Station device, access point device, and communication method

Abstract

In the present invention, if a wireless LAN station device moves after a measurement is performed, there is a problem that Multi-AP coordination operation is performed on the basis of incorrect information. A wireless LAN station device reports, to a wireless LAN access point device, information required for an inter-access point device coordination operation in a Multi-AP wireless communication system without requesting from the wireless LAN access point device.

Description

Technical Field

[0001] The present invention relates to a station device, an access point device and a communication method. Background Art

[0002] IEEE802.11be, which is a further acceleration of IEEE802.11 as a wireless LAN (Local Area Network) standard, has been standardized by IEEE (The Institute of Electrical and Electronics Engineers Inc.), and wireless LAN devices based on the draft specification have appeared in the market. Currently, as a successor standard to IEEE802.11be, it is expected that the standardization activities of IEEE802.11bn will begin. The main issue of IEEE802.11bn standardization is to achieve ultra high reliability (Ultra High Reliability: UHR).

[0003] In wireless LAN, frames can be transmitted using unlicensed frequency bands for wireless communication that can be implemented without a license (authorization) from a country or region. In personal applications such as home use, a wireless LAN access point function is included in a line terminal device for connecting to a WAN (Wide Area Network) line such as the Internet, or a wireless LAN access point device (also called an access point device) is connected to a line terminal device, etc., to make Internet access from within the home wireless. That is, wireless LAN station devices (also called station devices) such as smartphones and personal computers can connect to the wireless LAN access point device to access the Internet. In the early days of introducing wireless LAN to homes, the number of wireless LAN access point devices in a home was mostly only one, but recently, multiple wireless LAN access point devices have been introduced to expand the coverage of the wireless LAN usage area within the home. In particular, in order to simplify network construction, a wireless LAN mesh network that makes the communication between wireless LAN access point devices (backhaul) wireless is preferred. On the other hand, in the case of enterprises, in order to improve the reliability of frame transmission, it is preferred that the wireless LAN access point devices are connected by wires such as Ethernet (registered trademark). However, since there is a trade-off between the quality of communication performance and the complexity of device settings, sometimes the connection method between wireless LAN access point devices is determined to be wireless or wired in consideration of this balance and according to the usage situation.

[0004] On the other hand, the 6GHz band (5.925-7.125GHz) can be used as an unlicensed band in the United States, and the use of the lower frequencies (5.925-6.425GHz) of the 6GHz band is allowed in Europe and Japan, and research is also being conducted on the upper frequencies (6.0425-7.125GHz). Similar research is also being conducted in other countries around the world. As a result, wireless LAN will be added to the 2.4GHz band and the 5GHz band, and the 6GHz band is also expected to be used. In order to cope with the expansion of target frequencies, the Wi-Fi Alliance has developed Wi-Fi 6E (registered trademark), an extended version of Wi-Fi 6, which is set to use the 6GHz band.

[0005] The 6GHz band is more precisely the frequency band of 5.925 to 7.125GHz, and as bandwidth, a total of about 1.2GHz can be newly used, that is, 14 channels are added when converted to 80MHz bandwidth channels, and 7 channels are added when converted to 160MHz bandwidth channels. Since sufficient frequency resources can be used, the maximum channel bandwidth that can be used for a wireless LAN communication system (the same as the BSS described later) is expanded from 160MHz in IEEE802.11ax to 320MHz in IEEE802.11be, which is twice as much.

[0006] In the 2.4GHz band, the coverage (communication range) is wider, but the available bandwidth is narrow, and the interference between communication devices is also greatly affected. In the 5GHz band and the 6GHz band, the communication bandwidth is expanded, but the coverage is not expanded. Therefore, in order to implement various services / applications through wireless LAN, it is ideal to bind or switch the frequency bands to be used (2.4GHz band, 5GHz band, 6GHz band, etc. or the channels included in each band, or the sub-channels included in the channel) according to the use case. However, in previous wireless LAN communication devices, it is not possible to bind and use different frequency bands used in communication (2.4GHz band, 5GHz band, 6GHz band, etc.). In addition, in order to switch frequency bands (2.4GHz band, 5GHz band, 6GHz band, etc.), it is necessary to temporarily disconnect the current frequency band and reconnect with other frequency bands.

[0007] Therefore, in IEEE802.11be, MLO (Multi-Link Operation) is regulated, in which a communication device can use multiple frequency bands to perform multiple link connections. As an example, the simultaneous use of three link connections, namely, connection in the 2.4GHz frequency band, connection in the 5GHz frequency band, and connection in the 6GHz frequency band, can be listed. Of course, the combination of frequency bands, channels, and sub-channels, and the number of simultaneous connections are not limited to these combinations, but are various. From the perspective of frequency bands, in the future, millimeter waves (45GHz frequency band, 60GHz frequency band, etc.) can also be used as a link to constitute a multi-link (Multi-Link). According to MLO, a communication device can maintain multiple link connections with different wireless resources and communication settings. That is, by using MLO, a communication device can simultaneously maintain link connections in different frequency bands. Not only can frame transmission and reception using multiple links be performed simultaneously, but also the link connection for frame transmission and reception can be switched (frequency band changed) without reconnection. It should be noted that the links constituting multiple links (Multi-Link) here are also called physical layer links.

[0008] In addition, with respect to IEEE802.11bn standardization, discussions are being conducted on Multi-AP (Multi Access Point) in which multiple wireless LAN access point devices coordinate with each other to send and receive frames to a wireless LAN station device (refer to non-patent document 1). In the prior art, basically, a wireless LAN access point device only considers wireless LAN station devices connected to the device to send frames. However, in a Multi-AP wireless communication system, a wireless LAN access point device performs coordination actions with other wireless LAN access point devices ("coordination actions" may also be referred to as "cooperation"), and can also consider wireless LAN station devices connected to other wireless LAN access point devices to send frames. For example, a wireless LAN access point device (hereinafter referred to as BSS-AP) in the prior art estimates the transmission path characteristics based on channel sounding only for a wireless LAN station device (hereinafter referred to as BSS-STA) connected to the device for beam forming, etc. However, a wireless LAN access point device in a Multi-AP wireless communication system requires other wireless LAN access point devices (hereinafter referred to as OBSS-AP) to also estimate the transmission path characteristics based on channel sounding for the wireless LAN station device (hereinafter referred to as BSS-STA). In order to make the Multi-AP coordination action (also referred to as Multi-AP cooperation, cooperation between access point devices, and coordination action between access point devices) operate efficiently, in addition to the wireless LAN access point device of the connection destination, the wireless LAN station device (BSS-STA) also estimates the transmission path characteristics through channel sounding with a wireless LAN access point device (OBSS-AP) other than the connection destination. In addition to channel detection, it is also useful for the wireless LAN station device (BSS-STA) to obtain other received signal qualities (RSSI, SNR, SINR, CQI, etc.) of wireless LAN access point devices (OBSS-AP) other than the connection destination in addition to the wireless LAN access point device of the connection destination. Prior art literature Non-patent literature

[0009] Non-patent document 1: IEEE 802.11-23 / 0854-00-0, May.2023 Summary of the invention Problem that the invention aims to solve

[0010] The transmission path characteristics or received signal quality between a wireless LAN access point device and a wireless LAN station device change as the wireless LAN station device moves or as people or objects in its environment move. When such changes occur, it is desired that the method of coordinated action between the wireless LAN access point device at the connection destination of the wireless LAN station device and other wireless LAN access point devices also change. In the proposed technology (non-patent document 1), a trigger is applied starting from the wireless LAN access point device side to implement measurement of the transmission path characteristics or received signal quality. However, since it is difficult to sense the movement of the wireless LAN station device from the wireless LAN access point device side, if the wireless LAN station device moves after the measurement is implemented, there is a problem that the Multi-AP coordination action is performed based on incorrect information. Technical Solution

[0011] The communication device and communication method of the present invention for solving the above-mentioned problems are as follows.

[0012] (1) That is, a station device according to an aspect of the present invention is connected to a first access point device, and includes: a receiving unit that receives frames transmitted by a plurality of access point devices including the first access point device; and a transmitting unit that transmits a wireless management frame, the wireless management frame including received signal quality information generated by using each frame transmitted by the plurality of access point devices as a measurement target, wherein when the received signal quality information is requested from the first access point device, the wireless management frame is transmitted using a request frame, and when the received signal quality information is not requested from the first access point device, at least one of a first method and a second method is performed, wherein the first method notifies the received signal quality information from the MLME to the SME using a primitive, and the second method transmits the wireless management frame using an unrequested frame.

[0013] (2) In addition, the station device according to one aspect of the present invention is described in the above (1), wherein execution of the first method and the second method is instructed by a primitive from the SME to the MLME.

[0014] (3) In addition, the station device according to one aspect of the present invention is described in the above (1), wherein the received signal quality information includes at least one of RSSI, SNR, SINR, and CQI of the plurality of access point devices.

[0015] (4) In addition, the station device according to one aspect of the present invention is as described in the above (1), wherein the received signal quality information includes capability information of the plurality of access point devices.

[0016] (5) In addition, the station device according to one aspect of the present invention is described in the above (1), wherein the content of the received signal quality information included in the request frame is different from the content of the received signal quality information included in the non-request frame.

[0017] (6) In addition, the station device according to one aspect of the present invention is as described in the above (1), wherein the received signal quality information includes upper layer traffic requirement information.

[0018] (7) An access point device according to one embodiment of the present invention is an access point device that communicates with a station device, and is connected to a first station device, and includes: a transmitting unit that transmits a frame; and a receiving unit that receives a frame, and receives an unsolicited frame including reception signal quality information transmitted by the first station device, wherein the reception signal quality information is generated by the first station device using each frame transmitted by a plurality of access point devices including the connected access point device as a measurement object.

[0019] (8) A communication method according to an aspect of the present invention is a communication method used in a communication system including a station device, a first access point device communicating with the station device, and one or more access point devices other than the first access point device, wherein the station device is connected to the first access point device, the station device receives frames transmitted by a plurality of access point devices including the first access point device, the station device transmits a wireless management frame, the wireless management frame including received signal quality information generated using each frame transmitted by the plurality of access point devices as a measurement target, the station device transmits the wireless management frame using a request frame when requesting the received signal quality information from the first access point device, and the station device performs at least one of a first method and a second method when not requesting the received signal quality information from the first access point device, the first method notifying the received signal quality information from the MLME to the SME using a primitive, and the second method transmitting the wireless management frame using an unrequested frame. Beneficial Effects

[0020] According to the present invention, in a Multi-AP wireless communication system, it is possible to report the transmission path characteristics and received signal quality between the wireless LAN station device and the surrounding wireless LAN access point devices to the wireless LAN access point device side without instructions from the wireless LAN access point device side, and the method of implementing the Multi-AP coordination action on the wireless LAN access point device side can be changed with low delay according to the report. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a diagram showing an example of a frame structure according to one embodiment of the present invention. Figure 2This is a diagram showing an example of a frame structure according to one embodiment of the present invention. Figure 3 It is a diagram showing an example of communication according to one aspect of the present invention. Figure 4 This is a schematic diagram showing an example of dividing a wireless medium according to one aspect of the present invention. Figure 5 It is a diagram showing a configuration example of a communication system according to one aspect of the present invention. Figure 6 This is a block diagram showing a configuration example of a wireless communication device according to one embodiment of the present invention. Figure 7 This is a block diagram showing a configuration example of a wireless communication device according to one embodiment of the present invention. Figure 8 This is an architectural diagram of a wireless communication device according to one embodiment of the present invention. Fig. 9 This is a diagram showing an example of a primitive sequence according to one embodiment of the present invention. Fig.10 This is a diagram showing an example of a frame structure according to one embodiment of the present invention. Fig.11 It is a diagram showing a configuration example of a communication system according to one aspect of the present invention. Fig.12 This is a schematic diagram of communication according to one embodiment of the present invention. Fig.13 This is a diagram showing an example of a primitive sequence according to one embodiment of the present invention. Fig.14 This is a diagram showing an example of a primitive sequence according to one embodiment of the present invention. Fig.15 This is a diagram showing an example of a frame format according to one embodiment of the present invention. Fig.16 This is a block diagram showing a configuration example of a wireless communication device according to one embodiment of the present invention. Fig.17 This is a diagram showing an example of a frame format according to one embodiment of the present invention. DETAILED DESCRIPTION

[0022] The communication system in this embodiment has a wireless base station device (access point device: Accesspoint, base station device) as a wireless transmission device and a plurality of wireless terminal devices (station device: Station, terminal device). In addition, the network composed of the base station device and the terminal device is called a basic service set (BSS: Basic service set, management range). In addition, the station device in this embodiment can have the function of an access point device. Similarly, the access point device in this embodiment can have the function of a station device. Therefore, in the following, when only a communication device is described, the communication device can represent both a station device and an access point device.

