COMMUNICATION EQUIPMENT AND METHODS

Abstract

The invention relates to a communication device having a receiving circuit that receives signals, and a control circuit that causes the configuration relating to the transmission moratorium period to vary according to whether the transmitting signal source belongs to the same group relating to cooperative communication as the communication device.

Description

Communication device and communication method

[0001] The present disclosure relates to a communication device and a communication method.

[0002] A task group (TG) is currently developing the technical specifications for 802.11be (hereinafter referred to as "11be") as the successor standard to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, 802.11ax (hereinafter referred to as "11ax").

[0003] IEEE 802.11-19 / 1582r2, Coordinated AP time / Frequency Sharing in a Transmit Opportunity in 11beIEEE 802.11-20 / 596r1, AP candidate set follow upIEEE 802.11-19 / 1019r0, Virtual BSS For Multi AP CoordinationIEEE Std 802.11axTM-2021IEEE 802.11-20 / 644r0, NAV Setting in Multi-AP Operation

[0004] However, there is room for further study on the control method of cooperative communication in wireless communication.

[0005] Non-limiting examples of the present disclosure contribute to providing a communication device and a communication method that improve communication efficiency of cooperative communication in wireless communication.

[0006] A communication device according to an embodiment of the present disclosure includes a receiving circuit that receives a signal, and a control circuit that changes a setting related to a transmission inhibit period depending on whether a sender of the signal belongs to a group related to cooperative communication common to the communication device.

[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 improve communication efficiency of cooperative communication in wireless communication.

[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] MAP coordination using user information MAP coordination information element Figure showing an example of NAV control in MAP coordination according to method 1 Figure showing an example of NAV control in MAP coordination according to method 1 Figure showing an example of NAV control in MAP coordination according to method 2 Figure showing an example of NAV control in MAP coordination according to method 2 Figure showing an example of User Info field in Trigger frame according to method 2-1 MAP using multiple Transmission Opportunities (TXOPs) FIG. 1 shows an example of the operation of sequential sounding in MAP coordination. FIG. 2 shows an example of the operation of joint sounding in MAP coordination. FIG. 3 shows an example of MAP sounding. FIG. 4 shows an example of MAP sounding. FIG. 5 shows an example of a trigger frame format including multiple pieces of user information. FIG. 6 shows an example of NAV control based on the transmission order of user information.Figure showing an example of NAV control based on common information in a frameFigure showing an example of the User Info field in a Trigger frameFigure showing an example of NAV control based on user informationFigure showing an example of the User field in an Extremely High Throughput (EHT)-SIGFigure showing an example of the STA Info field in a Null Data Packet Announcement (NDPA)Figure showing an example of a Universal SIG (U-SIG)Figure showing an example of Triggered TXOP Sharing operation in TXOP Sharing Mode=1Figure showing an example of Triggered TXOP Sharing operation in TXOP Sharing Mode=2

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

[0012] [About Multi-AP (MAP) coordination] In 11be, Multi-AP (MAP) coordination (also called "cooperative communication") is being considered, in which multiple access points (also called "base stations", hereinafter referred to as "APs (Access Points)") cooperate with each other to transmit and receive data (see, for example, non-patent document 1).

[0013] In MAP coordination, for example, an AP that acquires a channel usage period (TXOP: Transmission Opportunity) is called a “Sharing AP.” The AP may acquire the TXOP by, for example, Carrier Sense Multiple Access / Collision Avoidance (CSMA / CA).

[0014] In MAP coordination, for example, an AP that is cooperatively controlled by a Sharing AP is called a "Shared AP."

[0015] Also, in MAP coordination, for example, a terminal (also called a station (STA) or non-AP STA) that belongs to (e.g., belongs to or associates with) a Sharing AP may be called a "Sharing STA," and a STA that belongs to a Shared AP may be called a "Shared STA."

[0016] Fig. 1 is a diagram showing an example of a control method for MAP coordination. In Fig. 1, it is assumed that the MAP coordination process is divided into three phases: a "Tx indication and request" phase, a "Schedule allocation" phase, and a "Data Tx" phase.

[0017] 2 is a diagram illustrating an example of negotiation (e.g., Tx indication and request phase and Schedule allocation phase) between APs (e.g., Sharing AP and Shared AP) in MAP coordination. In the example of FIG. 2, AP1 may be a Sharing AP, and AP2 and AP3 may be Shared APs.

[0018] As shown in Figure 2, in the first Tx indication and request phase, the Sharing AP (AP1) sends a Coordinated AP TXOP Indication (CTI) frame to the Shared APs (AP2 and AP3) to request a response regarding whether or not they will participate in MAP coordination. In response to the CTI from AP1, the Shared APs (AP2 and AP3) send a Coordinated AP TXOP Request (CTR) frame to the Sharing AP (AP1) to indicate whether or not they will participate in MAP coordination.

[0019] 2, in the second Schedule allocation phase, the Sharing AP (AP1) transmits a Coordinated AP TXOP AP Schedule (CTAS) frame to the Shared APs (AP2 and AP3) to notify them of allocation information such as available resource information (e.g., frequency resources and time resources) and transmission start times. Next, the Sharing AP (AP1) and the Shared APs (AP2 and AP3) transmit, for example, a Coordinated AP TXOP Local Schedule (CTLS) frame to notify terminals under each AP of available resource information and allocation information such as transmission start times.

[0020] Then, as shown in Fig. 1, in the third stage Data Tx (e.g., Data Tx phase), the AP and STA perform cooperative transmission based on the allocation information. For example, cooperative transmission in the Data TX phase may include Joint Transmission (JT), Corrdinated Beamforming (CBF), Coordinated Spatial Reuse (CSR), Coordinated Orthogonal Frequency Division Multiple Access (COFDMA), or Coordinated Time Division Multiple Access (CTDMA). In addition, cooperative transmission may be either downlink cooperative transmission (Downlink cooperative transmission) or uplink cooperative transmission (Uplink cooperative transmission).

[0021] The control method of MAP coordination shown in FIGS. 1 and 2 is an example, and is not limited to the method shown in FIGS.

[0022] [Regarding Coordination Groups] Furthermore, examples of groups that perform MAP coordination (also referred to as "coordination groups" or "coordination groups") include an "AP candidate set" and a "Virtual Basic Service Set (Virtual BSS)" (see, for example, Non-Patent Documents 2 and 3).

[0023] FIG. 3 is a diagram illustrating an example of an AP candidate set and a Virtual BSS.

[0024] 3, the AP candidate set may be a group consisting of multiple APs (for example, AP1, AP2, AP3, and AP4). For example, a Sharing AP and a Shared AP that perform MAP coordination may be selected from the APs included in the AP candidate set.

[0025] 3, a Virtual BSS may be a group consisting of multiple Basic Service Sets (BSSs) (e.g., BSS1 and BSS2) for MAP coordination. APs participating in a Virtual BSS may have a common Service Set identifier (SSID). APs included in a Virtual BSS may share information about STAs belonging to each BSS (e.g., STA Association identifiers (AIDs)).

[0026] [About Transmission Prohibition Period (NAV: Network Allocation Vector)] An AP or STA (hereinafter, for example, referred to as a "terminal" or, for convenience, as an "AP / STA") that has acquired a TXOP may notify other APs / STAs of information about the transmission prohibition period (Network Allocation Vector (NAV)) by including it in a transmission signal. By notifying the NAV, other APs / STAs are inhibited from accessing the channel for a certain period by virtual carrier sense (for example, by virtually regarding the carrier sense state as busy). The NAV period may be notified, for example, in the Duration / ID subfield of the Medium Access Control (MAC) header or the TXOP subfield of the SIG field of the preamble.

[0027] The AP / STA, for example, updates a counter (e.g., a NAV counter) based on the period of the notified NAV, decrements the NAV counter according to the elapsed time, and recognizes that the virtual carrier sense state is idle if the NAV counter is 0.

[0028] In 11ax, for example, two types of NAV are used: "intra-BSS NAV" and "Basic NAV" (see, for example, Non-Patent Document 4).

[0029] FIG. 4 is a diagram showing an example of intra-BSS NAV and Basic NAV.

[0030] In the example of Fig. 4, AP1, STA1, and STA2 belong to BSS1, and STA3 belongs to BSS2. Also in the example of Fig. 4, AP1 acquires a TXOP and transmits a transmission signal (e.g., Request-To-Send (RTS)) to STA1, and STA1 transmits a response signal to the RTS (e.g., Clear-To-Send (CTS)) to AP1. Then, AP1 transmits transmission data (Tx Data) to STA1, and STA1 transmits a response signal (Acknowledge (Ack)) to the transmission data to AP1.

