Communication device, control method, and program product

Abstract

A communication device, control method, and storage medium are disclosed. When a connection is established between the communication device 100 and a first other communication device 102, but no connection is established between the communication device 100 and second other communication devices 101 and 103, first information shared by the first other communication device 102 and the second other communication devices 101 and 103 regarding the second other communication devices 101 and 103 is received. If the received first information includes a first field included in a received predetermined frame and indicating the source of the predetermined frame, data fields following the first field of the predetermined frame are read.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a communication device that performs wireless communication. BACKGROUND

[0002] The IEEE 802.11 series of standards is referred to as a wireless LAN (Local Area Network) communication standard. IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers, and the IEEE 802.11 series of standards includes IEEE 802.11a / b / g / n / ac / ax standards and the like.

[0003] In IEEE 802.11ax described in PTL 1, in addition to achieving a high peak throughput, a standard that allows improving a communication speed under a congested condition is included. As a successor standard of IEEE 802.11ax, IEEE 802.11be (hereinafter referred to as 11be) is being developed.

[0004] In 11be, a technology that allows multiple APs (Access Points) to cooperate with each other when performing data communication with STAs (Stations) to achieve an improved throughput is being studied.

[0005] LIST OF CITATIONS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Laid-Open No. 2018-50133 SUMMARY

[0008] TECHNICAL PROBLEM

[0009] A frame transmitted by an AP in wireless communication includes a field that contains information indicating a transmission source. According to a conventional technology, based on the information included in the field and information about an AP with which a connection has been established by a STA, the STA determines whether or not to read information after the field.

[0010] However, in multi-AP communication planned to be supported by 11be, multiple APs participate in communication, but the APs do not establish connections with all STAs participating in the communication, and there is a possibility that a STA receives a frame from an AP with which a connection has not been established.

[0011] In this case, the frame includes information about the AP with which a connection has not been established as the information of the transmission source in the field, which can cause the STA not to read information after the above field, and thus the STA not to read a data field included in the frame.

[0012] In view of the above, an object of the present application is to enable a communication device to read a data field of a frame to be read even when the frame is transmitted from a device with which a connection has not been established.

[0013] Solution to the problem

[0014] To achieve the above object, in one aspect of the present application, a communication apparatus includes: a reception unit configured to receive a first predetermined frame transmitted from a first other communication apparatus to the communication apparatus, the first predetermined frame including, in a data field, first information about a second other communication apparatus shared between the first other communication apparatus and the second other communication apparatus, wherein the first other communication apparatus has established a connection with the communication apparatus, and the second other communication apparatus has not established a connection with the communication apparatus; and a reading unit configured to read, in a case where the reception unit receives a second predetermined frame whose transmission source is a communication apparatus different from the first other communication apparatus, and a value of a first field included in the second predetermined frame and indicating the transmission source of the second predetermined frame matches the first information shared by the first other communication apparatus as a result of the communication apparatus receiving the first predetermined frame, a data field included in the second predetermined frame after the first field.

[0015] Effects of the Invention

[0016] According to the present application, even when a frame is transmitted from an apparatus that has not established a connection, the communication apparatus can read a data field of a frame to be read. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a diagram showing a configuration of a network to which a communication apparatus 100 belongs.

[0018] Figure 2 is a diagram showing a hardware structure of the communication apparatus 100 to the communication apparatus 103.

[0019] Figure 3 is a diagram showing a frame format of a MAC frame.

[0020] Figure 4 is a diagram showing a PPDU according to the IEEE 802.11be standard.

[0021] Figure 5 is a sequence diagram showing a process of reading information after a field containing information of a transmission source of a frame transmitted by an AP that has not established a connection.

[0022] Figure 6 is a flowchart showing a process performed by the communication apparatus 100. DETAILED DESCRIPTION

[0023] Embodiments of the present application are described in detail below with reference to the accompanying drawings. Note that the following described embodiments are provided by way of example only, and the scope of the present application is not limited to these embodiments.

