Communication device, information processing apparatus, control method, and program

Abstract

To appropriately determine transmission power that is set when a coordinated AP communicates with a STA.SOLUTION: A communication device executes radio communication conforming to the IEEE802.11 series standard, and has communication means that performs data communication with a station in cooperation with an access point. The communication means transmits, to the access point, a frame indicating that the access point communicates with the station, and the frame includes information identifying the access point and information related to transmission power.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a device for controlling communications. [Background technology]

[0002] In recent years, with the increase in the amount of data being communicated, the development of communication technologies such as wireless LANs (Local Area Networks) is progressing. The IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard series is known as the main communication standard for wireless LANs. The IEEE 802.11 standard series includes standards such as IEEE 802.11a / b / g / n / ac / ax / be (Patent Document 1).

[0003] For example, the IEEE802.11be standard considers Multi-Link communication, in which one AP (Access Point) establishes multiple links with one STA (Station) via multiple different frequency channels and communicates in parallel. Note that the two or more links may be selected from the same frequency band (2.4GHz, 3.6GHz, 4.9GHz, 5GHz, or 6GHz), or each may be selected from a different frequency band. APs and STAs that support Multi-Link are called AP MLD (Multi-Link Device) and STA MLD, respectively.

[0004] In addition, methods are being considered for improving usability using Multi-Link in the successor standard to IEEE802.11be.

[0005] For example, there is distributed MIMO technology, which is based on a technology called MIMO (multi-user multi-output), which uses multiple transmitting and receiving antennas at the same time and on the same channel. In distributed MIMO, in an environment where multiple APs and multiple STAs exist, the APs share information about the communication status and the status of each AP, and data is sent from the AP to the STAs at the same time. By cooperatively transmitting from multiple APs, the number of spatial streams can be increased compared to the case of a single AP, and this is expected to improve throughput.

[0006] Another example is a technology called cooperative beamforming. When an AP transmits data to a STA in a basic service set (BSS), it uses an antenna pattern that provides high antenna gain in the direction of the STA to which the data is to be transmitted, and low antenna gain in the direction of STAs in the BSS of other APs. By setting antenna patterns, adjusting transmission power, and scheduling between multiple APs based on environmental information such as the location of the STA, interference between BSSs can be reduced.

[0007] This type of communication technology in which multiple APs operate in cooperation is called multi-AP communication, and the APs are classified into a single CoordinatorAP that manages all the APs, and CoordinatedAPs that operate under the management of the CoordinatorAP. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2018-50133 A Summary of the Invention [Problem to be solved by the invention]

[0009] As mentioned above, when multiple APs cooperate to communicate with a STA, it is necessary for each AP and STA to communicate with each other at an appropriate transmission power. If each AP or the STA connected to it transmits radio waves based on its own transmission power setting, radio interference may occur, causing a decrease in communication speed.

[0010] In view of the above problems, an object of the present invention is to provide a method that enables communication with an STA at appropriate transmission power even when multiple APs communicate with each other in a cooperative manner. [Means for solving the problem]

[0011] In order to achieve the above-mentioned object, a communication device according to one embodiment of the present invention is a communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, and has a communication means for performing data communication with a station in cooperation with an access point, wherein the communication means transmits a frame to the access point instructing the access point to communicate with the station, and the frame includes information that identifies the access point and information regarding the transmission power. Effect of the Invention

[0012] Even when multiple APs communicate with a STA in cooperation with each other, it is possible to ensure that the communication is carried out with appropriate transmission power. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing a network configuration according to the present invention. [Diagram 2] FIG. 2 is a diagram illustrating a hardware configuration of a communication device according to the present invention. [Diagram 3] FIG. 2 is a diagram showing a functional configuration of a communication device according to the present invention. [Figure 4] 2 is a flowchart showing the processing of the communication device 100 in the present invention. [Diagram 5] FIG. 2 is a flow chart showing the processing of communication devices 104 to 106 in the present invention. [Figure 6]2 is a sequence diagram showing data transmission between the communication device 100 and the communication devices 104 to 106 in the present invention. [Figure 7] 2 is a flowchart showing the processing of the communication device 100 in the present invention. [Figure 8] FIG. 2 is a flow chart showing the processing of communication devices 104 to 106 in the present invention. [Figure 9] 2 is a sequence diagram showing the processing of the communication device 100 and the communication devices 104 to 106 in the present invention. [Figure 10] 4 is a diagram illustrating an example of a trigger frame transmitted from the communication device 100 to the communication devices 104 to 106 in the first embodiment. [Figure 11] FIG. 11 is a diagram illustrating an example of a trigger frame transmitted from the communication device 100 to the communication devices 104 to 106 in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the configurations shown in the following embodiments are merely examples, and the present invention is not limited to the configurations shown in the drawings.

[0015] (Configuration of wireless communication system) 1 shows a configuration of a network in which a communication device 100 (hereinafter, AP100) according to the present embodiment participates. Communication devices 107 and 108 (hereinafter, STA107 and STA108) are stations (STAs) that play a role in participating in networks 101, 102, and 103. Communication device 109 (hereinafter, STA109) is an STA that plays a role in participating in networks 101 and 103. Communication device 104 (hereinafter, AP104) is an access point (AP) that plays a role in constructing wireless network 101, communication device 105 (hereinafter, AP105) is an AP that plays a role in constructing wireless network 102, and communication device 106 (hereinafter, AP106) is an AP that plays a role in constructing wireless network 103. AP100 functions as a Coordinator AP and can communicate with APs 104 to 106.

[0016] Each of the AP 100, APs 104 to 106, and STAs 107 to 109 is configured to be capable of communicating wireless frames that comply with the successor standard to the IEEE 802.11be standard, which targets a maximum transmission speed of 46.08 Gbps, and the successor standard, which targets a maximum transmission speed of 90 Gbps to over 100 Gbps. Note that IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers.

[0017] The main features of this successor standard to 802.11be are support for highly reliable and low latency communication and AP cooperation. In light of the above, in this embodiment, the successor standard to IEEE802.11be, which targets a maximum transmission speed of 90Gbps to 100Gbps, is also called IEEE802.11UHR (Ultra High Reliability). In addition, a wireless frame communicated under the successor standard is also called UHR PPDU. PPDU is an abbreviation for PLCP Protocol Data Unit, and PLCP is an abbreviation for Physical Layer Convergence Protocol.

[0018] The names IEEE802.11UHR and UHR standards are given for convenience in consideration of the goals to be achieved by the successor standards and the features that are the main features of the standards, and may be different names when the standards are completed. However, 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 and that can support the function of multiple APs cooperating to perform data communication with STAs.

