Access point, and method for controlling coordinated communication

Abstract

This access point comprises a transceiver unit that transmits and receives information relating to reconfiguration of coordinated communication, and a control unit that reconfigures coordinated communication according to the received information relating to reconfiguration of coordinated communication.

Description

Access point and method for controlling cooperative communication

[0001] The present disclosure relates to an access point and a method for controlling cooperative communication.

[0002] The technical specifications for 802.11be (hereinafter referred to as "11be") are currently being developed as the successor to the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard, 802.11ax (hereinafter referred to as "11ax"). 11ax is also known as High Efficiency (HE), and 11be is also known as Extreme High Throughput (EHT). The successor to 11be is sometimes called Ultra High Reliability (UHR), and discussions on the required specifications are currently underway.

[0003] IEEE 802.11-19 / 1961r1, Multi-AP Group EstablishmentIEEE 802.11-19 / 0103r1, AP Coordination in EHTIEEE Std 802.11-2020, December 2020

[0004] For 11be and UHR, the application of Multi-AP coordination (hereinafter referred to as "cooperative communication") is being considered, in which access points (also called "base stations", hereinafter referred to as "APs (Access Points)") cooperate to send and receive data between each terminal (also called non-AP STAs (Station), hereinafter referred to as "STAs").

[0005] However, there is no consideration of the reconfiguration procedure for the multi-AP control target, for example, when an AP or STA is stopped or stops data transmission, or when the target of cooperative communication changes or cooperative communication becomes unnecessary due to a decrease in interference from APs and STAs performing cooperative communication, etc. Furthermore, there is no consideration of the control of APs performing cooperative communication for each cooperative method.

[0006] Non-limiting examples of the present disclosure contribute to providing a reconfiguration procedure for a Multi-AP control target.

[0007] An access point according to one embodiment of the present disclosure includes a transceiver unit that transmits and receives information regarding the reconfiguration of cooperative communication, and a control unit that performs the reconfiguration of cooperative communication in accordance with the received information regarding the reconfiguration of cooperative communication.

[0008] These comprehensive or specific aspects may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a recording medium, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0009] According to the present invention, it is possible to provide a wireless communication device and a communication method for controlling cooperative communication.

[0010] Further advantages and benefits of an embodiment of the present disclosure will become apparent from the specification and drawings. Such advantages and / or benefits may be provided by some of the embodiments and features described in the specification and drawings, respectively, but not necessarily all of them may be provided to obtain one or more identical features.

[0011] Diagram showing the Element formatDiagram showing the Element ID tableDiagram showing an example of the STA configurationDiagram showing an example of the AP configurationDiagram showing an example of the AP and STA placementDiagram showing the overall stepsDiagram showing another example of AP placementDiagram showing an example of the Coordination Group list notification formatDiagram showing an example of the update notification formatDiagram showing the operation sequenceDiagram showing yet another example of AP placementDiagram showing the operation sequenceDiagram showing an example of the interference measurement request formatDiagram showing an example of the interference measurement report formatDiagram showing yet another example of AP placementDiagram showing an example of the cooperative communication group list notification format

[0012] <About Multi-AP Coordination> A method has been proposed in which APs (also called Coordination Group, Coordination set, multi-AP group, or AP candidate set) that control cooperative communication are defined as a configuration of cooperative communication, and APs included in the target APs of cooperative communication perform cooperative communication (see Non-Patent Document 1).

[0013] On the other hand, as cooperative communication methods, C-OFDMA (Coordinated Orthogonal Frequency Division Multiple Access), C-TDMA (Coordinated Time Division Multiple Access), C-SR (Coordinated Spatial Reuse), JT (Joint Transmissions), etc. have been proposed (see Non-Patent Document 2).

[0014] In addition, IEEE802.11 uses Elements as information to be transmitted and received. The format of an Element is shown in Fig. 1, and the table of Element IDs is shown in Fig. 2 (see Non-Patent Document 3).

[0015] First Embodiment In one embodiment of the present invention, APs included in a group (hereinafter referred to as a "Coordination Group") made up of a plurality of APs capable of cooperative communication perform Multi-AP cooperative communication.

[0016] 3 shows an example of the configuration of the STA 300. The STA 300 includes a transmission frame generation unit 301, a control circuit 302, a wireless transmission / reception circuit 303, a frame reception unit 304, and a reception quality measurement unit 305. At least one of the transmission frame generation unit 301, the control circuit 302, the frame reception unit 304, and the reception quality measurement unit 305 may constitute the control unit 306.

[0017] The transmission frame generation unit 301 generates a transmission frame based on input data and control information generated by the control circuit 302 , and outputs the transmission frame to the radio transmission / reception circuit 303 .

[0018] The control circuit 302 generates control information based on input data, control information from the frame receiving section 304 , reception quality from the reception quality measuring section 305 , and internal state, and outputs the control information to the transmission frame generating section 301 .

[0019] The wireless transmission / reception circuit 303 encodes and modulates the transmission frame generated by the transmission frame generation unit 301 to generate a baseband transmission signal (also called a PPDU: Physical layer Protocol Data Unit).The wireless transmission / reception circuit 303 also converts the PPDU into a high frequency signal (also called an RF: Radio Frequency signal) and outputs it to an antenna.

[0020] The radio transmission / reception circuit 303 receives a radio signal using an antenna and outputs it to the frame receiving section 304 and the reception quality measuring section 305 .

[0021] The frame receiving section 304 outputs the output data received in the decoded frame, and also outputs control information to the reception quality measuring section 305 and the control circuit 302 .

[0022] The reception quality measuring unit 305 measures the reception quality based on the signal received by the radio transmission / reception circuit 303, the control information received by the frame receiving unit 304, and the internal state.

[0023] [Configuration of AP] Fig. 4 shows an example configuration of AP 400. AP 400 includes a transmission frame generation unit 401, a control circuit 402, a wireless transmission / reception circuit 403, a reception frame decoding unit 404, a reception quality measurement unit 405, and a cooperative control unit 406. The configuration of AP 400 may be a configuration in which cooperative control unit 406 is added to the configuration of STA 300 shown in Fig. 3. At least one of transmission frame generation unit 401, control circuit 402, reception frame decoding unit 404, reception quality measurement unit 405, and cooperative control unit 406 may form a control unit 407.

