Communication device and communication method

Abstract

A communication device comprising a control unit that generates low latency traffic information relating to multi-AP coordinated transmission and a wireless transmission unit that transmits the generated low latency traffic information.

Description

Communication device and communication method

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

[0002] A task group (TG) is currently developing technical specifications for 802.11be (hereinafter referred to as "11be") as a successor standard to 802.11ax (hereinafter referred to as "11ax"), a standard of the Institute of Electrical and Electronics Engineers (IEEE) 802.11 (see, for example, Non-Patent Document 1).

[0003] International Publication No. 2008 / 012114

[0004] IEEE P802.11beTM / D2.0, May 2022IEEE 802.11 / 617r3, Multi-AP Operation - Basic DefinitionIEEE 802.11-20 / 1046r14, Protected TWT Enhancement for Latency Sensitive TrafficIEEE 802.11-21 / 1046r3, Multi-AP: TWT Information SharingIEEE 802.11-21 / 1028r0, CR BSR for RTA

[0005] However, the control method for low latency traffic signals in multi-access point (AP) cooperative transmission has not been determined.

[0006] Non-limiting examples of the present disclosure contribute to providing a communication device and a communication method that improve communication efficiency of cooperative communication in wireless communication.

[0007] A communication device according to an embodiment of the present disclosure includes a control unit that generates low-latency traffic information related to Multi-AP (MAP) coordinated transmission, and a wireless transmission unit that transmits the generated low-latency traffic information.

[0008] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0009] According to an embodiment of the present disclosure, it is possible to improve communication efficiency of cooperative communication in wireless communication.

[0010] Further advantages and benefits of one embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features.

[0011] 1 is a diagram showing an example of communication in R-TWT; 2 is a diagram showing the format of a TWT element; 3 is a sequence diagram for controlling coordinated transmission during the R-TWT period among multiple APs; 4 is a block diagram showing the configuration of a downlink radio transmitting device according to embodiment 1; 5 is a block diagram showing the configuration of a downlink radio receiving device according to embodiment 1; 6 is a diagram showing control information related to R-TWT including low-latency traffic information related to MAP coordinated transmission; 7 is a diagram showing an example of operation of R-TWT coordinated transmission when a different R-TWT SP is set for each BSS; 8 is a diagram showing an example of operation of R-TWT coordinated transmission when a common R-TWT SP is set for BSSs; 9 is a sequence diagram for controlling coordinated transmission during the R-TWT period among multiple APs according to embodiment 2; 10 is a block diagram showing the configuration of a downlink radio transmitting device according to embodiment 2; Figure showing a signaling example for notifying low-latency traffic information related to MAP cooperative transmission using a negotiation signal for MAP cooperative transmission Figure showing an example of signaling for notifying low-latency traffic information related to MAP cooperative transmission using a transmission start notification signal for MAP cooperative transmission Sequence diagram for three APs using management signals to determine the TID to be used in MAP cooperative transmission Figure showing BSR format Sequence diagram for notifying low-latency traffic information related to MAP cooperative transmission using buffer information Figure showing a signaling example for notifying low-latency traffic information related to MAP cooperative transmission by combining TID bitmap and BSR Figure showing QoS Characteristics element Figure showing TCPEC element Figure showing TCLAS element Figure showing Intra-Access Category element Sequence diagram for notifying low-latency traffic information related to MAP cooperative transmission using a TSPEC element Sequence diagram for notifying low-latency traffic information related to MAP cooperative transmission using SCS control information Figure showing SCS Request Figure showing BSS BSR Sequence diagram of solution 1 of embodiment 2 Sharing depending on the presence or absence of low-latency traffic informationSequence diagram for changing APsSequence diagram for determining APs participating in Multi-AP cooperative transmission based on the presence or absence of low-latency traffic informationSchematic diagram of C-SR when each AP performs power controlSequence diagram of C-SR when each AP performs power controlDiagram showing C-SR Info RequestSchematic diagram of C-SR when only one AP performs transmit power controlSequence diagram of C-SR when only one AP performs transmit power controlSequence diagram for notifying C-SR transmission timing using a time offsetDiagram showing MAP Trigger frame for notifying time offsetSequence diagram for notifying C-SR transmission timing using the number of data unitsDiagram showing MAP Trigger frame for notifying the number of data unitsSchematic diagram of PSR-based SRSchematic diagram of DL C-SRDiagram showing MAP Trigger frame for notifying DL C-SR transmissionDiagram showing signaling for notifying TID bitmap for each linkDiagram showing signaling for notifying link bitmap for each TIDDiagram showing signaling for notifying presence or absence of TID bitmap for each link for each TID in control information

[0012] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings.

[0013] [About Multi-AP coordination] In 11be, Multi-AP (MAP) coordination (also called "cooperative communication") is being considered, in which multiple access points (also called "base stations", hereinafter referred to as "APs") cooperate with each other to transmit and receive data (see, for example, non-patent document 2).

[0014] In MAP cooperative communication, for example, an AP that has acquired a channel usage period (TXOP: Transmission Opportunity) is called a "Sharing AP." An AP may acquire a TXOP, for example, by Carrier Sense Multiple Access / Collision Avoidance (CSMA / CA). Also, in MAP cooperative communication, an AP that is cooperatively controlled by a Sharing AP is called a Shared AP. Also, in MAP cooperative communication, for example, a terminal (also called a station (STA) or non-AP STA) that belongs to (e.g., belongs to or associates with) a Sharing AP may be called a "Sharing STA," and a STA that belongs to a Shared AP may be called a "Shared STA."

[0015] MAP cooperative communication includes, for example, Joint Transmission (JT), Corrdinated Beamforming (C-BF), Coordinated Spatial Reuse (C-SR), Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA), or Coordinated Time Division Multiple Access (C-TDMA). MAP cooperative communication may be Downlink (DL) cooperative transmission or Uplink (UL) cooperative transmission.

[0016] [Regarding transmission of low latency traffic signals] 11be discusses Restricted-Target Wake Time (R-TWT), which sets a period during which low latency traffic (also called latency sensitive traffic) signals are transmitted with priority (e.g., Non-Patent Document 3).

[0017] In the present disclosure, an AP notifies other APs of control information (e.g., low-latency traffic information) of low-latency traffic signals. For example, the low-latency traffic signals include at least one of a traffic signal with priority (e.g., transmission availability information, user priority), a traffic signal with a large buffer queue size, a traffic signal with a small tolerable delay (e.g., delay bound), and a traffic signal with high required quality (e.g., media access control (MAC) service data unit (MSDU) delivery ratio). The low-latency traffic information includes at least one of a TID bitmap that determines whether transmission is available, buffer information (e.g., buffer status report (BSR)), and quality of service (QoS) information.

[0018] FIG. 1 is a diagram illustrating an example of communication in an R-TWT.

[0019] The AP notifies the STA of the R-TWT period information and transmittable low-latency traffic information in the Broadcast TWT information element (IE) included in the beacon signal (S101). The R-TWT period information includes the R-TWT Service Period (SP), which is the transmission period of the low-latency traffic signal, and the R-TWT Interval, which is the repetition period of the R-TWT.

[0020] A STA that receives a beacon signal including an R-TWT element from the AP operates in an awake state during the R-TWT SP, and during the R-TWT SP, the AP transmits a Basic Trigger frame (TF) to the STA to request transmission of UL low latency traffic (S102), the STA transmits a UL low latency traffic signal (S103), and the AP transmits a Block Acknowledgement (BA) (S104). During periods not included in the R-TWT SP, the STA operates in a power-saving mode in a doze state, and does not transmit or receive signals.

[0021] 2 is a diagram showing the format of a TWT element. Low-latency traffic information that can be transmitted during an R-TWT SP period is notified in the Restricted TWT DL Triffic Identifier (TID) Bitmap subfield and the Restricted TWT UL TID Bitmap subfield included in the TWT element shown in FIG. 2.

[0022] Each bit in the Restricted TWT DL TID Bitmap subfield and / or the Restricted TWT UL TID Bitmap subfield (hereinafter referred to as Restricted TWT DL / UL TID Bitmap) corresponds to a TID, which is used to identify the user priority of a Quality of Service (QoS) data frame and the Access Category (AC) of traffic, for example, as shown in Table 1. The user priority of a QoS data frame and the Access Category (AC) of traffic may be identified by methods other than those shown in Table 1.

[0023]

[0024] If each bit in the Restricted TWT DL / UL TID Bitmap is 1, it indicates that the corresponding TID can transmit during the R-TWT SP period. On the other hand, if each bit in the Restricted TWT DL / UL TID Bitmap is 0, it indicates that the corresponding TID cannot transmit during the R-TWT SP period.

[0025] DL / UL TID Bitmap Valid indicates whether the Restricted TWT DL / UL TID Bitmap contains valid information. For example, DL / UL TID Bitmap Valid = 1 indicates that any bit in the Restricted TWT DL / UL TID Bitmap is non-zero. DL / UL TID Bitmap Valid = 0 indicates that all TIDs are allowed to be transmitted during the R-TWT SP period.

[0026] 1 shows an example in which, during an R-TWT SP period, the AP transmits a Basic TF to the STA to request transmission of UL low latency traffic (S102), the STA transmits a UL low latency traffic signal (S103), and the AP transmits a BA (S104). However, UL transmission during an R-TWT SP period is not limited to UL transmission based on a Trigger frame. For example, during an R-TWT SP period, the STA may obtain channel access using CSMA / CA and transmit a UL low latency traffic signal to the AP.

[0027] However, the control method of low latency traffic signals in MAP cooperative transmission has not been fully investigated.

[0028] A terminal according to one embodiment of the present disclosure includes a control circuit that determines control related to low-latency traffic signals, a control circuit that determines control related to MAP cooperative transmission, and a control circuit that performs scheduling based on low-latency traffic information and control information related to MAP cooperative transmission.

[0029] A wireless communication system according to an embodiment of the present disclosure includes at least two APs (e.g., also referred to as downlink wireless transmitters in DL communication) and one STA (e.g., also referred to as downlink wireless receiver in DL communication). For example, the AP transmits a DL signal to other APs and STAs. Furthermore, the STA transmits a UL signal to the AP based on the DL signal received from the AP.

[0030] [First Embodiment] In the first embodiment, multiple APs and multiple STAs cooperate to transmit signals including low-latency traffic signals to an R-TWT SP. As an example, a method will be described below in which two APs (e.g., AP1 and AP2) transmit and receive control information (e.g., low-latency traffic information) related to low-latency traffic signals between the APs, the STAs transmit signals including UL low-latency traffic signals to the R-TWT SP, and the APs receive the signals including UL low-latency traffic signals.

[0031] The AP may transmit a signal including a DL low-latency traffic signal, and the STA may receive the signal including the DL low-latency traffic signal.

[0032] An example of the operation of the AP and STAs according to the first embodiment will now be described. Fig. 3 is a sequence diagram for controlling coordinated MAP transmission of R-TWT SPs among multiple APs as an example of the first embodiment. In this case, it is assumed that Basic Service Set (BSS) 1 includes AP 1 and STA 1, and BSS 2 includes AP 2 and STA 2.