[0023] The base station device and the terminal device within the BSS are set to communicate based on CSMA / CA (Carrier sense multiple access with collision avoidance). In the present embodiment, the infrastructure mode (infrastructure mode) in which the base station device communicates with multiple terminal devices is taken as the object, but the method of the present embodiment can also be implemented in an ad hoc mode (adhoc mode) in which the terminal devices communicate directly with each other. In the ad hoc mode, the terminal device replaces the base station device to form the BSS. The BSS in the ad hoc mode is also referred to as an IBSS (Independent Basic Service Set). In the following, the terminal device that forms the IBSS in the ad hoc mode may also be regarded as a base station device. The method of the present embodiment can also be implemented by Wifi Direct (WiFi Direct (registered trademark)) for direct communication between terminal devices. In WiFi Direct, the terminal device forms a group (Group) instead of the base station device. In the following, in WiFi Direct, the terminal device that is the group owner (Group owner) of the group forming the group may also be regarded as a base station device.

[0024] In the IEEE802.11 system, each device can send frames of multiple frame types with a common frame format. Frames are defined by the physical (Physical: PHY) layer, the medium access control (MAC) layer, and the logical link control (LLC: Logical Link Control) layer.

[0025] Figure 8The diagram shows the architecture of a wireless communication device. The MAC layer is equivalent to the upper layer of the PHY layer. The PHY layer includes a management entity called PLME (Physical Layer Management Entity), and the management function of the PHY layer is activated via the PLME. Similarly, the MAC layer includes a management entity called MLME (Medium Access Control Management Entity), and the management function of the MAC layer is activated via the MLME.

[0026] SME (Station Management Entity) is an entity independent of the layer, which has the function of collecting the status specific to the PHY, MAC and other layers or setting the parameter values ​​specific to the PHY, MAC and other layers. There is an interface called MLME SAP (Service Access Point) between SME and MLME, and the MAC layer and SME interact by exchanging primitives via MLMESAP. Similarly, there is an interface called PLME SAP between SME and PLME, and the PHY layer and SME interact by exchanging primitives via PLME SAP. The primitives have SET and GET actions.

[0027] use Fig. 9As a specific example of the MLME SAP primitive, the MLME-Associate primitive is described. This primitive is used when the station device is connected to the access point device (Association). The SME of the station device issues an MLME association request (MLME-Associate.request) 9-1 to the MLME, and the station device sends an association request frame (AssociateRequest frame) from the PHY layer to the wireless medium through the MLME association request 9-1. When the access point device receives the association request frame 9-2, the MLME of the access point device issues an MLME association indication (MLME-Associate.indication) 9-3 to the SME, and the SME issues an MLME association response (MLME-Associate.response) 9-4 to the MLME. The access point device sends an association response frame (Associate Response frame) 9-5 to the wireless medium from the PHY layer through the MLME association response 9-4. When the station device receives the association response frame 9-5, the MLME of the station device issues an MLME-Associate.confirm 9-6 to the SME, and a series of processes related to the association are completed. If the association is successful, a state in which communication is possible is established between the station device and the access point device.

[0028] In the MLME SAP primitives, in addition to the MLME association primitives, various primitives are prepared according to the purpose for the interaction between the SME and the MAC layer. Similarly, in the PLME SAP primitives, various primitives are prepared according to the purpose for the interaction between the SME and the PHY layer. The SME not only exchanges between the PHY layer and the MAC layer, but also has an interface with the upper layer higher than the MAC layer. Examples of the upper layer include the network layer, the transport layer, the session layer, the presentation layer, the application layer, etc., but are not limited to these, as long as it is a layer higher than the MAC layer.

[0029] The frame of the PHY layer is called a physical protocol data unit (PPDU: PHY protocol data unit, physical layer frame, wireless frame, frame). The PPDU is composed of a physical layer header (PHY header) including header information for signal processing at the physical layer and a physical service data unit (PSDU: PHY service data unit, MAC layer frame) as a data unit processed at the physical layer. The PSDU can be composed of an aggregated MPDU (A-MPDU: Aggregated MPDU) that aggregates multiple MAC protocol data units (MPDU: MAC protocol data unit) as a retransmission unit in a wireless interval.

[0030] The PHY header includes reference signals such as a short training field (STF) for signal detection / synchronization, a long training field (LTF) for obtaining channel information for data demodulation, and control signals such as a signal (SIG) including control information for data demodulation. In addition, according to the corresponding standards, STF is classified into legacy STF (L-STF: Legacy-STF), high throughput STF (HT-STF: Highthroughput-STF), very high throughput STF (VHT-STF: Very high throughput-STF), high efficiency STF (HE-STF: High efficiency-STF) and extremely high throughput STF (EHT-STF: Extremely High Throughput-STF), etc., and LTF and SIG are also classified into L-LTF, HT-LTF, VHT-LTF, HE-LTF, L-SIG, HT-SIG, VHT-SIG, HE-SIG, and EHT-SIG. VHT-SIG is further classified into VHT-SIG-A1, VHT-SIG-A2, and VHT-SIG-B. Similarly, HE-SIG is classified into HE-SIG-A1 to 4 and HE-SIG-B. In addition, a Universal SIGNAL (U-SIG) field assuming a technical update under the same standard and including additional control information may be included.

[0031] Furthermore, the PHY header may include information identifying the BSS of the transmission source of the frame (hereinafter referred to as BSS identification information). The information identifying the BSS may be, for example, the SSID (Service Set Identifier) ​​of the BSS or the MAC address of the base station device of the BSS. In addition, the information identifying the BSS may be a value specific to the BSS other than the SSID and the MAC address (for example, the BSS Color, etc.).

[0032] The PPDU is modulated according to the corresponding standard. For example, if it is the IEEE802.11n standard, it is modulated into an orthogonal frequency division multiplexing (OFDM) signal.

[0033] The MPDU is composed of a MAC header including header information for signal processing at the MAC layer, a MAC service data unit (MSDU) or a frame body as a data unit processed at the MAC layer, and a frame check sequence (FCS) for checking whether there is an error in the frame. In addition, multiple MSDUs can also be aggregated into an aggregated MSDU (A-MSDU: Aggregated MSDU).

[0034] The frame types of the transmission frames of the MAC layer are divided into three categories: management frames (also called Management frames, Management frames, and Wireless Management frames), which manage the connection status between devices, etc.; control frames (also called Control frames, Control frames, and Wireless Control frames), which manage the communication status between devices; and data frames, which include actual transmission data, which are further classified into multiple subframe types. Control frames include Acknowledge (Ack) frames, Request to send (RTS) frames, Clear to send (CTS) frames, etc. Management frames include Beacon (Beacon) frames, Probe request (Probe request) frames, Probe response (Probe response) frames, Authentication (Authentication) frames, Association request (Association request) frames, and Association response (Association response) frames. Data frames include Data (Data) frames and CF-poll (CF-poll: non-contention polling) frames, etc. Each device can grasp the frame type and subframe type of the received frame by reading the content of the frame control field included in the MAC header.

[0035] It should be noted that Ack may also include Block Ack. Block Ack can implement reception completion notification for multiple MPDUs.

[0036] The beacon frame includes a field (Field) that records the period (Beacon interval) for sending beacons and the SSID. The base station device can periodically broadcast beacon frames into the BSS, and the terminal device can grasp the base station devices around the terminal device by receiving the beacon frames. The situation in which the terminal device grasps the base station device based on the beacon frame broadcast by the base station device is called passive scanning. On the other hand, the situation in which the terminal device detects the base station device by broadcasting a probe request frame into the BSS is called active scanning. The base station device can send a probe response frame as a response to the probe request frame, and the content recorded in the probe response frame is the same as that of the beacon frame.

[0037] After the terminal device identifies the base station device, it performs connection processing on the base station device. The connection processing is classified into an authentication process and an association process. The terminal device sends an authentication frame (authentication request) to the base station device to which it wishes to connect. When the base station device receives the authentication frame, it sends an authentication frame (authentication response) to the terminal device including a status code (status code) indicating whether the terminal device can be authenticated. The terminal device can determine whether the device itself is allowed to be authenticated by the base station device by reading the status code recorded in the authentication frame. It should be noted that the base station device and the terminal device can exchange authentication frames multiple times.

[0038] After the authentication process, the terminal device sends a connection request frame to connect to the base station device. When the base station device receives the connection request frame, it determines whether to allow the connection of the terminal device, and sends a connection response frame to notify this message. In addition to the status code indicating whether the connection process can be performed, the connection response frame also records an association identifier (AID: Association identifier) ​​for identifying the terminal device. The base station device can manage multiple terminal devices by setting different AIDs for each terminal device that issues permission to connect.

[0039] After the base station device and the terminal device have completed the connection process, they actually transmit data. In the IEEE802.11 system, a distributed control mechanism (DCF: Distributed Coordination Function), a centralized control mechanism (PCF: Point Coordination Function) and these extended mechanisms (Enhanced distributed channel access (EDCA: Enhanced distributed channel access), hybrid control mechanism (HCF: Hybrid coordination function) etc.) are defined. The following is an example of a base station device sending a signal to a terminal device via DCF.

[0040] In DCF, the base station device and the terminal device perform carrier sense (CS: Carrier sense) to confirm the usage status of the wireless channel around the device itself before communicating. For example, when the base station device as a transmitting station receives a signal higher than the predetermined clear channel assessment level (CCA level: Clear channel assessment level) through the wireless channel, it postpones the transmission of the frame on the wireless channel. Hereinafter, in the wireless channel, the state of detecting a signal above the CCA level is referred to as a busy state, and the state of not detecting a signal above the CCA level is referred to as an idle state. In this way, the CS performed by each device based on the power (received power level) of the actual received signal is called physical carrier sense (physical CS). It should be noted that the CCA level is also referred to as a carrier sense level (CS level) or a CCA threshold (CCA threshold: CCAT). It should be noted that when the base station device and the terminal device detect a signal above the CCA level, they at least enter the action of demodulating the signal of the PHY layer.

[0041] The base station device performs carrier sensing at an inter-frame space (IFS) corresponding to the type of frame to be transmitted, and determines whether the wireless channel is busy or idle. The period of time during which the base station device performs carrier sensing varies depending on the frame type and subframe type of the frame to be transmitted by the base station device. In the IEEE802.11 system, multiple IFSs with different periods are defined, including a short inter-frame space (SIFS) for transmission frames with the highest priority, a polling inter-frame space (PCF IFS) for transmission frames with higher priority, and a distributed control inter-frame space (DCF IFS) for transmission frames with the lowest priority. When the base station device transmits a data frame via DCF, the base station device uses DIFS.