[0024] Figure 1 The configuration of a network in which communication device 100 participates according to an embodiment is shown. Communication device 100 is a station (STA) capable of communicating with communication device 102 and responsible for participating in wireless network 105. Communication device 101 is an access point (hereinafter referred to as AP) that has the function of building wireless network 104, communication device 102 is an AP that builds wireless network 105, and communication device 103 is an AP that builds wireless network 106. In this embodiment, communication device 101 is used as a shared AP that manages other APs, and communication devices 102 and 103 are shared APs that operate under the management of a master AP. An example of multi-AP communication with multiple APs is distributed MIMO technology based on MIMO (Multiple-Input Multiple-Output) technology, which uses multiple transmit and receive antennas simultaneously on the same channel. In distributed MIMO, in an environment with multiple APs and multiple STAs, information about the communication status and information about the status of each AP are shared by multiple APs, and data is transmitted from APs to STAs at the same timing. By performing cooperation among multiple APs in the manner described above, the number of spatial streams can be increased compared to the case where communication is performed by a single AP, and thus throughput can be improved. Each of communication devices 100 to 103 is capable of performing wireless communication according to the IEEE 802.11be standard. Note that IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers. Communication devices 100 to 103 can communicate in the frequency bands of 2.4 GHz, 5 GHz, and 6 GHz. During communication, communication devices 100 to 103 can use bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, and 320 MHz.

[0025] By implementing OFDMA communication according to the IEEE 802.11be standard, communication devices 100 to 103 can achieve multi-user (MU) communication, where the signals of multiple users are multiplexed. OFDMA stands for Orthogonal Frequency Division Multiple Access. In OFDMA communication, a portion of the frequency band (RU, resource element) is allocated to each STA, ensuring no overlap and that the carriers of each STA are orthogonal. This allows the AP to communicate in parallel with multiple STAs.

[0026] The above assumes that communication devices 100 to 103 support the IEEE 802.11be standard. Note that, in addition to or replacing the IEEE 802.11be standard, communication devices 100 to 103 may support legacy standards prior to IEEE 802.11be. More specifically, communication devices 100 to 103 may support at least one of the IEEE 802.11a / b / g / n / ac / ax standards and subsequent standards. Besides the IEEE 802.11 standard family, other communication standards may also be supported, such as Bluetooth (registered trademark), NFC, UWB, ZigBee, and MBOA. UWB is an abbreviation for Ultra Wideband, and MBOA is an abbreviation for Multi-Band OFDM Consortium. NFC is an abbreviation for Near Field Communication. UWB includes Wireless USB, Wireless 1394, WiNET, etc. Furthermore, wired communication standards such as wired LAN may be supported.

[0027] Specific examples of communication devices 100 to 103 include, but are not limited to, wireless LAN routers, personal computers (PCs), etc. Specific examples of communication device 100 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, video cameras, etc. Although Figure 1 The wireless network shown includes three access points (APs) and one STA, but the number of APs and STAs is not limited to this.

[0028] Figure 2 An example of the hardware configuration of the communication device 101 according to this embodiment is shown. The communication device 101 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 communication devices 100, 102, and 103 also each have a hardware configuration similar to that of the communication device 101.

[0029] Storage unit 201 is implemented using a memory such as ROM or RAM, and is used to store computer programs for performing various operations described later, as well as various information such as communication parameters for wireless communication. ROM is an abbreviation for Read-Only Memory, and RAM is an abbreviation for Random Access Memory. In addition to memories such as ROM and RAM, 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 also be used as storage unit 201. Storage unit 201 may include multiple memories, etc.