[0033] STA1 and STA2 transmit beacon signals including capability information related to MAP cooperative transmission and capability information related to R-TWT to their respective APs (S301, S302). The signals including this capability information are not limited to beacon signals. For example, the capability information related to MAP cooperative transmission and capability information related to R-TWT may be included in an association signal transmitted from the STA to the AP.

[0034] Each AP performs a receiving process for the beacon signal transmitted from the STA, and stores the capability information regarding MAP cooperative transmission and the capability information regarding R-TWT in a buffer (S303, S304).

[0035] Each AP transmits a beacon signal including capability information regarding MAP cooperative transmission and capability information regarding R-TWT to the other APs (S305, S307). The other APs may be APs related to the Multi-AP system.

[0036] Each AP performs a receiving process for the beacon signals transmitted from the other APs, and stores the capability information regarding MAP cooperative transmission and the capability information regarding R-TWT in a buffer (S306, S308).

[0037] AP1 acquires the TXOP and operates as a Sharing AP that takes the lead in the MAP cooperative transmission. AP1 transmits a MAP cooperative transmission participation request signal to AP2 (S309).

[0038] AP2 receives the MAP cooperative transmission participation request signal (S310), determines whether to participate in the MAP cooperative transmission based on the capability information related to the MAP cooperative transmission, and transmits a MAP cooperative transmission participation response signal to AP1 (S311). At this time, AP1 may include request information related to R-TWT cooperation in the MAP cooperative transmission participation request signal. AP2 may also include response information related to R-TWT cooperation in the MAP cooperative transmission participation response signal.

[0039] AP1 receives the MAP cooperative transmission participation response signal (S312) and transmits a beacon signal including R-TWT cooperative control information (e.g., TWT element) to APs (e.g., AP2) that can participate in the MAP cooperative transmission and R-TWT cooperative transmission (S313). The R-TWT cooperative control information includes information about the duration of the R-TWT SP for each BSS and information about the type of low-latency traffic signal that can be transmitted to the R-TWT SP.

[0040] The AP2 performs a receiving process for the beacon signal including the R-TWT cooperative control information (S314).

[0041] Each AP (e.g., AP1 and AP2) includes the R-TWT control information created based on the R-TWT cooperative control information in a beacon signal and transmits it to its subordinate STAs (e.g., STA1 and STA2) (S315, S316).

[0042] Each STA (for example, STA1 and STA2) performs a process of receiving the R-TWT control information (S317, S318).

[0043] Each STA transmits a low-latency traffic signal to its associated AP (for example, AP1 and AP2) according to the transmission period and type of low-latency traffic signal specified by the R-TWT control information (S319, S320).

[0044] Each AP (e.g., AP1 and AP2) performs reception processing of the low-latency traffic signal (S321, S322), and if no signal error is contained, transmits a response signal (e.g., Acknowledgement (ACK) or BA) to the source STA of the low-latency traffic signal (S323, S324).

[0045] [Configuration Example] A configuration example of the AP and STA according to the first embodiment will be described.

[0046] FIG. 4 is a block diagram showing the configuration of a downlink radio transmitting device (for example, an AP) according to the first embodiment.

[0047] As shown in Figure 4, the downlink radio transmission device includes a receiving antenna 401, a radio receiving unit 402, a preamble demodulation unit 403, a data demodulation unit 404, a data decoding unit 405, an R-TWT control unit 406, a Multi-AP cooperation control unit 407, a scheduling unit 408, a data generation unit 409, a data encoding unit 410, a data modulation unit 411, a preamble generation unit 412, a radio transmission unit 413, and a transmitting antenna 414.

[0048] At least a portion of the preamble demodulation unit 403, data demodulation unit 404, data decoding unit 405, R-TWT control unit 406, Multi-AP cooperation control unit 407, scheduling unit 408, data generation unit 409, data encoding unit 410, data modulation unit 411, and preamble generation unit 412 may constitute a control unit.

[0049] In each configuration, multiple components may be combined into one component. For example, the receiving antenna 401 and the transmitting antenna 414 may be a shared transmitting / receiving antenna, and a directional coupler or a branching filter may be used for sharing. For example, the wireless receiving unit 402 and the wireless transmitting unit 413 may be combined into one wireless transmitting / receiving unit.

[0050] The radio receiving unit 402 receives a signal transmitted from a downstream radio transmitting device (e.g., AP) or a downstream radio receiving device (e.g., STA) via the receiving antenna 401, and performs radio receiving processing such as down-conversion and Analog-to-Digital (A / D) conversion. The radio receiving unit 402 extracts (or divides) a preamble portion (also referred to as a preamble signal) and a data portion (also referred to as a data signal) from the signal after radio receiving processing, and outputs the preamble signal to the preamble demodulation unit 403 and the data signal to the data demodulation unit 404.

[0051] The preamble demodulation unit 403 performs a Discrete Fourier Transform (DFT) or a Fast Fourier Transform (FFT) on the preamble signal output from the radio reception unit 402, and extracts reception control information (e.g., at least one of a frequency bandwidth (BW), a Modulation and Coding Scheme (MCS), and an error correction code) used for demodulating and decoding the data signal. The preamble demodulation unit 403 also performs channel estimation based on a reference signal included in the preamble signal, and derives a channel estimation value. The preamble demodulation unit 403 outputs the reception control information to the data demodulation unit 404 and the data decoding unit 405, and outputs the channel estimation value to the data demodulation unit 404.

[0052] Data demodulation section 404 performs an FFT on the data signal output from radio reception section 402, and demodulates the signal using the reception control information and channel estimation value output from preamble demodulation section 403. Data demodulation section 404 outputs the demodulated data signal to data decoding section 405.

[0053] The data decoding unit 405 decodes the demodulated data signal output from the data demodulation unit 404 using the reception control information output from the preamble demodulation unit 403. The data decoding unit 405 performs error detection on the decoded data signal using a method such as Cyclic Redundancy Check (CRC). If there is no error in the decoded data signal, the data decoding unit 405 outputs the decoded data signal to the R-TWT control unit 406, the multi-AP cooperation control unit 407, and the scheduling unit 408. Error correction may be performed instead of error detection.

[0054] The R-TWT control unit 406 determines the downlink radio transmitting devices and downlink radio receiving devices that can participate in the R-TWT based on the R-TWT capability information contained in the decoded data signal output from the data decoding unit 405, and outputs R-TWT participation availability information to the scheduling unit 408.

[0055] The Multi-AP coordination control unit 407 determines the downlink wireless transmitting devices and downlink wireless receiving devices that can participate in the MAP coordinated transmission based on the capability information regarding the MAP coordinated transmission contained in the decoded data signal output from the data decoding unit 405, and outputs MAP coordinated transmission participation possibility information to the scheduling unit 408.

[0056] The scheduling unit 408 determines scheduling information for R-TWT cooperative transmission (e.g., the R-TWT repetition period for each BSS, the awake / doze period length in power saving mode, the type of low-latency traffic that can be transmitted during R-TWT SP, information on users participating in R-TWT cooperation, information on resources available for each user (e.g., at least one of frequency resources and time resources), MCS, and error correction code) based on the R-TWT participation availability information output from the R-TWT control unit 406 and the MAP cooperative transmission participation availability information output from the Multi-AP cooperation control unit 407.

[0057] Furthermore, when the decoded data signal output from the data decoding unit 405 includes scheduling information for R-TWT coordinated transmission generated by another downlink radio transmitting device, the scheduling unit 408 determines, based on the scheduling information for R-TWT coordinated transmission, scheduling information for a Trigger frame signal that requests the subordinate downlink radio receiving device to transmit a low-latency traffic signal (e.g., user information requesting transmission of a low-latency traffic signal, information on resources available for each user (e.g., at least one of frequency resources and time resources), MCS, and error correction code). The scheduling unit 408 outputs the scheduling information for R-TWT coordinated transmission and the scheduling information for the Trigger frame signal to the data generation unit 409, the data encoding unit 410, the data modulation unit 411, and the preamble generation unit 412.

[0058] The data generation unit 409 generates a data sequence to be transmitted to a downlink radio transmitting device or a downlink radio receiving device based on the scheduling information output from the scheduling unit 408. For example, the data sequence to be transmitted to a downlink radio transmitting device includes at least one of capability information related to MAP cooperative transmission, capability information related to R-TWT, a MAP cooperative transmission join response signal, and control information for R-TWT cooperative transmission. For example, the data sequence to be transmitted to a downlink radio receiving device includes at least one of control information for R-TWT cooperation and a Trigger frame signal that requests the downlink radio receiving device to transmit low-latency traffic. The data generation unit 409 outputs the data sequence to the data encoding unit 410.

[0059] The data encoding unit 410 encodes the data sequence output from the data generation unit 409 based on the scheduling information output from the scheduling unit 408 , and outputs the encoded data signal to the data modulation unit 411 .

[0060] The data modulation unit 411 performs modulation and an inverse discrete Fourier transform (IDFT) or an inverse fast Fourier transform (IFFT) on the coded data signal output from the data coding unit 410 based on the coordination signal scheduling information output from the scheduling unit 408, and outputs the modulated data signal to the radio transmission unit 413.

[0061] The preamble generation unit 412 generates a preamble signal based on the scheduling information output from the scheduling unit 408. The preamble generation unit 412 performs modulation and IFFT processing, and outputs the preamble signal to the radio transmission unit 413.

[0062] The radio transmitting unit 413 generates a radio frame (a packet signal, also called a Physical Layer Convergence Protocol Data Unit (PPDU)) by adding the preamble signal output from the preamble generating unit 412 to the modulated data signal output from the data modulating unit 411. The radio transmitting unit 413 performs radio transmission processing such as Digital-to-Analog (D / A) conversion and up-conversion to a carrier frequency on the radio frame, and transmits the signal after radio transmission processing to a downstream radio transmitting device or a downstream radio receiving device via a transmitting antenna 414.

[0063] FIG. 5 is a block diagram showing the configuration of a downstream radio receiving device (for example, STA) according to the first embodiment.

[0064] As shown in Figure 5, the downlink radio receiving device includes a receiving antenna 501, a radio receiving unit 502, a preamble demodulating unit 503, a data demodulating unit 504, a data decoding unit 505, a power saving mode control unit 506, a transmission signal generating unit 507, a radio transmitting unit 508, and a transmitting antenna 509.

[0065] At least one of the preamble demodulation unit 503, the data demodulation unit 504, the data decoding unit 505, the power saving mode control unit 506, and the transmission signal generation unit 507 may constitute a control unit.

[0066] In each configuration, multiple components may be combined into one component. For example, the receiving antenna 501 and the transmitting antenna 509 may be a shared transmitting / receiving antenna, and a directional coupler or a branching filter may be used for sharing. For example, the wireless receiving unit 502 and the wireless transmitting unit 508 may be combined into one wireless transmitting / receiving unit.

[0067] Radio receiving unit 502 receives a signal transmitted from a downlink radio transmitting device via receiving antenna 501. If the power saving mode information output from power saving mode control unit 506 indicates an awake interval, or if no power saving mode information is output, radio receiving unit 502 performs radio receiving processing such as down-conversion and A / D conversion of the received signal. Radio receiving unit 502 extracts a preamble signal and a data signal from the received signal after radio receiving processing, and outputs the preamble signal to preamble demodulation unit 503 and the data signal to data demodulation unit 504. Furthermore, if the power saving mode information output from power saving mode control unit 506 indicates a doze interval, radio receiving unit 502 suspends radio receiving processing.

