Access point and communication method

Abstract

The present invention improves the efficiency of a transmission control in wireless communication. This access point comprises: a control circuit that, when the type of cooperative communication is a first type, configures parameters pertaining to the cooperative communication for a plurality of access points, which perform the cooperative communication, in a field of a control signal in which information common to the plurality of access points is stored; and a transmission circuit that transmits the control signal.

Description

Access point and communication method

[0001] This disclosure relates to access points and communication methods.

[0002] The Institute of Electrical and Electronics Engineers (IEEE) is working on standardizing wireless communication standards such as wireless LAN (Local Area Network; also known as WLAN).

[0003] The IEEE 802.11 Working Group is considering Multi-AP (MAP) coordination, in which multiple access points (also called Access Points (APs) or base stations) cooperate to transmit data (for example, Multi-AP coordinated communication or coordinated communication) (see, for example, Non-Patent Documents 1, 4, 5, and 6).

[0004] Multi-AP cooperative communication includes types (types or schemes) such as "Coordinated Spatial Reuse (Co-SR)," which reduces interference to the destination STA of other APs by controlling the transmit power; "Coordinated Beamforming (Co-BF)," which reduces interference to the destination STA of other APs by null control; "Coordinated Time Division Multiple Access (Co-TDMA)," which divides and shares time resources; and "Joint Transmission (JT)," where multiple APs transmit the same data. Note that Co-SR, Co-BF, and Co-TDMA may also be written as C-SR, C-BF, and C-TDMA, respectively.

[0005] IEEE 802.11-24 / 209r6IEEE P802.11be / D7.0IEEE 802.11-24 / 1507r3, UHR Trigger Frame DesignIEEE 802.11-23 / 0079r10, IEEE 802.11 UHR Proposed CSDIEEE 802.11-23 / 1871r5, M-AP Coordination Transmission frameworkIEEE 802.11-20 / 0410r4, Coordinated Spatial Reuse Procedure

[0006] However, methods for controlling multi-AP coordination in wireless communication such as Wi-Fi have not been sufficiently studied.

[0007] Non-limiting embodiments of this disclosure contribute to providing access points, terminals, and communication methods that can improve the efficiency of transmission control in wireless communication.

[0008] An access point according to one embodiment of the present disclosure comprises a control circuit that sets parameters relating to the cooperative communication for a plurality of access points performing the cooperative communication in a field of the control signal in which information common to the plurality of access points is stored, when the type of cooperative communication is of type 1, and a transmission circuit that transmits the control signal.

[0009] These comprehensive or specific embodiments may be implemented as systems, devices, methods, integrated circuits, computer programs, or recording media, or as any combination of systems, devices, methods, integrated circuits, computer programs, and recording media.

[0010] According to one embodiment of the present disclosure, for example, the efficiency of transmission control in wireless communication can be improved.

[0011] Further advantages and effects of one embodiment of this disclosure will be made apparent from the specification and drawings. Such advantages and / or effects are provided by several embodiments and features described in the specification and drawings, but not all of them are necessarily provided in order to obtain one or more identical features.

[0012] Figures illustrating the operation of Multi-Access Point (Multi-AP) coordination, the operation of Multi-AP coordinated communication, the sequence of Multi-AP coordinated communication, a block diagram showing a partial configuration example of an AP (Access Point), a block diagram showing a partial configuration example of a terminal (STA: Station), a block diagram showing an AP configuration example, a block diagram showing an STA configuration example, a sequence of Multi-AP coordinated communication, a sequence of Multi-AP coordinated communication, an example of trigger frame format, an example of Common Info field format, an example of Special User Info field format, an example of frame format, an example of frame format, an example of communication parameters per bandwidth, an example of frame format, an example of bandwidth allocation, an example of frame format, an example of frame format, an example of frame format, an example of frame format, an example of frame format, an example of frame format, an example of frame format, an example of frame format.

[0013] Each embodiment of this disclosure will be described in detail below with reference to the drawings.

[0014] The IEEE 802.11 Working Group is working on the technical specifications for IEEE 802.11bn (hereinafter referred to as "11bn"), a standard that is backward compatible with IEEE 802.11be (hereinafter referred to as "11be"), a modified version of IEEE 802.11. 11be is also known as "Extremely High Throughput (EHT)," while 11bn is also known as "Ultra High Reliability (UHR)."

[0015] However, in multi-AP cooperative communication, the method for notifying control information to multiple wireless communication devices (for example, also called nodes), including APs and terminals (STAs: Stations, or non-AP STAs), has not been sufficiently considered.

[0016] In a non-limiting embodiment of the present disclosure, a method for appropriately controlling Multi-AP cooperative communication by a plurality of APs and improving the efficiency of Multi-AP cooperative communication will be described.

[0017] For example, in one embodiment of the present disclosure, an AP determines common parameters for some or all of one or more other APs performing Multi-AP cooperative communication, and transmits a control signal including the common parameters to the other APs. Thus, according to one embodiment of the present disclosure, the communication efficiency in Multi-AP cooperative communication can be improved.

[0018] [Configuration of Wireless Communication System] A wireless communication system according to an embodiment of the present disclosure may include, for example, an AP 100 and a STA 200. In the wireless communication system, there may be two or more APs 100 and one or more STAs 200. For example, the AP 100 transmits a downlink (DL) signal to another AP or the STA 200. Also, the STA 200 transmits an uplink (UL) signal based on the signal received from the AP 100.

[0019] For example, the wireless communication system may include the configuration shown in FIG. 1. In the example shown in FIG. 1, the wireless communication system includes AP1, AP2, STA1, and STA2. AP1 and AP2 operate Basic Service Set 1 (BSS1) and BSS2, respectively. BSS1 and BSS2 are also referred to as the BSS of AP1 and the BSS of AP2, respectively. STA1 and STA2 belong to BSS1 and BSS2, respectively (also referred to as associating with AP1 and AP2, respectively. Hereinafter, for convenience, it is referred to as belonging to AP1 and AP2). The arrows shown in FIG. 1 indicate a) the path (also called a wireless link) between AP1 and STA1, b) the path between AP2 and STA2, c) the path between AP1 and STA2, and d) the path between AP2 and STA1. In FIG. 1, AP1 and AP2 may cooperate in transmitting and receiving signals with STA1 and STA2.

[0020] Note that the number of APs 100 or BSSs included in the wireless communication system is not limited to two, and as shown in FIG. 2, there may be three or more (three in FIG. 2, i.e., AP1, AP2, and AP3). In FIG. 2, for example, AP1, AP2, and AP3 may cooperate in transmitting and receiving signals with STA1, STA2, and STA3.

[0021] In addition, each AP and STA described in each embodiment, the specification, and the drawings may each be a multi-link device (MLD). In that case, the AP may be read as an AP MLD, and the STA may be read as a non-AP MLD. Alternatively, the AP and STA may be an AP and an STA affiliated with an MLD, respectively.

[0022] FIG. 3 shows an example of a sequence of Multi-AP cooperative communication. As shown in FIG. 3, the Multi-AP cooperative communication sequence may include the following phases.

[0023] <Cooperative AP discovery phase> The cooperative AP discovery phase is a phase for preparing to control Multi-AP cooperative communication. For example, it is a phase in which an AP discovers other APs that support Multi-AP cooperative communication.

[0024] <Measurement Information Collection Phase> The measurement information collection phase is the period during which each node performs measurements, and it is the phase in which APs collect measurement information (hereinafter referred to as "measurement information" or "measurement report") from STAs under their control. For example, an STA receives transmitted signals from its own APs and non-affiliated APs (OBSS APs: Overlapped BSS APs, also called neighboring APs, etc.) (for example, beacon signals transmitted by APs during the cooperative AP discovery phase, etc.) and measures the signal quality. The signal quality of the affiliated APs and non-affiliated APs may include, for example, the received signal strength indicator (RSSI) from the affiliated APs, and interference power and signal error rate (Bit Error Rate (BER) or Packet Error Rate (PER)) from non-affiliated APs. An AP sends a signal to its affiliated STAs (STAs associated with the AP) requesting the transmission of measurement information, which includes information that can be derived based on the STA's reception and measurement results (e.g., values ​​obtained by measuring the received signal, information contained in the received signal) (e.g., path loss value with the AP, Signal Interference Noise Ratio (SINR) value per frequency resource, Acceptable Received Interference Level (ARIL) value, etc.). An STA that receives the measurement information transmission request signal transmits the measurement information to its affiliated AP. An AP may also notify other APs of the measurement information received from an STA, or exchange it with other APs. In the measurement information collection phase, an example has been described in which an STA receives a transmission signal from an AP and derives measurement information based on that received signal. However, an STA may also receive a transmission signal from an STA belonging to the same AP or an STA belonging to a different AP and derive measurement information based on that received signal. Furthermore, an AP may receive a transmission signal from another AP or STA and derive measurement information based on that received signal.Here, the operation of an STA or AP receiving a transmission signal from another STA or AP may occur during the measurement information acquisition phase, or it may occur before the measurement information acquisition phase. In addition, the STA may select the transmission signal of another AP relevant to the derivation of measurement information based on information about other APs notified by its own AP.

[0025] <Coordination Negotiation Phase> The coordination negotiation phase is the phase in which an AP negotiates with other APs (or other BSSs) whether or not it can participate in Multi-AP coordinated communication. For example, an AP that has acquired a channel use opportunity (Transmission Opportunity (TXOP)) (hereinafter also referred to as the "TXOP owner AP" or "Sharing AP") sends a signal (e.g., a Multi-AP request signal) containing candidate Multi-AP coordinated communication types and / or resource information to other APs that support Multi-AP coordinated communication. Other APs that receive the signal send a signal (e.g., a Multi-AP response signal) to the Sharing AP that contains whether or not it can participate in the Multi-AP coordinated communication notified by the signal. An AP that has notified that it can participate in Multi-AP coordinated communication receives control information regarding Multi-AP coordinated communication from the Sharing AP. APs that participate in Multi-AP coordinated communication are also called "Shared APs" or "Participating APs".

[0026] <Cooperative Signal Transmission Phase> The cooperative signal transmission phase is the phase in which APs perform Multi-AP cooperative communication. For example, a Sharing AP notifies a Shared AP of scheduling information including the type of Multi-AP cooperative communication (also called the "Multi-AP cooperative type") and allocated resource information. The signals transmitted in the cooperative signal transmission phase according to the scheduling information (for example, called the "Multi-AP cooperative communication signals") may be Downlink (DL) communication signals or Uplink (UL) communication signals.

[0027] The above describes an example of a multi-AP cooperative communication sequence.

[0028] Note that the Multi-AP cooperative communication sequence is not limited to the four phases shown in Figure 3. For example, in the Multi-AP cooperative communication sequence, AP 100 and STA 200 may perform the operations of the cooperative negotiation phase and the cooperative signal transmission phase shown in Figure 3 as a single phase. Also, AP 100 and STA 200 do not have to perform all of the operations of each phase shown in Figure 3. For example, AP 100 and STA 200 do not have to transmit and receive the Multi-AP request signal and Multi-AP response signal in the cooperative negotiation phase shown in Figure 3.

