Wireless communication device and wireless communication method

Abstract

According to the invention, the communication quality of the wireless link in wireless communication can be well maintained. A station device (4002) is provided with a timer (5002-1), and when a radio frame (7003) requiring a response is received and a reception error is not detected, the station device (4002) transmits a probe frame (7005) following the transmission of an Ack frame (7004), which is a response frame to the radio frame (7003), and resets the timer (5002-1). Further, when the timer (5002-1) is in the expiration state (7104), the station device (4002) transmits the probe frame (7009) after the carrier sensing and backoff procedure, and resets the timer (5002-1).

Description

Technical Field

[0001] The present invention relates to a wireless communication device and a wireless communication method. Background Art

[0002] IEEE (The Institute of Electrical and Electronics Engineers Inc.) continues to work on updating the specifications of IEEE 802.11, which is the wireless LAN standard specification, in order to achieve faster wireless LAN (Local Area Network) communications and more efficient frequency utilization. In wireless LAN, wireless communications are carried out using frequency bands (unlicensed frequency bands) that can be used without permission (authorization) from the country / region. In personal use such as home, the wireless LAN access point function is included in the line terminal device for connecting to the WAN (Wide Area Network) line such as the Internet, or the wireless LAN access point device is connected to the line terminal device, etc., to make the Internet access from within the house wireless. As a result, wireless LAN station devices such as smartphones and personal computers can connect to the wireless LAN access point device and access the Internet.

[0003] In 2021, the specification of IEEE 802.11ax was completed, and wireless LAN devices that meet the specifications, smartphones equipped with the wireless LAN devices, personal computers and other communication devices were launched as Wi-Fi 6 (registered trademark, the name for IEEE 802.11ax standard products certified by Wi-Fi Alliance) corresponding products. In addition, currently, as the successor standard of IEEE 802.11ax, standardization activities for IEEE 802.11be are underway, and discussions on IEEE 802.11bn as the successor standard are also underway. With the rapid popularization of wireless LAN devices, in the recent IEEE802.11 standardization, research has been conducted to further improve the throughput of each user in an overly densely configured environment of wireless LAN devices.

[0004] In addition, in the IEEE 802.11be standardization, a discussion on multi-link operation (MLO) was conducted, in which a wireless communication device can use multiple frequency bands, channels, etc. at the same time and maintain multiple link connections to communicate (Non-Patent Document 1). As an example of MLO, three link connections of different frequency bands (frequency bands) can be listed, namely, a connection of a 2.4 GHz band, a connection of a 5 GHz band (5.2 GHz band, 5.3 GHz band, 5.6 GHz band, etc.), and a connection of a 6 GHz band. Of course, the combination of frequency bands, channels, etc. is not limited to this, and various combinations can be used. From the perspective of frequency bands, in the future, high frequency bands such as millimeter waves (28 GHz band, 45 GHz band, 60 GHz band, etc.) and (sub) terahertz waves (100 GHz to 300 GHz bands) can also be used as a link to constitute a multi-link. According to MLO, a wireless communication device can simultaneously maintain multiple link connections with different wireless resources used and communication settings. The wireless communication device can not only use multiple links to send and receive frames at the same time, but also switch the link connection for sending and receiving frames without reconnecting, that is, it can change the frequency band. It should be noted that the individual links constituting the multi-link here are also called physical layer links. In addition, the wireless communication device corresponding to MLO is called a multi-link device (MLD: Multi-Link Device). Prior art literature Non-patent literature

[0005] Non-patent document 1: IEEE 802.11-19 / 0773-08-00be, Nov. 2019 Summary of the invention Problem that the invention aims to solve

[0006] In wireless LANs, there is a problem of maintaining the communication quality of wireless links in order to achieve higher speeds and more efficient use of frequencies. Technical Solution

[0007] A wireless communication device and a wireless communication method of the present invention for solving the above-mentioned problems are as follows.