[0068] The preamble demodulation unit 503 performs an FFT on the preamble signal output from the radio receiving unit 502 to extract reception control information (e.g., at least one of BW, MCS, and error correction code) used for demodulating and decoding the data signal. The preamble demodulation unit 503 also performs channel estimation based on a reference signal included in the preamble signal to derive a channel estimation value. The preamble demodulation unit 503 outputs the reception control information to the data demodulation unit 504 and data decoding unit 505, and outputs the channel estimation value to the data demodulation unit 504.

[0069] The data demodulation unit 504 performs an FFT on the data signal output from the radio receiving unit 502, demodulates the data signal using the reception control information and channel estimation value output from the preamble demodulation unit 503, and outputs the demodulated data signal to the data decoding unit 505.

[0070] Data decoding unit 505 decodes the demodulated data signal output from data demodulation unit 504 using the reception control information output from preamble demodulation unit 503. Data decoding unit 505 performs error detection on the decoded data signal using a method such as CRC. If there is no error in the decoded data signal, the data decoding unit outputs the decoded data signal to power saving mode control unit 506 and transmission signal generation unit 507. Error correction may be performed instead of error detection.

[0071] The power save mode control unit 506 stores in a buffer information relating to the R-TWT repetition period and the awake / doze interval length of the power save mode in the scheduling information for R-TWT coordinated transmission included in the decoded data signal output from the data decoding unit 505. The power save mode control unit 506 also outputs power save mode information indicating whether the current power save mode is the awake interval or the doze interval to the wireless receiving unit 502 and the transmission signal generating unit 507.

[0072] The transmission signal generation unit 507 generates a data sequence to be transmitted to the downlink radio transmission device based on the decoded data signal output from the data decoding unit 505. For example, the data sequence to be transmitted to the downlink radio transmission device includes capability information related to MAP cooperative transmission, capability information related to R-TWT, and a response signal (ACK or BA). Furthermore, when the power saving mode information output from the power saving mode control unit 506 indicates an awake interval, the transmission signal generation unit 507 generates a data sequence for a low latency traffic signal to be transmitted based on the type of low latency traffic signal in the scheduling information for R-TWT cooperative transmission included in the decoded data signal output from the data decoding unit 505.

[0073] On the other hand, if the power saving mode information output from the power saving mode control unit 506 indicates a doze interval, the transmission signal generation unit 507 suspends the process of generating a transmission signal. Furthermore, if the decoded data signal output from the data decoding unit 505 includes a trigger frame requesting transmission of a low-latency traffic signal, the transmission signal generation unit 507 generates a data sequence to be transmitted in a trigger-based PPDU (TB PPDU) based on the control information included in the trigger frame. The transmission signal generation unit 507 encodes the generated data sequence, allocates it to a predetermined frequency resource, and generates a data signal by performing modulation and IFFT processing. The transmission signal generation unit adds a preamble signal to the data signal to generate a radio frame, and outputs the radio frame to the radio transmission unit 508.

[0074] The radio transmitting unit 508 performs radio transmission processing such as D / A conversion and up-conversion to a carrier frequency on the radio frame output from the transmission signal generating unit 507, and transmits the signal after radio transmission processing to a downlink radio transmitting device via a transmitting antenna 509.

[0075] [Control Method] Next, a method for reporting low latency traffic information related to MAP cooperative transmission using control information related to R-TWT will be described.

[0076] In the first embodiment, the AP notifies low-latency traffic information related to the MAP cooperative transmission in the control information related to the R-TWT. For example, the AP notifies other APs participating in the MAP cooperative transmission of the control information related to the R-TWT, and performs the R-TWT cooperative transmission.

[0077] An example of control information for R-TWT including low-latency traffic information for MAP coordinated transmission is shown in Fig. 6. In Fig. 6, Multi-AP DL TID Bitmap Valid and Multi-AP UL TID Bitmap Valid are notified using part of the Reserved field included in the Traffic Info Control field of the TWT element format.

[0078] When Multi-AP DL / UL TID Bitmap Valid = 1, the Restricted TWT DL / UL TID Bitmap notifies the type of TID that can be transmitted in R-TWT cooperative transmission. That is, the Restricted TWT DL TID Bitmap field contains information indicating the type of TID that can be transmitted in R-TWT cooperative transmission on the downlink (from the AP to the STA), and the Restricted TWT UL TID Bitmap field contains information indicating the type of TID that can be transmitted in R-TWT cooperative transmission on the uplink (from the STA to the AP).

[0079] In detail, the Multi-AP DL TID Bitmap Valid subfield includes information indicating whether information indicating the type of TID that can be transmitted in downlink R-TWT coordinated transmission (for example, the Restricted TWT DL TID Bitmap field) is included in the TWT element, and the Multi-AP UL TID Bitmap Valid subfield includes information indicating whether information indicating the type of TID that can be transmitted in uplink R-TWT coordinated transmission (for example, the Restricted TWT UL TID Bitmap field) is included in the TWT element. Each bit in the Restricted TWT DL TID Bitmap field and / or the Restricted TWT UL TID Bitmap field corresponds to a TID value and may indicate whether the corresponding TID can be transmitted in R-TWT coordinated transmission.

[0080] The field names and subfield names are not limited to these. Furthermore, instead of a bitmap indicating the type of TID, the maximum or minimum value of the TID may be notified. Furthermore, instead of the TID, information indicating the type of access category (AC) that can be transmitted in R-TWT cooperative transmission (for example, bitmaps corresponding to the access categories AC_VO, AC_VI, AC_BE, and AC_BK) may be included in the TWT element.

[0081] When Multi-AP DL / UL TID Bitmap Valid = 0, the type of TID usable for R-TWT cooperative transmission is not reported. Also, the combination of reporting 1 in both the DL TID Bitmap Valid and Multi-AP DL TID Bitmap Valid subfields is prohibited. Similarly, the combination of reporting 1 in both the UL TID Bitmap Valid and Multi-AP UL TID Bitmap Valid subfields is prohibited.

[0082] An example of the operation of R-TWT cooperative transmission is shown in Figures 7 and 8. In this case, it is assumed that BSS1 includes AP1 and STA1, and BSS2 includes AP2 and STA2.

[0083] FIG. 7 shows an example of the operation of R-TWT cooperative transmission when different transmission timings are assigned to each BSS.

[0084] First, the beacon signal transmitted by AP1 includes a TWT element for each BSS, and notifies, for example, the period of R-TWT SP for each BSS and the type of low latency traffic (S701).

[0085] Then, each AP (each BSS) notifies the associated STA of the R-TWT SP period, which differs for each BSS, by the TWT element of the beacon signal (S702, S703). In addition, the TWT element for each BSS has Multi-AP DL / UL TID Bitmap Valid = 1, and different types of low latency traffic signals may be notified.

[0086] After transmitting the TWT element for each BSS, each AP notifies its subordinate STAs of the R-TWT control information obtained from the TWT element for each BSS using Basic TF during the awake period (S704, S707).

[0087] Each STA (for example, STA1 and STA2) transmits a UL low latency traffic signal to the AP to which it belongs (S705, S708).

[0088] Each AP (e.g., AP1 and AP2) performs reception processing of the UL low latency traffic signal, and if no signal errors are found, transmits a response signal (e.g., BA) to the STA that transmitted the UL low latency traffic signal (S706, S709).

[0089] FIG. 8 shows an example of the operation of R-TWT cooperative transmission when a transmission timing common to all BSSs is assigned.

[0090] First, the beacon signal transmitted by AP1 includes a BSS-common TWT element, and notifies, for example, the period of the BSS-common R-TWT SP and the type of low-latency traffic signal (S801).

[0091] Thereafter, each AP (each BSS) notifies the associated STA of the period of the R-TWT SP common to the BSSs by using the TWT element of the beacon signal (S802, S803).

[0092] Also, information about available frequency resources during an R-TWT SP may be reported for each BSS. Also, the AP may perform MAP coordinated transmission (e.g., JT, C-BF, or C-SR) including low-latency traffic signals within a common R-TWT SP.

[0093] After transmitting the TWT element for each BSS (S802, S803), each AP notifies its subordinate STAs of the R-TWT control information obtained from the TWT element for each BSS using Basic TF during the awake period (S804, S805).

[0094] Each STA (for example, STA1 and STA2) transmits a UL low latency traffic signal to the AP to which it belongs (S806, S807). The UL low latency traffic signal transmitted by each STA may be a MAP coordinated transmission.

[0095] Each AP (e.g., AP1 and AP2) performs reception processing of the UL low latency traffic signal, and if no signal errors are found, transmits a response signal (e.g., BA) to the STA that transmitted the UL low latency traffic signal (S808, S809).

[0096] During the R-TWT SP period (i.e., the awake period), each AP may transmit a non-low latency traffic signal using a frequency resource other than the frequency resource notified in the R-TWT control information. Furthermore, outside the R-TWT SP period (i.e., the doze period), the AP may communicate with a STA that has not notified R-TWT control information in a TWT element. For example, the AP may transmit a TWT element to a STA to notify it of Individual TWT control information (at least one of Individual TWT period information and frequency resource information), and the AP and the STA may communicate according to the Individual TWT control information.

[0097] The control method of embodiment 1 allows the AP to control the R-TWT for each BSS. In the case of Fig. 7, by assigning different transmission timings to each BSS, it is possible to avoid interference that UL low latency traffic signals receive from signals of other BSSs, thereby improving communication quality. In addition, in the case of Fig. 8, by assigning transmission timings common to all BSSs and notifying the types of low latency traffic signals that can be commonly transmitted, it is possible to realize MAP coordinated transmission including UL low latency traffic signals during the R-TWT period.

[0098] The AP may transmit a signal including a DL low-latency traffic signal, and the STA may receive the signal including the DL low-latency traffic signal.

[0099] [Embodiment 2] In embodiment 2, multiple APs and multiple STAs cooperate to notify low-latency traffic information using non-R-TWT control information. Furthermore, the multiple APs and multiple STAs transmit low-latency traffic signals based on the low-latency traffic information. Below, as an example, a method will be described in which two APs transmit and receive low-latency traffic information related to low-latency traffic signals between the APs using non-R-TWT control information, the AP transmits a DL low-latency traffic signal to a STA, and the STA receives the DL low-latency traffic signal.

[0100] The STA may transmit a signal including a UL low latency traffic signal, and the AP may receive the signal including the UL low latency traffic signal.

[0101] An example of the operation of an AP and a STA according to embodiment 2 will now be described. Fig. 9 is a sequence diagram for controlling MAP coordinated transmission during an R-TWT period among multiple APs, as an example of embodiment 2. In this case, it is assumed that BSS1 includes AP1 and STA1, and BSS2 includes AP2 and STA2.

[0102] Each STA (e.g., STA1 and STA2) transmits a beacon signal including capability information related to MAP cooperative transmission to an AP belonging to the common BSS (S901, S902). The signal including the capability information is not limited to a beacon signal. For example, the capability information related to MAP cooperative transmission may be included in an association signal transmitted from the STA to the AP.