[0042] After the base station device waits for DIFS, it further waits for a random backoff time to prevent frame collisions. In the IEEE802.11 system, the random backoff time is set within the contention window (CW: Contention window). In CSMA / CA, it is premised that the transmission frame sent by a certain transmitting station is received by the receiving station without interference from other transmitting stations. Therefore, when the transmitting stations send frames at the same timing, a conflict occurs between the frames, and the receiving station cannot receive them accurately. Therefore, each transmitting station avoids frame collisions by waiting for a randomly set time before starting to send. When the wireless channel is judged to be idle through carrier sensing, the base station device can start the countdown of the backoff counter, the backoff counter becomes 0 and the transmission right is obtained for the first time, and the frame is sent to the terminal device. It should be noted that during the countdown of the backoff counter, if the base station device judges that the wireless channel is busy through carrier sensing, the countdown of the backoff counter is stopped. Then, when the wireless channel becomes idle, the base station apparatus restarts the countdown of the remaining backoff counter after waiting for the same period (DIFS) as the previous IFS.

[0043] The terminal device as a receiving station receives the frame, reads the PHY header of the frame, and demodulates the received frame. The terminal device can then identify whether the frame is destined for the device itself by reading the MAC header of the demodulated signal. It should be noted that the terminal device can also determine the destination of the frame based on the information recorded in the PHY header (for example, the group identifier (GID: Group identifier, Group ID) recorded in the VHT-SIG-A).

[0044] When the terminal device determines that the received frame is destined for the device itself and can demodulate the frame without error, it must send an Ack frame indicating that the frame can be accurately received to the base station device as the transmitting station. The Ack frame is one of the highest priority frames sent in the standby period of the SIFS period (without occupying the random backoff time). The base station device ends a series of communications by receiving the Ack frame sent by the terminal device. It should be noted that when the terminal device cannot accurately receive the frame, the terminal device does not send Ack. Therefore, when the base station device does not receive the Ack frame from the receiving station within a certain period of time (SIFS + Ack frame length) after the frame is sent, it is considered that the communication has failed and the communication is ended. In this way, the end of a communication (also called a burst) of the IEEE802.11 system must be judged by whether or not an Ack frame is received, except for special cases such as sending broadcast signals such as beacon frames and using fragmentation to divide the transmitted data.

[0045] When the terminal device determines that the received frame is not destined for the device itself, it sets the network allocation vector (NAV) based on the length (Length) of the frame recorded in the PHY header, etc. The terminal device does not attempt to communicate during the time period set to NAV. That is, the terminal device performs the same actions as when the wireless channel is determined to be busy through the physical CS during the time period set to NAV, so the communication control based on NAV is also called virtual carrier sensing (virtual CS). In addition to the case where NAV is set based on the information recorded in the PHY header, NAV is also set through the send request (RTS: Request to send) frame and the receive preparation completion (CTS: Clear to send) frame introduced to eliminate the hidden terminal problem.

[0046] Each device performs carrier sense and autonomously obtains the transmission right for the DCF, and a control station called a point coordinator (PC) of the PCF controls the transmission right of each device in the BSS. Usually, the base station device is a PC and obtains the transmission right of a terminal device in the BSS.

[0047] The communication period based on PCF includes a non-contention period (CFP: Contention free period) and a contention period (CP: Contention period). During the CP period, communication is performed based on the above-mentioned DCF, and during the CFP period, the PC controls the transmission right. The base station device as the PC broadcasts a beacon frame that records the CFP period (CFP Max duration: CFP maximum duration) and the like to the BSS before the communication of the PCF. It should be noted that PIFS is used in the transmission of the beacon frame broadcast at the start of the transmission of the PCF, and it is transmitted without waiting for the CW. The terminal device that receives the beacon frame sets the CFP period recorded in the beacon frame to NAV. Afterwards, until the signal (for example, a data frame including CF-end) that the NAV passes through or the end of the CFP broadcast to the BSS is received, the terminal device can obtain the transmission right only when it receives a signal (for example, a data frame including CF-poll) sent by the PC to obtain the transmission right through signaling notification. It should be noted that, in the CFP period, data packets in the same BSS do not collide, so each terminal device does not use the random backoff time used in DCF.

[0048] The wireless medium can be divided into a plurality of resource units (RUs). Figure 4This is a schematic diagram showing an example of the division state of the wireless medium. For example, in resource division example 1, the wireless communication device can divide the frequency resources (subcarriers) as the wireless medium into nine RUs. Similarly, in resource division example 2, the wireless communication device can divide the subcarriers as the wireless medium into five RUs. Of course, Figure 4 The resource partitioning example shown is only an example. For example, multiple RUs may also be composed of different numbers of subcarriers. In addition, the wireless medium divided into RUs can include not only frequency resources but also space resources. A wireless communication device (such as an AP) can send frames to multiple terminal devices (such as multiple STAs) simultaneously by configuring frames with different terminal devices as destinations in each RU. The AP can include information indicating the partitioning state of the wireless medium (Resource allocation information) as common control information in the PHY header of the frame sent by the device itself. Moreover, the AP can include information indicating the RU configured with frames with each STA as destinations (resource unit assignment information) as inherent control information in the PHY header of the frame sent by the device itself.

[0049] In addition, multiple terminal devices (for example, multiple STAs) can send frames simultaneously by configuring the frames to the allocated RUs and sending them. After receiving a frame (Trigger frame: TF) including trigger information sent from the AP, multiple STAs can send frames after waiting for a specified period of time. Each STA can grasp the RU allocated to the device itself based on the information included in the TF. In addition, each STA can obtain the RU through random access based on the TF.

[0050] The AP can allocate multiple RUs to one STA at the same time. The multiple RUs can be composed of either continuous or discontinuous subcarriers. The AP can use multiple RUs allocated to one STA to send one frame or allocate multiple frames to different RUs and send them. At least one of the multiple frames can be a frame that includes common control information for multiple terminal devices that send resource allocation information.

[0051] An STA can be allocated multiple RUs by an AP. The STA can use the allocated multiple RUs to send a frame. In addition, the STA can use the allocated multiple RUs to allocate multiple frames to different RUs and send them. The multiple frames can be frames of different frame types.

[0052] The AP can assign multiple AIDs to one STA. The AP can assign RUs to the multiple AIDs assigned to one STA. The AP can use the assigned RUs to send different frames to the multiple AIDs assigned to one STA. The different frames can be frames of different frame types.

[0053] An STA can allocate multiple AIDs through an AP. An STA can allocate RUs to the allocated multiple AIDs respectively. An STA can identify the RUs allocated to the multiple AIDs allocated to the device itself as RUs allocated to all devices itself, and send a frame using the allocated multiple RUs. In addition, an STA can use the allocated multiple RUs to send multiple frames. At this time, the multiple frames include information indicating the AIDs associated with the respectively allocated RUs and send them.

[0054] Hereinafter, base station devices and terminal devices are collectively referred to as wireless communication devices or communication devices. In addition, information exchanged between a wireless communication device and other wireless communication devices when communicating is also referred to as data. That is, wireless communication devices include base station devices and terminal devices.

[0055] The wireless communication device has either or both of a function of transmitting PPDU and a function of receiving PPDU. Figure 1 This is a diagram showing an example of the PPDU structure sent by a wireless communication device. The PPDU corresponding to the IEEE802.11a / b / g standard is composed of L-STF, L-LTF, L-SIG and data frame (MAC Frame, MAC frame, payload, data part, data, information bit, etc.). The PPDU corresponding to the IEEE802.11n standard is composed of L-STF, L-LTF, L-SIG, HT-SIG, HT-STF, HT-LTF and data frame. The PPDU corresponding to the IEEE802.11ac standard is composed of L-STF, L-LTF, L-SIG, VHT-SIG-A, VHT-STF, VHT-LTF, VHT-SIG-B and part or all of the MAC frame. The PPDU corresponding to the IEEE802.11ax standard includes L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, HE-STF, HE-LTF, HE-SIG-B and part or all of the data frame in which L-SIG is repeated in time. The PPDU studied in IEEE802.11be includes L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, EHT-SIG, EHT-STF, HET-LTF and part or all of the data frame.

[0056] Depend on Figure 1 The L-STF, L-LTF, and L-SIG surrounded by the dotted line in the figure are common structures under the IEEE802.11 standard (hereinafter, L-STF, L-LTF, and L-SIG are also collectively referred to as L-headers). For example, a wireless communication device corresponding to the IEEE 802.11a / b / g standard can treat the L-header in the PPDU corresponding to the IEEE802.11n / ac standard. As a wireless communication device corresponding to the IEEE802.11a / b / g standard, a PPDU corresponding to the IEEE802.11n / ac standard can be received as a PPDU corresponding to the IEEE802.11a / b / g standard.

[0057] However, wireless communication devices that comply with the IEEE 802.11a / b / g standards cannot demodulate the PPDU that complies with the IEEE 802.11n / ac standards after the L-header, and therefore cannot demodulate information related to the Duration / ID field used to set the sending address (TA: Transmitter Address), receiving address (RA: Receiver Address), and NAV.

[0058] IEEE802.11 specifies a method of inserting duration information into L-SIG as a method for wireless communication devices that conform to the IEEE 802.11a / b / g standards to appropriately set NAV (or perform a reception operation for a specified period of time). Information related to the transmission rate (RATE field, L-RATE field, L-RATE, L_DATARATE, L_DATARATE field) and information related to the transmission period (LENGTH field, L-LENGTH field, L-LENGTH) in L-SIG are used to appropriately set NAV for wireless communication devices that conform to the IEEE 802.11a / b / g standards.

[0059] Figure 2 FIG. 4 is a diagram showing an example of a method of inserting duration information of L-SIG. Figure 2As an example, the PPDU structure corresponding to the IEEE802.11ac standard is shown, but the PPDU structure is not limited to this. It can also be a PPDU structure corresponding to the IEEE802.11n standard, a PPDU structure corresponding to the IEEE802.11ax standard, or a PPDU structure studied in IEEE802.11be. TXTIME has information about the length of the PPDU, aPreambleLength has information about the length of the preamble (L-STF+L-LTF), and aPHYHeaderLength has information about the length of the PHY header (L-SIG). L_LENGTH is based on the signal extension (Signal Extension), which is a virtual time period set to obtain compatibility with the IEEE802.11 standard, and N associated with L_RATE. ops , aSymbolLength which is information about the time period of one symbol (symbol, OFDM symbol, etc.), aPHYServiceLength indicating the number of bits included in the service field, and aPHYConvolutionalTailLength indicating the number of tail bits of the convolution symbol. The wireless communication device can calculate L_LENGTH and include it in the L-SIG. In addition, the wireless communication device can calculate the L-SIG duration. The L-SIG duration represents information about the time period, which totals the PPDU including the L_LENGTH, the Ack expected to be sent by the wireless communication device at the destination as a response thereto, and the SIFS time period.

[0060] Figure 3 This is a diagram showing an example of L-SIG duration in L-SIG TXOP protection. DATA (frame, payload, data, etc.) is composed of a part or both of the MAC frame and the PHY header. In addition, BA is a block Ack or Ack. PPDU can include L-STF, L-LTF, L-SIG, and can be composed to include any one or any multiple of DATA, BA, RTS or CTS. Figure 3 In one example shown, L-SIGTXOP Protection using RTS / CTS is indicated, but CTS-to-Self can also be used. Here, the MAC duration is the period indicated by the value of the Duration / ID field. In addition, the initiator can send a CF_End frame to notify the end of the L-SIGTXOP protection period.