[0029] Figure 4 is a block diagram showing a partial configuration example of AP100 according to one embodiment of the present disclosure. In AP100 shown in Figure 4, when the type of cooperative communication (Multi-AP cooperative communication) is type 1, the control unit (corresponding to, for example, a control circuit) sets parameters related to cooperative communication for multiple APs (e.g., Shared APs) performing cooperative communication in an area of ​​the control signal where information common to multiple access points is stored. The communication unit (corresponding to, for example, a receiving circuit) transmits the control signal. AP100 also receives a control signal in which parameters related to cooperative communication for multiple access points performing cooperative communication are set in an area where information common to multiple access points is stored, when the type of cooperative communication (Multi-AP cooperative communication) is type 1. The control unit (corresponding to, for example, a control circuit) controls the cooperative communication based on the parameters.

[0030] Figure 5 is a block diagram showing a partial configuration example of STA200 according to one embodiment of the present disclosure. In the STA200 shown in Figure 5, the control unit (for example, corresponding to a control circuit) controls transmission or reception in cooperative communication, and the communication unit (for example, corresponding to a receiving circuit or a transmitting circuit) transmits or receives control information or data in cooperative communication.

[0031] (Embodiment 1) In this embodiment, multiple APs 100 and multiple STAs 200 perform Multi-AP cooperative communication. As an example, a method in which multiple APs 100 transmit and receive information related to Multi-AP cooperative communication with multiple STAs 200 and transmit Multi-AP cooperative communication signals will be described.

[0032] [Example of AP100 Configuration] Figure 6 is a block diagram showing an example of the configuration of AP100 according to this embodiment (for example, corresponding to a downlink wireless transmission device).

[0033] The AP100 shown in Figure 6 may include, for example, a wireless receiving unit 101, a preamble demodulation unit 102, a data demodulation unit 103, a data decoding unit 104, a Measurement information holding unit 105, a Buffer status information holding unit 106, a Capability information holding unit 107, a scheduling unit 108, a data generation unit 109, a data encoding unit 110, a data modulation unit 111, a preamble generation unit 112, and a wireless transmission unit 113.

[0034] Furthermore, at least one of the preamble demodulation unit 102, data demodulation unit 103, data decoding unit 104, Measurement information holding unit 105, Buffer status information holding unit 106, Capability information holding unit 107, scheduling unit 108, data generation unit 109, data encoding unit 110, data modulation unit 111, and preamble generation unit 112 shown in Figure 6 may be included in the control unit shown in Figure 4. Also, at least one of the wireless receiving unit 101 and wireless transmitting unit 113 shown in Figure 6 may be included in the communication unit shown in Figure 4.

[0035] In Figure 6, the wireless receiver 101 receives signals transmitted from other APs or STAs 200 (for example, downlink wireless receivers) via the antenna and performs wireless reception processing such as downconversion and analog-to-digital (A / D) conversion. The wireless receiver 101 divides the signal after wireless reception processing into a preamble section (also called a preamble signal) and a data section (also called a data signal), outputs the preamble signal to the preamble demodulation section 102, and outputs the data signal to the data demodulation section 103.

[0036] The preamble demodulation unit 102 performs a Fourier transform (e.g., Fast Fourier Transform (FFT)) on the preamble signal input from the wireless receiver unit 101 to extract reception control information used for demodulation and decoding of the data signal. The reception control information may include, for example, frequency bandwidth (BW), Modulation and Coding Scheme (MCS), and error correction code. The preamble demodulation unit 102 also performs channel estimation based on the reference signal included in the preamble signal and derives the channel estimate. The preamble demodulation unit 102 outputs the reception control information to the data demodulation unit 103 and the data decoding unit 104, and outputs the channel estimate to the data demodulation unit 103.

[0037] The data demodulation unit 103 performs an FFT on the data signal input from the wireless receiver unit 101 and demodulates the data signal using the reception control information and channel estimate input from the preamble demodulation unit 102. The data demodulation unit 103 outputs the demodulated data signal to the data decoding unit 104.

[0038] The data decoding unit 104 decodes the demodulated data signal input from the data demodulation unit 103 using the reception control information input from the preamble demodulation unit 102. The data decoding unit 104 checks for errors in the decoded data signal using a method such as Cyclic Redundancy Check (CRC). If there are no errors in the decoded data signal, the data decoding unit 104 outputs the decoded data signal to the Measurement information holding unit 105, the Buffer status information holding unit 106, the Capability information holding unit 107, and the scheduling unit 108.

[0039] The Measurement Information Holding Unit 105 holds measurement information received from other APs 100 or STAs 200, which is included in the decoded data signal input from the Data Decoding Unit 104, in a buffer. For example, the Measurement Information Holding Unit 105 may hold measurement information received from an STA 200 included in a BSS managed by AP 100 (e.g., BSS measurement information), and measurement information received from APs 100 and STAs 200 included in an OBSS (Overlapping BSS) managed by an AP different from AP 100 (e.g., OBSS measurement information). During scheduling, the Measurement Information Holding Unit 105 outputs the held measurement information to the Scheduling Unit 108.

[0040] The Buffer status information holding unit 106 holds Buffer status information (for example, Buffer status report (BSR)) of other APs or STAs 200 included in the decoded data signal input from the data decoding unit 104 in a buffer, and also outputs the Buffer status information to the scheduling unit 108.

[0041] The Capability Information Holding Unit 107 holds capability information of other APs or STAs 200 included in the decoded data signal input from the Data Decoding Unit 104 in a buffer, and also outputs the capability information to the Scheduling Unit 108. The capability information may include, for example, information indicating the Multi-AP cooperation type or subtype supported by each node (AP 100 or STA 200).

[0042] The scheduling unit 108 determines scheduling information for transmitting a signal to another AP or STA 200 (including, for example, destination information, MCS, error correction code, transmission power, parameters related to transmission power (e.g., transmission power of AP 100, allowable transmission power of other AP 100), and transmission / reception period). The scheduling unit 108 may determine the MCS, error correction code, and transmission power based on measurement information input from the Measurement information holding unit 105, for example. The scheduling unit 108 may also determine the destination information based on buffer status information input from the buffer status information holding unit 106 or capability information input from the capability information holding unit 107. The scheduling unit 108 outputs the scheduling information to the data generation unit 109, data encoding unit 110, data modulation unit 111, and preamble generation unit 112.

[0043] The data generation unit 109 generates a data sequence to be sent to another AP or STA 200 based on the scheduling information input from the scheduling unit 108. For example, the data sequence to be sent to another AP may include a Beacon signal containing capability information related to Multi-AP cooperation, a signal containing information requesting participation in Multi-AP cooperative communication (Multi-AP request signal), a signal containing information responding to participation in Multi-AP cooperative communication (Multi-AP response signal), or a signal containing Multi-AP cooperative communication scheduling information (Multi-AP Trigger signal). For example, the data sequence to be sent to STA 200 may include a signal requesting the transmission of measurement information (e.g., Measurement report poll signal, Beamforming Report Poll (BFRP) signal), a Buffer status report poll (BSRP) signal requesting the transmission of Buffer status information, or a DL signal transmitted via Multi-AP cooperative communication. The data generation unit 109 outputs the data sequence to the data encoding unit 110.

[0044] The data encoding unit 110 encodes the data sequence input from the data generation unit 109 based on the scheduling information input from the scheduling unit 108, and outputs the encoded data to the data modulation unit 111.

[0045] The data modulation unit 111 modulates the encoded data signal input from the data encoding unit 110 and performs an inverse Fourier transform (IFFT) based on the scheduling information input from the scheduling unit 108, and outputs the modulated data signal to the wireless transmission unit 113.

[0046] The preamble generation unit 112 generates a preamble signal based on scheduling information input from the scheduling unit 108. The preamble generation unit 112 modulates the preamble signal and performs IFFT processing, and outputs the preamble signal to the wireless transmission unit 113.

[0047] The wireless transmission unit 113 generates a wireless frame (also called a packet signal) by adding a preamble signal input from the preamble generation unit 112 to the modulated data signal input from the data modulation unit 111. The wireless transmission unit 113 performs wireless transmission processing such as digital-to-analog (D / A) conversion of the wireless frame and upconversion to the carrier frequency, and transmits the processed signal to another AP or STA 200 via the antenna.

[0048] [Example Configuration of STA200] Figure 7 is a block diagram showing an example configuration of STA200 (for example, a downlink wireless receiver).

[0049] The STA200 shown in Figure 7 may include, for example, a wireless receiving unit 201, a preamble demodulation unit 202, a data demodulation unit 203, a data decoding unit 204, a measurement control unit 205, a buffer status control unit 206, a transmission signal generation unit 207, and a wireless transmission unit 208.

[0050] Furthermore, at least one of the preamble demodulation unit 202, data demodulation unit 203, data decoding unit 204, Measurement control unit 205, Buffer status control unit 206, and transmission signal generation unit 207 shown in Figure 7 may be included in the control unit shown in Figure 5, and at least one of the wireless receiving unit 201 and wireless transmitting unit 208 shown in Figure 7 may be included in the communication unit shown in Figure 5.

[0051] In Figure 7, the wireless receiver 201 receives signals transmitted from the AP 100 (for example, a downlink wireless transmitter) via an antenna. The wireless receiver 201 performs wireless reception processing such as downconversion and A / D conversion of the received signal. The wireless receiver 201 outputs a preamble signal extracted from the received signal after wireless reception processing to the preamble demodulation unit 202, and outputs a data signal extracted from the received signal after wireless reception processing to the data demodulation unit 203.

[0052] The preamble demodulation unit 202 performs an FFT on the preamble signal input from the wireless receiver unit 201 to extract reception control information (e.g., including BW, MCS, and error correction codes) used for demodulation and decoding of the data signal (or data section). The preamble demodulation unit 202 also performs channel estimation based on the reference signal included in the preamble signal and derives the channel estimate. The preamble demodulation unit 202 outputs the reception control information to the data demodulation unit 203, the data decoding unit 204, and the Measurement control unit 205, and outputs the channel estimate to the data demodulation unit 203.

[0053] The data demodulation unit 203 performs an FFT on the data signal input from the wireless receiver unit 201, demodulates the data signal using the reception control information and channel estimate input from the preamble demodulation unit 202, and outputs the demodulated data signal to the data decoding unit 204.

[0054] The data decoding unit 204 uses the reception control information input from the preamble demodulation unit 202 to decode the demodulated data signal input from the data demodulation unit 203. The data decoding unit 204 performs error detection of the decoded data signal using, for example, a method such as CRC. If there are no errors in the decoded data signal, the data decoding unit 204 outputs the decoded data signal to the Measurement control unit 205, the Buffer status control unit 206, and the transmission signal generation unit 207.

[0055] The Measurement Control Unit 205 may, for example, calculate measurement information (e.g., BSS measurement information) based on signals received from AP100 and STA200 of the BSS to which STA200 belongs, and calculate measurement information (e.g., OBSS measurement information) based on signals received from AP100 and STA200 of a BSS to which STA200 does not belong. For example, in the case of signals transmitted from AP100 and STA200 within the BSS, the Measurement Control Unit 205 calculates measurement information (e.g., Channel State Information (CSI), Received Signal Strength Indicator (RSSI)) and stores it in a buffer. Also, in the case of signals transmitted from AP100 and STA200 within the OBSS, the Measurement Control Unit 205 calculates measurement information (e.g., CSI or interference power) and stores it in a buffer. Furthermore, the Measurement Control Unit 205 may use the calculated measurement information to calculate measurement information such as SINR or ARIL and store it in a buffer. The Measurement Control Unit 205 may store each calculated measurement information in a buffer, associating it with the signal identifier of the received signal from which the measurement information was calculated. The Measurement Control Unit 205 may also calculate measurement information for each frequency resource. When the Measurement Control Unit 205 receives a request to transmit measurement information in the decoded data signal input from the data decoding unit 204 (for example, when the decoded data signal is a BFRP signal), it outputs the measurement information held in the buffer to the transmission signal generation unit 207.