[0103] Each AP performs a receiving process for the beacon signal transmitted from the STA, and stores capability information related to MAP cooperative transmission in a buffer (S903, S904).

[0104] Each AP (for example, AP1 and AP2) transmits a beacon signal including capability information regarding MAP cooperative transmission to other APs (S905, S907).

[0105] Each AP performs reception processing of the beacon signals transmitted from the other APs and stores capability information related to MAP cooperative transmission in a buffer (S906, S908).

[0106] AP1 acquires the TXOP and acts as a Sharing AP that initiates MAP cooperative transmission.

[0107] AP1 transmits a multi-AP cooperative transmission participation request signal to AP2 (S909).

[0108] AP2 performs a receiving process for the Multi-AP cooperative transmission participation request signal (S910), determines whether to participate in the MAP cooperative transmission based on its capability information regarding the MAP cooperative transmission, and transmits a Multi-AP cooperative transmission participation response signal to AP1 (S911).

[0109] AP1 receives the Multi-AP cooperative transmission participation response signal (S912) and transmits a low-latency traffic control signal to APs and STAs that can participate in the MAP cooperative transmission (S913). The low-latency traffic control signal includes information about the type of low-latency traffic signal that can be transmitted in the MAP cooperative transmission.

[0110] The AP and STA that have received the low-latency traffic control signal store information about the type of low-latency traffic signal that can be transmitted by MAP cooperative transmission in a buffer (S914).

[0111] AP1 transmits a multi-AP cooperative transmission control signal to AP2 (S915). The multi-AP cooperative transmission control signal includes at least one of MAP cooperative transmission type information, destination information for the MAP cooperative transmission signal, resource information available to each AP (e.g., at least one of frequency resource information and time resource information), information on weighting of amplitude and phase in cooperative transmission (also called steering, spatial mapping, or transmission precoding), transmission power information, and transmission timing information.

[0112] Upon receiving the multi-AP coordinated transmission control signal, AP2 stores the information of the multi-AP coordinated transmission control signal in a buffer (S916).

[0113] Each AP (e.g., AP1 and AP2) transmits a MAP cooperative transmission signal including a DL low-latency traffic signal to the STA in accordance with the transmission timing and resource information indicated in the Multi-AP cooperative transmission control signal, and the type of low-latency traffic signal indicated in the low-latency traffic control signal (S917, S918).

[0114] Each STA (e.g., STA1 and STA2) performs reception processing of the MAP cooperative transmission signal including the DL low-latency traffic signal (S919, S920), and if no signal error is found, transmits a response signal (e.g., ACK or BA) to the AP that transmitted the MAP cooperative transmission signal (S921, S922).

[0115] [Configuration Example] A configuration example of the AP and STA according to the second embodiment will be described.

[0116] FIG. 10 is a block diagram showing a configuration of a downlink radio transmitting device (for example, an AP) according to the second embodiment.

[0117] As shown in Figure 10, the downlink radio transmitting device includes a receiving antenna 1001, a radio receiving unit 1002, a preamble demodulation unit 1003, a data demodulation unit 1004, a data decoding unit 1005, a low-latency traffic control unit 1006, a multi-AP cooperation control unit 1007, a scheduling unit 1008, a data generation unit 1009, a data encoding unit 1010, a data modulation unit 1011, a preamble generation unit 1012, a radio transmitting unit 1013, and a transmitting antenna 1014.

[0118] At least one of the preamble demodulation unit 1003, data demodulation unit 1004, data decoding unit 1005, low-latency traffic control unit 1006, multi-AP cooperation control unit 1007, scheduling unit 1008, data generation unit 1009, data encoding unit 1010, data modulation unit 1011, and preamble generation unit 1012 may constitute a control unit.

[0119] Each configuration may be configured such that multiple components are combined into one component. For example, the receiving antenna 1001 and the transmitting antenna 1014 may be a shared transmitting / receiving antenna, and a directional coupler or a branching filter may be used for sharing. For example, the wireless receiving unit 1002 and the wireless transmitting unit 1013 may be combined into one wireless transmitting / receiving unit.

[0120] The radio receiving unit 1002 receives a signal transmitted from a downlink radio transmitting device or a downlink radio receiving device (e.g., STA) via the receiving antenna 1001, and performs radio receiving processing such as down-conversion and A / D conversion. The radio receiving unit 1002 extracts (or divides) a preamble portion (also called a preamble signal) and a data portion (also called a data signal) from the signal after radio receiving processing, and outputs the preamble signal to the preamble demodulation unit 1003 and the data signal to the data demodulation unit 1004.

[0121] The preamble demodulation unit 1003 performs an FFT on the preamble signal output from the radio receiving unit 1002 to extract reception control information (e.g., at least one of BW, MCS, and error correction code) used for demodulating and decoding the data signal. The preamble demodulation unit 1003 also performs channel estimation based on a reference signal included in the preamble signal to derive a channel estimation value. The preamble demodulation unit 1003 outputs the reception control information to the data demodulation unit 1004 and data decoding unit 1005, and outputs the channel estimation value to the data demodulation unit 1004.

[0122] Data demodulation section 1004 performs FFT on the data signal output from radio reception section 1002, and demodulates the signal using the reception control information and channel estimation value output from preamble demodulation section 1003. Data demodulation section 1004 outputs the demodulated data signal to data decoding section 1005.

[0123] The data decoding unit 1005 decodes the demodulated data signal output from the data demodulation unit 1004 using the reception control information output from the preamble demodulation unit 1003. The data decoding unit 1005 performs error detection on the decoded data signal using a method such as CRC. If there is no error in the decoded data signal, the data decoding unit 1005 outputs the decoded data signal to the low-latency traffic control unit 1006, the multi-AP cooperation control unit 1007, and the scheduling unit 1008. Error correction may be performed instead of error detection.

[0124] The low-latency traffic control unit 1006 stores the low-latency traffic information contained in the decoded data signal output from the data decoding unit 1005 in a buffer, and outputs to the scheduling unit 1008, as low-latency traffic information, information on downlink radio transmitting devices and downlink radio receiving devices capable of transmitting and receiving low-latency traffic signals, and the type of low-latency traffic signal that can be transmitted.

[0125] The Multi-AP coordination control unit 1007 determines the downlink wireless transmitting devices and downlink wireless receiving devices that can participate in the MAP coordinated transmission based on the capability information regarding the MAP coordinated transmission contained in the decoded data signal output from the data decoding unit 1005, and outputs information on whether or not to participate in the MAP coordinated transmission to the scheduling unit 1008.

[0126] The scheduling unit 1008 determines scheduling information related to MAP cooperative transmission (e.g., the type of low-latency traffic signal that can be transmitted in MAP cooperative transmission, the type of MAP cooperative transmission, information on users participating in MAP cooperative transmission, information on resources available for each user (e.g., at least one of frequency resources and time resources), MCS, and error correction code) based on the low-latency traffic information output from the low-latency traffic control unit 1006 and the MAP cooperative transmission participation information output from the Multi-AP cooperation control unit 1007.

[0127] Furthermore, when the decoded data signal output from the data decoding unit 1005 includes scheduling information related to MAP cooperative transmission generated by another downlink wireless transmitting device, the scheduling unit 1008 determines scheduling information (e.g., user information requesting transmission of a low-latency traffic signal, information on resources available for each user (e.g., at least one of frequency resources and time resources), MCS, and error correction code) of a low-latency traffic signal to be transmitted to a subordinate downlink wireless receiving device based on the scheduling information related to MAP cooperative transmission. The scheduling unit 1008 outputs the scheduling information related to MAP cooperative transmission and the scheduling information of the low-latency traffic signal to the data generation unit 1009, the data encoding unit 1010, the data modulation unit 1011, and the preamble generation unit 1012.

[0128] The data generation unit 1009 generates a data sequence to be transmitted to a downlink radio transmitting device or a downlink radio receiving device based on the scheduling information (scheduling information related to MAP cooperative transmission and scheduling information for a low-latency traffic signal) output from the scheduling unit 1008. For example, the data sequence to be transmitted to a downlink radio transmitting device includes at least one of capability information related to MAP cooperation, a MAP cooperative transmission join request signal, a MAP cooperative transmission join response signal, a low-latency traffic control signal related to MAP cooperative transmission, and a MAP cooperative transmission control signal. For example, the data sequence to be transmitted to a downlink radio receiving device includes a low-latency traffic control signal related to MAP cooperative transmission and a low-latency traffic signal addressed to a downlink radio receiving device. The data generation unit 1009 outputs the data sequence to the data encoding unit 1010.

[0129] The data encoding unit 1010 encodes the data sequence output from the data generation unit 1009 based on the scheduling information output from the scheduling unit, and outputs the encoded data signal to the data modulation unit 1011 .

[0130] The data modulation unit 1011 performs modulation and IFFT on the coded data signal output from the data coding unit 1010 based on the scheduling information output from the scheduling unit 1008, and outputs the modulated data signal to the radio transmission unit 1013.

[0131] The preamble generation unit 1012 generates a preamble signal based on the scheduling information output from the scheduling unit 1008. The preamble generation unit 1012 performs modulation and IFFT processing, and outputs the preamble signal to the radio transmission unit 1013.

[0132] The radio transmitting unit 1013 generates a radio frame (also called a packet signal) by adding the preamble signal output from the preamble generating unit 1012 to the modulated data signal output from the data modulating unit 1011. The radio transmitting unit 1013 performs radio transmission processing such as D / A conversion and up-conversion to a carrier frequency on the radio frame, and transmits the signal after the radio transmission processing to a downstream radio transmitting device or a downstream radio receiving device via a transmitting antenna 1014.

[0133] FIG. 11 is a block diagram showing the configuration of a downstream radio receiving device (for example, STA) according to the second embodiment.

[0134] As shown in FIG. 11, the downlink radio receiving device includes a receiving antenna 1101, a radio receiving unit 1102, a preamble demodulating unit 1103, a data demodulating unit 1104, a data decoding unit 1105, a low-latency traffic control unit 1106, a transmission signal generating unit 1107, a radio transmitting unit 1108, and a transmitting antenna 1109.

[0135] At least one of the preamble demodulator 1103, the data demodulator 1104, the data decoder 1105, the low-delay traffic controller 1106, and the transmission signal generator 1107 may constitute a controller.

[0136] In each configuration, multiple components may be combined into one component. For example, the receiving antenna 1101 and the transmitting antenna 1109 may be a shared transmitting / receiving antenna, and a directional coupler or a branching filter may be used for sharing. For example, the wireless receiving unit 1102 and the wireless transmitting unit 1108 may be combined into one wireless transmitting / receiving unit.

[0137] Radio receiving section 1102 receives a signal transmitted from a downlink radio transmitting device via receiving antenna 1101. Radio receiving section 1102 performs radio receiving processing such as down-conversion and A / D conversion of the received signal. Radio receiving section 1102 extracts a preamble signal and a data signal from the received signal after radio receiving processing, and outputs the preamble signal to preamble demodulation section 1103 and the data signal to data demodulation section 1104.

