Communication device, its control method, and program

Abstract

To solve the problem in a possibility that appropriate communication processing cannot be performed when a conventional communication method in one by one is adopted in a case where a plurality of communication apparatuses performs communication of data in cooperation.SOLUTION: A communication apparatus that is communicated with a first other communication apparatus and a second other communication apparatus, comprises: first execution means of performing setting for receiving data in cooperation with the first other communication apparatus; second execution means of performing setting for transmitting a BA (Block Ack) in delay with the second other communication apparatus; first transmission means of transmitting the Ack to the second other communication apparatus in the case where at least part of first data transmitted from the second other communication apparatus is received; and second transmission means of transmitting the BA after the Ack transmission by the first transmission means to the second other communication apparatus in the case where at least part of the first data received by the first other communication apparatus is received from the first other communication apparatus.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a communication apparatus conforming to the IEEE 802.11 standard. [Background Art]

[0002] As a communication standard for wireless local area networks (Wireless Local Area Network, hereinafter referred to as WLAN), the IEEE 802.11 series of standards are well known. The latest standard, the IEEE 802.11be standard, uses Multi-Link technology to achieve low-latency communication in addition to high peak throughput (Patent Document 1).

[0003] In addition, in order to achieve throughput improvement, a method is disclosed in which transmission data for a single station (STA) is allocated to a plurality of spatially distributed access points (APs), and these APs transmit the data to the STA in parallel (Patent Document 2). [Prior Art Literature] [Patent Literature]

[0004] [Patent Document 1] US Patent Application Publication No. 2021 / 0211375 Specification [Patent Document 2] Japanese Unexamined Patent Application Publication No. 2020-141300 [Summary of Invention] [Problem to be Solved by Invention]

[0005] Configurations in which a plurality of APs cooperatively receive data transmitted from a single STA are also being studied. In such a case, there was a possibility that appropriate communication processing could not be performed if the conventional one-to-one communication method is followed.

[0006] In view of the above, an object of the present invention is to provide a method capable of appropriately performing communication processing even when a plurality of communication apparatuses perform data communication cooperatively. [Means for solving the problem]

[0007] A communication device that communicates with a first other communication device and a second other communication device, comprising: a first execution means for setting up the first other communication device to receive data in cooperation with the first other communication device; a second execution means for setting up the second other communication device to send a delayed BA (Block Ack); a first transmission means for sending an Ack to the second other communication device when it receives at least a portion of the first data transmitted from the second other communication device; and a second transmission means for sending a BA to the second other communication device after the Ack transmission by the first transmission means when the first other communication device receives at least a portion of the first data received by the first other communication device from the first other communication device. [Effects of the Invention]

[0008] When multiple communication devices cooperate to communicate data, it becomes possible to process the communication appropriately. [Brief explanation of the drawing]

[0009] [Figure 1] system configuration diagram [Figure 2] Device configuration diagram (hardware) of this embodiment [Figure 3] Functional configuration diagram of this embodiment (software) [Figure 4] Sequence diagram of Embodiment 1 of this embodiment [Figure 5] Diagram showing MAC frame structure [Figure 6] Diagram showing the structure of the HT Capabilities element. [Figure 7] Diagram showing the structure of Actionframe [Figure 8] Diagram showing actions related to Multi-AP [Figure 9] A diagram showing Block Ack-related actions. [Figure 10]A diagram showing the structure of a block ack frame. [Figure 11] Flowchart showing the processing on the Master AP side. [Figure 12] Sequence diagram of Embodiment 2 of this embodiment [Modes for carrying out the invention]

[0010] The system of this embodiment will be explained using Figure 1. 101 is AP (Access Point) 1, and 102 is a schematic representation of the area where AP1's radio waves can reach. The network formed by APs is sometimes referred to as BSS (Basic Service Set). Here, AP1 (101) constitutes BSS1. Similarly, 103 is AP2, which is different from AP1 (101), and 104 is a schematic representation of the area where AP2 (103)'s radio waves can reach. AP2 (103) constitutes BSS2.

[0011] 105 is a Distribution System (DS) that extends the connections between each BSS. This is sometimes called a backhaul. APs connect to other BSSs and external networks via this DS. This connection method can be wired communication such as Ethernet® or telephone lines, or wireless communication such as LTE (Long-Term Evolution) or WiMAX (Worldwide Interoperability for Microwave Access). Furthermore, it may also be a wireless LAN compliant with the IEEE 802.11 standard. In this case, the connection between the AP and other BSSs or external networks may be the same as or different from the wireless channel used between the AP and the terminal. AP1 (101) and AP2 (103) can connect via the DS and cooperate in receiving and transmitting data.

[0012] 106 is a station terminal (STA) connected to AP1 (101). Here, AP2 (103) is within the communication range of STA (106), but STA (106) is not connected to AP2 (103).

[0013] 107 is a terminal that serves as an interference source affecting data reception of AP1 (101). This terminal (107) is not necessarily a terminal compliant with the IEEE 802.11 standard, and does not have to be a communication terminal in the sense that it cannot be controlled by AP1. 108 indicates the interference range of the terminal (107), and indicates the range affected by radio waves.

