Communication device, control method, and program

Abstract

To provide a specific mechanism to share information on TWT in different networks.SOLUTION: A communication device receives a radio frame including information on target wake time (TWT) in a first network constituted by a first communication device different from the communication device. The communication device transmits a predetermined frame including a predetermined element including information for identifying the first communication device and information on the TWT in the first network.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a communication device that performs wireless communication, a control method for the communication device, and a program. [Background technology]

[0002] The Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard series is known as the main communication standard for WLANs (Wireless Local Area Networks), and includes standards such as IEEE802.11a / b / g / n / ac / ax.

[0003] The IEEE802.11ax standard described in Patent Document 1 discloses that wireless communication is performed by orthogonal frequency-division multiple access (OFDMA). In the IEEE802.11ax standard, high peak throughput is realized by performing wireless communication by OFDMA. In addition, the IEEE802.11ax standard introduces a power saving technology called TWT (Target Wake Time). In the IEEE802.11ax standard, this TWT allows an AP (Access Point) and a STA (Station) to negotiate the interval between a Doze state in which frames are not transmitted or received and an Awake state in which frames are transmitted or received, so that the AP can control the timing of communication of each STA. As a result, the STA can reduce power consumption by reducing the time in the Awake state during the time when communication is not performed.

[0004] In addition, the IEEE802.11be standard, which is the successor to the IEEE802.11ax standard, is being developed. As a new function of the IEEE802.11be standard, a function such as multi-link communication, in which an AP and a STA establish multiple parallel links via multiple different frequency channels to communicate, is being considered. For example, Patent Document 2 describes a mechanism for establishing multiple links for multi-link communication. In addition, in the IEEE802.11be standard, low-latency communication using the above-mentioned TWT is being considered. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-50133 A [Patent Document 2] Patent Publication No. 2021-103805 Summary of the Invention [Problem to be solved by the invention]

[0006] The IEEE802.11be standard is currently considering R-TWT (Restricted TWT).

[0007] R-TWT is a mechanism that sets a period in a network called a Service Period (SP) during which only certain terminals in the network (BSS) can communicate, and during that period, only the specified terminals can be in an Awake state (a state capable of communication) and can communicate. By setting an SP in this way, terminals that are permitted to communicate in that SP can have exclusive access rights to the communication channel. On the other hand, terminals that are not permitted to communicate in that SP can save power during that period by, for example, going into a Doze state (a state in which communication is not possible).

[0008] However, the schedule of an SP is set for each network, and the schedule of the SP is not shared with other networks (OBSS). Therefore, a terminal that does not know the schedule of an SP of a different network may execute communication during an SP in a different network. This may cause the communication of a terminal that is permitted to communicate during an SP to be hindered by the communication of a terminal that does not know the SP. This may hinder the realization of low-latency communication using SP.

[0009] Therefore, one of the objectives of the present invention is to provide a specific mechanism for sharing information regarding TWTs in different networks. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, a communication device according to one embodiment of the present invention is a communication device having a receiving means for receiving a wireless frame including information regarding a Target Wake Time (TWT) of a first network established by a first communication device different from the communication device, and a transmitting means for transmitting a predetermined frame including a predetermined element including information identifying the first communication device and information regarding the TWT of the first network. Effect of the Invention

[0011] According to one aspect of the present invention, it is possible to share information about TWTs in different networks. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing an example of a network configuration. [Diagram 2] FIG. 2 is a diagram showing an example of a hardware configuration of a communication device. [Diagram 3] FIG. 2 is a diagram showing an example of a functional configuration of a communication device. [Figure 4] FIG. 13 is a diagram showing an example of a flowchart for setting TWT information. [Diagram 5]FIG. 13 is a diagram showing an example of a frame structure of a Reduced Neighbor Report Element. [Figure 6] FIG. 13 is a diagram showing an example of a Restricted TWT Schedule Info Subfield Value. [Figure 7] FIG. 13 is a diagram showing an example of a flowchart illustrating a process of sharing TWT information. [Figure 8] FIG. 13 is a diagram showing an example of a frame structure of a Neighbor Report Element. [Figure 9] FIG. 1 is a diagram showing an example of a frame structure of a TWT element. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0014] <First embodiment> (Network Configuration) FIG. 1 shows an example of a network configuration according to this embodiment. This embodiment is composed of a network 101, which is a first network, and a network 104, which is a second network different from the first network. In this embodiment, a STA MLD 103 operating as a terminal participates in a network 101 constructed by an AP MLD 102 operating as a base station. Also, a STA MLD 106 operating as a terminal station participates in a network 104 constructed by an AP MLD 105 operating as a base station. Note that AP MLD is an abbreviation for Access Point Multi-Link Device, and STA MLD is an abbreviation for Station Multi-Link Device. Also, STA MLD is also called non-AP MLD. Note that an MLD is a communication device having multiple STAs (or APs), and by having multiple STAs, an MLD can establish multiple links with opposing MLDs in parallel via different frequency channels. Also, multi-link communication can be performed via the established multiple links. Network 101 is a network identified by a first BSS (Basic Service Set), and network 104 is a network identified by a second BSS (Basic Service Set). When viewed from a terminal belonging to a certain network, such as AP MLD 102 or STA MLD 103, other networks different from the network to which the terminal belongs may be called OBSSs (Overlapping Basic Service Sets).