[0008] (1) That is, a wireless communication device according to one embodiment of the present invention is a wireless communication device that communicates with a wireless communication device of a communication partner using a wireless link, the wireless communication device comprising: a wireless communication unit that transmits and receives wireless frames in a first wireless link; and a wireless control unit that comprises a first timer, wherein when the wireless communication unit receives a wireless frame including first control information indicating setting of the first timer, the wireless control unit sets the first timer to an active state, and when a first wireless frame requiring a response is received in the first wireless link, the wireless communication unit transmits a first response frame to the first wireless frame, and then transmits a first detection frame without carrier sensing, and the wireless control unit resets the first timer, and when the first timer expires, the wireless communication unit transmits the first detection frame after performing carrier sensing in the first wireless link, and the wireless control unit resets the first timer.

[0009] (2) In addition, a wireless communication device according to an aspect of the present invention is a wireless communication device that communicates with a wireless communication device of a communication partner using multiple wireless links at the same time, wherein the multiple wireless links include the first wireless link and a second wireless link of a frequency band different from that of the first wireless link, wherein the wireless communication unit also transmits and receives wireless frames in the second wireless link, and the wireless control unit further includes a second timer, and when the wireless communication unit receives a wireless frame including second control information indicating setting of the second timer, the wireless control unit sets the second timer to an active state, and when a second wireless frame requiring a response is received in the second wireless link, the wireless communication unit transmits a second response frame to the second wireless frame, and then transmits a second detection frame without carrier sensing, and the wireless control unit resets the second timer, and when the second timer expires, the wireless communication unit transmits the second detection frame after performing carrier sensing in the second wireless link, and the wireless control unit resets the second timer.

[0010] (3) In the wireless communication device according to one aspect of the present invention, when the first timer reaches a predetermined value when the first wireless frame is received, the wireless communication unit transmits the first probe frame without carrier sense following transmission of the first response frame.

[0011] (4) In addition, in a wireless communication device of one embodiment of the present invention, when the first response frame is a block response frame, and when the number of affirmative responses included in the block response frame is less than a prescribed number, the wireless communication unit sends the first detection frame without carrier sensing following the sending of the block response frame.

[0012] (5) Furthermore, in the wireless communication device according to one aspect of the present invention, when the wireless communication unit receives a wireless frame including third control information, the wireless control unit sets an expiration condition of the first timer and resets the first timer.

[0013] (6) Furthermore, in the wireless communication device according to one aspect of the present invention, the third control information is information for setting quality of service QoS.

[0014] (7) Furthermore, in the wireless communication device according to one aspect of the present invention, when the wireless communication unit receives a wireless frame including fourth control information, the wireless control unit sets the first timer to a deactivated state.

[0015] (8) Furthermore, in the wireless communication device according to one aspect of the present invention, the fourth control information is information for canceling the setting of QoS.

[0016] (9) In addition, in a wireless communication device according to one embodiment of the present invention, the wireless control unit further includes a third timer. When the wireless communication unit receives a wireless frame including the first control information, the wireless control unit sets the first timer and the third timer to an activated state. When the third timer expires when the first wireless frame is received, the wireless communication unit sends the first detection frame without carrier sensing following the sending of the first response frame, and the wireless control unit resets the first timer and the third timer. When the first timer expires, the wireless communication unit sends the first detection frame after performing carrier sensing on the first wireless link, and the wireless control unit resets the first timer and the third timer.

[0017] (10) In addition, in a wireless communication device of one embodiment of the present invention, when the first timer reaches a specified value when the first wireless frame is received, the wireless communication unit sends the first detection frame without carrier sensing following the sending of the first response frame, and when the second timer reaches a specified value when the second wireless frame is received, the wireless communication unit sends the second detection frame without carrier sensing following the sending of the second response frame.

[0018] (11) In addition, in a wireless communication device of one embodiment of the present invention, when the first response frame or the second response frame is a block response frame, and when the number of affirmative responses included in the block response frame is less than a prescribed number, the wireless communication unit sends the first detection frame or the second detection frame without carrier sensing following the sending of the block response frame.

[0019] (12) In addition, in a wireless communication device of one embodiment of the present invention, when the wireless communication unit receives a wireless frame including third control information, the wireless control unit sets the expiration condition of the first timer and resets the first timer. When the wireless communication unit receives a wireless frame including fifth control information, the wireless control unit sets the expiration condition of the second timer and resets the second timer.