[0061] Next, a method for identifying a BSS based on a frame received by a wireless communication device is described. In order for a wireless communication device to identify a BSS based on a received frame, it is preferred that the wireless communication device that sends the PPDU inserts information for identifying the BSS (BSS Color, BSS identification information, BSS-specific value) into the PPDU. Information indicating the BSS color (BSS Color) can be included in the HE-SIG-A.

[0062] The wireless communication device can send L-SIG multiple times (L-SIG repetition). For example, the wireless communication device on the receiving side improves the demodulation accuracy of L-SIG by receiving the L-SIG sent multiple times using MRC (Maximum Ratio Combining). Moreover, when the wireless communication device accurately completes the reception of L-SIG through MRC, the PPDU including the L-SIG can be interpreted as a PPDU corresponding to the IEEE802.11ax standard.

[0063] The wireless communication device can also perform a reception operation (also referred to as a dual reception operation) of a portion of a PPDU other than the PPDU (for example, a preamble, L-STF, L-LTF, PHYP header, etc. specified by IEEE802.11) during the reception operation of the PPDU. When a portion of a PPDU other than the PPDU is detected during the reception operation of the PPDU, the wireless communication device can update part or all of the information related to the destination address, the transmission source address, the PPDU, or the DATA period.

[0064] Ack and BA may also be referred to as responses (response frames). In addition, probe responses, authentication responses, and connection responses may also be referred to as responses. [1. First embodiment]

[0065] The Multi-AP wireless communication system is composed of a wireless communication system provided by multiple access point devices. Figure 5This is a diagram showing an example of a Multi-AP wireless communication system of the present embodiment, which is an example composed of four wireless communication systems: wireless communication system 3-1, wireless communication system 3-2, wireless communication system 3-3, and wireless communication system 3-4. In a Multi-AP wireless communication system, in addition to the conventional transmission and reception of frames between an access point device and one or more station devices, multiple access point devices can also coordinate actions to transmit and receive frames with station devices. Basically, it is configured so that the communication areas (also called coverage areas. In this example, it is assumed to refer to 3-1, 3-2, 3-3, and 3-4) provided by each wireless communication system overlap (overlap). This example is an example of a Multi-AP wireless communication system composed of four wireless communication systems, but it is only an example, and it can also be composed of multiple wireless communication systems other than four.

[0066] The wireless communication system 3-1 includes an access point device 1-1 and station devices 2-1, 2-12, 2-13, and 2-123. In addition, the station devices 2-1, 2-12, 2-13, and 2-123 are also collectively referred to as station devices 2A (terminal devices 2A) as devices connected (association) to the access point device 1-1. The access point device 1-1 and the station device 2A are wirelessly connected and are in a state where frames can be transmitted and received to each other. Furthermore, the station device 2-12 is connected to the access point device 1-1, but it is also possible to make the access point device 1-1 and the access point device 1-2 coordinate operations and transmit and receive frames between the station device 2-12. The station device 2-13 is connected to the access point device 1-1, but it is also possible to make the access point device 1-1 and the access point device 1-3 coordinate operations and transmit and receive frames between the station device 2-13. The station device 2-123 is connected to the access point device 1-1, but the access point devices 1-1, 1-2, and 1-3 can cooperate to send and receive frames with the station device 2-123. The station device 2-1 sends and receives frames only with the access point device 1-1 as the connection destination.

[0067] The wireless communication system 3-2 includes an access point device 1-2 and base station devices 2-2, 2-21, 2-23, and 2-213. In addition, the station devices 2-2, 2-21, 2-23, and 2-213 are also collectively referred to as station devices 2B (terminal devices 2B) as devices connected (association) to the access point device 1-2. The access point device 1-2 and the station device 2B are wirelessly connected and are in a state where frames can be transmitted and received to each other. Furthermore, the station device 2-21 is connected to the access point device 1-2, but the access point device 1-2 and the access point device 1-1 can also coordinate operations to transmit and receive frames between the station device 2-21. The station device 2-23 is connected to the access point device 1-2, but the access point device 1-2 and the access point device 1-3 can also coordinate operations to transmit and receive frames between the station device 2-23. The station device 2-213 is connected to the access point device 1-2, but the access point device 1-2, the access point device 1-1, and the access point device 1-3 can cooperate to send and receive frames with the station device 2-213. The station device 2-2 sends and receives frames only with the access point device 1-2 as the connection destination.

[0068] The wireless communication system 3-3 includes an access point device 1-3 and station devices 2-3, 2-31, 2-32, 2-34, and 2-312. In addition, the station devices 2-3, 2-31, 2-32, 2-34, and 2-312 are also collectively referred to as station devices 2C (terminal devices 2C) as devices that are connected (association) to the access point device 1-3. The access point device 1-3 and the station device 2C are wirelessly connected and are in a state where frames can be transmitted and received to each other. Furthermore, the station device 2-31 is connected to the access point device 1-3, but the access point device 1-3 and the access point device 1-1 can also coordinate operations to transmit and receive frames to and from the station device 2-31. The station device 2-32 is connected to the access point device 1-3, but the access point device 1-3 and the access point device 1-2 can also coordinate operations to transmit and receive frames to and from the station device 2-32. The station device 2-34 is connected to the access point device 1-3, but the access point device 1-3 and the access point device 1-4 can coordinate operations and transmit and receive frames with the station device 2-34. The station device 2-312 is connected to the access point device 1-3, but the access point device 1-3, the access point device 1-1, and the access point device 1-2 can coordinate operations and transmit and receive frames with the station device 2-312. The station device 2-3 transmits and receives frames only with the access point device 1-3 as the connection destination.

[0069] The wireless communication system 3-4 includes an access point device 1-4 and a base station device 2-4. In addition, the station device 2-4 is also referred to as a station device 2D (terminal device 2D) as a device connected to the access point device 1-4. The access point device 1-4 and the station device 2D are wirelessly connected and are in a state where frames can be transmitted and received mutually. The station device 2-4 transmits and receives frames only to the access point device 1-4 as the connection destination.

[0070] The access point devices 1-1, 1-2, 1-3, and 1-4 constituting the Multi-AP wireless communication system respectively constitute the wireless communication system, but at least one access point device acts as a mother access point device (mother AP) (also called a coordinator access point device (Coordinator AP), a shared access point device (Sharing AP), etc.), and plays a role of issuing instructions to control the child access point devices (child APs) (coordinated access point devices (Coordinated AP), shared access point devices (Shared AP), etc.) as other access point devices. Multiple mother access point devices can also be configured in a Multi-AP wireless communication system to have redundancy or sharing.

[0071] Each access point device constituting the Multi-AP wireless communication system can also relay frames sent to or received from station devices connected to other access point devices. For example, the base station device 2-2 can also receive frames sent by the access point device 1-1 via the access point device 1-2. In addition, the access point device 1-1 can also receive frames sent by the base station device 2-2 via the access point device 1-2.

[0072] Each access point device constituting the Multi-AP wireless communication system can also perform coordination actions between access point devices, and one or more access point devices can send and receive frames with a station device. For example, access point device 1-1 can also participate in the frame transmission and reception with station device 2-21 connected to access point device 1-2.

[0073] There are various methods for the above-mentioned coordination operation between access point devices. As representative methods, there are joint operations (Joint Operation) in which multiple access point devices transmit and receive frames to a station device, joint Tx (Joint Tx: Joint Transmission), joint OFDMA (Joint OFDMA), and joint BF (Joint BF (Beam Forming)) as examples. For example, the data part of the frame destined for the station device 2-21 is shared from the access point device 1-2 to the access point device 1-1, and the access point devices 1-2 and 1-1 are synchronized to send the frame to the station device 2-21, thereby obtaining gain.

[0074] As another representative method, there is a coordinated operation (Coordinated Operation) in which multiple access point devices coordinate to share each other's communication conditions to adjust the use of wireless media, etc., and finally only one access point device performs frame transmission and reception for one station device. Examples include coordinated OFDMA (Coordinated OFDMA), coordinated SR (Coordinated SR (Spatial Reuse)), coordinated BF (Coordinated BF (BeamForming)), coordinated TXOP sharing (Coordinated TXOP Sharing), coordinated TDMA (Coordinated TDMA (Time Division Multiple Access)), etc. For example, in coordinated OFDMA, frequency resources are allocated in a manner that the frequency resources used by access point device 1-1 and access point device 1-2 are not overlapped. Thus, with the station devices 2-12 and 2-21 located in a place where their communication areas (coverage ranges) overlap (overlap), the access point device 1-1 can use frequency resource A for the station device 2-12, and the access point device 1-2 can use frequency resource B that does not overlap with frequency resource A for the station device 2-21, and simultaneously perform frame transmission and reception.

[0075] The method of coordinating operations between access point devices is not limited to the two methods, joint operation, and coordinated operation described here, and there are various other methods.

[0076] Fig.10 An example of the format of a MAC frame is shown in FIG. Figure 1 Data frame in (MAC Frame, MAC frame, payload, data part, data, information bit, etc.), Figure 2 The MAC frame includes: Frame Control, Duration / ID, Address 1, Address 2, Address 3, Sequence Control, Address 4, QoS Control, HT Control, Frame Body, and FCS.

[0077] The wireless communication system 3-1, the wireless communication system 3-2, the wireless communication system 3-3, and the wireless communication system 3-4 form different BSSs, but this does not necessarily mean that the ESSs (Extended Service Sets) are different. ESS represents a service set that forms a LAN (Local Area Network). That is, wireless communication devices belonging to the same ESS can be regarded by the upper layer as belonging to the same network. In addition, the BSSs are combined via the DS (Distribution System) to form an ESS. It should be noted that the wireless communication systems 3-1, 3-2, 3-3, and 3-4 can also each have multiple wireless communication devices.

[0078] Figure 6 The figure shows an example of the device configuration of wireless communication devices 1-1, 1-2, 1-3, 1-4, 2A, 2B, 2C, and 2D (hereinafter, collectively referred to as wireless communication devices 10000-1). The wireless communication device 10000-1 includes an upper layer unit (upper layer processing step) 10001-1, an autonomous distributed control unit (autonomous distributed control step) 10002-1, a transmitting unit (transmitting step) 10003-1, a receiving unit (receiving step) 10004-1, and an antenna unit 10005-1.

[0079] The upper layer unit 10001-1 has the function of a MAC layer, can connect to other networks via a DS (Distribution System), and notify the autonomous distributed control unit 10002-1 of information related to the service. The information related to the service may be information destined for other wireless communication devices, or control information included in management frames and control frames.

[0080] Figure 7 1 is a diagram showing an example of the device configuration of the autonomous distributed control unit 10002-1. The autonomous distributed control unit 10002-1 includes a CCA unit (CCA step) 10002a-1, a backoff unit (backoff step) 10002b-1, and a transmission determination unit (transmission determination step) 10002c-1.

[0081] The CCA unit 10002a-1 can use either or both of the information related to the power of the received signal received via the wireless resource and the information related to the received signal (including decoded information) notified from the receiving unit 10004-1 to perform the state judgment of the wireless resource (including the judgment of being busy or idle). The CCA unit 10002a-1 can notify the back-off unit 10002b-1 and the transmission judgment unit 10002c-1 of the state judgment information of the wireless resource.

[0082] The backoff unit 10002b-1 can use the state judgment information of the wireless resource to perform the backoff process. The backoff unit 10002b-1 has a countdown function for the random backoff time set in the CW. For example, when the state judgment information of the wireless resource shows that it is idle, the countdown of the backoff counter can be performed, and when the state judgment information of the wireless resource shows that it is busy, the countdown of the backoff counter can be stopped. The backoff unit 10002b-1 can notify the value of the backoff counter to the transmission judgment unit 10002c-1.