[0015] In this embodiment, the AP MLD 102, the STA MLD 103, the AP MLD 105, and the STA MLD 106 are, as an example, MLDs, but these communication devices do not have to be MLDs and may be AP 102, STA 103, AP 105, and STA 106, respectively.

[0016] Moreover, each communication device (AP MLD 102, STA MLD 103, AP MLD 105, STA MLD 106) is configured to be able to execute communication of wireless frames conforming to the IEEE802.11bn standard, which is the successor standard to the IEEE802.11be standard and has a maximum transmission speed of 46.08 Gbps. Note that IEEE is an abbreviation for Institute of Electrical and Electronics Engineers. The IEEE802.11bn standard, which is the successor standard to IEEE802.11be, has high reliability communication, low latency communication, and improved throughput during congestion as its main features. In addition, 802.11bn also has the goal of reducing power consumption in the AP. The wireless frame communicated according to the successor standard is also called UHR (Ultra High Reliability) PPDU. PPDU is an abbreviation for PLCP Protocol Data Unit, and PLCP is an abbreviation for Physical Layer Convergence Protocol.

[0017] The name UHR is a convenient name given to the goals and features of the successor standard, and may be a different name when the standard is completed. Similarly, the name IEEE802.11bn may be a different name when the standard is completed. Meanwhile, it should be noted that this specification and the appended claims are essentially applicable to all successor standards that are successors to the 802.11be standard. Each communication device can communicate at frequencies of 2.4 Hz, 3.6 GHz, 5 GHz, 6 GHz, 45 GHz, and 60 GHz, which are called millimeter waves. The frequency bands used by each communication device are not limited to these, and may use different frequency bands, such as the Sub1 GHz band. Also, each communication device can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, 540 MHz, and 640 MHz. The bandwidth used by each communication device is not limited to this, and may be a different bandwidth such as 240 MHz or 4 MHz.

[0018] Moreover, each communication device can realize multi-user (MU, Multi User) communication in which signals of multiple users are multiplexed by performing OFDMA communication conforming to the IEEE802.11ax / be / bn standard. OFDMA stands for Orthogonal Frequency Division Multiple Access. In OFDMA communication, a part of the Resource Unit of the divided frequency band is assigned to each STA so as not to overlap, and the carrier waves of each STA are orthogonal. Therefore, the AP can communicate with multiple STAs simultaneously in parallel within a specified bandwidth. Moreover, each communication device may support other communication standards such as Bluetooth (registered trademark), NFC, UWB, ZigBee, MBOA, etc. in addition to the IEEE802.11 series standard. Note that UWB stands for Ultra Wide Band, and MBOA stands for Multi Band OFDM Alliance. Also, NFC stands for Near Field Communication. UWB includes wireless USB, wireless 1394, WiNET, etc. Also, it may support communication standards for wired communication such as wired LAN.

[0019] Specific examples of the AP MLD 102 and the AP MLD 105 include, but are not limited to, a wireless LAN router and a personal computer (PC), and may be any communication device capable of operating as an access point (AP). Each AP MLD may be an information processing device such as a wireless chip capable of performing wireless communication conforming to the IEEE802.11bn standard. Specific examples of the STA MLD 103 and the STA MLD 106 include, but are not limited to, a camera, a tablet, a smartphone, a PC, a mobile phone, a video camera, a headset, a network camera, a printer, a projector, and smart glasses. Each STA MLD may be an information processing device such as a wireless chip capable of performing wireless communication conforming to the IEEE802.11bn standard.

[0020] In addition, as an example of a network configuration in this embodiment, network 101 and network 104, each consisting of one AP MLD and one STA MLD, are configured adjacent to each other, but the number of networks, APs, and STAs are not limited to this and may include multiple of each.

[0021] (Hardware configuration of each communication device) 2 shows an example of the hardware configuration of each communication device. Each communication 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.

[0022] The storage unit 201 is configured with both or either one of a ROM and a RAM, and stores various information such as programs for performing various operations described below and communication parameters for wireless communication. RAM stands for Random Access Memory, and ROM stands for Read Only Memory. Note that, as the storage unit 201, in addition to memories such as ROM and RAM, storage media such as non-volatile storage devices such as hard disks and SSDs (Solid State Drives) may be used.

[0023] The control unit 202 is configured with, for example, a processor such as a CPU or MPU, an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), etc. Here, CPU stands for Central Processing Unit, and MPU stands for Micro Processing Unit. The control unit 202 executes the programs stored in the storage unit 201 and controls the entire device by operating hardware circuits such as the ASIC. The control unit 202 may control the entire device in cooperation with the programs stored in the storage unit 201 and an OS (Operating System).