[0020] (13) In addition, in a wireless communication device of one embodiment of the present invention, when the wireless communication unit receives a wireless frame including fourth control information, the wireless control unit sets the first timer to a deactivated state, and when the wireless communication unit receives a wireless frame including sixth control information, the wireless control unit sets the second timer to a deactivated state.

[0021] (14) In addition, a wireless communication device according to one embodiment of the present invention is a wireless communication device that communicates with a wireless communication device of a communication partner using a wireless link, the wireless communication device comprising: a wireless communication unit that sends and receives wireless frames on a first wireless link; and a wireless control unit that generates control information, the wireless control unit generates first control information, the first control information including setting and resetting conditions related to a first timer possessed by the wireless communication device of the communication partner and sending conditions for a detection frame from the wireless communication device of the communication partner, the first wireless communication unit sends a wireless frame including the first control information.

[0022] (15) In addition, a communication method of one embodiment of the present invention is a communication method in a wireless communication device that uses a wireless link to communicate with other wireless communication devices, and the communication method comprises the following steps: receiving a wireless frame including first control information indicating the setting of a first timer; upon receiving the wireless frame including the first control information, setting the first timer to an activated state; receiving a first wireless frame requiring a response in a first wireless link; sending a first response frame to the first wireless frame; subsequently to sending the first response frame, sending a first detection frame without carrier sensing, and resetting the first timer; and when the first timer expires, sending the first detection frame in the first wireless link after performing carrier sensing, and resetting the first timer. Beneficial Effects

[0023] According to the wireless communication device and the wireless communication method of the present invention, the communication quality of the wireless link in wireless communication can be well maintained. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a diagram showing an example of a MAC layer frame structure of a wireless LAN system. Figure 2 This is a diagram showing an example of the PPDU structure of the wireless LAN system. Figure 3 FIG. 1 is a diagram showing an example of a detection process of a wireless LAN system. Figure 4 It is a diagram showing a configuration example of a communication system according to one aspect of the present invention. Figure 5 This is a block diagram showing a configuration example of a station device according to one aspect of the present invention. Figure 6 This is a block diagram showing a configuration example of an access point device according to one aspect of the present invention. Figure 7 This is a diagram showing an example of a detection process of a wireless communication system according to one embodiment of the present invention. Figure 8 This is a diagram showing an example of a detection process of a wireless communication system according to one embodiment of the present invention. Fig. 9 This is a flowchart of an example of a detection process of a station device according to one embodiment of the present invention. Fig.10 It is a diagram showing a configuration example of a communication system according to one aspect of the present invention. DETAILED DESCRIPTION

[0025] The wireless communication system in this embodiment includes an access point device (also referred to as AP, base station device) and a plurality of station devices (also referred to as STA, terminal devices). In addition, the communication system and network composed of the access point device and the station device are referred to as a basic service set (BSS: Basic Service Set, management scope). 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 or a wireless communication device is described, the communication device or the wireless communication device can represent both an access point device and a station device.

[0026] The access point device and the station device within the BSS communicate based on CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance). In the present embodiment, the infrastructure mode (infrastructure mode) in which the access point device communicates with multiple station 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 station devices communicate directly with each other. In the ad hoc mode, a station device replaces the access point 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 station device that forms the IBSS in the ad hoc mode can also be regarded as an access point device. The method of the present embodiment can also be implemented by Wi-Fi Direct (registered trademark) for direct communication between station devices. In Wi-Fi Direct, a station device replaces the access point device to form a group. The station device is called the group owner and can also be regarded as an access point device.

[0027] In the IEEE 802.11 system, each device can send multiple types of frames (communication frames) with a common frame format. Frames are defined by the physical (PHY: Physical) layer, the medium access control (MAC: Medium Access Control) layer, and the logical link control (LLC: Logical Link Control) layer.

[0028] The frame of the PHY layer is also called a physical protocol data unit (PPDU: PHY Protocol Data Unit, physical layer frame). The PPDU is composed of a physical layer header (PHY header) including information for signal processing at the physical layer, and a physical service data unit (PSDU: PHY Service Data Unit) as a data unit processed at the physical layer. The PSDU can be composed of an aggregated MPDU (A-MPDU: Aggregated MPDU) including multiple MAC protocol data units (MPDU: MAC Protocol Data Unit, MAC layer frame) as a retransmission unit in a wireless section.