[0030] Control unit 202 includes one or more processors such as a CPU and an MPU, and controls the entire communication device 101 by executing a computer program stored in storage unit 201. CPU is an abbreviation for Central Processing Unit, and MPU is an abbreviation for Microprocessor. Note that control unit 202 can control the entire communication device 101 through cooperation between the computer program stored in storage unit 201 and the OS (operating system). Control unit 202 also generates data and signals to be transmitted in communication with another communication device. Control unit 202 may include multiple processors such as a multi-core processor, and the entire communication device 101 can be controlled by multiple processors. Control unit 202 also controls functional unit 203 to perform specific processes such as wireless communication, imaging, printing, projection, etc. Functional unit 203 is the hardware that performs specific processes on communication device 101.

[0031] Input unit 204 receives various operations from the user. Output unit 205 provides various outputs to the user via a monitor screen or speaker. Here, the output from output unit 205 can be information displayed on the monitor screen, audio information output from the speaker, vibration, etc. Note that both input unit 204 and output unit 205 can be implemented in a single module such as a touch panel. Input unit 204 and output unit 205 can be integrated with communication device 101, or they can be provided separately from communication device 101.

[0032] Communication unit 206 controls wireless communication according to the IEEE 802.11be standard. In addition to the IEEE 802.11be standard, communication unit 206 can control wireless communication according to other IEEE 802.11 standard families, and / or can control wired communication such as wired LAN. Through control antenna 207, communication unit 206 transmits and receives wireless signals generated by control unit 202 for wireless communication.

[0033] Note that when communication device 101 supports standards such as NFC and Bluetooth, it can control wireless communication according to these standards, in addition to the IEEE 802.11be standard. When communication device 101 can perform wireless communication according to multiple standards, a communication unit 206 and an antenna 207 can be provided for each standard. Communication device 101 communicates data such as image data, document data, and video data with communication device 100 via communication unit 206.

[0034] Figure 3The frame format of a MAC frame is shown. This conforms to the format specified in the IEEE 802.11 series. That is, it includes, from the beginning, a frame control field 301, a duration field 302, an RA field 303, and a TA field 304. Here, RA in RA field 303 is an abbreviation for the receiver address, and TA in TA field 304 is an abbreviation for the sender address. RA field 303 indicates information about the destination of the frame, and TA field 304 indicates information about the source of the data frame. In this embodiment, the data field of the frame is read when the information in TA field 304 matches the MAC address of the AP participating in multi-AP communication, as described later.

[0035] Figure 4 The diagram illustrates a PPDU (Physical Layer (PHY) Protocol Data Unit) according to the IEEE 802.11be standard. Its frame start portion includes L (Legacy)-STF 401, L-LTF 402, and L-SIG 403, which are backward compatible with the IEEE 802.11a / b / g / n / ax standards. L-STF 401 is used for detecting PHY frame signals, performing Automatic Gain Control (AGC), and timing detection. Following L-STF 401, L-LTF 402 is used for high-precision frequency / time synchronization and acquiring Channel State Information (CSI). L-SIG 403, following L-LTF 402, is used to transmit control information, including information about the data transmission rate and PHY frame length. Traditional devices conforming to the IEEE 802.11a / b / g / n / ax standard can decode the data in the aforementioned traditional fields (L-STF 401, L-LTF 402, L-SIG 403). Following these traditional fields are the fields RL-SIG 404, EHT-SIG-A 405, EHT-SIG B 406, EHT-STF 407, EHT-LTF 408, data field 409, and packet extension 410. EHT stands for Extremely High Throughput. EHT-SIG-A 405 contains information such as EHT-SIG-A1 and EHT-SIG-A2 required for receiving PPDUs. The subfields contained in EHT-SIG-A1 and EHT-SIG-A2 within EHT-SIG-A5 and their descriptions are shown in Tables 1 and 2, respectively.

[0036] Table 1

[0037]

[0038]

[0039]

[0040] Table 2

[0041]

[0042]

[0043] EHT-SIG-B 406 contains information such as general fields and user block fields required to receive PPDUs.