[0024] The control unit 202 controls the functional unit 203 to perform predetermined processing such as imaging, printing, and projection. The functional unit 203 is hardware for the device to perform predetermined processing. For example, when the communication device is a camera such as a digital still camera or a smartphone having a camera, the functional unit 203 is an imaging unit that performs imaging processing of surrounding images via a camera unit (not shown) of the communication device. For example, when the communication device is a printer, the functional unit 203 is a printing unit that performs printing processing on a sheet such as paper based on print data obtained from the outside through wireless communication. For example, when the communication device is a projector or smart glasses, the functional unit 203 is a projection unit that performs projection processing of image data or video data obtained from the outside through wireless communication. In the case of smart glasses, the projection surface is the retina of an end user. The data processed by the functional unit 203 may be data stored in the storage unit 201, or may be data communicated with other APs or STAs via the communication unit 206 described later. Furthermore, a communication device such as the AP 101 can provide a network storage function such as a NAS (Network Attached Storage). This function is provided to other communication devices as a Web service such as a network storage service. For example, a communication device such as an STA connects to a network storage service provided by an AP MLD or the like using a protocol such as SMB, FTP, or WebDAV. The communication device such as an STA then uploads files to the storage service and downloads files from the storage. The data communication for uploading and downloading is also realized by communicating UHR PPDU between devices.

[0025] The input unit 204 receives various operations from the user. The output unit 205 performs various outputs to the user. Here, the output by the output unit 205 includes, for example, at least one of display on a screen, audio output by a speaker, and vibration output. Note that both the input unit 204 and the output unit 205 may be realized by one module, such as a touch panel. The output unit 205 functions as a display unit that presents information to the user. Also, the input unit 204 functions as a receiving unit that receives user operations.

[0026] The communication unit 206 controls wireless communication conforming to the IEEE802.11 standard series and IP communication. In this embodiment, the communication unit 206 can execute communication control for transmitting and receiving UHR PPDU, which is a wireless frame of the UHR standard, and PPDU corresponding to the earlier standard in cooperation with the antenna 207. The antenna 207 is an antenna capable of transmitting and receiving signals in at least one of the frequency bands of the sub-GHz band, the 2.4 GHz band, the 5 GHz band, the 6 GHz band, and the millimeter wave band, for example.

[0027] When the communication device is compatible with the above-mentioned NFC standard, Bluetooth standard, wired communication standard, or the like, the communication unit 206 may be configured to control wireless communication or wired communication that complies with these communication standards.

[0028] (Functional configuration of communication device) Next, Fig. 3 shows a block diagram showing an example of the functional configuration of each communication device in this embodiment. In this embodiment, each functional block is stored as a program in the storage unit 201, and the function is implemented by executing the program by the control unit 202. By executing the program, the control unit 202 realizes each function by controlling each hardware and calculating and processing information. Note that some or all of the functional blocks may be implemented as hardware. In this case, some or all of the functional blocks are configured by, for example, an ACIC (Application Specific Integrated Circuit).

[0029] In this embodiment, each communication device includes a TWT information acquisition unit 301, a frame generation unit 302, a frame transmission / reception unit 303, a multi-link control unit 304, and a UI control unit 305.

[0030] The TWT information acquisition unit 301 acquires TWT information set in different networks from management frames such as Beacon frames, Probe Response frames, and Association Response frames from different networks.

[0031] The frame generation unit 302 generates a radio frame to be transmitted via a frame transmission / reception unit described later. In this embodiment, based on the TWT information of a different network acquired by the TWT information acquisition unit 301, a frame is generated for sharing the TWT information with other communication devices.

[0032] The frame transmitting / receiving unit 303 is configured to include an antenna and a circuit for transmitting and receiving wireless frames (or signals) to and from other wireless communication devices, and a program for controlling them. The frame transmitting / receiving unit 303 executes communication control of the wireless LAN based on the frames generated by the frame generating unit 302 in accordance with the IEEE802.11 standard series.

[0033] The multi-link control unit 304 controls processes related to link establishment, such as link establishment process for establishing one or more links used for wireless communication with the opposing MLD, communication start process, link addition / deletion process after link establishment, communication end process for deleting all links, etc. The link establishment process mainly consists of authentication process, association process, and 4-Way-Hand-Shake (4WHS) process.

[0034] The UI control unit 305 is composed of hardware related to a user interface such as a touch panel or buttons for accepting operations from a user, and a program for controlling them. For example, the multilink control unit 304 selects a partner device to which a communication device will connect by accepting an operation from a user via the UI control unit 305. The multilink control unit 304 also accepts an operation from a user via the UI control unit 306, and performs processing for selecting and determining an STA provided in each communication device to be used when each communication device establishes a link. The UI control unit 306 may further have a function for showing information such as audio output to the user.

[0035] (TWT information) Next, the TWT information will be described. In this embodiment, the Target Wake Time (TWT) information includes at least information about the Service Period (SP), but the TWT information is not limited to this and may further include information about other TWTs. For example, the TWT information may be configured to include a Traffic Identifier (TID) indicating the type of data that can be transmitted in the SP, information about a TWT group indicating a group of multiple STAs that share a common SP, and the like.

[0036] The SP is set through coordination between the AP and the STA in the network, and indicates the period during which the STA is in an awake state (a state in which communication is possible). Generally, the STA is in a doze state (a state in which communication is not possible) outside the SP, but the STA may be configured to communicate outside the SP. Within the SP, the STA is in an awake state and transmits and receives frames. On the other hand, outside the SP, the STA is in a doze state, which enables power saving. The TWT information is not limited to these, and may be configured to include information included in the TWT Parameter information described later. The information related to the SP is, for example, information related to the start timing of the SP, information related to the time from the start to the end of the SP, information related to the interval between the start timing of each SP, and the like.

[0037] (TWT information setting) Next, a flowchart for setting TWT information in the AP MLD 102 and the STA MLD 103 of the network 101 will be described.