[0083] The transmission judgment unit 10002c-1 uses either or both of the state judgment information of the wireless resource and the value of the backoff counter to make a transmission judgment. For example, when the state judgment information of the wireless resource indicates that the wireless resource is idle and the value of the backoff counter is 0, the transmission judgment information can be notified to the transmission unit 10003-1. In addition, when the state judgment information of the wireless resource indicates that the wireless resource is idle, the transmission judgment information can be notified to the transmission unit 10003-1.

[0084] The transmission unit 10003-1 is composed of a physical layer frame generation unit (physical layer frame generation step) 10003a-1 and a wireless transmission unit (wireless transmission step) 10003b-1. The physical layer frame generation unit 10003a-1 has a function of generating a physical layer frame (PPDU) based on the transmission judgment information notified from the transmission judgment unit 10002c-1. The physical layer frame generation unit 10003a-1 performs error correction coding, modulation, precoding filter multiplication, etc. on the transmission frame sent from the upper layer. The physical layer frame generation unit 10003a-1 outputs the generated physical layer frame to the wireless transmission unit 10003b-1.

[0085] The physical layer frame generation unit 10003a-1 performs error correction coding on the information bits input from the MAC layer, but the unit for performing error correction coding (coding block length) is not limited to any unit. For example, the physical layer frame generation unit 10003a-1 can divide the information bit sequence input from the MAC layer into information bit sequences of a specified length, perform error correction coding on each of them, and set them as multiple coding blocks. It should be noted that when forming a coding block, virtual bits can also be inserted into the information bit sequence input from the MAC layer.

[0086] The frame generated by the physical layer frame generation unit 10003a-1 includes control information. The control information includes information indicating which RU (here, the RU includes both frequency resources and space resources) the data destined for each wireless communication device is configured in. In addition, the frame generated by the physical layer frame generation unit 10003a-1 includes a trigger frame that instructs the wireless communication device as the destination terminal to send a frame. The trigger frame includes information indicating the RU used when the wireless communication device instructed to send a frame sends a frame.

[0087] The wireless transmission unit 10003b-1 converts the physical layer frame generated by the physical layer frame generation unit 10003a-1 into a signal of a radio frequency band (RF) to generate a radio frequency signal. The processing performed by the wireless transmission unit 10003b-1 includes digital / analog conversion, filtering, and frequency conversion from baseband to RF band.

[0088] The receiving unit 10004-1 is composed of a wireless receiving unit (wireless receiving step) 10004a-1 and a signal demodulation unit (signal demodulation step) 10004b-1. The receiving unit 10004-1 generates information related to the received signal power based on the signal of the RF band received by the antenna unit 10005-1. The receiving unit 10004-1 can notify the CCA unit 10002a-1 of the information related to the received signal power and the information related to the received signal.

[0089] The wireless receiving unit 10004a-1 has the function of converting the RF band signal received by the antenna unit 10005-1 into a baseband signal and generating a physical layer signal (e.g., a physical layer frame). The processing performed by the wireless receiving unit 10004a-1 includes frequency conversion processing from the RF band to the baseband, filtering, and analog / digital conversion.

[0090] The signal demodulation unit 10004b-1 has a function of demodulating the physical layer signal generated by the wireless receiving unit 10004a-1. The processing performed by the signal demodulation unit 10004b-1 includes channel equalization, demapping, error correction decoding, etc. The signal demodulation unit 10004b-1 can extract, for example, information included in the physical layer header, information included in the MAC header, and other information included in the MAC frame based on the physical layer signal. The signal demodulation unit 10004b-1 can output the extracted information to the upper layer unit 10001-1. It should be noted that the signal demodulation unit 10004b-1 can extract any one or all of the information included in the physical layer header, information included in the MAC header, and other information included in the MAC frame.

[0091] The antenna unit 10005-1 has a function of transmitting the radio frequency signal generated by the radio transmission unit 10003b-1 to another radio communication device 10000-1 in a wireless space. In addition, the antenna unit 10005-1 has a function of receiving a radio frequency signal transmitted from another radio communication device 10000-1.

[0092] The wireless communication device 10000-1 can make the PHY header and MAC header of the transmitted frame include information indicating the time period during which the device itself uses the wireless medium, thereby setting NAV for the wireless communication devices around the device itself during the time period. For example, the wireless communication device 10000-1 can make the duration / ID field or length field of the transmitted frame include information indicating the time period. The NAV time period set for the wireless communication devices around the device itself is referred to as the TXOP time period (transmission opportunity time period) (or simply TXOP. Also referred to as a transmission opportunity) obtained by the wireless communication device 10000-1. Moreover, the wireless communication device 10000-1 that obtains the TXOP is referred to as a TXOP holder. The frame type of the frame sent by the wireless communication device 10000-1 to obtain the TXOP is not limited to any frame type, and can be a control frame (such as an RTS frame, a CTS to itself frame) or a data frame.

[0093] The wireless communication device 10000-1 as a TXOP holder can transmit frames to wireless communication devices other than the device itself during the TXOP. In the case where the wireless communication device 1-1 is the TXOP holder, the wireless communication device 1-1 can transmit frames to the wireless communication device 2A during the TXOP period. In addition, the wireless communication device 1-1 can instruct the wireless communication device 2A to transmit frames with the wireless communication device 1-1 as the destination during the TXOP period. The wireless communication device 1-1 can transmit a trigger frame including information indicating the transmission of frames with the wireless communication device 1-1 as the destination to the wireless communication device 2A during the TXOP period.

[0094] The wireless communication device 1 - 1 may secure TXOPs for all communication bands where frames may be transmitted (eg, Operation bandwidth), or may secure a specific communication band such as a communication band where frames are actually transmitted (eg, Transmission bandwidth).

[0095] The wireless communication device that instructs the wireless communication device 1-1 to transmit a frame within the TXOP period obtained is not necessarily limited to the wireless communication device connected to the device itself. For example, the wireless communication device may instruct the transmission of a frame to a wireless communication device that is not connected to the device itself in order to transmit a management frame such as a reassociation frame or a control frame such as an RTS / CTS frame to a wireless communication device located in the vicinity of the device itself.

[0096] Furthermore, the TXOP in EDCA, which is a data transmission method different from DCF, is also described. The IEEE802.11e standard involves EDCA, and therefore defines TXOP from the perspective of QoS (Quality of Service) guarantee for various services such as video transmission and VoIP. Services are roughly classified into four access categories: VO (voice), VI (video), BE (Best Effort), and BK (Background). Generally speaking, the order of priority from high to low is VO, VI, BE, and BK. In each access category, there are parameters such as the minimum value CWmin of CW, the maximum value CWmax, AIFS (Arbitration IFS) as a type of IFS, and the TXOP limit as the upper limit value of TXOP, and the values ​​are set to have a difference in priority. For example, by setting the CWmin, CWmax, and AIFS of VO, which has the highest priority for voice transmission, to relatively smaller values ​​than other access categories, data transmission can be given priority over other access categories. For example, in VI with a large amount of transmission data for video transmission, the TXOP limit can be set larger to achieve a longer TXOP than other access categories. In this way, the values ​​of the four parameters of each access category are adjusted for the purpose of ensuring QoS corresponding to various services.

[0097] In this embodiment, the signal demodulation unit 10004b-1 of the station device can perform decoding processing in the physical layer for the received signal and perform error detection. Here, the decoding processing includes decoding processing for the error correction code applied to the received signal. Here, the error detection includes error detection using an error detection code (such as a cyclic redundancy check (CRC) code) pre-assigned to the received signal, and error detection based on an error correction code (such as a low-density parity check code (LDPC)) that originally has an error detection function. The decoding processing in the physical layer can be applied to each coding block.

[0098] The upper layer unit 10001-1 receives the decoding result of the physical layer in the signal demodulation unit 10004b-1, and restores the MAC layer signal. In addition, the MAC layer performs error detection to determine whether the MAC layer signal sent by the station device that is the source of the received frame can be accurately restored.

[0099] The wireless communication device may be a multi-link device (MLD) capable of multi-link communication. An access point device corresponding to MLD is referred to as an MLD access point device, and a station device corresponding to MLD is referred to as an MLD station device. In addition, an MLD access point device and an MLD station device are also collectively referred to as an MLD wireless communication device.

[0100] use Fig.16 The MLD access point device 20000-1 and the MLD station device 30000-1 are described. The MLD wireless communication device is composed of a plurality of sub-wireless communication devices corresponding to the frequency bands (or channels, or sub-channels) of each link (also called a physical layer link) constituting the multi-link. Fig.16 In FIG. 1 , an example is shown in which the MLD access point device 20000-1 is composed of three sub-wireless communication devices, in this case, three sub-access point devices (20000-2, 20000-3, and 20000-4), but the number of sub-access point devices may be any number greater than one. Fig.16 In the example shown, the MLD station device 30000-1 is composed of three sub-wireless communication devices, in this case, three substation devices (30000-2, 30000-3, 30000-4), but the number of substation devices is any number greater than one. It should be noted that the sub-wireless communication device (sub-access point device, substation device, etc.) can be composed of a part of the circuit in the wireless communication device, and can also be called a sub-wireless communication unit (sub-access point unit, substation unit).

[0101] exist Fig.16 In the figure, for the sake of explanation, a plurality of sub-wireless communication devices are shown logically as independent blocks (rectangles), but they can also be physically configured as one wireless communication device. Alternatively, they can also be physically configured as independent sub-wireless communication devices. In this case, each sub-access point device sends and receives necessary information through the connections 9-1 and 9-2, and each substation device sends and receives necessary information through the connections 9-3 and 9-4. In this embodiment, it is assumed that the MLD wireless communication device is physically configured as one wireless communication device (10000-1). This configuration is similar to the above-mentioned configuration using Figure 6 , Figure 7 The contents described are the same.

[0102] It should be noted that the number of sub-access point devices included in an MLD access point device and the number of sub-station devices included in an MLD station device may vary according to the level, category, and capability of each MLD wireless communication device. For MLD wireless communication devices with higher levels, higher categories, and higher capabilities, the number of sub-wireless communication devices (sub-access point devices, sub-station devices) carried may be greater. That is, for each MLD wireless communication device located in a wireless communication system, the number of sub-wireless communication devices (sub-access point devices, sub-station devices) constituting each MLD wireless communication device may vary according to the level, category, and capability, and their numbers may not be consistent.

[0103] The substation device 30000-2 is connected (Association) with the sub-access point device 20000-2 to establish link 1. The substation device 30000-3 is connected (Association) with the sub-access point device 20000-3 to establish link 2. The substation device 30000-4 is connected (Association) with the sub-access point device 20000-4 to establish link 3. In the description of this embodiment, the number of links constituting the multi-link is three, but it is not limited to this and can be any number. In the description of this embodiment, the carrier frequency of link 1 is set to the 2.4 GHz band, the carrier frequency of link 2 is set to the 5 GHz band, and the carrier frequency of link 3 is set to the 6 GHz band. However, the frequency used by each link can be the 2.4 GHz band, the 5 GHz band, the 6 GHz band, and the 60 GHz band. In addition, it can be arbitrarily set from the frequency bands, channels, and sub-channels supported by the wireless communication system, and it will also change according to the laws and regulations of each country.