[0044] EHT-STF 407, following EHT-SIG-B 406, is an abbreviation for the EHT Short Training Field, whose main purpose is to improve automatic gain control in MIMO transmission. EHT-LTF 408 is an abbreviation for the EHT Long Training Field and provides the receiver with means for estimating the MIMO channel. Data field 409 may contain data from MIMO communication transmitted with the NSTS and SS (spatial stream) number indicated in the intermediate period subfield of EHT-SIG-A1. In this embodiment, the data field is read when the BSS color information included in the EHT-SIG-A field 405 matches the BSS color information used to distinguish the network constructed by APs participating in the multi-AP communication described later.

[0045] Figure 5 A sequence diagram is shown of a communication device 100 reading a data field from a frame sent from an AP with which it has not yet established a connection. In this embodiment, the data field is read when a field containing information indicating the source of a frame sent from an AP with which the communication device 100 has not established a connection contains information about one of the APs participating in multi-AP communication.

[0046] In S501, communication devices 101 to 103, operating as APs, perform connection to STAs according to the IEEE 802.11 series of standards. Specifically, they send and receive probe requests / responses, association requests / responses, and authentication requests / responses with the STAs, respectively. Communication devices 101 to 103 establish wireless links by sending and receiving these frames from each STA. Here, communication device 101, acting as a shared AP, establishes a connection with STA_01; communication device 102, acting as a shared AP, establishes connections with communication devices 100 and STA_12; and communication device 103, acting as a shared access point, establishes a connection with STA_21. In S502, a multi-AP communication system setup is performed. Communication device 101, acting as a shared AP in the multi-AP communication system setup, sends trigger frames to communication devices 102 and 103. When communication devices 102 and 103 receive the trigger frames, they send response frames to communication device 101. The trigger frame is the frame in which communication device 101 allocates RUs to each of communication devices 102 and 103, and prompts communication devices 102 and 103 to send specified information to communication device 101 using the allocated RUs. The response frame includes identification information of the STAs that have established connections with communication devices 102 and 103, the MAC addresses of communication devices 102 and 103, and information about the network constructed by communication devices 102 and 103. The identification information of each STA includes its MAC address, IP address, etc. The information about the network constructed by communication devices 102 and 103 includes SSID and / or BSSID, BSS color, etc. Here, BSS is an abbreviation for Basic Service Set. Therefore, communication device 101, acting as a shared AP, collects information about the APs participating in multi-AP communication by receiving the response frame. In S502, communication device 101 determines whether communication devices 102 and 103 want to participate in multi-AP communication based on the information in the response frames sent by communication devices 102 and 103. Then, the communication device 101, acting as a shared AP, sends the information about the APs participating in the multi-AP communication collected in S502 to the communication devices 102 and 103, which have already been identified as participating in the multi-AP communication. This allows the communication devices 102 and 103, acting as a shared AP, to obtain information about the APs participating in the multi-AP communication. Here, the information about each AP participating in the multi-AP communication includes, but is not limited to, the AP's MAC address as AP identification information, the BSS color as information used to distinguish the network constructed by the APs, etc.

[0047] Communication device 101 sends information about the APs participating in the multi-AP communication, shared in S502, to the STAs (S503). Information about each AP participating in the multi-AP communication is also sent from the participating APs to each STA with which a connection has been established in S501. This information about the participating APs is sent from communication device 101 to STA_01, from communication device 102 to communication devices 100 and STA_12, and from communication device 103 to STA_21. This allows the STAs to know information about the APs participating in the multi-AP communication.

[0048] Communication device 101 sends a frame to communication device 100, which is a STA that has not yet established a connection (S504). Here, regarding the frame type, the frame can be a management frame, a control frame, or a data frame. Before sending the frame, communication device 101 can perform probing with each AP and each STA to collect CSI between the APs and STAs, thereby understanding the status of the destination communication device, and then communication device 101 can send the frame. Instead of CSI, communication device 101 can understand the status of the destination communication device based on information received in S502 regarding STAs that have already established connections with communication devices 102 and 103. Communication device 100 determines whether to read the frame based on information shared in S503 about the APs participating in multi-AP communication and the source information included in the frame sent by communication device 101 (S505). See below for further details. Figure 6 Describe the detailed process in S505.