[0014] APs 101 and 103 are successor standards to the IEEE 802.11be standard that targets a maximum transmission rate of 46.08 Gbps, and are configured to be capable of performing wireless frame communication compliant with the successor standard that targets a maximum transmission rate exceeding 90 Gbps to 100 Gbps. Similarly, STA 106 is also configured to be capable of performing wireless frame communication compliant with said successor standard.

[0015] Note that IEEE is an abbreviation for Institute of Electrical and Electronics Engineers. The successor standard to 802.11be lists support for highly reliable communication, low-latency communication, and AP coordination as its main features. Based on the above, in the present embodiment, the successor standard to IEEE 802.11be that targets a maximum transmission rate exceeding 90 Gbps to 100 Gbps is also referred to as IEEE 802.11 UHR (Ultra High Reliability). Furthermore, a wireless frame communicated in accordance with said successor standard is also referred to as a UHR PPDU. PPDU is an abbreviation for PLCP Protocol Data Unit, and PLCP is an abbreviation for Physical Layer Convergence Protocol.

[0016] It should be noted that the names IEEE802.11UHR and UHR standard are provided for convenience based on the objectives to be achieved in the successor standard and the key features of the standard, and may be changed to other names after the standard development is completed. On the other hand, it should be noted that the present specification and the appended claims are essentially applicable to any successor standard to the 802.11be standard that can support the function of performing processing for receiving data from a STA through coordination between a plurality of APs.

[0017] FIG. 2 shows a hardware configuration commonly applicable to APs and STAs (non-AP terminals) in the present embodiment. As an example of the hardware configuration, the device includes a storage unit 201, a control unit 202, a function unit 203, an input unit 204, an output unit 205, a communication unit 206, and an antenna 207.

[0018] The storage unit 201 is constituted by a memory such as ROM or RAM, and stores programs for performing various operations described below and various types of information such as communication parameters for wireless communication. In addition to memories such as ROM and RAM, a storage medium such as a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a non-volatile memory card, or a DVD may be used as the storage unit 201. Furthermore, the storage unit 201 may include a plurality of memories or the like.

[0019] The control unit 202 is composed of, for example, a processor such as a CPU or MPU, an ASIC (Application-Specific Integrated Circuit), a DSP (Digital Signal Processor), or an FPGA (Field-Programmable Gate Array). Here, CPU is an acronym for Central Processing Unit, and MPU is an acronym for Micro Processing Unit. It controls the AP by executing a program stored in the memory unit 201. The control unit 202 may also control the AP in cooperation with the OS (Operating System) and the program stored in the memory unit 201. Alternatively, the control unit 202 may consist of multiple processors, such as a multi-core processor, to control the AP. Furthermore, the control unit 202 controls the function unit 203 to execute predetermined processes such as AP functions, STA functions, imaging, printing, and projection.

[0020] The functional unit 203 is hardware that allows the AP or STA to perform predetermined processing. For example, if the functional unit is a printer, it prints the image data acquired via the communication unit 206. If the functional unit is a scanner, it transmits the image data generated by scanning via the scanner to an external device via the communication unit 206. If the functional unit is a camera, it transmits the image data captured by the camera to an external device via the communication unit 206.

[0021] The input unit 204 receives various operations from the user. For example, it may consist of a touch panel, hard keys, buttons, etc.

[0022] The output unit 205 provides various outputs to the user. These outputs include at least one of the following: display on a screen, audio output from a speaker, vibration output, etc. Alternatively, both the input unit 204 and the output unit 205 may be implemented in a single module, similar to a touch panel.

[0023] The communication unit 206 controls wireless communication compliant with IEEE 802.11, wireless communication compliant with Wi-Fi®, and IP (Internet Protocol) communication. Furthermore, the communication unit 206 controls the antenna 207 to transmit and receive wireless signals for wireless communication. It may also be configured to perform NFC communication or Bluetooth® communication.

[0024] In the diagram, only one antenna 207 is shown for simplification, but multiple antennas may be provided. Generally, the number of antennas corresponds to the number of spatial streams. The number of communication units 206 and antennas 207 corresponds to the corresponding frequency bands (2.4GHz, 5GHz, and 6GHz) and the corresponding number of streams.

[0025] Figure 3 shows an example of the functional (software) configuration of an AP or STA. Here, as an example, it includes a wireless LAN control unit 301, a Single-AP control unit 302, a Multi-AP control unit 303, a Joint Reception control unit 304, a Block Acknowledgment control unit 305, a storage unit 306, and a UI control unit 307.

[0026] The wireless LAN control unit 301 is configured to include circuits for sending and receiving wireless signals with other wireless LAN devices (e.g., other APs and STAs) and programs for controlling them. This configuration of the wireless LAN control unit 301 enables it to perform wireless LAN communication control, such as frame generation and transmission, and reception of wireless frames from other wireless LAN devices, in accordance with the IEEE 802.11 standard series.

[0027] The Single-AP control unit 302 is a functional unit that controls the AP to operate independently of other APs.