[0056] When the Buffer status control unit 206 receives a decoded data signal from the data decoding unit 204 that requests the transmission of UL transmission request information (e.g., Buffer status report) for the STA 200 (for example, when the decoded data signal is a BSRP signal), it outputs the UL transmission request information to the transmission signal generation unit 207.

[0057] The transmission signal generation unit 207 generates a data sequence to be transmitted to AP 100 based on the decoded data signal input from the data decoding unit 204. For example, the data sequence transmitted to AP 100 may include a response signal (ACK or Block ACK (BA)) to the signal received from AP 100. The transmission signal generation unit 207 may also include measurement information in the data sequence transmitted to AP 100 if the decoded data signal input from the data decoding unit 204 includes a signal requesting the transmission of Measurement information (e.g., a BFRP signal). The transmission signal generation unit 207 may also include UL transmission request information in the data sequence transmitted to AP 100 if the decoded data signal input from the data decoding unit 204 includes a signal requesting the transmission of Buffer status information (e.g., a BSRP signal). The transmission signal generation unit 207 generates a data signal by encoding the generated data sequence and performing modulation and IFFT processing on a predetermined frequency resource. The transmission signal generation unit 207 generates a wireless frame by adding a preamble signal to the data signal and outputs it to the wireless transmission unit 208.

[0058] The wireless transmission unit 208 performs wireless transmission processing, such as D / A conversion or upconversion to the carrier frequency, on the wireless frame input from the transmission signal generation unit 207, and transmits the processed signal to the AP 100 via the antenna.

[0059] The above describes the configuration examples of AP100 and STA200.

[0060] [Examples of AP100 and STA200 Operation] The following describes examples of operation related to Multi-AP cooperative communication in AP100 and STA200.

[0061] AP100 (for example, Sharing AP) may determine (or select, change) the type of transmitted frame and / or the format of the transmitted frame based on the Multi-AP cooperation type and / or the control method for each Multi-AP cooperation type (also called a subtype, option, etc.).

[0062] For example, Multi-AP coordination types include JT, C-SR, C-BF, and C-TDMA. Subtypes of C-SR include, for example, optimal coordination, rough one-way coordination, and complex one-way coordination. Optimal coordination is also called "full coordination," "two-way coordination," or "bi-directional coordination." One-way coordination is also called, for example, "half-coordination," "restricted coordination," or "uni-directional coordination." Rough one-way coordination is also called "simple one-way coordination." AP 100 may operate in a single subtype for a single Multi-AP coordination type, or it may operate in multiple subtypes (for example, selecting one subtype for each Multi-AP coordinated transmission).

[0063] For example, a Sharing AP may, in the measurement information collection phase, transmit measurement information to other APs and receive measurement information from other APs, and in the coordination negotiation phase, determine control information to be transmitted and received between multiple APs performing Multi-AP coordinated communication, and transmit or receive the determined control information. One example of this operation is the operation of Optimal coordination, a subtype of C-SR. Optimal coordination is a C-SR transmission control method in which a Shared AP aggregates measurement information collected from its subordinate STAs to a Sharing AP, and the Sharing AP determines the transmission power of each AP so as to reduce interference to the destination STA of each AP.

[0064] Furthermore, for example, a Sharing AP may, during the coordination negotiation phase, not send measurement information to other APs or receive measurement information from other APs, but instead determine control information to be sent and received between multiple APs performing Multi-AP coordinated communication, and then transmit or receive the determined control information during the coordinated signal transmission phase. One example of this operation is the C-SR subtypes Rough one-way coordination or Complex one-way coordination. Rough one-way coordination is a C-SR transmission control method in which a Shared AP determines the transmission power of a Shared AP so as to reduce interference to the Sharing AP's destination STA. In Rough one-way coordination, the Sharing AP determines the transmission power using the measurement information it possesses, without using the Shared AP's measurement information, and the Shared AP determines its transmission power based on the measurement information or control information notified by the Sharing AP. Note that Rough one-way coordination may also be selected as a coordinated control method between one Sharing AP and two or more Shared APs. Furthermore, Complex one-way coordination is a C-SR transmission control method in which one Sharing AP and two or more Shared APs cooperate. In Complex one-way coordination, a Shared AP determines its transmission power so as to reduce interference to the destination STA of the Sharing AP and the destination STA of other Shared APs.Furthermore, in Complex one-way coordination, the Sharing AP determines its transmit power using the measurement information it possesses, without using the measurement information of the Shared AP, and the Shared AP determines its transmit power based on the measurement information notified by the Sharing AP and the measurement information received from other Shared APs.

[0065] Figure 8 shows an example of operation for AP100 and STA200. In the example in Figure 8, as shown in Figure 1, an example of operation for BSS1, which consists of AP1 and STA1 belonging to AP1, and an example of operation for BSS2, which consists of AP2 and STA2 belonging to AP2, are shown. The details of operation for AP100 and STA200 when the Multi-AP cooperation type is C-SR will be explained below, but the frame exchange sequence shown in Figure 8 can also be applied to other Multi-AP cooperation types and subtypes.

[0066] In Figure 8, AP1 and AP2 each transmit beacon signals. At this time, STA1 and STA2 acquire (or generate) measurement information based on the respective beacon signals from AP1 and AP2. For example, STA1 generates BSS measurement information (e.g., path measurement information in Figure 1a) using the beacon signal from AP1, and generates OBSS measurement information (e.g., path measurement information in Figure 1d) using the beacon signal from AP2. Similarly, for example, STA2 generates BSS measurement information (e.g., path measurement information in Figure 1b) using the beacon signal from AP2, and generates OBSS measurement information (e.g., path measurement information in Figure 1c) using the beacon signal from AP1.

[0067] In Figure 8, AP1 sends a Measurement report poll signal to STA1, and AP2 sends a Measurement report poll signal to STA2. When STA1 receives a Measurement report poll signal from AP1, it includes measurement information (e.g., path loss values) for paths a) and d) shown in Figure 1 in the Measurement report and sends it to AP1. Similarly, when STA2 receives a Measurement report poll signal from AP2, it includes measurement information (e.g., path loss values) for paths b) and c) shown in Figure 1 in the Measurement report and sends it to AP2. As an example, each path loss value may be derived from the difference between the transmitted power value included in the beacon signal received by each STA from each AP and the received power value of the beacon signal measured by each STA. AP100 may also notify STA200 via the Measurement report poll signal that it will include the received power value of each beacon signal in the Measurement report. In this case, AP 100 may derive the path loss value from the difference between the transmitted power value of the beacon signal transmitted by AP 100 and the received power value of the beacon signal notified by STA 200. In another example, AP may transmit an NDPA (Null Data PPDU Announcement) frame and an NDP (Null Data PPDU) signal (not shown). Each path loss value may be derived from the difference between the transmitted power value contained in the NDPA or other notification signal (e.g., management frame) received by each STA from each AP and the received power value measured by each STA after receiving the NDP. For example, STA 200 may derive measurement information in the measurement information acquisition phase based on the received power value or interference power value obtained using the beacon signal. Alternatively, the processing in the measurement information acquisition phase may be performed based on information obtained using NDP or data frames instead of beacon signals. Beacons, NDPs, NDPAs, data frames, etc., may be transmitted before the measurement information acquisition phase or during the measurement information acquisition phase.

[0068] In Figure 8, for example, AP1 acts as a Sharing AP and manages Multi-AP cooperative communication. In this case, AP1, as a Sharing AP, performs scheduling and notifies AP2 of the scheduling information via a Multi-AP Trigger signal (Trigger frame). Based on the scheduling information contained in the Multi-AP Trigger signal, AP1 (as a Sharing AP) and AP2 (as a Shared AP) transmit data to their subordinate STA1 and STA2 via Multi-AP cooperative communication.

[0069] As shown in Figure 8, the Sharing AP may omit the transmission of the Multi-AP request signal and the reception of the Multi-AP response signal during the cooperative negotiation phase described above. However, the Sharing AP may still transmit the Multi-AP request signal and receive the Multi-AP response signal.

[0070] Figure 9 shows another example of operation for AP100 and STA200. In the example in Figure 9, as shown in Figure 2, examples of operation for AP1, STA1 and AP2 belonging to AP1, STA2 and AP3 belonging to AP2, and STA3 belonging to AP3 are shown. The following describes the details of operation for AP100 and STA200 when the Multi-AP coordination type is C-SR and the subtype is rough one-way coordination, but the frame exchange sequence shown in Figure 9 can also be applied to other Multi-AP coordination types and subtypes.

[0071] In Figure 9, AP1, AP2, and AP3 each transmit beacon signals. At this time, STA1, STA2, and STA3 acquire (or generate) measurement information based on the beacon signals of AP1, AP2, and AP3. For example, STA1 generates measurement information (e.g., RSSI) regarding the received signal power using the beacon signal from at least one of AP2 and AP3 (also called, for example, OBSS AP). Similarly, for example, STA2 generates measurement information regarding the received signal power using the beacon signal from at least one of AP1 and AP3. Similarly, for example, STA3 generates measurement information regarding the received signal power using the beacon signal from at least one of AP1 and AP2.

[0072] Furthermore, STA1 may extract and store beacon signal transmission power information contained in the beacon signal from at least one of AP2 and AP3, STA2 may extract and store beacon signal transmission power information contained in the beacon signal from at least one of AP1 and AP3, and STA3 may extract and store beacon signal transmission power information contained in the beacon signal from at least one of AP1 and AP2. In addition, STA1 may calculate and store the path loss between AP2 and STA1 or between AP3 and STA1 from the received signal power information and transmitted power information of at least one beacon signal from AP2 and AP3. Similarly, STA2 may calculate and store the path loss between AP1 and STA2 or between AP3 and STA2 from the received signal power information and transmitted power information of at least one beacon signal from AP1 and AP3.

[0073] In Figure 9, AP1 sends a Measurement report poll signal to STA1, AP2 sends a Measurement report poll signal to STA2, and AP3 sends a Measurement report poll signal to STA3. When STA1 receives a Measurement report poll signal from AP1, it includes the RSSI generated using the beacon signals from at least one of AP2 and AP3 in its Measurement report and sends it to AP1. Similarly, when STA2 receives a Measurement report poll signal from AP2, it includes the RSSI generated using the beacon signals from at least one of AP1 and AP3 in its Measurement report and sends it to AP2. Likewise, when STA3 receives a Measurement report poll signal from AP3, it includes the RSSI generated using the beacon signals from at least one of AP2 and AP3 in its Measurement report and sends it to AP2.

[0074] In Figure 9, for example, AP1 acts as a Sharing AP and manages Multi-AP cooperative communication. In this case, AP1, as a Sharing AP, performs scheduling and notifies AP2 and AP3 of scheduling information via a Multi-AP Trigger signal (Trigger frame). For example, if AP1 decides to perform cooperative transmission using C-SR rough one-way coordination, it may send a Multi-AP Trigger signal to AP2 and AP3, which are Shared APs, containing AP1's transmission power value, AP2's allowable transmission power value (parameters related to AP2's transmission power), and AP3's allowable transmission power value (parameters related to AP3's transmission power). Based on the scheduling information contained in the Multi-AP Trigger signal, AP1 (as a Sharing AP) and AP2 and AP3 (as Shared APs) transmit data to their subordinate STA1, STA2, and STA3 via Multi-AP cooperative communication. The allowable transmission power value (parameters related to transmission power) to be sent to AP2 and AP3 may be derived for each MCS of the signal transmitted by AP1.

