Communication device, control method of communication device, and non-transitory computer-readable storage medium

Abstract

A communication apparatus compliant with IEEE 802.11 family standards includes data transmission means for transmitting data frames to another communication apparatus a plurality of times in succession, each data frame including data units, generation means for generating a Block Acknowledgement Request (BAR) frame, BAR transmission means for transmitting the BAR frame to the other communication apparatus after the plurality of times of transmission of the data frames, and reception means for receiving a Block Acknowledgement (BA) frame from the other communication apparatus as a response to the BAR frame. The generation means indicates a sequence number of data units in an initial data frame among the plurality of times of transmitted data frames using a predetermined field in the BAR frame, and the predetermined field includes a field different from a start sequence number field in the BAR frame.

Description

Technical Field

[0001] This invention relates to communication devices, control methods, and non-transitory computer-readable storage media. Background Technology

[0002] With the recent increase in data communication volume, the development of Wireless Local Area Network (LAN) communication technology has been ongoing. As a major standard for wireless LANs, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 series of standards is known. The IEEE 802.11 series includes standards such as IEEE 802.11a / b / g / n / ac / ax. For example, 802.11ax is a standard (PTL1) that uses Orthogonal Frequency Division Multiple Access (OFDMA) technology to improve communication speed under congestion conditions, while also achieving a peak throughput of up to 9.6 gigabits per second (Gbps).

[0003] Furthermore, starting with 802.11n, a method called Block Ack (BA) was incorporated. This method responds on the sending side with a bitmap showing which frames have been received after multiple frames have been sent as a single transmission. Ack stands for Acknowledgment. BA uses a bitmap indicating which data has been received from the sequence number of the initially received data (data frame) and subsequent consecutive sequence numbers. For each sequence number of the transmitted data, it indicates which data has been received and which has not yet been received. For 802.11n, the sequence number of the initially received data in the BA is 12 bits, and a 128-byte field is prepared for the bitmap. The data receiving side acknowledges the sequence number of the received data, counting from the sequence number of the initially received data. Next, the bit corresponding to the received data is set to 1. All other bits are set to 0. Consider an example where the sequence number of the initially received data is 5, and the sequence numbers of the multiple received data are 5, 6, and 8. The sequence number of the initially received data is 5. Bits 1, 2, and 4 of the bitmap are set to 1. All other bits are set to 0. In this way, the sending side that receives the data in the Block Acknowledgment Request (BA) can confirm what data the receiving side has correctly received. Furthermore, a Block Acknowledgment Request (BAR) is prepared as a frame to confirm when the BA should be sent to the data receiving side. Upon receiving the BAR, the data receiving side acknowledges the sequence number of the received data (data frame) and responds with a BA.

[0004] Using this processing, the data sending side can send data as a single transmission and, as a result, increase the throughput of data transmission because overlap in data transmission is removed.

[0005] A task force has been established to work on the subsequent standard IEEE 802.11be, with the aim of further improving throughput, enhancing frequency utilization, and reducing communication latency. For the IEEE 802.11be standard, a technology for communication is being researched in which a single access point (AP) establishes multiple links with a single site (STA) or terminal device via multiple different frequency channels.

[0006] Citation List

[0007] Patent documents

[0008] [PTL1] Japanese Patent Application Publication No. 2018-50133 Summary of the Invention

[0009] Technical issues

[0010] For the IEEE 802.11be standard, one approach being investigated to further improve throughput involves increasing the number of fields in the bitmap allocated to the BA to allow more data to be transmitted as a single data set. By increasing the amount of data to be transmitted as a single data set, it seems reasonable to avoid sequence number overlap, thereby increasing the maximum value that a sequence number can represent. However, there is a possibility that the sequence number of the initially received data indicated in the BA or BAR may become unrepresentable by the currently prepared fields alone.

[0011] In view of the above problems, this disclosure provides a technique for extending the region of the sequence number indicated by the frame used to control the BA.

[0012] Solution to the problem

[0013] To achieve the above objectives, a communication device according to one aspect of the present invention has the following configuration: a communication device conforming to the IEEE 802.11 series standards, characterized by comprising:

[0014] A data transmission component is used to continuously send data frames to another communication device multiple times, each data frame including a data unit;

[0015] The generation component is used to generate the Block Acknowledgment Request (BAR) frame;

[0016] A BAR transmitting component is configured to transmit the BAR frame to the other communication device after a series of transmissions of the data frames; and

[0017] A receiving component is configured to receive, from the other communication device, a block acknowledgment (BA) frame as a response to the BAR frame, wherein

[0018] The generation component uses a predetermined field in the BAR frame to indicate the sequence number of the data unit in the initial data frame among multiple consecutively transmitted data frames, and

[0019] The predetermined fields include fields that are different from the start sequence number field in the BAR frame.

[0020] One aspect of the present invention provides a communication device that conforms to the IEEE 802.11 series of standards, characterized in that it comprises:

[0021] A data transmission component is used to continuously send data frames to another communication device multiple times, each data frame including a data unit;

[0022] The generation component is used to generate the Block Acknowledgment Request (BAR) frame;

[0023] A BAR transmitting component is configured to transmit the BAR frame to the other communication device after a series of transmissions of the data frames; and

[0024] A receiving component is configured to receive, from the other communication device, a block acknowledgment (BA) frame as a response to the BAR frame, wherein

[0025] The generating component indicates, in the start sequence number field of the start sequence control field in the BAR frame, the sequence number of the data unit in the initial data frame among the data frames transmitted in multiple consecutive transmissions, and

[0026] The length of the starting sequence number field is variable.

[0027] One aspect of the present invention provides a communication device that conforms to the IEEE 802.11 series of standards, characterized in that it comprises:

[0028] A data receiving component is used to continuously receive data frames from another communication device multiple times, each data frame including a data unit;

[0029] A BAR receiving component is configured to receive a Block Acknowledgment Request (BAR) frame from the other communication device after receiving multiple consecutive data frames; and

[0030] A transmitting component is used to send a block acknowledgment (BA) to the other communication device as a response to the BAR frame, wherein

[0031] The sequence number of the data unit in the initial data frame of the data frames transmitted in multiple consecutive transmissions is indicated using a predetermined field in the BAR frame, and

[0032] The predetermined fields include fields that are different from the start sequence number field in the BAR frame.

[0033] One aspect of the present invention provides a communication device that conforms to the IEEE 802.11 series of standards, characterized in that it comprises:

[0034] A data receiving component is used to continuously receive data frames from another communication device multiple times, each data frame including a data unit;

[0035] A BAR receiving component is configured to receive a Block Acknowledgment Request (BAR) frame from the other communication device after receiving multiple consecutive data frames; and

[0036] A transmitting component is used to transmit a block acknowledgment (BA) frame to the other communication device as a response to the BAR frame, wherein

[0037] The sequence number of the data unit in the initial data frame of the multiple consecutively transmitted data frames is indicated in the start sequence number field of the start sequence control field in the BAR frame, and

[0038] The length of the starting sequence number field is variable.