[0028] The Multi-AP control unit 303 controls the synchronization and cooperative operation with other APs. It performs configuration processes with other APs in order for the AP to cooperate with them. The Joint Reception control unit 304 is a functional unit that performs data reception in cooperation with other APs. Joint Reception is a process that controls multiple communication devices to cooperate in receiving data from the opposing device, and it acquires a single integrated version of the data received by multiple communication devices.

[0029] The Block Acknowledgment (BA) control unit 305 controls BA communication. It also works in conjunction with the Joint Reception control unit to control procedures, including the transmission of Block Acknowledgment frames. Block Acknowledgment is also referred to as Block Ack or BA.

[0030] The memory unit 306 includes storage devices such as ROM (Read Only Memory) and RAM (Random Access Memory) for storing programs executed by AP and STA, as well as various data.

[0031] The UI control unit 307 includes hardware related to a user interface (UI), such as a touch panel or buttons, for receiving operations on the AP and STA by users of the AP and STA, and a program to control them. The UI control unit 307 also has functions for presenting information to the user, such as displaying images or outputting audio.

[0032] <Example 1> The sequence of operations in the first embodiment will be explained using the sequence diagram in Figure 4.

[0033] In Figure 4(a)401, AP1(101) sends a Multi-AP setup request to AP2(103).

[0034] In response 402, AP2 (103) sends a Multi-AP setup response to AP1 (101).

[0035] Procedures 401 and 402 are settings for multiple APs to cooperate in data communication. Here, AP1 (101) is assumed to be the Coordinator AP, and AP2 (103) is assumed to be the Coordinated AP. The Coordinator AP is the AP that controls the Multi-AP configuration and operation, and is sometimes called a sharing AP because it shares wireless media resources with other APs to perform cooperative operation. Similarly, the Coordinated AP is sometimes called a Shared AP.

[0036] Furthermore, 401 and 402 also perform verification and notification to determine if they have the capability to perform Joint Recetion processing. For example, they verify whether they have the capability to perform Joint Recetion processing by checking whether they comply with the specified standards of the IEEE 802.11 series standards. The types of setup and verification / notifications here will be described later in Figure 8.

[0037] In 403, AP1(101) broadcasts a Beacon. This is generally broadcast at a fixed interval, such as every 100 milliseconds. The management frames for Beacon, Probe Request / Response, and Association Request / Response (described later) can include various IEs (Information Elements) indicating Capability and Operation. In this invention, AP1(101) broadcasts that it is operating in a Multi-AP configuration and that it has Joint Reception capability. AP1(101) and STA(106) each include an IE indicating that they have Delayed Ack capability. Here, Delayed Ack refers to a delayed transmission of a BA, and Delayed Ack capability is the ability to transmit a BA with a delay. For example, if a communication device complies with the specified standards of the IEEE 802.11 series standard, it is assumed to have Delayed Ack capability.

[0038] Upon receiving a 404 error, STA(106) sends a Probe Request to AP1(101). STA(106) may also include information in the Probe Request indicating whether STA(106) has Delayed Ack capability.

[0039] In a 405 error, AP1(101) notifies AP2(103) that STA(106) is a target for capture and instructs AP2(103) to capture. "Capture" means that when a frame is received from a terminal that is not connected to AP, AP2(103) holds the received frame so that it can be forwarded to other APs, at least at the MAC level. "Capture" is sometimes called "snoop". This notification is performed by an 803 error, which will be described later. Here, as an example of capture, AP2(103) receives and holds a frame sent by STA(106), which does not have a communication connection established with AP2(103). AP2(103) then forwards the held frame to AP1(101). Not being connected to AP2 means, for example, not having exchanged Association Request / Response messages or not having performed a 4-way Handshake. This capture instruction makes it possible for AP1(101) and AP2(103) to coordinately receive the data sent by STA(106).

[0040] With a 406 error, AP1(101) returns a Probe Response to STA(106).

[0041] In response 407, STA(106) sends an Association Request to AP1(101).

[0042] At 408, AP2(103) captures the frame transmitted at 407.

[0043] At step 409, AP1 (101) sends a confirmation signal to AP2 (103) to check whether or not it has captured a frame from STA (106).

[0044] In step 410, AP2(103) sends a capture acknowledgment to AP1(101). Here, if AP2(103) received the Association Request sent in step 407, AP2(103) sends an affirmative response back to AP1(101); otherwise, it sends a negative response back to AP1(101).

[0045] In 411, AP1(101) returns an Association Response to STA(106).

[0046] Subsequently, AP1(101) and STA(106) perform a 4-way handshake according to the encryption settings. As a result, AP1(101) and STA(106) share a PMK (Pairwise Master Key), and AP1(101) generates a GTK (Group Temporal Key). In this invention, AP2(103) does not share or hold these encryption keys.

[0047] With the steps taken so far, we have established an environment in which AP1(101) and AP2(103) can perform Joint Reception, taking into account STA(106)'s Delayed Ack capability.

[0048] The Delayed Ack capability required for Joint Reception processing is provided by either the HT-delayed Block Acknowledgment capability or a newly defined capability for the successor standard to 802.11be. The implementation of Delayed Ack will utilize the mechanism defined in the IEEE 802.11 series standards to delay the transmission of the Block Acknowledgment (BA).

