to activate and control signal reception of the MR reception unit 121 based on, for example, activation and control information from the LR.

[0053] The transmission control unit 125 activates and controls the transmission function based on the control information output from the control information storage unit 113 of the LR 110. For example, based on an activation / control instruction from the LR 110, the transmission control unit 125 issues activation / transmission signal generation instructions to the transmission signal generation unit 126 and outputs data to be transmitted.

[0054] The transmission signal generation unit 126 generates transmission data based on the data and control information generation instructions input from the transmission control unit 125, and outputs the generated transmission data to the coding and modulation unit 127. The coding and modulation unit 127 codes and modulates the transmission data input from the transmission signal generation unit 126, and outputs the transmission signal to the MR transmission unit 128.

[0055] The MR transmission unit 128 performs transmission processing such as D / A conversion, up-conversion, and amplification on the signal input from the encoding / modulation unit 127, and transmits the radio signal obtained by the transmission processing from the antenna 101 to the terminal 100.

[0056] 12 is a block diagram showing the main components of the base station 200 according to this embodiment. The base station 200 is made up of an antenna 201, a base station receiving unit 202, a demodulation and decoding unit 203, a scheduling unit 205, a control information holding unit 206, a data and control information generating unit 208, an encoding and modulation unit 209, an LP-WUS signal generating unit 210, an LP-WUS modulation unit 211, and a base station transmitting unit 212.

[0057] The base station receiving unit 202 performs reception processing such as down-conversion and A / D conversion on the received signal received via the antenna 201 and outputs the resulting signal to the demodulation and decoding unit 203. The demodulation and decoding unit 203 demodulates and decodes the received signal input from the base station receiving unit 202, and outputs control information such as a scheduling request transmitted from the terminal 100 from the decoded results to the scheduling unit 205. The demodulation and decoding unit 203 also outputs demodulated and coded DL data 207.

[0058] The scheduling section 205 determines LP-WUS setting information for the terminal 100, such as report information on the capabilities of the terminal 100 (e.g., whether or not the terminal 100 in the cell is equipped with an LR), carrier aggregation capability, etc., the presence or absence of DL data 207 for the terminal 100, a terminal 100 startup instruction, control information related to the secondary cell, etc., and outputs this information to the control information holding section 206. The scheduling section 205 also outputs the scheduling information to the coding and modulation section 209. The scheduling section 205 also outputs the LP-WUS setting information to the LP-WUS modulation section 211. The scheduling section 205 also outputs signaling information related to the allocation of the LP-WUS to the LP-WUS modulation section 211.

[0059] The data and control information generating section 208 generates data and control information for the MR based on the data and control information generation instruction input from the scheduling section 205 and DL data 207, and outputs this to the coding and modulation section 209. The data and control information generating section 208 also arranges data based on the signaling information input from the scheduling section 205, and outputs this to the coding and modulation section 209.

[0060] The encoding / modulation unit 209 outputs to the base station transmission unit 212 a transmission signal that is generated by encoding and modulating the data and control information input from the data and control information generation unit 208 based on the scheduling information input from the scheduling unit 205.

[0061] On the other hand, the LP-WUS signal generation unit 210 generates an LP-WUS signal sequence based on information from higher layers and LP-WUS setting information input from the scheduling unit 205, and outputs it to the LP-WUS modulation unit 211. The LP-WUS modulation unit 211 modulates and allocates the LP-WUS signal sequence based on signaling information related to LP-WUS allocation input from the scheduling unit 205, and outputs it to the base station transmission unit 212.

[0062] The base station transmission unit 212 performs transmission processing such as D / A conversion, up-conversion, and amplification on the signal for MR120 and the LP-WUS for LR110 input from the encoding / modulation unit 209, and transmits the radio signal obtained by the transmission processing from the antenna to the terminal 100.

[0063] [Control information related to secondary cells] The following information A to E that terminal 100 having the above configuration receives via LP-WUS will be described. A: SCell dormancy indication Terminal 100 receives SCell dormancy indication via LP-WUS and is notified of information on dormant cells or cell groups. Terminal 100 stops PDCCH monitoring by MR for the cells or cell groups included in the notification and performs periodic radio resource measurement.

[0064] B: The secondary cell or secondary cell group from which the next PDCCH or PDSCH that the terminal 100 must monitor or buffer is transmitted, and the duration of that monitoring or buffering. The terminal 100 is instructed by the LP-WUS to buffer the PDSCH of the secondary cell or secondary cell group. The terminal 100 is notified by the LP-WUS of the minimum time from receiving the monitoring or buffering instruction until buffering of the PDSCH begins. If the minimum time until monitoring or buffering is longer than the time specified for the terminal 100, the terminal 100 enters a sleep state until monitoring or buffering begins. The terminal 100 is specified by the LP-WUS not the secondary cell or secondary cell group, but a BWP (Band Width Part) within that cell or cell group.

[0065] C: Necessity of PUSCH transmission preparation Terminal 100 is instructed by LP-WUS to prepare for PUSCH transmission in a secondary cell or secondary cell group specified by the base station. Terminal 100 is notified by LP-WUS of the minimum time from receiving the PUSCH transmission preparation instruction until starting PUSCH transmission preparation. Terminal 100 is notified of the minimum time until starting PUSCH transmission preparation. If the minimum time is longer than the time specified for terminal 100, terminal 100 enters a sleep state until starting PUSCH transmission preparation. Terminal 100 is specified by LP-WUS not a secondary cell or secondary cell group, but a BWP (Band Width Part) within that cell or cell group.