[0138] The preamble demodulation unit 1103 performs an FFT on the preamble signal output from the radio receiving unit 1102 and extracts reception control information (e.g., at least one of BW, MCS, and error correction code) used for demodulating and decoding the data portion. The preamble demodulation unit 1103 also performs channel estimation based on a reference signal included in the preamble signal to derive a channel estimation value. The preamble demodulation unit 1103 outputs the reception control information to the data demodulation unit 1104 and data decoding unit 1105, and outputs the channel estimation value to the data demodulation unit 1104.

[0139] The data demodulation unit 1104 performs an FFT on the data signal output from the radio receiving unit 1102, demodulates the data signal using the reception control information and channel estimation value output from the preamble demodulation unit 1103, and outputs the demodulated data signal to the data decoding unit 1105.

[0140] The data decoding unit 1105 decodes the demodulated data signal output from the data demodulation unit 1104 using the reception control information output from the preamble demodulation unit 1103. The data decoding unit 1105 performs error detection on the decoded data signal using a method such as CRC. If there is no error in the decoded data signal, the data decoding unit outputs the decoded data signal to the low-delay traffic control unit 1106 and the transmission signal generation unit 1107. Error correction may be performed instead of error detection.

[0141] The low-delay traffic control unit 1106 stores the low-delay traffic information included in the decoded data signal output from the data decoding unit 1105 in a buffer, and outputs the type of transmittable low-delay traffic signal to the transmission signal generation unit 1107 .

[0142] The transmission signal generation unit 1107 generates a data sequence to be transmitted to the downlink wireless transmission device based on the decoded data signal output from the data decoding unit 1105. For example, the data sequence to be transmitted to the downlink wireless transmission device includes at least one of capability information related to MAP cooperative transmission and a response signal (ACK or BA) to a signal including a low-latency traffic signal transmitted from the downlink wireless transmission device. The data sequence to be transmitted to the downlink wireless transmission device also includes a data sequence of a low-latency traffic signal to be transmitted to the downlink wireless transmission device, determined based on the type of low-latency traffic signal permitted for transmission in the low-latency traffic information output from the low-latency traffic control unit 1106. The transmission signal generation unit 1107 encodes the generated data sequence, allocates it to a predetermined frequency resource, and generates a data signal by performing modulation and IFFT processing. The transmission signal generation unit 1107 adds a preamble signal to the data signal to generate a radio frame, and outputs the radio frame to the radio transmission unit 1108.

[0143] The radio transmitting unit 1108 performs radio transmission processing such as D / A conversion and upconversion to a carrier frequency on the radio frame output from the transmission signal generating unit 1107, and transmits the signal after radio transmission processing to a downlink radio transmitting device via the transmitting antenna 1109.

[0144] As described in the first and second embodiments, the AP of the present disclosure notifies other APs of low latency traffic information.

[0145] A low-delay traffic signal is, for example, at least one of a traffic signal with priority (e.g., transmission availability information or user priority), a traffic signal with a large amount stored in a buffer (buffer queue size), a traffic signal with a small allowable delay (delay bound), and a traffic signal with a high required quality (MAC Service Data Unit (MSDU) delivery ratio).

[0146] The low-latency traffic information includes, for example, at least one of TID bitmap information for determining whether transmission is possible, buffer information for each TID (Buffer Status Report (BSR)), and QoS information.

[0147] In the first embodiment, the AP notifies low-latency traffic information related to MAP cooperative transmission in a frame including R-TWT control information, such as a TWT element (e.g., FIG. 6), or in a beacon signal or association signal including capability information related to MAP cooperative transmission and capability information related to R-TWT.

[0148] In the second embodiment, the AP notifies low-latency traffic information related to MAP cooperative transmission using non-R-TWT control information. Notification examples for notifying low-latency traffic information related to MAP cooperative transmission using non-R-TWT control information are shown below. In the second embodiment, by using one of the notification examples below, the AP notifies low-latency traffic information related to MAP cooperative transmission between APs, thereby making it possible to determine low-latency traffic signals that can be transmitted using MAP cooperative transmission.

[0149] [Notification Example 1 of Second Embodiment] In notification example 1, low latency traffic information related to MAP cooperative transmission is notified using TID.

[0150] For example, low-latency traffic information related to MAP cooperative transmission may be notified in an element (or frame, subframe: hereinafter referred to as a management signal) different from the TWT element, as shown in FIG. 12 . As an example, the management signal in FIG. 12 may be referred to as a Multi-AP Traffic element. An AP may transmit the management signal in FIG. 12 by including it in a management frame for setting up or starting Multi-AP operation (e.g., a Multi-AP Setup frame (not shown), a Multi-AP Reconfiguration frame (not shown), or the Multi-AP cooperative transmission participation request / response signal in FIG. 9 ). The Multi-AP DL TID bitmap and Multi-AP UL TID bitmap included in the management signal in FIG. 12 indicate, if each bit = 1, that the corresponding TID can be transmitted in MAP cooperative transmission, and, if each bit = 0, that the corresponding TID cannot be transmitted in MAP cooperative transmission.

[0151] Alternatively, the low-latency traffic information related to MAP cooperative transmission may be notified in a trigger frame. The low-latency traffic information related to MAP cooperative transmission notified in a trigger frame may be changed in the MAP cooperative transmission method (multi-AP sequence).

[0152] Request information for a low-latency traffic signal related to MAP cooperative transmission may be transmitted in a control signal for MAP cooperative transmission (e.g., Multi-AP sequence = negotiation). Fig. 13 shows an example of signaling in which low-latency traffic information related to MAP cooperative transmission is transmitted in a control signal for MAP cooperative transmission. The Multi-AP request DL TID bitmap and Multi-AP request UL TID bitmap included in Fig. 13 indicate that if each bit = 1, it is desired to transmit the corresponding TID by MAP cooperative transmission, and if each bit = 0, it is desired not to transmit the corresponding TID by MAP cooperative transmission.

[0153] Low-latency traffic information usable in MAP coordinated transmission may be signaled in a transmission start notification signal for MAP coordinated transmission (e.g., Multi-AP Sequence = JT / C-BF / C-SR / C-OFDMA). FIG. 14 shows an example of signaling in which low-latency traffic information related to MAP coordinated transmission is signaled in a transmission start notification signal for MAP coordinated transmission. The Multi-AP TID bitmap included in FIG. 14 signals TIDs usable in the MAP coordinated transmission method signaled in the Multi-AP sequence. For example, if each bit of the Multi-AP TID bitmap is 1, it indicates that the corresponding TID can be transmitted using the notified MAP coordinated transmission method, and if each bit is 0, it indicates that the corresponding TID cannot be transmitted using the notified MAP coordinated transmission. In FIG. 14, DL / UL is also specified in the Multi-AP sequence, so one bitmap for DL ​​or UL is shown, but two bitmaps, one for DL ​​and one for UL, may also be used.

[0154] An example of operation when low-latency traffic information related to MAP cooperative transmission is notified by a management signal is shown in Fig. 15. Note that Fig. 15 shows an example in which an Association Request signal and an Association Response signal are used as management signals, but the management signal is not limited to this and may be of another frame type.

[0155] 15 shows an example in which three APs use a management signal to determine low-latency traffic information (e.g., TID) to be used in MAP cooperative transmission. In FIG. 15, APs 1-3 are included in a cooperative group (e.g., an AP candidate set) consisting of multiple APs, and AP 1 acts as a Coordination AP that takes the lead in controlling the cooperative group.

[0156] In S1501, AP2 and AP3 transmit Association Request signals to AP1 to join the cooperative group controlled by AP1. At this time, AP2 and AP3 use the signaling of Fig. 12 to transmit the Association Request signals to AP1, including low-latency traffic information (e.g., TID) of the low-latency traffic signals to be used in the MAP cooperative transmission.

[0157] At S1502, AP1 determines low-latency traffic information (e.g., TID) of low-latency traffic signals to be used in the coordinated group based on low-latency traffic information (e.g., TID) of low-latency traffic signals to be used in MAP coordinated transmission, which is included in the transmission signals of AP2 and AP3. AP1 notifies AP2 and AP3 of the low-latency traffic information (e.g., TID) of low-latency traffic signals that can be used in the coordinated group by including the information in an Association Response signal using the signaling of FIG.

[0158] In S1503, AP2, which acquires the TXOP and operates as a Sharing AP, notifies AP3, which is a Shared AP and forms a virtual BSS with AP2, of request information for low-latency traffic information (e.g., TID) of the low-latency traffic signal to be used in MAP cooperative transmission, using the signaling shown in Fig. 13. The virtual BSS refers to the cooperative group that actually performs MAP cooperative transmission.

[0159] In S1504, AP3 receives request information for low-latency traffic information (e.g., TID) of the low-latency traffic signal to be used in MAP cooperative transmission, and responds with the low-latency traffic information (e.g., TID) of the low-latency traffic signal to be used in MAP cooperative transmission using the signaling of Figure 12.

[0160] In S1505, AP2 determines a MAP cooperative transmission method and low-latency traffic information (e.g., TID) that can be used in MAP cooperative transmission based on the low-latency traffic information (e.g., TID) of the low-latency traffic signal that AP2 wishes to use in MAP cooperative transmission received from AP3, and notifies AP3 of the method using the signaling of Figure 14.

[0161] For the low-latency traffic information (e.g., TID) notified from the Coordination AP in S1502, more detailed low-latency traffic information (e.g., TID) can be determined through communication between the Sharing AP and the Shared AP constituting the Virtual BSS (S1503, S1504). By notifying low-latency traffic information between APs using these methods, it is possible to determine low-latency traffic information (e.g., TID) that can be transmitted by MAP cooperative transmission.

[0162] [Notification Example 2 of Second Embodiment] In notification example 2, low latency traffic information related to MAP cooperative transmission is notified in buffer information.

[0163] For example, low-latency traffic information related to MAP cooperative transmission may be notified using the BSR format shown in Fig. 16. For example, the buffer traffic volume of the AC notified by the Access Category Index (ACI) High included in the signaling of Fig. 16 is notified by the Queue Size High.

[0164] FIG. 17 shows an example of operation when low-delay traffic information related to MAP cooperative transmission is notified in buffer information.

[0165] In order to send and receive low-latency traffic information related to MAP cooperative transmission, AP1, which is a Sharing AP, may request the transmission of a BSR by sending a BSR Polling (BSRP) to AP2, for example, with the destination information of AP2 included in the MAC header of the BSRP or in AID12 of the user information (S1701).

[0166] AP2, which has received the BSRP, transmits a BSR to AP1 (S1702).

[0167] Based on the BSR notified from AP2, AP1 transmits to AP2 the MAP cooperative transmission method and low-latency traffic information that can be transmitted by the MAP cooperative transmission (S1703).

[0168] Furthermore, low-latency traffic information related to MAP cooperative transmission (the queue size for each TID to be transmitted in MAP cooperative transmission) may be notified by combining the TID bitmap and BSR. An example of this signaling is shown in FIG. 18. In FIG. 18, if each bit in the Multi-AP TID Bitmap is set to 1, the buffer traffic volume for the TID corresponding to that bit is notified by the Queue Size of TID n (n corresponds to the TID). Furthermore, if each bit in the Multi-AP TID Bitmap is set to 0, the buffer traffic volume for the TID corresponding to that bit is not notified.