[0049] The following Figure 4(b) from 412 onwards shows the procedure after 411, which is the data transmission procedure from STA(106) to AP1(101).

[0050] At port 412, communication data is generated within STA(106).

[0051] In step 413, STA(106) sends an ADDBA Request to AP1(101). ADDBA is a procedure for receiving and responding to multiple frame transmissions, and it is used to configure settings related to BA. ADDBA is defined in the Action frame shown in Figure 9. In other words, here STA(106) sends an ADDBA Request to AP1(101) requesting that AP1(101) perform the process of sending a BA with a delay, in this case the process of sending a Delayed Ack.

[0052] In 414, AP2(103) captures the ADDBA Request sent in 413.

[0053] At step 415, AP1(101) sets the Block bit (905) of the ADDBA Response frame to "0 (zero)" and returns the ADDBA Response frame to STA(106). At this time, the Status Code (906) is set to "SUCCESS". As a result, the Block Acknowledgment procedure using Delayed Ack is applied to the data exchange between STA(106) and AP1(101).

[0054] At 416, STA(106) sends the data generated at 402 in A-MPDU (Aggregate Medium Access Control Protocol Data Unit) format. Although not shown in the diagram, AP1(101) starts an inactivity timer upon receiving this A-MPDU. When this timer times out (expires), the ADDBA procedure established between 413 and 414 is deleted.

[0055] At 417, AP2(103) captures the A-MPDU transmitted at 416.

[0056] At 418, interference from terminal (107) occurs. This interference affects frame reception on AP1 (101). In this case, it affects the reception of the A-MPDU transmitted at 416.

[0057] In step 419, STA(106) sends a BAR (Block Acknowledgment Request) to AP1(101).

[0058] On port 420, AP2(103) captures the BAR transmitted on port 419.

[0059] At step 421, AP1 (101) notifies STA (106) that it has received the BAR by sending an Ack (normal Ack). The reason it can return an Ack instead of a BA (Block Acknowledgment) is because the Block Acknowledgment Policy bit (905) is set to 0 (zero) at step 415.

[0060] At 422, AP2(103) sends the A-MPDU payload captured at 417 to AP1(101). This payload consists of a group of MSDUs (Medium Access Control Service Data Units) at the MAC layer level. This payload transfer at 422 is performed via DS(105).

[0061] At 423, AP1(101) organizes and integrates the A-MPDU data received at 416 and the data received at 422 in sequence number order.

[0062] At 424, AP1 (101) generates a Block Acknowledgment (BA) based on the processing in 423 and sends it to STA (106). In other words, the Delayed Ack processing allows the BA for the A-MPDU sent in S416 to be delayed to the timing of 424, rather than immediately after 416.

[0063] At 425, STA(106) sends an Ack to AP1(101).

[0064] The process from 412 to 425 completes the series of A-MPDU transmission steps. However, if there is still transmission data remaining in STA(106), STA(106) will proceed from step 416. Alternatively, the Block Ack parameter can be changed to start from step 413.

[0065] As described above, when multiple APs respond to data received collaboratively by the STA, delaying the BA transmission to the STA allows for appropriate data transmission response processing.

[0066] Figure 5 shows the structure of an 802.11 MAC frame. 500 represents the entire MAC frame. For general explanation, Octets and Bits indicate the size of each field. Fields labeled "variable" are of variable length.

[0067] 501 is a Frame Control, which in detail consists of Subfields 512 through 522.

[0068] 502 represents Duration, with a length of 2 octets (16 bits). When indicating time, such as frame length or TXOP, the MSB (Most Significant Bits: B15) is "1", and the remaining 15 bits represent a range from 0 to 32767 microseconds.

[0069] Fields 503, 504, 505, and 507 are Address fields. The BSSID, source, and destination addresses are set according to the MAC frame type (Type 513) and subtype (Subtype 514). Note that the Address field used differs depending on the type.

[0070] 506 is Sequence Control.

[0071] 508 is QoS Control. The BSR (Buffer Status Report) from standards prior to 802.11ax is included here as two pieces of information.

[0072] 509 is HT Control.

[0073] 510 is the Frame Body. If type (522) is a Management Frame, that is, in Beacon or Probe Request / Response, various IEs (Information Elements) are placed at this field location.

[0074] 511 is FCS (Frame Check Sequence).

[0075] 512 is a 2-bit number that indicates the Protocol Version, which is "0" for 802.11 frames.

[0076] 513 is a 2-bit number that indicates the Type, representing Management, Control, or Data.

[0077] 514 is a 4-bit number that indicates the subtype, further classifying the Management, Control, and Data types.

[0078] Bit 515 indicates "To DS," meaning the frame's destination is the Distribution System (DS).

[0079] 516 is the number of bits that indicates "From DS".

[0080] 517 is the bit that indicates More Fragment.

[0081] 518 is the bit that indicates a retry.

[0082] Bit 519 indicates Power Management.

[0083] 520 is a bit that indicates More Data.

[0084] 521 is the bit that indicates a Protected Frame.

[0085] 522 is the bit that indicates +HTC.