[0066] D: Time offset from startup of MR receiver 121 to PDCCH monitoring Terminal 100 is notified of the time offset until PDCCH monitoring by LP-WUS. Terminal 100 enters a sleep state according to the offset until PDCCH monitoring starts if the time is longer than the time specified for terminal 100.

[0067] E: Necessity of L1 measurement or L3 measurement in a secondary cell or secondary cell groupThe terminal 100 is requested to perform both or either L1 measurement and L3 measurement by LP-WUS. The terminal 100 that is requested to perform L1 measurement transmits an SRS (Sounding Reference Signal) for uplink channel quality measurement at the base station 200, and measures CSI-RS for downlink channel quality estimation. The terminal 100 that is requested to perform L3 measurement prepares to transmit an RRC measurement report, and transmits it to the base station 200 when an event occurs.

[0068] One or more of the above information A to E are generated for each terminal 100 according to the scheduling for that terminal 100, and are transmitted together with a wake-up indication from the base station transmitter 212 by LP-WUS. The terminal 100 decodes this information through processing in the LR 110, and based on the instructions, starts up the MR 120 and controls its operation after startup. This operation allows the terminal 100 to reduce unnecessary operations in the secondary cell while reducing response delay, thereby reducing power consumption.

[0069] [Transmission of control information using overlaid sequence] If the terminal 100 is capable of demodulating and decoding the overlaid sequence, the base station 200 may generate an LP-WUS in the encoding / modulation unit 209 by mapping the control information related to the secondary cell to be transmitted to an overlaid sequence of OFDM symbols, i.e., the frequency domain.

[0070] As explained in Figure 6, when an overlaid sequence is applied, when "0010" is received in the OOK sequence, "00100110" can be received in the overlaid sequence. Therefore, in the example of Figure 6, the overlaid sequence can carry additional information in the remaining four symbols of the OOK sequence. In this way, applying an overlaid sequence to the LP-WUS creates free space in the allocated resources of the LP-WUS.

[0071] Therefore, the base station 200 maps the control information for the secondary cell to the OFDM symbols following the wake-up indication. In this mapping, a sequence for the terminal 100 to determine whether demodulation and decoding operations for the symbols following the wake-up indication are necessary is mapped to the frequency domain. When using the subsequent symbols in this manner, the terminal 100 needs to determine whether information exists after the wake-up indication in order to reduce unnecessary demodulation and decoding operations. In this embodiment, two types of patterns are proposed to notify whether information exists after the wake-up indication.

[0072] Figures 13 and 14 are diagrams showing examples of bit sequences using overlaid sequences. Figure 13 is a diagram for explaining the first pattern, and Figure 14 is a diagram for explaining the second pattern. The difference between Figures 13 and 14 is the first OFDM symbol of the LP-WUS occupied resource. As with Figure 6, "00100110" is used as the wake-up signal.

[0073] The first OFDM symbol shown in Figure 13 is a symbol in which a sequence indicating the presence of subsequent data (a waveform depicted by a dashed line in the figure) is superimposed on the first "00" sequence of the wake-up signal. By searching the first OFDM symbol for a sequence indicating the presence of subsequent data, terminal 100 can determine whether or not information exists after the wake-up signal. In addition, control information related to the secondary cell can be allocated to the empty space (the fifth to eighth symbols) obtained by applying the overlaid sequence to the LP-WUS.

[0074] The first OFDM symbol shown in Figure 14 is a symbol that notifies an overlaid sequence that indicates only whether or not information exists after the wake-up signal. In this case, the wake-up signal "00100110" is notified from the second symbol. In addition, control information related to the secondary cell can be allocated to the free space (the sixth to eighth symbols) obtained by applying the overlaid sequence to the LP-WUS.

[0075] In either of the two patterns, the terminal 100 identifies the sequence by the correlation between the sequence allocated in the frequency direction of the received signal and the known sequence in the demodulation and decoding unit 122. If the terminal 100 determines, as a result of demodulating and decoding the first symbol, that control information related to the secondary cell is included after the wake-up signal, it demodulates and decodes not only the symbol corresponding to the wake-up indication but also the subsequent symbols. In this way, by using the free space, it is possible to effectively use LP-WUS resources.

[0076] This allows the base station to effectively utilize allocated resources and notify terminals 100 capable of demodulating and decoding the overlaid sequence of control information related to the secondary cell. By being notified of the presence or absence of the control information, terminals 100 can reduce unnecessary demodulation and decoding processes, leading to reduced power consumption. Furthermore, if it is possible to allocate all the necessary control information to the free space, transmission using the DCI format becomes unnecessary.

[0077] The first OFDM symbol may indicate not only whether or not there is information after the wake-up signal, but also the number of allocated OFDM symbols if there is information.

