Wireless communication apparatus, control method, and storage medium

Abstract

To provide a mechanism capable of appropriately applying beamforming to trigger-based uplink multiuser communication.SOLUTION: A notification unit configured to include capability information related to reception of a beam-formed Tributary Power Distribution (TPD) Physical Layer (PHY) ProtocolDataUnit (PDU) transmitted from a plurality of wireless communication apparatuses having a function of a station (STA) in a management frame defined in an Institute of Electrical and Electronics Engineers (IEEE) 802.11 series standard and transmit the management frame to the plurality of wireless communication apparatuses; And transmission means for transmitting the second frame to the plurality of wireless communication devices on the basis of the reception information of the first frame.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a wireless communication device, a control method, and a program. [Background technology]

[0002] With the recent increase in data traffic, development of communication technologies such as wireless local area networks (WLANs) is progressing. The IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard series is known as the main WLAN communication standard. The IEEE 802.11 standard series includes IEEE 802.11a / b / g / n / ac / ax / be. To further improve communication reliability, the IEEE 802.11bn standard is being developed as the successor to the IEEE 802.11be standard. In the IEEE 802.11 Working Group (WG), which is formulating the IEEE 802.11bn standard, the UHR SG will define the standard's goals and scope, while the TGbn will specify the detailed technical content to be included in the standard.

[0003] UHR SG is an abbreviation for Ultra High Reliability Study Group. TGbn is an abbreviation for Task Group bn. The name UHR was established for convenience based on the goals to be achieved by the successor standard and the key features of the standard, and may be renamed once the standard is fully established. Similarly, the name IEEE802.11bn may be renamed once the standard is fully established. However, this specification and the appended claims are essentially applicable to all successor standards to the 802.11be standard.

[0004] The IEEE 802.11 series of standards specifies a procedure for performing uplink multi-user communication in which multiple STAs simultaneously transmit PPDUs (Physical layer (PHY) Protocol Data Units) to an AP. Patent Document 1 describes a procedure for performing uplink multi-user communication, in which the AP transmits a frame called a trigger frame to each STA for simultaneous transmission. Then, the STA that receives the trigger frame performs uplink transmission of the PPDU using transmission parameters based on information contained in the frame a certain time after receiving the frame. Uplink multi-user communication can be achieved through this procedure. These mechanisms for uplink multi-user communication have contributed to efficient bandwidth utilization. The PPDU transmitted from a STA in simultaneous uplink transmission by multiple STAs is called a TB (Trigger-Based) PPDU.

[0005] The IEEE802.11 series of standards also includes a technology called beamforming. In beamforming, a signal transmitting terminal with multiple transmitting antennas transmits radio waves that have a stronger signal strength at the target terminal by appropriately adjusting the strength and phase of the radio waves transmitted from each antenna. To perform beamforming, it is necessary to estimate the channel state along the transmission path from the sender to the receiver in advance, and adjust each antenna based on the estimated results. When beamforming is performed, the results obtained from the channel state estimation are reflected in the strength and phase of the radio waves transmitted from each antenna. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2024-40254 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when a TB PPDU is transmitted from a STA in simultaneous uplink transmission by a plurality of STAs, no consideration has been given to a mechanism for transmitting the TB PPDU by beamforming.

[0008] An object of one aspect of the present invention is to provide a procedural mechanism for applying beamforming to trigger-based uplink multi-user communications.

[0009] The present invention has been made in consideration of at least one of the above-described problems, and an object of one aspect of the present invention is to provide a mechanism for appropriately applying beamforming to trigger-based uplink multi-user communication. [Means for solving the problem]

[0010] A wireless communication device according to one aspect of the present invention is a wireless communication device having an access point function, a notification means for including capability information relating to reception of beamformed TB (Trigger-Based) PPDUs (Physical layer (PHY) Protocol Data Units) transmitted from a plurality of wireless communication devices having STA functions in a management frame defined in the IEEE 802.11 series standard and transmitting the frame to the plurality of wireless communication devices; a first receiving means for receiving a first frame transmitted from the plurality of wireless communication devices based on the capability information; The wireless communication device further comprises a transmitting means for transmitting a second frame to the plurality of wireless communication devices based on reception information of the first frame. [Effects of the Invention]

[0011] According to one aspect of the present invention, it is possible to provide a mechanism that can appropriately apply beamforming to trigger-based uplink multi-user communication. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a wireless communication system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing an example of the functional configuration of a communication device according to the present embodiment. [Figure 3] FIG. 2 is a diagram showing the hardware configuration of a communication device according to the embodiment. [Figure 4] FIG. 3 is a sequence diagram showing communication processing executed in the first embodiment. [Figure 4A] FIG. 10 is a diagram showing another example of the order in which NDP frames are transmitted. [Figure 5] FIG. 2 is a diagram showing an example of a frame format of an element including capability information related to beamforming in the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the claimed invention. Although the embodiments describe multiple features, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined in any desired manner.

[0014] (Network configuration) Fig. 1 shows an example of the configuration of a network according to this embodiment. Fig. 1 shows a configuration including one AP 102 and three STAs 103, 104, and 105 as communication devices that perform wireless LAN communication in accordance with the IEEE802.11bn standard. As shown in Fig. 1, a network 101 formed by the AP 102 is indicated by a circle. The STAs 103, 104, and 105 can transmit and receive signals transmitted and received by the AP 102.