[0039] One aspect of the present invention provides a control method for a communication device conforming to the IEEE 802.11 series standards, characterized in that it comprises:

[0040] Sending data frames to another communication device multiple times in succession, each data frame including a data unit;

[0041] Generate a Block Acknowledgment Request (BAR) frame;

[0042] After a series of transmissions of the data frames, the BAR frame is transmitted to the other communication device; and

[0043] Receive a block acknowledgment (BA) frame as a response to the BAR frame from the other communication device, wherein

[0044] In the generation process, the sequence number of the data unit in the initial data frame of the data frames transmitted in multiple consecutive transmissions is indicated using a predetermined field in the BAR frame, and

[0045] The predetermined fields include fields that are different from the start sequence number field in the BAR frame.

[0046] One aspect of the present invention provides a computer-readable storage medium storing a program for causing a computer to execute a control method for a communication device conforming to the IEEE 802.11 series of standards, characterized in that it comprises:

[0047] Sending data frames to another communication device multiple times in succession, each data frame including a data unit;

[0048] Generate a Block Acknowledgment Request (BAR) frame;

[0049] After a series of transmissions of the data frames, the BAR frame is transmitted to the other communication device; and

[0050] Receive a block acknowledgment (BA) frame as a response to the BAR frame from the other communication device, wherein

[0051] In the generation process, the sequence number of the data unit in the initial data frame of the data frames transmitted in multiple consecutive transmissions is indicated using a predetermined field in the BAR frame, and

[0052] The predetermined fields include fields that are different from the start sequence number field in the BAR frame.

[0053] Beneficial effects of the invention

[0054] According to the present invention, the region of the sequence number indicated by the frame used for control block confirmation (BA) is expanded.

[0055] Other features and advantages of the invention will become clear from the following description taken in conjunction with the accompanying drawings. It should be noted that throughout the drawings, the same reference numerals denote the same or identical components. Attached Figure Description

[0056] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0057] Figure 1 This is a diagram illustrating an example configuration of a wireless communication system.

[0058] Figure 2 This is a diagram illustrating an example of the hardware configuration of a communication device according to an embodiment.

[0059] Figure 3 This is a diagram illustrating an example of the functional configuration of a communication device according to an embodiment.

[0060] Figure 4A This is a flowchart (1) illustrating the process performed by the AP.

[0061] Figure 4B This is a flowchart (2) illustrating the process performed by the AP.

[0062] Figure 5A This is a flowchart (1) illustrating the process performed by the STA.

[0063] Figure 5BThis is a flowchart (2) illustrating the process performed by STA.

[0064] Figure 6 This is a sequence diagram illustrating the data exchange process.

[0065] Figure 7 This is a diagram illustrating an example of an ADDBA request frame.

[0066] Figure 8 This is a diagram illustrating an example of an ADDBA response frame.

[0067] Figure 9 This is an example diagram illustrating a BAR frame.

[0068] Figure 10 This is a diagram illustrating an example of a BA frame.

[0069] Figure 11 This is a table illustrating specific examples of BAR types indicated by BAR or BA. Detailed Implementation

[0070] In the following, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments are not intended to limit the scope of the claimed invention. Several features are described in the embodiments, but the invention is not limited to claiming all such features, and multiple such features may be appropriately combined. Furthermore, in the drawings, the same reference numerals are given the same or similar configuration, and redundant descriptions thereof are omitted.

[0071] Configuration of wireless communication system

[0072] Figure 1 An example configuration of a wireless communication system according to this embodiment is illustrated. Figure 1 This diagram illustrates a configuration of a communication device including an access point (AP 102) and a site / terminal device (STA 103). Figure 1 As shown, the network formed by AP 102 is illustrated as circle 101. STA 103 is capable of exchanging signals with AP 102. Link 104 represents the communication link between AP 102 and STA 103. Note that this figure illustrates an example, and the following discussion applies to networks comprising multiple communication devices in a wider area and to various locational relationships of the communication devices. Moreover, in this embodiment, an AP (AP 102) is used. However, the invention is not limited to the use of an AP, and it is sufficient for the communication device to have the functionality of adjusting a wireless network, such as an AP.

[0073] AP 102 and STA 103 are capable of performing wireless communication compliant with the IEEE 802.11be (EHT) standard. Note that IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers. AP 102 and STA 103 can communicate at frequencies including 2.4 GHz, 5 GHz, and 6 GHz. The frequency bands used by AP 102 and STA 103 are not limited to these, and different frequency bands such as 60 GHz can be used, for example. Furthermore, AP 102 and STA 103 can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz. The bandwidths used by AP 102 and STA 103 are not limited to these, and different bandwidths such as 240 MHz and 4 MHz can be used, for example.

[0074] Note that in this example, AP 102 and STA 103 are compatible with the IEEE 802.11be standard, but are also compatible with standards prior to IEEE 802.11be. Specifically, AP 102 and STA 103 are compatible with at least one of the IEEE 802.11a / b / g / n / ac / ax standards. Furthermore, in addition to the IEEE 802.11 family of standards, they are also compatible with other standards such as Bluetooth (registered trademark), NFC, UWB, ZigBee, MBOA, etc. Note that UWB is short for UltraWideband, and MBOA is short for Multi Band OFDM Alliance. NFC is short for Near Field Communication. UWB includes Wireless USB, Wireless 1394, WiNET, etc. Moreover, AP 102 and STA 103 are compatible with wired communication standards such as wired LAN. Specific examples of AP 102 include, but are not limited to, wireless LAN routers, personal computers (PCs), etc. Furthermore, AP 102 can be an information processing device, such as a radio chip capable of performing wireless communication compliant with the IEEE 802.11be standard. Specific examples of STA 103 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, camcorders, etc. Furthermore, STA 103 can be an information processing device, such as a radio chip capable of performing wireless communication compliant with the IEEE 802.11be standard. Moreover, as described above, Figure 1The network in this example is configured with a single AP and a single STA. However, the invention is not limited to this number and arrangement of APs and STAs. For example, the network can be configured with a combination of zero APs and two STAs, two APs and zero STAs, or one AP and ten STAs. Note that in the example of this embodiment described herein, IEEE 802.11be is used. However, subsequent standards in the IEEE 802.11 series and other wireless communication standards can be used as long as the invention is applicable to similar techniques.

[0075] As described above, AP 102 and STA 103 can communicate using bandwidths of 20MHz, 40MHz, 80MHz, 160MHz, and 320MHz. Furthermore, AP 102 and STA 103 can perform multi-link communication by utilizing links established via multiple frequency channels. In the IEEE 802.11 series of standards, the bandwidth of each frequency channel is defined as 20MHz. Here, a frequency channel is a frequency channel defined by the IEEE 802.11 series of standards and indicates a frequency channel that can be used to perform wireless communication conforming to the IEEE 802.11 series of standards. In the IEEE 802.11 series of standards, multiple frequency channels are defined in each frequency band, including 2.4GHz, 5GHz, and 6GHz. Note that for a single frequency channel, a bandwidth of 40MHz or greater can be used via channel combination of adjacent frequency channels. For example, AP 102 can establish a first link with STA 103 via a first frequency channel in the 2.4GHz band and a second link via a second frequency channel in the 5GHz band, and perform communication via both links. In this configuration, AP 102 performs multi-link communication, in which a second link via a second frequency channel is maintained in parallel with a first link via a first frequency channel. By establishing links with STA 103 via multiple frequency channels through AP 102 in this way, the throughput of communication with STA 103 can be improved. In multi-link communication, two or more links are established in this manner. However, for simplicity in this embodiment, the only link between AP 102 and STA 103 is link 104.