[0031] As shown in Figure 4, when a signal addressed to STA1 or a signal addressed to AP1 is transmitted or received, STA2 and STA3 may perform control (e.g., setting, updating, etc.) regarding NAV based on information contained in the signal addressed to STA1 or AP1 (e.g., information regarding TXOP).

[0032] For example, when the NAV is notified by a signal transmitted from an AP / STA belonging to the BSS to which the STA belongs (hereinafter referred to as the "common BSS"; BSS1 in FIG. 4), as in the case of STA2 shown in FIG. 4, the Intra-BSS NAV is updated.

[0033] In addition, when the NAV is notified by a signal transmitted from an AP / STA belonging to a BSS (hereinafter referred to as "Overlapped BSS (OBSS)") different from the BSS to which the STA belongs (e.g., BSS2), as in the case of STA3 shown in Figure 4, the Basic NAV is updated.

[0034] The Intra-BSS NAV and the Basic NAV may each be managed by, for example, a separate NAV counter. For example, an AP / STA supporting 11ax recognizes that the virtual carrier sense state is idle if the NAV counters for both the Intra-BSS NAV and the Basic NAV are zero.

[0035] The control method for NAV in MAP coordination has not been fully studied. For example, in the NAV control method for 11ax, coordinated transmission in MAP coordination may be hindered by NAV. For this reason, the NAV control method in MAP coordination is being studied (for example, see Non-Patent Document 5).

[0036] Fig. 5 is a diagram showing an example of a NAV control method in MAP coordination. In the example shown in Fig. 5, AP1 (Sharing AP) and STA1 belong to BSS1, and AP2 (Shared AP) and STA2 belong to BSS2.

[0037] In the example shown in FIG. 5 , AP1 transmits a request to participate in MAP coordination (CTI) to AP2. Here, AP1 may notify surrounding APs / STAs of the TXOP period using the CTI to AP2. In FIG. 5 , STA2, which belongs to a different BSS (BSS2) from AP1, receives the CTI addressed to AP2 from AP1 and updates its Basic NAV based on the CTI. STA2 may set its NAV period, for example, based on the TXOP acquired by AP1. As shown in FIG. 5 , because STA2 updates its Basic NAV, even if AP2 transmits a trigger frame (TF) to STA2 instructing it to transmit an uplink signal (UL transmission), STA2 suspends UL transmission based on Basic NAV. Thus, NAV control may prevent coordinated communication through MAP coordination.

[0038] There is discussion about how to solve the problem of NAV control not allowing cooperative communication.

[0039] FIG. 6 is a diagram showing an example of a NAV control method, which is the first solution.

[0040] As shown in Fig. 6, the TXOP acquired by the sharing AP (e.g., AP1) is updated in multiple parts. For example, in Fig. 6, the period of the first TXOP (TXOP1) notified by the CTI transmitted by AP1 may be set to be before the UL transmission of each STA (e.g., STA1 and STA2). Furthermore, the period of the second TXOP (TXOP2) notified by the Trigger frame transmitted by each AP (e.g., AP1 and AP2) may be set to be, for example, until the timing when each AP (e.g., AP1 and AP2) finishes transmitting a response (e.g., Ack) signal in response to the UL transmission of each STA (e.g., STA1 and STA2).

[0041] In Fig. 6, for example, when STA2 receives a CTI addressed to AP2 from AP1, it updates its Basic NAV based on TXOP1 included in the received CTI. Therefore, as shown in Fig. 6, the NAV set in STA2 can be canceled before STA2's UL transmission (e.g., the NAV counter becomes zero). Also, as shown in Fig. 6, since the Trigger frame notifying the duration of TXOP2 is a signal addressed to STA2, STA2 does not update its NAV even when it receives the Trigger frame. Therefore, in Fig. 6, STA2 is able to perform UL transmission (e.g., cooperative communication).

[0042] In the method shown in FIG. 6, the number of parts into which a TXOP is divided is not limited to two, but may be three or more.

[0043] FIG. 7 is a diagram showing an example of a NAV control method, which is the second solution.

[0044] As shown in Fig. 7, when STA2 receives a request to participate in MAP coordination (CTI) sent from AP1 to AP2, it updates its Basic NAV based on the TXOP included in the received CTI. In Fig. 7, for example, when a shared STA (STA2) belonging to a shared AP (AP2) receives a trigger frame sent from the shared AP, it may temporarily ignore the Basic NAV. As a result, as shown in Fig. 7, STA2 can perform UL transmission (e.g., cooperative communication) even if the NAV counter of the Basic NAV is non-zero.

[0045] An example of a NAV control method in MAP coordination has been described above.

[0046] For example, even in the NAV control methods shown in FIGS. 6 and 7, there is a possibility that the AP / STA may not be able to transmit a signal in MAP coordination.

[0047] For example, Fig. 8 is a diagram showing an example of cooperative communication using CTDMA. As shown in Fig. 8, in cooperative communication using CTDMA, AP1 and AP2 may control UL transmission for STA1 and STA2 using different time resources. Also, in Fig. 8, similar to Fig. 6, the TXOP acquired by AP1 (Sharing AP) may be divided into multiple TXOPs (e.g., TXOP1, TXOP2, and TXOP3) based on the timing of UL transmission of each STA.

[0048] For example, as shown in Fig. 8, when STA2 receives a request to participate in MAP coordination (CTI) sent from AP1 to AP2, it updates the Basic NAV based on TXOP1 included in the received CTI. Also, as shown in Fig. 8, when AP2 and STA2 receive a Trigger frame sent from AP1 to STA1, they update the Basic NAV based on TXOP2 included in the received Trigger frame.

[0049] 8, AP2 updates the Basic NAV based on the Trigger frame transmitted by AP1 to STA1, and therefore stops transmitting the Trigger frame to STA2. In this way, coordinated transmission in MAP coordination may be hindered by the NAV.

[0050] Furthermore, for example, in the NAV control method, which is the second solution described above, when a Shared STA is triggered to perform UL transmission by the Shared AP to which the STA belongs, the Shared STA may ignore the configured Basic NAV and perform UL transmission. Here, for example, if a Shared AP not participating in cooperative transmission fails to receive a signal (e.g., a signal including information about TXOP) from a Sharing AP, the Shared STA may update its Basic NAV, while the Shared AP may not update its Basic NAV. In this case, when a Shared AP not participating in cooperative transmission transmits a Trigger frame, the Shared STA may ignore the configured Basic NAV and perform UL transmission. Therefore, in this case, for example, a conflict may occur between the UL transmission of the Shared STA not participating in cooperative transmission and the cooperative transmission. In this way, a conflict may occur due to the rule of ignoring the configured NAV.

[0051] In one non-limiting embodiment of the present disclosure, a method for suppressing the interruption of transmission and reception between APs and STAs due to NAV control in MAP coordination and improving communication efficiency of cooperative communication in MAP coordination will be described.

[0052] In a non-limiting embodiment of the present disclosure, the AP / STA may determine the control regarding the NAV based on, for example, the source information of the received signal. According to a non-limiting embodiment of the present disclosure, by switching the control method regarding the NAV based on the cooperative group that performs MAP coordination, cooperative transmission can be appropriately performed in MAP coordination without being hindered by the NAV.

[0053] [Configuration of Wireless Communication System] A wireless communication system according to an embodiment of the present disclosure includes at least one coordination group that performs MAP coordination. The coordination group includes, for example, multiple APs 100 and at least one STA 200. For example, in Downlink (DL) communication, the AP 100 corresponds to a "downlink wireless transmitter" and the STA 200 corresponds to a "downlink wireless receiver." Furthermore, in Uplink (UL) communication, the AP 100 corresponds to an "uplink wireless receiver" and the STA 200 corresponds to an "uplink wireless transmitter." For example, the AP 100 transmits a DL signal to another AP 100 or STA 200. Furthermore, for example, the STA 200 transmits a UL signal based on a signal received from the AP 100.

[0054] In the following, as an example, MAP coordination is performed by a plurality of APs 100 and a plurality of STAs 200. For example, as shown in Fig. 9, a method will be described in which two APs 100 (AP1 and AP2) transmit and receive control signals related to MAP coordination between the APs, AP1 and AP2 transmit trigger frames to STA1 and STA2 by CTDMA, and STA1 and STA2 transmit UL signals.

[0055] As shown in Fig. 9, AP1 and STA1 may belong to BSS1, and AP2 and STA2 may belong to BSS2. Also, as shown in Fig. 9, it is assumed that BSS1 and BSS2 at least partially overlap.

[0056] FIG. 10 is a sequence diagram illustrating an example of an operation related to MAP coordination by the AP 100 and the STA 200 in a wireless communication system according to an embodiment of the present disclosure.

[0057] In the example shown in FIG. 10, AP1 acquires the TXOP and acts as a Sharing AP that takes the lead in MAP coordination.