[0029] The PHY header includes reference signals such as a short training field (STF: Short Training Field) for signal detection / synchronization, a long training field (LTF: Long Training Field) for obtaining channel information for data demodulation, and control signals such as a signal (SIG: Signal) including control information for data demodulation. In addition, according to the corresponding standards, STF is classified into legacy STF (Legacy-STF: L-STF), high throughput STF (High Throughput-STF: HT-STF), very high throughput STF (Very High Throughput-STF: VHT-STF), high efficiency STF (High Efficiency-STF: HE-STF), extremely high throughput STF (Extremely High Throughput-STF: EHT-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.

[0030] Furthermore, the PHY header may include information identifying the BSS of the transmission source of the frame (hereinafter also referred to as BSS identification information). The information identifying the BSS may be, for example, the SSID (Service Set IDentifier) ​​of the BSS and the MAC address of the access point device of the BSS. In addition, the information identifying the BSS may be a value inherent to the BSS other than the SSID and MAC address (e.g., BSS Color, etc.). Information indicating the BSS color may be included in the HE-SIG-A or U-SIG.

[0031] The PPDU is modulated according to the corresponding standard. For example, if it is the IEEE 802.11n standard, it is modulated into an Orthogonal Frequency Division Multiplexing (OFDM) signal.

[0032] The MPDU is composed of a MAC header including information for signal processing at the MAC layer, a MAC service data unit (MSDU) or a frame body which is a data unit processed at the MAC layer, and a frame check unit (FCS) for checking whether there is an error in the frame. Figure 1 ). In addition, multiple MSDUs can also be aggregated into an aggregated MSDU (A-MSDU: Aggregated MSDU).

[0033] The frame types of the MAC layer are divided into three categories: management frames, which manage the connection status between devices, etc.; control frames, which manage the communication status between devices; and data frames, which include the actual transmission data, each of which can be further classified into multiple subframe types. Control frames include acknowledgment response (Ack or ACK: Acknowledgement) frames, block acknowledgment response (BA or BlockAck: Block Acknowledgement) frames, request to send (RTS: Request To Send) frames, and clear to send (CTS: Clear To Send) frames. Block Ack can implement acknowledgment responses (receive completion notifications) for multiple MPDUs. Management frames include beacon frames, probe request frames, probe response frames, authentication frames, association request frames, and association response frames. Data frames include data frames, polling (CF-poll) frames, etc. Each device can identify the frame type and subframe type of the received frame by reading the content of the frame control field included in the MAC header.

[0034] The beacon frame includes a field indicating the period of sending beacons (Beacon interval) and SSID (Field). Access point devices can periodically broadcast beacon frames in the BSS, and station devices can identify surrounding access point devices by receiving beacon frames. Identifying access point devices based on beacon frames broadcast from access point devices by station devices is called passive scanning. On the other hand, detecting access point devices by broadcasting probe request frames in the BSS by station devices is called active scanning. The access point device can send a probe response frame as a response to the probe request frame, and the content of the probe response frame is the same as the content of the beacon frame.

[0035] After the station device identifies the access point device, it performs connection processing on the access point device. The connection processing is classified into an authentication process and an association process. The station device sends an authentication request frame to the access point device to which it wishes to connect. When the access point device receives the authentication request frame, it sends an authentication response frame including a status code indicating whether the station device can be authenticated to the station device. The station device determines whether the device itself is allowed to request authentication by the access point device by reading the status code included in the authentication response frame. It should be noted that the access point device and the station device can exchange authentication request frames and authentication response frames (both of which are also referred to as authentication frames) multiple times.

[0036] The station device continues the authentication process and sends a connection request frame to perform the connection process with the access point device. When the access point device receives the connection request frame, it determines whether to allow the connection of the station device and sends a connection response frame to notify the situation. In addition to the status code indicating whether the connection process can be performed, the connection response frame also includes an association identifier (AID: Association IDentifier) ​​for identifying the station device. The access point device can manage multiple station devices by setting different AIDs for the station devices that issue permission to connect.