[0086] Here, the frames that can have the +HTC bit set, i.e., frames that can contain the HT Control field, are QoS Data, Management, and RTS frames. There are further detailed conditions, but these are omitted here.

[0087] Figure 6 shows an HT Capabilities element, which consists of eight fields. This element is included in Management frames such as Beacon, Probe Request / Probe Response, and Association Request / Association Response.

[0088] 601 is the Element ID, and its value is 45. For the sake of simplicity, fields relevant to this embodiment are denoted by reference numerals and described accordingly; fields without reference numerals are omitted from the description.

[0089] 603 is an HT Capability Information field with a length of 2 octets.

[0090] 617 is an HT-delayed Block Acknowledgment with a length of 1 bit. By setting this bit to "1", the AP and STA of the present invention indicate that they have the ability to send a Delayed Ack to the BAR, that is, the ability to handle procedures that do not return an immediate BA. In this embodiment, it is also used by the AP to determine whether the STA is capable of handling a Joint Reception operation.

[0091] When indicating Delayed Ack capability using the UHR Capabilities element, it will be determined using the same element as in Figure 6.

[0092] Figures 7(a) and 7(b) show the structure of the Action frame.

[0093] An Action frame is a type of Management frame, where the MAC frame's Frame Control 501 (2 octets) has Type 513 (B3-B2) set to "00" and Subtype 514 (B7-B4) set to "1101".

[0094] The frame body of an Action frame consists of Category701 (1 octet) and Action Details702 (variable length).

[0095] As shown in Figure 7(c), Category 701 indicates the meaning of the Action. Currently, in 802.11be Draft 2.3, the values ​​(Codes) for Category 701 are defined from "0: Spectrum Management" (703) to "37: Protected EHT" (706). For example, there are "3: Block Ack" (704) and "36: EHT" (705). The Block Ack-related Action Frame, which will be discussed later, has Category "3". Here, "38: UHR" (707) is also newly defined. Action Details are defined for each of these Categories.

[0096] In this embodiment, the procedure for Multi-AP is performed by adding an Action to the EHT Protected Category or by defining a new Category for UHR. Here, Multi-AP refers to a system in which multiple APs cooperate to perform data communication.

[0097] Figure 8(a) shows the structure of a Multi-AP related Action frame. In this example, it is a UHR (Category=38) frame. Figure 8(b) shows the values ​​of "Multi-AP Action field values" and their corresponding Meanings. It is assumed that the communication device sets and transmits appropriate values.

[0098] In 801, if the "Multi-AP Action field values" are "0", it indicates that the frame is a Multi-AP setup request. This frame is the Action that the Coordinator AP sends to the Coordinated AP candidate when building a Multi-AP.

[0099] Similarly, 802 indicates a Multi-AP setup response, and this frame is a response to frame 801. It is also possible to negotiate the roles of the Coordinator AP and Coordinated AP by exchanging frames 801 and 802.

[0100] 803 is a Multi-AP coordination parameter indication, an Action in which the Coordinator AP notifies of an update to the coordinate operation parameters. These parameters can be used to configure the coordinate operation method, including Joint Reception in this embodiment, as well as JTX (Joint Transmission), null steering, and Coordinated OFDMA (Orthogonal Frequency Division Multiple Access).

[0101] Furthermore, detailed parameters for the Joint Reception process include items such as the MAC address of the target STA terminal and the operating frequency band (2.4 / 5 / 6GHz).

[0102] 804 is a Multi-AP tear-down indication, an action in which a Coordinator AP or Coordinated AP notifies that the Multi-AP coordinated operation has ended.

[0103] When performing the series of procedures related to Multi-AP via DS105, frame formats such as Ethernet®, telephone lines, LTE, and WiMAX will be used, but even in that case, the concept of the MAC layer (Layer 2) remains the same as in the format shown in Figure 8.

[0104] Figure 9 illustrates the Action frame related to Block Acknowledgment. Figure 9(a) shows the Action Field Format, where the Category is "3".

[0105] Figure 9(b) Block Ack Action field values ​​shows the field values ​​and their corresponding Meanings.

[0106] 901 indicates an ADDBA Request, and 902 indicates an ADDBA Response. These are used to negotiate how the Block Ack process will be carried out.

[0107] 903 is used in DELBA to indicate that the Block Ack procedure will not continue.

[0108] Figure 9(c) shows the information contained in an ADDBA Request when the frame is an ADDBA Request. Similarly, Figure 9(d) shows the information contained in an ADDBA Response when the frame is an ADDBA Response.

[0109] The Block Ack Parameter Set for error 904 is information contained within the ADDBA Request frame and ADDBA Response frame.

[0110] Details of 904 are shown in Figure 9(e) Block Ack Parameter Set. The Block Ack Parameter Set has a Block Ack Policy field (905). When this bit is "1", it indicates an Immediate Block Ack, and when it is "0", it indicates a Delayed Block Ack, and is used during negotiation regarding the Block Ack. If it is an Immediate Block Ack, the Block Ack will be returned immediately upon data reception, and if it is a Delayed Block Ack, the Block Ack will be returned with a delay after data reception.