[0015] Note that this diagram is merely an example, and other communication devices performing wireless LAN communication may exist in a wider area. These communication devices may be communication devices performing wireless LAN communication in accordance with the IEEE 802.11be standard. Alternatively, they may be so-called legacy devices that do not comply with the IEEE 802.11bn standard but only comply with the IEEE 802.11a / b / g / n / ac / ax / be standards.

[0016] The AP 102 and the STAs 103, 104, and 105 can also be configured to support wireless communication based on other communication standards, such as Bluetooth®, NFC, and Bluetooth® Low Energy (LE). NFC stands for Near Field Communication. The AP 102 and the STAs 103, 104, and 105 can also be configured to support wired communication using an Ethernet cable or wired communication using optical fiber. The AP 102 and the STAs 103, 104, and 105 can also be configured to support cellular wireless communication, such as 5G and LTE (Long Term Evolution). Specific examples of the AP 102 include, but are not limited to, a wireless LAN router and a personal computer (PC). The AP 102 and the STAs 103, 104, and 105 may also be information processing devices, such as wireless chips that support the transmission and reception of PPDUs. In this case, various controls can be performed by hardware circuits within the wireless chip. Various processes can also be performed by collaboration between a processor, memory, and hardware circuits, such as an ASIP, within the wireless chip. ASIP stands for Application-specific instruction set processor.

[0017] Specific examples of the STAs 103, 104, and 105 include cameras, tablets, smartphones, PCs, mobile phones, video cameras, smart glasses, and wearable devices such as HMDs (head-mounted displays).

[0018] In the following description, the AP 102 and the STAs 103, 104, and 105 will be used as examples.

[0019] (AP and STA configuration) FIG. 2 is a block diagram showing the functional configuration of the AP 102 and the STAs 103, 104, and 105.

[0020] In the example shown in FIG. 2, the AP 102 and the STAs 103, 104, and 105 each include a wireless LAN control unit 201, a wireless frame generation unit 202, a wireless frame processing unit 203, a UI control unit 204, and a storage control unit 205.

[0021] The wireless LAN control unit 201 includes an antenna and circuit for transmitting and receiving wireless signals to and from other communication devices, and a program for controlling them. The wireless LAN control unit 201 controls wireless LAN communications based on frames generated by the frame generation unit in accordance with the IEEE 802.11 standard series.

[0022] The wireless frame generation unit 202 generates frames to be transmitted by the wireless LAN control unit 201 .

[0023] The wireless frame processing unit 203 performs various processes on frames received from other communication devices.

[0024] The UI control unit 204 includes hardware related to the user interface, such as a touch panel or buttons, for accepting operations on the AP by a user who uses the AP, and programs for controlling these. The UI control unit 204 also has a function for presenting information to the user, such as displaying images or outputting audio. The memory control unit 205 controls writing and reading of data to and from memory units, such as ROM and RAM, that store programs and data running on the AP.

[0025] 3 shows the hardware configuration of the AP 102 and STAs 103, 104, and 105 according to this embodiment. The AP and STAs each include, as an example of their hardware configuration, a storage unit 301, a control unit 302, a function unit 303, an input unit 304, an output unit 305, a communication unit 306, and a wireless antenna 307.

[0026] The storage unit 301 is configured with one or more memories such as ROM and / or RAM, and stores various information such as programs for performing various operations described below and communication parameters for wireless communication. Note that, in addition to memories such as ROM and RAM, storage media such as a flexible disk, a hard disk, an SSD (Solid State Drive), an optical disk, and a magneto-optical disk may be used as the storage unit 301. Storage media such as a CD-ROM, a CD-R, a magnetic tape, a non-volatile memory card, and a DVD may also be used.

[0027] The control unit 302 is configured by, for example, one or more processors such as a CPU or MPU, an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), etc. Here, CPU is an acronym for Central Processing Unit, and MPU is an acronym for Micro Processing Unit. The control unit 302 controls the entire device by executing programs stored in the storage unit 301.

[0028] The control unit 302 may control the device in cooperation with an OS (Operating System) and a program stored in the storage unit 301. The control unit 302 also controls the function unit 303 to perform predetermined processes such as imaging, printing, and projection.

[0029] The functional unit 303 is hardware that enables the AP or STA to execute predetermined processing. For example, if the AP or STA is a camera, the functional unit 303 is an imaging unit that performs imaging processing. Also, for example, if the AP or STA is a printer, the functional unit 303 is a printing unit that performs printing processing. Also, for example, if the AP or STA is a projector, the functional unit 303 is a projection unit that performs projection processing. The data processed by the functional unit 303 may be data stored in the storage unit 301, or may be data communicated with another communication device via the communication unit 306, which will be described later.

[0030] The input unit 304 receives various operations from the user. The output unit 305 outputs various types of information to the user. Here, the output by the output unit 305 includes at least one of display on a screen, audio output by a speaker, vibration output, and the like. Note that both the input unit 304 and the output unit 305 may be implemented by a single module, such as a touch panel. Furthermore, the input unit 304 and the output unit 305 may be integrated with the AP or STA, respectively, or may be separate units.