[0076] When transmitting data between AP 102 and STA 103, AP 102 and STA 103 use data frames that include data units. Furthermore, to confirm which data has been received, Block Acknowledgment (BA) frames and Block Acknowledgment Request (BAR) frames are used. Note that in the following text, BA frames and BAR frames are abbreviated as BA and BAR, respectively. A BA is a frame indicating which of the multiple data frames (data units) received by the receiving side from the transmitting side has been received. A BAR is a frame used to confirm when a BA should be sent to the receiving side of a data frame (data unit). By using BAR and BA, the data sending side can transmit data as a single transmission, which allows for a reduction in the overhead involved in acknowledging frame transmission.

[0077] Furthermore, AP 102 and STA 103 are capable of performing Multiple-Input Multiple-Output (MIMO) communication. In this configuration, AP 102 and STA 103 each include multiple antennas, with the transmitting side emitting different signals from the antennas using the same frequency channel. The receiving side uses antennas to simultaneously receive all signals arriving from multiple streams, separate the stream signals, and decode them. In this way, by performing MIMO communication, AP 102 and STA 103 can transmit a greater amount of data in the same amount of time compared to not performing MIMO communication. Moreover, in the case of multi-link communication, AP 102 and STA 103 can perform MIMO communication at one or more links.

[0078] AP 102 and STA 103 are capable of performing OFDMA communication compliant with the IEEE 802.11be standard. For example, AP 102 can implement multi-user (MU) communication, in which signals addressing multiple users (STAs) are multiplexed. In OFDMA communication, a portion of the allocated frequency band (resource element (RU)) is allocated to each STA without overlap, and the carriers destined for each STA are orthogonal to each other. Therefore, when multiple STAs are present, AP 102 can communicate in parallel with multiple STAs within a specified bandwidth.

[0079] In IEEE 802.11ax, a data transmission method from STA to AP using OFDMA is specified. An example will now be described. When multiple STAs are present, the AP first confirms with each STA whether there is data to be transmitted. The frame used for confirmation at this time is called a Buffer Status Report (BSR) request. In response, each STA transmits the amount of data it expects to send to the AP. The frame used for transmission at this time includes the Buffer Status Report (BSR). Note that this method is an example, and other methods can be used to transmit BSRs to the AP. For example, each STA can send a data frame or a control frame that includes a BSR to the AP. The AP allocates STAs to sub-channels based on the BSRs received from each STA and sends a frame corresponding to the start of data transmission. The frame that serves as the start point is called a trigger frame. The trigger frame includes information about which sub-channel each STA should use to transmit data and information about the guaranteed time period. The STA transmits data to the AP based on the trigger frame information. Therefore, even when multiple STAs are present and the environment is congested, STAs can transmit data while avoiding collisions.

[0080] AP and STA configuration

[0081] Figure 2 This diagram illustrates an example of the hardware configuration of AP 102 according to this embodiment. Note that STA 103 has a similar hardware configuration to AP 102, and only AP 102 will be described here. As an example of the hardware configuration, AP 102 includes a storage unit 201, a control unit 202, a functional unit 203, an input unit 204, an output unit 205, a communication unit 206, and an antenna 207. Note that multiple antennas 207 may be provided.

[0082] Storage unit 201 comprises one or more memories such as ROM or RAM, and stores computer programs for performing the various operations described below, as well as information such as communication parameters for wireless communication. ROM is short for Read Only Memory, and RAM is short for Random Access Memory. Note that, in addition to ROM, RAM, or other such memories, storage media such as floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, DVDs, etc., can be used as storage unit 201. Furthermore, storage unit 201 can be provided with multiple memory devices.

[0083] The control unit 202 is composed of one or more processors (such as a CPU, MPU, etc.) and completely controls the AP 102 by executing a computer program stored in the storage unit 201. Note that the control unit 202 can completely control the AP 102 through the cooperation of the computer program stored in the storage unit 201 and the operating system. Furthermore, the control unit 202 generates data and signals (radio frames) for transmission via communication with other communication devices. Note that CPU is short for central processing unit, and MPU is short for microprocessor unit. Moreover, the control unit 202 can be provided with multiple processors (such as a multi-core processor), and the AP 102 can be completely controlled through multiple processors.

[0084] Furthermore, the control unit 202 controls the functional unit 203 and executes predetermined processes, such as wireless communication, image capture, printing, and projection. The functional unit 203 is hardware used by the AP 102 to execute predetermined processes.

[0085] Input unit 204 receives various operations from the user. Output unit 205 outputs to the user, for example, via a monitor screen or a speaker. In this example, the output via output unit 205 may correspond to displaying on a monitor screen, outputting audio via a speaker, outputting vibration, etc. Note that input unit 204 and output unit 205 may be implemented as a single module, for example, via a touch panel. Moreover, input unit 204 and output unit 205 may be integrally formed with each AP 102 or may be formed separately.

[0086] Communication unit 206 performs control of wireless communication conforming to the IEEE 802.11be standard. Furthermore, in addition to the IEEE 802.11be standard, communication unit 206 can also perform control of wireless communication conforming to another IEEE 802.11 series standard, and can perform control of wired communication using wired LAN, etc. Communication unit 206 controls antenna 207 and transmits and receives wireless communication signals generated by control unit 202.

[0087] It is worth noting that, in addition to the IEEE 802.11be standard, AP 102 is also compatible with NFC, Bluetooth, and other standards, enabling it to perform wireless communication control compliant with these standards. Furthermore, when AP 102 is capable of wireless communication compliant with multiple standards, a configuration can be used where the communication unit and antenna are provided separately for each standard. AP 102 transmits data such as image data, document data, and video data to STA 103 via communication unit 206. Note that antenna 207 can be formed separately from communication unit 206 or can be formed as a single module together with communication unit 206.

[0088] Antenna 207 is an antenna capable of communication in frequency bands including 2.4 GHz, 5 GHz, and 6 GHz. In this embodiment, AP 102 includes one antenna, but three antennas can be provided. Moreover, different antennas can be provided for each frequency band. Furthermore, if AP 102 includes multiple antennas, a communication unit 206 can be provided corresponding to each antenna.

[0089] Figure 3 This diagram illustrates an example of the functional configuration of AP 102 according to this embodiment. It should also be noted that STA 103 has a similar functional configuration to AP 102, and only AP 102 will be described. As an example of the functional configuration, AP 102 includes a wireless LAN control unit 301, a frame control unit 302, a BA control unit 303, a bitmap control unit 304, and a UI control unit 305.