[0104] use Fig.11 An example of a wireless communication system including a station device and an access point device according to the present embodiment will be described. Fig.11 Extracted and shown Figure 5The access point device 1-1, the station devices 2-1, 2-12, 2-13, and 2-123 connected to the access point device 1-1, the access point devices 1-2 and 1-3 that coordinate operations with the access point device 1-1, and the access point device 1-4 that does not coordinate operations with the access point device 1-1. In addition, for the purpose of supplementary explanation, the station devices 2-2, 2-3, 2-4, and 2-34 are also added. In addition, it is assumed that the frame 11-11 is transmitted from the access point device 1-1 to the station device 2-123, the frame 11-12 is transmitted from the station device 2-123 to the station device 1-1, the frame 11-21 is transmitted from the access point device 1-2 to the station device 2-123, the frame 11-22 is transmitted from the station device 2-123 to the station device 1-2, the frame 11-31 is transmitted from the access point device 1-3 to the station device 2-123, and the frame 11-32 is transmitted from the station device 2-123 to the station device 1-3. Here, it is assumed that the access point devices 1-1, 1-2, 1-3, and 1-4 are access point devices that support coordination between access point devices. However, for example, when the station device 2A connected to the access point device 1-1 is the target, the communication area (coverage range) of the access point device 1-4 and the access point device 1-1 do not overlap. Therefore, in this embodiment, the case where the access point device 1-4 and the access point device 1-1 cannot coordinate to communicate with the base station device 2A is described.

[0105] In addition, when the access point device 1-4 does not support the coordination operation between the access point devices, the access point device 1-4 cannot coordinate the operation with other access point devices. For example, although the station device 2-34 connected to the access point device 1-3 is located in the communication area (coverage range) of the access point device 1-4, the access point devices 1-3 and 1-4 communicate only with the access point device 1-3.

[0106] The method of the coordinated operation between the access point devices is not limited, and as an example, a joint operation, a coordinated operation, etc. may be used as described above.

[0107] When performing coordinated actions between access point devices such as joint actions and coordinated actions, it is useful to report received signal quality information (also called received signal statistical information) based on measurements of frame reception conditions from surrounding access point devices observed on the station device side to the access point device side. Furthermore, if the received signal quality information also includes contents based on measurements of frame reception conditions from other station devices (Reported STA) observed by the reporting station device (Reporting STA), it will contribute to better joint actions and coordinated actions.

[0108] The received signal quality information, the frame reception statistics information, the frame transmission statistics information, and the communication volume requirement information described later are referred to as access point device coordination information (also referred to as access point device coordination action information, Multi-AP coordination information, Multi-AP coordination action information, inter-layer coordination information, etc.). The access point device coordination information only needs to include any one of the received signal quality information, the frame reception statistics information, the frame transmission statistics information, and the communication volume requirement information.

[0109] As an example, the frame reception statistics information may use part or all of the information such as BER (Bit Error Rate), FER (Frame Error Rate), BLER (BLock Error Rate), number of received data frames, number of received management frames, etc. of the frames received by the station device. In addition, it is not limited to such information, and information representing the reception statistics of the frame may also be used. As an example, the frame transmission statistics information may use part or all of the information such as the frame contention rate, retransmission rate, CW time, medium occupancy rate, wireless medium busy rate, wireless medium idle rate, channel load, etc. when the station device transmits the frame. It is not limited to these examples, as long as it is statistical information related to frame transmission and reception.

[0110] Traffic requirement (Traffic Requirement, also known as Traffic Specification, Traffic Classification, QoS Characteristics, etc.) information is the traffic requirement of applications operating at the application layer. As an example, part or all of the information such as average throughput, maximum throughput, minimum throughput, tolerable frame error rate, tolerable delay, and tolerable jitter value can be used.

[0111] As an example, the received signal quality value included in the collaboration information between access point devices may use part or all of RSSI (Received Signal Strength Indicator), SNR (Signal to Noise Ratio), SINR (Signal to Interference plus Noise Ratio), CQI (Channel Quality Indication), etc., but is not limited to these, as long as it is a value or indicator for evaluating the quality of the received signal.

[0112] In addition to the access point device 1-1, the inter-access point device cooperation information reported by the station device (in this example, the station device 2-123) to the access point device (in this example, the access point device 1-1) can also be shared (sent) to the coordinator access point device. From the perspective of the base station device 2-123, the information included in the received signal quality information can also be used to determine the access point device with great influence among the access point devices other than the access point device 1-1 as the connection destination (Association destination). The access point device 1-1 (or the Coordinator access point device) can determine the inter-access point device cooperation indication information (also called the inter-access point device coordination action indication information) indicating which other access point device the access point device 1-1 performs what coordination action with which other access point device according to the reported content. It is effective for the access point device side to perform frame transmission and reception with the station device 2-123 through the determined coordination action. An example of the above-mentioned "access point device with great influence" can be an access point device with a large RSSI measured by the station device 2-123 as an example of the information included in the received signal quality information. That is, an access point device other than the access point device 1-1 with a large RSSI may become an interference factor for frame transmission and reception between the access point device 1-1 and the station device 2-123, and is effective as a target of the coordination operation. In addition, the judgment index of "access point device with large influence" is of course not limited to RSSI.

[0113] A specific example will be described by taking RSSI included in the information of the received signal quality information as an example. For example, the station device 2-123 is located in a place (overlapping place) where the communication areas (coverages) of the wireless communication systems 3-1, 3-2, and 3-3 overlap, and is located outside the communication area (coverage) of the wireless communication system 3-4. The base station device 2-123 measures the RSSI of the frames transmitted from each access point device, and sets the RSSI value of the access point device 1-1 to RSSI_1, the RSSI value of the access point device 1-2 to RSSI_2, the RSSI value of the access point device 1-3 to RSSI_3, and the RSSI value of the access point device 1-4 to RSSI_4, and reports it to the access point device 1-1 as the communication object. For example, it is assumed that RSSI_1, RSSI_2, and RSSI_3 are the same value, and RSSI_4 is a value that cannot be measured. During communication with the station device 2-123, the access point device 1-1 (or the Coordinator access point device) determines the access point devices 1-2 and 1-3 reporting larger RSSI as candidates for the coordinated action between access point devices, and determines the access point device 1-4 that cannot measure RSSI due to being outside the communication area as not being a candidate for the coordinated action between access point devices, and implements the coordinated action between access point devices based on these determination results.

[0114] As described above, the access point device 1-1 (or the Coordinator access point device) generates the access point device-to-access device cooperation indication information. When wireless communication can be performed between the access point devices, the access point device can directly send and receive frames including the access point device-to-access device cooperation indication information. As an example, when the access point device 1-1 (or the Coordinator access point device) can perform wireless communication with the access point device (in this example, the access point devices 1-2 and 1-3) that is the target of the access point device coordination action, it can directly send and receive wireless frames including the access point device-to-access device cooperation indication information with the target access point device. For example, the access point device 1-1 sends a frame including the access point device-to-access device cooperation indication information to the access point device 1-2 and the access point device 1-3. The access point devices 1-1, 1-2, and 1-3 can perform the access point device-to-access device cooperation action according to the shared access point device-to-access device cooperation indication information.

[0115] However, in Fig.11 In the example of , the access point devices 1-2 and 1-3 are not located within the communication area (coverage) 3-1 of the access point device 1-1. In this case, wired connections may be established between the access point devices in advance through Ethernet (registered trademark) or the like, and access point device 1-1 may send access point device cooperation indication information to access point devices 1-2 and 1-3 through wired communication.

[0116] As another method of transmitting the access point device cooperation indication information, there is a method via a station device. For example, the access point device cooperation indication information is included in the frame 11-11 sent from the access point device 1-1 to the station device 2-123 and sent. The station device 2-123 that receives the frame 11-11 can include the access point device cooperation indication information in the frame 11-21 and send it to the access point device 1-2. That is, the station device 2-123 can relay the access point device cooperation indication information received from the access point device 1-1 to the access point device 1-2. Similarly, the station device 2-123 that receives the frame 11-11 can include the access point device cooperation indication information in the frame 11-31 and send it to the access point device 1-3. That is, the station device 2-123 can relay the access point device cooperation indication information received from the access point device 1-1 to the access point device 1-3. In this way, the station device 2 - 123 can operate as a relay device that relays the inter-access point device cooperation instruction information received from the access point device to a plurality of access point devices other than the access point device.

[0117] The access point device coordination indication information may be sent to the access point devices (in this example, the access point devices 1-2 and 1-3) that are the objects of the access point device coordination action via a unicast frame (Unicast frame, Individually addressed frame), via a multicast frame (Multicast frame, Group addressed frame), or via a broadcast frame. The access point device coordination indication information may also be sent to the access point devices that are the objects of the access point device coordination action.

[0118] The access point devices (in this example, the access point devices 1 - 1 , 1 - 2 , and 1 - 3 ) that share the inter-APD coordination indication information may use the inter-APD coordination indication information to perform inter-APD coordination operations.

[0119] The access point device-to-device coordination indication information includes information related to a method of coordinating actions between access point devices (also referred to as an action mode, specifying action modes such as joint actions and cooperative actions). When specifying a joint action, as an example, information indicating an action mode such as joint Tx (joint transmission), joint OFDMA, and joint BF (Beam Forming) may be included. When specifying a coordinated action (Coordinated Operation), as an example, information indicating an action mode such as coordinated OFDMA, coordinated SR (Spatial Reuse), coordinated BF (Beam Forming), coordinated TXOP sharing, and coordinated TDMA (Time Division Multiple Access) may be included.

[0120] The access point device-to-device coordination indication information may also include a list of access point devices that perform coordination actions. Fig.11 In the example case, for station device 2-123, since access point devices 1-1, 1-2, and 1-3 perform coordination actions, information related to access point devices 1-1, 1-2, and 1-3 (identification information such as BSSID and individual identification information equivalent thereto) can be included in the access point device list of the coordination actions.

[0121] The access point device cooperation indication information may also include information for performing time synchronization of each access point device. For example, the access point device cooperation indication information may also include the TSF (Time Synchronization Function) of the access point device and the offset of the TSF between each access point device (TSF offset). For example, the access point device cooperation indication information may also include the TSF of the access point device 1-1 in the access point device cooperation indication information for the purpose of transmitting frames in time synchronization among the access point devices 1-1, 1-2, and 1-3. The access point devices 1-2 and 1-3 may also calculate the offset of their respective TSFs based on the TSF of the access point device 1-1.

[0122] The frame that the station device that generates the received signal quality information takes as the measurement object is exemplified by a wireless management frame and a wireless control frame transmitted by the access point device. A beacon frame, which is an example of a wireless management frame, is a frame including the capability information of the access point device, etc., and the access point device does not transmit it only to a specific station device, but broadcasts it to surrounding wireless communication devices. Therefore, the beacon frame is suitable for grasping the standard (normal) transmission characteristics and signal quality of the access point device.

[0123] In addition, the station device that generates the received signal quality information may also include frames sent and received between surrounding access point devices and other specific station devices in the measurement objects in order to understand the communication status other than beacon frames. Unicast frames (Unicast frame, Individually addressed frame), multicast frames (Multicast frame, Groupaddressed frame), etc. may also be included in the measurement objects.

[0124] Furthermore, in the station device generating the received signal quality information, when a frame such as a unicast frame or a multicast frame to which beamforming is applied and which is destined for the other specific station device is used as a measurement object, the measured RSSI may be greater than the RSSI of a broadcast frame such as a beacon. In this case, the station device generating the received signal quality information may also report the received signal quality information generated by comprehensively considering the received signal quality of the frame unicast (or multicast) to the other specific station device to the access point device of the connection destination.

[0125] exist Fig.13In the figure, taking the case where a station device measures the received signal quality of a surrounding access point device as an example, an example of primitives exchanged within a wireless communication device and frames exchanged between wireless communication devices is illustrated. Here, as an example, the primitive name is set to MEASURESTA. In order to confirm the status of frames received from surrounding access point devices in the station device, the SME issues and instructs the primitive MLME-MEASURESTA.request 13-1 to the MLME. The MLME that receives the instruction instructs the MAC layer and the PHY layer to receive frames sent by the surrounding access point devices and measure the received signal quality.

