Communication device, communication method, and program

Abstract

To provide a communication device that can read a data field in a frame that should be read even when the frame is transmitted from a device with which no connection is established.SOLUTION: A communication device 100: receives first information shared between a first communication device 102 that has established a connection with the communication device 100 and second communication devices 101, 103 that have not established a connection with the communication device 100 and regarding the second communication devices 101, 103 (S503); in response to receiving a predetermined frame (S504), determines whether or not the received first information is contained in a first field indicating a transmission source of the predetermined frame (S505); and in response to determining that the first information is contained, reads data fields following the first field in the predetermined frame.SELECTED DRAWING: Figure 5

Description

Technical Field

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

Background Art

[0002] As communication standards for wireless LAN (Local Area Network), the IEEE802.11 standard series is known. IEEE is an abbreviation for Institute of Electrical and Electronics Engineers, and the IEEE802.11 standard series includes standards such as IEEE802.11a / b / g / n / ac / ax, etc.

[0003] In IEEE802.11ax described in Patent Document 1, in addition to high peak throughput, a technique for improving the communication speed under congested conditions has been standardized. And as a successor standard to IEEE802.11ax, the standardization of IEEE802.11be (hereinafter 11be) is being carried out.

[0004] In 11be, a technique is being studied in which a plurality of APs (Access Points) perform cooperative operations and perform data communication with a STA (Station) to improve throughput.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In wireless communication, frames transmitted by an access point (AP) contain a field that includes information indicating the source. Conventional STAs (Stand-Assisted Devices) determined whether or not to read the information after that field based on the information contained in the field and the information of the AP with which the device had established a connection.

[0007] However, in Multi-AP communication, which is being considered for introduction in 11be, multiple APs participate in the communication, but each AP does not establish a connection with all STAs participating in the communication, and an STA may receive frames from APs with which it has not established a connection. In this case, the frame contains information about APs with which it has not established a connection as source information included in the above fields, so the STA may not read the information after that field, and the data fields included in the frame may not be read.

[0008] Therefore, the present invention aims to enable a communication device to read the data field of a frame that should have its data field read, even if the frame was transmitted from a device that has not established a connection. [Means for solving the problem]

[0009] To achieve the above objective, a communication device according to one aspect of the present invention is: Receiving means for receiving first information relating to the second other communication device, which is shared between a first other communication device that has established a connection with the aforementioned communication device and a second other communication device that has not established a connection with the aforementioned communication device. When a predetermined frame is received, a determination means determines whether the first information received by the receiving means is included in the first field, which is contained in the predetermined frame and indicates the source of the predetermined frame. If the determination means determines that the first information is included, the reading means reads the data fields included in the predetermined frame from the first field onward, It has. [Effects of the Invention]

[0010] According to the present invention, a communication device can read the data field of a frame whose data field should be read, even if the frame was transmitted from a device with which a connection has not been established. [Brief explanation of the drawing]

[0011] [Figure 1] This diagram shows the network configuration to which the communication device 100 belongs. [Figure 2] This diagram shows the hardware configuration of communication devices 100 to 103. [Figure 3] This diagram shows the frame format of a MAC frame. [Figure 4] This diagram shows a PPDU compliant with the IEEE 802.11be standard. [Figure 5] This sequence diagram shows the process of reading from the field containing the source information of a frame sent by an AP that has not yet established a connection. [Figure 6] This is a flowchart showing the processes performed by the communication device 100. [Modes for carrying out the invention]

[0012] Embodiments of the present invention will be described in detail below with reference to the attached drawings. Note that the configurations shown in the following embodiments are merely examples, and the present invention is not limited to the illustrated configurations.