[0031] The communication unit 306 includes a so-called wireless LAN chip and controls wireless communication compliant with the IEEE 802.11 standard series and IP communication. In this embodiment, the communication unit 306 can execute processing compliant with at least the IEEE 802.11bn standard. The communication unit 306 is a processing device that generates UHR PPDUs defined in the IEEE 802.11bn standard, and may also have the function of generating PPDUs of types defined in earlier standards. UHR stands for Ultra High Reliability, and PPDU stands for Physical Layer Protocol Data Unit. The communication unit 306 also controls the wireless antenna 307 to transmit and receive wireless signals for wireless communication. The AP and STA communicate content such as image data, document data, and video data with other communication devices via the communication unit 306.

[0032] The wireless antenna 307 may be physically configured with two or more antennas to achieve MIMO (Multi-Input and Multi-Output) transmission and reception. The wireless antenna 307 may be configured separately from the communication unit 306, or may be configured together with the communication unit 306 as a single module. The wireless antenna 307 is an antenna capable of communication in the 2.4 GHz, 5 GHz, 6 GHz, 45 GHz, and 60 GHz bands. While the communication device in FIG. 3 has one antenna, the communication device may have two or more antennas. Alternatively, the communication device may have a different antenna for each frequency band. While the example in FIG. 3 has only one communication unit 306, a separate communication unit may be provided for each of the multiple wireless antennas. Note that the AP 102 may be any communication device having the configurations in FIGS. 2 and 3, and may be a so-called AP-dedicated communication device such as a wireless LAN router, or a communication device with AP functionality such as a smartphone, camera, or printer.

[0033] (Processing flow) Next, several embodiments will be described, including the flow of the processes executed by the AP and STA as described above, and sequences in a wireless communication system. First Embodiment 4 is a sequence diagram showing an example of processing for UL MU-MIMO communication, which is an example of UL MU communication in which STAs 103, 104, and 105 transmit beamformed PPDUs to AP 102. UL MU communication is an abbreviation for Uplink Multiple User communication. MU-MIMO is an abbreviation for Multiple User - Multiple Input Multiple Output.

[0034] In this embodiment, the AP 102 periodically transmits a beacon frame 401 to the STAs 103, 104, and 105. The beacon frame 401 includes an element called a UHR Capabilities element. The UHR Capabilities element includes capability information related to beamforming in UL MU-MIMO communication described in this embodiment. The STAs 103, 104, and 105 perform UL MU-MIMO communication based on the information in the element.

[0035] FIG. 5 is a diagram showing an example of a frame format of an element including capability information related to beamforming in this embodiment.

[0036] The UHR Capabilities element has the frame format shown in FIG.

[0037] The element type is specified by the Element ID field 501, which indicates 255 in this embodiment. At this time, a Length field 502 and an Element ID Extension field 503 follow. When the Element ID field 501 is 255, the element type cannot be uniquely determined, but by using the Element ID Extension field 503, it is possible to indicate a uniquely determined element type.

[0038] This is followed by a UHR MAC Capabilities Information field 504 and a UHR PHY Capabilities Information field 505 .

[0039] The UHR MAC Capabilities Information field 504 is a field that includes capability information of functions related to the MAC (Medium Access Control) layer that is newly introduced in the IEEE 802.11bn standard.

[0040] The UHR PHY Capabilities Information field 505 is a field that includes capability information of functions related to the PHY (Physical Layer) layer that is newly introduced in the IEEE802.11bn standard.

[0041] In this embodiment, the capability information related to beamforming of the PPDU transmitted by the STA in UL MU communication will be described. The capability information relates to the PHY layer and is therefore included in the UHR PHY Capabilities Information field 505.

[0042] The format of the UHR PHY Capabilities Information field 505 is shown at the bottom of FIG.

[0043] Although FIG. 5 shows only capability information related to beamforming of the PPDU transmitted by the STA in UL MU communication, other information may be included in the UHR PHY Capabilities Information field 505 .

[0044] The UHR PHY Capabilities Information field 505 includes a Support for TB PPDU Beamforming subfield 506, a TB PPDU Beamforming Partial Bandwidth Feedback subfield 507, an Ng=16 Feedback for TB PPDU beamforming subfield 508, a Codebook Size (φ,ψ)={7,5} Feedback for TB PPDU Beamforming subfield 509, and a Sounding Feedback Rate Limit for TB PPDU Beamforming subfield 510.

[0045] The meaning of each subfield is explained below.

[0046] The Support for TB PPDU Beamforming subfield 506 indicates the following: If the element sender is an AP, it indicates whether the AP can receive a beamformed TB PPDU and whether sounding for performing TB PPDU beamforming is possible. If the element sender is a STA, it indicates whether the STA can transmit a beamformed TB PPDU and whether sounding for performing TB PPDU beamforming is possible. The above sounding refers to the process in which the STA sends an NDP (Null Data Packet) frame to the AP, and the AP receives the NDP frame and calculates the channel state.

[0047] In this embodiment, one subfield is used to indicate capability information that is independent of bandwidth, but different subfields may be provided depending on the bandwidth, thereby indicating different capability information for each bandwidth. For example, a Support for TB PPDU Beamforming subfield may be provided for bandwidths of 80 MHz or less, 160 MHz, and 320 MHz. In other words, the UHR PHY Capabilities Information field 505 may include such a Support for TB PPDU Beamforming subfield.