[0126] The station device includes the access point device cooperation information including the reception signal quality information of the frames received from the surrounding access point devices in the report frame (Report frame) 13-2 and sends it, which is received by the access point device. The MLME of the access point device reports the access point device cooperation information included in the report frame 13-2 to the SME through the primitive MLME-MEASURESTA indication (Primitive MLME-MEASURESTA.indication) 13-3, and the reported content can also be used by the upper layer. Here, the upper layer refers to a layer higher than the MAC layer, and the upper layer also includes the application layer. This means that the application layer of the access point device can use the access point device cooperation information including the reception signal quality information of the surrounding access point devices obtained by the station device. In addition, the access point device can also share (send) the access point device cooperation information to the coordinator access point device in the Multi-AP wireless communication system.

[0127] The SME of the access point device or the upper layer of the access point device or the coordinator access point device in the Multi-AP wireless communication system can use the received inter-access point device cooperation information to determine which other access point device to perform and what coordination action to perform.

[0128] As an example, the MLME of the station device reports the access point device cooperation information included in the report frame 13-2 to the SME through the primitive MLME-MEASURESTA confirmation (Primitive MLME-MEASURESTA.confirm) 13-4. The reported content can also be used by the upper layer. That is, the station device can also use the received signal quality information of the surrounding access point devices obtained by itself and other information (frame reception statistics, frame transmission statistics, etc.) included in the access point device cooperation information in its own upper layer.

[0129] The SME of the station device or the upper layer of the station device may also change the traffic requirement information according to the received access point device cooperation information. For example, the frame transmission statistical information may be referred to, and when the wireless medium busy rate is large, the average throughput value of the traffic requirement information may be reduced assuming that the wireless communication environment is poor. In addition, the value included in the traffic requirement information may be changed according to the value included in the received signal quality information, the frame reception statistical information, and the frame transmission statistical information included in the access point device cooperation information.

[0130] It should be noted that, so far, the station device has been described as sending the report frame 13-2 to the access point device of the connection destination (Association destination) after the station device and the access point device are connected (Association), but the report frame 13-2 may be sent to access point devices other than the connection destination, or the report frame 13-2 may be broadcasted without limiting the destination. In addition, the report frame 13-2 may be sent before the station device and the access point device are connected (Association).

[0131] The report frame 13-2 is a frame that is spontaneously sent by the station device without being requested (also called solicited, triggered) by the access point device. In this process, the frame sent from the station device is also called an unsolicited frame. In addition, this method (also called method, mode) is called an unsolicited mode.

[0132] exist Fig.13 In the description of the case where the station device sends the access point device cooperation information through the unsolicited frame, Fig.14 , a case where a request frame (solicited frame) for cooperation information between access point devices is sent by a station device after a request (also called solicitation, trigger) from an access point device is described. This method (also called method, mode) is called solicited mode.

[0133] exist Fig.14, as an example of a case where a station device accepts a request from an access point device and measures the received signal quality of surrounding access point devices, an example of primitives exchanged within a wireless communication device and frames exchanged between wireless communication devices is illustrated. Here, as an example, the primitive name is set to MEASUREAP. In the access point device, in order to request the station device for inter-access point device cooperation information (including received signal quality information, etc.), the SME issues and indicates the primitive MLME-MEASUREAP request (Primitive MLME-MEASUREAP.request) 14-1 to the MLME. The MLME receiving the instruction sends a report request frame (Report Request frame) 14-2 to the station device, and the station device receives it. The station device sends an MLME-MEASUREAP indication (MLME-MEASUREAP.indication) 14-3 from the MLME to the SME, and the SME issues an MLME-MEASUREAP response (MLME-MEASUREAP.response) 14-4 to the MLME. This is equivalent to instructing the MAC layer and the PHY layer to receive frames transmitted by the surrounding access point devices and measure the quality of received signals.

[0134] The station device includes the access point device cooperation information including the received signal quality information in the report response frame (Report Response frame) 14-5 and sends it, and it is received by the access point device. The MLME of the access point device reports the access point device cooperation information (including the received signal quality information) included in the report response frame 14-5 to the SME through the primitive MLME-MEASUREAP confirmation (Primitive MLME-MEASUREAP.confirm) 14-6, and the reported content can also be used by the upper layer. Here, the upper layer refers to a layer higher than the MAC layer, and the upper layer also includes the application layer. This means that the application layer of the access point device can use the access point device cooperation information including the received signal quality information of the surrounding access point devices obtained by the station device. In addition, the access point device cooperation information can also be shared (sent) from the access point device to the coordinator access point device in the Multi-AP wireless communication system.

[0135] The station device can extract the access point device cooperation information reported to the access point device through the report response frame 14-5 to the SME of the station device or the upper layer of the station device. Here, as an example, the primitive name is set to MEASURESELF. The SME sends an MLME-MEASURESELF request (MLME-MEASURESELF.request) 14-7 to the MLME. The MLME reports the content or a part of the access point device cooperation information included in the report response frame 14-5 to the SME through the primitive MLME-MEASURESELF confirmation (Primitive MLME-MEASURESELF.confirm) 14-8, and the reported information can also be used by the upper layer.

[0136] It should be noted that, so far, the station device has been described as sending the report response frame 14-5 to the access point device of the connection destination (Association destination), but it can also be sent to access point devices other than the connection destination, and can also be broadcasted without limiting the destination. In addition, the access point device can also send the report request frame 14-2 to the station device (Unassociated STA) that is not connected (Association), and in response, the station device sends the report response frame 14-5 to the access point device. In the case of the unassociated STA (Unassociated STA), the report response frame 14-5 can also be broadcasted without limiting the destination.

[0137] The SME of the access point device or the upper layer of the access point device or the coordinator access point device in the Multi-AP wireless communication system can use the inter-access point device coordination information to determine which other access point devices the access point device performs and what coordination action it performs.

[0138] Information other than the received signal quality may also be included in the access point device cooperation information generated by the station device. For example, part or all of the frame reception statistical information and frame transmission statistical information as statistical information related to the frame transmission and reception of the station device may also be included. Examples of frame reception statistical information include BER (BitError Rate), FER (Frame Error Rate), BLER (BLock Error Rate), number of received data frames, number of received management frames, and other information of the frames received by the station device. Examples of frame transmission statistical information include frame contention rate, retransmission rate, CW time, medium occupancy rate, medium busy rate, medium idle rate, channel load, and the like when the station device transmits frames. It is not limited to these examples, as long as it is statistical information related to frame transmission and reception.

[0139] Can be issued from SME to MLME by the on-site device Fig.13 The primitive MLME-MEASURESTA request 13-1, Fig.14 The primitive MLME-MEASUREAP response (primitive MLME-MEASUREAP.response) 14-4 in the protocol includes information from the upper layer. The traffic requirement values ​​of the application operating at the application layer may also be included in these primitives. For example, when the application is a motion picture reproduction application, information indicating the traffic requirement information desired by the application, such as the average throughput, maximum throughput, minimum throughput, tolerable frame error rate, tolerable delay, and tolerable jitter value required for motion picture reproduction, may be included. It should be noted that the traffic requirement information may also be included in the access point device collaboration information.

[0140] As an example of the primitive sequence in the unsolicited frame mode, Fig.13 However, it is not necessary to execute all primitives, and other primitives can be appended. As an example of the primitive sequence in the request frame mode, Fig.14 , but not all primitives are necessarily executed, and other primitives can be added and executed. The verbs "request", "confirm", "indication", and "response" attached to the end of the primitive name can also be used with Fig.13 , Fig.14 The contents of the illustrations are different.

[0141] use Fig.12 The frame transmission and reception diagram is described by taking the case where a station device measures the received signal quality from the RSSI of the beacon frame of the surrounding access point device as an example.

[0142] Here, the measurement object time is set to t1. The measurement object time can be a fixed value, a variable value, or determined by negotiation during association. The measurement object time t1 can also be set to MIB. The measurement object time t1 can also be set by primitive. In the case of unsolicited frame mode, Fig.13 In the station device in the SME, the primitive MLME-MEASURESTA request 13-1 is issued to the MLME to indicate the measurement target time t1. In the case of the request mode, Fig.14In the access point device shown, the primitive MLME-MEASUREAP request 14-1 is issued from the SME to the MLME, and the measurement target time t1 is indicated to the MLME of the station device using the report request frame 14-2 and the like sent in response thereto. Parameters related to the received signal quality measurement, such as the frame type (beacon frame, unicast frame, multicast frame, management frame, data frame, control frame, etc.) and the number of frames to be measured, can be determined in the same manner as the method for determining the measurement target time t1 described above.

[0143] exist Fig.12 In the example, only the minimum necessary frames are described for the purpose of explanation, but other frames may actually be transmitted and received. The description assumes that the measurement target time t1 is specified, but the frame type and the number of frames may be used as other parameters. It is assumed that the wireless LAN access point device 1-1 transmits beacon frames 12-11, 12-12, 12-13, and 12-14, the wireless LAN access point device 1-2 transmits beacon frames 12-21, 12-22, 12-23, and 12-24, the wireless LAN access point device 1-3 transmits beacon frames 12-31, 12-32, 12-33, and 12-34, and the wireless LAN access point device 1-4 transmits beacon frames 12-41, 12-42, 12-43, and 12-44. The wireless LAN station device 2-123 calculates RSSI as the received signal quality information of the wireless LAN access point device 1-1 from the beacon frames 12-11, 12-12, 12-13, and 12-14, calculates RSSI as the received signal quality information of the wireless LAN access point device 1-2 from the beacon frames 12-21, 12-22, 12-23, and 12-24, calculates RSSI as the received signal quality information of the wireless LAN access point device 1-3 from the beacon frames 12-31, 12-32, 12-33, and 12-34, and calculates RSSI as the received signal quality information of the wireless LAN access point device 1-4 from the beacon frames 12-41, 12-42, 12-43, and 12-44. The calculation of RSSI as the received signal quality information uses the average value, maximum value, minimum value, and the like in the measurement target time t1.

[0144] The received signal quality information of the frames to be measured may be generated based on all frames received in the time period t1, or based on a portion of the frames. For example, when generating the received signal quality information of the access point device 1-3, all of the frames 12-31, 12-32, 12-33, and 12-34 may be used, or only the frames 12-31 and 12-32 may be used as a portion of the frames. Fig.12Only the beacon frames broadcast as the objects for generating the received signal quality information are recorded, but unicast frames (Unicast frame, Individually addressed frame), broadcast frames (Broadcast frame), and multicast frames (Multicast frame, Group addressed frame) which are other frame categories can also be used as measurement objects based on the negotiation, MIB, and primitives during the above-mentioned association.

[0145] The base station device 2-123 reports the measurement result of the received signal quality of the surrounding wireless LAN access point devices at the measurement object time t1 to the access point device through a report frame 12-51 (also called a report response frame 12-51). The frame 12-51 can also be unicast (Unicast, Individually addressed) only to the access point device 1-1 of the connection destination (Association destination). The access point device cooperation information included in the report frame 12-51 can also be shared from the access point device 1-1 of the connection destination (Association destination) to the coordinator access point device. The report frame 12-51 can also be broadcast (Broadcast) or multicast (Multicast, Group addressed) so that other access point devices also receive the report frame 12-51. The wireless LAN access point device 1-1 (or Coordinator access point device) can grasp the status of the access point devices around the station device 2-123 based on the access point cooperation information shown in the report frame 12-51, and determine how to coordinate actions with other access point devices for communication with the station device 2-123.

[0146] exist Fig.15 An example of the structure of the report frame 12-51 (also referred to as the report response frame 12-51) sent by the station device 2-123 is shown in FIG. It should be noted that the PHY header, MAC header, etc. are omitted. The report frame 12-51 includes access point cooperation information. The access point cooperation information only needs to include at least one of the received signal quality information, received frame statistical information, sent frame statistical information, and communication volume requirement information.