[0058] For example, the AP1 transmits a request signal (for example, CTI) to participate in MAP coordination to the AP2 (S101).

[0059] The AP2 performs, for example, a process of receiving the Multi-AP coordination participation request signal (S102). For example, the AP2 may determine whether or not to participate in MAP coordination based on capability information (Capability) related to MAP coordination.

[0060] Furthermore, STA1 and STA2, which are not the destination (e.g., AP2) of the MAP coordination participation request signal transmitted from AP1, may each perform control processing related to the NAV (e.g., updating the NAV counter or selecting the type of NAV counter to update) (S103-1, S103-2). For example, STA1 and STA2 may determine NAV control based on information regarding the NAV period notified by the MAP coordination participation request signal and whether AP1, the sender of the MAP coordination participation request signal, belongs to a common BSS. Thereafter, when STA1 and STA2 receive a signal with a destination different from the STA (e.g., when the AIDs of STA1 and STA2 are not included in the destination information of the received signal), they may perform NAV control processing similar to S103-1 and S103-2 (e.g., S106-1, S106-2, S109-1 and S109-2).

[0061] The AP2 transmits, for example, MAP coordination participation response information (for example, CTR) including whether or not to participate in MAP coordination to the AP1 (S104).

[0062] AP1 performs a process of receiving a Multi-AP coordination participation response information signal (S105). For example, AP1 may determine a MAP coordination method (e.g., JT, CBF, CSR, COFDMA, or CTDMA) based on information about APs (e.g., Shared APs) participating in MAP coordination and perform scheduling. AP1 then transmits, for example, MAP coordination scheduling information to Shared APs (e.g., including AP2) (S107). AP2 performs, for example, a process of receiving the MAP coordination scheduling information from AP1 (S108).

[0063] The MAP coordination scheduling information may include, for example, information about the cooperating APs 100 (e.g., the SSID of the AP 100 or the AID of the STA 200), resource information available to each AP 100 (e.g., frequency resource information or time resource information), information about weighting of amplitude or phase in coordinated transmission (also called steering, spatial mapping, or transmit precoding), or transmit power information.

[0064] AP1 and AP2 transmit, for example, MAP coordination local scheduling information (for example, CTLS) to the STAs under each AP (S110-1 and S110-2).

[0065] The Multi-AP coordination local scheduling information may include, for example, resource information (e.g., frequency resource information or reception timing information) for the STA 200 to receive a DL MAP coordination signal, or resource information (e.g., frequency resource information, transmission timing information, or transmission power information) for the STA 200 to transmit a UL MAP coordination signal. Each AP 100 and STA 200 performs coordinated transmission based on the Multi-AP coordination scheduling information and the Multi-AP coordination local scheduling information. In the example shown in Figure 10, an example of coordinated transmission is shown in which the STA 200 transmits a UL signal in CTDMA. Note that the coordinated transmission method is not limited to CTDMA, and other methods may be used.

[0066] For example, AP1 transmits a Trigger frame to STA1 within the time resource notified by the MAP coordination scheduling information (S111-1). STA1 performs reception processing of the Trigger frame (S112-1) and transmits an UL signal to AP1 based on the control information included in the Trigger frame (S113-1). AP1 performs reception processing of the UL signal (S114-1) and transmits a response signal (Ack) to STA1 based on, for example, the error detection result (S115-1).

[0067] In the case of CTDMA, AP2 and STA2 may then perform the same transmission and reception processing as AP1 and STA1 (S111-2 to S115-2).

[0068] An example of the operation regarding MAP coordination by the AP 100 and the STA 200 has been described above.

[0069] 11 is a block diagram illustrating a configuration example of a portion of an AP 100 or a STA 200 according to an embodiment of the present disclosure. In the AP 100 or the STA 200 (e.g., corresponding to a communication device) illustrated in FIG. 11 , a receiver (e.g., corresponding to a receiving circuit) receives a signal. A controller (e.g., corresponding to a control circuit) changes a setting related to a transmission inhibit period (NAV) depending on whether the sender of the signal belongs to a group (a common cooperative group) related to cooperative communication common to the communication device (e.g., the AP 100 or the STA 200).

[0070] [Configuration example of AP 100] Fig. 12 is a block diagram showing a configuration example of AP 100 (e.g., a downlink wireless transmission device or an uplink wireless reception device). The AP 100 shown in Fig. 12 may include, for example, a wireless reception unit 101, a preamble demodulation unit 102, a data demodulation unit 103, a data decoding unit 104, a NAV control unit 105, a scheduling unit 106, a data generation unit 107, a data encoding unit 108, a data modulation unit 109, a preamble generation unit 110, and a wireless transmission unit 111.

[0071] For example, at least one of the preamble demodulation unit 102, data demodulation unit 103, data decoding unit 104, NAV control unit 105, scheduling unit 106, data generation unit 107, data encoding unit 108, data modulation unit 109, and preamble generation unit 110 may be included in the control unit shown in Figure 11, and the radio receiving unit 101 may be included in the transmission unit shown in Figure 11.

[0072] The wireless receiving unit 101 receives a signal transmitted from another AP 100 (e.g., a downlink wireless transmitting device) or a STA 200 (e.g., a downlink wireless receiving device) via an antenna, and performs wireless receiving processing such as down-conversion and Analog-to-Digital (A / D) conversion on the received signal. The wireless receiving unit 101 divides the received signal after wireless receiving processing into a preamble portion (also called a preamble signal) and a data portion (also called a data signal), and outputs the preamble signal to the preamble demodulation unit 102 and the data signal to the data demodulation unit 103.

[0073] The preamble demodulation unit 102 may extract a control signal included in the preamble signal by performing demodulation processing such as a Fourier transform (e.g., Fast Fourier Transform (FFT)) on the preamble signal input from the radio receiving unit 101. The control signal may include reception control information used for demodulating and decoding a data signal, such as a frequency bandwidth (BW), a modulation and coding scheme (MCS), or an error correction code.

[0074] The preamble demodulation unit 102 also performs channel estimation based on, for example, a reference signal included in the preamble signal, and derives a channel estimation value. The preamble demodulation unit 102 outputs, for example, reception control information to the data demodulation unit 103 and the data decoding unit 104, and outputs the channel estimation value to the data demodulation unit 103.

[0075] In addition, if the preamble signal contains destination information (e.g., the STA-ID of the user information contained in the SIG field) or information regarding the TXOP, the preamble demodulation unit 102 outputs this information to the NAV control unit 105.

[0076] Data demodulation section 103 performs a Fourier transform (e.g., FFT) on the data signal input from radio reception section 101, and demodulates the data signal after FFT based on the reception control information and channel estimation value input from preamble demodulation section 102. Data demodulation section 103 outputs the demodulated data signal to data decoding section 104.

[0077] The data decoding unit 104 decodes the demodulated data signal input from the data demodulation unit 103, for example, based on the reception control information input from the preamble demodulation unit 102. For example, the data decoding unit 104 may perform error detection such as a Cyclic Redundancy Check (CRC) on the decoded data signal. For example, if there is no error in the decoded data signal (in other words, a decoding error), the data decoding unit 104 outputs the MAC header and destination information (for example, the AID of the user information included in the trigger frame) included in the decoded data signal to the NAV control unit 105. Furthermore, the data decoding unit 104 outputs, for example, the decoded data signal and the error detection result to the scheduling unit 106.

[0078] The NAV control unit 105 controls the NAV using, for example, at least one of the destination information and TXOP information input from the preamble demodulation unit 102 and the MAC header and destination information input from the data decoding unit 104 .

[0079] For example, the NAV control unit 105 may determine whether to update the NAV for each NAV type individually, depending on whether the destination of the data signal is the AP 100, based on the destination information or the source address included in the MAC header. In other words, the NAV control unit 105 may change the NAV settings depending on whether the source of the data signal belongs to a common cooperative group with the AP 100. When updating the NAV, the NAV control unit 105 may determine the period of the NAV to be updated, based on, for example, at least one of the TXOP information and the value of the Duration / ID field included in the MAC header. The NAV control unit 105 outputs the value of the NAV counter for each NAV type to the scheduling unit 106.

[0080] The scheduling unit 106 may determine whether to perform transmission in MAP coordination based on, for example, the value of a NAV counter input from the NAV control unit 105. If transmission is to be performed, the scheduling unit 106 determines scheduling information for the coordination signal. The scheduling information for the coordination signal may include, for example, a method for coordinated transmission in MAP coordination, information about users participating in the coordinated transmission, information about resources individually available to each user, and information such as an MCS or error correction code. The scheduling unit 106 may also determine the scheduling information for the coordination signal based on scheduling information notified by a decoded data signal input from the data decoding unit 104. The scheduling unit 106 outputs the scheduling information for the coordination signal to the data generation unit 107, the data encoding unit 108, the data modulation unit 109, and the preamble generation unit 110. If transmission is not to be performed using NAV, the scheduling unit 106 does not need to output scheduling information to the data generation unit 107, the data encoding unit 108, and the data modulation unit 109.