[0038] FIG. 4 illustrates an example of a flowchart in which the AP MLD 102 receives a TWT Request from the STA MLD 103 and sets TWT information by transmitting a TWT Response in response to the TWT Request.

[0039] 4 is started when the STA MLD 103 sets or updates TWT information. In this embodiment, the setting of TWT information at the time of initial link setup between the AP MLD 102 and the STA MLD 103 will be described.

[0040] In S401, the AP MLD 102 receives an Association Request frame including a TWT Request transmitted by the STA MLD 103 via the communication unit 206. Here, the TWT Request is information indicating that the STA MLD requests the AP MLD to set TWT information. The TWT Request includes TWT information such as information indicating whether the source STA supports TWT, AID (Association Identifier), SP start timing, time from the start to the end of the SP, and information regarding the SP period and interval.

[0041] In S402, the AP MLD 102 transmits an Association Response frame including a TWT Response to the STA MLD 103 via the communication unit 206. The TWT Response is information indicating approval of setting the information related to the start time and end time of the SP and the period of the SP of the TWT Request received in S401 as TWT information. For example, the AP MLD 102 may be configured to indicate approval by including the same value as the TWT Request in the TWT Response. Furthermore, if the AP MLD 102 does not approve the received TWT Request, it may be configured to indicate a value different from the TWT Request in the TWT Response.

[0042] Based on the TWT Response transmitted by the AP MLD 102 in S403, the TWT information is set in the AP MLD 102 and the STA MLD 103 and a link is established.

[0043] After setting the TWT information in the AP MLD 102 and the STA MLD 103, the AP MLD 102 periodically transmits a Beacon frame including the set TWT information (S404). This allows the AP MLD 105 to receive and acquire the TWT information in the AP MLD 102 and the STA MLD 103.

[0044] Note that, in FIG. 4, an example of a flow for setting TWT information at the time of initial link setup between AP MLD 102 and STA MLD 103 is described, but this is not limited to this, and this flow may be started based on STA MLD 103 sending a TWT Request after link setup.

[0045] Furthermore, in this embodiment, the flow of setting the TWT information in the AP MLD 102 and the STA MLD 103 has been described, but the AP MLD 105 and the STA MLD 106 may be configured to set the TWT information and establish a link using a similar flow.

[0046] (Elements used to share TWT information) First, before describing the flow of the TWT information sharing process, elements contained in a radio frame used when sharing TWT information used in the TWT information sharing process will be described.

[0047] 5 shows an example of a frame format of the Reduced Neighbor Report Element in this embodiment. In this embodiment, the Reduced Neighbor Report Element is used to share TWT information of other networks with the network that the device establishes or connects to. In the following description, the fields included in the Reduced Neighbor Report Element are described using only the names of the fields, and the fields are omitted.

[0048] The Reduced Neighbor Report Element shown in FIG. 5 includes an Element ID 501, a Length 502, and Neighbor AP Information Fields 503. The Element ID 501 is an identifier for identifying an Information Element, and in this embodiment, includes an identifier indicating a Reduced Neighbor Report Element. The Length 502 is a field indicating the data length of an Element, and in this embodiment, includes information indicating the data length of the Neighbor AP Information Fields 503. The Neighbor AP Information Fields 503 is a field indicating information of a different network, and in this embodiment, includes TWT information of the different network. The information included in the Neighbor AP Information Fields 503 will be described later.

[0049] Each communication device generates the Reduced Neighbor Report Element shown in FIG. 5 in order starting from Element ID 501, and transmits it to other communication devices. In this case, each communication device generates all fields in the element before transmitting it. Specifically, each communication device generates all of Element ID 501, Length 502, and Neighbor AP Information Fields 503 before transmitting it to other communication devices. Alternatively, each AP MLD may be transmitted in parallel with the generation of the fields. Specifically, each communication device may transmit, for example, the generated Element ID 501 and the Length 502 in parallel.

[0050] Each communication device transmits a MAC (Medium Access Control) frame, such as a Beacon frame or a Probe Response frame, including the Reduced Neighbor Report Element shown in Fig. 5. In addition to these MAC frames, each communication device can also add this element to MAC frames, such as an Association Response frame or a Reassociation Response frame.

[0051] Neighbor AP Information Fields 503 include one or more pieces of Neighbor AP Information. Each piece of Neighbor AP Information includes a TBTT Information Header 504, an Operating Class 505, a Channel Number 506, and a TBTT Information Set 507. Each AP indicated by each piece of Neighbor AP Information may be called a reported AP. TBTT is an abbreviation for Target Beacon Transmission Time. The TBTT Information Header 504 includes information indicating the data length of the TBTT Information Set 507 and information indicating the number of TBTT Information fields included in the TBTT Information Set 507. The number of TBTT Information fields is indicated by the number of fields actually included in the TBTT Information Set 507 minus 1. The Operating Class 505 indicates the start frequency of the channel. Also, the primary channel of the reported AP is indicated based on the information indicated by the Operating Class 505 and the Channel Number 506.

[0052] The TBTT Information Set 507 includes one or more pieces of TBTT Information. The information included in each piece of TBTT Information included in the TBTT Information Set 507 will be described later. Note that the Neighbor AP Information Fields 503 can include information on a plurality of other APs by including a plurality of pieces of Neighbor AP Information. Furthermore, a communication device that receives a Reduced Neighbor Report Element can efficiently control communication by identifying the primary channel based on the Operating Class 505 and Channel Number 506.