[0048] The TB PPDU Beamforming Partial Bandwidth Feedback subfield 507 indicates whether or not feedback information related to sounding for TB PPDU beamforming can be transmitted and received using a partial bandwidth. Normally, sounding and feedback are performed using the entire channel, but if this subfield is set to 1, sounding feedback can be performed using a resource unit (RU), which is part of the channel. There may be a limit on the size of the RU to be used, for example, a limit of 106 tones or more may be set.

[0049] The Ng=16 Feedback for TB PPDU beamforming subfield 508 indicates the following: That is, it indicates that the terminal can operate as a beamformee with 16 subcarrier groupings in the Compressed Beamforming Report field. A beamformee is a terminal that receives a beamformed PPDU. A terminal that transmits a beamformed PPDU to a beamformer is called a beamformer. When performing beamforming, it may not be necessary to provide feedback for all tones in the RU that is the sounding target. In this case, the amount of information fed back from the beamformee to the beamformer can be reduced by providing feedback for a certain number of tones in groups. The number of groups, which is the number of tones to be grouped, is represented as Ng. In this case, if the Ng=16 Feedback for TB PPDU beamforming subfield 508 is 1, it indicates whether or not the beamformee can transmit information using Ng=16 TB PPDU beamforming as a beamformee. If the sender of this subfield is not a beamformee for TB PPDU beamforming, this is a reserved value.

[0050] The Codebook Size (φ,ψ)={7,5} Feedback for TB PPDU Beamforming subfield 509 indicates the following: Specifically, it indicates whether the Compressed Beamforming Report field transmitted by the beamformee in TB PPDU beamforming sounding supports codebook size (φ,ψ)={7,5}. The beamformee transmits parameters used to adjust the strength and phase of the radio wave signals transmitted by each transmitter of the beamformer for beamforming as sounding feedback information to the beamformer. The above sounding feedback information is generally expressed as a determinant, but in IEEE802.11ac and later, a data format called Compressed Beamforming Report is used to reduce the amount of feedback data transmitted. The determinant representing the sounding feedback information can be expressed using a small amount of angle information, which reduces the amount of data, but the information accuracy varies depending on the number of bits used to represent the angle information. The notified angle is expressed in two ways: φ and ψ. Codebook Size (φ,ψ)={7,5} The Feedback for TB PPDU Beamforming subfield 509 indicates the following: That is, it indicates whether or not sounding feedback information transmission for TB PPDU beamforming can be performed, where the values ​​related to the respective quantization numbers are 7 and 5. If the sender of this subfield is not a beamformee of TB PPDU beamforming, this subfield is a reserved value.

[0051] The Sounding Feedback Rate Limit for TB PPDU Beamforming subfield 510 indicates the following: It indicates information about the upper limit of the transmission data rate of the Compressed Beamforming Report field transmitted by the beamformee in TB PPDU beamforming sounding. For example, if there is no upper limit on the transmission data rate of the Compressed Beamforming Report field, this subfield is 0, and if this subfield is 1, an upper limit exists. The upper limit can be set to, for example, 1500 megabits per second, but is not limited to this.

[0052] In this embodiment, an example has been described in which an AP notifies its capability information by transmitting a beacon frame, but this is not limiting. That is, notification can also be achieved by including a similar element in another frame, in which case the STA can also notify its capability information. In this embodiment, the other frame is assumed to be a management frame such as a probe request frame, a probe response frame, an association request frame, or an association response frame. In this case, the capability information notified by the STA may include information indicating whether or not the STA has the capability to transmit beamformed TB PPDUs. The capability information may also include information indicating whether or not the STA has the capability to receive the above-mentioned sounding feedback information transmitted from the AP. The STA may also notify information indicating whether or not the STA has the capability to transmit beamformed TB PPDUs using another management frame. The AP may also notify information indicating whether or not the STA has the capability to receive beamformed TB PPDUs using another management frame.

[0053] The STAs 103, 104, and 105 individually transmit NDP (Null Data Packet) frames 402 to the AP 102. For example, when the STAs 103, 104, and 105 receive a beacon frame 401 including the above-described capability information, they transmit the NDP frames 402 based on the capability information in the beacon frame 401. Note that at this time, the STAs 103, 104, and 105 may transmit the NDP frames 402 only if the capability information indicates that the AP 102 can receive the beamformed TB PPDU.

[0054] The order in which the NDP frames 402 are transmitted may be other than that shown in Fig. 4. For example, as shown in Fig. 4A, the AP 102 may transmit a frame 401A to the STAs 103, 104, and 105 prompting them to transmit an NDP frame, and the STAs 103, 104, and 105 may then transmit the NDP frame 402 to the AP after receiving the frame. The STAs 103, 104, and 105 may also transmit an NDPA (NDP announcement) frame (not shown in Fig. 4) to the AP 102 before transmitting the NDP frame 402 to the AP 102. The NDPA frame contains request information regarding sounding, and is transmitted to the destination terminal of the NDP frame, i.e., the terminal transmitting the feedback, before transmitting the NDP frame. Examples of information contained in the NDPA frame include the sounding bandwidth, the number of subcarrier groupings Ng, and a codebook size parameter.