[0049] Figure 6 This is a flowchart illustrating the process performed by the control unit 202 by executing a program stored in the storage unit 201 of the communication device 100. More specifically, the flowchart illustrates the process of reading data fields contained in a frame sent by the communication device 101 before a connection with the communication device 100 has been established, wherein the data fields follow fields containing information about the source of the frame's transmission.

[0050] When communication device 100 detects the start of a frame sent by communication device 101, it begins flowchart processing. In this embodiment, flowchart processing begins in response to the detection of L-STF at the beginning of a frame, but this is only an example, and the beginning of a frame is not limited to L-STF.

[0051] First, in S601, it is determined whether the detected frame type conforms to IEEE 802.11be. This type is determined based on the modulation method and various parameters explained in the physical header portion of the detected frame. If it is determined in S601 that the frame type does not conform to IEEE 802.11be, it is further determined whether the frame destination information included in the RA field of the frame matches the identification information of the communication device 100 (S604). Here, the identification information of the communication device 100 includes, but is not limited to, a MAC address or a broadcast address. If it is determined to be positive in S604, it is further determined in S605 whether the information in the TA field of the sending source communication device matches the MAC address of the AP that has established a connection with the communication device 100. If it is determined to be positive in S605, the communication device 100 reads the information described after the TA field in the frame sent by the communication device 101 (S606). If it is determined to be negative in S604 or S605, the communication device 100 does not read the information described after the TA field in the frame sent by the communication device 101 (S607).

[0052] If, in S601, it is determined that the frame type conforms to IEEE 802.11be, in S602, it is further determined whether the frame destination information included in the RA field of the frame matches the identification information of the communication device 100. Here, the identification information of the communication device 100 includes, but is not limited to, a MAC address or a broadcast address. If it is determined to be positive in S602, it is further determined whether the information in the TA field contained in the sending source communication device matches the information shared in S503 regarding one of the APs participating in the multi-AP communication. More specifically, it is determined whether the information about the sending source of the communication contained in the TA field of the frame sent by the communication device 101 matches the MAC address of one of the APs participating in the multi-AP communication shared in S503. If it is determined to be positive in S603, the communication device 100 reads the information described after the TA field in the frame sent by the communication device 101 (S606). If it is determined to be negative in S602 or S603, the communication device 100 does not read the data field after the TA field in the frame sent by the communication device 101 (S607).

[0053] In this embodiment, as an example, it is assumed that the MAC address is used as information about the APs participating in multi-AP communication; however, alternatively, BSS colors can be used. When using BSS colors, it is determined whether the BSS color in the EHT-SIGA of the frame matches the BSS color of the network constructed by one of the APs participating in the shared multi-AP communication in S503.

[0054] Note that S601 can be omitted. In this case, Figure 6 The processing in the flowchart shown starts from S602.

[0055] According to this embodiment, the communication device 100 can read a data field located after a field containing information indicating the source of a frame sent from another communication device with which a connection has not yet been established.

[0056] According to the above embodiments, as an example, assume that there are Figure 2 The communication device with the hardware configuration shown performs... Figure 6 The flowchart shown illustrates the processing, but... Figure 6 The flowchart processing can be comprised of, among other things. Figure 2 The wireless chip executing the storage unit, control unit, and communication unit shown is used in this embodiment. In other words, the communication device may include... Figure 2 The wireless chip shown includes the storage unit, control unit, and communication unit.

[0057] The software program code used to implement the above functions can be stored in a storage medium, and this storage medium can be provided to a system or device, and the computer (CPU, MPU) of the system or device can read and execute the software program stored in the storage medium. In this case, the program code read from the storage medium implements the functions of the above embodiments, and the program code constitutes the storage medium of the above-described device.