[0053] The TBTT Information Set 507 includes one or more pieces of TBTT Information. Each piece of TBTT Information includes a Neighbor AP TBTT Offset 508, a BSSID 509, a Short SSID 410, a BSS Parameters 511, a 20MHz PSD 511, an MLD Parameters 513, and TWT information 514. The Neighbor AP TBTT Offset 508 indicates an offset in Time Units (TUs) from the TBTT immediately before the reported AP to the next TBTT. The BSSID 509 indicates the Basic Service Set Identifier (BSSID) of the reported AP. The Short SSID 510 is a 32-bit value calculated from the Service Set Identifier (SSID) of the network that the reported AP establishes. The BSS Parameters 511 indicate various information related to the reported AP indicated by the BSSID 509. The 20MHz PSD 511 is information indicating the maximum transmission power, and indicates, for example, the maximum transmission power corresponding to the 20MHz primary channel of the reported AP. MLD parameters 513 is information about the AP MLD to which the reported AP belongs, and includes, for example, an AP MLD ID that is an identifier of the AP MLD and a Link ID that is an identifier of the link of the reported AP in the AP MLD. TWT information 514 is a field that includes TWT information of the reported AP, and the element includes TWT information of other networks for sharing.

[0054] The TWT information 514 includes Control 515 and TWT Parameter information 516. The Control 515 is information related to information included in the TWT Parameter information 516, and includes, for example, information indicating whether the TWT information is a broadcast TWT, an individual TWT, or TWT information indicating a TBTT interval. Note that the broadcast TWT is a TWT in which TWT information is set between an AP and a plurality of STAs, and the individual TWT is a TWT in which TWT information is set on a one-to-one basis between an AP and a STA. The TWT Parameter information 516 includes Request Type 517, Target Wake Time 518, Nominal Minimum TWT Wake Duration 519, TWT Wake Interval Mantissa 520, Broadcast TWT Info 521, and Restricted TWT Traffic Info 522. The Request Type 517 includes, for example, a TWT flow identifier for identifying a flow of a TWT controlled based on the TWT information included in the TWT information. Target Wake Time 518 is information indicating the time until the next SP, and includes a positive integer corresponding to a Timing Synchronization Function (TSF) time requesting the STA to be released from the Doze state. Nominal Minimum TWT Wake Duration 519 is information indicating an expected time from the start to the end of an SP, and includes information indicating the expected minimum time that the STA needs to be in the Awake state in order for the STA to complete the exchange of radio frames after the Doze state is released. TWT Wake Interval Mantissa 520 is information indicating the interval of the start timing of each SP, and includes information indicating the value of the mantissa part of the value indicating the interval at which the STA releases the Doze state. The information included in Broadcast TWT Info 521 will be described later.Restricted TWT Traffic Info 522 specifies, in a bitmap format, a Traffic Identifier (TID) for a specific radio frame in downlink (DL) and uplink (UL) communication.

[0055] Broadcast TWT Info 521 includes Restricted TWT Traffic Info Present 523, Restricted TWT Schedule Info 524, Broadcast TWT ID 525, and Broadcast TWT Persistence 526. Restricted TWT Traffic Info Present 523 includes information indicating whether Restricted TWT Traffic Info 522 is included. Restricted TWT Schedule Info 524 will be described later. Broadcast TWT ID 525 stores information identifying the TWT information of the broadcast TWT set by the reported AP. Broadcast TWT Persistence 526 stores information indicating the number of TBTTs in the SP indicated by the TWT information.

[0056] Restricted TWT Schedule Info 524 will be explained with reference to Fig. 6. Fig. 6 is a diagram for explaining the values ​​included in Restricted TWT Schedule Info 524 and the meanings indicated by these values. Values ​​0 to 3 are used when the AP notifies STAs in its own BSS of the TWT schedule. 0 indicates that the TWT is idle, while 1 and 3 indicate that the TWT schedule is active. 2 indicates that the schedule is active but that new participation is unlikely. The following values, 4 and 5, mean that the TWT information indicates the TWT schedule of another network (OBSS).

[0057] When Restricted TWT schedule Info 524 contains a value of 4, it indicates that the TWT information is TWT information of another network and the TWT schedule based on the TWT information is active in another BSS, and when the field 524 contains a value of 5, it indicates that the TWT information is TWT information of another network and the TWT schedule based on the TWT information is idle in another BSS.

[0058] (TWT information sharing process) Next, an example of a flowchart of a process in which the AP MLD 105 shares the TWT information of the network 101 with the STA MLD 106 using the above-mentioned Reduced Neighbor Report Element will be described with reference to FIG. In this embodiment, the AP MLD 105 acquires the TWT information of the network 101 from a wireless frame (including the TWT information of the network 101 transmitted by the AP MLD 102). The AP MLD 105 then shares the acquired TWT information of the network 101 with the STA MLD 106 of the network 104. This flowchart shows processing executed by the control unit 202 reading and executing a computer program stored in the storage unit 201. For example, this flowchart is started immediately after the AP MLD 105 transmits a Beacon frame that it transmits periodically. This flowchart may also be started in response to the AP MLD 105 receiving a wireless frame such as a Beacon frame, Probe Response frame, or Association Response frame from the AP MLD 102 constituting a different network. This flowchart shows an excerpt of the processing related to sharing the TWT information of the BSS with the STAs of the BSS.