[0111] 906 is a two-octet Status Code that indicates the Information contained in the ADDBA Response. When this value is "0", it is an affirmative response to the ADDBA Request.

[0112] Figures 10(a) to 10(c) show the structure of the Block Ack Request frame and the Block Ack frame. Figure 10(a) shows the overall structure of the Block Ack Request frame and the Block Ack frame, and the fields that make up the frame are Frame Control 501 and Duration 502, two Addresses (Receiver Address and Transmitter Address (neither shown in the figure)), Frame Body 510 (BA Control and BA Information), and FCS 511.

[0113] Figure 10(b) shows the structure of the BA Control field. The BA Control field includes the BA Ack Policy subfield (1001), Multi-TID subfield (1002), Compressed Bitmap subfield (1003), GCR subfield (1004), Reserved subfield (1005), and TID_INFO subfield (1006).

[0114] Figure 10(c) shows the BA Information field, which includes Block Ack Starting Sequence Control (1007) and Block Ack Bitmap (1008). Block Ack Starting Sequence Control (1007) and Block Ack Bitmap (1008) indicate which MSDU (Medium Access Control Service Data Unit) was received. As this embodiment follows the prior art, no further explanation of the BA frame itself is provided.

[0115] Figure 11 is a flowchart showing the process when AP1(101) performs Multi-AP configuration and Joint Reception processing, and it illustrates the processing on the Coordinator AP side. For example, it is a flowchart that is realized when one or more processors execute a program stored in one or more memory. Note that the AP processing corresponding to each step of the sequence in Figure 4 will be numbered after S. For example, the AP processing corresponding to processing 401 in Figure 4 will be expressed as S401 in this flowchart.

[0116] At S401, AP1(101) sends a Multi-AP setup request to AP2(103). Then, at S402, AP1(101) receives a Multi-AP setup response from AP2(103).

[0117] At S403, AP1(101) transmits beacons containing various IEs. Then, at S404, it receives a Probe Request from STA(106).

[0118] In S1101, AP1(101) determines whether the STA that sent the Probe Request has the capability for Delayed Ack. For example, AP1(101) determines whether the STA has the capability for Delayed Ack based on the information contained in the received Probe Request. If the STA has the capability for Delayed Ack, proceed to S405. If not, proceed to S406.

[0119] In S405, AP1 (101) notifies AP2 (103) that STA (106) is the target of the capture. For example, this notification is made using the parameter 803 in Figure 8.

[0120] At S406, AP1(101) sends a Probe Response in response to the Probe Request received at S404. Subsequently, at S407, AP1(101) receives an Association Request.

[0121] Next, in S1102, AP1(101) checks if it has been instructed to capture the Coordinated AP. If it has, it proceeds to S409; otherwise, it proceeds to S411.

[0122] In S409, AP1(101) sends a confirmation signal to AP2(103) to check whether or not it has captured a frame from STA(106).

[0123] In S410, AP1(101) receives a capture acknowledgment from AP2(103) as a response to the acknowledgment signal transmitted in S409.

[0124] In S411, AP1(101) returns an Association Response to STA(106) as a response to the Association Request received in S407. In S1103, AP1(101) proceeds to S1104 if STA(106) has responded to the Delayed Ack and AP2(103) can capture the frame of the associated STA(106); otherwise, it proceeds to S1105.

[0125] In S1104, AP1(101) establishes a connection with STA(106). A configuration is set up here to execute Joint Receptio processing.

[0126] In S1105, AP1 (101) establishes a connection with STA (106). The configuration for executing Joint Reception processing is not set up here.

[0127] In S413, AP1(101) sends an ADDBA Request from STA(106). Then, in S415, AP1(101) returns an ADDBA Response frame to STA(106).

[0128] In S416, AP1(101) receives from STA(106) in A-MPDU format.

[0129] In S419, AP1(101) receives the BAR from STA(106).

[0130] In S1106, AP1(101) determines whether it was able to acquire all the A-MPDU data received from STA(106) in S416. If it was successful, it proceeds to S1107 and transmits BA to STA(106). If it was not possible to acquire all the data in S1106 due to radio interference or other reasons, it proceeds to S421.

[0131] In S421, AP1(101) notifies STA(106) that it has received the BAR by sending an Ack (normal Ack).

[0132] In S422, AP1(101) receives the A-MPDU payload captured from AP2(103).

[0133] In S423, AP1(101) organizes and integrates the A-MPDU data received in S416 and the data received in S422 in sequence number order.

[0134] In S424, AP1(101) generates a BA (Block Acknowledgment) based on the processing in S423 and sends it to STA(106). Then, in S425, AP1(101) receives an Ack from STA(106).

[0135] <Example 2> In Example 1, AP1(101) received all the data captured by AP2(103) at S422. In Example 2, we will describe an example in which, in order to reduce the amount of data communication, AP1(101) obtains only the data that it could not receive from STA(106) from AP2(103). Note that the basic configuration of this example is the same as in Example 1, so only the differences will be shown.

[0136] Figure 12 is a sequence diagram showing the processing in this embodiment. Since the basic configuration is the same as in Figure 4(b), only the differences are shown.