[0081] The data generation unit 107 generates a data series to be transmitted to the AP 100 (e.g., a downlink wireless transmission device) or the STA 200 (e.g., a downlink wireless reception device) based on, for example, the scheduling information of the cooperative signal input from the scheduling unit 106, and outputs the data series to the data encoding unit 108.

[0082] For example, the data sequence transmitted to the AP 100 may include a response signal to a MAP coordination participation request. Also, for example, the data sequence transmitted to the STA 200 may include resource information for the STA 200 to transmit or receive a coordination signal, a trigger frame for requesting transmission of a UL signal, and a response signal (Ack or Block Ack) to a signal transmitted from the STA 200.

[0083] The data encoding unit 108 encodes the data sequence input from the data generating unit 107 based on, for example, the scheduling information input from the scheduling unit 106 , and outputs the encoded data to the data modulating unit 109 .

[0084] The data modulation unit 109 performs modulation and inverse Fourier transform (e.g., Inverse Fast Fourier Transform (IFFT)) on the coded data input from the data coding unit 108, for example, based on the scheduling information input from the scheduling unit 106, and outputs the modulated data signal to the radio transmission unit 111.

[0085] The preamble generation unit 110 generates a preamble signal based on, for example, scheduling information input from the scheduling unit 106. For example, the preamble generation unit 110 performs modulation and IFFT processing on the preamble signal, and outputs the preamble signal to the radio transmission unit 111.

[0086] The wireless transmission unit 111 generates a wireless frame (which may be called, for example, a "packet signal" or a "packet") including the data signal input from the data modulation unit 109 and the preamble signal input from the preamble generation unit 110. The wireless transmission unit 111 performs wireless transmission processing such as digital-to-analog (D / A) conversion and up-conversion to a carrier frequency on the generated wireless frame, and transmits the signal after the wireless transmission processing to another AP 100 or STA 200 via an antenna.

[0087] <Configuration example of STA 200> Fig. 13 is a block diagram showing a configuration example of STA 200 (e.g., a downlink radio receiving device). STA 200 shown in Fig. 13 may include, for example, a radio receiving unit 201, a preamble demodulating unit 202, a data demodulating unit 203, a data decoding unit 204, a NAV control unit 205, a transmission signal generating unit 206, and a radio transmitting unit 207.

[0088] For example, at least one of the preamble demodulation unit 202, the data demodulation unit 203, the data decoding unit 204, the NAV control unit 205, and the transmission signal generation unit 206 may be included in the control unit shown in Figure 11, and the radio receiving unit 201 may be included in the receiving unit shown in Figure 11.

[0089] Radio receiving section 201 receives a signal transmitted from AP 100 (downlink radio transmitting device) via an antenna and performs radio receiving processing such as down-conversion and A / D conversion on the received signal. Radio receiving section 201 extracts a preamble from the signal after radio receiving processing and outputs it to preamble demodulation section 202. Radio receiving section 201 also extracts a data signal from the signal after radio receiving processing and outputs it to data demodulation section 203.

[0090] The preamble demodulation unit 202 performs demodulation processing such as FFT on the preamble signal input from the radio receiving unit 201, and extracts, for example, reception control information (e.g., BW, MCS, or error correction code) used for demodulating and decoding a data signal from the demodulated preamble signal. The preamble demodulation unit 202 outputs, for example, the extracted reception control information to the data demodulation unit 203 and the data decoding unit 204. The preamble demodulation unit 202 also performs channel estimation based on, for example, a reference signal included in the preamble signal, and derives a channel estimation value. The preamble demodulation unit 202 outputs the channel estimation value to the data demodulation unit 203. If, for example, the preamble signal includes destination information or information related to TXOP, the preamble demodulation unit 202 outputs this information to the NAV control unit 205.

[0091] The data demodulation unit 203 demodulates the data signal input from the radio receiving unit 201, for example, based on the reception control information and channel estimation value input from the preamble demodulation unit 202, and outputs the demodulated data signal addressed to the STA 200 to the data decoding unit 204.

[0092] The data decoding unit 204 decodes the data signal input from the data demodulation unit 203 based on, for example, the reception control information input from the preamble demodulation unit 202, and performs error detection such as CRC. For example, if there is no error in the decoded data, the data decoding unit 204 outputs the MAC header and destination information included in the decoded data to the NAV control unit 205, and outputs the decoded data signal to the transmission signal generation unit 206.

[0093] The NAV control unit 205 controls the NAV using, for example, at least one of the destination information and TXOP information input from the preamble demodulation unit 202 and the MAC header and destination information input from the data decoding unit 204 .

[0094] For example, the NAV control unit 205 may determine whether to update the NAV for each NAV type individually based on the destination information or the source address included in the MAC header (in other words, depending on whether the destination of the data signal is the STA 200). In other words, the NAV control unit 205 may change the NAV settings depending on whether the source of the data signal belongs to a common cooperative group with the STA 200. When updating the NAV, the NAV control unit 205 may determine the period of the NAV to be updated based on, for example, at least one of the TXOP information and the value of the Duration / ID field included in the MAC header. The NAV control unit 205 outputs the value of the NAV counter for each NAV type to the transmission signal generation unit 206.

[0095] The transmission signal generation unit 206 determines whether to perform transmission based on the value of the NAV counter input from the NAV control unit 205. When performing transmission, the transmission signal generation unit 206 generates a transmission signal based on, for example, the decoded data signal input from the data decoding unit 204. For example, if the decoded data signal includes a trigger frame, the transmission signal generation unit 206 may generate a data sequence to be transmitted in a trigger-based physical layer convergence procedure protocol data unit (TB PPDU) based on control information included in the trigger frame. The transmission signal generation unit 206 also generates a data signal by encoding the data sequence and performing modulation and IFFT processing using predetermined frequency resources. The transmission signal generation unit 206 adds a preamble signal to the data signal to generate a radio frame (e.g., a packet signal), and outputs the radio frame to the radio transmission unit 207.

[0096] The wireless transmission unit 207 performs wireless transmission processing such as D / A conversion and upconversion to a carrier frequency on the wireless frame input from the transmission signal generation unit 206, and transmits the signal after wireless transmission processing to the AP 100 via an antenna.

[0097] [Example of Operation of AP 100 and STA 200] Next, an example of operation of the AP 100 and STA 200 according to this embodiment will be described.

[0098] In a non-limiting embodiment of the present disclosure, for example, AP 100 and STA 200 may switch control related to NAV depending on whether the signal is transmitted from a terminal (e.g., AP / STA) belonging to a common cooperative group. In other words, AP 100 and STA 200 may change the setting related to NAV depending on whether the source of the received signal belongs to a common cooperative group.

[0099] Here, the cooperative group may be a group consisting of a plurality of APs 100 (for example, an AP candidate set, or a group of destination APs to which the STA 200 transmits channel quality information), or may be a group consisting of a plurality of APs / STAs (for example, a Virtual BSS). Also, the common cooperative group refers to, for example, a cooperative group to which the AP 100 or STA 200 that receives a signal belongs.

[0100] In the following description, a case where the "terminal" is a non-AP terminal (non-AP STA) will be described as an example, but unless otherwise specified, the "terminal" may refer to either an AP or a non-AP terminal. In other words, a non-limiting embodiment of the present disclosure may be applied to either the operation of AP 100 or the operation of STA 200.

[0101] Here, the terminal (AP / STA) may determine whether or not it belongs to a common cooperative group with the terminal that is the source of the received signal based on an identifier (or identification information) included in the received signal.

[0102] Examples of the identifier include a BSSID, a BSS color, an AP candidate set ID, or a Virtual BSSID.

[0103] The identifier related to the coordination group may be notified, for example, by being included in a MAP coordination operation element shown in Fig. 14. As shown in Fig. 14, the MAP coordination operation element may include an "AP candidate set ID" that identifies the AP candidate set and a "Virtual BSSID" that identifies the Virtual BSS. The AP 100 may notify the STA 200, for example, by including the Multi-AP coordination operation element in at least one of a beacon signal, a probe response signal, and an association response signal.

[0104] 15, at least one of the AP candidate set ID and the Virtual BSSID may be notified as part of the BSSID. The BSSID is notified, for example, by 46 bits excluding the most significant 2 bits of the 48-bit BSSID field. For example, the AP 100 may allocate some of the bits (e.g., 46 bits) used for BSSID allocation in the BSSID field to at least one of the AP candidate set and the Virtual BSSID, and notify the STA 200.