[0037] After the connection process is completed, the access point device and the station device perform actual data transmission. In the IEEE802.11 system, as a media access method, the distributed coordination function (DCF), the point coordination function (PCF), and the extended hybrid coordination function (HCF) are defined. In HCF, as a specific implementation method, the extended distributed channel access (EDCA) and the HCF controlled channel access (HCCA) are defined.

[0038] First, based on DCF, an example of the action when the access point device sends a signal to the station device is described. In DCF, the access point device and the station device perform carrier sense (CS: Carrier Sense) to confirm the use status of the wireless channel around the device itself before communication. For example, during the period of carrier sense performed by the access point device and the station device before sending the frame, if a signal with a reception power higher than the preset clear channel assessment level (CCA level: Clear Channel Assessment level) is received in the wireless channel, the transmission of the frame in the wireless channel is postponed. Hereinafter, in the wireless channel, the state in which a signal with a reception power higher than the CCA level is detected is referred to as a busy state, and the state in which a signal with a reception power higher than the CCA level is not detected is referred to as an idle state. In this way, the CS performed based on the power level of the signal actually received by each device 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 (CCAT: CCA Threshold). It should be noted that, when the access point device and the station device detect a signal with a reception power equal to or higher than the CCA level, they at least enter an operation of demodulating the signal at the PHY layer.

[0039] The access point device performs carrier sensing during the period of the inter-frame space (IFS) set according to the type of the frame to be sent, and determines whether the wireless channel is busy or idle. The period during which the access point device performs carrier sensing varies depending on the frame type and subframe type of the frame to be sent by the access point device. In the IEEE 802.11 system, multiple IFSs with different periods are defined, including a short inter-frame space (SIFS) for frames with the highest priority, a polling inter-frame space (PIFS) for frames with relatively high priority, and a distributed de-inter-frame space (DIFS) for frames with low priority. When sending data frames via DCF, the access point device uses DIFS.

[0040] After the access point device waits for the DIFS period, it further waits for a random backoff time to prevent frame collisions. In the IEEE 802.11 system, a random backoff time based on a contention window (CW: Contention Window) is used. In CSMA / CA, it is assumed that a frame sent by a certain sending station is received by a receiving station without interference from other sending stations. Therefore, when multiple sending stations send frames at the same timing, a conflict occurs between frames, and the receiving station may not be able to receive them accurately. Therefore, each sending station waits for a randomly set time before starting to send, thereby avoiding frame collisions. When it is determined by carrier sensing that the wireless channel is in an idle state, the access point device can start the countdown of the backoff counter set based on the CW, the backoff counter becomes 0 and the transmission right is obtained for the first time, and the frame is sent to the station device. It should be noted that during the countdown of the backoff counter, if the access point device determines that the wireless channel is in a busy state through carrier sensing, the countdown of the backoff counter is stopped. Then, when the wireless channel becomes idle again, the access point device continues to wait for the same period as the previous IFS and restarts the remaining countdown of the previous backoff counter.

[0041] The station device as a receiving station receives the frame, reads the PHY header of the frame, and demodulates the received frame. Then, the station device can 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 station device can also determine the destination of the frame based on the information included in the PHY header (for example, the group identifier (GID: Group Identifier, Group ID) included in the VHT-SIG-A).

[0042] When the station 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 access point device as the sending station. The Ack frame is one of the highest priority frames that is sent only during the SIFS period of standby (without taking the random backoff time). The access point device ends a series of communications by receiving the Ack frame sent from the station device. It should be noted that if the station device cannot accurately receive the frame, the station device does not send the Ack frame. Therefore, if the access point device does not receive the Ack frame from the receiving station (station device) within a certain period of time (SIFS+Ack frame length) after the frame is sent, it determines that the communication has failed and ends the communication. In this way, the end of a communication (also called a burst) of the IEEE802.11 system must be determined by the reception of the Ack frame, except for special cases such as sending broadcast signals such as beacon frames and using fragments to divide the sent data.

[0043] When the station 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 included in the PHY header, etc. The station device does not attempt to send during the period set to NAV. That is, the station device performs the same action as when the wireless channel is judged to be busy through the physical CS during the period set to NAV, so the communication control based on NAV is also called virtual carrier sensing (virtual CS). In addition to the case of setting based on the information included in the PHY header, NAV is also set by the RTS frame and CTS frame introduced to eliminate the hidden terminal problem.