[0137] At timing 1201, which is between 416 and 419 in Example 1, AP1(101) transmits received data information, which is information about the data it has received, to AP2(103). This received data information is, for example, the sequence number of the MSDU in the A-MPDU received at 416.

[0138] Instead of processing 422 in Example 1, at 1202, AP2(103) forwards the missing data that AP1(101) could not receive to AP1(101) based on the received data information received at 1201.

[0139] This configuration has the effect of reducing the amount of data that AP2 transfers to AP1 compared to Example 1.

[0140] In this embodiment, AP1(101) was configured to send a normal Ack at 421, but AP1(101) may also be configured to send a BA for the amount of data received at 416. In this case, AP2(103) may detect the missing data by capturing the BA for the amount of data received. When AP1(101) is configured to send a BA instead of a normal Ack at 421, two BAs will be communicated for a single A-MPDU. Therefore, when implementing this configuration, settings for two-stage BA communication should be made in advance between AP1(101) and STA(106). For example, two-stage BA communication should be set in advance between AP1(101) and STA(106) during negotiation using the Delayed Ack capability of the UHR Capabilities element.

[0141] <Other Embodiments> A recording medium containing program code for software that implements the above-described functions may be supplied to a system or device, and the computer (CPU, MPU) of the system or device may read and execute the program code stored on the recording medium. In this case, the program code read from the storage medium itself implements the functions of the above-described embodiment, and the storage medium containing that program code constitutes the above-described device.

[0142] For storing program code, storage media such as flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, ROMs, and DVDs can be used.

[0143] Furthermore, the above-mentioned functions may be realized not only by the computer executing the program code it reads, but also by the operating system (OS) running on the computer performing some or all of the actual processing based on the instructions of that program code. OS stands for Operating System.

[0144] Furthermore, the program code read from the storage medium is written to the memory of a function expansion board inserted into the computer or a function expansion unit connected to the computer. Then, based on the instructions of that program code, the CPU of the function expansion board or function expansion unit may perform some or all of the actual processing to realize the above-mentioned functions.

[0145] The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0146] This embodiment includes the following configurations, methods, and programs.

[0147] (Composition 1) A communication device that communicates with a first other communication device and a second other communication device, A first execution means for configuring the first communication device to receive data in cooperation with the other communication device, A second execution means for setting a delay in transmitting BA (Block Ack) with the second other communication device, A first transmitting means that, upon receiving at least a portion of the first data transmitted from the second other communication device, transmits an Ack to the second other communication device, When the first other communication device receives at least a portion of the first data received by the first other communication device, a second transmission means transmits a BA to the second other communication device after the first transmission means transmits an Ack. A communication device characterized by having the following features.

[0148] (Configuration 2) The communication device according to configuration 1, characterized in that the first other communication device is an access point device and the second communication device is a station device.

[0149] (Composition 3) The first means for determining whether the aforementioned first other communication device is a communication device capable of performing data communication in cooperation with other communication devices further comprises a first determination means for determining whether the first other communication device is a communication device capable of performing data communication in cooperation with other communication devices. The communication device according to configuration 1 or 2, characterized in that when the first execution means determines that it is possible to perform data communication in cooperation with the first determination means, it sets up to receive data in cooperation with the first other communication device.

[0150] (Composition 4) The system further includes a second determination means for determining whether the second other communication device is a communication device capable of communicating BA with a delay, The communication device according to any one of configurations 1 to 3, characterized in that, when the second execution means determines that it is possible to communicate the BA with a delay, it makes a setting with the second other communication device to transmit the BA with a delay.

[0151] (Composition 5) A communication device according to any one of configurations 1 to 4, characterized in that the first other communication device and the second other communication device are not in a state of having established a communication connection.

[0152] (Composition 6) A communication device according to any one of configurations 1 to 5, characterized in that the communication device and the first other communication device are connected via a Distribution System (DS).

[0153] (Composition 7) A communication device according to any one of configurations 1 to 6, characterized in that, once the first execution means has performed the setup, the first other communication device receives a frame transmitted from the second other communication device and holds the frame for forwarding.

[0154] (Composition 8) A communication device according to any one of configurations 1 to 7, further comprising a second transmission means for transmitting a frame to the first other communication device for checking whether the first other communication device has received a frame transmitted from the second other communication device, when the first execution means has performed the setting.

[0155] (Composition 9) A communication device according to any one of configurations 1 to 8, further comprising integration means for integrating data transmitted from the second other communication device that has received at least a portion of the above, and data transmitted from the second other communication device that is received by the first other communication device.

[0156] (Composition 10) The communication device according to any one of configurations 1 to 9, characterized in that the setting for sending the aforementioned BA with a delay is the reception of an ADDBA Request and the transmission of an ADDBA Response.

[0157] (Composition 11) A communication device according to any one of configurations 1 to 10, characterized in that it uses a Delayed Block Ack compliant with the IEEE 802.11 series standard in order to transmit the aforementioned BA with a delay.

[0158] (Composition 12) The communication device according to any one of configurations 1 to 11, characterized in that the communication with the second other communication device is compliant with the IEEE 802.11 series standard.