[0090] The wireless LAN control unit 301 includes an antenna and circuitry for transmitting and receiving radio frames (radio signals) with other wireless LAN devices, as well as programs for controlling these. The wireless LAN control unit 301 performs wireless LAN communication control based on frames generated by the frame control unit 302, which conforms to the IEEE 802.11 series of standards. The wireless LAN control unit 301 also has a timing function. Note that the number of wireless LAN control units is not limited to one, and there can be two or more.

[0091] The frame control unit 302 generates radio frames to be transmitted by the wireless LAN control unit 301 or analyzes received radio frames. The content of the generated radio frames can be limited by settings stored in the storage unit 201. Furthermore, the generated radio frames can be changed via user settings from the UI control unit 305.

[0092] The BA control unit 303 sets and confirms the BA format (corresponding to the BAR type described below). The BA control unit 303 can set the BA format using any method. For example, the BA control unit 303 can set the BA format based on radio frames received via the wireless LAN control unit 301. Moreover, the BA format can be set by the AP 102 or input by the user via the input unit 204.

[0093] When the frame control unit 302 receives a data frame, the bitmap control unit 304 confirms the sequence number at this time and generates a bitmap indicating which data unit has been received.

[0094] The UI control unit 305 includes hardware associated with a user interface (such as a touch panel or buttons) for accepting user operations on the AP (not shown), and a program for controlling the hardware. Note that the UI control unit 305 has the function of presenting information to the user via displaying images, outputting audio, etc.

[0095] Processing flow

[0096] Next, the process flow related to data exchange between AP 102 and STA 103 will be described. Figure 6 This is a diagram illustrating the data exchange process in this embodiment. In this embodiment, data is illustrated as being sent from AP 102 to STA 103, but this can be reversed (where data is sent from STA 103 to AP 102). Note that in this embodiment, OFDM is used as the communication method, and the transmission of data frames can be controlled via Enhanced Distributed Channel Access (EDCA).

[0097] When data is transmitted between AP 102 and STA 103, AP 102 and STA 103 use data frames. Furthermore, BAR and BA are used to acknowledge which data has been received. By using BAR and BA, the data sending side can treat data as a single transmission, which allows for a reduction in the overhead involved in frame transmission acknowledgment. Whether to use BAR and how to format BA are determined by the Add Block Acknowledgment (ADDBA) request frame and ADDBA response frame sent and received before transmitting the data frame, as well as the values ​​indicated by the data frame to be transmitted. Note that in the following text, the ADDBA request frame is abbreviated as ADDBA Request, and the ADDBA response frame is abbreviated as ADDBA Response.

[0098] AP 102 sends an ADDBA request (F601) to STA 103 as part of preparation for data transmission. Note that the ADDBA request can be sent from STA 103 to AP 102.

[0099] Example of an ADDBA request, ADDBA request 700, in Figure 7 As shown in the diagram, the fields and subfields in the ADDBA request 700 conform to the format specified in IEEE 802.11ax. Specifically, starting from the beginning, they include the frame control field 701, duration field 702, A1 field 703, A2 field 704, A3 field 705, sequence control field 706, HT control field 707, frame body field 708, and FCS field 709. The frame body field 708 includes a category subfield 710, a block acknowledgment action subfield 711, a block acknowledgment parameter set subfield 712, and a start sequence control subfield 713. The category subfield 710 indicates a value of 3, which indicates that the frame is a block acknowledgment action frame, indicating the start or end of block acknowledgment. The block acknowledgment action subfield 711 indicates a value of 0, which indicates that the frame is an ADDBA request. The block acknowledgment parameter set subfield 712 includes a block acknowledgment policy subfield 715. The block acknowledgment policy subfield 715 is a field used to determine the format of block acknowledgment. When the value of the block acknowledgment policy subfield 715 is 1, the format corresponds to the immediate block acknowledgment format. When the format is immediate block acknowledgment, the data sending side sends the data frame and BAR during the data transmission preparation period. The data receiving side responds to the BAR with a BA. Alternatively, when the value of the block acknowledgment policy subfield 715 is 0, the format corresponds to the delayed block acknowledgment format. When the format is delayed block acknowledgment, the data sending side sends the data frame and BAR during the data transmission preparation period. The data receiving side responds to the BAR with an acknowledgment. The data receiving side then obtains the data frame transmission authorization again and sends a BA, and the data sending side responds to the BA with an acknowledgment. Using the immediate block acknowledgment format, the BA can be performed before the data frame transmission acknowledgment during a single transmission period. Therefore, the overhead involved in data transmission can be reduced. On the other hand, using the delayed block acknowledgment format, it is no longer necessary to perform block acknowledgment processing within a short time period. Therefore, the implementation difficulty can be reduced. In this embodiment, the immediate block acknowledgment format is used. However, the delayed block acknowledgment format can also be used to apply this embodiment.

[0100] The Start Sequence Control subfield 713 includes an Additional Sequence Number subfield 716 and a Start Sequence Number subfield 717. These two subfields are assigned to the sequence number and indicate the sequence number (data unit sequence number) of the next data frame to be transmitted. Note that the Additional Sequence Number subfield 716 was defined as a 4-bit segment number subfield prior to IEEE 802.11ax. It is important to note that the segment number subfield is not assigned to indicate the sequence number, and this also applies to the description below. The Start Sequence Number subfield 717 represents bits 1 through 12, and the Additional Sequence Number subfield 716 represents bits 13 through 16. Using this display format, bits 1 through 12 of the sequence number can be identified even using identification methods prior to IEEE 802.11ax. Note that different display formats can be used. For example, 4 bits can be prepared for the segment number subfield, and 16 bits can be prepared for the subsequent Start Sequence Number subfield 717. In this case, the frame is compatible even if 4 bits are required for a segment number of 0. Alternatively, bits 1 through 4 can be displayed in the additional sequence number subfield 716, and bits 5 through 16 can be displayed in the start sequence number subfield 717. In this way, since there is no discontinuity in the number of bits in the sequence number, the amount of computation performed by the frame receiving side when analyzing the sequence number can be reduced. Furthermore, the value of the block acknowledgment action subfield 711 for displaying the format can be prepared separately. For example, when the value of the block acknowledgment action subfield 711 is 3, this indicates an extended ADDBA request, and the bits used for the start sequence number subfield 717 can be set to 16. In other words, the field length of the start sequence number subfield 717 changes (varies) depending on the value of the block acknowledgment action subfield 711. In this case, since the format of ADDBA specified by IEEE 802.11ax remains unchanged, it makes implementation easier for the device (communication apparatus), which is an advantage. Utilizing a simpler device implementation reduces computational costs within the device, resulting in power savings.

[0101] Furthermore, as mentioned above, the additional sequence number subfield 716 is 4 bits, but it is not limited to this. For example, 2 bits can be allocated to the fragment number subfield, and 2 bits can be allocated to the additional sequence number subfield 716. Alternatively, for example, the starting sequence number subfield 717 prepared as an extended ADDBA request can be set to 20 bits.