[0044] Next, an example of the operation when the access point device sends a signal to the station device is described based on PCF. Unlike DCF, where each device performs carrier sensing and autonomously obtains the transmission right, in PCF, a control station called point coordination (PC: Point Coordinator) controls the transmission right of each device in the BSS. Usually, the access point device is a PC, which obtains the transmission right of the station device in the BSS.

[0045] 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 access point device as the PC broadcasts a beacon frame including information such as the CFP period (CFP Maxduration: CFP maximum duration) 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 beginning of the transmission of the PCF, and it is transmitted without waiting for CW. The station device that receives the beacon frame sets the CFP maximum duration included in the beacon frame to NAV. After that, until the period set to NAV has passed or a signal (such as a data frame including CF-end) is received to broadcast the end of the CFP to the BSS, the station device can obtain the transmission right only when a signal (such as a data frame including CF-poll) is received from the PC to notify the device itself to obtain the transmission right through signaling. It should be noted that, in the CFP period, no collision of data packets occurs in the same BSS, so each station device does not use the random backoff time used in DCF.

[0046] The wireless communication device has either or both of a function of transmitting PPDU and a function of receiving PPDU. Figure 2: This is a diagram showing an example of the PPDU structure sent by a wireless communication device. The PPDU corresponding to the IEEE 802.11a / g standard is a structure including L-STF, L-LTF, L-SIG and data frame (MAC frame, payload, data part, data, information bit, etc.). The PPDU corresponding to the IEEE 802.11n standard is a structure including L-STF, L-LTF, L-SIG, HT-SIG, HT-STF, HT-LTF and data frame. The PPDU corresponding to the IEEE 802.11ac standard is a structure including L-STF, L-LTF, L-SIG, VHT-SIG-A, VHT-STF, VHT-LTF, VHT-SIG-B and part or all of the data frame. The PPDU corresponding to the IEEE 802.11ax 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 the IEEE 802.11be standardization 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.

[0047] Depend on Figure 2 The L-STF, L-LTF, and L-SIG surrounded by the dotted lines in the figure are common structures in the IEEE 802.11 standard (hereinafter, L-STF, L-LTF, and L-SIG are also collectively referred to as L-header). For example, a wireless communication device corresponding to the IEEE 802.11a / g standard can receive the L-header in the PPDU corresponding to the IEEE 802.11n / ac / ax / be standard. A wireless communication device corresponding to the IEEE802.11a / g standard can receive the PPDU corresponding to the IEEE 802.11n / ac / ax / be standard as the PPDU corresponding to the IEEE 802.11a / g standard.

[0048] However, wireless communication devices corresponding to the IEEE 802.11a / g standard cannot demodulate the PPDU corresponding to the IEEE802.11n / ac / ax / be standard after the L-header, and therefore cannot demodulate information related to the sender address (TA: TransmitterAddress), receiver address (RA: Receiver Address), Duration / ID field, etc.

[0049] IEEE 802.11 specifies a method for inserting duration information into L-SIG so that wireless communication devices that comply with IEEE 802.11a / g standards can 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 comply with IEEE 802.11a / g standards.

[0050] The wireless communication device can send L-SIG multiple times (L-SIG repetition). In this case, the wireless communication device on the receiving side can receive the L-SIG sent multiple times by using maximum ratio combining (MRC) to improve the demodulation accuracy of L-SIG. Moreover, when the wireless communication device accurately receives the L-SIG through MRC, it can interpret that the PPDU including the L-SIG is a PPDU corresponding to the IEEE 802.11ax or IEEE 802.11be standard.

[0051] 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, PHY header, etc. specified by IEEE 802.11) 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 a portion or all of the destination address, the transmission source address, the PPDU, or the information related to the data period.

[0052] 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.