[0075] In this embodiment, AP 100 determines parameters for Multi-AP cooperative communication (for example, parameters related to the transmission power of the Shared AP), sets the determined parameters in an area (field, for example, a common information section) where information common to other APs is stored, and transmits a control signal (for example, a Multi-AP Trigger signal). For example, AP 100, which is a Sharing AP, stores values ​​that are individually set for each of the multiple nodes such as AP 100 and STA 200 in the scheduling information for Multi-AP cooperative communication for multiple other APs 100, which are Shared APs, in an individual information field (also called an individual information section), and stores values ​​that are commonly set for nodes such as AP 100 and STA 200 in a common information field (also called a common information section).

[0076] The Sharing AP may, for example, use at least one of the Multi-AP request signal and the Multi-AP Trigger signal to notify the Shared AP of parameters related to the Shared AP's transmit power (e.g., the transmit power value to be allowed for the Shared AP) through Multi-AP cooperative communication scheduling information. The Shared AP's allowable transmit power value may, for example, indicate the upper limit of the Shared AP's transmit power. AP 100 may, for example, determine the allowable transmit power value of other APs performing Multi-AP cooperative communication based on a Measurement report from STA 200.

[0077] Furthermore, parameters related to the transmit power of a Shared AP may be information that is set in common for multiple Shared APs. In this case, the parameters related to the transmit power of a Shared AP may be stored in a common information field and may not be stored in an individual information field.

[0078] [Example of Frame Format] Next, we will describe an example of the format of a Multi-AP Trigger frame (also called Multi-AP Trigger or Multi-AP Trigger signal), which is one of the frames used to control Multi-AP cooperative communication, as shown in Figures 8 and 9. The format of the Multi-AP Trigger signal may be defined by extending (or reusing) the format of the Trigger frame in the IEEE 802.11 standard (for example, the 802.11be modified standard, see Non-Patent Literature 2).

[0079] Figure 10 shows an example of the format of a Multi-AP Trigger frame. As shown in Figure 10, the Multi-AP Trigger frame includes a "Common Info field," a "Special User Info field," and a "User Info List." The Common Info field contains information common to one or more APs 100 that are the destinations of the Multi-AP Trigger frame (common information). The Special User Info field also contains information common to the APs 100, similar to the Common Info field. The User Info List contains, for example, multiple individual "User Info fields" (individual information) for each of the multiple APs 100 that are the destinations of the Multi-AP Trigger frame. Note that the Special User Info field may be placed at the beginning of the User Info List field, for example. Alternatively, the Trigger frame format may not include the Special User Info field, and a separate field may be provided to store common information.

[0080] Figure 11 shows an example of the format for the Common Info field, and Figure 12 shows an example of the format for the Special User Info field.

[0081] The Common Info field shown in Figure 11 includes, for example, a "Trigger Type" subfield that indicates the type of trigger frame. For example, one of the trigger frame types may include a value indicating that it is a frame used to control multi-AP cooperative communication (e.g., a multi-AP trigger frame).

[0082] The Special User Info field shown in Figure 12 is a field in which a special AID (Association ID, e.g., AID=2007) is set in the User Info field. The Special User Info field includes a "PHY Version Identifier" subfield that indicates the version of the IEEE 802.11 standard (e.g., EHT, UHR, or other versions later than UHR).

[0083] Furthermore, the method for indicating that a frame is used to control Multi-AP cooperative communication is not limited to using the Trigger type subfield. For example, if the PHY Version Indenter indicates a UHR or a later version, AP100 (e.g., Shared AP) may be considered to be a frame used to control Multi-AP cooperative communication (e.g., a Multi-AP Trigger signal). Alternatively, a bit that is Reserved (undefined) in an existing standard (e.g., 11be), or a newly added field, may be used to indicate that a frame is used to control Multi-AP cooperative communication.

[0084] Figures 13 and 14 show examples of information for Multi-AP cooperative communication control stored in the Multi-AP Trigger signal. Figures 13(a) and 14(a) show examples of information (subfields) stored in the common information field of the Multi-AP Trigger signal, which notifies multiple STA 200s of common information. Figures 13(b) and 14(b) show examples of information (subfields) stored in the individual information field (e.g., User Info field) of the Multi-AP Trigger signal, which notifies multiple STA 200s of individual information.

[0085] Each piece of information shown in Figures 13(a) and 14(a) may be included in either the Common Info field or the Special User Info field, for example, with some information in the Common Info field and the remaining information in the Special User Info field. Furthermore, each piece of information shown in Figures 13(a) and 13(b) may be included in one frame (e.g., a Multi-AP Trigger signal) or in another frame (e.g., a frame transmitted during the coordinating negotiation phase, not shown in Figures 8 and 9). Similarly, each piece of information shown in Figures 14(a) and 14(b) may be included in one frame (e.g., a Multi-AP Trigger signal) or in another frame (e.g., a frame transmitted during the coordinating negotiation phase, not shown in Figures 8 and 9). Each piece of information shown in Figures 13(a) and 14(a) may be included in the Common Info field or the Special User Info field by using (or replacing) any of the subfields in Figures 11 and 12. For example, Trigger Type information may be included in the Common Info field using the Trigger Type subfield in Figure 11. Similarly, PPDU Length information may be included in the Common Info field using (or replacing) the UL Length subfield in Figure 11. BW information may be included in the Common Info field using (or replacing) the UL BW subfield in Figure 11 and / or the UL Bandwidth Extension subfield in Figure 12. The information shown in Figures 13(a) and 14(a) may be included in the Trigger Dependent Common Info subfield in Figure 11 and / or the Trigger Dependent User Info subfield in Figure 12.

[0086] In Figures 13 and 14, the "Trigger Type subfield" indicates the type of trigger frame (also called the trigger type, or the type of signal that AP 100 has STA 200 transmit). In Figures 13 and 14, for example, one of the trigger types specified by the Trigger Type subfield may be Multi-AP cooperative communication (e.g., Multi-AP cooperative communication method). Also, for example, the Trigger Type subfield may include a field (subfield) that specifies the Multi-AP cooperative type (e.g., Multi-AP Type) or subtype in Multi-AP cooperative communication (examples will be described later).

[0087] The "PPDU Length subfield" indicates the period during which multi-AP cooperative communication controlled by the trigger frame takes place. The value of the PPDU Length subfield may be, for example, the period until the end of the transmission opportunity (TXOP) acquired by the Sharing AP, the period during which the Sharing AP allows cooperative communication to the Shared AP, the length of the PPDU expected to communicate after the Multi-AP Trigger, or the expected time until the completion of reception of the ACK signal expected after the PPDU.

[0088] The "BW subfield" indicates the transmission bandwidth for multi-AP cooperative communication controlled by the trigger frame. For example, the value of the BW subfield may be the bandwidth allocated to the TXOP acquired by the Sharing AP, the bandwidth used by the Sharing AP during multi-AP cooperative communication, the bandwidth permitted to the Shared AP during multi-AP cooperative communication, or an even broader bandwidth that includes the bandwidth permitted to the Shared AP during multi-AP cooperative communication.

[0089] The "Shared AP ID subfield" indicates an identifier for identifying a Shared AP in multi-AP cooperative communication. The value of the Shared AP ID subfield may be an ID individually assigned to AP100, or an ID assigned to each Shared AP by the Sharing AP.

[0090] The "RU Allocation subfield" indicates the frequency resources (e.g., RU (Resource Unit)) allocated to multi-AP cooperative communication controlled by the trigger frame. For example, the value of the RU Allocation subfield may be the bandwidth permitted by the Sharing AP as usable bandwidth for the Shared AP during multi-AP cooperative communication, or it may specify some or all of the resources within the bandwidth indicated by the BW subfield. In this embodiment, as shown in Figures 13(b) and 14(b), if there are multiple Shared APs, the value of the RU Allocation subfield may be individually different in the User Info field corresponding to each of the multiple Shared APs. Alternatively, the value of the RU Allocation subfield may be a value (bandwidth) that partially overlaps for multiple Shared APs, or the same value (bandwidth) may be specified for all of the multiple Shared APs.

[0091] The "Sharing AP Tx Power subfield" indicates the transmission power value of the Sharing AP during multi-AP cooperative communication. The value of the Sharing AP Tx Power subfield may be determined by AP1. For example, it may be determined based on the path loss value between the Sharing AP (AP1 in Figure 2) and the STA200 belonging to the Sharing AP (STA1 in Figure 2). The path loss value between AP1 and STA1 may be, for example, the path loss value held by STA1 when generating measurement information. Alternatively, for example, the path loss value between AP1 and STA1 may be derived based on the received power value of the signal (e.g., Measurement report) received by AP1 from STA1 and the transmitted power value of the Measurement report included in the Measurement report.

[0092] Furthermore, for example, the transmit power value of the Sharing AP may be determined such that the SINR of STA1 satisfies a predetermined quality (desired reception quality; for example, an SINR that results in a packet error rate of 10% or less). For example, the transmit power value of AP1, which is a Sharing AP, may be derived according to equation (1). In equation (1), TxPower AP1 This indicates the transmission power value of AP1, IN STA1,max This indicates the maximum interference noise power received by STA1 from AP2 (e.g., the RSSI of AP2's beacon signal, as notified by STA1's Measurement Report), and the SINR required This indicates the SINR required for STA1 to receive a predetermined MCS, and Pathloss AP1,STA1 This indicates the path loss value between AP1 and STA1. TxPower AP1 = IN STA1,max + SINR required + Pathloss AP1,STA1 (1)

[0093] Alternatively, AP1 may receive link margin information from STA1 and determine the transmission power for cooperative transmission. For example, when AP1 transmits a signal to STA1 and AP1 receives link margin information based on the signal quality assessment when STA1 receives the signal, AP1 may use the value obtained by adding or subtracting the link margin information to / from the transmission power of the signal transmitted to STA1 as the transmission power (TxPower AP1 in cooperative communication). Note that the link margin information is the excess received power value required to satisfy a predetermined reception quality and is expressed by Equation (2). In Equation (2), the received signal detection threshold is, for example, Clear Channel Assessment-Energy Detect (CCA-ED). LinkMargin = Received signal power - Received signal detection threshold (2)

[0094] Note that the transmission power of AP1 is not limited to the control based on feedback information from STA1 such as Measurement report and link margin information, and may be determined by AP1 based on regulation values in the radio frequency, the capabilities of AP1, the control policies of AP1 (e.g., low power consumption control, communication reliability control (QoS: Quality of Service, etc.), etc.).

[0095] The "Shared AP Tx Power subfield" indicates the transmit power value of the Shared AP during multi-AP cooperative communication. The Shared AP transmit power value may be a parameter used to determine the transmit power of the Shared AP node (AP100 (Shared AP) or STA200 associated with the Shared AP). For example, it may be the expected transmit power value for the Shared AP node, the upper limit (or allowable transmit power value) of the transmit power value, the ratio of the expected transmit power value to the transmit power value used by the Shared AP during measurement, or the ratio of the upper limit to the transmit power value used by the Shared AP during measurement. Alternatively, the Shared AP transmit power value may be the value specified by the Shared AP Tx Power subfield with a margin added (e.g., added or subtracted). The margin may be, for example, a value determined according to the propagation path conditions to ensure the success rate (or reception quality) of communication, or a value estimated based on other parameters such as MCS, number of streams, transmit antenna weight, steering matrix, and precoding matrix. A configuration example for the Shared AP Tx Power subfield will be discussed later.