[0019] Each communication device can communicate at frequencies of 2.4 Hz band, 3.6 GHz band, 5 GHz band, 6 GHz band, 45 GHz band, and 60 GHz band called millimeter wave. The frequency band used by each communication device is not limited to these, and a different frequency band such as the Sub 1 GHz band may be used. In addition, the AP 100, APs 104 to 106, and STAs 107 to 109 can communicate using bandwidths of 20 MHz, 40 MHz, 80 MHz, 160 MHz, 320 MHz, 540 MHz, 640 MHz, 1080 MHz, and 2160 MHz. The bandwidth used by each communication device is not limited to these, and a different bandwidth such as 240 MHz and 4 MHz may be used.

[0020] The AP 100, APs 104 to 106, and STAs 107 to 109 can realize multi-user (MU) communication, which multiplexes signals from multiple users, by performing OFDMA communication conforming to the IEEE802.11 standard. OFDMA stands for Orthogonal Frequency Division Multiple Access. In OFDMA communication, a portion of the divided frequency band (RU, Resource Unit) is assigned to each STA so that they do not overlap, and the carrier waves of each STA are orthogonal. Therefore, the AP can communicate with multiple STAs in parallel within a specified bandwidth.

[0021] Although each communication device is described as being compatible with the IEEE802.11UHR standard, it may also be compatible with a legacy standard that is a standard that precedes the IEEE802.11UHR standard. Specifically, each communication device may be compatible with at least one of the IEEE802.11a / b / g / n / ac / ax / be standards. In addition to the IEEE802.11 series standards, it may also be compatible with other communication standards such as Bluetooth (registered trademark), NFC, UWB, ZigBee, and MBOA. Note that 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, WiNET, and the like. It may also be compatible with a communication standard for wired communication such as wired LAN. Specific examples of the AP100 and APs 104 to 106 include, but are not limited to, wireless LAN routers and personal computers (PCs). The AP 100 and the APs 104 to 106 may be information processing devices such as wireless chips capable of performing wireless communication conforming to the IEEE802.11UHR standard. Specific examples of the STAs 107 to 109 include, but are not limited to, cameras, tablets, smartphones, PCs, mobile phones, video cameras, and headsets. The STAs 107 to 109 may be information processing devices such as wireless chips capable of performing wireless communication conforming to the IEEE802.11UHR standard. The wireless network in FIG. 1 is configured with four APs and three STAs, but the number and arrangement of the APs and STAs are not limited to this.

[0022] In this embodiment, when each of the APs 104 to 106 constructs multiple networks, the BSSIDs of the networks are all different. BSSID stands for Basic Service Set Identifier and is an identifier for identifying a network. Alternatively, the BSS Colors are all different. BSS Color stands for Basic Service Set color and is an ID for identifying a BSS that integrates multiple BSSIDs. Also, the SSIDs shown by the AP 100 and the APs 104 to 106 in each network are all common. SSID stands for Service Set Identifier and is an identifier for identifying an access point. In this embodiment, the communication device 100 and the APs 104 to 106 use one common SSID even when multiple connections are established.

[0023] The AP 100, the APs 104 to 106, and the STAs 107 to 109 may establish links via a plurality of frequency channels and perform multi-link communication for communication. An AP performing multi-link communication is also called an AP MLD (Multi-Link Device). For example, the AP 105 can establish a second link 111 in the 6 GHz band and communicate with the STA 107 in addition to a link 110 via a first frequency channel in the 5 GHz band. In this case, the STA 107 performs multi-link communication to maintain the second link 111 via the second frequency channel in parallel with the link 110 via the first frequency channel. In this way, the AP 105 and the AP 107 can improve the throughput in communication with the STA 107 by establishing links via a plurality of frequency channels with the STA 107.

[0024] In addition, in the multi-link communication, the links between the communication devices may establish a plurality of links with different frequency bands. For example, the STA107 may establish a third link with the AP105 in the 2.4GHz band in addition to the link 110 with the AP105 in the 5GHz band and the link 111 with the AP105 in the 6GHz band. Alternatively, the links may be established via a plurality of different channels included in the same frequency band. For example, the AP105 may establish a first link with 36ch with the AP105 in the 5GHz band, and in addition to this, the AP105 may establish a second link with 161ch with the AP105 in the 5GHz band. Note that links with the same frequency band and links with different frequency bands may be mixed. For example, the STA107 may establish a link with the AP105 in the 6GHz band with 2ch with the AP105 in addition to the link 110 with the AP105 in the 6GHz band with 35ch, and a link with the AP105 in the 2.4GHz band with 6ch. By establishing multiple connections with STA107 at different frequencies, AP105 can establish communication with STA107 in another band even if one band is congested, thereby preventing a decrease in throughput and communication delays in communication with STA107.

[0025] Each link is assigned a Link ID for each network in which the link is established. For example, consider the case where STA107 joins a 5 GHz network among the networks established by AP100, AP104 to AP106. If the link established with AP105 is designated as 110, a common Link ID of 1 is assigned to this link. Similarly, when STA107 joins a 6 GHz network and the link established here is designated as 111, a Link ID of 2 is assigned to this link. This value is merely an example, and different values ​​may be assigned to each established link or STA.

[0026] In the IEEE802.11 series of standards, the bandwidth of each frequency channel in the 2.4GHz, 5GHz, and 6GHz bands is defined as 20MHz. The bandwidth of each frequency channel in the 45GHz band is defined as 540MHz, and in the 60GHz band it is defined as 1080MHz or 2160MHz. Here, a frequency channel is a frequency channel defined in the IEEE802.11 series of standards, and multiple frequency channels are defined in each of the 2.4GHz, 5GHz, 6GHz, 45GHz, and 60GHz bands. Note that a single frequency channel may use a bandwidth of 40MHz or more by bonding with adjacent frequency channels.

[0027] (AP / STA configuration) 2 shows an example of the hardware configuration of the AP 100 in this embodiment. The AP 100 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. Note that the number of antennas may be multiple.

[0028] The storage unit 201 is composed of one or more memories such as a ROM and a RAM, and stores various information such as computer programs for performing various operations described below and communication parameters for wireless communication. ROM stands for Read Only Memory, and RAM stands for Random Access Memory. 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. Furthermore, the storage unit 201 may include multiple memories.

[0029] The control unit 202 is configured with one or more processors such as a CPU or MPU, and executes a computer program stored in the storage unit 201 to control the entire AP 100. The control unit 202 may control the entire AP 100 in cooperation with the computer program stored in the storage unit 201 and an OS (Operating System). The control unit 202 generates data and signals (wireless frames) to be transmitted in communication with other communication devices. The CPU stands for Central Processing Unit, and the MPU stands for Micro Processing Unit. The control unit 202 may include multiple processors such as multi-core processors, and the multiple processors may control the entire AP 100.

[0030] Furthermore, the control unit 202 controls the functional unit 203 to execute predetermined processes such as wireless communication, image capture, printing, and projection. The functional unit 203 is hardware for the AP 100 to execute predetermined processes. If the functional unit is a printer, it prints image data acquired via the communication unit 206. If the functional unit is a scanner, it transmits image data generated by scanning with the scanner to an external device via the communication unit 206. If the functional unit is a camera, it transmits image data captured by the camera to an external device via the communication unit 206.