[0078] Second Embodiment This embodiment is an embodiment that has been considered with a focus on the following characteristics. [PDCCH Monitoring Operation After LP-WUS Detection, and LP-WUS Payload Size] When all control information related to a secondary cell is notified to terminal 100 by LP-WUS together with an MR activation instruction, it is expected that the more types of control information there are, the more the LP-WUS payload will be occupied. Therefore, this embodiment describes a mode in which base station 200 transmits part of the control information related to the secondary cell by LP-WUS, and transmits the remaining control information by PDCCH after MR activation. Note that the control information related to the secondary cell in the second embodiment is the same information as the control information related to the secondary cell in the first embodiment.

[0079] [Configuration of base station 200] The block diagram of base station 200 is the same as that of the first embodiment, but some functions are different. Scheduling section 205 distributes control information related to secondary cells for each terminal 100 into information to be transmitted via LP-WUS and information to be transmitted via PDCCH. LP-WUS signal generation section 210 or data / control information generation section 208 transmits control information based on information from higher layers, in accordance with the scheduling.

[0080] [Configuration of Terminal 100] The block diagram of the terminal 100 is the same as that of the first embodiment, but some functions are different. The LP-WUS receiving unit 111 receives the LP-WUS, and the LP-WUS detecting unit 112 decodes the MR activation instruction and control information related to the secondary cell. The decoded information is output to the control information holding unit 113, and based on the control information, the reception control unit 124 or the transmission control unit 125 of the MR 120 controls the operation of the MR 120. The MR receiving unit 121 receives the PDCCH, and the demodulation / decoding unit 122 decodes the control signal and outputs it to the control information holding unit 123. The control information holding unit 123 outputs the input control information to the reception control unit 124 or the transmission control unit 125 depending on the information. The reception control unit 124 or the transmission control unit 125 performs reception or transmission operation by the MR 120 based on the received control information.

[0081] [Reception of control information via LP-WUS and PDCCH] A method for receiving control information related to a secondary cell will be described. The terminal 100 receives control information via both the LP-WUS and PDCCH in response to a requested operation immediately after activating the MR 120. That is, the terminal 100 receives some control information indicating control immediately after activating the MR 120 together with a wake-up indication via the LP-WUS. Of the control information, the remaining control information is received via the PDCCH after activating the MR 120 or at the next transmission timing.

[0082] In this operation, which control information is to be received by which control signal is set in advance in the terminal 100. Examples of the setting method include setting by RRC and setting by notification of information included in the subsequent PDCCH by LP-WUS. The following two examples are examples of an operation in which the terminal 100 is notified of control information related to the secondary cell by both LP-WUS and PDCCH.

[0083] (Operation Example 1) When terminal 100 is requested to perform L1 measurement or L3 measurement in a secondary cell immediately after activating MR 120, terminal 100 receives the request for L1 or L3 measurement via LP-WUS during sleep of MR 120. After activating MR 120, terminal 100 performs an operation based on an instruction from LP-WUS and then receives the remaining control information via PDCCH.

[0084] (Operation Example 2) When terminal 100 is requested to perform CSI measurement in a secondary cell immediately after activating MR 120, terminal 100 receives control information related to CSI measurement, for example, a CSI-RS measurement or an SRS transmission request, via LP-WUS. After receiving the LP-WUS, terminal 100 performs CSI measurement after activating MR 120, and then receives the remaining control information via PDCCH.

[0085] As described above, in this embodiment, the terminal 100 first receives the LP-WUS when the MR 120 is in the sleep state, and obtains a start-up instruction for the MR 120 and control information related to the secondary cell immediately after start-up in the demodulation and decoding unit 122 of the LR 110. In response to this control information, the terminal 100 performs an operation related to the secondary cell requested by the base station 200 in the MR 120.

[0086] That is, the LR 110 receives, together with the LP-WUS, immediate control information from the control information, which indicates the control to be performed immediately after the MR receiving unit 121 is started up in response to receiving the LP-WUS, and the MR 120 receives, after starting up from a sleep state in response to receiving the LP-WUS, information from the control information other than the immediate control information.

[0087] This reduces the response delay of the terminal 100 from the start-up of the MR 120 to the operation related to the secondary cell, and also reduces the power consumption of the terminal 100 related to the reception of control information.

[0088] <Third Embodiment> This embodiment is an embodiment that has been considered with a focus on the following characteristics. [PDCCH Monitoring Operation After LP-WUS Detection, and LP-WUS Payload Size] Since the payload size of the LP-WUS is limited, it has also been considered to limit the information transmitted by the LP-WUS to a minimum. In this case, it is assumed that the terminal 100 receives only an activation instruction for the MR 120 by the LP-WUS. Therefore, in this embodiment, an embodiment in which only an activation instruction for the MR 120 is received by the LP-WUS will be described. Note that the control information related to the secondary cell in the third embodiment is the same information as the control information related to the secondary cell in the first embodiment.

[0089] [Configuration of base station 200] The block diagram of base station 200 is the same as that of the first embodiment, but some functions are different. A scheduling unit 205 determines a wake-up instruction for each terminal 100 and control information related to the secondary cell. Based on the wake-up instruction for each terminal 100, an LP-WUS signal generation unit 210 generates an LP-WUS signal sequence, an LP-WUS modulation unit 211 generates a modulated signal, and the modulated signal is transmitted from a base station transmission unit 212. Control information related to the secondary cell is generated in a data and control information indication unit based on scheduling, and is coded and modulated before being transmitted as a PDCCH.