[0013] Figure 1 shows the network configuration in which the communication device 100 according to this embodiment participates. The communication device 100 is a station (STA) that can communicate with the communication device 102 and has the role of participating in the wireless network 105. The communication device 101 is an access point (AP) that has the role of constructing the wireless network 104, the communication device 102 is an AP that constructs the wireless network 105, and the communication device 103 is an AP that constructs the wireless network 106. In this embodiment, the communication device 101 functions as a Sharing AP that manages other APs, and the communication devices 102 to 103 are Shared APs that operate under the management of the master AP. As an example of Multi-AP communication in which multiple APs operate, distributed MIMO technology based on MIMO (Multi-Input Multi-Output) technology that uses multiple transmitting and receiving antennas simultaneously on the same channel can be cited. In distributed MIMO, in an environment in which multiple APs and multiple STAs exist, information about the communication status and the status of each AP is shared among the multiple APs, and data is sent from the APs to the STAs at the same time. By having multiple APs work together in this way, the number of spatial streams can be increased compared to when a single AP communicates, and thus an improvement in throughput can be expected. Each of the communication devices 100 to 103 can perform wireless communication in accordance with the IEEE 802.11be standard. IEEE stands for Institute of Electrical and Electronics Engineers. Communication devices 100 to 103 can communicate in the 2.4GHz, 5GHz, and 6GHz frequency bands. In addition, communication devices 100 to 103 can communicate using bandwidths of 20MHz, 40MHz, 80MHz, 160MHz, and 320MHz.

[0014] Communication devices 100-103 can implement multi-user (MU) communication by multiplexing signals from multiple users by performing OFDMA communication compliant with the IEEE 802.11be standard. OFDMA stands for Orthogonal Frequency Division Multiple Access. In OFDMA communication, a portion of the divided frequency band (RU, Resource Unit) is allocated to each STA so as not to overlap, and the carrier waves of each STA are orthogonal. Therefore, an AP can communicate with multiple STAs in parallel.

[0015] Although communication devices 100-103 are stated to be compliant with the IEEE 802.11be standard, they may also be compliant with legacy standards that precede the IEEE 802.11be standard, either in addition to or instead of this. Specifically, communication devices 100-103 may be compliant with at least one of the IEEE 802.11a / b / g / n / ac / ax standards and their successors. In addition to the IEEE 802.11 standard series, they may also be compliant with other communication standards such as Bluetooth®, NFC, UWB, ZigBee, and MBOA. UWB stands for Ultra Wide Band, and MBOA stands for Multi Band OFDM Alliance. NFC stands for Near Field Communication. UWB includes wireless USB, wireless 1394, and WiNET. They may also be compliant with wired communication standards such as wired LAN.

[0016] Specific examples of communication devices 100-103 include, but are not limited to, wireless LAN routers and personal computers (PCs). Similarly, specific examples of communication device 100 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, and video cameras. Furthermore, while the wireless network in Figure 1 consists of three APs and one STA, the number of APs and STAs is not limited to these.

[0017] Figure 2 shows an example of the hardware configuration of the communication device 101 according to the present embodiment. 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 the communication devices 100, 102, and 103 also have the same hardware configuration as the communication device 101.

[0018] The storage unit 201 is composed of a memory such as a ROM or a RAM, and stores computer programs for performing various operations described later, and 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. Note that, as the storage unit 201, in addition to memories such as ROM and RAM, storage media such as flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, and DVDs may be used. Further, the storage unit 201 may include a plurality of memories or the like.

[0019] The control unit 202 is composed of one or more processors such as a CPU or an MPU, and controls the entire communication device 101 by executing the computer program stored in the storage unit 201. CPU is an abbreviation for Central Processing Unit, and MPU is an abbreviation for Micro Processing Unit. Note that the control unit 202 may control the entire communication device 101 in cooperation with the computer program stored in the storage unit 201 and the OS (Operating System). Further, the control unit 202 generates data and signals to be transmitted in communication with other communication devices. Further, the control unit 202 may include a plurality of processors such as a multi-core, and control the entire communication device 101 by the plurality of processors. Further, the control unit 202 controls the functional unit 203 to execute predetermined processes such as wireless communication, imaging, printing, and projection. The functional unit 203 is hardware for the communication device 101 to execute predetermined processes.

[0020] The input unit 204 receives various operations from the user. The output unit 205 provides various outputs to the user via a monitor screen or speaker. Here, the output from the output unit 205 may be a display on the monitor screen, audio output via a speaker, vibration output, etc. The input unit 204 and the output unit 205 may also be implemented in a single module, such as a touch panel. Furthermore, the input unit 204 and the output unit 205 may be integrated with the communication device 101 or may be separate components.