[0102] Furthermore, the number of bits in the start sequence number subfield 717 can be changed based on the value indicated by the supplementary sequence number subfield 716. For example, when the first bit of the supplementary sequence number subfield 716 is 1 and the second through fourth bits are 0, the number of bits in the start sequence number subfield 717 can be set to 16 bits. Alternatively, whether the first bit of the supplementary sequence number subfield 716 is 1 can be used as a determination criterion. Thus, even if there are subsequent changes to the start sequence number subfield 717, the system configuration can handle such changes. When it is determined that the frame in the PHY layer is after IEEE 802.11be, the number of bits in the start sequence number subfield can be set to 16 bits. This is also considered to have similar advantages as changing it based on the value of the supplementary sequence number.

[0103] Received with such as Figure 7 The configuration shown in the diagram requests an ADDBA request from STA 103, which then responds with an acknowledgment (F602). STA 103 then sends an ADDBA response (F603). As an example of an ADDBA response, in... Figure 8 The diagram illustrates ADDBA response 800. In ADDBA response 800, fields and subfields 701 to 710 are... Figure 7 The descriptions of those in the ADDBA request 700 shown are similar and are therefore omitted. The value of the block acknowledgment action subfield 711 indicates 1. The configuration of subsequent subfields differs from that in the ADDBA request 700. The ADDBA response 800 includes a status code subfield 801. When the value of the status code subfield 801 is 0, this indicates success and means that the ADDBA request sent by AP 102 has been received. When the value of the status code subfield 801 is any value other than 0, this indicates failure and means that the ADDBA request sent by AP 102 has been rejected. The block acknowledgment parameter set subfield 712 is similar to that in the ADDBA request 700 and is therefore omitted. However, in the block acknowledgment policy subfield 715, the indicated value is the same as the value of the field in the received ADDBA request. In other words, in this embodiment, STA 103 responds with a success in the immediate block acknowledgment format.

[0104] Received with such as Figure 8 The configuration shown in the diagram enables AP 102 to respond with an ADDBA acknowledgment (F604). The processing up to this point is performed before data transmission, and after processing is complete, a delete block acknowledgment (DELBA) process can be performed, or the data transmission and BA transmission processes can be repeated until the connection is closed.

[0105] Subsequently, AP 102 and STA 103 perform data transmission (F605). AP 102 transmits multiple data frames containing data units. In this embodiment, the data frames transmitted at this time have a configuration conforming to IEEE 802.11ax. The QoS control field of the data frame (not shown) includes an acknowledgment policy subfield. This is located in bits 5 and 6 of the QoS control field. In this embodiment, the BA is transmitted after the BAR, and bits 5 and 6 can both be set to 1. Note that this embodiment can have the following configuration: in this configuration, by setting bits 5 and 6 to 0, the data receiving side transmits the BA immediately after the data frame. In this case, the overhead involving the BAR is reduced, but the receiving device needs to respond with the BA in a short amount of time, thereby increasing the implementation complexity. Note that in the data frame, frames other than those described above can have different formats.

[0106] AP 102, having transmitted data, acknowledges the sequence number (F606) of the data unit in the transmitted data frame and sends a BAR (F607). As an example of the BAR sent here, in... Figure 9 The diagram shows BAR 900. Figure 9 The fields and subfields shown conform to the format specified in IEEE 802.11ax. Specifically, BAR 900 includes, from front to back, the Frame Control field 901, Duration field 902, RA field 903, TA field 904, BA Control field 905, BA Information field 906, and FCS field 907. BA Control field 905 includes the BAR Acknowledgment Policy subfield 908, the BAR Type subfield 909, and the TID_INFO subfield 910.

[0107] BAR Acknowledgment Policy Subfield 908 is a field allocated with 1 bit. When the value is 0, the device that received the BAR responds with BA, and when the value is 1, the device that received the BAR does not respond with BA. In this embodiment, the value of BAR Acknowledgment Policy Subfield 908 is 0. Note that this embodiment can still be applied when the value of BAR Acknowledgment Policy Subfield 908 is 1. By not responding with BA, the overhead involving BA can be reduced. Using BA is effective when it can be reliably confirmed that data has been sent.

[0108] BAR type subfield 909 is a subfield indicating the type of BAR. The value of BA information field 906 changes depending on the value. Examples of BAR type values ​​are provided in... Figure 11As shown in the diagram. In this embodiment, the value of the BAR type is 0 (basic). Note that different values ​​can be used. For example, this embodiment can be applied to cases where the value of the BAR type is 3 (multiple TIDs) and a response to a BA is requested in response to multiple TIDs. However, in this case, the subfields included in the subsequent BA information field 906 can be... Figure 9 The subfields shown are different. Furthermore, the subfields indicated by the BA described below can also be different.

[0109] When the value of the BAR type is 0, as in the example of this embodiment, the BA information field 906 includes a start sequence control subfield 911. The start sequence control subfield 911 includes an additional sequence number subfield 912 and a start sequence number subfield 913. These two subfields are fields assigned to the sequence number. Note that the additional sequence number subfield 912 uses a portion of the segment number subfield, which was defined as having a 4-bit length prior to IEEE 802.11ax. The additional sequence number subfield 912 and the start sequence number subfield 913 indicate the sequence number of the data unit initially responded to with a BA. The start sequence number subfield 913 indicates bits 1 through 12, and the additional sequence number subfield indicates bits 13 through 16. Using this display format, bits 1 through 12 of the sequence number can be identified even using identification methods prior to IEEE 802.11ax. Note that different display formats can be used. For example, 4 bits can be prepared for the segment number subfield, and 16 bits can be prepared for the subsequent start sequence number subfield 913. In this case, the frame is compatible even if 4 bits are required for a fragment number of 0. Alternatively, bits 1 through 4 can be displayed in the additional sequence number subfield 912, and bits 5 through 16 can be displayed in the start sequence number subfield 913. In this way, since there is no discontinuity in the number of bits in the sequence number, the amount of computation performed by the frame receiving side when analyzing the sequence number can be reduced. Moreover, the BAR type value for the display format can be prepared separately. For example, when the value of the BAR type subfield 909 is 4, this indicates an extended BAR, and the bits used for the start sequence number subfield 913 can be defined as 16. In other words, the field length of the start sequence number subfield 913 changes according to the value of the BAR type subfield 909. In this case, since the format of ADDBA specified by IEEE 802.11ax remains unchanged, it makes the implementation of the device easier, which is an advantage. Utilizing a simpler device implementation reduces the computational cost in the device, resulting in power savings.

[0110] Furthermore, as mentioned above, the additional sequence number subfield 912 is 4 bits, but it is not limited to this. For example, the fragment number subfield can be set to 2 bits, and the additional sequence number subfield 912 can also be set to 2 bits. Alternatively, for example, the starting sequence number subfield 913, prepared as an extended ADDBA request, can be set to 20 bits.