[0024] The transmission frame generation unit 401, the control circuit 402, the wireless transmission / reception circuit 403, the reception frame decoding unit 404, and the reception quality measurement unit 405 may have the same functions as the transmission frame generation unit 301, the control circuit 302, the wireless transmission / reception circuit 303, the frame reception unit 304, and the reception quality measurement unit 305. The cooperative control unit 406 generates cooperative control information for controlling cooperative communication based on the input data, the control information from the reception frame decoding unit 404, the reception quality from the reception quality measurement unit 405, and the internal state, and outputs the generated cooperative control information to the control circuit 402.

[0025] <Example 1> As an example, Fig. 5 shows an example of the arrangement of APs and STAs. An example of operation when STA3 stops in a state in which three APs and three STAs shown in Fig. 5 are arranged and performing cooperative communication is shown. In the example of the arrangement of APs and STAs shown in Fig. 5, AP1 is the AP that controls the cooperative communication (also referred to as the coordinator AP, primary AP, controller AP, or master AP; hereinafter referred to as the "coordinator AP"), and AP2 and AP3 are APs whose cooperative communication is controlled (also referred to as coordinated APs, secondary APs, agent APs, or slave APs; hereinafter referred to as the "coordinated APs"). Inter-AP communication between AP1 and AP2 and between AP2 and AP3 is wireless, with STA1 associated with AP1, STA2 associated with AP2, and STA3 associated with AP3.

[0026] The overall steps are shown in Fig. 6. As shown in Fig. 6, after multi-AP setup S601, each AP performs multi-AP measurement S602 and multi-AP transmission S603.

[0027] Fig. 8 shows a Coordination Group list notification format. In Multi-AP setup S601, AP1, which is the coordinator AP, forms a Coordination Group based on information about neighboring APs, such as information contained in a received Beacon. Each AP may create a list of APs included in the Coordination Group (hereinafter referred to as a "Coordination Group list") and notify neighboring APs of the Coordination Group list. The Coordination Group list may be notified using the Coordination Group list notification format shown in Fig. 8.

[0028] In the example arrangement shown in FIG. 5, AP1 cannot receive the Beacon transmitted by AP3, but AP2 may forward the information contained in the Beacon of AP3 to AP1, and the Coordination Group list may be (AP1, AP2, AP3).

[0029] In the multi-AP measurement S602, the AP and / or STA may perform interference measurement by referring to the Coordination Group list. For example, each AP may measure interference with APs included in the Coordination Group list and STAs associated with the APs included in the Coordination Group list.

[0030] Each AP may request APs included in the Coordination Group list and STAs associated with the APs included in the Coordination Group list to measure interference from the APs and STAs to be measured, and have each AP and STA transmit an interference measurement report to the AP that instructed the interference measurement. Each AP may also transmit a Coordination Group list to its associated STAs, have the STAs refer to the list to measure interference, and report the interference measurement results to the AP as an interference measurement report. The interference measurement request format shown in FIG. 13 may be used for the interference measurement request. The interference measurement report format shown in FIG. 14 may be used for the interference measurement report.

[0031] Each AP may send a trigger to associated STAs to instruct them to perform interference measurements.

[0032] In this operation example, STA1 may measure interference from AP2, AP3, STA2 associated with AP2, and STA3 associated with AP3, which are indicated in the Coordination Group list, and transmit an interference measurement report to AP1 with which STA1 is associated. STA1 may perform multi-AP measurement periodically, or may perform it, for example, when the path loss changes. STA1 may not perform multi-AP measurement S602 when operating in a cooperative method that does not require interference measurement, such as C-OFDMA or C-TDMA. AP1 may notify AP2 and AP3, which are indicated in the Coordination Group list, of the interference measurement report via inter-AP communication.

[0033] In Multi-AP Transmission S603, the AP that acquires the TXOP becomes the Sharing AP, and the Sharing AP refers to the interference measurement report from the Multi-AP Measurement S602 and performs cooperative communication with multiple APs included in the Coordination Group as the source or destination.

[0034] An example of the operation in which, while each AP is performing the Multi-AP measurement S602 or the Multi-AP transmission S603 shown in Figure 6, STA3 associated with AP3 has no more data to send or receive, and STA3 stops sending or receiving data will be described.

[0035] 9 shows an update notification format. AP3 may notify AP2 that there is no more data to send or receive with associated STA3, for example, using the update notification format shown in FIG. 9. Upon receiving the update notification format, AP2 may forward the received update notification format to AP1. AP1 may delete AP3 from the Coordination Group list based on the information contained in the update notification format that AP3 has stopped sending or receiving data.

[0036] AP1 may notify AP2 of the deleted list using, for example, the Coordination Group list notification format shown in FIG.

[0037] In this way, by deleting the AP that has stopped transmitting and receiving data from the Coordination Group list and updating the Coordination Group list, it is possible to reduce the number of APs and STAs that are the measurement targets of Multi-AP measurement S602, thereby reducing the amount of information on interference measurement results that STAs notify APs of, and improving throughput. Furthermore, by reducing the number of STAs that are the measurement targets, it is possible to reduce the power consumption of STAs. Furthermore, since inter-AP communication such as coordination control information for APs deleted from the Coordination Group list is no longer necessary, throughput is improved.

[0038] When STA3 resumes operation or a new STA associates with AP3 and AP3 starts transmitting and receiving data, AP3 may notify AP2 that it has started transmitting and receiving data, for example, using the update notification format shown in FIG. 9, and AP2 may transfer the update notification format to AP1. AP1 may add AP3 to the Coordination Group list based on the information in the update notification format that AP3 has started transmitting and receiving data. AP1 may notify AP2 of the Coordination Group list to which AP3 has been added, for example, using the Coordination Group list notification format shown in FIG. 8. AP2 may transfer the received Coordination Group list notification format to AP3.

[0039] When AP3 is stopped, for example, AP3 may transmit a deletion notification during its shutdown process. AP2 may transmit a deletion notification to AP1 when it is unable to receive the beacon from AP3 for a predetermined time. Here, the predetermined time may be the maxlostbeacons shown in Non-Patent Document 3, or a new value may be used to determine whether the AP is stopped.