[0031] The input unit 204 receives various operations from the user and is configured with, for example, a touch panel, hard keys, buttons, and the like.

[0032] The output unit 205 performs various outputs to the user via a monitor screen or a speaker. Here, the output by the output unit 205 may be a display on a monitor screen, a voice output by a speaker, a vibration output, or the like. Note that both the input unit 204 and the output unit 205 may be realized by one module, such as a touch panel. Also, the input unit 204 and the output unit 205 may be integrated with the AP 100, or may be separate from it.

[0033] The communication unit 206 controls wireless communication conforming to the IEEE802.11UHR standard. The communication unit 206 may also control wireless communication conforming to other IEEE802.11 series standards in addition to the IEEE802.11UHR standard, and control wired communication such as a wired LAN. The communication unit 206 controls the antenna 207 to transmit and receive signals generated by the control unit 202 for wireless communication.

[0034] If the AP 100 supports the NFC standard, Bluetooth standard, etc. in addition to the IEEE802.11UHR standard, the AP 100 may control wireless communication in accordance with these communication standards. If the AP 100 can perform wireless communication in accordance with multiple communication standards, the AP 100 may have a communication unit and an antenna that support each communication standard. The AP 100 communicates data such as image data, document data, and video data with each STA via the communication unit 206. The antenna 207 may be configured as a separate unit from the communication unit 206, or may be configured as a single module together with the communication unit 206.

[0035] The antenna 207 is an antenna capable of communication in the 2.4 GHz band, the 5 GHz band, the 6 GHz band, the 45 GHz band, and the 60 GHz band. In this embodiment, the AP 100 has two antennas, but it may have three antennas. Alternatively, it may have a different antenna for each frequency band. Furthermore, when the AP 100 has a plurality of antennas, it may have a communication unit 206 corresponding to each antenna.

[0036] The APs 104 to 106 and the STAs 107 to 109 have the same hardware configuration as the AP 100.

[0037] 3 is a block diagram showing the functional configuration of AP 100 in this embodiment. For example, this is a diagram showing the functional configuration realized by one or more processors executing programs stored in one or more memories. Note that APs 104 to 106 and STAs 107 to 109 also have the same configuration.

[0038] The AP 100 is made up of a MultiAP control unit 301 , a MultiAP communication setting UI unit 302 , a transmission power control unit 303 , a frame generation unit 305 , and a frame transmission / reception unit 306 .

[0039] The MultiAP control unit 301 is a functional unit that performs group formation processing for the AP 100 to cooperate with the other APs 104 to 106 in wireless communication, adds and deletes participating APs, and controls communication between APs.

[0040] The MultiAP communication setting UI (User Interface) unit 302 is a functional unit that provides a UI for the user to input settings for multi-AP communication of the AP 100 from the operation screen of the AP 100. Note that the AP 100 itself does not need to have this functional unit. For example, a server to which the AP 100 is connected or another AP may have this functional unit and display a UI for the user to input settings for the AP 100.

[0041] A transmission power control unit 303 manages the transmission power set by each AP during transmission when APs cooperate with each other in a group established by the MultiAP control unit 301, or manages the transmission power presented by other APs.

[0042] The frame generation unit 305 is a functional unit that generates frames for frame exchange when communicating with a connected STA or another AP.

[0043] The frame transmitting / receiving unit 306 transmits wireless frames including the probe request frame and data frame generated by the frame generating unit 305, and receives wireless frames from a partner device.

[0044] (Processing flow) Next, several embodiments will be described, including the flow of the processes executed by the AP / STA and sequences in the wireless communication system.

[0045] Example 1 In this embodiment, AP100 functions as a CoordinatorAP, which is an AP that is the main control of configuration, operation, and management when operating in cooperation with other APs. APs 104 to 106 function as CoordinatedAPs controlled by the CoordinatorAP, and communicate with STAs 107 to 109 according to instructions from AP100. The CoordinatorAP is sometimes called a SharingAP because it shares wireless medium resources with other APs and performs cooperative operations. Similarly, the CoordinatedAP is sometimes called a SharedAP.

[0046] In this embodiment, a case will be described in which data is transmitted from AP 100 to STA 107 via APs 104 and 105.

[0047] 4 is a flowchart showing an example of the process flow when APs 104 and 105 transmit data to STA 107 under the instruction of AP 100. Each process in the flowchart is executed by each functional unit shown in FIG. 3, and may be executed by multiple functional units in cooperation with each other.

[0048] This process starts when there is data to be transmitted from the AP 104 or AP 105 to the STA 107. Note that this flowchart may start when the AP 100 and the AP 104 or the AP 105 are connected, or when the AP 104, the AP 105 and the STA 107 are connected, and may start from S506 when the AP transmits data to the STA.

[0049] First, AP100 broadcasts a request to obtain information about nearby APs (S501). This request may include information indicating that a nearby AP having the same SSID will return a response if it receives the request. When AP100 receives a response to the request broadcast in S501 from the nearby AP (S502), it forms a group for cooperating with the nearby APs based on this (S503). Here, it is assumed that AP100 receives responses from APs 104 to 106 and forms a group with APs 104 to 106. The response information from the nearby AP may include information such as available channels, Multi-Link compatibility, BSSID information, radio wave strength (RSSI) of AP100 received by each CoordinatedAP, signal-to-noise ratio (SNR), IP address, MAC address, HT, VHT, HE, EHT, and UHR capability values, transmission speed of transmitted and received data, maximum allowable packet size, maximum number of connectable STAs, number of connected STAs, types of security standards supported by connected STAs or APs, channels used by connected STAs, data transmission and reception speeds including Min-Max, etc. Note that, although an example of wireless communication between APs is shown here, communication between APs may also be wired.

[0050] Next, the AP 100 transmits a request to the APs in the group formed in S503 to obtain information on the connected STAs (S504). Here, an identifier indicating a request for information on the connected STAs may be included. Next, the AP 100 receives information on the connected STAs from nearby APs as a response to the request transmitted in S504 (S505). The response information here may include information such as the MAC address of the STA, the channel and bandwidth used by the STA, the Multi-Link compatibility status, the signal strength (RSSI) or the signal-to-noise ratio (SNR) when communicating with each STA, the IP address, the presence or absence of the Power Save mode, the TIM value indicating the frequency of receiving Beacons, the values ​​of HT, VHT, HE, EHT, and UHR capability, the transmission speed of the transmitted and received data including Min-Max, the AID assigned by the AP to the STA, the maximum allowable packet size, and the type of security standard being connected.

[0051] Note that S501 and S504 may be performed simultaneously, and the reception processes of S502 and S505 may be performed simultaneously, or the processes of S504 and S505 may not be performed.