[0021] The communication unit 206 controls wireless communication in accordance with the IEEE 802.11be standard. In addition to the IEEE 802.11be standard, the communication unit 206 may also control wireless communication in accordance with other IEEE 802.11 standard series, or control wired communication such as wired LAN. The communication unit 206 controls the antenna 207 to transmit and receive wireless signals for wireless communication generated by the control unit 202.

[0022] Furthermore, if the communication device 101 supports NFC, Bluetooth, or other standards in addition to the IEEE 802.11be standard, it may control wireless communication compliant with these communication standards. Also, if the communication device 101 can perform wireless communication compliant with multiple communication standards, it may be configured to have separate communication units 206 and antennas 207 corresponding to each communication standard. The communication device 101 communicates data such as image data, document data, and video data with the communication device 100 via the communication unit 206.

[0023] Figure 3 shows the frame format of a MAC frame. It conforms to the format specified in the IEEE 802.11 series. That is, it includes the Frame Control field 301, Duration field 302, RA field 303, and TA field 304 from the beginning. Here, RA field 303 is an abbreviation for Receiver Address, and TA field 304 is an abbreviation for Transmitter Address. RA field 303 indicates the destination information of the frame, and TA field 304 indicates the source information 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 an AP participating in the Multi-AP communication described later.

[0024] Figure 4 shows a PPDU (Physical Layer (PHY) Protocol Data Unit) compliant with the IEEE 802.11be standard. The beginning of the frame contains L(Legacy)-STF401, L-LTF402, and L-SIG403, which are backward compatible with the IEEE 802.11a / b / g / n / ax standards. L-STF401 is used for detecting the PHY frame signal, automatic gain control (AGC), and timing detection. L-LTF402, located immediately after L-STF701, is used for high-precision frequency and time synchronization and acquisition of propagation channel information (CSI). Here, CSI stands for Channel State Information. L-SIG403, located immediately after L-LTF402, is used to transmit control information including data transmission rate and PHY frame length information. Legacy devices conforming to the IEEE 802.11a / b / g / n / ax standards can decode the data from the various legacy fields (L-STF401, L-LTF402, L-SIG403) mentioned above. Following these legacy fields are RL-SIG404, EHT-SIG-A405, EHT-SIG-B406, EHT-STF407, EHT-LTF408, data field 409, and packet extension 410. Here, EHT stands for Extremely High Throughput. EHT-SIG-A405 contains information such as EHT-SIG-A1 and EHT-SIG-A2 necessary for receiving PPDU. The subfields that make up EHT-SIG-A1 and EHT-SIG-A2 contained in EHT-SIG-A405 and their descriptions are shown in Tables 1 and 2, respectively.

[0025] [Table 1]

[0026] [Table 2]

[0027] EHT-SIG-B406 contains information such as the Common field and User Block field necessary for receiving PPDUs.

[0028] EHT-STF407, following EHT-SIG-B406, stands for EHT Short Training Field, and its main purpose is to improve automatic gain control in MIMO transmission. EHT-LTF408 stands for EHT Long Training Field, and provides the receiver with a means to estimate the MIMO channel. Data field 409 may contain data for MIMO communication transmitted with the number of SS (Spatial Streams) indicated in the NSTS And Midamble Periodicity subfield of EHT-SIG-A1. In this embodiment, the data field is read when the BSS Color information contained in 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.

[0029] Figure 5 shows a sequence diagram of how the communication device 100 reads the data field of a frame transmitted from an AP that has not established a connection. In this embodiment, the communication device 100 reads the data field if the field containing information indicating the source of the frame transmitted from an AP that has not established a connection contains information of one of the APs participating in the Multi-AP communication.