[0040] A configuration may be adopted in which a Coordinator AP is not determined. Each AP may create a Coordination Group list for each AP based on information about neighboring APs, for example. Information about neighboring APs may be obtained based on received Beacons. An AP that receives an update notification such as addition or deletion using the update notification format shown in FIG. 9 may update its own Coordination Group list.

[0041] Furthermore, each AP may broadcast its own Coordination Group list to neighboring APs. The Coordination Group list may be broadcast, for example, by being included in a Beacon. Since each AP broadcasts its Coordination Group list, when an AP or STA receives an unupdated Coordination Group list, it may determine that the AP that sent the unupdated Coordination Group list failed to receive the update notification, and the AP or STA that receives the updated Coordination Group list may forward the Coordination Group list.

[0042] In addition, although an example of operation using a Coordination Group list has been shown, instead of using a Coordination Group list, the Coordinator AP may have information equivalent to the Coordination Group list and control the Coordinated AP, or each AP may individually have information equivalent to the Coordination Group list.

[0043] An AP may be included in multiple Coordination Groups. For example, in the AP arrangement example shown in Figure 7, which is a different arrangement example from Figure 5, AP2 may generate two Coordination Groups {(AP1,2), (AP2,3)}, one consisting of (AP1,2) and the other consisting of (AP2,3). The Coordination Groups may be distinguished by an identification number such as a Coordination Group ID.

[0044] [Format Example] Control information related to Multi-AP may be notified using the Element format shown in FIG. 1. For example, an Element ID of 255 and an Element ID Extension of 111 in the Element ID table shown in FIG. 2 may be a Multi-AP element. While the Element ID Extension value is 111 as an example, it may be another value that indicates that the element is a Multi-AP element. The Multi-AP element may be included in, for example, information in a Management frame (e.g., a Beacon, Probe Response, Association Request, Re-Association Request, Association Response, or Re-Association Response frame), or in another Action frame newly defined in the 11be standard or a successor standard. Furthermore, control information related to Multi-AP may be notified in a format other than the Element format. The Multi-AP element may be called by another name, for example, a Multi-AP Information element.

[0045] The value of the Type field may indicate the subtype (also called variant) of the Multi-AP element. For example, in the Multi-AP element, Type=0 and Type=1 may be used as formats for Multi-AP setup, Type=2 may be used as a Coordination Group list notification format, Type=3 may be used as an update notification format, Type=4 may also be used as an interference measurement request format, and Type=5 may be used as an interference measurement report format.

[0046] 8 shows an example of a Coordination Group List Notification format. The Coordination Group List Notification format includes identifiers of one or more APs or BSSs included in the Coordination Group (e.g., BSSID, MAC address, BSS color, etc.). The Coordination Group List Notification format may include an identifier indicating the Coordination Group, such as a Coordination Group ID. As an example, the Coordination Group List Notification format may include one or more BSS IDs included in the Coordination Group ID.

[0047] An example of an update notification format is shown in Figure 9. The update notification format includes an update type and a BSS ID. The update type indicates the content to be notified; for example, 0 indicates deletion and 1 indicates addition. It may also be that 1 indicates deletion and 0 indicates addition. The BSS ID indicates the identifier of the AP or BSS to be updated, such as BSSID, MAC address, or color.

[0048] Although the above description is given of the case where the Coordination Group list notification format and the update notification format are defined as subtypes of the Multi-AP element, the information included in the Coordination Group list notification format and the update notification format may also be included in another element (e.g., a Multi-AP Information element) or a format other than the Element format (e.g., a frame, a field, etc.) and notified.

[0049] <Example 2> An example of operation when APs participating in a Coordination Group communicate with each other via a backhaul line will be described. The backhaul line may be wired, wireless, or a combination of wired and wireless. The wired line may be, for example, Ethernet. The wireless line may be, for example, a BSS with an SSID different from that used for AP-STA communication, wireless LAN communication outside the BSS such as pre-association communication or OCB (Outside the context of a BSS), or another wireless communication method.

[0050] For example, the Wi-Fi Easy Mesh procedure may be used to build a multi-AP configuration. A multi-AP controller included in a coordinator AP may control cooperative communication, such as updating the coordination group list. Notifications regarding cooperative communication between APs may be sent between station management entities (SMEs) and MAC sublayer management entities (MLMEs) via the multi-AP controller.

[0051] As an example, the following describes an example of the operation of updating the Coordination Group list when AP1 is the Coordinator AP and STA3 stops while cooperative communication is being performed in the same arrangement example shown in Figure 5 as in Example 1.

[0052] 10 shows an operation sequence in this operation example. In the AP3 shown in FIG. 10, for example, the SME of the AP3 may notify the MLME of the AP3 of the deactivation of STA3 by an MLME-DISASSOCIATE.request (S1001). In the IEEE 802.11 standard, the SME may be referred to as an upper layer.

[0053] The MLME (MAC layer) of AP3, which has received the MLME-DISASSOCIATE.request, notifies the SME of AP3 of an MLME-DISASSOCIATE.response (S1002), and may also determine that cooperative communication targeting AP3 is unnecessary because there are no STAs associated with AP3 due to the shutdown of STA3 and AP3 stops sending and receiving data.

[0054] The MLME of AP 3 may notify the SME of AP 3 of the stop of cooperative communication of AP 3, for example, by using an MLME-MULTIAP-RECONFIGURATION.indication (S1003). Note that the notification of the stop of cooperative communication may have the same data structure as the update notification format shown in FIG.

[0055] The SME of AP3 may notify the Multi-AP Controller of AP1 of the termination of AP3's cooperative communication as an update notification for AP3 via wired inter-AP communication (S1004). The Multi-AP Controller of AP1 may update the Coordination Group list to remove AP3 from it.

[0056] The Multi-AP Controller of AP1 may notify the SMEs of AP1 and AP2 of the updated Coordination Group list (S1005, S1007).