[0169] [Notification Example 3 of Second Embodiment] In Notification Example 3, low-latency traffic information related to MAP cooperative transmission is notified using QoS information. The QoS information includes at least one of priority (e.g., user priority), maximum allowable delay (delay bound), quality information (MSDU delivery ratio), etc.

[0170] For example, low-latency traffic information related to MAP cooperative transmission may be notified by the QoS Characteristics element shown in Fig. 19. For example, part of the Reserved field included in the Control Info is used as the MAP QoS Info, and whether the QoS information is related to MAP cooperative transmission is notified. For example, when MAP QoS Info = 1, the information notified by the QoS Characteristics element (e.g., TID, User Priority, Delay Bound, MSDU Delivery Ratio, etc.) is QoS information related to MAP cooperative transmission, and when MAP QoS Info = 0, the information notified by the QoS Characteristics element is QoS information related to non-MAP cooperative transmission.

[0171] Furthermore, for example, low-latency traffic information related to MAP cooperative transmission is notified by the traffic specification (TSPEC) element shown in FIG. 20 . For example, part of the Reserved included in Traffic Stream (TS) Info is used as MAP TS info to notify whether it is QoS information related to MAP cooperative transmission. For example, when MAP TS Info = 1, the information notified by the TSPEC element (e.g., TID, User Priority, Delay Bound, etc.) may be QoS information related to MAP cooperative transmission. Using the Traffic Type included in TS Info, when Traffic Type = 1, it may be notified that the traffic signal is a periodic traffic signal related to MAP cooperative transmission, and when Traffic Type = 0, it may be notified that the traffic signal is an aperiodic traffic signal related to MAP cooperative transmission.

[0172] Also, for example, when MAP TS Info = 0, the information notified by the TSPEC element may be QoS information related to non-MAP cooperative transmission.

[0173] Also, for example, low latency traffic information related to MAP cooperative transmission may be notified using the traffic classification (TCLAS) element shown in Fig. 21. For example, the priority and AC related to MAP cooperative transmission may be notified as shown in Table 2 using part of the reserved user priority included in the TCLAS element, User Priority = 12 to 23.

[0174]

[0175] Furthermore, for example, low latency traffic information related to MAP cooperative transmission may be notified using the Intra-Access Category element shown in Fig. 22. For example, part of the Reserved included in the Intra Access Priority may be set as the MAP User Priority, and the MAP User Priority may be used to notify whether the QoS information is related to MAP cooperative transmission. For example, when MAP User Priority = 1, the User priority notified using the Intra-Access Category element may indicate the priority of the stream in the AC related to MAP cooperative transmission, and when MAP User Priority = 0, the User priority notified using the Intra-Access Category element may indicate the priority of the stream in the AC related to non-MAP cooperative transmission.

[0176] FIG. 23 shows an example of operation when low-latency traffic information related to MAP cooperative transmission is notified using a TSPEC element.

[0177] AP1, which is the Sharing AP, sends an add Traffic Stream (ADDTS) Request to AP2, which is the Shared AP, containing a TSPEC element with QoS information set for transmitting a low-latency traffic signal in the desired MAP cooperative transmission (S2301).

[0178] AP2 receives the ADDTS Request and notifies the AP2 of whether or not it is acceptable to the MAP coordinated transmission described in the TSPEC by using an ADDTS Response (S2302).

[0179] Upon receiving the ADDTS Response, the AP1 transmits to the AP2 a MAP Trigger frame including control information (for example, at least one of MCS, error correction method, etc.) that satisfies the QoS information notified by the TSPEC element (S2303).

[0180] AP1 and AP2 perform MAP coordinated transmission in accordance with the control information notified in the MAP Trigger frame (S2304, S2305).

[0181] The AP1 transmits a delete TS (DELTS) signal to notify the end of communication that satisfies the QoS information notified by the TSPEC element (S2306).

[0182] Although FIG. 23 shows an example in which the Sharing AP transmits an ADDTS Request to the Shared AP, the Shared AP may transmit an ADDTS Request to the Sharing AP.

[0183] FIG. 24 shows an example of operation when low-latency traffic information related to MAP cooperative transmission is notified using a control signal of the Stream Classification Service (SCS).

[0184] AP1, which is a Sharing AP, transmits an SCS Request signal including QoS information for transmitting low-latency traffic in the desired MAP cooperative transmission to AP2, which is a Shared AP (S2401).

[0185] For example, AP1 notifies an SCS Request by including an SCS Descriptor List as shown in Fig. 25. For example, the TCLAS element included in the SCS Descriptor List may be used to notify the User Priority for MAP cooperative transmission as shown in Fig. 21. Furthermore, the Intra-Access Category priority element in the SCS Descriptor List may be used to notify the priority of streams within the AC for MAP cooperative transmission as shown in Fig. 22. Furthermore, the SCS Request may include a QoS Characteristics element to notify QoS information for MAP cooperative transmission.

[0186] Upon receiving the SCS Request, the AP2 notifies the AP1 of whether or not it is willing to accept the MAP coordinated transmission, which is included in the SCS Request signal, in an SCS Response (S2402).

[0187] Upon receiving the SCS Request, the AP1 transmits to the AP2 a MAP Trigger frame including control information that satisfies the QoS information notified in the SCS Request (S2403).

[0188] AP1 and AP2 perform MAP coordinated transmission in accordance with the control information notified in the MAP Trigger frame (S2404, S2405).

[0189] The AP1 notifies the end of SCS transmission that satisfies the QoS information notified in the SCS Request by using an SCS Response (S2406).

[0190] While Fig. 24 shows an example in which the Sharing AP transmits an SCS Request to the Shared AP, the Shared AP may also transmit the SCS Request to the Sharing AP. Furthermore, a series of SCS transmissions starting with the SCS Request may be performed during a QoS communication period using a TSPEC element. For example, the SCS Request may be transmitted after transmitting an ADDTS Response to an ADDTS Request. Furthermore, the QoS Characteristics element may be included in the TWT element related to R-TWT cooperation shown in Fig. 6 to notify QoS information related to the transmission signal during the R-TWT SP period.

[0191] [Control Method 1 of Second Embodiment] A method in which an AP determines low latency traffic information that can be used in MAP cooperative transmission based on low latency traffic information of other terminals (APs and STAs) will be described.

[0192] For example, APs that control MAP cooperative transmission (Coordination AP and Sharing AP) use low-latency traffic information of other APs to determine low-latency traffic information that can be used in MAP cooperative transmission.

[0193] Specifically, the low-latency traffic information available for MAP cooperative transmission may be determined by the logical sum (OR) or logical product (AND) of the TID bitmaps of each AP. Alternatively, the low-latency traffic information available for MAP cooperative transmission may be determined based on the total amount of buffer traffic for each TID.

[0194] In addition, an AP may determine low-latency traffic information to be transmitted to other APs based on the low-latency traffic information of the STAs. For example, an AP may derive a BSR for each BSS (hereinafter referred to as "BSS BSR") based on the BSRs of all STAs under its control and notify other APs of the BSR.

[0195] An example of a BSS BSR is shown in Figure 26. The BSS BSR includes a BSR for the AP in the DL MAP BSR, and a Number of STAs indicating the number of STAs under the AP and a BSR for each STA in the UL MAP BSR. The DL / UL MAP BSR included in the BSS BSR may use signaling that combines a TID bitmap and a BSR, as shown in Figure 18. The DL MAP BSR included in the BSS BSR may notify a single BSR of the total amount of buffer traffic for all STAs, or may notify a single BSR of the total amount of buffer traffic for STAs participating in a specific MAP cooperative transmission (or STAs not participating).

[0196] An example of the operation of control method 1 of embodiment 2 is shown in FIG.

[0197] In Figure 27, each AP (e.g., AP1 and AP2) sends a BSRP to its subordinate STAs (e.g., STA1 and STA2) (S2701, S2703), and each STA (e.g., STA1 and STA2) sends a BSR to the AP to which it belongs (S2702, S2704).

[0198] Having acquired the TXOP, AP1 becomes the Sharing AP and transmits a BSRP to AP2, requesting the transmission of a BSS BSR for BSS2 to which AP2 belongs (S2705).

[0199] Upon receiving the BSRP, AP2 transmits a BSS BSR to AP1 (S2376).

[0200] Based on the BSS BSR received from AP2, AP1 determines the low-latency traffic information to be used in the MAP cooperative transmission of AP1 and AP2, and notifies AP2 of the transmittable low-latency traffic information along with the MAP cooperative transmission method in a MAP Trigger frame (S2707).

[0201] According to the control method 1 of the second embodiment, the low latency traffic information to be used in the MAP cooperative transmission can be determined by negotiation between the APs based on the BSRs of the APs and STAs belonging to other BSSs. In particular, in the UL MAP cooperative transmission, the low latency traffic information to be transmitted by the STA can be appropriately determined.

[0202] [Control Method 2 of Second Embodiment] In control method 2 of the second embodiment, the AP controls MAP cooperative transmission based on low-latency traffic information.

[0203] In control method 2-1, the controlling AP (e.g., Sharing AP) for MAP cooperative transmission is determined based on the presence or absence of low-latency traffic information. In 11be, it is known that an AP that acquires a TXOP can control MAP cooperative transmission as the Sharing AP. However, in control method 2-1, the Sharing AP may change the Sharing AP to another AP based on the low-latency traffic information of the other AP.

[0204] For example, if the number of bits indicating 1 contained in the TID bitmap or the amount of buffer traffic of another AP is greater, the sharing AP may change to another AP.

[0205] An example of this operation is shown in Fig. 28. In Fig. 28, a sharing AP (e.g., AP1) that has acquired a TXOP transmits a MAP Trigger frame to notify its own low-latency traffic information and to request other APs (e.g., shared AP, AP2) to transmit low-latency traffic information (S2801).

[0206] The shared AP (for example, AP2) transmits low latency traffic information in response to the MAP Trigger frame (S2802).

[0207] When a Sharing AP (e.g., AP1) receives low-latency traffic information from a Shared AP and finds that the low-latency traffic information from the Shared AP (e.g., AP2) is greater than its own (e.g., AP1), the Sharing AP (e.g., AP2) may transmit a Multi-User-Request to Send TXOP Sharing (MU-RTS TXS) Trigger frame to the Shared AP (e.g., AP2) (S2803), transfer TXOP control to the Shared AP (e.g., AP2), and change the Shared AP (e.g., AP2) to a Sharing AP. After transmitting the MU-RTS TXS Trigger frame, the own AP (e.g., AP1) operates as a Shared AP.

[0208] In solution method 2-1, low-latency traffic is sent and received between APs, and the AP with the most low-latency traffic is given control of the TXOP, which allows the Sharing AP to schedule transmissions that prioritize low-latency traffic.

[0209] In control method 2-2, a control AP (for example, a sharing AP) determines APs to participate in MAP cooperative transmission based on the presence or absence of low-latency traffic information.