[0030] In S501, communication devices 101-103, which operate as APs, perform connection processing with STAs in accordance with the IEEE 802.11 series standards. That is, Probe Request / Response, Association Request / Response, and Authentication Request / Response are sent and received between communication devices 101-103 and the STAs, respectively. Communication devices 101-103 establish a wireless link by sending and receiving the above frames with their respective STAs. Here, communication device 101, which is a Sharing AP, establishes a connection with STA_01, communication device 102, which is a Shared AP, establishes a connection with communication device 100 and STA_12, and communication device 103, which is a Shared AP, establishes a connection with STA_21. In S502, the Multi-AP communication system setup is performed. In the Multi-AP communication system setup, communication device 101, which is a Sharing AP, sends a trigger frame to communication devices 102 and 103, and communication devices 102 and 103, which receive the trigger frame, send a response frame to communication device 101. The trigger frame is a frame in which communication device 101 assigns a RU to each of communication devices 102 and 103, prompting each communication device to use its assigned RU to transmit predetermined information to communication device 101. The response frame includes identification information of the STA that has established a connection with communication devices 102 and 103, the MAC addresses of communication devices 102 and 103, and information about the network that communication devices 102 and 103 are building. The identification information of the STA is the MAC address or IP address of the STA. Furthermore, the information about the network that communication devices 102 and 103 are building is the SSID and / or BSSID and BSS Color. Here, BSS is an abbreviation for Basic Service Set. In this way, communication device 101, which is a Sharing AP, collects information about APs participating in the Multi-AP communication by receiving the response frame. Also, in S502, communication device 101 decides whether or not communication devices 102 and 103 will participate in the Multi-AP communication based on the information in the response frame transmitted by communication devices 102 and 103.Then, the Sharing AP, communication device 101, transmits the information about the APs participating in the Multi-AP communication, collected in S502, to the communication devices 102 and 103, which have been decided to participate in the Multi-AP communication. This allows the Shared APs, communication devices 102 and 103, to know the information about the APs participating in the Multi-AP communication. The information about the APs participating in the Multi-AP communication includes, but is not limited to, the MAC address, which is the identification information of the AP, and the BSS Color, which is information used to distinguish the network that the AP constructs.

[0031] Communication device 101 transmits information about APs participating in the Multi-AP communication shared in S502 to the STA (S503). In addition, information about APs participating in the Multi-AP communication is transmitted from the APs participating in the Multi-AP communication to the STAs that established a connection in S501. Communication device 101 transmits information about APs participating in the Multi-AP communication to STA_01, communication device 102 transmits it to communication device 100 and STA_12, and communication device 103 transmits it to STA_21. As a result, the STAs can learn about APs participating in the Multi-AP communication.

[0032] Communication device 101 transmits a frame to communication device 100, which is an STA with which a connection has not been established (S504). Here, the frame may be of any type: a management frame, a control frame, or a data frame. Alternatively, communication device 101 may perform sounding between each AP and each STA before transmitting the frame, and collect CSI between APs and STAs to understand the status of the destination communication device before transmitting the frame. Alternatively, communication device 101 may understand the status of the destination communication device from the information of STAs that have established connections with communication devices 102 and 103, received in S302, instead of CSI. Communication device 100 determines whether or not to read the frame based on the information about APs participating in the Multi-AP communication shared in S503 and the source information contained in the frame transmitted by communication device 101 (S505). The detailed flow of S505 will be explained in Figure 6 below.

[0033] Figure 6 is a flowchart showing the processing flow performed when the control unit 202 executes a program stored in the memory unit 201 of the communication device 100. This flowchart describes the processing flow for reading the data fields contained after the field containing the source information of a frame transmitted by a communication device 101 that has not established a connection with the communication device 100.

[0034] The flowchart is initiated when the communication device 100 detects the beginning of a frame transmitted by the communication device 101. In this embodiment, the flowchart is initiated by detecting L-STF, which is the beginning of the frame, but it is not limited to the beginning of the frame.

[0035] First, in S601, it is determined whether the detected frame conforms to the IEEE 802.11be standard. The standard is determined based on the modulation scheme and various parameters interpreted in the physical header of the detected frame. If S601 determines that the frame does not conform to the IEEE 802.11be standard, it is determined whether the destination information of the frame contained 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 may be a MAC address or a broadcast address, but is not limited to these. If it is determined in S604 that they match, S605 determines whether the information of the source communication device contained in the TA field matches the MAC address of the AP that has established a connection with the communication device 100. If it is determined in S605 that they match, the communication device 100 reads the information from the TA field onward of the frame transmitted by the communication device 101 (S606). If it is determined that neither S604 nor S605 matches, the communication device 100 will not read the information contained in the TA field and subsequent parts of the frame transmitted by the communication device 101 (S607).