[0055] A terminal that receives an NDP frame generates feedback information based on the information contained in the NDP frame and feeds it back to the terminal that transmitted the NDP frame. At this time, the feedback configuration information must not contradict the capability information contained in the UHR PHY Capabilities Information field 505 in the beacon frame 401 received from the AP 102. For example, if the Ng=16 Feedback for TB PPDU beamforming subfield 508 is 0, Ng=16 should not be set, but if the same subfield is 1, Ng=16 may be set.

[0056] The AP 102 calculates data constituting a Compressed Beamforming Report frame 403 from the received signal of the NDP frame 402, and transmits the data to the STAs 103, 104, and 105. The Compressed Beamforming Report frame 403 includes the number of groupings and the codebook size.

[0057] The STAs 103, 104, and 105 apply the values ​​calculated from the channel state estimation included in the received Compressed Beamforming Report frame 403 to the strength and phase of the radio signal transmitted by each transmitter, thereby enabling them to transmit beamformed PPDUs to the AP 102 in subsequent UL MU-MIMO communication.

[0058] Next, the AP 102 transmits a trigger frame 404 for UL MU-MIMO communication to the STAs 103, 104, and 105. The trigger frame includes RU information used by each STA in UL MU-MIMO communication and can notify each STA of the start timing of the communication to be used. The STAs 103, 104, and 105 transmit a TB PPDU 405 to the AP 102 a certain time after receiving the trigger frame 404. For example, a short interframe space (SIFS) can be used for this certain period. At this time, the TB PPDU 405 is beamformed by applying the information included in the Compressed Beamforming Report frame 403 to the transmitter of each STA, as described above. The AP 102 transmits a Multi-STA Block Ack frame 406 to the STAs 103, 104, and 105 to notify the STAs that transmitted the TB PPDU 405 of the reception result of the TB PPDU 405.

[0059] The trigger frame 404 may be configured to include an indication bit indicating whether beamforming should be used to transmit the TB PPDU. This indication bit can be configured to be included in the UHR variant Common Info field. Furthermore, a value indicating UHR is stored in the PHY Version Identifier subfield, which constitutes B12 to B14 of the Special User Info field format of the trigger frame 404. This means that a UHR TB PPDU, which is a TB PPDU in UHR format, is being requested as the TB PPDU that responds to the trigger frame. The value indicating UHR is, for example, 0b001 (0x001). Each STA that receives a trigger frame including an indication bit indicating that beamforming should be performed transmits a TB PPDU 405 that uses beamforming technology to impart directionality to the data to be transmitted to the AP 102. It is also possible to configure the trigger frame 404 to indicate whether beamforming should be performed for each STA. In this case, the indication can be made in the User Info field of the UHR variant User Info field format of the trigger frame 404. Specifically, the User Info field may be configured to store AID information for identifying the STA, RU information, and an indication bit indicating whether beamforming should be performed. In this case, a STA that receives the trigger frame 404 analyzes the User Info field corresponding to the AID assigned to it and determines whether beamforming should be performed. A STA that is specified in the trigger frame 404 to perform beamforming transmits a TB PPDU 405 addressed to the AP 102, with directionality toward the AP 102 using beamforming technology. On the other hand, a STA that is not specified in the trigger frame 404 to perform beamforming may transmit a TB PPDU 405 with omni-directivity.

[0060] As described above, this embodiment assumes that the format of the TB PPDU 405 transmitted using beamforming technology is the UHR TB PPDU. The UHR TB PPDU is a PPDU consisting of a preamble and a data field. The preamble includes a Short Training Field (STF), a Long Training Field (LTF), a Signal Field (SIG), and a data field. At the beginning of the PPDU, L (Legacy)-STF, L-LTF, and L-SIG are placed to ensure backward compatibility with the IEEE 802.11a / b / g / n standards. The L-LTF is placed immediately after the L-STF, and the L-SIG is placed immediately after the L-LTF. Furthermore, a Repeated L-SIG (RL-SIG) is placed immediately after the L-SIG. The contents of the L-SIG are repeatedly transmitted in the RL-SIG field. The RL-SIG allows the receiver to recognize that the PPDU complies with IEEE 802.11ax or later standards. The L-STF is used for PHY frame signal detection, automatic gain control (AGC), and timing detection. The L-LTF is used for frequency and time synchronization. The L-SIG is used to transmit control information, including data transmission rate and PHY frame length. The PPDU also includes a Universal Signal Field (U-SIG) immediately after the RL-SIG. The U-SIG is a field commonly used in IEEE 802.11be and later standards, transmitting control information for each standard. The PHY Version Identifier, the first three bits of the U-SIG in the UHR TB PPDU, contains 0b001 (0x001), indicating UHR. The U-SIG is followed by the UHR-STF, an STF for UHR, and the UHR-LTF, an LTF for UHR. UHR-LTF is information used for MIMO estimation, beamforming estimation, etc. Multiple UHR-LTFs can be placed depending on the number of MIMO antennas and whether beamforming is required. A maximum of four UHR-LTFs can be placed. A data field is placed after the UHR-LTF.The STA that has been indicated to perform beamforming uses beamforming technology to control data transmission so that the data in the data field has directionality toward the AP 102. At this time, beamforming of the data field signal is realized by applying the information included in the Compressed Beamforming Report frame 403 to the transmitter of each STA.