[0105] Furthermore, the terminal (AP / STA) may determine whether or not the terminal belongs to a common cooperative group with the transmitting terminal based on the user information included in the received signal.

[0106] For example, as shown in FIG. 16, a terminal corresponding to information (Transmitter Address (TA)) about the sender of a received signal included in the MAC header of the received signal and a terminal corresponding to user information (User Info) included in the received signal may be determined to be terminals belonging to a common cooperative group.

[0107] For example, a terminal may determine whether it belongs to a common cooperative group depending on whether user information included in a received signal includes user information addressed to the terminal. For example, a terminal (AP / STA) may determine that a sender belongs to a common cooperative group if user information included in a received signal includes user information addressed to the terminal. In other words, a terminal (AP / STA) may determine that a sender does not belong to a common cooperative group if user information included in a received signal does not include user information addressed to the terminal.

[0108] Furthermore, the terminal may determine whether the transmitter of the received signal belongs to a common cooperative group based on information about the cooperative group included in the beacon signal. For example, as shown in FIG. 17 , a "MAP coordination information element" including identifiers of terminals belonging to the cooperative group may be notified to the terminal. The identifier included in the MAP coordination information element may be the identifier of the AP 100 or the identifier of the STA 200. For example, the terminal may determine whether the terminal and the transmitter terminal of the received signal belong to a common cooperative group based on the MAP coordination information element notified in advance and included in the beacon signal.

[0109] In addition, when a cooperative group is a group composed of multiple APs 100, STA 200 may determine whether the terminal and the source terminal of the received signal belong to a common cooperative group depending on whether the cooperative group of the terminal that transmitted the received signal is the same as the cooperative group of the AP 100 to which STA 200 belongs.

[0110] Furthermore, when a cooperative group is a group made up of multiple APs / STAs, APs / STAs that do not participate in cooperative transmission do not need to be included in the cooperative group.

[0111] Next, an example of a NAV control method based on the above-described method will be described.

[0112] [Method 1] In method 1, for example, when a terminal (AP / STA) receives a signal including information about a TXOP from another terminal belonging to a common cooperative group (in other words, when notified), the terminal (AP / STA) does not update (or set) its NAV. In other words, when a terminal (AP / STA) is notified of a TXOP by a signal transmitted from a terminal belonging to the common cooperative group, the terminal (AP / STA) decides not to update its NAV.

[0113] For example, a terminal may determine whether or not the terminal and the source terminal belong to a common cooperative group based on a signal received before or during the MAP coordination process.

[0114] <Example 1 of Method 1> In Example 1 of Method 1, STA 200 does not update NAV when information about TXOP is notified by a signal transmitted from a terminal (AP / STA) belonging to a common cooperative group.

[0115] Fig. 18 is a diagram showing an example of NAV control operation according to Example 1 of Method 1. In the example shown in Fig. 18, AP1 (Sharing AP) and STA1 belong to BSS1, and AP2 (Shared AP) and STA2 belong to BSS2. Also, in the example shown in Fig. 18, AP1, AP2, STA1, and STA2 belong to a common cooperative group.

[0116] If the NAV control method defined in the above-mentioned 11ax is applied to the configuration example of the wireless communication system shown in Fig. 18, when STA1 and STA2 receive a signal (e.g., CTI, CTR, or CTAS) related to MAP coordination negotiation transmitted by AP1 and AP2, the received signal is not a signal addressed to STA1 and STA2, so they update their NAV (Intra-BSS NAV or Basic NAV). As a result, UL transmission (UL Tx) of STA1 and STA2 may be stopped.

[0117] In contrast, in Example 1 of Method 1, STA 200 determines whether to update the NAV depending on whether the received signal is transmitted from a terminal belonging to a common cooperative group.

[0118] For example, as shown in FIG. 18, STA1 and STA2 belong to a common cooperative group with AP1, so STA1 and STA2 do not update their NAVs even when they receive a MAP coordination negotiation signal (e.g., a CTI or CTAS addressed to AP2) sent from AP1.

[0119] Similarly, for example, as shown in FIG. 18, since STA1 and STA2 and AP2 belong to a common cooperative group, STA1 and STA2 do not update their NAV even when they receive a MAP coordination negotiation signal (e.g., a CTR addressed to AP1) sent from AP2.

[0120] Therefore, as shown in FIG. 18, after the MAP coordination negotiation, STA1 and STA2 are able to perform UL transmission when instructed to do so by the Trigger frame.

[0121] On the other hand, as shown in FIG. 18, a terminal (Other AP / STA) that does not belong to the common cooperative group with AP1 and AP2 sets Basic NAV when it receives a MAP coordination negotiation signal from AP1 or AP2.

[0122] In this way, in Example 1 of Method 1, STA 200 does not update its NAV when the source of the received signal belongs to the common cooperative group, and updates its NAV when the source of the received signal does not belong to the common cooperative group. This NAV control allows STA 200 to transmit a UL signal without being hindered by the NAV setting of a signal transmitted by AP 100 that belongs to the common cooperative group, for example.

[0123] In addition, when the STA 200 receives a signal different from a signal related to MAP coordination, even if the signal is a transmission signal from a terminal belonging to a cooperative group, the STA 200 may update the NAV. The STA 200 may distinguish between signals related to MAP coordination and signals different from the signals related to MAP coordination by, for example, an identifier (e.g., a BSSID or BSS color for non-cooperative transmission).

[0124] <Example 2 of Method 1> In Example 2 of Method 1, the AP 100 does not update the NAV when information about the TXOP is notified by a signal transmitted from a terminal (AP / STA) belonging to a common cooperative group.

[0125] Fig. 19 is a diagram showing an example of NAV control operation according to Example 2 of Method 1. In the example shown in Fig. 19, AP1 (Sharing AP) and STA1 belong to BSS1, and AP2 (Shared AP) and STA2 belong to BSS2. Also, in the example shown in Fig. 19, AP1, AP2, STA1, and STA2 belong to a common cooperative group.

[0126] 19, for example, the TXOP acquired by AP1 (Sharing AP) may be divided into multiple TXOPs (for example, TXOP1, TXOP2, and TXOP3) based on the timing of UL transmission of each STA, as in Fig. 8. Therefore, for example, even when Basic NAV is set as in STA2 shown in Fig. 19, UL transmission instructed by the Trigger frame from AP2 is possible.

[0127] 19 , if the NAV control method defined in the 11ax standard described above is applied, when AP2 receives a trigger frame addressed to STA1 from AP1, for example, the received signal is not addressed to AP2, and so the AP2 updates (or sets) the basic NAV. As a result, there is a possibility that transmission of the trigger frame addressed to STA2 from AP2 will be stopped.

[0128] In contrast, in Example 2 of Method 1, the AP 100 determines whether to update the NAV depending on whether the received signal is transmitted from a terminal that belongs to a common cooperative group.

[0129] For example, as shown in FIG. 19, since AP2 and AP1 belong to a common cooperative group, AP2 does not update its NAV even when it receives a Trigger frame sent from AP1 to STA1.

[0130] In this way, in Example 2 of Method 1, the AP 100 does not update the NAV when the source of the received signal belongs to the common cooperative group, but updates the NAV when the source of the received signal does not belong to the common cooperative group. This NAV control enables the AP 100 to perform cooperative transmission without being hindered by the NAV setting of the transmission signal of another AP 100 that belongs to the common cooperative group, for example.

[0131] In addition, the AP 100 may update the NAV when it receives a signal different from a signal related to MAP coordination, even if the signal is a transmission signal from a terminal belonging to a cooperative group. The AP 100 may distinguish between signals related to MAP coordination and signals different from the signals related to MAP coordination by, for example, an identifier (for example, a BSSID or BSS color for non-cooperative transmission).

[0132] Method 1 has been described above.

[0133] For example, in Example 1 of Method 1 ( FIG. 18 ), an example of the operation of STA 200 has been described, but in Example 1 of Method 1, AP 100 may not update its NAV when information about TXOP is notified by a signal transmitted from a terminal (AP / STA) belonging to a common cooperative group, as in Example 2. For example, in FIG. 18 , AP 2 may not update its NAV when it receives a Trigger frame addressed to STA 1 from AP 1.

[0134] [Method 2] In Method 2, for example, when a terminal (AP / STA) receives a signal including information about TXOP from another terminal belonging to a common cooperative group (in other words, when notified), it updates its Intra-BSS NAV.

[0135] Furthermore, in method 2, when the user information of a signal (e.g., a Trigger frame) transmitted from another terminal belonging to the common cooperative group includes an identifier (e.g., an AID) of the terminal (the terminal itself), the terminal may respond without considering the Intra-BSS NAV. For example, when the user information of a signal transmitted from another terminal belonging to the common cooperative group includes an identifier of the terminal, the terminal may transmit a UL signal, ignoring the Intra-BSS NAV.