[0111] Furthermore, the number of bits (field length) in the start sequence number subfield 913 can be changed based on the value indicated by the appended sequence number subfield 912 (or, alternatively, the fragment number subfield). For example, the number of bits in the start sequence number subfield 913 can be set to 16 bits when the first bit of the appended sequence number subfield 912 is 1 and the second through fourth bits are 0. Alternatively, whether the first bit of the appended sequence number subfield 912 is 1 can be used as a determining criterion. Thus, even if there are subsequent changes to the start sequence number subfield 913, the system configuration can handle such changes. When it is determined that the frame in the PHY layer is after IEEE 802.11be, the number of bits in the start sequence number subfield can be set to 16 bits. This is also considered to have similar advantages as changing it based on the value of the appended sequence number.

[0112] When the BAR type value is 1, 2, or 11, the BA information field 906 is as described above. When the BAR type value is 3, a start sequence control subfield is attached to the BA information field 906 for each TID. Specifically, for each TID, a per-TID information subfield and a start sequence control subfield are prepared to indicate which TID it corresponds to. The display method of the start sequence control subfield is as described above, therefore its description is omitted.

[0113] When the value of the BAR type is 6 or 10, the BA information field 906 includes a start sequence control subfield and a GCR group address subfield indicating the group address used to request the reception status. The display method of the start sequence control subfield is as described above, therefore its description is omitted.

[0114] STA 103 has received the sequence number of the received data unit (F608) from the BAR and responded with a BA (F609). As an example of the BA sent at this time, in Figure 10 The diagram shows BAR 1000. Figure 10 The fields and subfields shown conform to the format specified in IEEE 802.11ax. Figure 10 The fields and subfields 1001 to 1009 shown are related to BAR 900 ( Figure 9The description of the BA information field 1006 is similar to that of BAR 900, and therefore omitted. However, the BAR confirmation strategy subfield 1008 and the BAR type subfield 1009 indicate the same values ​​as in BAR 900. When the value of the BAR type in the BAR type subfield 1009 is 0, the BA information field 1006 includes the start sequence control subfield 1010 and the block confirmation bitmap subfield 1011. The start sequence control subfield 1010 is similar to that in BAR 900, and therefore its description is omitted.

[0115] In the Block Acknowledgment Bitmap subfield 1011, the sequence number of the received data unit, relative to the sequence number indicated in the Start Sequence Control subfield 911 of the BAR 900, is associated with and represented by bits. For example, when the sequence number indicated in the Start Sequence Control subfield 911 is 3 and the sequence numbers of the received data units are 3, 5, and 6, the values ​​of bits 1, 3, and 4 are 1, and the rest are 0. Thus, AP 102, having received the BA, can determine what data units STA 103 has received and what data units have not yet received. 128 octets are prepared in the Block Acknowledgment Bitmap subfield 1011. The value is not limited to this. For example, 256 octets can be used.

[0116] When the value of the BAR type is 2, the start sequence control subfield 1010 and the block confirmation bitmap subfield 1011 are prepared in the BA information field 1006. These are 2 octets and 8 octets respectively. The values ​​indicated in these subfields are as described above, so their description is omitted. However, the data indicated here is limited to the same data unit as the TID indicated in the TID_INFO subfield 910 of the BAR.

[0117] When the value of the BAR type is 3, in the BA information field 1006, for each indicated TID, a per-TID information subfield, a start sequence control subfield 1010, and a block confirmation bitmap subfield 1011 are prepared. The per-TID information subfield indicates which TID the sequence number indicated in the subsequent subfield corresponds to. The start sequence control subfield 1010 and the block confirmation bitmap subfield 1011 are described as described above, therefore their description is omitted.

[0118] When the value of the BAR type is 1, the BA information field 1006 includes a start sequence control subfield 1010, a block acknowledgment bitmap subfield 1011, and an RBUFCAP subfield. The start sequence control subfield 1010 and the block acknowledgment bitmap subfield 1011 are described above, therefore their descriptions are omitted. The RBUFCAP subfield indicates the amount of data units that can be received as a buffer.

[0119] When the value of the BAR type is 6 or 10, the BA information field 1006 includes the start sequence control subfield 1010, the GCR group address subfield, and the block acknowledgment bitmap subfield 1011. The start sequence control subfield 1010 and the block acknowledgment bitmap subfield 1011 are described as above, therefore their descriptions are omitted. The GCR group address subfield indicates the group address indicated by the BAR.

[0120] When the BAR type value is 11, the BA information field 1006 is used, and the BA information for each connected STA can be returned in the same frame using the BA information field 1006. Specifically, for each STA, the AID TID information subfield, the start sequence control subfield 1010, and the block acknowledgment bitmap subfield 1011 are repeated. Since the AID TID information subfield includes the AID subfield and specifies the AID corresponding to the STA connected to the AP, the STA can determine which BA is for which STA. 11 is used as the value of the BAR type when the AP is connected to multiple STAs and has received data frames from multiple STAs, and the AP simultaneously sends BAs to multiple STAs. The start sequence control subfield 1010 and the block acknowledgment bitmap subfield 1011 are described as described above, so their description is omitted.

[0121] In this way, by specifying appropriate sequence numbers in the sending and receiving of data, the data receiving side can appropriately determine the initial value of the sequence number, thereby allowing BA processing to continue.

[0122] Next, the processing of AP 102, which acts as the data transmission side, from data transmission (F605) to BA reception (F609) will be described. Figure 4A and 4B This is a diagram illustrating the process flow performed by AP 102. Figure 4A and 4B The flowchart shown can be implemented by the control unit 202 of AP 102 executing the control program stored in the storage unit 201, the calculation and processing of information, and the control of each piece of hardware.

[0123] Figure 4A and 4B The process shown can begin once AP 102 has completed preparations for data transmission. First, the wireless LAN control unit 301 of AP 102 sets the WindowSize to determine the size of the data that can be transmitted at one time (step S401). The WindowSize can be set by any method, such as being preset by AP 102, input by the user via input unit 204, or set based on information received from STA 103. Next, the wireless LAN control unit 301 transmits data to STA 103 (step S402). Figure 6As described in F605, during data transmission, the wireless LAN control unit 301 also includes information indicating whether a BAR is needed. The wireless LAN control unit 301 determines whether to send a BAR based on this information (step S403). When no BAR is needed ("No" in step S403), the wireless LAN control unit 301 waits as is to receive the BAR from STA 103 (steps S410 and S411). When a BAR needs to be sent ("Yes" in step S403), the BAR control unit 303 confirms the BAR type (step S404). The BAR format and processing method differ depending on the BAR type. In this embodiment, the method for confirming the sequence number corresponds to a similar process for all BAR types.

[0124] After confirming the BAR type, the frame control unit 302 confirms the initial sequence number from the data unit to be transmitted. When the initial sequence number is greater than 12 bits ("Yes" in step S406), the frame control unit 302 inputs bits 13 to 16 into the additional sequence number subfield 912 (step S407) and bits 1 to 12 into the start sequence number subfield 913 (step S408). When the initial sequence number is less than 12 bits, the frame control unit 302 only inputs the value into the start sequence number subfield 913.