[0052] Next, AP100 transmits a frame to each CoordinatedAP (AP104-106) to confirm whether or not it can perform the next data transmission (S506). In other words, AP100 inquires whether or not the CoordinatedAP can participate in data transmission to the STA. The frame transmitted here may include information such as the amount of data and the time used for transmission. Next, AP100 receives a response from the CoordinatedAP to the frame transmitted in S506 (S507). The frame received at this time may include whether or not the CoordinatedAP can participate in data transmission and the conditions under which it can participate. The conditions for participation include designation of the channel and bandwidth that can be used for data transmission.

[0053] Based on the response received in S507, AP100 determines the Coordinated AP to be used for data transmission (S508). At this time, a frame may be transmitted to the Coordinated AP to inform it that it has been selected as the AP for data transmission. In this embodiment, AP104 and AP105 are assumed to participate in data transmission.

[0054] Next, AP100 determines the channel to be used by each CoordinatedAP (AP104, AP105) participating in data transmission. Furthermore, it determines the transmission power (Txpower) to be set when the CoordinatedAP transmits a frame (S509). In S509, it may also determine the transmission power of the Ack to be transmitted by the STA. Note that S508 and S509 may be performed simultaneously.

[0055] When the CoordinatedAPs participating in the data transmission and the transmission power of each CoordinatedAP are determined, the AP100 judges whether the CoordinatedAP can transmit data to the STA in this state (S510). The transmission power specified here may directly indicate the transmission power set by the CoordinatedAP, or may indicate the reception strength or reception sensitivity that the CoordinatedAP is expected to receive when the CoordinatedAP emits radio waves. When the CoordinatedAP is indicated with the reception strength or reception sensitivity, it calculates the power to be transmitted by itself so that the CoordinatedAP can receive radio waves with the indicated value, and transmits radio waves according to that value. For example, if there is no CoordinatedAP that can participate in the data transmission, the CoordinatedAP cannot transmit data to the STA, so the amount of data is changed or the conditions are changed, and the process is repeated from S506. In this case, the AP100 may be configured to transmit data directly to the STA only from the AP100. This judgment may be made by the AP100 based on the response from the CoordinatedAP in S507. Also, the process of S509 may be executed before S506 is executed, and the information of the determined transmission power may be included in the inquiry of S506. In this case, the response information transmitted by the Coordinated AP in S507 may be only information indicating whether or not participation is possible. This allows the Coordinator AP to immediately perform a new channel allocation, etc., and transmit a frame to the Coordinated AP again to confirm whether or not participation is possible.

[0056] When the data transmission is ready, the AP 100 transmits a trigger frame to the Coordinated AP instructing the Coordinated AP to transmit data to the STA (S512). In this embodiment, the trigger frame is transmitted from the AP 100 to the AP 104 and the AP 105. When transmitting data from the AP 100 to each STA, the data may be transmitted between S510 and S512.

[0057] An example of the trigger frame to be transmitted here is shown in FIG. 10. The fields / subfields shown here conform to the format defined in IEEE802.11ax. That is, from the beginning, it includes a Frame Control field 1301, a Duration field 1302, an RA field 1303, a TA field 1304, a Common Info field 1305 including information common to multiple devices, a User Info field 1306 including information on each of the multiple devices, a Padding field 1307, and an FCS field 1308. A 4-bit Trigger Type subfield 1309 in the Common Info field 1305 specifies the type of trigger by the trigger frame. Also, a Length subfield 1310 in the Common Info field 1305 indicates a communication period common to all Coordinated APs. The communication period corresponds to the amount of data that each Coordinated AP can transmit and receive. Table 1 shows an example of the correspondence between the Trigger type subfield value and the type of trigger.

[0058] [Table 1]

[0059] When the Trigger type subfield value is 9, it indicates that the trigger frame instructs multi-AP data transmission in which multiple APs communicate data in cooperation with each other.

[0060] The User Info field 1306 corresponds to each CoordinatedAP, and the same number of User Info fields 1306 are linked and transmitted as the number of CoordinatedAPs. The User Info field 1306 includes a BSS Color field 1311 for setting the value of BSS Color, and a Txpower field 1312 for setting the value of Txpower. The value set in the 1311 field is not limited to the BSS Color value, and may be any value that can identify the AP, such as the BSSID. The value given in the field 1311 allows the CoordinatedAP to specify which CoordinatedAP the data is for. The size is 6 bits for BSS Color and 6 bytes for BSSID. The Txpower field 1312 inputs the transmission power value to be set by each CoordinatedAP. The size is 1 byte. The CoordinatedAP checks the BSS Color and Txpower, and transmits data according to the Txpower assigned to it. For example, in the first User Info field 1306, the AP 100 sets the value of the BSS Color of the AP 104 in the 1311 field, includes information for the AP 104 in the fields following the 1311 field, and further sets the value of the BSS Color of the AP 105 in the second User Info field 1306, includes information for the AP 105 in the fields following the 1311 field, thereby making it possible to notify the APs 104 and 105 of information such as transmission power. In addition to Txpower, the User Info field 1306 may include information on RU allocation and information on MCS (modulation and coding scheme) indicating the modulation and coding method. Here, the Coordinated AP determines the transmission power based on the value included in the Txpower field 1312, but the Coordinated AP may also determine the transmission power based on values ​​included in fields other than the Txpower field 1312.

[0061] Returning to the explanation of FIG. 4, in S512, AP100 sets the Trigger type subfield value to 9, and generates and transmits a UHR PPDU including a trigger frame for data communication in cooperation with multiple APs, i.e., data transmission in Multi-AP. AP100 judges whether or not the CoordinatedAP, which was instructed to transmit data by the trigger frame transmitted in S512, has received a notification from the CoordinatedAP indicating whether or not it was able to transmit data to the STA (S513). If there is a CoordinatedAP that was unable to transmit data correctly, AP100 does not receive the notification in S513, and returns to S506 to select an AP again. If the notification is received in S513, AP100 transmits a frame to the CoordinatedAP to confirm whether or not the data was correctly transmitted to the STA (S514). AP100 confirms whether or not the CoordinatedAP has received all the Acks for the data transmitted from the CoordinatedAP to the STA from the frame returned from the CoordinatedAP as a response to this confirmation (S515). If the CoordinatedAP has received the Ack normally, proceed to S516; if not, return to S506. The Ack confirmed here is for the data that was successfully sent from the CoordinatedAP to the target STA. This makes it possible to determine which data was successfully delivered to the STA. Note that the processes from S513 to S515 do not necessarily have to be performed.

[0062] The AP 100 checks whether each AP in the group has data to transmit (S516). If there is still data to transmit, the process is restarted from S506. If not, the process is terminated. When restarting the process, the process may start from S508.

[0063] Fig. 5 is a flowchart showing an example of the flow when AP104 and AP105 cooperate to transmit data to STA107 and STA108, respectively. Note that the information to be included in the frame overlaps with the explanation of Fig. 4, so it will be omitted. Each process in the flowchart is executed by each functional unit shown in Fig. 3, and may be executed by multiple functional units in cooperation.

[0064] The process of this flowchart starts when a request to obtain information about nearby APs (S501) is received from the AP 100.