[0059] First, in S701, the AP MLD 105 receives a wireless frame transmitted by the AP MLD 102 (for example, a Beacon frame transmitted by the AP MLD 102 in S404) via the frame transceiver unit 303. If the wireless frame contains TWT information, the process proceeds to S702, and if the wireless frame does not contain TWT information, the process ends. The wireless frame received in S701 is a MAC frame transmitted by the AP MLD 102, and is assumed to be, for example, a management frame such as a Beacon frame, a Probe Response frame, or an Association Response frame, but is not limited to this. For example, a control frame or an action frame may also be used.

[0060] Next, in S702, the TWT information acquisition unit 301 of the AP MLD 105 acquires the TWT information of the network 101 from the wireless frame including the TWT information received in S701.

[0061] In S703, the AP MLD 105 judges whether or not a predetermined period has elapsed since the start of this flow. The predetermined period in this embodiment is the transmission interval of the Beacon frame transmitted by the AP MLD 105. That is, the AP MLD 105 in this embodiment judges whether or not a predetermined period (for example, 100 TU) has elapsed since the transmission of the previous Beacon frame. If it is judged in S703 that the predetermined period has elapsed (S703, Yes), the process proceeds to S704. If it is judged in S703 that the predetermined period has not elapsed (S703, No), the process proceeds to S701.

[0062] Next, in S704, it is determined whether TWT information of a different BSS has been acquired within a predetermined period. If it is determined in S704 that TWT information of a different BSS has been acquired within the predetermined period (S704, Yes), the process proceeds to S705. If it is determined that TWT information of a different BSS has not been acquired within the predetermined period (S704, Yes), the process proceeds to S701.

[0063] Then, in S705, the AP MLD 105 stores the TWT information of the network 101 acquired in S702 in the above-mentioned Reduced Neighbor Report Element, and transmits a wireless frame including the element to the STA MLD 106 via the frame transmission / reception unit 303. In the element, the Restricted TWT schedule Info subfield is set to 4. Note that the wireless frame transmitted by the AP MLD 105 in S705 is a MAC frame, and is assumed to be, for example, a management frame such as a Beacon frame, a Probe Response frame, or an Association Response frame, but is not limited thereto. For example, a control frame or an action frame may be used. Note that in this embodiment, an example in which only the TWT information of the network 101 is included as the TWT information of the different network has been described, but is not limited thereto. For example, it is assumed that there are multiple networks other than the network 104 around the AP MLD 105, and there is a case in which the TWT information of multiple different BSSs is received before a predetermined period of time has elapsed. The TWT information sharing process in this case will be briefly described using the above-mentioned flow. First, the AP MLD 105 receives a wireless frame including TWT information of a first different BSS in S701. Then, it acquires TWT information of the first BSS from the received wireless frame. Then, it receives a wireless frame including TWT information of a second different BSS before a predetermined period has elapsed (S703, No and S701). Next, it acquires TWT information of the second BSS from the received wireless frame. Then, after the predetermined period has elapsed (S703, Yes), it stores the acquired TWT information of the first BSS and the TWT information of the second BSS in a Reduced Neighbor Report Element, and transmits a wireless frame including the element to the STA MLD 106 via the frame transmission / reception unit 303 (S705). In this way, when TWT information of a plurality of networks is received within a predetermined period, the TWT information of the plurality of networks is shared at once in S507. After transmitting a wireless frame including TWT information in S705, the AP MLD 105 advances the process to S706.In S706, the AP MLD 105 judges whether or not to stop the network. If it is judged that the network should be stopped, the process of providing the network is terminated and the series of processes is terminated. On the other hand, if it is not judged that the network should be stopped, the process proceeds to S701 and a series of notification controls are performed. Specifically, the AP MLD 105 may judge that the network should be stopped when a shutdown operation or power OFF operation (not shown) is received.

[0064] In this way, the AP MLD 105 stores the TWT information of the network 101 received from the AP MLD 103 in the above-mentioned Reduced Neighbor Report Element and transmits it to the STA MLD 106, thereby making it possible to share information on the TWT of different networks with the network to which the own device belongs. The AP MLD 105 may be configured to transmit at least information on the Target Wake Time 518, the Nominal Minimum TWT Wake Duration 519, and the TWT Wake Interval Mantissa 520 as the above-mentioned TWT information in S703. Each piece of information is information on the start timing of the SP in the other network, information on the time of the SP, and information on the interval of the start timing of each SP, respectively. Therefore, the STA MLD 106 can recognize the start timing of the next SP in the other network by recognizing the information contained in the Target Wake Time 518. Also, the STA MLD 106 can recognize the time of the SP in the other network by recognizing the information contained in the Nominal Minimum TWT Wake Duration 519. In addition, the STA MLD 106 can recognize the information contained in the TWT Wake Interval Mantissa 520, thereby recognizing the interval of the start timing of the SP of another network.

[0065] A STA connected to the AP MLD 105, represented by the STA MLD 106, etc., performs transmission suppression control so as not to perform its own data transmission processing during the SP of the recognized other network.