[0061] While the example of UL MU-MIMO communication has been described here, it is also possible to transmit and receive capability information related to TB PPDU beamforming in UL MU OFDMA communication. UL MU OFDMA communication uses spatial multiplexing to enable simultaneous transmission and reception between multiple terminals in the same frequency band. In UL MU OFDMA communication, the channel is divided into resource units (RUs) consisting of multiple consecutive subcarriers, and multiple STAs transmit UL MUs using different RUs. In order for the AP to notify each STA of the RU information it will use, the AP transmits a trigger frame containing RU allocation information to the STA that is transmitting over the UL. After receiving the trigger frame, the STA transmits a TB PPDU to the AP a certain amount of time after receiving the trigger frame, based on the RU allocation information in the trigger frame.

[0062] Sounding for UL MU OFDMA communication can be achieved in the same way as sounding for UL MU-MIMO communication described above. Before performing UL MU-MIMO communication, the STA receives a Compressed Beamforming Report via sounding. Beamforming can be performed on the TB PPDU by applying values ​​calculated from the channel state estimation included in the received Compressed Beamforming Report frame to the strength and phase of the radio signal transmitted by each transmitter.

[0063] As described above, according to this embodiment, when a STA transmits a PPDU in simultaneous uplink transmission of multiple STAs, the PPDU can be transmitted using beamforming. The STAs and AP can transmit, receive, and share capability information related to beamforming of the TB PPDU used in simultaneous uplink transmission of multiple STAs. The capability information includes not only information on whether beamforming of the TB PPDU can be performed, but also information on whether a specific bandwidth to be used and sounding-related parameters can be used.

[0064] In this embodiment, elements with names beginning with UHR, which refers to the IEEE802.11bn standard, have been described, but the names may be different. Furthermore, the capability information exemplified in the various subfields 506 to 510 is merely an example, and it is possible to notify only part of the capability information, or to configure the device to notify only at least one piece of capability information. For example, only the Support for TB PPDU Beamforming subfield 506 may be notified. Furthermore, this other capability information may be transmitted to the other device by communicating another Notification frame.

[0065] It is also possible to provide a system or device with a recording medium on which program code for software that realizes the above-described functions is recorded, and have the computer (CPU, MPU) of the system or device read and execute the program code stored on the recording medium. In this case, the program code itself read from the recording medium realizes the functions of the above-described embodiments, and the recording medium on which the program code is stored constitutes the above-described device.

[0066] Examples of storage media that can be used to supply the program code include flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, ROMs, and DVDs.

[0067] In addition, not only can the above-mentioned functions be realized by the computer executing the program code it has read, but the OS running on the computer can also perform some or all of the actual processing based on the instructions of the program code to realize the above-mentioned functions.

[0068] Furthermore, the program code read from the storage medium may be written to a memory provided on a function expansion board inserted into a computer or a function expansion unit connected to the computer, and a CPU provided on the function expansion board or function expansion unit may then perform some or all of the actual processing based on the instructions of the program code to realize the above-mentioned functions.

[0069] The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0070] The following additional notes are provided regarding the above-described embodiments.

[0071] [Appendix 1] A wireless communication device having an access point function, a notification means for including capability information relating to reception of beamformed TB (Trigger-Based) PPDUs (Physical layer (PHY) Protocol Data Units) transmitted from a plurality of wireless communication devices having STA functions in a management frame defined in the IEEE 802.11 series standard and transmitting the frame to the plurality of wireless communication devices; a first receiving means for receiving a first frame transmitted from the plurality of wireless communication devices based on the capability information; a transmitting means for transmitting a second frame to the plurality of wireless communication devices based on reception information of the first frame.

[0072] [Appendix 2] the first frame is a Null Data Packet (NDP) frame, 2. The wireless communication device according to claim 1, wherein the second frame is a Compressed Beamforming Report frame.

[0073] [Appendix 3] The wireless communication device according to claim 1 or 2, further comprising a second receiving means for receiving, from the plurality of wireless communication devices, a TB PPDU beamformed based on information contained in the second frame.

[0074] [Appendix 4] The wireless communication device described in Supplementary Note 1, characterized in that the capability information includes receiving function information indicating whether or not it is possible to receive beamformed TB PPDUs from the multiple wireless communication devices.

[0075] [Appendix 5] 5. The wireless communication device according to claim 4, wherein the receiving function information includes information relating to a bandwidth of 80 MHz or less, information relating to a bandwidth of 160 MHz, and information relating to a bandwidth of 320 MHz.

[0076] [Appendix 6] The wireless communication device according to any one of Supplementary Notes 1 to 5, characterized in that the capability information includes information indicating whether sounding feedback to the plurality of wireless communication devices is possible.

[0077] [Appendix 7] A wireless communication device described in any one of Supplementary Notes 1 to 6, characterized in that the capability information includes information indicating whether sounding feedback using an RU (Resource Unit) that constitutes part of the channel is possible.

[0078] [Appendix 8] The wireless communication device according to any one of Supplementary Notes 1 to 7, characterized in that the capability information includes information indicating whether the device is compatible with a case in which the number of subcarrier groupings in sounding feedback is 16.

[0079] [Appendix 9] The wireless communication device described in any one of Supplementary Notes 1 to 8, characterized in that the capability information includes information indicating whether or not the device supports a codebook size in sounding feedback of (φ, ψ) = {7, 5}.