[0136] Fig. 20 is a diagram showing an example of the operation of NAV control according to Method 2. In the example shown in Fig. 20, AP1 (Sharing AP) and STA1 belong to BSS1, and AP2 (Shared AP) and STA2 belong to BSS2. Also, in the example shown in Fig. 20, AP1, AP2, STA1, and STA2 belong to a common cooperative group. Also, in the example shown in Fig. 20, AP3 and STA3 do not belong to a common cooperative group with AP1, AP2, STA1, and STA2.

[0137] If the NAV control method defined in the 11ax standard described above is applied to the exemplary configuration of the wireless communication system shown in Fig. 20, STA1 updates the Intra-BSS NAV by, for example, a signal from AP1 to AP2 (e.g., CTI, CTAS), and updates the Basic NAV by a signal from AP2 to AP1 (e.g., CTR). Similarly, if the NAV control method defined in the 11ax standard described above is applied, STA2 updates the Basic NAV by, for example, a signal from AP1 to AP2 (e.g., CTI, CTAS), and updates the Intra-BSS NAV by a signal from AP2 to AP1 (e.g., CTR).

[0138] Thus, for example, in the 11ax NAV control method, STA1 updates its Basic NAV based on a signal from AP2, and STA2 updates its Basic NAV based on a signal from AP1, so there is a possibility that they will stop transmitting UL signals instructed by a Trigger frame from an AP belonging to a common BSS.

[0139] In contrast, in Method 2, the terminals (AP / STA) update the Intra-BSS NAV when a TXOP is notified by a signal transmitted from a terminal belonging to a common cooperative group. For example, as shown in Fig. 20, when STA1 and STA2 receive signals addressed to other terminals from AP1 and AP2, they may update the Intra-BSS NAV regardless of the BSS to which they belong (in other words, not Basic NAV) if the source terminal belongs to the common cooperative group.

[0140] Also, in method 2, for example, in the example shown in FIG. 20 , when STA1 is instructed to transmit an UL signal by a Trigger frame transmitted from AP1 belonging to a common cooperative group, STA1 may set the Intra-BSS NAV counter to 0 (in other words, reset) and perform UL transmission.

[0141] 20, like STA1, when instructed to perform UL transmission by a Trigger frame transmitted from AP2 belonging to the common cooperative group, STA2 sets its Intra-BSS NAV counter to 0. However, as shown in FIG. 20, even when the Intra-BSS NAV counter in STA2 is set to 0, Basic NAV is set in STA2 by a transmission signal from another terminal (e.g., AP3) that does not belong to the common cooperative group, and therefore STA2 stops UL transmission.

[0142] 20 has described a case in which the STA 200 sets the Intra-BSS NAV counter to 0 when instructed (requested) to transmit an UL signal by a Trigger frame transmitted from an AP 100 belonging to a common cooperative group, but this is not limiting. For example, as shown in FIG. 21 , when the STA 200 is instructed to transmit an UL signal by a Trigger frame transmitted from an AP 100 belonging to a common cooperative group, the STA 200 may transmit an UL signal without considering (for example, ignoring) the Intra-BSS NAV for a certain period of time (for example, the length of the signal transmitted in response to the Trigger frame, or the time resource notified by the Trigger frame). For example, the STA 200 may decrement the Intra-BSS NAV counter according to the elapsed time even during the period in which the Intra-BSS NAV is not considered.

[0143] Thus, in Method 2, STA 200 may set Intra-BSS NAV (e.g., a transmission prohibition period for a common BSS) when receiving a signal including information about TXOP from a source belonging to a common cooperative group. Also, STA 200 may set Basic NAV (e.g., a transmission prohibition period for a common BSS) when receiving a signal including information about TXOP from a source not belonging to the common cooperative group.

[0144] Furthermore, STA 200 may cancel the Intra-BSS NAV setting when receiving a Trigger frame including user information addressed to STA 200. In other words, STA 200 does not need to cancel the Basic NAV setting even when receiving a Trigger frame including user information addressed to STA 200.

[0145] Therefore, the AP 100 may notify, for example, terminals belonging to a common cooperative group of information related to Intra-BSS NAV, thereby canceling only the Intra-BSS NAV for the STAs 200 participating in the cooperative transmission (the STAs 200 in the cooperative group), thereby enabling the STAs 200 to transmit UL signals.

[0146] Furthermore, in method 2, for example, by not canceling the Intra-BSS NAV of STA 200 that does not participate in the coordinated transmission (e.g., STA 200 outside the coordinated group), UL transmission of STA 200 that does not participate in the coordinated transmission can be suppressed. Also, for example, by canceling the Intra-BSS NAV of STA 200 that belongs to the common coordinated group and not canceling the Basic NAV by a transmission signal from a terminal that does not belong to the common coordinated group, UL transmission of STA 200 that does not belong to the common coordinated group can be suppressed. Therefore, according to method 2, contention in MAP coordination can be suppressed.

[0147] <Method 2-1> In method 2-1, AP 100 may include control information in a transmission signal notifying that transmission will be performed without considering (ignoring) the Intra-BSS NAV notified by terminals belonging to the common cooperative group. STA 200 may receive, for example, control information notifying that transmission will be performed while ignoring the Intra-BSS NAV (for example, information regarding the cancellation of the Intra-BSS NAV setting corresponding to the common cooperative group), and cancel the Intra-BSS NAV setting based on the received information.

[0148] FIG. 22 is a diagram showing an example of a transmission signal (for example, a Trigger frame) including control information indicating transmission without considering Intra-BSS NAV.

[0149] As shown in Fig. 22, control information (e.g., "ignore NAV" subfield) indicating transmission that does not take the Intra-BSS NAV into consideration (transmission that ignores the Intra-BSS NAV) may be included in the user information of the Trigger frame. For example, when ignore NAV = 1, the STA 200 may cancel or temporarily ignore the Intra-BSS NAV and transmit a TB PPDU. For example, the period during which the Intra-BSS NAV is ignored may be notified to the STA 200 by the UL Length subfield of the Common field of the Trigger frame.

[0150] On the other hand, for example, if ignore NAV=0, STA 200 does not need to ignore Intra-BSS NAV.

[0151] In this way, with method 2-1, for example, AP 100 can notify STA 200 individually whether or not to apply Intra-BSS NAV ignorance, thereby enabling a specific STA 200 to ignore Intra-BSS NAV and transmit a UL signal, and can also notify other terminals whether or not each STA 200 ignores Intra-BSS NAV.

[0152] An example of a NAV control method in MAP coordination has been described above.

[0153] Thus, in this embodiment, AP 100 and STA 200 may control NAV differently depending on whether the received signal is a signal transmitted from a terminal (e.g., AP / STA) belonging to a common cooperative group.

[0154] For example, as in method 1, in a common cooperative group, each terminal does not need to update (set) its NAV even when it receives a signal addressed to another terminal. This prevents the AP 100 belonging to the cooperative group from being unable to transmit a Trigger frame, for example, in MAP coordination. Furthermore, the STA 200 can prevent itself from being unable to perform UL transmission when it receives a Trigger frame. Therefore, according to this embodiment, it is possible to avoid cooperative transmission in MAP coordination being hindered by the NAV.

[0155] Furthermore, for example, as in Method 2, terminals (APs / STAs) belonging to a common cooperative group may update their Intra-BSS NAV without updating their Basic NAV based on signals related to the common cooperative group. This allows, for example, a rule to ignore NAV to be applied only to terminals belonging to the common cooperative group, thereby avoiding conflicts caused by rules to ignore the set NAV.

[0156] As such, according to this embodiment, in MAP coordination, NAV control can be prevented from interfering with AP / STA transmission and reception, and cooperative communication in MAP coordination can be carried out appropriately, thereby improving the communication efficiency of cooperative communication in MAP coordination.

[0157] One embodiment of the present disclosure has been described above.

[0158] (Other Embodiments) (1) In the above-described embodiment, an example was described in which STA 200 transmits a UL signal in CTDMA of MAP coordination, but the coordination method is not limited to CTDMA and may be another method.

[0159] (2) Example 2 of Method 1 may be applied in combination with Method 2. For example, as shown in Fig. 19, when AP 100 receives a signal addressed to another terminal from a terminal belonging to the common cooperative group, AP 100 may not update the NAV. Also, for example, when STA 200 receives a signal addressed to another terminal from a terminal belonging to the common cooperative group, STA 200 may update the Intra-BSS NAV, and when STA 200 receives a Trigger frame instructing the transmission of an UL signal, STA 200 may ignore (e.g., temporarily ignore) the Intra-BSS NAV.