[0159] (Composition 13) A communication device that communicates with a first other communication device and a second other communication device, A first execution means for configuring the first communication device to receive data in cooperation with the other communication device, A second execution means for setting a delay in transmitting BA (Block Ack) with the second other communication device, A first transmitting means that, upon receiving at least a portion of the first data transmitted from the second other communication device, transmits the first BA to the second other communication device, When the first other communication device receives at least a portion of the first data received by the first other communication device, a second transmitting means transmits a second BA to the second other communication device after the first BA transmission by the first transmitting means, A communication device characterized by having the following features.

[0160] (method) A control method performed by a communication device that communicates with a first other communication device and a second other communication device, A first execution step involves setting up the device to receive data in cooperation with the aforementioned first other communication device, A second execution step involves setting up the second communication device to send BA (Block Ack) with a delay, A first transmission step in which, upon receiving at least a portion of the first data transmitted from the second other communication device, an Ack is sent to the second other communication device, When the first other communication device receives at least a portion of the first data received by the first other communication device, a second transmission step is to transmit a BA to the second other communication device after the Ack transmission by the first transmission means, A control method characterized by having the following features.

[0161] (program) A program for operating a computer as one of the means of a communication device described in any one of items 1 to 13. [Explanation of Symbols]

[0162] 101 AP1 103 AP2 105 DS 106 STA 617 HT-delayed Block Acknowledgment 905 Block Acknowledgment Policy

Claims

1. A communication device that communicates with a first other communication device and a second other communication device, A first execution means for configuring the first communication device to receive data in cooperation with the other communication device, A second execution means for setting a delay in transmitting BA (Block Ack) with the second other communication device, A first transmitting means that, upon receiving at least a portion of the first data transmitted from the second other communication device, transmits an Ack to the second other communication device, When the first other communication device receives at least a portion of the first data received by the first other communication device, a second transmission means transmits BA to the second other communication device after the Ack transmission by the first transmission means, A communication device characterized by having the following features.

2. The communication device according to claim 1, characterized in that the first other communication device is an access point device and the second communication device is a station device.

3. The first means for determining whether the aforementioned first other communication device is a communication device capable of performing data communication in cooperation with other communication devices further comprises a first determination means for determining whether the first other communication device is a communication device capable of performing data communication in cooperation with other communication devices. The communication device according to claim 1, characterized in that when the first execution means determines that it is possible to perform data communication in cooperation with the first determination means, it sets up to receive data in cooperation with the first other communication device.

4. The system further includes a second determination means for determining whether the second other communication device is a communication device capable of communicating BA with a delay, The communication device according to claim 1, characterized in that, when the second execution means determines that it is possible to communicate the BA with a delay, it makes a setting with the second other communication device to transmit the BA with a delay.

5. The communication device according to claim 1, characterized in that the first other communication device and the second other communication device are not in a state of having established a communication connection.

6. The communication device according to claim 1, characterized in that the communication device and the first other communication device are connected via a DS (Distribution System).

7. The communication device according to claim 1, wherein, once the first execution means has performed the setting, the first other communication device receives a frame transmitted from the second other communication device and holds the frame for forwarding.

8. The communication device according to claim 1, further comprising a second transmission means for transmitting a frame to the first other communication device for checking whether the first other communication device has received a frame transmitted from the second other communication device, when the first execution means has performed the setting.

9. The communication device according to claim 1, further comprising integration means for integrating data transmitted from the second other communication device that has received at least a portion of the above, and data transmitted from the second other communication device that is received by the first other communication device.

10. The communication device according to claim 1, characterized in that the setting for sending the BA with a delay is the reception of an ADDBA Request and the transmission of an ADDBA Response.

11. The communication device according to claim 1, characterized in that it uses a Delayed Block Ack compliant with the IEEE 802.11 series standard to transmit the aforementioned BA with a delay.

12. The communication device according to claim 1, characterized in that the communication with the second other communication device is in accordance with the IEEE 802.11 series standard.

13. A communication device that communicates with a first other communication device and a second other communication device, A first execution means for configuring the first communication device to receive data in cooperation with the other communication device, A second execution means for setting a delay in transmitting BA (Block Ack) with the second other communication device, A first transmitting means that, upon receiving at least a portion of the first data transmitted from the second other communication device, transmits the first BA to the second other communication device, When the first other communication device receives at least a portion of the first data received by the first other communication device, a second transmitting means transmits a second BA to the second other communication device after the first BA transmission by the first transmitting means, A communication device characterized by having the following features.

14. A control method performed by a communication device that communicates with a first other communication device and a second other communication device, A first execution step involves setting up the device to receive data in cooperation with the aforementioned first other communication device, A second execution step involves setting a second communication device to send a BA (Block Ack) with a delay, A first transmission step in which, upon receiving at least a portion of the first data transmitted from the second other communication device, an Ack is transmitted to the second other communication device, When the first other communication device receives at least a portion of the first data received by the first other communication device, a second transmission step is to transmit BA to the second other communication device after the Ack transmission by the first transmission means, A control method characterized by having the following features.

15. A program for causing a computer to operate as one of the means of a communication device described in any one of claims 1 to 13.

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