[0053] Figure 3 FIG. 1 is a diagram showing an example of a sounding process for the purpose of channel estimation of a wireless communication path in IEEE 802.11ax. Figure 3In one example, first, the access point device (AP) sends a Null Data PPDU (NDP) announcement frame 3001 indicating information of the station device (STA) that is the target of the sounding to be performed (as the recipient of the sounding frame), the type of specified feedback information, etc. Then, the access point device sends an NDP frame 3002 including a training field for channel estimation from the NDP announcement frame after a SIFS period. The station device performs channel estimation based on the received NDP frame 3002, and sends a frame such as a Compressed Beamforming / CQI frame 3003 that feeds back the channel estimation result to the access point device from the NDP frame 3002 after a SIFS period. [1. First embodiment]

[0054] Figure 44002-1 to 4002-3. It should be noted that the wireless communication device 4001-1 is also referred to as the access point device 4001-1, and the wireless communication devices 4002-1 to 4002-3 are also referred to as station devices 4002-1 to 3. In addition, the wireless communication devices 4002-1 to 4002-3 (station devices 4002-1 to 4002-3) are also referred to as wireless communication devices 4002A (station devices 4002A) as devices connected to the wireless communication device 4001-1. The wireless communication device 4001-1 and the wireless communication device 4002A are wirelessly connected and are in a state where they can send and receive PPDUs to each other. In addition, the wireless communication system of this embodiment may also include a wireless communication system 4003-2 in addition to the wireless communication system 4003-1. The wireless communication system 4003-2 includes a wireless communication device 4001-2 and wireless communication devices 4002-4 to 4002-6. It should be noted that the wireless communication device 4001-2 is also referred to as an access point device 4001-2, and the wireless communication devices 4002-4 to 4002-6 are also referred to as station devices 4002-4 to 4002-6. In addition, the wireless communication devices 4002-4 to 4002-6 (station devices 4002-4 to 4002-6) are also referred to as wireless communication devices 4002B (station devices 4002B) as devices connected to the wireless communication device 4001-2. Furthermore, the wireless communication device 4001-1 and the wireless communication device 4001-2 (access point devices 4001-1 and 4001-6) are also referred to as the wireless communication device 4001 (access point device 4001) when they are not identified separately and explained, and the wireless communication devices 4002-1 to 4002-6 (station devices 4002-1 to 4002-6) are also referred to as the wireless communication device 4002 (station device 4002) when they are not identified separately and explained. The wireless communication system 4003-1 and the wireless communication system 4003-2 form different BSSs, but this does not necessarily mean that the ESS (Extended Service Set) representing the service set forming the LAN (Local Area Network) is different. That is, the wireless communication devices belonging to the same ESS can be regarded as belonging to the same network by the upper layer. In addition, the BSS is combined via the DS (Distribution System) to form the ESS. It should be noted that the wireless communication systems 4003-1 and 4003-2 can also each have a plurality of wireless communication devices.

[0055] Figure 51 is a diagram showing an example of the configuration of the station device 4002. The station device 4002 is configured to include a wireless control unit (wireless control step) 5001, a timer unit (timer step) 5002, a wireless communication unit (wireless communication step) 5003, and an antenna unit 5004. Furthermore, the wireless communication unit 5003 is configured to include a physical layer frame generation unit (physical layer frame generation step) 5003a, a wireless transmission unit (wireless transmission step) 5003b, a wireless reception unit (wireless reception step) 5003c, a reception power measurement unit (reception power measurement step) 5003d, a channel estimation unit (channel estimation step) 5003e, and a signal demodulation unit (signal demodulation step) 5003f.

[0056] The wireless control unit 5001 performs information processing on layers higher than the physical layer, such as the MAC layer and LLC layer, on information processed within the wireless communication device itself (information related to the transmitted frames, MIB (Management Information Base), etc.) and frames received from other wireless communication devices, and controls the wireless communication unit 5003.

[0057] The timer unit 5002 includes one or more timers and manages the timers related to the detection process. The details of the timer unit 5002 will be described later. Figure 5 In an example, the timer unit 5002 is described as being included in the wireless control unit 5001, but the invention is not limited to this configuration and may be provided outside the wireless control unit 5001 and configured to operate under the control from the wireless control unit 5001.

[0058] The physical layer frame generation unit 5003a has a function of generating a physical layer frame (PPDU). The physical layer frame generation unit 5003a performs error correction coding, modulation, beamforming processing (precoding processing), etc. on the MAC layer frame transmitted from the wireless control unit 5001. The beamforming processing is realized by multiplying the modulated signal by the beamforming matrix (beamforming filter) notified from the wireless control unit 5001. The physical layer frame generation unit 5003a outputs the generated physical layer frame to the wireless transmission unit 5003b.