[0066] As described above, this allows the STA MLD 106 to grasp the start timing and time of the SP of the network 101, and makes it possible to suppress transmission in the SP of the other network that has been grasped. Therefore, it becomes possible to prevent interference with communication in the SP of the other network.

[0067] In the above-mentioned control in Fig. 7, the transmission interval of the Beacon frame is used as an example of a period for collecting the TWT of the OBSS, and the TWT information of the OBSS received during that period is notified to the STA of the BSS. However, this is not limited to this. For example, the AP MLD 105 can be configured to manage the TWT information transmitted by the AP of the OBSS in association with the last acquisition time, and to notify the STA of the BSS of the TWT information of the OBSS acquired within a predetermined reference time (for example, within one minute).

[0068] <Second embodiment> In the first embodiment, the AP MLD 105 shares the TWT information of the network 101 with the STA MLD 106 by using the Reduced Neighbor Report Element. In the second embodiment, an example will be described in which a Neighbor Report Element is used instead of the above-mentioned Reduced Neighbor Report Element. Note that the hardware configuration and functional configuration of each communication device in this embodiment are similar to those in the first embodiment, and therefore a description thereof will be omitted. In addition, the setting of the TWT information between the AP MLD 102 and the STA MLD 103 in the network 101 described using FIG. 4 and the process in which the AP MLD 105 shares the TWT information of the network 101 with the STA MLD 106 described using FIG. 7 are also similar to those in the first embodiment, and therefore a description thereof will be omitted.

[0069] The Neighbor Report Element in this embodiment will be described with reference to Fig. 8. The AP MLD 105 stores the TWT information of the different BSSs acquired in the above-mentioned S702 in the element, and transmits a wireless frame including the element to the STA MLD 106 via the frame transmission / reception unit 303. Note that the wireless frame including the element is a MAC frame, and is assumed to be, for example, a management frame such as a Beacon frame, a Probe Response frame, or an Association Response frame, but is not limited to this. For example, a control frame or an action frame may also be used.

[0070] 8 includes Element ID 801, Length 80, BSSID 803, BSSID Information 804, Operating Class 805, Channel Number 806, PHY Type 807, and Optional Subelement 808. Element ID 801, Length 80, BSSID 803, BSSID Information 804, Operating Class 805, and Channel Number 806 include the same information as the above-mentioned fields of the same names, so description thereof will be omitted. PHY Type 807 indicates the PHY type of the AP indicated by BSSID 803.

[0071] Optional Subelement 808 includes Subelement ID 809, Length 810, Control 515 and TWT Parameter Information 516.

[0072] In this way, the AP MLD 105 can share the TWT information of the network 101 with the STA MLD 106 by using the above-mentioned Neighbor Report Element.

[0073] <Third embodiment> In the third embodiment, the AP MLD 105 shares the TWT information of the network 101 with the STA MLD 106 by using a TWT Element instead of each of the above-mentioned elements.

[0074] In this embodiment, the hardware configuration and the functional configuration of each communication device are the same as those in the first embodiment, and therefore the description thereof will be omitted. Also, the setting of the TWT information between the AP MLD 102 and the STA MLD 103 in the network 101 described with reference to Fig. 4 and the process in which the AP MLD 105 shares the TWT information of the network 101 with the STA MLD 106 described with reference to Fig. 7 are the same as those in the first embodiment, and therefore the description thereof will be omitted.

[0075] The TWT Element in this embodiment will be described with reference to Fig. 9. The AP MLD 105 stores the TWT information of the different BSSs acquired in the above-mentioned S702 in the element, and transmits a wireless frame including the element to the STA MLD 106 via the frame transceiver 303. Note that the wireless frame including the element is a MAC frame, and is assumed to be, for example, a management frame such as a Beacon frame, a Probe Response frame, or an Association Response frame, but is not limited to this. For example, it may be a control frame or an action frame.

[0076] The TWT Element shown in FIG. 9 includes an Element ID 801, a Length 80, a Control 515, and TWT Parameter Information 903.

[0077] In this embodiment, the TWT Parameter Information 903 included in the TWT Element further includes a BSSID 904 in addition to the above-mentioned fields. The BSSID 904 stores information indicating the BSSID of the AP to which the TWT information indicated by the TWT Parameter Information 903 is set. Note that in this embodiment, the BSSID 904 is stored immediately after the Restricted TWT Traffic Info 522, but is not limited to this. For example, the BSSID 904 may be configured to be stored immediately after the Broadcast TWT Persistence 526, and may be configured to be stored at least in the TWT Parameter Information 903 included in the TWT Element. This allows the STA to identify which network the TWT information indicated by the TWT Element is related to. Also, even if a plurality of other networks exist, it is possible to identify which network the information of each TWT is related to.

[0078] In this way, the AP MLD 105 can share the TWT information of the network 101 with the STA MLD 106 by using the above-mentioned TWT Element.

[0079] <Other embodiments> In each of the above-mentioned embodiments, the flow in which the AP MLD shares the TWT information of another network with the STA MLD has been described, but the present invention is not limited to this. For example, when the STA MLD receives and acquires the TWT information of another network, the STA MLD may be configured to share the TWT information of the other network using any of the above-mentioned elements.

[0080] In addition, in each of the above-described embodiments, the TWT information of other networks is shared, but this is not limited thereto, and each element may be configured to share only information related to the R-TWT.