[0065] First, AP104 and AP105 receive a request from AP100 to obtain information about nearby APs (S601). AP104 and AP105 transmit a response to the AP information obtainment request (S602). The information to be included here has been described in the explanation of FIG. 4 and will not be described here. Next, AP104 and AP105 receive a request from AP100 to obtain information about connected STAs (S603). In response, AP104 and AP105 transmit a response including information about the currently connected STAs (S604). The information to be included here has been described in the explanation of FIG. 4 and will not be described here.

[0066] Next, the AP104 and AP105 receive from the AP100 a request to inquire whether there is data to be transmitted from the AP104 and AP105 to the STA107 and STA108, that is, the inquiry of S506 (S605). Note that the amount of data queue may be presented in S605. Upon receiving this request, the AP104 and AP105, i.e., the Coordinated AP, decide whether to participate in data transmission based on the current communication situation (S606). For example, if there is no data to transmit, a response indicating non-participation is transmitted with REASON=NOQUEUE (S607). Note that in the case of non-participation, no response may be transmitted. If participating in data communication in S606, the AP104 and AP105 transmit a response indicating participation or conditional participation to the AP100 (S608). Then, a trigger frame indicating the timing of transmitting data from the AP100 to the STA107 and STA108 is received (S610). Note that when transmitting data from the AP100 to each STA, transmission data may be received in advance. The trigger frame contains the BSS Color and transmission power used by the AP 104 and the AP 105. Therefore, the AP 104 and the AP 105 have their own allocations and can determine the transmission power that should be set.

[0067] Immediately after receiving the trigger frame, the AP104 and AP105 check whether or not the frame can be transmitted (S611). For example, the transmission power specified by the trigger frame may exceed the maximum transmission power of the AP, or the TXOP cannot be secured. If the frame cannot be transmitted, the AP notifies the CoordinatorAP of failure as the REASON (S612). If it is determined in S611 that the frame can be transmitted, the AP104 and AP105 transmit data to the STA at the specified transmission power (S613). Specifically, the AP104 and AP105 obtain information on the transmission power included in the Txpower field 1312 of the trigger frame received in S610, decides the transmission power based on the obtained information, and transmits data to the STA (STA107 and STA108 in this case). The AP104 and AP105 may be configured to determine the MCS according to the transmission power indicated by the trigger frame received in S610 and transmit data to the STA. For example, if the transmission power indicated by the trigger frame is low, the MCS is appropriately lowered to transmit data to the STA. If the data transmission to the STA (S613) is successful, the process waits for an Ack sent from the STA (S614).

[0068] If an Ack is returned in S614, AP104 and AP105 transmit a success notification to the Coordinator AP (S615, S616). Then, the process ends. If data is to be transmitted next, the process may be restarted from S605 or S610. If an Ack is not returned in S614, AP104 and AP105 return to the process of S605. Alternatively, the process may end by notifying AP100 of an error.

[0069] FIG. 6 shows a sequence diagram of how AP104 and AP105, which are Coordinated APs, transmit data to STA107 and STA108 under the instruction of AP100, which is the Coordinator AP.

[0070] This sequence diagram starts from S506 in FIG. 4 and S605 in FIG. 5. First, AP100 transmits a frame to AP104 and AP105 asking whether they can participate in data transmission (S701). In response, AP104 and AP105, which are Coordinated APs, return a response to AP100 (S702). This response includes information on whether they can participate in data transmission. If they can participate, it may include information such as available channels and link information, maximum transmission power, BSS Color, whether there is transmission data, the amount of transmission data, and the type of access category. If they can participate, it includes information on available channels and links. If they cannot participate, it may include the reason why they cannot participate. Examples of reasons why they cannot participate include BUSY and DISCONNECTED. Based on this response, AP100 selects APs to participate in data transmission. Here, it is AP104 and AP105, which are Coordinated APs, that participate in data transmission.

[0071] When data transmission is ready, AP100 transmits a trigger frame indicating the timing of data transmission to AP104 and AP105 (S704). In response to this, AP104 and AP105 transmit data to STA107 and STA108, respectively (S705). STA107 and STA108 return Ack in response to the received data (S706). If the data is transmitted correctly, AP104 and AP105 return a frame indicating successful data transmission to AP100 (S707). If AP104 and AP105 have not received all Acks or if time has passed, a message is sent from AP100 to AP104 and AP105 to confirm whether all data has been received (S708). When AP104 and AP105 receive this message, they return Ack indicating the current reception status (S709). AP104 and AP105 may also notify AP100 of a transmission failure notification at the timing of transmitting S707. Also, steps S707 to S709 do not have to be performed.

[0072] In this way, AP104 and AP105 can communicate with the STA at the appropriate transmission power instructed by AP100. The data is not limited to data transmitted from AP104 and AP105, and the data itself to be transmitted from AP100 to the STA by AP104 and AP105 may be instructed. In this embodiment, AP100 transmits the trigger frame to AP104 and AP105 as a radio wave, but this may be done by wire. Similarly, in FIG. 4, all data communicated between AP100 and AP104 and AP105 may be done by wire. Also, according to FIG. 1, AP100 and AP106 are connected by wire, and AP100 and AP104 are connected by wireless. AP100 may transmit data to STA107 and STA109 as Coordinated APs in the same manner as in this embodiment.

[0073] The SSID and BSSID of AP100, AP104, AP105, and AP106 that operate in cooperation with each other may be the same or different. However, if the BSSID is the same, IDs for identifying AP100, AP104 to AP106 are prepared separately. In this case, the CoordinatorAP uniquely manages IDs for identifying each AP to be coordinated in advance. The CoordinatedAP also acquires the ID in advance and stores it as its own ID, so that it can identify that the ID is addressed to itself. In this embodiment, multiple links 110 and links 111 may be simultaneously established between AP105 and STA107.

[0074] In this way, AP 104 and AP 105 adjust the transmission power in cooperation with each other, and are able to transmit data to STA 107 and STA 108 simultaneously.

[0075] Example 2 In the second embodiment, the configuration in which the CoordinatedAP transmits data to the STA based on an instruction from the CoordinatorAP has been described. In this embodiment, the configuration in which the CoordinatedAP receives data from the STA based on an instruction from the CoordinatorAP will be described.

[0076] In this embodiment, AP 100 functions as a Coordinator AP. APs 104 and 106 function as Coordinated APs and communicate with STAs 107 and 109 under instructions from AP 100. In this embodiment, a case will be described in which APs 104 and 106 receive data from STAs 107 and 109 under instructions from AP 100. The basic configuration of this embodiment is the same as that of embodiment 1, so only the differences will be shown.

[0077] FIG. 7 is a flowchart showing an example of the process flow of the CoordinatorAP when a STA transmits data to each AP.

[0078] This process starts when the STA107 and STA109 have data to transmit to the AP104 and AP106. Note that this flowchart may start when the AP100 and the AP104 and the AP106 are connected, when the AP104 and the STA107 are connected, and when the AP106 and the STA109 are connected, and when data is received, it may start from S806. Also, explanations of parts that overlap with the first embodiment will be omitted.