[0090] [Configuration of Terminal 100] The block diagram of the terminal 100 is the same as that of the first embodiment, but some functions are different. The LP-WUS receiver 111 receives the LP-WUS, and the LP-WUS detector 112 outputs a terminal startup instruction. The control information holder 113 of the LR 110 outputs the terminal startup instruction to the reception controller 124. Upon receiving the terminal startup instruction, the reception controller 124 of the MR 120 starts up the MR receiver 121 and receives the PDCCH. The demodulator / decoder 122 decodes the PDCCH and outputs control information related to the secondary cell to the control information holder 123. The control information holder 123 outputs the control information to the reception controller 124 or the transmission controller 125, and controls the next operation of the MR 120.

[0091] [Transmission of control information related to secondary cells via PDCCH] Base station 200 transmits an LP-WUS including only a wake-up indication. After that, all control information related to secondary cells is notified to terminal 100 by DCI (Downlink Control Information) transmitted via the PDCCH.

[0092] The terminal 100 first receives the LP-WUS when the MR 120 is in the sleep state, and the demodulation and decoding unit 122 of the LR 110 acquires an instruction to start the MR 120. Based on the instruction, the MR 120 starts up and monitors the PDCCH, and the terminal 100 acquires control information related to the secondary cell.

[0093] That is, the LR 110 does not receive control information, and the MR 120 wakes up from a sleep state in response to receiving the LP-WUS, and then receives control information for controlling the operation of the terminal 100 for the secondary cell.

[0094] In this way, it is possible to notify terminal 100 of control information related to the secondary cell without occupying the limited payload of the LP-WUS, and to reduce the power consumption of terminal 100.

[0095] Note that the PDCCH in this embodiment may be DCI format 2_6 or another DCI format. Terminal 100 may be notified of control information related to secondary cells using DCI format 0_1, 0_2, or 0_3 for transmitting UL schedule information or DCI format 1_1, 1_2, or 1_3 for transmitting DL schedule information. Notification of control information related to secondary cells in a DCI format may be notified to terminal 100 in advance by RRC or higher layer signaling.

[0096] In the embodiment described above, the terminal 100 has a configuration in which the LR 110 and the MR 120 are separated into two parts. However, the functions of the LR 110 may be provided inside the MR 120 of the terminal 100, and the MR 120 may receive the LP-WUS.

[0097] Furthermore, the term "LP-WUS" used in the embodiments may be called "low power control information," "low power indication," or some other name.

[0098] In the above embodiment, the base station transmits the LP-WUS, but the LP-WUS may be transmitted by a terminal other than the base station, or by a transmitting device separate from the base station or terminal.

[0099] In the above embodiments, a downstream control signal is used for explanation, but each embodiment may be applied to an upstream control signal.

[0100] (Supplementary Note) Information indicating whether the terminal supports the functions, operations, or processes described in each of the above-described embodiments and each supplementary note may be transmitted (or notified) from the terminal to the base station 100, for example, as capability information or capability parameters of the terminal.

[0101] The capability information may include an information element (IE) that individually indicates whether the terminal supports at least one of the functions, operations, or processes described in the above-described embodiments, modifications, and supplements. Alternatively, the capability information may include an information element that indicates whether the terminal supports a combination of any two or more of the functions, operations, or processes described in the above-described embodiments, modifications, and supplements.

[0102] For example, the base station 100 may determine (or decide or assume) the functions, operations, or processes that the terminal that transmitted the capability information supports (or does not support) based on the capability information received from the terminal. The base station 100 may perform operations, processes, or control according to the determination result based on the capability information. For example, the base station 100 may include a control circuit that generates control information for controlling the operation of the terminal with respect to the secondary cell based on the capability information received from the terminal, and may transmit a wake-up signal for a low-power receiver and the control information to the terminal.

[0103] Note that the fact that a terminal does not support some of the functions, operations, or processes described in the above-described embodiments, modifications, and supplementary notes may be interpreted as meaning that such some of the functions, operations, or processes are restricted in the terminal. For example, information or a request regarding such restrictions may be notified to the base station 100.

[0104] Information regarding the capabilities or limitations of the terminal may, for example, be defined in a standard, or may be implicitly notified to the base station 100 in association with information known at the base station 100 or information transmitted to the base station 100.

[0105] (Control Signal) In the present disclosure, a downlink control signal (or downlink control information) related to an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a Physical Downlink Control Channel (PDCCH) of a physical layer, or a signal (or information) transmitted in a Medium Access Control Control Element (MAC CE) or Radio Resource Control (RRC) of a higher layer. Furthermore, the signal (or information) is not limited to being notified by a downlink control signal, but may be predefined in a specification (or standard) or preconfigured in a base station and a terminal.

[0106] In the present disclosure, an uplink control signal (or uplink control information) related to an embodiment of the present disclosure may be, for example, a signal (or information) transmitted in a PUCCH of a physical layer, or a signal (or information) transmitted in a MAC CE or RRC of a higher layer. Furthermore, the signal (or information) is not limited to being notified by an uplink control signal, but may be predefined in a specification (or standard) or preconfigured in a base station and a terminal. Furthermore, the uplink control signal may be replaced with, for example, uplink control information (UCI), 1st stage sidelink control information (SCI), or 2nd stage SCI.