[0036] If S601 determines that the frame standard type conforms to IEEE802.11be, then S602 determines whether the destination information of the frame contained 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 may be a MAC address or a broadcast address, but is not limited to these. If a match is determined in S602, then S503 determines whether the information of the source communication device contained in the TA field matches any of the information of APs participating in the Multi-AP communication that was shared. More specifically, S503 determines whether the information of the source communication device contained in the TA field of the frame transmitted by the communication device 101 matches any of the MAC addresses of APs participating in the Multi-AP communication that were shared. If a match is determined in S603, the communication device 100 reads the information from the TA field onward of the frame transmitted by the communication device 101 (S606). If it is determined that neither S602 nor S603 matches, the communication device 100 does not read the data field information contained after the TA field of the frame transmitted by the communication device 101 (S607).

[0037] In this embodiment, MAC addresses are used as an example of information about APs participating in Multi-AP communication, but BSS Color may also be used. If BSS Color is used, it is determined in S503 whether it matches either the BSS Color included in the frame's EHT-SIGA or the BSS Color of the network constructed by the APs participating in the Multi-AP communication that is shared.

[0038] Note that S601 may be omitted. In that case, the flowchart shown in Figure 6 will start from S602.

[0039] According to this embodiment, the communication device 100 can read data fields from the field containing information indicating the source of a frame transmitted from another communication device with which a connection has not been established.

[0040] In the above-described embodiment, an example was shown in which a communication device having the hardware configuration of Figure 2 executes the flowchart of Figure 6. However, a wireless chip having the storage unit, control unit, and communication unit of Figure 2 may also execute the flowchart of Figure 6. That is, the communication device of this embodiment may be a wireless chip having the storage unit, control unit, and communication unit of Figure 2.

[0041] Alternatively, 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 will implement the functions of the above-described embodiment, and the storage medium containing that program code will constitute the above-described device.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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. [Explanation of Symbols]

[0046] 201 Storage section 202 Control Unit 203 Functional Section 204 Input section 205 Output section 206 Communications Department 207 Antenna

Claims

1. A communication device, a receiving means for receiving first information related to a second other communication device that is shared between a first other communication device that has established a connection with the communication device and a second other communication device that has not established a connection with the communication device; a determining means for determining whether or not a first field included in a predetermined frame and indicating a source of the predetermined frame contains the first information received by the receiving means when the predetermined frame is received; reading means for reading data fields included in the first field and subsequent fields of the predetermined frame when the determining means determines that the first information is included; A communication device comprising:

2. 2. The communication device according to claim 1, wherein the communication device receives the first information from the first other communication device.

3. The predetermined frame further has a second field containing second information that is identification information of a device to which the predetermined frame is addressed; The communication device described in claim 1, characterized in that the reading means reads the data field contained after the first field of the specified frame when it is determined that the second information matches the identification information of the communication device and that the first information is contained in the first field.

4. 4. The communication device according to claim 3, wherein the second information is a MAC address or a broadcast address of a device that is the destination of the predetermined frame.

5. 5. The communication device according to claim 3, wherein the second field is an RA (Receiver Address) field.

6. 6. The communication device according to claim 1, wherein the predetermined frame is a frame conforming to the IEEE 802.11 standard series.

7. 7. The communication device according to claim 1, wherein the first information is a MAC address of the second other communication device or a BSS (Basic Service Set) Color, which is information for distinguishing a wireless network constructed by the second other communication device.

8. 8. The communication device according to claim 1, wherein the first field is a TA (Transmitter Address) field or an EHT (Extremely High Throughput)-SIG-A field.

9. 9. The communication device according to claim 1, wherein the first other communication device and the second other communication device operate as APs (Access Points) conforming to the IEEE 802.11 standard series.

10. A communication method for a communication device, comprising: a receiving step of receiving first information related to a second other communication device that is shared between a first other communication device that has established a connection with the communication device and a second other communication device that has not established a connection with the communication device; a determination step of determining whether or not a first field included in a predetermined frame and indicating a transmission source of the predetermined frame includes the first information received in the receiving step, when the predetermined frame is received; a reading step of reading data fields included in the first field and subsequent fields of the predetermined frame when it is determined that the first information is included in the predetermined frame by the determining step; A communication method for a communication device, comprising:

11. A program for causing a computer to function as each of the means of the communication device according to any one of claims 1 to 9.

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