[0079] S801 to S805 are the same as S501 to S505 in the first embodiment, so the description will be omitted. The AP 100 transmits a frame inquiring whether each Coordinated AP can receive the next data (S806). This frame may include information such as the amount of data and the time used for transmission. In addition, when the Coordinator AP assigns an AID to the STA, information linking the MAC address of the STA with the ID assigned by the Coordinator AP may be transmitted to the Coordinated AP. Next, the AP 100 receives a response from the Coordinated AP to the inquiry of S806 (S807). The response from the Coordinated AP may include whether the Coordinated AP will participate in data reception and the conditions for participation. The conditions for participation include the channel and bandwidth that can be used for data transmission, and the maximum transmission power that the STA can output. Alternatively, the SNR of each Coordinated AP acquired by the STA may be included. In addition, the amount of data to be received in the future and the amount of data for each type of access category received from the STA connected to each Coordinated AP may be included. The amount of data sent is determined for each AID or STA MAC address.

[0080] Based on the response information received from each Coordinated AP in S807, AP100 determines which Coordinated AP to use for data reception (S808). At this time, a frame may be sent to the Coordinated AP to inform it that it has been selected as the AP for data reception. In this embodiment, AP104 and AP106 are assumed to participate in data reception.

[0081] Next, the AP 100 determines the transmission power of the STA when each Coordinated AP (AP 104, AP 106) receives data (S809). Note that the transmission power when the Coordinated AP transmits a trigger frame or Ack may be determined here. S808 and S809 may be performed simultaneously.

[0082] Once the CoordinatedAPs participating in data reception and the channels and RUs used by each CoordinatedAP are determined, the AP100 judges whether data reception is possible in that state (S810). For example, if there is no CoordinatedAP that can participate, the CoordinatedAP cannot receive data from the STA, so it changes the amount of data or changes the conditions and starts over from S806. In this case, data may be received directly from the STA using only the AP100. The judgment in S810 may be made based on a reply from the CoordinatedAP in S807. Also, the processing in S809 may be performed before the processing in S806 is performed. In this case, the information transmitted by the CoordinatedAP in S807 may be only whether or not it is possible to participate. This allows the CoordinatorAP to immediately change the transmission power to be used and transmit a frame to the CoordinatedAP again to confirm whether or not it is possible to participate.

[0083] If it is determined in S810 that data can be received, a trigger frame for transmitting data from the STA to the Coordinated AP is transmitted (S811). This trigger frame is transmitted from the Coordinator AP to the Coordinated AP. In this embodiment, it is transmitted from AP 100 to AP 104 and AP 106.

[0084] The trigger frame transmitted here is as shown in Fig. 11. Fields 1301 to 1310 are omitted because they are the same as those in Fig. 10. However, when the Trigger type subfield value is 10, this indicates that the trigger frame instructs data reception in Multi-AP.

[0085] In this embodiment, the User Info field 1306 is provided with a BSSID field 1411, an AID field 1412, and a UL Target Receive Power field 1413. The BSSID field 1411 indicates the BSSID of the Coordinated AP. Since the BSSID field 1411 has 6 bytes, it may be a field indicating the BSS Color as in the first embodiment. In this case, the size is 6 bits. Also, since it is sufficient to identify the AP, a unique ID assigned by the Coordinator AP may be used.

[0086] The AID field 1412 indicates an AID (Association ID) that the AP assigns when connecting to the STA. Table 2 shows the values ​​of the AID field 1412 and their meanings.

[0087] [Table 2]

[0088] In this embodiment, the AID field 1412 uses the AID assigned by the Coordinated AP to the STA to which it connects. The Coordinator AP may assign an AID to each STA. For example, the Coordinator AP may assign an AID to each STA based on the information of the STA acquired from each Coordinated AP in S802. If the value of the AID field is 1-2007, it will be the value of the assigned AID.

[0089] The UL Target Receive Power field 1413 indicates the transmission power of the STA desired by the AP. Note that this definition complies with the definition of the field included in the Trigger frame of IEEE802.11. Here, it is assumed that the reception strength and reception sensitivity at which the CoordinatedAP receives radio waves when the STA transmits radio waves are specified. The STA calculates the transmission power so that the AP to which it is connected can receive radio waves at the specified reception strength and reception sensitivity, and transmits radio waves based on the calculation result. Note that the specified value may be the transmission power itself that the STA transmits.

[0090] Also, if the Coordinator AP allocates AIDs and can assign different AIDs to each STA even if they are connected to different APs, the trigger frame transmitted from the Coordinator AP to the Coordinated AP may be a Basic trigger frame with Type = 0. The STA identified by the AID field 1412 will determine the transmission power based on the value contained in the corresponding 1413 field and transmit data.

[0091] Returning to the explanation of FIG. 7, if the CoordinatedAP can receive data from the STA according to the trigger frame transmitted in S811, the CoordinatedAP receives a notification of successful data reception from the CoordinatedAP (S812). This notification only needs to include information on whether data reception was successful. This notification may also be sent only when data reception fails. This notification may include the amount of data stored in the queue by the STA as information for each type of access category. Information on whether the CoordinatedAP holds more data to be transmitted by the STA may be confirmed by the trigger frame and the frame transmitted from the STA to the CoordinatedAP accompanying the trigger frame. In this way, the CoordinatedAP may be configured to check whether there is still data to be transmitted in the STA and notify the CoordinatedAP of the confirmation result. The CoordinatedAP checks whether there is still data to be transmitted from the STA by any method (S816), and ends the process if there is no data to be transmitted from the STA. If there is data to be transmitted from the STA, the process may start again from S806 or S808.

[0092] 8 is a flowchart showing an example of the flow when the AP 104 and the AP 106 cooperate to receive data from the STA 107 and the STA 109. Note that the information included in the frame is omitted because it overlaps with the explanation of FIG.

[0093] This process starts when a request to obtain information on nearby APs is received from the AP 100. S901 to S904 are the same as in FIG. 5, so the description will be omitted. The AP 104 and AP 106 receive a request from the AP 100 asking whether they will participate in data reception in preparation for receiving data from the STAs 107 and 109 (S905). Note that before this request, the STAs 107 and 109 may inquire of the STAs connected to their own devices about the amount of data to be transmitted that is stored in the queue, and grasp the amount of data that the STAs should transmit. In this case, it is desirable to grasp the amount of data for each type of access category. When a request to participate is received from the Coordinator AP, the Coordinated AP determines whether to participate in data reception based on the current communication status and the amount of data from the STA (S906). For example, if there is no data to be received from the STA, a response indicating that the STA will not participate is transmitted with REASON=NOQUEUE (S907).