[0107] (Base Station) In one embodiment of the present disclosure, the base station may be a Transmission Reception Point (TRP), a cluster head, an access point, a Remote Radio Head (RRH), an eNodeB (eNB), a gNodeB (gNB), a Base Station (BS), a Base Transceiver Station (BTS), a parent device, a gateway, or the like. In sidelink communication, a terminal may play the role of a base station. Instead of a base station, a relay device that relays communication between an upper node and a terminal may be used. Alternatively, a roadside unit may be used.

[0108] (Uplink / Downlink / Sidelink) An embodiment of the present disclosure may be applied to, for example, any of the uplink, downlink, and sidelink. For example, an embodiment of the present disclosure may be applied to a Physical Uplink Shared Channel (PUSCH), a Physical Uplink Control Channel (PUCCH), or a Physical Random Access Channel (PRACH) in the uplink, a Physical Downlink Shared Channel (PDSCH), a PDCCH, or a Physical Broadcast Channel (PBCH) in the downlink, or a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Control Channel (PSCCH), or a Physical Sidelink Broadcast Channel (PSBCH) in the sidelink.

[0109] The PDCCH, PDSCH, PUSCH, and PUCCH are examples of a downlink control channel, a downlink data channel, an uplink data channel, and an uplink control channel, respectively. The PSCCH and PSSCH are examples of a sidelink control channel and a sidelink data channel. The PBCH and PSBCH are examples of a broadcast channel, and the PRACH is an example of a random access channel.

[0110] (Data Channel / Control Channel) An embodiment of the present disclosure may be applied to, for example, either a data channel or a control channel. For example, the channel in an embodiment of the present disclosure may be replaced with any of the data channels PDSCH, PUSCH, and PSSCH, or the control channels PDCCH, PUCCH, PBCH, PSCCH, and PSBCH.

[0111] (Reference Signal) In one embodiment of the present disclosure, the reference signal is, for example, a signal known by both the base station and the mobile station, and may also be called a Reference Signal (RS) or a pilot signal. The reference signal may be any of a Demodulation Reference Signal (DMRS), a Channel State Information - Reference Signal (CSI-RS), a Tracking Reference Signal (TRS), a Phase Tracking Reference Signal (PTRS), a Cell-specific Reference Signal (CRS), or a Sounding Reference Signal (SRS).

[0112] (Time Interval) In one embodiment of the present disclosure, the unit of time resource is not limited to one or a combination of slots and symbols, but may be, for example, a time resource unit such as a frame, a superframe, a subframe, a slot, a time slot, a subslot, a minislot, a symbol, an Orthogonal Frequency Division Multiplexing (OFDM) symbol, or a Single Carrier-Frequency Division Multiplexing Access (SC-FDMA) symbol, or another time resource unit. Furthermore, the number of symbols included in one slot is not limited to the number of symbols exemplified in the above-mentioned embodiment, and may be another number of symbols.

[0113] (Frequency Band) An embodiment of the present disclosure may be applied to either a licensed band or an unlicensed band.

[0114] (Communication) An embodiment of the present disclosure may be applied to communication between a base station and a terminal (Uu link communication), communication between terminals (Sidelink communication), Vehicle to Everything (V2X) communication, or communication between an Ambient IoT Reader and an Ambient IoT Device. For example, the channel in an embodiment of the present disclosure may be replaced with any of PSCCH, PSSCH, Physical Sidelink Feedback Channel (PSFCH), PSBCH, PRDCH (Physical Reader-to-Device Channel), PDRCH (Physical Device-to-Reader Channel), PDCCH, PUCCH, PDSCH, PUSCH, or PBCH. For example, the control information in an embodiment of the present disclosure may be replaced with any of DCI, UCI, SCI (Sidelink Control Information), R2D Control Information, and D2R Control Information. For example, the terminal and base station in an embodiment of the present disclosure may be replaced with an Ambient IoT Device or an Ambient IoT Reader.

[0115] The Ambient IoT Device may be a wireless communication device with a backscattering function or a transmission / reception bandwidth of several resource blocks or less. The Ambient IoT Reader may be a wireless communication device with a communication function with the Ambient IoT Device. The Ambient IoT Device may also be called an Ambient IoT terminal, IoT terminal, LPWA terminal, or tag.

[0116] An embodiment of the present disclosure may be applied to a terrestrial network, a non-terrestrial network (NTN) using a satellite or a high altitude pseudo satellite (HAPS), or a terrestrial network in which transmission delay is large compared to the symbol length or slot length, such as a network with a large cell size or an ultra-wideband transmission network.

[0117] (SBFD) In ​​one embodiment of the present disclosure, operations on uplink, downlink, and sidelink symbols may be applied to symbols (e.g., SBFD symbols) on which SBFD (Subband Non-Overlapping Full Duplex, Subband Full Duplex) operations or controls are performed. In SBFD symbols, a frequency domain (or frequency resource, frequency band) is divided into multiple frequency domains (e.g., subbands, RB sets, subbands, or sub-BWPs (Bandwidth Parts)). A terminal transmits and receives in different directions (e.g., downlink or uplink) in units of subbands, which are the divided domains. In SBFD symbols, a terminal may transmit and receive in one direction, either uplink or downlink, but not in the other direction. On the other hand, a base station may be capable of transmitting and receiving on both the uplink and downlink simultaneously. SBFD symbols may have a smaller frequency domain available for downlink use than symbols that transmit and receive only downlink use. Also, SBFD symbols may have a smaller frequency domain available for uplink use than symbols that transmit and receive only uplink use.