[0057] The SMEs of AP1 and AP2 may notify the MAC layers of AP1 and AP2 by sending an MLME-MULTIAP-RECONFIGURATION.request to the MLMEs of AP1 and AP2 (S1006, S1008). The MLME-MULTIAP-RECONFIGURATION.request may use a data structure similar to the Coordination Group List Notification format shown in FIG. 8. Upon receiving the updated Coordination Group List Notification format, the MLMEs of AP1 and AP2 may transmit measurement requests and / or measurement reports to APs included in a list of APs, such as a list of BSS IDs, included in the updated Coordination Group List Notification format, and / or measure the reception quality of Beacon frames, other frames, and / or NDPs transmitted from the APs included in the list. Furthermore, the MLMEs of AP1 and AP2 may stop transmitting measurement requests and / or measurement reports to APs not included in the updated list, such as AP3, and may stop measuring the reception quality of Beacon frames, other frames, and / or NDPs transmitted from APs included in the list.

[0058] By updating the Coordination Group list in this way, it is possible to reduce the number of measurement targets in the Multi-AP measurement S602, as in the first embodiment, thereby improving throughput and reducing the power consumption of the STA.

[0059] Note that when STA3 resumes operation or a new STA associates with AP3 and AP3 starts transmitting and receiving data, AP3 may notify the Multi-AP Controller via the MLME and SME of AP3 and inter-AP communication between AP3 and AP1. In this case, MLME-MULTIAP-RECONFIGURATION.indication may be used for notification between the MLME and SME of AP3, and may have the same data configuration as the update notification format shown in Fig. 9.

[0060] Furthermore, the Multi-AP controller may perform a similar operation when AP3 is stopped. For example, the Multi-AP controller may check the response of each AP by pinging or the like, remove APs that do not respond from the Coordination Group list, and update and notify the Coordination Group list.

[0061] Alternatively, the Multi-AP Controller may not manage the Coordination Group list; for example, the MAC layer of each AP may manage its own list. In this case, an update notification may be sent in the MLME-MULTIAP-RECONFIGURATION.request and / or the MLME-MULTIAP-RECONFIGURATION.response instead of the Coordination Group list. Alternatively, both the update notification and the Coordination Group list may be sent. Alternatively, the MAC layer of each AP may be specified whether or not to manage its own Coordination Group list in, for example, the MLME-START.request sent from a higher layer at startup or the MLME-START.response sent to the higher layer. The notification content may be switched depending on whether or not the AP manages its own Coordination Group list.

[0062] Also, an example of operation in which the Multi-AP Controller controls cooperative communication has been shown, but in the case of an Extended Service Set (ESS) configuration, a control device that controls the ESS instead of the Multi-AP Controller may control cooperative communication.

[0063] Furthermore, a configuration may be adopted in which both wired and wireless inter-AP communication are used. In this case, the operation of the first embodiment may be performed when the inter-AP communication is wireless, and the operation of the second embodiment may be performed when the inter-AP communication is wired.

[0064] <Example 3> Example 1 and Example 2 have shown operation examples in which a Coordination Group is reconfigured due to the shutdown of an AP or a STA, but Example 3 shows an example in which cooperative communication is controlled in consideration of the influence of interference using a group consisting of multiple APs performing cooperative communication (hereinafter referred to as a "Coordination Set"). A Coordination Group is a group of access points that may perform cooperative communication, and a Coordination Set is a group of access points in a Coordination Group for which cooperative communication is actually valid.

[0065] As an example, FIG. 11 shows an example of an arrangement in which three APs and three STAs are arranged. An example of the operation of STA2 moving in the direction of the arrow while cooperative communication is being performed in the arrangement example of FIG. 11 will be described. In the arrangement example shown in FIG. 11, inter-AP communication between AP1 and AP3 and between AP2 and AP3 is wireless, and STA1 is associated with AP1, STA2 is associated with AP2, and STA3 is associated with AP3. It is also assumed that AP2 and STA2 associated with AP2 are only affected by interference from AP1 and STA1 associated with AP1 before moving. The Coordination Group list in Example 3 is the same as in Example 1, i.e., (AP1, AP2, AP3).

[0066] Each AP may register the identifier of the AP affected by interference in the Coordination Set if the AP and the STA associated with the AP are affected by interference from an AP and / or a STA associated with the AP included in the Coordination Group shown in Example 1 or Example 2.

[0067] Fig. 12 shows an example of an operation sequence in the example arrangement shown in Fig. 11. AP1 receives a frame transmitted by AP3 (S1201) and thereby recognizes that it is affected by interference from AP3.

[0068] When AP1 recognizes that AP3 has transmitted a frame based on the BSS color included in the preambles of the received frame, it may determine that it is affected by interference from AP3 and register AP3 in its Coordination Set (S1202). Similarly, AP2 may register AP3, and AP3 may register AP1 and AP2 in its Coordination Set.

[0069] Next, each AP may update the Coordination Set based on the presence or absence of interference in the associated STAs. For example, AP1 may send an interference measurement request to the associated STA1 (S1203). Figure 13 shows an example of the interference measurement request format. The interference measurement request may specify a reporting action to be taken when an interfering signal is received.

[0070] Upon receiving the interference measurement request, STA1 may transmit an interference measurement report to AP1 if there is an effect of interference (S1204). Fig. 14 shows an example of an interference measurement report format. In the deployment example shown in Fig. 11, STA1 is affected by interference from STA2. Based on the BSS color included in the preambles of the received frame, STA1 transmits an interference measurement report to AP1 indicating that it is affected by interference from STA2 associated with AP2.

[0071] AP1 may add AP2 to the Coordination Set based on the received interference measurement report (S1205).

[0072] AP2 and AP3 perform the same process as AP1. AP2 may transmit an interference measurement request to STA2 with which it is associated (S1206). STA2 may transmit to AP2 that it is affected by interference from STA1 and / or AP1 (S1207). AP2 may add AP1 to its Coordination Set (S1208).

[0073] Each AP may refer to a Coordination Set instead of the Coordination Group shown in the first and second embodiments to perform the Multi-AP measurement S602 and the Multi-AP transmission S603 shown in FIG.

[0074] Each AP may transmit an interference measurement request (shown in Fig. 13) to associated STAs to detect changes in the reception environment. For example, AP2 may transmit an interference measurement request to STA2 (S1206, S1209). The interference measurement request may specify a reporting action to be taken when an interfering signal from STA1 and / or AP1 is no longer received.

[0075] An example of operation will be described below in which, while each AP is performing the multi-AP measurement S602 and multi-AP transmission S603 shown in Figure 6, STA2 moves away from AP1 and is no longer affected by interference from STA1 and AP1.