[0080] [Appendix 10] 10. The wireless communication device according to any one of Supplementary notes 1 to 9, wherein the capability information includes information indicating whether or not there is an upper limit on the transmission rate in sounding feedback.

[0081] [Appendix 11] A wireless communication device described in any one of Supplementary Notes 1 to 10, further comprising a third receiving means for receiving second capability information related to the transmission of beamformed TB PPDUs to the wireless communication device from the plurality of wireless communication devices.

[0082] [Appendix 12] A wireless communication device having a function of STA conforming to the IEEE 802.11 series of standards, a first transmitting means for transmitting a TB (Trigger-Based) PPDU (Physical layer (PHY) Protocol Data Unit) to a first wireless communication device having a function of an access point simultaneously with another second wireless communication device having a function of an STA in response to a trigger signal from the first wireless communication device; a first receiving means for receiving capability information of the first wireless communication device related to reception of the beamformed TB PPDU from the first wireless communication device via a management frame defined in the IEEE 802.11 series standard; a second transmitting means for transmitting a first frame to the first wireless communication device based on the capability information; a second receiving means for receiving a second frame transmitted from the first wireless communication device based on the first frame; The wireless communication device, wherein the first transmitting means transmits a TB PPDU beamformed based on information included in the second frame to the first wireless communication device.

[0083] [Appendix 13] The wireless communication device described in Appendix 12, characterized in that the first transmitting means transmits a beamformed TB PPDU when the capability information indicates that the first wireless communication device is capable of receiving the beamformed TB PPDU.

[0084] [Appendix 14] A wireless communication device having a function of STA conforming to the IEEE 802.11 series of standards, a notification means for including capability information related to transmission of a beamformed TB (Trigger-Based) PPDU (Physical layer (PHY) Protocol Data Unit) to a first wireless communication device having a function of an access point in a management frame defined in the IEEE 802.11 series standard and transmitting the frame to the first wireless communication device; a first transmitting means for transmitting a first frame to the first wireless communication device based on the capability information; receiving means for receiving a second frame transmitted from the first wireless communication device in response to the first frame; and second transmitting means for transmitting a TB PPDU beamformed based on information included in the second frame to the first wireless communication device.

[0085] [Appendix 15] The wireless communication device described in Appendix 14, characterized in that the capability information includes transmission function information indicating whether or not it is possible to transmit a beamformed TB PPDU to the first wireless communication device, and reception function information indicating whether or not it is possible to receive sounding feedback information transmitted from the first wireless communication device.

[0086] [Appendix 16] A method for controlling a wireless communication device having an access point function, comprising: transmitting capability information relating to reception of beamformed TB (Trigger-Based) PPDUs (Physical layer (PHY) Protocol Data Units) transmitted from a plurality of wireless communication devices having STA functions to the plurality of wireless communication devices in a management frame defined in the IEEE 802.11 series standard; receiving a first frame transmitted from the plurality of wireless communication devices based on the capability information; and transmitting a second frame to the plurality of wireless communication devices based on reception information of the first frame.

[0087] [Appendix 17] A method for controlling a wireless communication device having a function of an STA conforming to the IEEE 802.11 series of standards, receiving, from a first wireless communication device having a function of an access point, capability information of the first wireless communication device relating to reception of a beamformed TB (Trigger-Based) PPDU (Physical layer (PHY) Protocol Data Unit) via a management frame specified in the IEEE 802.11 series standard; transmitting a first frame to the first wireless communication device based on the capability information; receiving a second frame transmitted from the first wireless communication device based on the first frame; a step of transmitting a TB PPDU beamformed based on information contained in the second frame to the first wireless communication device in response to a trigger signal from the first wireless communication device.

[0088] [Appendix 18] A method for controlling a wireless communication device having a function of an STA conforming to the IEEE 802.11 series of standards, a step of including capability information related to transmission of a beamformed TB (Trigger-Based) PPDU (Physical layer (PHY) Protocol Data Unit) to a first wireless communication device having a function of an access point in a management frame defined in the IEEE 802.11 series standard and transmitting the management frame to the first wireless communication device; transmitting a first frame to the first wireless communication device based on the capability information; receiving a second frame transmitted from the first wireless communication device in response to the first frame; transmitting a TB PPDU beamformed based on information included in the second frame to the first wireless communication device.

[0089] [Appendix 19] A program for causing a computer to function as each of the means provided in the wireless communication device described in any one of Supplementary Notes 1 to 15. [Explanation of symbols]

[0090] 101 Network 102 AP 103, 104, 105 STA

Claims

1. A wireless communication device having an access point function, a notification means for including capability information relating to reception of beamformed Trigger-Based (TB) Physical layer (PHY) Protocol Data Units (PPDUs) transmitted from a plurality of wireless communication devices having STA functions in a management frame defined in the IEEE 802.11 series standard and transmitting the frame to the plurality of wireless communication devices; a first receiving means for receiving a first frame transmitted from the plurality of wireless communication devices based on the capability information; a transmitting means for transmitting a second frame to the plurality of wireless communication devices based on reception information of the first frame.

2. the first frame is a Null Data Packet (NDP) frame, 2. The wireless communication device according to claim 1, wherein the second frame is a Compressed Beamforming Report frame.