[0118] In addition, in the SBFD symbol, a terminal may transmit and receive uplink and downlink simultaneously. In this case, the frequency domain in which the terminal transmits and the frequency domain in which the terminal receives may not be adjacent, but may be separated by a frequency interval (also called a frequency gap).

[0119] In addition, different transmission and reception directions in subband units, which are divided areas, may include transmission and reception of side links.

[0120] (XDD: Cross Division Duplex) In one embodiment of the present disclosure, the operation for uplink, downlink, and sidelink symbols may be applied to symbols (e.g., full duplex symbols) where full duplex operation or control is performed. In a full duplex symbol, both the terminal and the base station can simultaneously transmit and receive on the uplink and downlink. In a full duplex symbol, the terminal and the base station may simultaneously transmit and receive in an available frequency region (or frequency resource, frequency band), or may simultaneously transmit and receive in a partial frequency region (i.e., transmission or reception may be performed in other frequency regions). In this case, the frequency region in which the base station or terminal transmits and receives may not be adjacent, but may have a frequency interval (also called a frequency gap). Furthermore, for the purpose of, for example, reducing interference, either the terminal or the base station may simultaneously transmit and receive (i.e., the other may transmit or receive).

[0121] In addition, full duplex operation may be applied to an operation in which a terminal can simultaneously transmit and receive sidelinks, or to an operation in which a terminal can simultaneously transmit and receive sidelinks and uplinks or downlinks.

[0122] (Antenna Port) In one embodiment of the present disclosure, an antenna port refers to a logical antenna (antenna group) consisting of one or more physical antennas. For example, an antenna port does not necessarily refer to a single physical antenna, but may refer to an array antenna consisting of multiple antennas. For example, the number of physical antennas that an antenna port is composed of is not specified, and the antenna port may be specified as the smallest unit by which a terminal station can transmit a reference signal. Furthermore, an antenna port may also be specified as the smallest unit by which a weighting of a precoding vector is multiplied.

[0123] <5G NR System Architecture and Protocol Stack> The 5G NR system architecture generally assumes an NG-RAN (Next Generation - Radio Access Network) including gNBs. The gNBs provide UE-side termination of the NG radio access user plane (SDAP / PDCP / RLC / MAC / PHY) and control plane (RRC) protocols. The gNBs are connected to each other via an Xn interface. The gNBs are also connected to a Next Generation Core (NGC) via a Next Generation (NG) interface, more specifically to an Access and Mobility Management Function (AMF) (e.g., a specific core entity that performs AMF) via an NG-C interface, and to a User Plane Function (UPF) (e.g., a specific core entity that performs UPF) via an NG-U interface. The NG-RAN architecture is shown in Figure 15 (see, for example, 3GPP TS 38.300 v15.6.0, section 4).

[0124] <RRC connection setup and reconfiguration procedure> This shows the NAS part of the interaction between the UE, gNB, and AMF (5GC entity) when the UE transitions from RRC_IDLE to RRC_CONNECTED (see TS 38.300 v15.6.0).

[0125] RRC is a higher layer signaling protocol used to configure the UE and gNB. The AMF prepares UE context data (including, for example, PDU session context, security keys, UE radio capabilities, UE security capabilities, etc.) and sends it to the gNB along with an INITIAL CONTEXT SETUP REQUEST. The gNB then activates AS security together with the UE. This is done by the gNB sending a SecurityModeCommand message to the UE, and the UE responding with a SecurityModeComplete message to the gNB. The gNB then sends an RRCReconfiguration message to the UE, and upon receiving an RRCReconfigurationComplete from the UE, the gNB performs reconfiguration to set up Signaling Radio Bearer 2 (SRB2) and Data Radio Bearer (DRB). For signaling-only connections, the steps related to RRCReconfiguration are omitted because SRB2 and DRB are not set up. Finally, the gNB notifies the AMF that the setup procedure is complete with an INITIAL CONTEXT SETUP RESPONSE.

[0126] Therefore, the present disclosure provides a 5th Generation Core (5GC) entity (e.g., AMF, SMF, etc.) that includes: a control circuit that, upon operation, establishes a Next Generation (NG) connection with a gNodeB; and a transmitter that, upon operation, transmits an initial context setup message to the gNodeB via the NG connection so that a signaling radio bearer between the gNodeB and a user equipment (UE) is set up. Specifically, the gNodeB transmits Radio Resource Control (RRC) signaling, including a resource allocation configuration information element (IE), to the UE via the signaling radio bearer. The UE then transmits in uplink or receives in downlink based on the resource allocation configuration.

[0127] <QoS Control> The 5G Quality of Service (QoS) model is based on QoS flows and supports both QoS flows that require a guaranteed flow bit rate (Guaranteed Bit Rate QoS flows (GBR)) and QoS flows that do not require a guaranteed flow bit rate (non-GBR QoS flows). Thus, at the NAS level, a QoS flow is the finest granularity of QoS classification in a PDU session. A QoS flow is identified within a PDU session by a QoS Flow ID (QFI) carried in an encapsulation header over the NG-U interface.