[0125] Note that in BAR (BAR 900), the processing in steps S406 to S408 differs when the field length of the starting sequence number subfield 913 changes based on the value of the BAR type subfield 909 or the fragment number subfield. In this case, for example, the field to which the sequence number is input can correspond only to the starting sequence number subfield 913. Furthermore, instead of the additional sequence number subfield 912, the fragment number subfield can be set to 4 bits. Therefore, it is no longer necessary to change the field to which the input value is based on the number of bits in the sequence number. This simplifies the processing on the frame receiving side and reduces computational costs. Moreover, existing BA processing can be modified without impact.

[0126] When the values ​​of the BAR type subfield 909 and the start sequence control subfield 911 are determined, the frame control unit 302 generates a BAR, and the wireless LAN control unit 301 performs BAR transmission (step S409). After the BAR is transmitted, the wireless LAN control unit 301 waits for a predetermined amount of time for the BA to be received (steps S410 and S411). If the time for BA reception expires (the predetermined amount of time has elapsed without a BA being received) (yes in step S410), then the wireless LAN control unit 301 retransmits the data (step S420) or terminates the process. When the wireless LAN control unit 301 has received a BA within the predetermined amount of time (no in step S410 and yes in step S411), the BA control unit 303 confirms the BAR type of the received BA (step S412). When the BAR is transmitted in step S403, the BAR type included in the received BA and the BAR type included in the transmitted BAR include the same value.

[0127] Next, the frame control unit 302 confirms the starting sequence number subfield 1013 (step S413) and the additional sequence number subfield 1012 (step S414). Next, the frame control unit 302 determines whether the sequence number is greater than 12 bits from the values ​​of the subfields confirmed in steps S413 and S414 (step S415). When the sequence number is greater than 13 bits ("Yes" in step S415), the frame control unit 302 identifies the sequence number as a value greater than 12 bits (step S416). When the sequence number is not greater than 12 bits ("No" in step S415), the frame control unit 302 identifies the sequence number as a value less than 12 bits (step S417).

[0128] Note that the processing in steps S415 to S417 differs when the field length of the start sequence number subfield 1013 changes based on the value of the fragment number subfield of the BAR type subfield 1009 or the start sequence control subfield 1010. In this case, the frame control unit 302 can confirm the sequence number itself only in the start sequence number subfield 1013. Furthermore, instead of the additional sequence number subfield 1012, the fragment number subfield can be set to 4 bits.

[0129] Next, the frame control unit 302 uses the identified sequence number as a starting point to confirm the sequence number of the data unit received by STA 103 (step S418). When the frame control unit 302 confirms that all data units sent by AP 102 have arrived at STA 103 (yes in step S419), the frame control unit 302 checks whether there is more data to be sent to STA 103 (step S421). If there is more data to be sent (yes in step S421), the process returns to step S401 and AP 102 performs the transmission process again. If there is no more data to be sent (no in step S421), the process ends. In step S419, when the frame control unit 302 determines that there are data units that have not yet been received (no in step S419), the retransmission data of the unreceived data units is added to the next data to be sent (step S420). After this, the process returns to step S401, and AP 102 performs the data transmission process again.

[0130] Next, the processing of STA 103, which acts as the data receiving side, from data reception (F605) to BA transmission (F609) will be described. Figure 5A and 5B This is a diagram illustrating the process flow performed by STA 103. Figure 5A and 5B The flowchart shown can be implemented by the control unit 202 of STA 103 executing the control program stored in the storage unit 201, the calculation and processing of information, and the control of each piece of hardware.

[0131] Figure 5A and 5B The process shown can begin once STA 103 has completed preparation for data reception. First, the wireless LAN control unit 301 of STA 103 sets the WindowSize to determine the size of the data that can be transmitted at one time (step S501). The WindowSize can be set by any method, such as being preset by STA 103, input by the user via input unit 204, or set based on information received from AP 102. Next, the wireless LAN control unit 301 receives data from AP 102 (step S502). See reference... Figure 6As described in F605, the data includes information indicating whether a BAR is needed. The wireless LAN control unit 301 determines whether to receive the BAR based on this information (step S503). When the BAR is not needed ("No" in step S503), the wireless LAN control unit 301 confirms which of the received frames has a sequence number corresponding to the initial sequence number (step S507) and transitions to sequence number input processing (step S512). When the BAR needs to be received ("Yes" in step S503), the wireless LAN control unit 301 waits for the BAR to be received (step S504). When the BAR has been received, the BA control unit 303 confirms the BAR type (step S505). Depending on the BAR type, the BA format and processing method differ. In this embodiment, the method for confirming the sequence number corresponds to a similar process for all BAR types.

[0132] After confirming the BAR type, the frame control unit 302 confirms the start sequence number subfield 913 of the BAR (step S506) and the additional sequence number subfield 912 (step S508). Therefore, for the received data unit, the sequence number corresponding to the initial sequence number is confirmed. When the sequence number is greater than 12 bits, the sequence number is identified as bits 13 to 15 of the additional sequence number subfield 912 and bits 1 to 12 of the start sequence number subfield 913 (step S510). When the sequence number is less than 12 bits, only the value of the start sequence number subfield 913 is confirmed (step S511).

[0133] Note that the processing in steps S509 to S511 differs when the field length of the starting sequence number subfield 913 changes based on the value of the BAR type subfield or the fragment number subfield. In this case, the confirmed sequence number may be solely the sequence number of the starting sequence number subfield 913. Furthermore, instead of the additional sequence number subfield 912, the fragment number subfield can be set to 4 digits.

[0134] When the sequence number of the data unit to be initially received has been confirmed, the frame control unit 302 sets the value of the start sequence control subfield 1010 indicated in the BAR. This value is entered unchanged when the BAR has been received. When the BAR has not yet been received, the sequence number of the data unit to be initially received in the received frame is entered. Note that even when the BAR has been received, the initial sequence number of the data unit correctly received by the STA 103 can be entered. Next, the frame control unit 302 confirms whether the initial sequence number is greater than 12 bits (step S512). When the initial sequence number is greater than 12 bits ("Yes" in step S512), the frame control unit 302 enters bits 13 to 16 into the additional sequence number subfield 1012 (step S513) and enters bits 1 to 12 into the start sequence number subfield 1013 (step S514). When the initial sequence number is no more than 12 bits ("No" in step S512), the frame control unit 302 inputs bits 1 to 12 into the start sequence number subfield 1013 (step S514).

[0135] Note that the processing in steps S512 to S514 differs when the field length of the starting sequence number subfield 1013 changes based on the value of the BAR type subfield or the fragment number subfield. In this case, input can be performed on the starting sequence number subfield 1013. Furthermore, instead of the additional sequence number subfield 1012, the fragment number subfield can be set to 4 bits. Therefore, it is no longer necessary to change the field whose input value is based on the number of bits in the sequence number. This simplifies the processing on the frame receiving side and reduces computational costs. Moreover, existing BA processing can be modified without impact.

[0136] Bitmap control unit 304 uses the sequence number of the data unit, starting with the sequence number, to confirm what has been correctly received (step S515). Bitmap control unit 304 sets the value of the block acknowledgment bitmap subfield corresponding to the sequence number of the correctly received data unit to 1. For example, when the initial sequence number is 3 and the sequence numbers of the correctly received data units are 3, 5, and 6, bits 1, 3, and 4 are set to 1. When it is determined that the values ​​to be entered into BAR type subfield 1009, start sequence control subfield 1010, and block acknowledgment bitmap subfield 1011 are to be entered (step S516), frame control unit 302 generates a BA, and wireless LAN control unit 301 sends the BA and ends the process (step S517).