[0081] Also, at least a part or all of the flowcharts of AP MLD 105 shown in Fig. 4 and Fig. 7 may be realized by hardware. When realizing by hardware, for example, a specific compiler may be used to generate a dedicated circuit on FPGA from a computer program for realizing each step, and this may be used. FPGA is an abbreviation for Field Programmable Gate Array. Also, a gate array circuit may be formed in the same manner as FPGA, and realized as hardware. Also, it may be realized by ASIC (Application Specific Integrated Circuit).

[0082] The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

[0083] The disclosure of each of the above-described embodiments includes the following configurations.

[0084] (Configuration 1) A communication device, comprising: A receiving means for receiving a wireless frame including information regarding a Target Wake Time (TWT) of a first network established by a first communication device different from the communication device; a transmitting means for transmitting a predetermined frame including a predetermined element including information for identifying the first communication device and information regarding the TWT of the first network; A communication device comprising:

[0085] (Configuration 2) an acquisition means for acquiring information about the TWT of the first network based on the wireless frame received by the receiving means; and a generating means for generating the predetermined frame to be transmitted by the transmitting means, based at least on information regarding the TWT of the first network acquired by the acquiring means. 2. The communication device according to configuration 1.

[0086] (Configuration 3) When the communication device is not participating in the first network, the transmitting means transmits the predetermined frame including the predetermined element including information for identifying the first communication device and information related to the TWT. 3. The communication device according to configuration 1 or 2.

[0087] (Configuration 4) The network configuration device further includes a construction unit for constructing a second network. 4. The communication device according to claim 1, wherein the first and second communication devices are connected to each other.

[0088] (Configuration 5) The communication device further includes an establishment unit for establishing a link with a second communication device different from the communication device; The establishing means is capable of establishing a plurality of links with the second communication device via different frequency channels. 5. The communication device according to claim 1, wherein the first and second communication devices are connected to each other.

[0089] (Configuration 6) The predetermined frame is a management frame. 6. The communication device according to claim 1, wherein:

[0090] (Configuration 7) The communication device is an Access Point Multi-Link Device that complies with the IEEE 802.11 series standard. 7. The communication device according to claim 1, wherein:

[0091] (Configuration 8) The predetermined element is a Reduced Neighbor Report Element. The information identifying the first communication device and the information regarding the TWT of the first network are included in a Reduced Neighbor Report Element. 8. The communication device according to any one of configurations 1 to 7,

[0092] (Configuration 9) The predetermined element is a Neighbor Report Element, The information identifying the first communication device and the information regarding the TWT of the first network are included in a Neighbor Report Element. 8. The communication device according to any one of configurations 1 to 7,

[0093] (Configuration 10) The predetermined element is a TWT Element, The information for identifying the first communication device and the information regarding the TWT of the first network are included in a TWT Element. 8. The communication device according to any one of configurations 1 to 7, [Explanation of symbols]

[0094] 101, 104 Network 102, 105 AP MLD 103, 106 STA MLD

Claims

1. A communication device, comprising: A receiving means for receiving a wireless frame including information regarding a Target Wake Time (TWT) of a first network established by a first communication device different from the communication device; a transmitting means for transmitting a predetermined frame including a predetermined element including information identifying the first communication device and information regarding the TWT of the first network; A communication device comprising:

2. an acquisition means for acquiring information about the TWT of the first network based on the radio frame received by the receiving means; A generating means for generating the predetermined frame to be transmitted by the transmitting means based at least on the information related to the TWT of the first network acquired by the acquiring means.

2. The communication device according to claim 1 .

3. When the communication device is not participating in the first network, the transmitting means transmits the predetermined frame including the predetermined element including information for identifying the first communication device and information regarding the TWT.

2. The communication device according to claim 1 .

4. The network configuration device further includes a configuration unit for configuring a second network.

2. The communication device according to claim 1 .

5. The communication device further includes an establishment unit for establishing a link with a second communication device different from the communication device; The establishing means is capable of establishing a plurality of links with the second communication device via different frequency channels.

2. The communication device according to claim 1 .

6. The predetermined frame is a management frame.

2. The communication device according to claim 1 .

7. The communication device is an Access Point Multi-Link Device conforming to the IEEE 802.11 series standard.

2. The communication device according to claim 1 .

8. The predetermined element is a Reduced Neighbor Report Element. The information identifying the first communication device and the information regarding the TWT of the first network are included in a Reduced Neighbor Report Element. The communication device according to any one of claims 1 to 7.

9. The predetermined element is a Neighbor Report Element, The information identifying the first communication device and the information regarding the TWT of the first network are included in a Neighbor Report Element. The communication device according to any one of claims 1 to 7.

10. The predetermined element is a TWT Element, The information for identifying the first communication device and the information regarding the TWT of the first network are included in a TWT Element. The communication device according to any one of claims 1 to 7.

11. A method for controlling a communication device, comprising: a receiving step of receiving a wireless frame including information regarding a Target Wake Time (TWT) of a first network established by a first communication device different from the communication device; a transmitting step of transmitting a predetermined frame including a predetermined element including information identifying the first communication device and information regarding the TWT of the first network; 13. A method for controlling a communication device, comprising:

12. A program for causing a computer to function as the control method for a communication device according to claim 11.

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