[0096] A Sharing AP may transmit the Shared AP Tx Power subfield in a common information field (for example, at least one of the Common Info field and the Special User Info field) (see, for example, Figure 13). This ensures that the Shared AP transmit power value specified by the Shared AP Tx Power subfield is applied commonly to multiple Shared APs controlled by the Multi-AP Trigger signal.

[0097] Alternatively, the Sharing AP may transmit the Shared AP Tx Power subfield within a separate information field (e.g., the User Info field) (see, for example, Figure 14). This ensures that the Shared AP transmit power value specified by the Shared AP Tx Power subfield is applied individually to each of the multiple Shared APs controlled by the Multi-AP Trigger signal.

[0098] For example, AP100 (e.g., Sharing AP) includes the information shown in Figure 13 in the Multi-AP Trigger frame when the Multi-AP cooperation type is of a certain type (e.g., corresponding to the first type), and includes parameters related to the transmission power of the Shared AP used for Multi-AP cooperative communication (e.g., Shared AP Tx Power subfield) in the common information field. The certain Multi-AP cooperation type may be, for example, one-way coordination of C-SR in Multi-AP cooperative communication (e.g., Rough one-way coordination).

[0099] As mentioned above, in Rough one-way coordination, compared to Optimal coordination, the Sharing AP receives less information (e.g., measurement information) from multiple Shared APs. Therefore, compared to Optimal coordination, it is more difficult to optimize individually for multiple Shared APs, and the performance improvement expected from cooperative control by Rough one-way coordination (e.g., the total communication rate during simultaneous communication) may be suppressed. However, in environments where the impact of individual optimization is small, for example, in environments where there is little interference between them and high communication rates are expected from both Sharing APs and Shared APs, the impact of Rough one-way coordination on Multi-AP cooperative communication is small, and even if common transmit power information (e.g., Shared AP Tx Power subfield) is notified to multiple Shared APs, high performance can be maintained.

[0100] Furthermore, for example, if AP100 (e.g., Sharing AP) has a Multi-AP cooperation type that is different from one of the above types (e.g., corresponding to the second type), it includes the information shown in Figure 14 in the Multi-AP Trigger frame and sets parameters related to the transmission power of the Shared AP used for Multi-AP cooperative communication (e.g., Shared AP Tx Power #1 to #N subfield) in the individual information field.

[0101] Furthermore, a certain Multi-AP coordination type is not limited to Rough one-way coordination, but may include other types as well.

[0102] [Example of Shared AP Tx Power] Next, we will describe an example of configuring the Shared AP Tx Power subfield, which is indicated by the Multi-AP Trigger signal. Below, we will describe the configuration of the wireless communication system shown in Figure 2 as an example.

[0103] AP1 (Sharing AP) may determine the allowable transmit power of the Shared APs (e.g., at least one of AP2 and AP3) (e.g., the value of the Shared AP Tx Power subfield) based on the interference power of STA1 (e.g., allowable interference power) that satisfies a predetermined quality with the transmit power of AP1 ("Sharing AP Tx Power" shown in Figure 13 or Figure 14).

[0104] In this case, when determining the allowable transmit power of multiple Shared APs, several formulas can be considered.

[0105] For example, the allowable transmit power of a Shared AP, APi (where i is a number identifying the AP as a Shared AP; for example, i=2 or 3 in Figure 2), may be derived according to equation (3). SharedAPTxPower APi = ARIL STA1 × Pathloss APi,STA1 ÷ NumberOfInterferenceAP (3)

[0106] In equation (3), SharedAPTxPower APi This indicates the allowable transmit power of the API, and ARIL STA1 This indicates the allowable interference power of STA1 belonging to Sharing AP (AP1), and Pathloss APi,STA1 `APi` indicates the path loss value between APi and STA1 (the path loss value between APi and STA1), and `NumberOfInterferenceAP` indicates the number of APs to be treated as interference. The number of APs to be treated as interference may be, for example, the number of Shared APs controlled by the Sharing AP, or it may include the number of other APs not controlled by the Sharing AP.

[0107] Note that in equation (3), the power values ​​are expressed as true values. The same applies to the formulas used in the following explanation.

[0108] For example, if the Shared AP is one station, AP2 (and does not include AP3), then NumberOfInterferenceAP=1, and the allowable transmit power of the Shared AP AP2 (i=2), derived according to equation (3), is expressed as in equation (4). SharedAPTxPower AP2 = ARIL STA1 × Pathloss AP2,STA1 (4)

[0109] Furthermore, for example, if there are two Shared APs, AP2 and AP3, then NumberOfInterferenceAP=2, and the allowable transmit power of Shared AP AP2 (i=2), derived according to equation (3), is expressed as shown in equation (5). SharedAPTxPower AP2 = ARIL STA1 × Pathloss AP2,STA1 ÷ 2 (5)

[0110] Similarly, for example, if the Shared AP is one station of AP3 (excluding AP2), then NumberOfInterferenceAP=1, and the allowable transmit power of AP3 (i=3), which is the Shared AP derived according to equation (3), is expressed as in equation (6): SharedAPTxPower AP3 = ARIL STA1 × Pathloss AP3,STA1 (6)

[0111] Furthermore, for example, if there are two Shared APs, AP2 and AP3, then NumberOfInterferenceAP=2, and the allowable transmit power of Shared AP AP3 (i=3), derived according to equation (3), is expressed as shown in equation (7). SharedAPTxPower AP3 = ARIL STA1 × Pathloss AP3,STA1 ÷ 2 (7)

[0112] Note: ARIL STA1 This can be derived, for example, according to equation (8). In equation (8), TxPower AP1This indicates the transmit power value of AP1 (Sharing AP), and SINR required This indicates the expected reception quality in STA1 (for example, reception quality for receiving a signal using a predetermined MCS; SINR (Signal to Interference and Noise Ratio)). ARIL STA1 = TxPower APi ÷ Pathloss APi,STA1 ÷ SINR required (8)

[0113] The permissible transmit power of a Shared AP derived according to equation (3) is the permissible transmit power for each Shared AP, depending on the distance (path loss value) from STA1 belonging to the Sharing AP. For example, the value for each Shared AP is stored and used in the Shared AP Tx Power subfield shown in Figure 14(b).

[0114] Furthermore, for example, the allowable transmit power of an APi that is a Shared AP may be derived according to equation (9) instead of equation (3). SharedAPTxPower APi = ARIL STA1 × Pathloss APi,STA1 ×InterferencePower APi,STA1 ÷ Total Interference Power STA1 (9)

[0115] In equation (9), InterferencePower APi,STA1 For example, in the measurement information acquisition phase, AP1 collects the power value of the received signal from the APi measured at STA1 (e.g., the interference power value from the APi to STA1). Also, TotalInterferencePower STA1 This represents the total interference power value at STA1, and can be derived according to equation (10) if, for example, the Shared APs are AP2 and AP3. TotalInterferencePower STA1 = InterferencePower AP2,STA1+InterferencePower AP3,STA1 (10)

[0116] In equation (10), InterferencePower AP2,STA1 This is the power value of the received signal from AP2 measured by STA1, which AP1 collected from STA1 during the measurement information acquisition phase, and is called InterferencePower. AP3,STA1 This is the power value of the received signal from AP3 measured by STA1, which AP1 collected from STA1 during the measurement information acquisition phase.

[0117] The allowable transmit power of APi (e.g., AP2 or AP3) may be derived, for example, as an absolute value.

[0118] Furthermore, for example, AP1 (Sharing AP) may derive the path loss value between APi and STA1 based on the transmission power information of APi included in the beacon signal received from APi and the RSSI of the beacon signal received by STA1 from APi (e.g., the received power value at STA1) included in the Measurement report received from STA1.

[0119] Alternatively, STA1 may include the transmission power information of the APi's beacon signal in the Measurement report and send it to AP1 (Sharing AP). AP1 may then derive the path loss value between APi and STA1 based on the transmission power information of the APi's beacon signal included in the Measurement report received from STA1 and the RSSI of the APi's beacon signal measured by STA1.

[0120] The method for deriving the allowable transmit power value for a Shared AP is not limited to the method described above.

[0121] For example, as an alternative derivation method, STA1 may include path loss information between the Shared AP, APi, and STA1 (path loss information between APi and STA1) in the Measurement report it sends to AP1 (Sharing AP), and AP1 may obtain a path loss value based on the path loss information included in the Measurement report received from STA1. AP1 may, for example, derive an upper limit for the APi's transmit power as the APi's allowable transmit power based on the derived path loss value between APi and STA1 and STA1's desired SINR (for example, a SINR value that results in a packet error rate of 10% or less).

[0122] Furthermore, for example, the allowable transmit power of an APi, which is a Shared AP, may be derived as a relative value. For example, AP1 (Sharing AP) may derive the change in the transmit power of APi as the allowable transmit power of APi based on the RSSI of the beacon signal received by STA1 from APi (for example, the received power value at STA1), which is included in the Measurement report received from STA1 (for example, with the RSSI as the reference). The change in the transmit power of APi may also be, for example, the relative value of the transmit power of APi's cooperative transmission in Multi-AP cooperative communication to the transmit power of APi's beacon signal.

[0123] In this case, for example, each Shared AP (including AP2 and AP3) may buffer the transmit power value of the most recently transmitted beacon signal. The Shared AP may determine its transmit power value based, for example, on the transmit power value held in the buffer and the allowable transmit power value (relative value; for example, the change in AP2's transmit power) included in the Multi-AP Trigger signal instructed by AP1.

[0124] For example, Pathloss in equation (9) APi,STA1 ×InterferencePower APi,STA1 This corresponds to the transmission power of the API's beacon signal during beacon measurement. Therefore, the change in the API's transmission power is measured using SharedAPTxPower. APi ÷(Pathloss APi,STA1×InterferencePower APi,STA1 In this case, AP1 may notify the Shared AP of a value according to equation (11) in the Multi-AP Tigger signal as the allowable transmit power value for the Shared AP. The value according to equation (11) will be the same for multiple different Shared APs. SharedAPTxPower APi ÷(Pathloss APi,STA1 ×InterferencePower APi,STA1 ) = ARIL STA1 ÷ Total Interference Power STA1 (11)

[0125] The above explains an example of configuring the Shared AP Tx Power subfield.

[0126] AP1 (Sharing AP) notifies other APs of a Multi-AP Trigger signal that includes AP1's transmit power information (e.g., the Sharing AP Tx power value) and the other APs' (Shared APs) allowable transmit power information (e.g., the Shared AP Tx power value), as shown in Figures 13 and 14, for example.

[0127] For example, if the permissible transmit power information of other APs (Shared APs) is derived according to equation (3) or equation (9), the permissible transmit power information is expected to be different for each AP. Therefore, a format may be applied to the Multi-AP Trigger signal in which the transmit power value of the Shared AP during Multi-AP cooperative communication (Shared AP Tx Power subfield) is stored in an individual information field (e.g., User Info field), as shown in Figure 14.

[0128] Furthermore, for example, if the allowable transmit power information of other APs (Shared APs) is derived according to equation (11), the allowable transmit power value will be the same for all other APs. For this reason, a format may be applied to the Multi-AP Trigger signal in which the transmit power value of the Shared AP during Multi-AP cooperative communication (Shared AP Tx Power subfield) is stored in a common information field (for example, at least one of the Common Info field and the Special User Info field), as shown in Figure 13.