3. 2. The wireless communication device according to claim 1, further comprising: a second receiving means for receiving, from the plurality of wireless communication devices, a TB PPDU beamformed based on information included in the second frame.

4. The wireless communication device according to claim 1 , wherein the capability information includes reception function information indicating whether or not reception of beamformed TB PPDUs from the plurality of wireless communication devices is possible.

5. 5. The wireless communication device according to claim 4, wherein the reception function information includes information relating to a bandwidth of 80 MHz or less, information relating to a bandwidth of 160 MHz, and information relating to a bandwidth of 320 MHz.

6. The wireless communication device according to claim 1 , wherein the capability information includes information indicating whether sounding feedback to the plurality of wireless communication devices is possible.

7. The wireless communication device according to claim 6, wherein the capability information includes information indicating whether sounding feedback using a resource unit (RU) constituting a part of a channel is possible.

8. 7. The wireless communication device according to claim 6, wherein the capability information includes information indicating whether the device is compatible with a case where the number of subcarrier groupings in sounding feedback is 16.

9. 7. The wireless communication device according to claim 6, wherein the capability information includes information indicating whether or not the device supports a codebook size in sounding feedback of (φ, ψ)={7, 5}.

10. The wireless communication device according to claim 6 , wherein the capability information includes information indicating whether or not there is an upper limit on a transmission rate in sounding feedback.

11. 2. The wireless communication device according to claim 1, further comprising: a third receiving means for receiving, from the plurality of wireless communication devices, second capability information related to transmission of beamformed TB PPDUs to the wireless communication device.

12. A wireless communication device having a function of STA conforming to the IEEE 802.11 series of standards, a first transmitting means for transmitting a TB (Trigger-Based) PPDU (Physical layer (PHY) Protocol Data Unit) to a first wireless communication device having a function of an access point simultaneously with another second wireless communication device having a function of an STA in response to a trigger signal from the first wireless communication device; a first receiving means for receiving capability information of the first wireless communication device related to reception of a beamformed TB PPDU from the first wireless communication device via a management frame defined in the IEEE 802.11 series standard; a second transmitting means for transmitting a first frame to the first wireless communication device based on the capability information; a second receiving means for receiving a second frame transmitted from the first wireless communication device based on the first frame; The wireless communication device, wherein the first transmitting means transmits a TB PPDU beamformed based on information included in the second frame to the first wireless communication device.

13. 13. The wireless communication device according to claim 12, wherein the first transmitting means transmits a beamformed TB PPDU when the capability information indicates that the first wireless communication device is capable of receiving the beamformed TB PPDU.

14. A wireless communication device having a function of STA conforming to the IEEE 802.11 series of standards, a notification means for including capability information related to transmission of a beamformed Trigger-Based (TB) Physical layer (PHY) Protocol Data Unit (PPDU) to a first wireless communication device having an access point function in a management frame defined in the IEEE 802.11 series standard and transmitting the frame to the first wireless communication device; a first transmitting means for transmitting a first frame to the first wireless communication device based on the capability information; receiving means for receiving a second frame transmitted from the first wireless communication device in response to the first frame; and second transmitting means for transmitting a TB PPDU beamformed based on information included in the second frame to the first wireless communication device.

15. 15. The wireless communication device according to claim 14, wherein the capability information includes transmission capability information indicating whether or not a beamformed TB PPDU can be transmitted to the first wireless communication device, and reception capability information indicating whether or not sounding feedback information transmitted from the first wireless communication device can be received.

16. A method for controlling a wireless communication device having an access point function, comprising: transmitting capability information related to reception of beamformed trigger-based (TB) physical layer (PHY) protocol data units (PPDUs) transmitted from a plurality of wireless communication devices having STA functions to the plurality of wireless communication devices in a management frame defined in the IEEE 802.11 series standard; receiving a first frame transmitted from the plurality of wireless communication devices based on the capability information; and transmitting a second frame to the plurality of wireless communication devices based on reception information of the first frame.

17. A method for controlling a wireless communication device having a function of an STA conforming to the IEEE 802.11 series of standards, comprising: receiving, from a first wireless communication device having a function of an access point, capability information of the first wireless communication device relating to reception of a beamformed Trigger-Based (TB) Physical layer (PHY) Protocol Data Unit (PPDU) via a management frame specified in the IEEE 802.11 series standard; transmitting a first frame to the first wireless communication device based on the capability information; receiving a second frame transmitted from the first wireless communication device based on the first frame; and transmitting a TB PPDU beamformed based on information contained in the second frame to the first wireless communication device in response to a trigger signal from the first wireless communication device.

18. A method for controlling a wireless communication device having a function of an STA conforming to the IEEE 802.11 series of standards, comprising: transmitting capability information related to transmission of a beamformed Trigger-Based (TB) Physical layer (PHY) Protocol Data Unit (PPDU) to a first wireless communication device having a function of an access point, the capability information being included in a management frame defined in the IEEE 802.11 series standard, to the first wireless communication device; transmitting a first frame to the first wireless communication device based on the capability information; receiving a second frame transmitted from the first wireless communication device in response to the first frame; transmitting a TB PPDU beamformed based on information included in the second frame to the first wireless communication device.

19. A program for causing a computer to function as each of the means provided in the wireless communication device according to any one of claims 1 to 15.

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