[0094] If the STA decides to join in S906, the AP 104 or 106 transmits a response to the AP 100 including the channel that the STA can join, the link number, the maximum transmission power that the STA can set, and the SNR acquired by the STA for the surrounding APs (S908). The AP 104 or 106 then notifies the AP 100 that it will participate in data reception (S908), and if it is selected as the AP that will receive data from the AP 100, it receives a trigger frame from the AP 100 indicating the timing of receiving data from the STAs 107 or 109 (S909). The trigger frame received at this time is as shown in FIG. 11. From the information included in this trigger frame, the AP 104 or 106 can determine the transmission power of the STA that it specifies. The AP 104 or 106 analyzes the link number, RU, and transmission power assigned in the trigger frame received from the AP 100 (S910). For example, if Link ID=1, RU=2, and expected received power=-80 dBm, the STA adjusts the transmission power so that Link ID is 1, RU number is 2, and the received power of the Coordinated AP is -80 dBm. The RU and transmission power may be specified in S911, not in S909. If the transmission power in the trigger frame or Ack transmitted by the AP is specified, S911 and S914 are performed according to that value.

[0095] After analyzing the trigger frame received from the CoordinatorAP, the AP104 and AP106 notify the STA of the instructed contents (link number, RU, transmission power, etc.) as is (S911). A trigger frame is used for this notification. For example, the trigger frame notifies the STA of information regarding transmission power based on the value included in field 1413 for the STA specified in AID field 1412. The AP104 and AP106 receive data from the STA based on the information in the trigger frame sent in S911 (S912). In other words, the STA transmits data to the CoordinatedAP at the transmission power specified by the CoordinatorAP. If the data cannot be received correctly from the STA, the AP104 and AP106 transmit the data including the reason (REASON) indicating the data reception failure to the CoordinatorAP (S913). Then, the process returns to S905.

[0096] If data reception from the STA is successful in S912, the AP104 and AP106 send an Ack (S914) and send a data reception success notification to the CoordinatorAP (S915). In S915, the AP104 and AP106 may send the amount of data that each STA connected to the AP104 and AP106 has in its queue to send. Alternatively, the AP104 and AP106 may inquire about the amount of data accumulated in each STA and send the response to the CoordinatorAP. The AP104 and AP106 may also transfer the data received from the STA in S912 to the CoordinatorAP.

[0097] FIG. 9 shows a sequence in which AP 100, which is a Coordinator AP, instructs APs 104 and 106, which are Coordinated APs, to receive data from STAs 107 and 109.

[0098] This sequence starts from S806 in FIG. 7 and S905 in FIG. 8. First, the AP 100 transmits a frame to the APs 104 and 106 asking whether they can participate in data reception (S1001). In response, the APs 104 and 106, which are Coordinated APs, return a response (S1002). This response includes information on whether or not to participate in data reception. If participation is possible, information on the channels in which participation can be made, the maximum transmission power of the link, AP, and STA, and the amount of data that the STA has accumulated for each type of access category and is scheduled to transmit is included. If participation is not possible, the reason for not being able to participate may be included. Examples of reasons for not being able to participate include BUSY and DISCONNECTED. Based on this response, the AP 100 selects an AP to participate in data reception, and transmits a frame that serves as a trigger for receiving data from the STA to the selected AP (S1003). The APs 104 and 106 that receive the trigger frame interpret the contents of the frame and determine the transmission power allocated to themselves and the STAs that they connect to. Based on this, they transmit a trigger frame for receiving data from the STA (S1004). Upon receiving the trigger frame, STA107 and STA109 transmit data at a transmission power based on the information in the trigger frame (S1005). AP104 and AP106 return an Ack associated with the received data (S1006). If all data is received from STA107 and AP109, AP104 and AP106 first transmit a frame to AP100 indicating that data reception is complete (S1007). AP100 returns an Ack to the reception completion notification (S1009).

[0099] In this way, AP104 and AP106 can specify appropriate transmission power to the STAs based on instructions from AP100, and receive data from the STAs. Note that data may also be transmitted from STA107 to AP100, for example. On the other hand, for example, AP104 may forward data received from STA107 to AP100, and AP106 may process data received from STA109 by itself. In this case, in FIG. 9, the received data is forwarded from AP104 to AP100 along with S1007.

[0100] In this embodiment, the AP100 and the AP104 are connected by radio waves, and the AP100 and the AP106 are connected by wires, but both may be wireless or both may be wired. The SSID and BSSID of the AP100, the AP104, the AP105, and the AP106 that operate in cooperation may be the same or different. However, if the BSSID is the same, a separate ID is required to identify the AP100, the AP104 to the AP106. In this case, the CoordinatorAP uniquely manages in advance an ID that identifies each AP to be coordinated. The CoordinatedAP also acquires the ID in advance and stores it as its own ID, so that it can identify that the ID is addressed to itself.

[0101] According to this embodiment, the AP 105 and the AP 106 can receive data from the STA 107 and the STA 109, respectively, with appropriate transmission power.

[0102] (Other embodiments) A configuration may be adopted that combines the above-described first and second embodiments. In other words, a configuration may be adopted in which the Coordinated AP transmits data to a STA based on an instruction from the Coordinator AP, and a configuration in which the Coordinated AP receives data from a STA based on an instruction from the Coordinator AP can both be implemented.

[0103] In this embodiment, for the sake of simplicity, only Ack is handled, but other types of Ack, such as BlockAck and Multi-STA BlockAck, are also included.

[0104] In this embodiment, the AP 100 that is the Coordinator AP does not directly communicate with the STAs, but the AP 100 that is the Coordinator AP may also simultaneously take on the role of a Coordinated AP.

[0105] A recording medium on which the program code of the software for realizing the above-mentioned functions is recorded may be supplied to the system or device, and the computer (CPU, MPU) of the system or device may read and execute the program code stored in the recording medium. In this case, the program code itself read from the storage medium will realize the functions of the above-mentioned embodiments, and the storage medium on which the program code is stored will constitute the above-mentioned device.

[0106] Examples of storage media for supplying the program code include flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memory cards, ROMs, and DVDs.

[0107] In addition, the above-mentioned functions may be realized not only by the computer executing the read program code, but also by the OS running on the computer performing all or part of the actual processing based on the instructions of the program code. OS is an abbreviation for Operating System.

[0108] Furthermore, the program code read from the storage medium may be written to a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, and a CPU provided in the function expansion board or function expansion unit may perform part or all of the actual processing based on instructions in the program code to realize the above-mentioned functions.

[0109] 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.

[0110] The disclosure of this embodiment includes the following configurations, methods, and programs.

[0111] (Configuration 1) A communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, A communication device comprising: a communication means for performing data communication with a station in cooperation with an access point; the communication means transmitting a frame to the access point instructing the access point to communicate with the station; the frame including information for identifying the access point and information regarding transmission power.

[0112] (Configuration 2) 2. The communication device according to configuration 1, wherein the information for identifying the access point is a value indicating a BSS Color.

[0113] (Configuration 3) 2. The communication device according to claim 1, wherein the information for identifying the access point is a BSSID.

[0114] (Configuration 4) 4. The communication device according to claim 1, wherein the information relating to transmission power is a value of transmission power that the access point should use in transmitting data to the station device.