[0129] In Figure 9, the Shared APs (e.g., AP2 and AP3) determine destination STAs (e.g., STA2 and STA3) that can be communicated with using a transmit power less than or equal to the Shared AP's allowable transmit power value, as indicated in the Multi-AP Trigger signal received from the Sharing AP (e.g., AP1). If the Shared APs (AP2 and AP3) are notified of an absolute allowable transmit power value in the Multi-AP Trigger signal received from AP1, for example, they may determine their transmit power value based on the absolute allowable transmit power value. Alternatively, if the Shared APs (AP2 and AP3) are notified of a relative allowable transmit power value in the Multi-AP Trigger signal received from AP1, for example, they may determine their transmit power value based on the transmit power value of the most recently transmitted beacon signal held in the buffer and the notified relative allowable transmit power value.

[0130] Alternatively, instead of determining the transmit power value of a Shared AP based on the most recently transmitted beacon signal, Shared APs (e.g., AP2 and AP3) may determine the transmit power value according to the following method.

[0131] For example, beacon signals transmitted by Shared APs (e.g., AP2 and AP3) may include a transmission parameter identifier as information to identify the transmission parameters. These transmission parameters may include, for example, the transmission power value, the number of transmitting antennas, and a weighting matrix for multi-antenna transmission (such as a steering matrix). Shared APs may include different transmission parameter identifiers for beacon signals with different transmission parameters. If a Shared AP's beacon signal includes a transmission parameter identifier, the Shared AP maintains information about the most recently transmitted beacon signal set of transmission parameter identifiers and transmission power values. AP1, a Sharing AP, transmits a Multi-AP Trigger signal to the Shared APs that includes the transmission parameter identifier of the Shared AP's beacon signal for Measurement. When determining the transmission power, the Shared APs may determine the transmission power value in coordinated transmission based on the transmission power value of the beacon signal that matches the transmission parameter identifier included in the Multi-AP Trigger signal.

[0132] Furthermore, Shared APs (e.g., AP2 and AP3) may derive the path loss value between Shard APi and STAi (the path loss value between APi and STAi) from the received power value of the signal containing the Measurement report received from the destination STA (e.g., STA2 and STA3) and the transmitted power value of the Measurement report contained in the Measurement report.

[0133] For example, APi (AP2 and AP3 in Figure 2) may determine the expected RSSI at STAi based on the APi's transmit power value and the path loss value between APi and STAi. APi may also derive the power value of the signal that STAi receives from AP1 in one-way coordination (e.g., interference signal power value) based on the RSSI of the AP1 beacon signal measured by STAi and included in the Measurement report received from STAi (e.g., the received power value at STAi) and the AP1 transmit power value included in the Multi-AP Trigger signal.

[0134] Furthermore, AP2 may estimate the interference signal power value from AP3 using, for example, the allowable transmit power value of AP3 indicated in the Multi-AP Trigger signal received from AP1. AP2 may then estimate the interference signal power value that STA2 receives during coordinated transmission from the estimated interference signal power value from AP1 and the interference signal power value from AP3. Similarly, AP3 may estimate the interference signal power value from AP2 using, for example, the allowable transmit power value of AP2 indicated in the Multi-AP Trigger signal received from AP1. AP3 may then estimate the interference signal power value that STA3 receives during coordinated transmission from the estimated interference signal power value from AP1 and the interference signal power value from AP2.

[0135] Furthermore, an APi (AP2 and AP3 in Figure 2) may derive (or estimate) the SINR of an STAi based on the expected RSSI value of the STAi belonging to the APi and the estimated interference signal power value. If the SINR of the STAi meets a predetermined quality (for example, an SINR that results in a packet error rate of 10% or less), the APi may decide to participate in one-way coordination, and if the SINR of the STAi does not meet the predetermined quality, the APi may decide not to participate in one-way coordination.

[0136] In Figure 9, after a predetermined time has elapsed since the Multi-AP Trigger signal was transmitted and received (for example, after SIFS (Short Inter Frame Space)), AP1 transmits a data signal to STA1 using AP1's transmit power value. If AP2 participates in one-way coordination, it transmits a data signal to STA2 using AP2's transmit power value; if AP2 does not participate in one-way coordination, it does not transmit a data signal to STA2. Similarly, if AP3 participates in one-way coordination, it transmits a data signal to STA3 using AP3's transmit power value; if AP3 does not participate in one-way coordination, it does not transmit a data signal to STA3.

[0137] The above describes examples of the operation of AP100 and STA200 according to this embodiment.

[0138] In this embodiment, AP 100, which is a Sharing AP, sets parameters related to Multi-AP cooperative communication (e.g., Shared AP Tx Power subfield) for multiple APs (Shared APs) that perform Multi-AP cooperative communication in a common information field in the Trigger frame, where information common to multiple APs is stored, and transmits the Trigger frame. Then, AP 100, which is a Shared AP, controls the Multi-AP cooperative communication based on the parameters (e.g., Shared AP Tx Power subfield) contained in the common information field of the received Trigger frame.

[0139] By storing the transmitted power information of the Shared AP in a common information field, the amount of information (number of bits) required to notify multiple Shared APs of the transmitted power information can be reduced, thereby improving communication efficiency.

[0140] Furthermore, in the format shown in Figure 13, for example, one parameter (Shared AP Tx Power subfield) from the parameters used for Multi-AP cooperative communication is assigned to a common information field (e.g., Control Information subfield or Special User Info field) for each user (e.g., Shared AP) included in the User Info field shown in Figure 14. This allows for an increase in the number of bits assigned to a single type of transmit power value, thereby improving the accuracy of communication control (e.g., transmit power control).

[0141] Therefore, according to this embodiment, the efficiency of transmission control in wireless communication (for example, multi-AP cooperative communication) can be improved.

[0142] (Embodiment 2) The AP and STA according to this embodiment may be the same as AP100 and STA200 according to Embodiment 1.

[0143] This embodiment describes a case where parameters related to the transmit power of a Shard AP (e.g., Shared AP Tx Power subfield) are set (and notified) for each frequency resource (bandwidth).

[0144] Below, we will describe the configuration of the wireless communication system shown in Figure 2 as an example.

[0145] For example, STA1, which belongs to AP1 (a Sharing AP), may generate (or measure) the received power value of beacon signals received from AP2 and AP3 (Shared APs) for each frequency resource (bandwidth), and send a Measurement report including the received power value to AP1. For example, the frequency resources from which the received power value is generated may be every 20 MHz, every 80 MHz, or every other frequency bandwidth. For example, the other frequency bandwidth may be a bandwidth narrower than a continuous 20 MHz, or a non-contiguous bandwidth.

[0146] AP1, which is a Sharing AP, may use the power information for each frequency resource received from AP2 and AP3, which it has received from STA1, to perform scheduling and determine the transmit power value of the Sharing AP (AP1) for each frequency resource. AP1 may also determine the power information to notify the Shared APs (the allowable transmit power of the Shared APs, or information for estimating the allowable transmit power of the Shared APs) for each frequency resource. AP1 may notify AP2 and AP3 of a Multi-AP Trigger signal that includes the transmit power value of the Sharing AP for each frequency resource and the allowable transmit power value of the Shared AP for each frequency resource.

[0147] Figure 15 shows, as an example, the scheduling result for four units of frequency resources in 20MHz increments for an 80MHz bandwidth. For example, because propagation / noise conditions may differ for each bandwidth due to frequency fading, the estimated SIR (Signal to Interference Noise) may differ for each frequency resource. Therefore, as shown in Figure 15, for example, the scheduling results according to the SIR (e.g., MCS, ARIL, etc.) will differ for each bandwidth, and the power information allowed for AP2 and AP3 may also differ.

[0148] Figure 16 shows an example format of the Shared AP transmission power value (Shared AP Tx Power subfield) during Multi-AP cooperative communication, which is stored in the Multi-AP Trigger signal as a signal for Multi-AP cooperative communication control. The Shared AP Tx Power subfield shown in Figure 16 may be stored in the common information section (e.g., Common Info field or Special User Info field) shown in Figure 13(a). As shown in Figure 16, the Shared AP transmission power value ("Shared AP Tx Power" subfield) during Multi-AP cooperative communication is stored for each of the K frequency resources (e.g., BW#1, BW#2, ..., BW#K).

[0149] For example, AP2 and AP3, which are Shared APs, use the power information for each frequency resource contained in the transmitted Multi-AP Trigger signal to determine whether communication is possible during Multi-AP coordinated transmission, and to schedule Multi-AP coordinated transmission for each frequency resource.

[0150] Figure 17 shows an example of frequency resources allocated to AP1, a Sharing AP, and to AP2 and AP3, Shared APs, when AP1, a Sharing AP, schedules for 20MHz units of frequency resources within an 80MHz bandwidth. When scheduling in 20MHz units, AP1 may arbitrarily select Shared APs to be treated as interference. For example, in the example in Figure 9, AP2 and AP3 perform Multi-AP cooperative communication with AP1's communication, so signals from AP2 and AP3 may become interference. Under these conditions, when scheduling, AP1 may schedule in four patterns (interference patterns): cases where Multi-AP cooperative communication is permitted to AP2 and AP3, resulting in interference (Cases A1, B1, C1, D1 in Figure 17); cases where AP1 communicates without permitting Multi-AP cooperative communication to AP2 and AP3 (Cases A2, B2, C2, D2 in Figure 17); cases where Multi-AP cooperative communication is not permitted to AP3, but permitted to AP2, resulting in interference (Cases A3, B3, C3, D3 in Figure 17); and cases where Multi-AP cooperative communication is not permitted to AP2, but permitted to AP3, resulting in interference (Cases A4, B4, C4, D4 in Figure 17). AP1 can specify, for example, which combination of interference patterns results (or whether Multi-AP cooperative communication is permitted or not) to notify AP2 and AP3 on a per-frequency resource basis.

[0151] For example, in the example in Figure 17, the power information to be allowed when AP2 performs Multi-AP cooperative communication on all four frequency resources (or permission for Multi-AP cooperative communication on all four frequency resources) is determined. Also in the example in Figure 17, the power information to be allowed when AP3 performs Multi-AP cooperative communication on three frequency resources (or permission for Multi-AP cooperative communication on all three frequency resources) is determined. In the example in Figure 17, Multi-AP cooperative communication on the 20MHz to 40MHz frequency resources is not permitted for AP3.

[0152] When AP1 notifies AP2 and AP3 of the scheduling results shown in Figure 17, it may use the Shared AP Tx Power subfield shown in Figure 16 (for example, K=4, BW#1, BW#2, BW#3, and BW#4) to notify power information for each frequency resource. The Shared AP Tx Power subfield shown in Figure 16 may be included in the common information section, for example, as shown in Figure 13(a), or in the individual information section, as shown in Figure 14(b).

[0153] AP2 and AP3, which are shared APs, schedule multi-AP cooperative communication on the corresponding frequency resources based on the power information for each frequency resource included in the multi-AP trigger signal from AP1.

[0154] For example, if the individual information fields for AP2 and AP3 include power information for each frequency resource permitted during Multi-AP cooperative communication, AP2 may check the power information for each frequency resource permitted for AP3. In the example in Figure 17, AP3 is not permitted to perform Multi-AP cooperative communication using the 20MHz to 40MHz frequency resource. Therefore, when scheduling during Multi-AP cooperative communication, AP2 may perform scheduling that does not consider interference from AP3 in the 20MHz to 40MHz band, and schedule that does consider interference from AP3 in other bands different from 20MHz to 40MHz.