[0160] (3) In the above-described embodiment, Method 1 and Method 2 illustrate an example in which negotiation between APs 100 (e.g., Tx Indication and Request phase and Schedule Allocation phase) and coordinated transmission (Data Tx phase) are performed within one TXOP, as shown in Fig. 1 , but this is not limiting. For example, a non-limiting example of the present disclosure may be applied to MAP coordination using multiple TXOPs.

[0161] For example, three stages of MAP coordination processing may be performed across multiple TXOPs as shown in Fig. 23. In the example shown in Fig. 23, in the first TXOP, the Tx Indication and Request phase may be performed to determine the APs 100 that will participate in MAP coordination, and in the second TXOP, the Schedule Allocation phase and the Data Tx phase may be performed.

[0162] The number of TXOPs and the combination of processes performed in each TXOP shown in FIG. 23 are merely examples and are not limiting.

[0163] (4) Methods 1 and 2 of the above-described embodiments may be applied to MAP sounding.

[0164] MAP sounding is a method of cooperatively acquiring channel information by cooperative sounding between APs 100. Examples of cooperative sounding between APs 100 include sequential sounding as shown in Fig. 24 and joint sounding as shown in Fig. 25.

[0165] 24 and 25, STA1 is a sharing AP belonging to AP1, which is a sharing AP, and STA2 is a shred STA belonging to AP2, which is a shared AP. For example, in sequential sounding as shown in Fig. 24, AP2 updates Basic NAV by TXOP notified by Null Data Packet Announcement (NDPA) from AP1. Therefore, in AP2, Basic NAV may stop transmission of NDPA.

[0166] In this case, for example, as in Example 2 of Method 1, AP2 can achieve sequential sounding (e.g., transmission of signals such as NDPA) by not updating the Basic NAV in response to a TXOP notified by NDPA from AP1 belonging to a common cooperative transmission group.

[0167] The timing of MAP sounding is not limited.

[0168] For example, as shown in FIG. 26, multi-AP sounding may be performed before APs 100 negotiate with each other to determine whether or not to participate in MAP coordination, and channel information that may be used for MAP coordination may be obtained in advance.

[0169] Also, for example, as shown in FIG. 27, after determining whether or not to participate in MAP coordination through negotiation between APs 100, Multi-AP sounding may be performed and channel information to be used for coordinated transmission may be acquired.

[0170] (5) In Method 2, a method for notifying temporary ignorance of Intra-BSS NAV has been described, but the method for notifying temporary ignorance of Intra-BSS NAV is not limited to notification by control information.

[0171] For example, the AP 100 may instruct the order of the STAs 200 that will ignore the Intra-BSS NAV based on the transmission order (or arrangement order) of the user information in the Trigger frame. For example, as shown in Fig. 28, when a Trigger frame includes multiple pieces of user information, the STA 200 that is instructed by the first User Info #1 may ignore the Intra-BSS NAV and transmit a UL signal after a specified time (for example, a Short Inter Frame Space (SIFS)) has elapsed since receiving the Trigger frame.

[0172] Similarly, STA 200 indicated by the Mth user information (where M is an integer greater than 1 and equal to or less than N, the maximum value of the user information) grasps the STA ID included in the M-1th user information. For example, when STA 200 indicated by the Mth user information detects the STA ID of the M-1th user information from the received signal (i.e., when it receives a signal from the M-1th STA), it may transmit a UL signal after a SIFS.

[0173] The period for ignoring Intra-BSS NAV for multiple STAs 200 whose user information is included in the Trigger frame may be notified, for example, in the common information of the Trigger frame (for example, the UL Length subfield of Common Info).

[0174] Fig. 29 is a diagram showing an example of operation in which the order in which ignore NAV is applied is notified based on the transmission order of user information. As shown in Fig. 29, STA1, which is indicated by the user information at the beginning of the Trigger frame, transmits a UL signal SIFS after receiving the Trigger frame. Also, as shown in Fig. 29, STA2, which is indicated by the user information at the second position in the Trigger frame, transmits a UL signal SIFS after receiving the UL signal of STA1.

[0175] (6) In Method 2, the period during which Intra-BSS NAV is ignored for multiple STAs 200 may be notified by the common information of the Trigger frame. For example, the period during which Intra-BSS NAV is ignored may be set commonly for multiple STAs 200. In this case, the time length of ignore NAV may be notified in the common information of the Trigger frame (for example, the UL Length subfield of Common Info).

[0176] For example, as shown in Fig. 30, AP1 notifies each STA (STA1 and STA2) of the ignore NAV period (e.g., T [us]) in the UL Length subfield of the Trigger frame. STA1 may transmit a UL signal with a length of T [us] SIFS after receiving the Trigger frame. STA2 may transmit a UL signal with a length of T [us] SIFS+T [us] after receiving the Trigger frame.

[0177] (7) In method 2-1, the AP 100 may notify the STA 200 of the ignore NAV time allocation information individually using the user information of the Trigger frame. For example, as shown in Fig. 31 , the AP 100 may notify the ignore NAV length subfield using the Trigger Dependent User Info of the user information.

[0178] For example, as shown in Fig. 32, AP1 may notify each STA of individual ignore NAV time allocation information in User Info corresponding to each STA1 and STA2. For example, as shown in Fig. 32, STA1 may transmit a T1 [us] long UL signal SIFS after receiving the Trigger frame. Also, STA2 may transmit a T2 [us] long UL signal SIFS+T1 [us]+SIFS after receiving the Trigger frame.

[0179] (8) In Method 2-1, we described a method in which control information (ignore NAV subfield) notifying that the Intra-BSS NAV will be temporarily ignored and transmitted is included in the user information of the Trigger frame, but this is not limited to this and the notification may be made using other user information.

[0180] For example, as shown in FIG. 33, ignore NAV may be notified using a reserved subfield included in the user information (User field) of the EHT-SIG.

[0181] Also, for example, as shown in FIG. 34, ignore NAV may be notified using a reserved subfield included in the user information (STA Info field) of the NDPA.

[0182] Furthermore, the information used to notify the ignore NAV is not limited to user information. For example, the ignore NAV may be notified in common information. FIG. 35 is a diagram showing an example of notifying the ignore NAV by including it in the common information. As shown in FIG. 35, the ignore NAV may be notified using the Disregard subfield included in the U-SIG. When the ignore NAV is notified in the common information, the terminal may, for example, control the NAV for each BSS. For example, when ignore NAV=1, a terminal of a BSS having a BSS color common to the BSS color notified by the BSS color subfield of the U-SIG may temporarily ignore the Intra-BSS NAV and transmit.

[0183] (9) Methods 1 and 2 are not limited to application to MAP coordination. For example, methods 1 and 2 may be applied to Triggered TXOP Sharing.

[0184] Triggered TXOP Sharing is a transmission method in which the AP 100 allocates a portion of the acquired TXOPs to the STA 200 using a Multi-User (MU)-RTS TXOP Sharing (TXS) Trigger frame. In addition, Triggered TXOP Sharing can switch between two communication methods depending on the value of the TXOP Sharing Mode subfield included in the MU-RTS TXS Trigger frame.

[0185] The first communication method is a method in which, when TXOP Sharing Mode = 1 is notified in the MU-RTS TXS Trigger frame, STA 200 performs UL transmission to the AP 100 to which it belongs during the TXOP allocated to STA 200.

[0186] The second communication method is a method in which, when TXOP Sharing mode = 2 is notified in the MU-RTS TXS Trigger frame, STA200 transmits with the AP100 to which it belongs or with other STAs during the TXOP allocated to STA200.

[0187] Furthermore, Triggered TXOP Sharing is not performed when TXOP Sharing Mode = 0. Furthermore, a control signal (e.g., CTLS in FIG. 2 ) used by the AP 100 to notify the STA 200 of scheduling information may be notified using an MU-RTS Trigger frame or an MU-RTS TXS Trigger frame.

[0188] Fig. 36 is a diagram showing an example in which Method 2 is applied when TXOP Sharing Mode = 1. In the example shown in Fig. 36, AP1 and STA1 belong to a common cooperative group.

[0189] 36, AP1 notifies other terminals of a TXOP by transmitting a CTS signal (called CTS-to-self) that includes the address of AP1 in the destination information. When STA1 receives the CTS-to-self signal from AP1, it updates its Intra-BSS NAV.