[0076] Since STA2 is no longer affected by interference from STA1 and AP1 due to its movement, it may transmit an interference measurement report indicating no interference effect to AP2 in response to the received interference measurement request (S1209) (S1210). AP2 may delete AP1 from the Coordination Set based on the received interference measurement report (S1211).

[0077] In this way, even when a Coordination Set is used instead of a Coordination Group, it is possible to reduce the number of APs and STAs to be measured in Multi-AP measurement S602, thereby reducing the amount of information on interference measurement results that STAs notify APs of. As a result, throughput is improved. Reducing the number of STAs to be measured reduces the power consumption of the STAs. Furthermore, by limiting inter-AP communication to APs included in the Coordination Set, unnecessary inter-AP communication can be prevented, thereby improving throughput.

[0078] By using a Coordination Set, which is a group that actually performs cooperative communication from a Coordination Group, it is possible to manage groups that have the potential to perform cooperative communication semi-fixedly in the Coordination Group, while managing groups that are currently performing cooperative communication depending on the interference situation in the Coordination Set.

[0079] AP2 may notify AP1 of whether or not AP1 can be deleted from the Coordination Set (S1212). For example, the confirmation may use the update notification format shown in Fig. 9. Instead of confirming whether or not AP1 can be deleted, AP1 may be notified of the Coordination Set from which AP1 has been deleted.

[0080] Upon receiving confirmation of whether or not AP1 can be removed, AP1 may transmit an interference measurement request for AP2 and STAs associated with AP2 to STA1 (S1213). The interference measurement request may specify an operation to report the presence or absence of an interfering signal.

[0081] Upon receiving the interference measurement request, STA1 may transmit an interference measurement report indicating whether or not there is an interference effect to AP1 (S1214). Since STA2 has already moved, STA1 may transmit an interference measurement report to AP1 indicating that there is no interference effect from STA2.

[0082] AP1 may transmit an update notification response to AP2 based on the interference measurement report of STA1 (S1215). AP2 may perform the process of deleting AP1 from the Coordination Set (S1211) after receiving the update notification response (S1215).

[0083] If AP1 is notified in S1214 by STA1 that there is an interference impact in the interference measurement report, AP1 may transmit to AP2 an update notification response denying the removal of AP1 from AP2's Coordination Set. If AP1 is notified in S1214 by STA1 that there is no interference impact in the interference measurement report, AP1 may transmit to AP2 an update notification response affirming the removal of AP1 from AP2's Coordination Set. The update notification response may use the interference measurement report format shown in FIG. 14.

[0084] AP1 may delete AP2 from its Coordination Set based on the update notification to AP2 or the interference measurement result of STA1 (S1216), thereby updating the Coordination Sets of both AP1 and AP2.

[0085] Although an example of an operation in which AP1 transmits an interference measurement request to STA1 has been shown, it may also be transmitted to all associated STAs via broadcast information. This allows AP1 to check with all STAs associated with AP1 whether or not there is an interference effect from AP2 and STAs associated with AP2. Also, while an example of an operation in which the interference measurement request specifies an operation to report the presence or absence of an interfering signal, it may also be possible to specify an operation to report when an interfering signal is received. This makes it possible to prevent interference measurement reports from being sent from STAs that do not receive interfering signals.

[0086] Although an example of operation using a Coordination Group and a Coordination Set has been shown, a configuration may be adopted in which only a Coordination Group is used and APs with little interference impact are removed from the Coordination Group.

[0087] Although the example of the operation in which the influence of interference is determined based on whether or not an interfering signal is received has been shown, it may also be determined that there is an influence of interference when the received power of the interfering signal is equal to or greater than a threshold. In this case, a threshold for the received power may be added to the format of the interference measurement request shown in FIG. 13 .

[0088] When STA2 returns to a position where it receives interference from AP1, such as its original position, it may notify AP2 that it has received an interference signal, for example, in the format of an interference measurement report shown in FIG. 14 . In this case, AP2 may transmit an interference measurement request to STA2 in advance. The interference measurement request may specify an operation to be reported when an interference signal from STA1 and / or AP1 is received. AP2 may add AP1 to its Coordination Set and notify AP1 of whether or not to add AP1, similar to the operation when STA2 is deleted.

[0089] 11, in the case where direct inter-AP communication is not possible between AP1 and AP2, the notification may be made via AP3, for example, or may be made by a higher layer. The notification by a higher layer may include a wired notification.

[0090] The Coordinator AP may manage the Coordination Set of APs included in the Coordination Group. For example, if AP3 is the Coordinator AP in FIG. 11 , AP2 may transmit an interference measurement report of interference caused by STA2 to AP3. AP3 may transmit an interference measurement request to AP1 based on the interference measurement report received from AP2. AP1 may perform interference measurement based on the interference measurement request received from AP3 and transmit an interference measurement report to AP3. AP3 may update the Coordination Set in accordance with the interference measurement reports received from AP2 and AP1, and transmit a list of APs included in the updated Coordination Set (hereinafter referred to as the "Coordination Set list") to AP1 and AP2.

[0091] The Coordination Set list may be transmitted using the Coordination Group list notification format shown in FIG. 8. To identify whether the notification target is a Coordination Group list or a Coordination Set list, identification information (e.g., a ListType field) may be added to the Coordination Group list notification format, with "ListType=0" indicating that the notification target is a Coordination Group list and "ListType=1" indicating that the notification target is a Coordination Set list. The Coordination Group IDs included in the Coordination Group list notification format may be different numbers for the Coordination Group list and the Coordination Set list. For example, Coordination Group IDs of 128 and above may be notification targets for Coordination Groups, and Coordination Set IDs of 127 and below may be notification targets for Coordination Sets. By using different numbers for the Coordination Group list and the Coordination Set list, identification information (e.g., the ListType field) may be omitted.

[0092] Although an example of an operation in which a Coordination Set is created by referencing a Coordination Group has been shown, a Coordination Set may also be created without referencing a Coordination Group.