[0147] exist Fig.11In the case of the wireless communication system shown, the station device 2-123 can receive frames from the access point devices 1-1, 1-2, and 1-3, and includes the measurement results of the access point devices 1-1, 1-2, and 1-3 in the report frame 12-51. On the other hand, since the station device 2-123 cannot receive frames from the access point device 1-4, the measurement result of the access point device 1-4 may not be included in the report frame 12-51. The received signal quality information is information related to the signal quality of the frames transmitted from the access point devices around the station device 2-123, including information such as RSSI, SNR, SNIR, and CQI, and part or all of the information such as the corresponding BSSID and SSID can be used in the identification information as information for identifying the access point device. For example, the received signal quality information 1 corresponds to the access point device 1-1, the received signal quality information 2 corresponds to the access point device 1-2, and the received signal quality information 3x corresponds to the received signal quality information corresponding to the access point device 1-3. The information of the access point device 1 - 1 to which the station device 2 - 123 is connected (Association) may be included in the inter-access point cooperation information or may not be included therein.

[0148] As an example, in the access point coordination information, the received signal quality information of each access point device may be arranged in the order of the signal quality determined by the station device from high to low, and in the order recommended as the coordination destination. Fig.15 In the case of the example of , the order of the received signal quality values ​​of the station devices from high to low or the order preferred as the coordination destination may be set to the order of received signal quality information 1, received signal quality information 2, and received signal quality information 3, or the reverse order. However, the received signal quality information does not necessarily need to be arranged based on the reference of the station device, and the access point device side that receives the report frame 12-51 may also determine the signal quality of each access point device based on the reference of the access point device side.

[0149] In the case of the request mode and the case of the unrequest frame mode, a difference may be set in the content of the access point device cooperation information included in the report frame 12-51 (also referred to as the report response frame 12-51). For example, it may be set to include the communication volume requirement information in the case of the unrequest frame mode but not include the communication volume requirement information in the case of the request mode. For example, it may be set to include the communication volume requirement information in the case of the unrequest frame mode but include the communication volume requirement information in the case of the request mode. The information used as the difference is not limited to the communication volume requirement information, and may also be other information (received signal quality information, received frame statistical information, transmitted frame statistical information, etc.).

[0150] So far, it has been described that, assuming that in a Multi-AP wireless communication system, a station device reports the results of measuring the signal quality of frames sent from surrounding access point devices to the access point device side, and the access point device side determines the combination of access point devices that perform coordination actions between access point devices based on the report content.

[0151] When the station device is an MLD, the signal quality of each of multiple frequencies (multi-link) can be measured. Fig.17 An example of the composition of the report frame 12-51 (also referred to as the report response frame 12-51) is shown in FIG. The access point device cooperation information is composed of a plurality of link quality information. Link quality information 1 is composed of information on link 1 (e.g., a frequency of 2.4 GHz band), link quality information 2 is composed of information on link 2 (e.g., a frequency of 5 GHz band), link quality information 3 is composed of information on link 3 (e.g., a frequency of 6 GHz band), and other plurality of link quality information that may be used by the MLD. Each link quality information is composed of identification information, received signal quality information, received frame statistical information, sent frame statistical information, communication volume requirement information, etc., but does not necessarily have to include all of the information. The identification information herein is set to be information for identifying the link (Link ID, etc.).

[0152] exist Fig.13 In the case where the SME of the station device issues the primitive MLME-MEASURESTA request to request measurement to the MLME, the MLME generates link quality information of multiple frequencies (multi-links) constituting the MLD or multiple frequencies (multi-links) that may be used in the MLD, and reports the link quality information to the access point device of the connection destination in the report frame 13-2. In addition, the content or a part of the access point device cooperation information included in the report frame 13-2 is reported to the SME in the primitive MLME-MEASURESTA confirmation, and the reported information can also be used by the upper layer. Here, the upper layer refers to a layer higher than the MAC layer, and the upper layer also includes the application layer. The upper layer can use the link quality information included in the received access point device cooperation information to determine which application is mapped to which link and which TID (Traffic ID) is mapped to (TID to Link Mapping) which link (frequency). The upper layer can use the received link quality information for coordination actions between access point devices.

[0153] Each application can also select a link corresponding to each service request for communication. For example, suppose that the communication status of link 1 is the best, and the signal quality of link 2 and link 3 deteriorates in order. For the expected bit rate of each application, if application 1 has the highest bit rate and it decreases in order of application 2 and application 3, by mapping application 1 to link 1, application 2 to link 2, and application 3 to link 3, it is possible to optimize all applications so that they can operate appropriately.

[0154] As another application, the measurement object can be set to the surrounding station devices instead of the surrounding access point devices. If the station device is extended in a manner to measure the signal quality of frames sent from other station devices, a certain station device can also be used for the selection and judgment of the best other station device for P2P communication, TDLS (Tunneled Direct Link Setup) communication, etc. as communication between station devices. [2. Common points in all embodiments]

[0155] The communication device of the present invention can communicate in a frequency band (spectrum) called an unlicensed band that does not require a license for use from a country or region, but the frequency band that can be used is not limited to this. The communication device of the present invention can also exert this effect in, for example, a frequency band called a white band that is actually not used for the purpose of preventing interference between frequencies, although a license for use of a specific service is granted from a country or region (for example, a frequency band that is allocated for television broadcasting but is not used depending on the region), and a shared spectrum (shared frequency band) that is expected to be shared by multiple operators.

[0156] The program that operates in the wireless communication device of the present invention is a program that controls the CPU (Central Processing Unit) and the like in a manner that realizes the functions of the above-mentioned embodiments of the present invention (a program that enables the computer to function). In addition, the information processed by these devices is temporarily stored in the RAM (Random Access Memory) when processing, and then stored in various ROMs (Read-Only Memory) and HDDs (Hard Disk Drives), and is read, modified, and written by the CPU as needed. The recording medium for storing the program may be any of a semiconductor medium (e.g., a ROM, a nonvolatile memory card, etc.), an optical recording medium (e.g., a DVD (Digital Video Disc), an MO (Magneto-Optica: a magneto-optical disk), an MD (Mini Disc: a mini magneto-optical disk), a CD (Compact Disk: a small laser disk), a BD (Blu-ray Disc: a blue-ray disc), etc.), a magnetic recording medium (e.g., a magnetic tape, a floppy disk, etc.), and the like. Furthermore, by executing the loaded program, not only the functions of the above-described embodiments are realized, but sometimes the functions of the present invention are realized by performing processing together with an operating system or other application programs based on instructions of the program.

[0157] In addition, when circulating in the market, the program can be stored in a removable recording medium to circulate it, or transmitted to a server computer connected via a network such as the Internet. In this case, the storage device of the server computer is also included in the present invention. In addition, part or all of the communication device of the above-mentioned embodiment can also be implemented as a typical integrated circuit, i.e., LSI. Each functional block of the communication device can be individually chip-based, or part or all of it can be integrated and chip-based. When each functional block is integrated into an integrated circuit, an integrated circuit control unit that controls them is attached.

[0158] Furthermore, the method of integrated circuitization is not limited to LSI, and can also be realized by a dedicated circuit or a general-purpose processor. Furthermore, when an integrated circuitization technology that replaces LSI emerges with the advancement of semiconductor technology, an integrated circuit based on this technology can also be used.

[0159] It should be noted that the invention of the present application is not limited to the above-mentioned implementation modes. The wireless communication device of the present application is not limited to the application to the mobile station device, and can also be applied to fixed or non-movable electronic devices installed indoors and outdoors, such as AV (Audio Video) equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, other life equipment, etc.

[0160] As mentioned above, the embodiment of the present invention has been described in detail with reference to the drawings, but the specific structure is not limited to the embodiment, and designs and the like that do not depart from the gist of the present invention are also included in the scope of the claims. Industrial Applicability

[0161] The present invention is applicable to a communication device and a communication method. Description of Reference Numerals 1-1, 1-2, 1-3, 1-4: Access point devices 2-1, 2-12, 2-13, 2-123, 2-2, 2-21, 2-23, 2-213, 2-3, 2-31, 2-32, 2-34, 2-312, 2-4: Station device 3-1, 3-2, 3-3, 3-4: Communication area (coverage) 10001-1: Upper Level 10002-1: Autonomous decentralized control unit 10002a-1: CCA Department 10002b-1: Retreat 10002c-1: Sending judgment unit 10003-1: Transmission Department 10003a-1: Physical layer frame generation unit 10003b-1: Wireless transmission unit 10004-1: Receiving Department 10004a-1: Wireless receiving unit 10004b-1: Signal demodulation unit 10005-1: Antenna 9-1, 9-2, 9-3, 9-4, 9-5, 9-6: Original language 11-1, 11-2, 11-3: Frame 12-1 to 12-14, 12-21 to 12-24, 12-31 to 12-34, 12-41 to 12-44, 12-51: Frame 13-1, 13-3, 13-4: Original language 14-1, 14-3, 14-4, 14-6, 14-7, 14-8: Original language 20000-1: MLD Access Point Device 13-2, 14-2, 14-5: Frame 20000-2, 20000-3, 20000-4: Sub-access point devices 30000-1: MLD station device 30000-2, 30000-3, 30000-4: Substation device

Claims

1. A station device, which is a station device for communicating with an access point device, characterized in that: Connecting with a first access point device, The station device comprises: a receiving unit, receiving frames sent by a plurality of access point devices including the first access point device; and The sending unit sends wireless management frames. The wireless management frame includes received signal quality information generated by taking each frame sent by the plurality of access point devices as a measurement object, In case of requesting the received signal quality information from the first access point device, sending the wireless management frame via a request frame, In a case where the received signal quality information is not requested from the first access point device, at least one of the first method and the second method is executed; The first method notifies the station management entity SME of the received signal quality information from the medium access control management entity MLME of the station device through a primitive, The second method sends the wireless management frame via an unsolicited frame.

2. The station device according to claim 1, characterized in that The execution of the first method and the second method is instructed by primitives from the SME of the station device to the MLME.

3. The station device according to claim 1, characterized in that The received signal quality information includes at least one of received signal strength indicators RSSI, signal-to-noise ratio SNR, signal-to-interference-plus-noise ratio SINR, and channel quality indicator CQI of the multiple access point devices.

4. The station device according to claim 1, characterized in that The received signal quality information includes capability information of the plurality of access point devices.

5. The station device according to claim 1, characterized in that: Contents of the received signal quality information included in the request frame are different from contents of the received signal quality information included in the non-request frame.

6. The station device according to claim 1, characterized in that: The received signal quality information includes upper layer communication volume requirement information.

7. An access point device, which is an access point device for communicating with a station device, characterized in that: Connect with the first station device, The access point device comprises: A sending unit that sends a frame; and The receiving part receives the frame. The access point device receives an unsolicited frame including received signal quality information sent by the first station device, The received signal quality information is generated by the first station device taking each frame transmitted by a plurality of access point devices including the connected access point device as a measurement target.

8. A communication method used in a communication system composed of a station device, a first access point device communicating with the station device, and one or more access point devices other than the first access point device, characterized in that: The station device is connected to a first access point device, The station device receives frames transmitted by a plurality of access point devices including a first access point device, The station device sends a wireless management frame, The wireless management frame includes received signal quality information generated by taking each frame sent by the plurality of access point devices as a measurement object, When the station device requests the received signal quality information from the first access point device, the station device transmits the wireless management frame using a request frame. The station device executes at least one of the first method and the second method when the station device does not request the received signal quality information from the first access point device. The first method notifies the received signal quality information from the medium access control management entity MLME to the station management entity SME through a primitive, The second method sends the wireless management frame via an unsolicited frame.

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