[0155] Furthermore, for example, in the example shown in Figure 17, if the individual information fields for AP2 and AP3 include power information for each frequency resource permitted during Multi-AP cooperative communication, AP3 will schedule Multi-AP cooperative communication in a different band than 20MHz to 40MHz because Multi-AP cooperative communication is not permitted for AP3 in the 20MHz to 40MHz band.

[0156] Furthermore, for example, if the power information for each frequency resource permitted during Multi-AP cooperative communication is included as a common value in the common information field for AP2 and AP3, AP1 may notify each STA of the bandwidth information permitted during Multi-AP cooperative communication (e.g., allocation information) using individual information. AP2 and AP3 then check the bandwidth information permitted during Multi-AP cooperative communication included in the individual information field.

[0157] Figure 18 shows an example of the format of a Multi-AP Trigger signal when power information for each frequency resource during Multi-AP cooperative communication of the Shared APs (AP2 and AP3) shown in Figure 17 is stored in a common information field (Common Info field in Figure 18), and information indicating whether each frequency resource is allowed or disabled during Multi-AP cooperative communication for each Shared AP is stored in an individual information field (User Info field in Figure 18).

[0158] In Figure 18, the Common Info field may contain information other than the Shared AP Tx Power subfield, and the User Info field may contain information other than the Shared AP ID subfield and RU Allocation subfield. Furthermore, the Multi-AP Trigger signal may contain other fields different from those shown in Figure 18. Also, the format shown in Figure 18 is just an example; for example, the Shared AP Tx Power subfield may be stored in the Special User Info field instead of the Common Info field.

[0159] As shown in Figure 18, AP2 determines the bandwidth available for multi-AP cooperative communication (e.g., BW#1 to BW#4) based on the power information (Shared AP Tx Power subfield) contained in the common information field of the Multi-AP Trigger signal and the bandwidth information (RU Allocation subfield) contained in the individual information field for AP2 (e.g., Shared AP ID#1). AP2 may also determine whether or not to schedule including interference from AP3 based on the bandwidth information contained in the individual information field for AP3 (e.g., Shared AP ID#2).

[0160] Similarly, as shown in Figure 18, AP3 determines the bandwidth available for multi-AP cooperative communication (e.g., BW#1, BW#3, and BW#4) based on the power information (Shared AP Tx Power subfield) contained in the common information field of the Multi-AP Trigger signal and the bandwidth information (RU Allocation subfield) contained in the individual information field for AP3 (e.g., Shared AP ID#2).

[0161] The value of the RU Allocation subfield may be, for example, a value specified by a bandwidth specification method defined in an existing standard, or a value indicating permission / denial for each bandwidth specified in a common information field (e.g., Control Information subfield or Special User Info field) for common transmit power information of multiple Shared APs (or a specific Multi-AP cooperation type such as C-SR) (see, for example, Figure 18), or any other value that can identify the bandwidth used by the Shared AP node may be specified.

[0162] In this embodiment, the transmitted power information of the Shared AP is notified for each of the multiple frequency resources (bandwidths). This makes it possible to allocate a suitable bandwidth to each node in Multi-AP cooperative communication control for multiple nodes, even in environments where propagation conditions / noise conditions may differ for each band due to frequency fading, etc., and also makes it possible to set the transmitted power for each band, thereby improving the communication quality in Multi-AP cooperative communication.

[0163] In this embodiment, for example, as shown in Figure 17, we have described a case where AP1 (Sharing AP) is included in all combinations (cases) of APs referenced during scheduling, but this is not limited to this. In actual operation, only combinations that include Sharing AP may be set, or combinations that do not include Sharing AP may be set.

[0164] Furthermore, in this embodiment, although the sequence shown in Figure 9 was used as an example to describe the case where the number of Shared APs is two (AP2 and AP3), the embodiment is not limited to this. In this embodiment, the number of Shared APs may be one, three or more, or any other.

[0165] Furthermore, in this embodiment, the unit of frequency resources that notifies the transmitted power information of the Shared AP is not limited to 20 MHz, but may be other bandwidths. For example, other bandwidths may include a continuous bandwidth of frequency resources narrower than 20 MHz, or a non-contiguous bandwidth of frequency resources narrower than 20 MHz. An example of a non-contiguous bandwidth of frequency resources narrower than 20 MHz is a "Distributed-tone RU (DRU)," which is a RU composed of Tones that are discretely (or distributed, spread) spread across a specific bandwidth. An example of a continuous bandwidth of frequency resources narrower than 20 MHz is a "Regular RU (RRU)," which is a RU composed of multiple consecutive Tones.

[0166] For example, information indicating the unit of bandwidth (bandwidth type) to which the Shared AP's transmit power information is notified may be notified to the Shared AP. Figure 19(a) shows an example format in which the Shared AP's transmit power information (Shared AP Tx Power subfield) includes information indicating the unit of bandwidth (bandwidth type) to which the Shared AP's transmit power information is notified (e.g., "BW Type" subfield). Figure 19(b) shows an example of the association between the value of the BW Type subfield and the corresponding bandwidth type (bandwidth unit). In Figure 19, the Shared AP may, for example, identify the type of each bandwidth (BW#1 to BW#K) in the Shared AP Tx Power subfield based on the value of the BW Type subfield.

[0167] This allows the Sharing AP to notify multiple Shared APs of their transmission power information for each of several different bandwidth types, using common information.

[0168] Furthermore, in this embodiment, the number of bandwidths (frequency resources) K to which the transmitted power value of the Shared AP ("Shared AP Tx Power" subfield) is notified during Multi-AP cooperative communication is not limited to four, as shown in Figure 15 or Figure 17, but may be any other number (for example, one or two or more). For example, the value of the number of bandwidths K may be set to be variable depending on the type of communication (for example, the Multi-AP cooperative type or subtype, or communication other than Multi-AP cooperative (UL / DL or number of Multi-Users)).

[0169] Furthermore, in this embodiment, information regarding the number of bandwidths that notify the transmitted power information of the Shared AP, and information regarding the allocation of each bandwidth to the Shared AP, may be included in the Shared AP Tx Power subfield. For example, a specific value may be defined that disallows the use of the bandwidth allocated to that Shared AP Tx Power subfield. Alternatively, a specific value may be defined that indicates that the bandwidth allocated to that Shared AP Tx Power subfield should be used for different Multi-AP cooperative control.

[0170] Furthermore, in this embodiment, information notifying the bandwidth related to the Shared AP Tx Power subfield (for example, the BW Type subfield described above) and information notifying whether cooperative communication to each AP is permitted or not (for example, a subfield) may be included in the control signal (for example, the Multi-AP Trigger signal).

[0171] (Embodiment 3) The AP and STA according to this embodiment may be the same as AP100 and STA200 according to Embodiment 1.

[0172] Below, we will describe the configuration of the wireless communication system shown in Figure 2 as an example.

[0173] Embodiments 1 and 2 describe a case where the parameter stored in the common information field (e.g., Common Info field or Special User Info field) as information common to multiple Shared APs is the transmit power information of the Shared AP, but are not limited to this. The parameter stored in the common information field as information common to multiple Shared APs may be other parameters.

[0174] In this embodiment, we will describe a case in which information regarding the bandwidth available to the Shared AP during multi-AP cooperative communication (e.g., RU Allocation), which is permitted by the Sharing AP, is set as one of the parameters stored in the common information field as information common to multiple Shared APs.

[0175] For example, C-SR in Multi-AP cooperative communication is a control that enables simultaneous communication using the same bandwidth by adjusting the power across multiple nodes. Therefore, for example, when the Multi-AP cooperative type is C-SR, a common value (e.g., the same bandwidth) can be set as RU Allocation for multiple Shared APs. Note that this embodiment is not limited to application to C-SR, but may also be applied to other Multi-AP cooperative types.

[0176] Figure 20 shows an example of the format of a Multi-AP Trigger signal when information about the bandwidth available during Multi-AP cooperative communication permitted by the Sharing AP (for example, called the "Shared RU Allocation" subfield) is stored in the common information field. Figure 20(a) shows an example of information (subfield) stored in the common information field (for example, at least one of the Common Info field and the Special User Info field) of the Multi-AP Trigger signal, which notifies multiple STA 200s of common information. Figure 20(b) shows an example of information (subfield) stored in the individual information field (for example, the User Info field) of the Multi-AP Trigger signal, which notifies multiple STA 200s of individual information.

[0177] In Figure 20, the "Shared RU Allocation subfield" indicates the bandwidth available for multi-AP cooperative communication, specified for multiple Shared APs (e.g., AP2 and AP3 in Figure 2). The Shared RU Allocation subfield contains a value common to multiple Shared APs. The bandwidth available for a Shared AP during multi-AP cooperative communication may be, for example, part or all of the bandwidth indicated by the BW subfield.

[0178] Furthermore, the bandwidth available for Multi-AP cooperative communication specified for multiple Shared APs is not limited to the common information field; different bandwidths may be specified individually for each Shared AP in the individual information field (User Info field), overlapping bandwidths may be specified among multiple Shared APs, or the same bandwidth may be specified for all of them.

[0179] Furthermore, while Figure 20 illustrates the case where the Shared AP's transmit power information (Shared AP Tx Power subfield) and the Shared AP's available bandwidth information (RU Allocation subfield) are included in a common information field (e.g., Common Info field or Special User Info field), it is not limited to this. For example, the Shared AP's available bandwidth information (RU Allocation subfield) may be included in a common information field, and the Shared AP's transmit power information (Shared AP Tx Power subfield) may be included in an individual information field.

[0180] Furthermore, for example, the information (subfield) shown in Figure 20(a) may be included in at least one of the Common Info field and the Special User Info field. For example, the information shown in Figure 20(a) may be included in either the Common Info field or the Special User Info field. Alternatively, for example, a portion of the information shown in Figure 20(a) may be included in the Common Info field, and the remaining information may be included in the Special User Info field. For example, Figure 21 shows an example format of a Multi-AP Trigger signal in which the Special User Info field includes a transmit power value common to multiple Shared APs (Shared AP Tx Power subfield) and bandwidth information common to multiple Shared APs (Shared RU Allocation subfield).

[0181] (Variations) In the example of the frame format described above, a format based on a Trigger frame, which is one of the Control frames corresponding to 11be, was explained. However, the frame according to one embodiment of this disclosure is not limited to a Control frame such as a Trigger frame. For example, as common information containing parameters common to multiple Shared APs, it is not limited to the Common Info subfield (or Special User Info field) of the existing frame format, but a common information format for multi-AP cooperative communication may be used.

[0182] Figure 22 shows an example of a frame (e.g., a common information frame) that includes a "Shared AP Tx power" subfield that stores parameters related to the Shared AP's transmission power (e.g., the power that the Shared AP is allowed to use in multi-AP cooperative communication) and does not contain any other information. Note that the multi-AP cooperative type to which the value of the Shared AP Tx Power subfield applies may be notified in another frame (e.g., a Frame Control field) different from the frame shown in Figure 22 (for example, the Common Info field), or in a frame notified at a different timing than the frame shown in Figure 22.