[0137] Therefore, even as the number of characters assigned to the sequence number increases, data transmission and acknowledgment from AP 102 to STA 103 are still performed.

[0138] Modified example

[0139] In the example above, data is sent from AP 102 to STA 103. However, such a limitation is not intended. For example, data can be sent from STA 103 to AP 102. Moreover, a configuration in which AP 102 and STA 103 support multiple links and the multiple links use a common sequence number can be used. In this way, throughput can be reasonably further improved. Furthermore, when AP 102 is connected to multiple STAs and simultaneously receives data frames from the STAs, the ADDBA request, ADDBA response, BAR, and BA according to the above embodiment can be applied. In this way, since multiple STAs send frames simultaneously, efficient radio wave transmission and reception can be achieved even when sending large amounts of data. Moreover, after the processing of the ADDBA request and ADDBA response, either DELBA processing can be performed or data transmission and reception can be repeated until the connection is cut off. This applies even when the BAR type changes during data communication. In this way, even when the type of data to be sent from AP 102 to STA 103 changes from unicast to multicast, data transmission and reception can continue without performing ADDBA processing again, and processing overhead can be reduced.

[0140] In the above embodiments, the appended sequence number subfield 716 was defined as a 4-bit segment number subfield prior to IEEE 802.11ax. However, such a restriction is not intended. For example, in BAR, BA, ADDBA request, and ADDBA response, one byte may begin at the end of the start sequence control subfield. In other words, one byte following the start sequence control subfield can be used to indicate the initial sequence number. In this case, the GCR group address element, multi-band, TCLAS, or ADDBA extension may begin at the end, but they can be appended before or after it.

[0141] Furthermore, in an ADDBA request, the Additional Serial Number subfield 716 can be defined as an element of the ADDBA extension element. Similarly, in BAR and BA, the Additional Serial Number subfield can be placed after the Start Sequence Control subfield or the Block Confirmation Bitmap subfield. Moreover, an extension element can be defined after the Block Confirmation Bitmap field, indicating the ID, length, and value of the Additional Serial Number. Thus, the number of digits that can represent the serial number can be increased without changing the existing field format.

[0142] In this way, even as the maximum value of the sequence number increases, the BAR or BA can be sent to the buddy device with the initial sequence number of the data unit (data frame) associated with the transmission represented. Note that the terms "subfield" and "field" used in the above example are conventional terms, and a subfield can be referred to as a field. For example, a start sequence number field, a block confirmation action field, a BAR type field, etc., can be used.

[0143] Other embodiments

[0144] This invention can be implemented by supplying a program for implementing one or more functions of the above embodiments to a system or device via a network or storage medium, and causing one or more processors in the computer of the system or device to read and execute the program. This invention can also be implemented by a circuit (e.g., an ASIC) for implementing one or more functions.

[0145] This invention is not limited to the above embodiments, and various changes and modifications can be made within the spirit and scope of this invention. Therefore, in order to inform the public of the scope of this invention, the following claims are made.

Claims

1. A communication device, the communication device conforming to the IEEE 802.11 series of standards, characterized in that... include: A data transmission component is used to continuously and repeatedly transmit multiple data frames to another communication device, each data frame including a data unit; The generation component is used to generate the Block Confirmation Request (BAR) frame. BAR transmitting component, used to transmit the BAR frame to the other communication device after the transmission of the plurality of data frames in succession; as well as A receiving component is configured to receive, from the other communication device, a Block Acknowledgment (BA) frame as a response to the BAR frame, wherein The BAR frame uses a predetermined field to indicate the sequence number of a data unit in the initial data frame among multiple consecutively transmitted data frames, and The predetermined fields in the BAR frame include a segment number field and a start sequence number field. The number of digits in the starting sequence number field changes according to the value indicated by the segment number field. If the first to fourth bits of the segment number field are not 1, 0, 0, 0, the segment number field indicates that the starting sequence number field is set to 12 bits, and When the first bit of the fragment number field is 1 and the second to fourth bits are 0, the fragment number field indicates that the number of bits in the start sequence number field is set to 16 bits, wherein the 16-bit start sequence number field includes the 12-bit start sequence number field before extension and a 4-bit additional field, which is different from the fragment number field, and in the BAR frame, the 16-bit start sequence number field follows the 4-bit fragment number field.

2. A control method for a communication device, the communication device conforming to the IEEE 802.11 series standards, characterized in that... include: Multiple data frames are sent to another communication device in succession, each data frame including a data unit; Generate a Block Acknowledgment Request (BAR) frame; The BAR frame is sent to the other communication device after a series of transmissions of the plurality of data frames; as well as Receive a Block Acknowledgment (BA) frame as a response to the BAR frame from the other communication device, wherein In the generation process, the sequence number of the data unit in the initial data frame of the plurality of data frames transmitted in multiple consecutive transmissions is indicated using a predetermined field in the BAR frame, and The predetermined fields in the BAR frame include a segment number field and a start sequence number field. The number of digits in the starting sequence number field changes according to the value indicated by the segment number field. If the first to fourth bits of the segment number field are not 1, 0, 0, 0, the segment number field indicates that the starting sequence number field is set to 12 bits, and When the first bit of the fragment number field is 1 and the second to fourth bits are 0, the fragment number field indicates that the number of bits in the start sequence number field is set to 16 bits, wherein the 16-bit start sequence number field includes the 12-bit start sequence number field before extension and a 4-bit additional field, which is different from the fragment number field, and in the BAR frame, the 16-bit start sequence number field follows the 4-bit fragment number field.

3. A computer-readable storage medium storing a program for causing a computer to execute a control method for a communication device conforming to the IEEE 802.11 series of standards, characterized in that... include: Multiple data frames are sent to another communication device in succession, each data frame including a data unit; Generate a Block Acknowledgment Request (BAR) frame; The BAR frame is sent to the other communication device after a series of transmissions of the plurality of data frames; as well as Receive a Block Acknowledgment (BA) frame as a response to the BAR frame from the other communication device, wherein In the generation process, the sequence number of the data unit in the initial data frame of the plurality of data frames transmitted in multiple consecutive transmissions is indicated using a predetermined field in the BAR frame, and The predetermined fields in the BAR frame include a segment number field and a start sequence number field. The number of digits in the starting sequence number field changes according to the value indicated by the segment number field. If the first to fourth bits of the segment number field are not 1, 0, 0, 0, the segment number field indicates that the starting sequence number field is set to 12 bits, and When the first bit of the fragment number field is 1 and the second to fourth bits are 0, the fragment number field indicates that the number of bits in the start sequence number field is set to 16 bits, wherein the 16-bit start sequence number field includes the 12-bit start sequence number field before extension and a 4-bit additional field, which is different from the fragment number field, and in the BAR frame, the 16-bit start sequence number field follows the 4-bit fragment number field.

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