[0210] Specifically, based on the low-latency traffic information of other APs, the Sharing AP determines that APs that do not have low-latency traffic signals (or have few low-latency traffic signals) will participate in MAP cooperative transmission. On the other hand, the Sharing AP determines that APs that have low-latency traffic signals (or have many low-latency traffic signals) will not participate in MAP cooperative transmission. At this time, the Sharing AP allocates different frequency resources for MAP cooperative transmission and non-MAP cooperative transmission. An example of this operation is shown in Figure 29.

[0211] In FIG. 29, the Sharing AP that has acquired the TXOP transmits a MAP Trigger frame to notify its own low-latency traffic information and to request other APs (e.g., Shared AP1 and Shared AP2) to transmit low-latency traffic information (S2901).

[0212] Each Shared AP transmits low latency traffic information in response to the MAP Trigger frame (S2902).

[0213] For example, the TID bitmap included in the low latency traffic information of Sharing AP and Shared AP1 is 00000000, and the TID bitmap included in the low latency traffic information of Shared AP2 is 11110000.

[0214] At this time, based on the TID bitmap of each AP, the Sharing AP decides to participate in MAP cooperative communication because the Sharing AP and Shared AP1 do not have (have few) low-latency traffic signals, but decides not to participate in MAP cooperative communication because Shared AP2 has (has many) low-latency traffic signals.

[0215] Based on the TID bitmap of each AP, the Sharing AP notifies control information (e.g., frequency resource information) regarding MAP cooperative transmission between the Sharing AP and Shared AP1 in a MAP Trigger frame (S2903), and also notifies control information (e.g., frequency resource information) regarding low-latency traffic transmission by Shared AP2 in an MU-RTS TXS Trigger frame (S2904).

[0216] The Sharing AP and each Shared AP notify their subordinate STAs of channel information (e.g., primary channel number and frequency bandwidth) including frequency resource information used for MAP cooperative transmission and transmission of low latency traffic signals (S2905, S2906, S2907).

[0217] The Sharing AP and Shared AP 1 perform MAP cooperative transmission. For example, Shared AP 1 transmits control information for MAP cooperative transmission to the Sharing AP (S2908), and the Sharing AP transmits a MAP Trigger frame including control information for MAP cooperative transmission (e.g., the type of MAP cooperative transmission, transmission timing, and destination STA information) to the Shared AP (S2909).

[0218] The Sharing AP and Shared AP1 transmit MAP coordination signals to their subordinate STAs (for example, STA1 and STA2) based on the control information included in the MAP Trigger frame (S2910).

[0219] Meanwhile, Shared AP2, which transmits low latency traffic signals, continuously transmits low latency traffic (Latency sensitive (LS)) signals to subordinate STAs (for example, STA3) using the allocated frequency resources (S2911, S2913, S2915).

[0220] A STA under Shared AP2 (for example, STA3) transmits an ACK to the LS (S2912, S2914, S2916).

[0221] Solution 2-2 determines which APs participate in MAP cooperative transmission based on the presence or absence of low-latency traffic signals, enabling MAP cooperative control based on each AP's request for transmitting a low-latency traffic signal. For example, an AP that wants to transmit a low-latency traffic signal can continuously transmit the low-latency traffic signal using non-MAP cooperative transmission. Furthermore, an AP that does not transmit a low-latency traffic signal can improve communication quality through MAP cooperative transmission.

[0222] In control method 2-3, the control information of C-SR is changed depending on whether or not a low-latency traffic signal is present. Three examples of the control information of C-SR are shown below.

[0223] In the first example, the C-SR transmission power control method is determined depending on whether or not there is a low-latency traffic signal. Each AP (e.g., AP1 and AP2) participating in the C-SR cooperative control performs transmission power control when the C-SR transmission signal it transmits is a non-low-latency traffic signal (i.e., does not include low-latency traffic). A schematic diagram of C-SR in this case is shown in Figure 30.

[0224] An example of the operation of C-SR in this case is shown in FIG.

[0225] In FIG. 31, the Sharing AP transmits a C-SR Info Request to the Shared AP requesting transmission of transmission power control information (S3101).

[0226] An example of signaling of a C-SR Info Request is shown in Figure 32. The C-SR Info Request may be a type of MAP Trigger frame, and is identified as a C-SR Info Request when MAP Sequence = C-SR Info Request. The C-SR Info Request includes a MAP TID bitmap that notifies the presence or absence of a low-latency traffic signal related to MAP cooperative transmission, and Tx Power (PWR) Info that notifies information necessary for transmit power control. The Tx PWR Info includes, for example, the acceptable receiver interference level (ARIL) of the destination STA, the transmit power gain (Tx PWR Gain) of the AP, and the received signal strength (Received Signal Strength Indicator (RSSI)) of the STA.

[0227] The Shared AP that has received the C-SR Info Request transmits a signal (for example, a beacon signal) including Tx PWR Info to the Sharing AP (S3102).

[0228] The Sharing AP determines the transmission power of each AP in C-SR based on the Tx PWR Info of the Shared AP, and notifies the Shared AP of the determined power in a MAP Trigger frame (S3103).

[0229] The Sharing AP and the Shared AP transmit signals including non-low latency traffic signals using the transmission power information notified in the MAP Trigger frame (S3104).

[0230] When an AP (e.g., AP1) includes a low-latency traffic signal in its C-SR transmission signal, it does not perform transmission power control, but when an AP (e.g., AP2) transmits a non-low-latency traffic signal (i.e., does not include a low-latency traffic signal), it performs power control. A schematic diagram of C-SR in this case is shown in Figure 33.

[0231] FIG. 34 shows an example of the operation of C-SR when AP1 is the Sharing AP and AP2 is the Shared AP in FIG. 33 and the Sharing AP transmits a low-latency traffic signal.

[0232] 34, the Sharing AP transmits low latency traffic signals, and the Shared AP is only permitted to transmit non-low latency traffic signals. In other words, the AP transmitting the low latency traffic signals notifies other APs of transmission power control information, while the AP transmitting the non-low latency traffic signals does not notify other APs of transmission power control information.

[0233] For example, the Sharing AP transmits a MAP TID bitmap containing 1 in one of its bits and a MAP Trigger frame containing Tx PWR Info, thereby notifying the Shared AP of transmission power control information (S3401).

[0234] After transmitting the MAP Trigger frame, the Sharing AP transmits a low latency traffic signal without performing transmission power control (S3402).

[0235] The Shared AP also determines from the MAP Trigger frame received from the Sharing AP that the Sharing AP will transmit a low latency traffic signal. In order to reduce interference to STAs receiving the low latency traffic signal, the Shared AP performs transmission power control based on the transmission power control information and transmits a non-low latency traffic signal (S3403).

[0236] In the example shown above, when a low latency traffic signal is included in the C-SR transmission signal, only the AP transmitting the non-low latency traffic signal performs power control. However, each AP may also perform transmission power control. In this case, transmission power control information is transmitted and received between APs as in the operation example shown in Figure 31. The sharing AP may schedule the transmission power of the AP transmitting the low latency traffic signal to be higher than the transmission power of the AP transmitting the non-low latency traffic signal.

[0237] In the first example of control method 2-3, the C-SR transmission power control method is determined depending on whether or not there is a low-latency traffic signal, thereby reducing interference to the low-latency traffic signal and improving the reception quality of the low-latency traffic signal.

[0238] A second example is to change the transmission timing of non-low latency traffic signals in the case of C-SR that includes the transmission of low latency traffic signals.

[0239] At this time, the AP may notify the transmission timing of the low-latency traffic signal to be transmitted by C-SR. For example, an operation example in which the transmission timing is notified by a time offset is shown in Fig. 35. In Fig. 35, the Sharing AP notifies the time offset using a MAP Trigger frame as shown in Fig. 36.

[0240] For example, when the Sharing AP notifies that it will transmit a low latency traffic signal, the Sharing AP simply transmits a MAP Trigger frame in which any bit in the MAP TID bitmap included in the signaling of FIG. 36 is set to 1 (S3501). Furthermore, when any bit in the MAP TID bitmap is set to 1, a Tx offset may also be included. The Tx offset notifies the length of time from the Short Interframe Space (SIFS) after the transmission of the MAP Trigger frame. The Sharing AP transmits a frame (PPDU) that includes a low latency traffic signal before the Tx offset and a non-low latency traffic signal after the Tx offset (S3502).

[0241] After the time notified by the Tx offset has elapsed, the Shared AP transmits a C-SR signal for which transmission power control has been performed at the same time as the Sharing AP transmits a non-low latency traffic signal (S3503).

[0242] Also, Fig. 37 shows an example of operation when the transmission timing is notified by the number of data units (number of PPDUs) and the number of PPDUs is 2. In Fig. 37, the Sharing AP notifies the number of data units by using, for example, the MAP Trigger frame in Fig. 38 (S3701).

[0243] For example, when a sharing AP notifies that it will transmit a low latency traffic signal, it can transmit a MAP Trigger frame in which any bit in the MAP TID bitmap included in the signaling of Fig. 38 is set to 1. Furthermore, when any bit in the MAP TID bitmap is set to 1, a PPDU offset may be included.

[0244] After transmitting the MAP Trigger frame, the PPDU offset transmits a low latency traffic signal for the number of PPDUs notified by the PPDU offset (S3702, S3704), and after transmitting the number of PPDUs notified by the PPDU offset, transmits a non-low latency traffic signal (S3706).

[0245] After the number of PPDUs notified by the PPDU offset has elapsed, the Shared AP transmits a C-SR signal that has undergone transmission power control at the same time that the Sharing AP transmits a non-low latency traffic signal (S3707).

[0246] Upon receiving the PPDU and C-SR signal, each STA transmits an ACK (S3703, S3705, S3708).

[0247] In the second example, by notifying the transmission timing and preventing multiple APs from transmitting at the transmission timing of the low-latency traffic signal, interference with the low-latency traffic signal can be suppressed and the reception quality of the low-latency traffic signal can be improved.

[0248] In the third example, a Parameterized Spatial Reuse (PSR) table (value of transmission power control information (PSR) for Value) is changed depending on the presence or absence of a low-delay traffic signal.

[0249] A schematic diagram of PSR-based SR in 11ax is shown in Figure 39. In Figure 39, STA2 transmits PSR-based SR to AP2 in order to reduce interference to AP1. At this time, the transmission power (TX PWR STA2 ) is calculated using equation (1). The SRP used in equation (1) is calculated using equation (2). ・TX PWR STA2 < SRP - RSSI AP1-STA2 (1) ・SRP = TX PWR AP1 + ARIL AP1 (2)

[0250] On the other hand, a schematic diagram of DL C-SR in 11be is shown in Fig. 40. In Fig. 40, AP2 transmits C-SR to STA2 in order to reduce interference to STA1. At this time, the transmission power TX PWR of AP2 is AP2 can be calculated using equation (3). SRP can be calculated using equation (4). ・TX PWR AP2 < SRP - RSSI AP2-STA1 (3) SRP = TX PWR AP1 + ARIL STA1 (4)

[0251] Generally, the reception performance of STA is considered to be lower than that of AP. STA1 ARIL AP1 It can be expected that the TX PWR will be smaller than AP1 If we assume that is constant, the PSR value in DL C-SR is expected to be smaller than that in PSR-based SR by the difference in the ARIL between the AP and the STA. Furthermore, in C-SR, which transmits low-latency traffic signals, it is necessary to sufficiently suppress interference to the low-latency traffic signals.