[0183] Figure 23 also shows an example of a Multi-AP Trigger signal format that includes a "Multi-AP Type" subfield indicating the Multi-AP cooperation type and a "Multi-AP subtype" subfield indicating the subtype of the Multi-AP cooperation type. For example, the format of the common information field (e.g., the presence or absence of parameters common to multiple Shared APs (e.g., Shared AP Tx Power subfield)) may be switchable depending on at least one of the Multi-AP cooperation type and the subtype of the Multi-AP cooperation type.

[0184] Furthermore, the information for Multi-AP cooperative communication stored in a common information field for Multi-AP cooperative control (e.g., Common Info field or Special User Info field) may include a Shared AP Tx power subfield that stores parameters related to the power allowed for Multi-AP cooperative communication by multiple Shared APs, and may not include other information, or it may include other information used by Shared APs in Multi-AP cooperative communication in addition to the Shared AP Tx Power subfield. Figure 24 shows an example in which a shared information field for Multi-AP cooperative control (e.g., Common Info field) includes a Shared AP Tx power subfield that stores parameters related to the power allowed for Multi-AP cooperative communication by Shared APs, and a RU Allocation subfield that stores bandwidth information that Shared APs are allowed to use in Multi-AP cooperative communication.

[0185] Furthermore, the shared information field for multi-AP cooperative control stores bandwidth information (RU Allocation subfield) that Shared APs are permitted to use for multi-AP cooperative communication, and does not need to store any other information.

[0186] Furthermore, the information for Multi-AP cooperative communication stored in the common information field is not limited to the two types of information, transmission power and bandwidth, but may include other types of information as well.

[0187] Furthermore, in the above embodiment, as shown in Figure 8 or Figure 9, the description was based on the premise that the AP of the BSS controlled by the Sharing AP is a Shared AP, and the node on the Shared AP side is an AP (for example, downlink communication), but the invention is not limited to this. For example, one embodiment of the present disclosure may be applied to control targeting uplink communication, or to control targeting an environment in which downlink and uplink communication coexist.

[0188] Furthermore, while the above embodiment describes a case where common parameters (e.g., transmit power information or bandwidth information) are set for all of the multiple Shared APs, it is not limited to this. In some cases, common parameters may be set for some of the multiple Shared APs, and individual parameters may be set for the remaining Shared APs.

[0189] Furthermore, in the above embodiment, the field to which common information is notified to multiple STA200s is not limited to the Common Info field and the Special User Info field, but may also be a field for notifying common information that will be newly added in future versions of the IEEE802.11 standard (see, for example, Non-Patent Document 3).

[0190] One embodiment of the present disclosure has been described above.

[0191] While embodiments have been described above with reference to the drawings, this disclosure is not limited to such examples. It will be apparent to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims. Such modifications or alterations are also understood to fall within the technical scope of this disclosure. Furthermore, the components in the embodiments may be combined in any way without departing from the spirit of this disclosure.

[0192] In the embodiments described above, the notation "...part" used for each component may be replaced with other notations such as "...circuitry," "...assembly," "...device," "...unit," or "...module."

[0193] The interface name (frame name), field name, or subfield name described in each of the embodiments described above may be any other name.

[0194] Furthermore, in each of the embodiments described above, the field (or subfield) used for notifying control information is merely an example, and other fields or subfields may be used. Also, the number of bits used for notifying control information in each field or subfield is merely an example, and other numbers of bits may be used.

[0195] Furthermore, the signal formats described in each of the embodiments described above are merely examples, and other configurations may be used in which at least one of the following is performed: the addition of other fields or the deletion of some fields. In addition, in each of the fields described above, at least one of the following is performed: the addition of other subfields or the deletion of some subfields.

[0196] Furthermore, although the above embodiment describes application to a specific version of the IEEE 802.11 standard (e.g., 11bn), the above embodiment is not limited to application to a specific version of the IEEE 802.11 standard, but can be applied to various versions of the IEEE 802.11 standard. In addition, the above embodiment is not limited to application to the IEEE 802.11 standard, but may be applied to other communication standards or other communication technologies.

[0197] Furthermore, while the above embodiment describes, as an example, a case based on the format specified in IEEE 802.11, the format to which one embodiment of this disclosure is applied is not limited to the IEEE 802.11 format.

[0198] This disclosure can be implemented in software, hardware, or software in conjunction with hardware. Each functional block used in the description of the above embodiments may be implemented in part or in whole as an integrated circuit (LSI), and each process described in the above embodiments may be controlled in part or in whole by a single LSI or a combination of LSIs. An LSI may consist of individual chips, or it may consist of a single chip that includes some or all of the functional blocks. An LSI may have data inputs and outputs. Depending on the degree of integration, LSIs may be referred to as ICs, system LSIs, super LSIs, or ultra LSIs.

[0199] The integrated circuit implementation method is not limited to LSIs; it may also be implemented using dedicated circuits, general-purpose processors, or dedicated processors. Furthermore, a Field Programmable Gate Array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that allows for the reconfiguration of the connections and settings of circuit cells within the LSI, may also be used. This disclosure may be implemented as digital or analog processing.

[0200] Furthermore, if advancements in semiconductor technology or related technologies lead to the emergence of integrated circuit technologies that can replace LSIs, then naturally, these technologies can be used to integrate functional blocks. The application of biotechnology, for example, is a possibility.

[0201] This disclosure is applicable to all types of devices, systems, and equipment having communication capabilities (collectively referred to as communication equipment). Communication equipment may include a radio transceiver and a processing / control circuit. The radio transceiver may include a receiver and a transmitter, or both as functions. The radio transceiver (transmitter, receiver) may include an RF (Radio Frequency) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or similar. Non-exclusive examples of communication devices include telephones (mobile phones, smartphones, etc.), tablets, personal computers (PCs) (laptops, desktops, notebooks, etc.), cameras (digital still / video cameras, etc.), digital players (digital audio / video players, etc.), wearable devices (wearable cameras, smartwatches, tracking devices, etc.), game consoles, digital book readers, telehealth / telemedicine devices, vehicles or mobile transport with communication capabilities (cars, airplanes, ships, etc.), and combinations of the above-mentioned devices.

[0202] Communication devices are not limited to portable or movable devices, but also include all kinds of non-portable or fixed devices, devices, and systems, such as smart home devices (appliances, lighting fixtures, smart meters or measuring instruments, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0203] Communication includes data communication via cellular systems, wireless LAN systems, and communication satellite systems, as well as data communication using combinations of these.

[0204] Furthermore, the communication device also includes devices such as controllers and sensors that are connected to or linked to a communication device that performs the communication functions described in this disclosure. For example, this includes controllers and sensors that generate control signals and data signals used by the communication device that performs the communication functions of the communication device.

[0205] Furthermore, communication equipment includes infrastructure facilities such as base stations, access points, and any other devices, devices, and systems that communicate with or control the aforementioned non-limited types of equipment.

[0206] One embodiment of the present disclosure includes, when the type of cooperative communication is a first type, a control circuit that sets parameters relating to the cooperative communication for a plurality of access points performing the cooperative communication in a field of the control signal in which information common to the plurality of access points is stored, and a transmission circuit that transmits the control signal.

[0207] In one embodiment of the present disclosure, the control circuit sets the parameter in a field of the control signal where individual information for the plurality of access points is stored, when the type of cooperative communication is a second type different from the first type.

[0208] In one embodiment of the present disclosure, the parameter is a parameter relating to the transmit power of the access point whose coordinated communication is controlled.

[0209] In one embodiment of the present disclosure, the control circuit sets the parameters for each of the multiple bandwidths.

[0210] In one embodiment of the present disclosure, the control circuit sets information indicating whether the cooperative communication in each of the plurality of bandwidths is permitted or not in a field where individual information is stored for each of the plurality of access points.

[0211] In one embodiment of the present disclosure, the parameter is a parameter relating to the bandwidth used by the access point whose coordinated communication is controlled.

[0212] In one embodiment of the present disclosure, the first type is a rough one-way coordination of C-SR (Coordinated Spatial Reuse).

[0213] In one embodiment of the present disclosure, the control signal is a trigger frame, and the field is at least one of the Common Info field and the Special User Info field.

[0214] An access point according to one embodiment of the present disclosure comprises, when the type of cooperative communication is a first type, a receiving circuit that receives a control signal set in a field where common information is stored for a plurality of access points performing the cooperative communication, and a control circuit that controls the cooperative communication based on the parameters.

[0215] In a communication method according to one embodiment of the present disclosure, when the type of cooperative communication is the first type, the access point sets the parameters relating to the cooperative communication for the plurality of access points performing the cooperative communication in a field of the control signal in which information common to the plurality of access points is stored, and transmits the control signal.

[0216] In a communication method according to one embodiment of the present disclosure, when the type of cooperative communication is of type 1, the access point receives a control signal for a plurality of access points performing the cooperative communication, in which parameters relating to the cooperative communication are set in a field in which information common to the plurality of access points is stored, and controls the cooperative communication based on the parameters.

[0217] All disclosures in the specification, drawings, and abstract contained in the Japanese application 2025-004116, filed on January 10, 2025, are incorporated herein by reference.

[0218] One embodiment of this disclosure is useful for wireless communication systems.

[0219] 100 AP 101, 201 Wireless Receiver 102, 202 Preamble Demodulation Unit 103, 203 Data Demodulation Unit 104, 204 Data Decoding Unit 105 Measurement Information Storage Unit 106 Buffer Status Information Storage Unit 107 Capability Information Storage Unit 108 Scheduling Unit 109 Data Generation Unit 110 Data Encoding Unit 111 Data Modulation Unit 112 Preamble Generation Unit 113, 208 Wireless Transmitter 200 STA 205 Measurement Control Unit 206 Buffer Status Control Unit 207 Transmit Signal Generation Unit

Claims

1. An access point comprising: a control circuit that, when the type of cooperative communication is type 1, sets parameters relating to the cooperative communication for a plurality of access points performing the cooperative communication in a field of the control signal in which information common to the plurality of access points is stored; and a transmission circuit that transmits the control signal.

2. The access point according to claim 1, wherein the control circuit sets the parameter in a field of the control signal where individual information for the plurality of access points is stored, when the type of cooperative communication is a second type different from the first type.

3. The access point according to claim 1, wherein the parameter is a parameter relating to the transmission power of the access point whose coordinated communication is controlled.

4. The access point according to claim 3, wherein the control circuit sets the parameters for each of the multiple bandwidths.

5. The access point according to claim 4, wherein the control circuit sets information indicating whether the cooperative communication in each of the plurality of bandwidths is permitted or not in a field in which individual information is stored for each of the plurality of access points.

6. The access point according to claim 1, wherein the parameter is a parameter relating to the bandwidth used by the access point whose coordinated communication is controlled.

7. The access point according to claim 1, wherein the first type is a rough one-way coordination of C-SR (Coordinated Spatial Reuse).

8. The access point according to claim 1, wherein the control signal is a trigger frame, and the field is at least one of the Common Info field and the Special User Info field.

9. An access point comprising: a receiving circuit that receives a control signal set in a field where common information is stored for a plurality of access points performing cooperative communication, when the type of cooperative communication is of type 1; and a control circuit that controls the cooperative communication based on the parameters.

10. A communication method in which, when the type of cooperative communication is type 1, an access point sets parameters related to the cooperative communication for a plurality of access points performing the cooperative communication in a field of the control signal where information common to the plurality of access points is stored, and transmits the control signal.

11. A communication method in which, when the type of cooperative communication is type 1, an access point receives a control signal in which parameters relating to the cooperative communication for a plurality of access points performing the cooperative communication are set in a field in which information common to the plurality of access points is stored, and controls the cooperative communication based on the parameters.

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