[0128] For each UE, 5GC establishes one or more PDU sessions. For each UE, the NG-RAN establishes, for example, at least one Data Radio Bearer (DRB) for each PDU session. Additional DRBs for the QoS flows of that PDU session can be configured later (when this is up to the NG-RAN). The NG-RAN maps packets belonging to different PDU sessions to different DRBs. NAS-level packet filters in the UE and 5GC associate UL and DL packets with QoS flows, while AS-level mapping rules in the UE and NG-RAN associate UL and DL QoS flows with DRBs.

[0129] (Open-RAN) The base station described in each embodiment (for example, a 5G NR base station called a gNB) may be configured with three functional modules: a Centralized Unit (CU), a Distributed Unit (DU), and a Radio Unit (RU).

[0130] A CU may be referred to as a centralized node, aggregation node, central station, aggregation station, or centralized unit. A DU may be referred to as an O-RAN Distributed Unit (O-DU), distributed node, distributed station, or distributed unit. An RU may be referred to as an O-RAN Radio Unit (O-RU), radio equipment, radio node, radio station, antenna unit, or radio unit.

[0131] There are several split options for the functional split configuration (or functional split point) between CU, DU, and RU. The term "functional split point" is sometimes referred to as "split," "option," or "split option."

[0132] Examples of "division options" include the following division options 1 to 8. The functions of the base station described in each embodiment may be divided into a CU, a DU, and an RU by any of the following division options 1 to 8. For example, the CU, DU, and RU may be functionally divided, or the functions may be divided only between the CU and DU or only between the DU and RU. (1) Segmentation option 1: Between RRC (radio resource control) and PDCP (2) Segmentation option 2: Between PDCP and RLC (High-RLC) (3) Segmentation option 3: Between High-RLC and Low-RLC (4) Segmentation option 4: Between RLC (Low-RLC) and MAC (High-MAC) (5) Segmentation option 5: Between High-MAC and Low-MAC (6) Segmentation option 6: Between MAC (Low-MAC) and PHY (High-PHY) (7) Segmentation option 7: Between High-PHY and Low-PHY (8) Segmentation option 8: Between PHY (Low-PHY) and RF

[0133] The functional split point between the CU and O-DU may be split option 2. The section between the CU and O-DU is called midhaul, and the F1 interface is specified by 3GPP. The section between the O-DU and O-RU is called fronthaul, and the functional split point may be split option 7-2x, which is adopted as the O-RAN fronthaul specification.

[0134] Figure 16 shows an example of functional division of the gNB base station functions into CU, O-DU, and O-RU using Split Option 2 and Split Option 7-2x.

[0135] The CU may have, for example, a radio resource control (RRC) function, a service data adaptation protocol (SDAP) function, and a packet data convergence protocol (PDCP) function.

[0136] The O-DU may include, for example, a radio link control (RLC) function, a MAC function, and a higher physical layer (HIGH-PHY) function. The HIGH-PHY function may include an encoding function, a scrambling function, a modulation function, a layer mapping function, a precoding function, and a resource element (RE) mapping function for downlink (DL) transmission. The HIGH-PHY function may also include a decoding function, a descrambling function, a demodulation function, a layer demapping function, and a resource element (RE) demapping function for uplink (UL) reception.

[0137] The O-RU may have, for example, a LOW-PHY function and an RF function. The LOW-PHY function may also have, for downlink transmission, a beamforming function, an IFFT (Inverse First Fourier Transform) + CP (Cyclic Prefix) assignment function, and a D / A (Digital to Analog) conversion function. The LOW-PHY function may also have, for uplink reception, an A / D (Analog to Digital) conversion function, a CP removal + FFT (First Fourier Transform) function, and a beamforming function.

[0138] In addition, if the O-DU does not have a precoding function, the O-RU may have a precoding function.

[0139] The O-RU may have functionality related to LBT (listen before talk).

[0140] The evolving Common Public Radio Interface (eCPRI) is specified as the communication method between the O-DU and O-RU in Split Option 7-2x. In Split Option 7-2x, eCPRI transmits and receives sampling sequences of the in-phase (I) and quadrature (Q) components of OFDM signals in the frequency domain, as well as information used for beamforming in antennas and time synchronization signals.

[0141] Information transmitted by the signals described in each embodiment (PDCCH, PUCCH, PDSCH, PUSCH, MAC CE, RRC, etc.) may be transmitted between the O-DU and the O-RU via the eCPRI User Plane (U-Plane) or Control Plane (C-Plane).

[0142] When the functions described in each embodiment are performed in the O-RU by functional division, the O-DU may control the O-RU by transmitting information for controlling the functions via a control signal (e.g., eCPRI) between the O-DU and the O-RU.

[0143] When the functions described in each embodiment are performed in the O-DU by functional division, the O-RU may receive the results of the functions performed in the O-DU via a control signal (e.g., eCPRI) and control the O-RU based on the received results.

[0144] The CU, O-DU, and O-RU may be deployed in physically different devices with their respective functions connected by optical fiber or the like, or some or all of their functions may be deployed in the same physical device.

[0145] The CU and O-DU may be logical entities implemented as software running on a server in the cloud or the like as a virtualized RAN (virtual Radio Access Network: vRAN). Also, some or all of the functions of the CU and O-DU may be provided as a virtualized network function (Network Functions Virtualization: NFV) service.