[0058] Examples of storage media used to provide program code include floppy disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, ROMs, DVDs, etc.

[0059] Besides reading and executing program code to achieve the above functions, these functions can also be achieved through an OS, on which the computer runs by executing some or all of the actual processing according to the instructions in the program code. OS is an abbreviation for Operating System.

[0060] Furthermore, the above-mentioned functions can be implemented such that program code is loaded from the storage medium into a memory located on a function expansion board inserted into the computer or in a function expansion unit connected to the computer, and part or all of the actual processing can be executed by the CPU located on the function expansion card or function expansion unit according to the instructions of the loaded program code.

[0061] The present invention can also be implemented by providing a program for implementing one or more functions of this embodiment to a system or device via a network or storage medium, and having the program read and executed by one or more processors in a computer located in the system or device. The present invention can also be implemented by a circuit (e.g., an ASIC) that implements one or more functions.

[0062] This invention is not limited to the embodiments described above, but various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the following claims are appended to disclose the scope of the invention.

[0063] This application claims priority to Japanese Patent Application No. 2020-162160, filed on September 28, 2020, the entire contents of which are incorporated herein by reference.

Claims

1. A communication device that performs multi-access point (AP) communication with a first other communication device operating as an access point and a second other communication device operating as an access point, the communication device comprising: The connection unit is configured to establish a connection with the first other communication device by performing a predetermined connection process; The receiving unit is configured to receive first information from the first other communication device relating to one or more access points joining the multi-AP communication, and to receive wireless communication frames from the second other communication device, wherein the first other communication device has already established a connection with the communication device, and the second other communication device has not yet performed the predetermined connection process with the communication device. as well as The reading unit is configured to read a data field following a first field containing the transmitter information if the receiver information included in the wireless communication frame indicates the communication device and the transmitter information included in the wireless communication frame corresponds to one of the one or more access points joining the multi-AP communication, and not to read the data field following the first field if the transmitter information included in the first field does not correspond to any of the one or more access points joining the multi-AP communication.

2. The communication apparatus of claim 1, further comprising a determining unit configured to determine whether the first information received by the receiving unit is included in a first field indicating transmitter information of the wireless communication frame.

3. The communication device according to claim 1, wherein, The receiver information is the MAC address or broadcast address of the device to which the wireless communication frame is destined.

4. The communication device according to claim 1, wherein the receiver information is included in the RA (Receiver Address) field.

5. The communication device according to claim 1, wherein, The wireless communication frame is a frame according to the IEEE 802.11 standard series.

6. The communication device according to claim 1, wherein, The first information is the MAC address of the second other communication device or the BSS (Basic Service Set) color used to distinguish the wireless network constructed by the second other communication device.

7. The communication device according to claim 1, wherein, The first field is either the TA (sender address) field or the EHT (Extremely High Throughput)-SIG-A field, which includes the BSS color subfield.

8. The communication device according to claim 1, wherein, The first other communication device and the second other communication device each operate as an AP according to the IEEE 802.11 standard series.

9. A communication method for a communication device, the communication device performing multi-access point (AP) communication with a first other communication device operating as an access point and a second other communication device operating as an access point, the communication method comprising: A connection is established with the first other communication device by performing a predetermined connection process; Receive first information related to one or more access points joining the multi-AP communication from the first other communication device, and receive wireless communication frames from the second other communication device, wherein the first other communication device has already established a connection with the communication device, and the second other communication device has not yet performed the predetermined connection process with the communication device; as well as If the receiver information included in the wireless communication frame indicates the communication device and the transmitter information included in the wireless communication frame corresponds to one of the one or more access points joining the multi-AP communication, the data field following the first field including the transmitter information is read; if the transmitter information included in the first field does not correspond to any of the one or more access points joining the multi-AP communication, the data field following the first field is not read.

10. A program product comprising a program configured to cause a computer to function as a unit of a communication device according to any one of claims 1-8.

Images