[0093] Interference impact information for each AP or BSS may be added to the Coordination Set list and / or Coordination Group list. For example, interference impact information for each BSS may be added to the Coordination Group member list notification format shown in FIG. 8. The interference impact information may be, for example, "0: interference from AP and STA, 1: interference from AP only, 2: interference from STA only, 3: no interference." By requesting interference measurement of STAs by referring to the interference impact information, unnecessary measurement requests can be prevented. For example, in FIG. 11, the Coordination Group member list of AP2 after adding the interference impact information is "AP1(2), AP3(1)" (the values ​​in parentheses indicate the value of the interference impact information) before STA2 moves, and becomes "AP1(3), AP3(1)" after STA2 moves. AP2 may transmit an interference measurement request shown in FIG. 12 to STA2, which is affected by interference from an AP (i.e., AP1) whose interference impact information is 2, i.e., which is only affected by STAs.

[0094] Instead of adding interference impact information to the Coordination Set list and / or the Coordination Group list, for example, a list may be created that compiles APs that are subject to "interference only from STAs."

[0095] [Format Example] The interference measurement request format is shown in Fig. 13. The interference measurement request may be in the interference measurement request format shown in Fig. 13. Fig. 13 shows an example where Type=4 is set in the Multi-AP element.

[0096] The format of the interference measurement request shown in Fig. 13 includes Measurement Type, Duration, BSS ID, and STA ID. Measurement Type indicates the interference measurement method. Duration indicates the measurement time according to the interference measurement method indicated by Measurement Type. BSS ID indicates the BSS ID of the AP and STA that are the object of interference measurement, such as BSS color. STA ID indicates the ID of the STA that performs the measurement, such as AID.

[0097] Measurement Type indicates the type of interference measurement method, for example, 0-3.

[0098] For example, Measurement Type=0 indicates that if the target interfering signal is not received after the time indicated by Duration has elapsed after receiving the interference measurement request format or the interfering signal (hereinafter referred to as the "target interfering signal") from the measurement target specified by the BSS ID, an interference measurement report is transmitted; if the target interfering signal is received before the time indicated by Duration has elapsed, an operation to check for the presence or absence of an interfering signal is repeatedly performed for each time indicated by Duration. The interference measurement report may use the interference measurement report format shown in FIG. 14. The interference measurement request S1206 from AP2 to STA2 before STA2 moves, as shown in FIG. 11, may specify Type=0. If Type=0 is specified for the interference measurement request S1206, STA2 does not transmit the interference measurement report S1207, but monitors until it no longer receives the interfering signal. When STA2 no longer receives the interfering signal, for example, when STA2 moves and no longer receives the interfering signal from STA1 / AP1, STA2 transmits the interference measurement report. A report of the reception of the interfering signal may be transmitted for each period indicated by Duration.

[0099] For example, Measurement Type=1 indicates that the presence or absence of a target interfering signal is transmitted in an interference measurement report after the time indicated by Duration has elapsed since the format of the interference measurement request was received. The interference measurement report may use the interference measurement report format shown in Fig. 14. The interference measurement requests S1203 and S1213 from AP1 to STA1 shown in this embodiment may specify Type=1.

[0100] For example, Measurement Type=2 indicates that an interference measurement report is transmitted when a target interfering signal is received. In this embodiment, the interference measurement request S1209 from AP2 to STA2 after STA2 has moved may specify Type=2. If Type=2 is specified in the interference measurement request S1209, STA2 monitors until it receives an interfering signal without transmitting the interference measurement report of S1210. When STA2 receives an interfering signal, such as when it returns to its original location and receives an interfering signal from STA1 / AP1, STA2 transmits the interference measurement report. A report that an interfering signal is not received may be sent for each period indicated by Duration, or in the case of Measurement Type=2, Duration may be excluded from the format. The interference measurement report format of FIG. 14 may be used for the interference measurement report.

[0101] For example, Measurement Type=3 may instruct the termination of interference measurement requests specified by Measurement Type=0 and 2. The interference measurement request may use the format shown in FIG.

[0102] The AP may control the destination and type of the interference measurement request based on the STA's capability information. For example, the AP may transmit an interference measurement request with Measurement Type=0 or 2 to a STA that does not require power consumption reduction, and upon receiving an interference measurement report from the STA, transmit an interference measurement request with Measurement Type=1 to a STA that requires power consumption reduction. This reduces the interference measurement time and / or the number of interference measurement reports for the STA that requires power consumption reduction, preventing an increase in power consumption. The interference measurement report format shown in FIG. 14 may be used for the interference measurement report.

[0103] By including multiple BSS IDs in the interference measurement request format, an interference signal may be notified to multiple targets using one interference measurement request format.

[0104] In the case of transmission to an individual STA, the STA ID may be omitted from the interference measurement request format.

[0105] The interference measurement report format is shown in Fig. 14. The interference measurement report may be in the interference measurement report format shown in Fig. 14. Note that Fig. 14 shows an example in which Type=5 is set in the Multi-AP element.

[0106] The interference measurement report format shown in Fig. 14 includes Detect. Detect indicates the presence or absence of an interfering signal with respect to the target specified in the interference measurement request shown in Fig. 13. 0 may indicate no interference and 1 may indicate the presence of interference, or alternatively, 1 may indicate no interference and 0 may indicate the presence of interference.

[0107] In the interference measurement request format shown in FIG. 13, in the case of a response to Measurement Type=0 and 2, the Detect field may be omitted, or an Ack may be transmitted instead of the interference measurement report.

[0108] In the interference measurement request format shown in FIG. 13, for example, when a plurality of BSS IDs are specified, the BSS IDs to be reported may be added to the interference measurement report format.

[0109] 13 and 14 show examples of the formats of the interference measurement request and interference measurement report by Multi-AP element, but for example, when the APs are connected via a wired connection, the interference measurement request and interference measurement report may be notified via a higher layer. In this case, the information indicated in the interference measurement request and interference measurement report may be notified by MLME-MULTIAP-RECONFIGURATION.request and / or MLME-MULTIAP-RECONFIGURATION.response.

[0110] (Embodiment 2) In one embodiment of the present disclosure, a list of cooperative communication APs for which cooperative communication is enabled for each cooperative method is notified. In one embodiment of the present disclosure, a group (hereinafter referred to as a "cooperative communication group") consisting of APs for which cooperative communication is enabled is created, and the APs included in the cooperative communication group perform cooperative communication. The configurations of the STAs and APs may be the same as those shown in embodiment 1.