[0146] The transceiver does not have to be a radio transceiver, but may be, for example, a network transceiver, an optical transceiver, etc. The radio resources allocated by the O-DU may be resources for wireless communication between the O-RU and the UE.

[0147] The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may also be called an IC, system LSI, super LSI, or ultra LSI.

[0148] The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

[0149] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology may be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0150] The present disclosure may be implemented in any type of apparatus, device, or system (collectively referred to as a communications apparatus) that has a communications function. The communications apparatus may include a radio transceiver and processing / control circuitry. The radio transceiver may include a receiver and a transmitter, or both functions. The radio transceiver (transmitter and receiver) may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0151] The communication devices are not limited to portable or mobile devices, but also include any kind of non-portable or fixed equipment, devices, and systems, such as smart home devices (such as home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0152] Communications include data communications via cellular systems, wireless LAN systems, communication satellite systems, and the like, as well as data communications via combinations of these.

[0153] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0154] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0155] A terminal according to one embodiment of the present disclosure includes a first receiving circuit, a second receiving circuit that operates with less power than the first receiving circuit and receives a wake-up signal for a low-power receiver that wakes up the first receiving circuit from a sleep state, and a control circuit that controls the terminal in accordance with control information received by the second receiving circuit or the first receiving circuit for controlling the operation of the terminal with respect to a secondary cell.

[0156] In one embodiment of the present disclosure, the first receiving circuit is capable of receiving the control information in a DCI format, and the second receiving circuit receives the control information together with the wake-up signal.

[0157] In one embodiment of the present disclosure, the second receiving circuit is capable of demodulating and decoding the overlaid sequence and receives the control information allocated to the free space obtained by applying the overlaid sequence to the wake-up signal.

[0158] In one embodiment of the present disclosure, the second receiving circuit receives, together with the wake-up signal, immediate-after control information from the control information, which indicates control immediately after the first receiving circuit is started up in response to receiving the wake-up signal, and the first receiving circuit receives information from the control information other than the immediate-after control information after starting up from a sleep state in response to receiving the wake-up signal.

[0159] In one embodiment of the present disclosure, the second receiving circuit does not receive the control information, and the first receiving circuit receives control information for controlling the operation of the terminal with respect to the secondary cell after waking up from a sleep state in response to receiving the wake-up signal.

[0160] A base station according to one embodiment of the present disclosure includes a control circuit that generates control information for controlling the operation of a terminal with respect to a secondary cell, and a transmission circuit that transmits a wake-up signal for a low-power receiver and the control information to the terminal.

[0161] In one embodiment of the control method of the present disclosure, a terminal receives a wake-up signal intended for a low-power receiver, wakes up from a sleep state in response to receiving the wake-up signal, and controls the terminal in response to control information for controlling the operation of the terminal with respect to a secondary cell.

[0162] In one embodiment of the control method of the present disclosure, a base station generates control information for controlling the operation of a terminal with respect to a secondary cell, and transmits a wake-up signal for a low-power receiver and the control information to the terminal.

[0163] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2024-131916, filed on August 8, 2024, are incorporated herein by reference in their entirety.

[0164] One embodiment of the present disclosure is useful in wireless communication systems.

[0165] 100 Terminal 110 LR 120 MR 200 Base station

Claims

1. A terminal comprising: a first receiving circuit; a second receiving circuit that operates with less power than the first receiving circuit and receives a wake-up signal for a low-power receiver that wakes up the first receiving circuit from a sleep state; and a control circuit that controls the terminal in accordance with control information for controlling the operation of the terminal with respect to a secondary cell, the control information being received by the second receiving circuit or the first receiving circuit.

2. The terminal according to claim 1, wherein the first receiving circuit is capable of receiving the control information in a DCI (Downlink Control Information) format, and the second receiving circuit receives the control information together with the wake-up signal.

3. The terminal according to claim 2, wherein the second receiving circuit is capable of demodulating and decoding an overlaid sequence and receives the control information allocated to an empty space obtained by applying the overlaid sequence to the wake-up signal.

4. The terminal according to claim 1, wherein the second receiving circuit receives, together with the wake-up signal, part of the control information that indicates control immediately after the first receiving circuit has been started up in response to receiving the wake-up signal, and the first receiving circuit receives other control information from the control information other than the part of the control information after starting up from a sleep state in response to receiving the wake-up signal.

5. The terminal according to claim 1, wherein the second receiving circuit does not receive the control information, and the first receiving circuit receives control information for controlling the operation of the terminal with respect to the secondary cell after waking up from a sleep state in response to receiving the wake-up signal.

6. A base station comprising: a control circuit that generates control information for controlling the operation of a terminal with respect to a secondary cell; and a transmission circuit that transmits a wake-up signal for a low-power receiver and the control information to the terminal.

7. A control method in which a terminal receives a wake-up signal intended for a low-power receiver, wakes up from a sleep state in response to receiving the wake-up signal, and controls the terminal in response to control information for controlling the operation of the terminal with respect to a secondary cell.

8. A control method in which a base station generates control information for controlling the operation of a terminal with respect to a secondary cell, and transmits a wake-up signal for a low-power receiver and the control information to the terminal.

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