[0190] Next, AP1 transmits an MU-RTS TXS Trigger frame including TXOP Sharing Mode = 1 to STA1 and allocates a TXOP to STA1. When the NAV control method defined in the IEEE 802.11ax described above is applied, STA1 may stop transmission from STA1 to AP1 due to the Intra-BSS NAV notified by AP1. In contrast, when Method 2 is applied, if STA1 is notified of Triggered TXOP Sharing by AP1, which is a member of a common cooperative group, STA1 may temporarily ignore the Intra-BSS NAV for the time resource notified by the MU-RTS TXS Trigger frame. For example, STA1 may transmit a CTS signal to AP1 in response to the MU-RTS TXS Trigger frame, and then transmit a Data signal to AP1 using a PPDU other than a TB PPDU.

[0191] Fig. 37 is a diagram showing an example in which Method 2 is applied when TXOP Sharing Mode = 2. In the example shown in Fig. 37, AP1, STA1, and STA2 belong to a common cooperative group.

[0192] 37, AP1 notifies STA1 and STA2 of TXOP by transmitting a CTS-to-self signal. Upon receiving the CTS-to-self signal from AP1, STA1 and STA2 update their Intra-BSS NAV.

[0193] Next, AP1 transmits an MU-RTS TXS Trigger frame including TXOP Sharing Mode = 2 to STA1 and allocates a TXOP to STA1. When the NAV control method defined in 11ax described above is applied, STA1 may stop transmission from STA1 to AP1 or STA2 due to the Intra-BSS NAV notified by AP1. Similarly, STA2 may stop transmission from STA2 to STA1 due to the Intra-BSS NAV notified by AP1. In contrast, when method 2 is applied, if STA1 is notified of Triggered TXOP Sharing by AP1, which is a member of a common cooperative group, STA1 may temporarily ignore the Intra-BSS NAV during the time resource notified by the MU-RTS TXS Trigger frame.

[0194] For example, STA1 may transmit a CTS signal to AP1 in response to the MU-RTS TXS Trigger frame, and then transmit a Data signal to another STA (eg, STA2) in a PPDU that is not a TB PPDU.

[0195] Also, as shown in FIG. 37, STA2 that receives a Data signal from STA1, which is in a common cooperative group, may temporarily ignore the Intra-BSS NAV in order to transmit an Ack signal in response to the Data signal.

[0196] (10) The values ​​such as the number of APs, the number of STAs, and the number of BSSs used in the above-described embodiment are merely examples and are not limiting, and other values ​​may be set.

[0197] Furthermore, in the above embodiment, a configuration example based on the 11ax frame format has been described as an example, but the format to which an embodiment of the present disclosure is applied is not limited to the 11ax format.

[0198] Furthermore, in the above embodiment, the operation in UL communication has been described, but an embodiment of the present disclosure is not limited to UL communication and may be applied to, for example, DL communication or sidelink.

[0199] Furthermore, the frame configurations (e.g., formats) described in the above embodiments are merely examples, and are not limited to these, and other configurations may be used. For example, in these frame configurations, some fields may not be set, and other fields may be set.

[0200] (11) Information indicating whether STA200 supports the functions, operations, or processing described in the above-mentioned embodiments may be transmitted (or notified) from STA200 to AP100, for example, as capability information or capability parameters of STA200.

[0201] The capability information may include an information element (IE) that individually indicates whether the STA 200 supports at least one of the functions, operations, or processes described in each of the above-described embodiments. Alternatively, the capability information may include an information element that indicates whether the STA 200 supports a combination of any two or more of the functions, operations, or processes described in each of the above-described embodiments. An information element may also be simply referred to as an element.

[0202] For example, based on the capability information received from the STA 200, the AP 100 may determine (or decide or assume) the functions, operations, or processes that the STA 200 that transmitted the capability information supports (or does not support). The AP 100 may perform operations, processes, or controls according to the determination result based on the capability information. For example, the AP 100 may control MAP coordination based on the capability information received from the STA 200.

[0203] Note that the fact that the STA 200 does not support some of the functions, operations, or processes described in the above-described embodiments may be interpreted as meaning that such some of the functions, operations, or processes are restricted in the STA 200. For example, information or a request regarding such restrictions may be notified to the AP 100.

[0204] Information regarding the capabilities or limitations of STA200 may, for example, be defined in a standard, or may be implicitly notified to AP100 in association with information known at AP100 or information sent to AP100.

[0205] (12) 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 referred to as an IC, system LSI, super LSI, or ultra LSI.

[0206] 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.

[0207] 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.

[0208] 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.

[0209] 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.

[0210] 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.

[0211] 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.

[0212] 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.

[0213] A communication device according to one embodiment of the present disclosure is a communication device comprising a receiving circuit that receives a signal, and a control circuit that changes settings related to a transmission prohibition period depending on whether the sender of the signal belongs to a group related to cooperative communication that is common to the communication device.

[0214] In one embodiment of the present disclosure, the control circuit determines whether the source belongs to the group based on identification information included in the signal.

[0215] In one embodiment of the present disclosure, the control circuit determines that the sender belongs to the group if the signal contains user information addressed to the communication device.

[0216] In one embodiment of the present disclosure, the control circuit determines whether the sender belongs to the group based on information about the group included in the beacon signal.

[0217] In one embodiment of the present disclosure, the communication device is a station (STA), and the control circuit does not set the transmission prohibition period when it receives the signal including information regarding a transmission opportunity from the source belonging to the group.

[0218] In one embodiment of the present disclosure, the communication device is an access point, and the control circuit does not set the transmission prohibition period when it receives the signal including information regarding a transmission opportunity from the source belonging to the group.

[0219] In one embodiment of the present disclosure, when the control circuit receives the signal including information regarding a transmission opportunity from the source belonging to the group, it sets a first transmission prohibition period for a Basic Service Set (BSS) common to the communication device, and when the control circuit receives the signal including information regarding the transmission opportunity from the source not belonging to the group, it sets a second transmission prohibition period for a BSS different from that of the communication device.

[0220] In an embodiment of the present disclosure, the control circuit cancels the setting of the first transmission inhibit period when a trigger frame including user information addressed to the communication device is received.

[0221] In one embodiment of the present disclosure, the communication device further includes a receiving circuit that receives information regarding cancellation of the setting of the first transmission inhibit period, and the control circuit cancels the setting of the first transmission inhibit period based on the information.

[0222] In a communication method according to one embodiment of the present disclosure, a communication device receives a signal and changes settings related to a transmission prohibition period depending on whether the sender of the signal belongs to a group related to cooperative communication that is common to the communication device.

[0223] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2021-128430, filed on August 4, 2021, are incorporated herein by reference in their entirety.

[0224] One embodiment of the present disclosure is useful in wireless communication systems.

[0225] 100 AP 101, 201 Radio receiving unit 102 Preamble demodulation unit 103 Data demodulation unit 104 Data decoding unit 105, 205 NAV control unit 106 Scheduling unit 107 Data generation unit 108 Data encoding unit 109 Data modulation unit 110 Preamble generation unit 111, 207 Radio transmitting unit 200 STA 202 Preamble demodulation unit 203 Data demodulation unit 204 Data decoding unit 206 Transmission signal generation unit

Claims

1. A communication device comprising: a receiving circuit that receives a signal; and a control circuit that changes settings related to a transmission prohibition period depending on whether the sender of the signal belongs to a group related to cooperative communication common to the communication device.

2. The communication device according to claim 1, wherein the control circuit determines whether the sender belongs to the group based on identification information included in the signal.

3. The communication device according to claim 1, wherein said control circuit determines that said sender belongs to said group when said signal contains user information addressed to said communication device.

4. The communication device according to claim 1, wherein the control circuit determines whether the sender belongs to the group based on information about the group contained in a beacon signal.

5. The communication device according to claim 1, wherein the communication device is a station (STA), and the control circuit does not set the transmission prohibition period when the control circuit receives the signal including information regarding a transmission opportunity from the source belonging to the group.

6. The communication device according to claim 1, wherein the communication device is an access point, and the control circuit does not set the transmission prohibition period when the control circuit receives the signal including information about a transmission opportunity from the source belonging to the group.

7. The communication device of claim 1, wherein the control circuit, when receiving the signal including information regarding a transmission opportunity from the source belonging to the group, sets a first transmission prohibition period for a Basic Service Set (BSS) common to the communication device, and when receiving the signal including information regarding the transmission opportunity from the source not belonging to the group, sets a second transmission prohibition period for a BSS different from that of the communication device.

8. The communication device according to claim 7, wherein the control circuit cancels the setting of the first transmission inhibit period when a trigger frame including user information addressed to the communication device is received.

9. The communication device according to claim 7, further comprising a receiving circuit that receives information relating to the cancellation of the setting of said first transmission prohibition period, and said control circuit cancels the setting of said first transmission prohibition period based on said information.

10. A communication method, comprising: a communication device receiving a signal; and varying a setting related to a transmission prohibition period depending on whether a sender of the signal belongs to a group related to cooperative communication common to the communication device and the communication device.

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