[0111] <Example 4> As an example, an example of a state in which cooperative communication is performed in an arrangement of four APs and four STAs as shown in Fig. 15 will be described below. In the arrangement shown in Fig. 15, STA1 is associated with AP1, STA2 with AP2, STA3 with AP3, and STA4 with AP4. Furthermore, the Coordination Group lists of AP1, AP2, AP3, and AP4 shown in Example 1 are all (AP1, AP2, AP3, AP4).

[0112] Each AP may create a cooperative communication group from the coordination group.

[0113] For example, the cooperative schemes C-OFDMA, C-TDMA, C-CSR, and C-BF are effective when there is interference between an AP and a STA. For each AP, a list of APs that are affected by interference (hereinafter referred to as an "interference impact list") may be created, and the cooperative schemes C-OFDMA, C-TDMA, C-CSR, or C-BF may be executed using the APs included in the interference impact list.

[0114] The cooperative JT method may, for example, be an operation in which data to be transmitted is transferred between multiple APs and the multiple APs transmit simultaneously. In JT, if APs are connected wirelessly and have a low MCS, i.e., if the path loss between APs is large, the transmission bandwidth and / or transmission time required for data transfer between APs increases, resulting in a decrease in throughput. In other words, a group of APs for which JT is effective is a group consisting of wired APs and / or APs with small path loss between APs. A list of APs for which JT is effective is called a JT list. Note that small path loss between APs may be defined as a case in which the path loss, which is the distance between APs, is sufficiently smaller than the radio wave propagation distance of the APs. The cooperative JT method may be executed using APs included in the JT list.

[0115] An example of the operation of AP2 in the arrangement shown in FIG. 15 to create an interference impact list will be described.

[0116] Each AP creates a Coordination Group list using the same operations as in the Multi-AP setup described in the first and second embodiments. When a Beacon is received from an AP included in the Coordination Group list, the AP that transmitted the received Beacon is added to the interference impact list. In the example of deployment shown in FIG. 15, the interference impact list for AP2 is (AP1, AP3). Furthermore, each AP may transmit an interference measurement request for other APs and STAs associated with the other APs to the associated STA. This interference measurement request may be, for example, an interference measurement request format specifying Measurement Type=2. The STA that receives the interference measurement request may transmit an interference measurement report to the AP.

[0117] In the example deployment shown in Fig. 15, STA2 associated with AP2 receives a frame transmitted by STA4. Based on the BSS color included in the preamble of the received frame, STA2 may transmit to AP2 information indicating the presence of interference from AP4 in the interference measurement report format shown in Fig. 14. AP2 may add AP4 to its interference impact list.

[0118] In the arrangement shown in FIG. 15, an example of the operation in which AP2 creates a JT list will be shown.

[0119] Each AP creates a Coordination Group list by performing the same operation as the Multi-AP setup S601 shown in the first and second embodiments, and when it receives a Beacon from an AP included in the Coordination Group list, it adds the AP that transmitted the Beacon with the highest reception power to the JT list. In the example of the arrangement shown in Fig. 15, AP2 may add AP1 to the JT list.

[0120] An example of a cooperative communication group list notification format is shown in FIG. 16. The cooperative communication group created by each AP may be transmitted to the APs and / or coordinator AP included in the cooperative communication group using, for example, the cooperative communication group list notification format shown in FIG. 16. If the cooperative communication group list held by each AP does not match the cooperative communication group list received from another AP, each AP may request a revision of the cooperative communication group list by transmitting, for example, the update notification format shown in FIG. 9 to the AP and / or coordinator AP that transmitted the received cooperative communication group list. In the revision request, for example, the Coordination Type shown in FIG. 16 may be added as the target to be updated to the update notification format shown in FIG. 9.

[0121] In this way, by creating a cooperative communication group, an AP can select an available AP for each cooperative method to be executed. In addition, by each AP transmitting a cooperative communication group list to APs included in the cooperative communication group and / or the coordinator AP, the cooperative communication group lists held by APs executing cooperative communication can be made to be the same list.

[0122] [Format Example] A cooperative communication group list notification format is shown in Fig. 16. The cooperative communication group list notification may be notified using the cooperative communication group list notification format shown in Fig. 16. Fig. 16 shows an example where Type=6 is set in the Multi-AP element.

[0123] The coordinated communication group list notification format includes a Coordination Group ID, a Coordination Type, a num BSS, and a BSS ID.

[0124] Coordination Group ID indicates the same identifier as the Coordination Group ID shown in Fig. 8. Coordination Type indicates the coordination method of the cooperative communication group list, such as an interference impact list or a JT list. num BSS is the number of APs included in the cooperative communication group list of the coordination method indicated by Coordination Type, and indicates the number of BSS IDs following num BSS. BSS ID is the ID of an AP included in the cooperative communication group list of the coordination method indicated by Coordination Type, and indicates the ID of an AP that constitutes the cooperative communication group list.

[0125] If the Coordination Type is JT List, the number of target STAs and the IDs of the STAs may be added to the format.

[0126] Although the embodiments have been described above with reference to the drawings, the present disclosure is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims. It is understood that such modifications or alterations also fall within the technical scope of the present disclosure. Furthermore, the components in the embodiments may be combined in any manner without departing from the spirit of the present disclosure.

[0127] In the above-described embodiments, the notation "... part" used for each component may be replaced with other notations such as "... circuit," "... assembly," "... device," "... unit," or "... module."

[0128] The present disclosure can be realized by software, hardware, or software in conjunction with hardware. Each functional block used in the description of the above embodiments may be partially or entirely realized as an LSI, which is an integrated circuit, and each process described in the above embodiments may be partially or entirely controlled by a single LSI or a combination of LSIs. The LSI may be composed of individual chips, or may be composed of a single chip that includes some or all of the functional blocks. The LSI may have data input and output. Depending on the degree of integration, the LSI may also be called an IC, system LSI, super LSI, or ultra LSI.

[0129] The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit, a general-purpose processor, or a dedicated processor. Also, a field programmable gate array (FPGA) that can be programmed after LSI manufacturing, or a reconfigurable processor that can reconfigure the connections and settings of circuit cells within the LSI, may be used. The present disclosure may be realized as digital processing or analog processing.