[0252] Therefore, when a low latency traffic signal is transmitted in DL C-SR, the value of PSR is interpreted differently. For example, DL C-SR transmission is notified by the signaling shown in FIG. 41. If any bit in the MAP TID bitmap included in FIG. 41 is 1, the value of PSR for Value is interpreted as the value on the right side of Table 3. Furthermore, the value of PSR may be notified in the common information of the Trigger frame or in the user information.

[0253]

[0254] In the third example, by referencing a PSR table suitable for DL ​​low latency traffic signals, the C-SR transmission signal power can be reduced, thereby reducing interference to DL low latency traffic signals.

[0255] [Modification] In any of the embodiments, low-latency traffic information may be notified for each link. For example, an AP Multi-link device (MLD) notifies another AP MLD of low-latency traffic information related to MAP cooperative transmission for each link. Signaling examples for notifying low-latency traffic information related to MAP cooperative transmission for each link are shown in Figures 42, 43, and 44.

[0256] The signaling in Fig. 42 shows an example of notifying a TID bitmap for each link (for example, 2.4 GHz band, 5 GHz band, and 6 GHz band). MAP TID bitmaps are included for the number of links, and each TID bitmap bit corresponds to a TID.

[0257] The signaling in Figure 43 shows an example of notifying a bitmap of links for each TID. The bits in MAP TID n Link bitmap (n corresponds to the TID) correspond to each link.

[0258] The signaling in Figure 44 shows an example in which a link bitmap for each TID is notified using control information. The Direction indicates the communication direction of each Link bitmap (e.g., uplink, downlink, or uplink and downlink). The Link mapping presence indicator indicates whether a bitmap corresponding to each TID is included. For example, if the Link mapping presence indicator bit = 1, the corresponding MAP TID n Link bitmap is included. By using the signaling in Figures 42, 43, and 44, it is possible to determine the TIDs that can be used in MAP coordinated transmission for each link.

[0259] The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the level of integration, the LSI may also be called an IC, system LSI, super LSI, ultra LSI, or system-on-chip (SoC).

[0260] The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

[0261] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology may be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0262] The present disclosure may be implemented in any type of apparatus, device, or system (collectively referred to as a communications apparatus) that has a communications function. The communications apparatus may include a radio transceiver and processing / control circuitry. The radio transceiver may include a receiver and a transmitter, or both functions. The radio transceiver (transmitter and receiver) may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0263] The communication devices are not limited to portable or mobile devices, but also include any kind of non-portable or fixed equipment, devices, and systems, such as smart home devices (such as home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0264] Communications include data communications via cellular systems, wireless LAN systems, communication satellite systems, and the like, as well as data communications via combinations of these.

[0265] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0266] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0267] A communication device according to one embodiment of the present disclosure includes a control unit that generates low-latency traffic information related to multi-access point (AP) coordinated transmission, and a wireless transmission unit that transmits the generated low-latency traffic information.

[0268] In a communication device according to one embodiment of the present disclosure, the low-latency traffic information includes information on traffic signals with priority, information on traffic signals with large buffer queue sizes, information on traffic signals with small tolerable delay amounts, and information on traffic signals with high required quality.

[0269] A communication device according to an embodiment of the present disclosure is an AP, and transmits the low latency traffic information using Restricted-Target Wake Time (R-TWT) control information.

[0270] A communication device according to an embodiment of the present disclosure is an AP, and transmits the low latency traffic information in non-R-TWT control information.

[0271] The non-R-TWT control information of a communication device according to an embodiment of the present disclosure is notified using a Triffic Identifier (TID).

[0272] The TID of the communication device according to one embodiment of the present disclosure is included in a management signal.

[0273] The TID of the communication device according to one embodiment of the present disclosure is notified in a trigger frame.

[0274] The trigger frame of the communication device according to one embodiment of the present disclosure is a trigger frame for Multi-AP management.

[0275] The non-R-TWT control information of a communication device according to an embodiment of the present disclosure is buffer information.

[0276] The low latency traffic information of a communication device according to an embodiment of the present disclosure is notified by a combination of a TID bitmap and buffer information.

[0277] The non-R-TWT control information of a communication device according to an embodiment of the present disclosure is Quality of Service (QoS) information.

[0278] A communication device according to one embodiment of the present disclosure further includes a radio receiving unit that receives low-latency traffic information from other communication devices, and the control unit determines traffic information that can be used for multi-AP cooperative transmission based on the low-latency traffic information from the other communication devices.

[0279] The control unit of a communication device according to one embodiment of the present disclosure determines traffic information that can be used for multi-AP cooperative transmission based on low-latency traffic information from the other communication devices when the communication device is a control AP.

[0280] The communication device according to an embodiment of the present disclosure is an AP, and the control unit determines low latency traffic information to be notified to the other AP based on low latency traffic information of the terminal.

[0281] The low latency traffic information notified to the other APs by the communication device according to an embodiment of the present disclosure is a Buffer Status Report (BSR) for each Basic Service Set (BSS).

[0282] A communication device according to one embodiment of the present disclosure further has a radio receiving unit that receives low-latency traffic information from other communication devices, and the control unit controls multi-AP cooperative transmission based on the low-latency traffic information from the other communication devices.

[0283] The control of the multi-AP coordinated transmission of the communication device according to one embodiment of the present disclosure is the determination of a controlling AP.

[0284] The control of the multi-AP coordinated transmission by the communication device according to one embodiment of the present disclosure is the determination of APs that will participate in the multi-AP coordinated transmission.

[0285] A communication device according to one embodiment of the present disclosure further includes a wireless receiving unit that receives low-latency traffic information from other communication devices, and the control unit changes a control method for Coordinated Spatial Reuse (C-SR) of Multi-AP cooperative transmission based on the low-latency traffic information from the other communication devices.

[0286] The control of the C-SR of the communication device according to one embodiment of the present disclosure is a determination of whether to control transmission power depending on whether there is low latency traffic.

[0287] The control of the C-SR by a communication device according to an embodiment of the present disclosure is to determine the transmission timing depending on whether or not there is low latency traffic.

[0288] The control of the C-SR by a communication device according to an embodiment of the present disclosure is to change transmission power control information depending on whether or not there is low latency traffic.

[0289] The low-latency traffic information of the communication device according to an embodiment of the present disclosure is low-latency traffic information for each link.

[0290] The low latency traffic information for each link of a communication device according to an embodiment of the present disclosure is a TID bitmap for each link.

[0291] The low latency traffic information for each link of a communication device according to an embodiment of the present disclosure is a link bitmap for each TDI.

[0292] The low latency traffic information for each link of a communication device according to an embodiment of the present disclosure includes control information indicating whether or not a link bitmap is present for each TID.

[0293] In a communication method according to an embodiment of the present disclosure, a communication device generates low-latency traffic information related to cooperative transmission and transmits the generated low-latency traffic information.

[0294] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2022-131168, filed on August 19, 2022, are incorporated herein by reference in their entirety.

[0295] One embodiment of the present disclosure is useful in wireless communication systems.

[0296] 401, 501, 1001, 1101 Receiving antenna 402, 502, 1002, 1102 Radio receiving unit 403, 503, 1003, 1103 Preamble demodulation unit 404, 504, 1004, 1104 Data demodulation unit 405, 505, 1005, 1105 Data decoding unit 406 R-TWT control unit 407, 1007 Multi-AP cooperation control unit 408, 1008 Scheduling unit 409, 1009 Data generation unit 410, 1010 Data encoding unit 411, 1011 Data modulation unit 412, 1012 Preamble generation unit 413, 508, 1013, 1108 Radio transmitting unit 414, 509, 1014, 1109 Transmitting antenna 506 Power saving mode control unit 507, 1107 Transmission signal generation unit 1006, 1106 Low latency traffic control unit

Claims

1. A communication device which is an access point, A control unit that generates traffic information related to coordinated transmission, A wireless transmission unit that transmits the generated traffic information, A communication device equipped with the following.

2. The traffic information is Quality of Service (QoS) information of the traffic relating to the cooperative transmission. The communication device according to claim 1.

3. The QoS information includes user priority, The wireless transmission unit transmits the QoS information, including the user priority, to other access points. The communication device according to claim 2.

4. The wireless transmission unit transmits the QoS information of traffic to be added to the cooperative transmission to other access points. The communication device according to claim 2.

5. The wireless transmission unit notifies other access points of the deletion of the traffic related to the cooperative transmission corresponding to the QoS information. The communication device according to claim 2.

6. The traffic information is low-latency traffic information relating to the coordinated transmission. The communication device according to claim 1.

7. The low-latency traffic information includes at least one of the following: information on traffic signals with priority, information on traffic signals with a large buffer queue size, information on traffic signals with a small allowable delay, and information on traffic signals with high required quality. The communication device according to claim 6.

8. The aforementioned communication device is an access point, The wireless transmission unit transmits the low-latency traffic information using Restricted-Target Wake Time (RT WT) control information. The communication device according to claim 6.

9. The aforementioned communication device is an access point, The wireless transmission unit transmits the low-latency traffic information as non-R-TWT control information. The communication device according to claim 6.

10. The aforementioned non-R-TWT control information is communicated using a TrafficIdentifier (TID). The communication device according to claim 9.

11. The aforementioned TID is included in the management signal. The communication device according to claim 10.

12. The aforementioned TID is notified in the trigger frame. The communication device according to claim 10.

13. The trigger frame is the negotiation signal for the coordinated transmission. The communication device according to claim 12.

14. The trigger frame is a transmission start notification signal for the coordinated transmission. The communication device according to claim 12.

15. The aforementioned non-R-TWT control information is buffer information. The communication device according to claim 9.

16. The aforementioned low-latency traffic information is communicated through a combination of the TID bitmap and buffer information. The communication device according to claim 15.

17. The aforementioned non-R-TWT control information is Quality of Service (QoS) information. The communication device according to claim 9.

18. It further includes a wireless receiving unit that receives low-latency traffic information from other communication devices. The control unit determines the traffic information available for the cooperative transmission based on the low-latency traffic information from the other communication device. The communication device according to claim 6.

19. The control unit, when the communication device is a control access point, determines the traffic information available for the cooperative transmission based on the low-latency traffic information from the other communication device. The communication device according to claim 18.

20. The aforementioned communication device is an access point, The control unit determines low-latency traffic information to be notified to the other access point based on the terminal's low-latency traffic information. The communication device according to claim 18.

21. The low-latency traffic information notified to the other access points is a Buffer Status Report (BSR) per Basic Service Set (BSS). The communication device according to claim 20.

22. It further includes a wireless receiving unit that receives low-latency traffic information from other communication devices. The control unit controls the coordinated transmission based on low-latency traffic information from the other communication device. The communication device according to claim 6.

23. The aforementioned low-latency traffic information is low-latency traffic information for each link. The communication device according to claim 6.

24. The low-latency traffic information for each link is a TID bitmap for each link. The communication device according to claim 23.

25. The low-latency traffic information for each link is a Link bitmap for each TID. The communication device according to claim 23.

26. The communication device which is an access point is Generate traffic information related to coordinated transmission, The generated traffic information is transmitted. Communication method.