[0115] (Configuration 5) The communication device described in any one of configurations 1 to 3, characterized in that the information regarding the transmission power is a value based on an expected reception strength that the communication device will receive when the access point emits radio waves.

[0116] (Configuration 6) The communication device according to any one of configurations 1 to 5, characterized in that the access point transmits a frame to the station device instructing the station to transmit data to the access point based on the frame.

[0117] (Configuration 7) 7. The communication device according to configuration 6, wherein the information regarding the transmission power is a value of the transmission power that the station device should use for transmitting data to the access point.

[0118] (Configuration 8) A communication device according to any one of configurations 1 to 7, characterized in that an access point that performs data communication with a station is selected from a plurality of access points, and the frame includes information for identifying the selected access point and information regarding the transmission power corresponding to the access point, each of which is equal to the number of selected access points.

[0119] (Configuration 9) The communication device according to any one of configurations 1 to 8, characterized in that the communication device is an access point device, the frame is a trigger frame, and information for identifying the access point and information regarding transmission power are included in a User Info field of the trigger frame.

[0120] (Configuration 10) A communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, A communication device comprising a communication means for performing data communication with a station in cooperation with an access point, the communication means receiving a frame from the access point instructing the communication device to communicate with a station, the frame including information for identifying the communication device and information regarding transmission power.

[0121] (Configuration 11) 11. The communication device according to claim 10, wherein the information for identifying the communication device is a value indicating a BSS Color.

[0122] (Configuration 12) 11. The communication device according to claim 10, wherein the information for identifying the communication device is a BSSID.

[0123] (Configuration 13) 13. The communication device according to any one of configurations 10 to 12, wherein the information relating to transmission power is a value of transmission power that the communication device should use for transmitting data to the station.

[0124] (Configuration 14) A communication device described in any one of configurations 10 to 12, characterized in that the information regarding the transmission power is a value based on the expected reception strength received by the access point when the communication device emits radio waves.

[0125] (Configuration 15) The communication device according to any one of configurations 10 to 14, characterized in that the communication device transmits a frame to the station device instructing the station to transmit data to the communication device based on the frame.

[0126] (Configuration 16) 16. The communication device according to configuration 15, wherein the information regarding the transmission power is a value of the transmission power that the station device should use for transmitting data to the communication device.

[0127] (Configuration 17) A communication device according to any one of configurations 10 to 16, characterized in that the frame includes information for identifying a selected access point and information regarding the transmission power corresponding to the access point, each of which is equal to the number of selected access points.

[0128] (Configuration 18) The communication device according to any one of configurations 10 to 17, characterized in that the communication device is an access point device, the frame is a trigger frame, and information for identifying the access point and information regarding transmission power are included in a User Info field of the trigger frame.

[0129] (Method 1) A control method executed by a communication device that performs wireless communication conforming to the IEEE 802.11 series standard, comprising: A control method comprising a communication step of performing data communication with a station in cooperation with an access point, the communication step including transmitting a frame to the access point instructing the access point to communicate with the station, the frame including information for identifying the access point and information regarding transmission power.

[0130] (Method 2) A control method executed by a communication device that performs wireless communication conforming to the IEEE 802.11 series standard, comprising: A control method comprising a communication step of performing data communication with a station in cooperation with an access point, wherein in the communication step, the communication device receives a frame from the access point instructing the communication device to communicate with the station, the frame including information for identifying the communication device and information regarding transmission power.

[0131] (program) A program for causing a computer to function as the communication device according to any one of configurations 1 to 18. [Explanation of symbols]

[0132] 201 Storage section 202 Control section 203 Functional Department 204 Input section 205 Output section 206 Communications Department

Claims

1. A communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, A communication device comprising a communication means for performing data communication with a station in cooperation with an access point, the communication means transmitting a trigger frame to the access point, the trigger frame including information for identifying the access point and information regarding transmission power.

2. 2. The communication device according to claim 1, wherein the information for identifying the access point is a value indicating a BSS Color.

3. 2. The communication device according to claim 1, wherein the information for identifying the access point is a BSSID.

4. 2. The communication device according to claim 1, wherein the information about transmission power is a value of transmission power that the access point should use for transmitting data to the station device.

5. 2. The communication device according to claim 1, wherein the information about the transmission power is a value based on an assumed reception strength of radio waves emitted by the access point and received by the communication device.

6. 2. The communication device according to claim 1, wherein the access point transmits to the station device a frame instructing the station to transmit data to the access point based on the trigger frame.

7. 7. The communication device according to claim 6, wherein the information about transmission power is a value of transmission power that the station device should use to transmit data to the access point.

8. 2. The communication device according to claim 1, wherein an access point for performing data communication with a station is selected from among a plurality of access points, and the trigger frame includes information for identifying the selected access point and information regarding the transmission power corresponding to the access point, each of which is equal to the number of selected access points.

9. 2. The communication device according to claim 1, wherein the communication device is an access point device, and the information for identifying the access point and the information regarding transmission power are included in a User Info field of the trigger frame.

10. A communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, A communication device comprising a communication means for performing data communication with a station in cooperation with an access point, the communication means receiving a trigger frame from the access point, the trigger frame including information for identifying the communication device and information regarding transmission power.

11. The communication device according to claim 10, wherein the information for identifying the communication device is a value indicating a BSS Color.

12. 11. The communication device according to claim 10, wherein the information for identifying the communication device is a BSSID.

13. 11. The communication device according to claim 10, wherein the information about the transmission power is a value of the transmission power that the communication device should use for transmitting data to the station.

14. 11. The communication device according to claim 10, wherein the information about the transmission power is a value based on an assumed reception strength of radio waves emitted by the communication device and received by the access point.

15. The communication device according to claim 10, wherein the communication device transmits to the station device a frame instructing the station to transmit data to the communication device based on the trigger frame.

16. 16. The communication device according to claim 15, wherein the information about transmission power is a value of transmission power that the station device should use to transmit data to the communication device.

17. The communication device according to claim 10, characterized in that the trigger frame includes information for identifying a selected access point and information regarding the transmission power corresponding to the access point, each of which is equal to the number of selected access points.

18. The communication device according to claim 10, wherein the communication device is an access point device, and the information for identifying the access point and the information regarding transmission power are included in a User Info field of the trigger frame.

19. A control method executed by a communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, comprising: A control method comprising a communication step of performing data communication with a station in cooperation with an access point, wherein the communication step transmits a trigger frame to the access point, the trigger frame including information for identifying the access point and information regarding transmission power.

20. A control method executed by a communication device that performs wireless communication in accordance with the IEEE 802.11 series standard, comprising: A control method comprising a communication step of performing data communication with a station in cooperation with an access point, wherein the communication step receives a trigger frame from the access point, the trigger frame including information for identifying the communication device and information regarding transmission power.

21. A program for causing a computer to function as the communication device according to any one of claims 1 to 18.

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