[0130] Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology or other derivative technologies, it is natural that such technology may be used to integrate functional blocks. The application of biotechnology, etc. is also a possibility.

[0131] The present disclosure can be implemented in any type of apparatus, device, or system (collectively referred to as a communication apparatus) having a communication function. The communication apparatus may include a radio transceiver and processing / control circuitry. The radio transceiver may include a receiver and a transmitter, or both as functions. The radio transceiver (transmitter and receiver) may include a radio frequency (RF) module and one or more antennas. The RF module may include an amplifier, an RF modulator / demodulator, or the like. Non-limiting examples of communication devices include telephones (e.g., cell phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still / video cameras), digital players (e.g., digital audio / video players), wearable devices (e.g., wearable cameras, smartwatches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles or mobile transportation (e.g., cars, airplanes, ships), and combinations of the above devices.

[0132] The communication devices are not limited to portable or mobile devices, but also include any kind of non-portable or fixed equipment, devices, and systems, such as smart home devices (such as home appliances, lighting equipment, smart meters or measuring devices, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0133] Communications include data communications via cellular systems, wireless LAN systems, communication satellite systems, and the like, as well as data communications via combinations of these.

[0134] A communications apparatus also includes devices such as controllers and sensors connected or coupled to a communications device that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications device to perform the communications functions of the communications apparatus.

[0135] The communication apparatus also includes infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicates with or controls the various apparatuses listed above, but are not limited to these.

[0136] In recent years, in the field of IoT (Internet of Things) technology, CPS (Cyber ​​Physical Systems) has been attracting attention as a new concept that creates new added value by linking information between physical space and cyberspace. This CPS concept can also be adopted in the above-mentioned embodiment.

[0137] That is, as a basic configuration of a CPS, for example, an edge server located in physical space and a cloud server located in cyberspace can be connected via a network, and processing can be distributed and performed by processors installed on both servers. Here, it is preferable that each piece of processing data generated in the edge server or cloud server is generated on a standardized platform, and the use of such a standardized platform can improve the efficiency of building a system that includes a variety of sensor groups and IoT application software.

[0138] (1) An access point according to one embodiment of the present disclosure includes a transceiver unit that transmits and receives information regarding the reconfiguration of cooperative communication, and a control unit that performs the reconfiguration of cooperative communication in accordance with the received information regarding the reconfiguration of cooperative communication.

[0139] (2) In an access point according to one embodiment of the present disclosure, the transceiver unit transmits information relating to changes in the operation of the access point to nearby access points.

[0140] (3) In an access point according to an embodiment of the present disclosure, in the access point of (1), the control unit adds or removes the access point for which addition or removal has been notified from the access points performing cooperative communication.

[0141] (4) In an access point according to one embodiment of the present disclosure, in the access point of (1), the reconfiguration of the cooperative communication is performed in response to the influence of interference.

[0142] (5) In an access point according to one embodiment of the present disclosure, in the access point of (4), the influence of the interference is based on the results of measuring the influence of interference from the cooperative communication access point and a terminal associated with the cooperative communication access point.

[0143] (6) In an access point according to an embodiment of the present disclosure, in the access point of (4), the information regarding the reconfiguration of the cooperative communication is information regarding an access point for which cooperative communication taking into account the influence of the interference is effective.

[0144] (7) In an access point according to an embodiment of the present disclosure, in the access point of (1), the information regarding the reconfiguration of cooperative communication is information regarding access points for which cooperative communication is valid for each cooperative method.

[0145] (8) In a method for controlling cooperative communication according to an embodiment of the present disclosure, an access point receives information related to reconfiguration of cooperative communication and performs reconfiguration of cooperative communication in accordance with the received information.

[0146] The disclosures of the specification, drawings and abstract contained in Japanese Patent Application No. 2022-201270, filed on December 16, 2022, are incorporated herein by reference in their entirety.

[0147] The present disclosure is useful for cooperative communications.

[0148] 300: STA 301, 401: Transmission frame generation unit 302: Control circuit 303: Wireless transmission / reception circuit 304: Frame reception unit 305, 405: Reception quality measurement unit 306, 407: Control unit 400: AP 402: Control circuit 403: Wireless transmission / reception circuit 404: Received frame decoding unit 406: Cooperative control unit

Claims

1. A receiving unit that receives control information for controlling cooperative communication, If the received control information includes information regarding reconstruction, a control unit performs the reconstruction of the cooperative communication according to the control information, An access point having

2. The control unit, when the received control information includes information regarding the setup of the cooperative communication, performs the setup of the cooperative communication according to the control information. The access point according to claim 1.

3. The information relating to the setup includes an identifier of the access point performing the cooperative communication, The access point according to claim 2.

4. The control information is notified using an action frame, The information regarding the setup and reconfiguration of the aforementioned cooperative communication is communicated in the action frame using different values ​​from each other. The access point according to claim 2.

5. The receiving unit receives the control information from another access point via a backhaul line. The access point according to claim 2.

6. The control information is received as a notification between SMEs via the backhaul line and is notified from the SME of the access point to the MLME. The access point according to claim 5.

7. The access point further comprises a transmitting unit that transmits information regarding changes in the operation of the access point to surrounding access points. The access point according to claim 1.

8. The control unit adds or removes the access point that has been notified of being added or removed from the access points that perform cooperative communication. The access point according to claim 1.

9. The access point transmits an interference measurement request to a terminal associated with the access point. The access point according to claim 1.

10. The aforementioned coordinated communication is reconfigured according to the effects of interference. The access point according to claim 9.

11. The aforementioned interference effects are based on the results of measuring the interference effects from the access point of the cooperative communication and the terminals associated with the access point of the cooperative communication. The access point according to claim 10.

12. The information relating to the reconfiguration of the cooperative communication is information relating to access points where the cooperative communication is effective, taking into account the effects of interference. The access point according to claim 10.

13. The information regarding the reconfiguration of the aforementioned cooperative communication is information regarding access points where cooperative communication is effective for each cooperative method. The access point according to claim 1.

14. The access point receives control information for controlling cooperative communication. If the received control information includes information regarding reconstruction, the cooperative communication is reconfigured according to the control information. A method for controlling cooperative communication.