[0059] The wireless transmission unit 5003b converts the physical layer frame input from the physical layer frame generation unit 5003a into a signal of a radio frequency band (Radio Frequency: RF) to generate a wireless signal. The processing performed by the wireless transmission unit 5003b includes digital-analog conversion, filtering, frequency conversion from baseband frequency to radio frequency, etc. The wireless transmission unit 5003b transmits the generated wireless signal through the antenna unit 5004.

[0060] The wireless receiving unit 5003c has a function of converting a wireless signal received by the antenna unit 5004 into a baseband signal and generating a physical layer signal (e.g., a physical layer frame). The processing performed by the wireless receiving unit 5003c includes frequency conversion processing from a wireless frequency to a baseband frequency, filtering, analog-to-digital conversion, etc. The physical layer signal, which is a received signal converted into a digital signal by the wireless receiving unit 5003c, is input to the received power measuring unit 5003d, the channel estimating unit 5003e, and the signal demodulating unit 5003f.

[0061] The received power measuring unit 5003d measures the received power of the received signal input from the wireless receiving unit 5003c. The received power measuring unit 5003d can measure the received power related to the radio wave received by the frequency channel of the measurement object, the received power of the LTF of the received physical layer frame, etc. The received power measuring unit 5003d can notify the wireless control unit 5001 of the measurement result of the received power.

[0062] The channel estimation unit 5003e estimates the channel state transmitted by the physical layer frame based on the received signal of the LTF (L-LTF, HT-LTF, VHT-LTF, HE-LTF, etc.) included in the physical layer frame received by the wireless reception unit 5003c. The channel estimation unit 5003e can notify the signal demodulation unit 5003f and the wireless control unit 5001 of the channel estimation result.

[0063] The signal demodulation unit 5003f performs channel equalization, demodulation, error correction decoding, etc. on the physical layer frame received by the wireless receiving unit 5003c, and obtains information such as the PHY header and the MAC layer frame. The channel estimation result of the channel estimation unit 5003e can be used in the channel equalization process. The signal demodulation unit 5003f outputs the obtained PHY header and MAC layer frame to the wireless control unit 5001.

[0064] The wireless control unit 5001 can perform physical carrier sensing and virtual carrier sensing based on the received power measurement result of the received power measurement unit 5003d and the information obtained by the signal demodulation unit 5003f, and judge the state of the wireless channel (including whether it is idle or busy). The wireless control unit 5001 can notify the wireless communication unit 5003 of the wireless channel state judgment information.

[0065] When there is control information, data, etc. that want to be sent, the wireless control unit 5001 can use the state judgment information of the wireless channel to start the backoff process. The wireless control unit 5001 generates a backoff counter based on the CW and has a countdown function of the backoff counter. For example, when the state judgment information of the wireless channel indicates an idle state, the wireless control unit 5001 can execute the countdown of the backoff counter, and when the state judgment information of the wireless channel indicates a busy state, the wireless control unit 5001 can stop the countdown of the backoff counter. In addition, the wireless control unit 5001 uses either or both of the state judgment information of the wireless channel or the value of the backoff counter to make a transmission judgment. For example, when the state judgment information of the wireless channel indicates an idle state and the value of the backoff counter is 0, the wireless control unit 5001 can notify the wireless communication unit 5003 of the transmission judgment information. In addition, when the state judgment information of the wireless resource indicates an idle state, the wireless control unit 5001 can notify the wireless communication unit 5003 of the transmission judgment information.

[0066] Figure 6 1 is a diagram showing an example of the configuration of the access point device 4001. The access point device 4001 is configured to include a wireless control unit (wireless control step) 6001, a wireless communication unit (wireless communication step) 5003, and an antenna unit 5004. Furthermore, the wireless communication unit 5003 is configured to include a physical layer frame generation unit (physical layer frame generation step) 5003a, a wireless transmission unit (wireless transmission step) 5003b, a wireless reception unit (wireless reception step) 5003c, a reception power measurement unit (reception power measurement step) 5003d, a channel estimation unit (channel estimation step) 5003e, and a signal demodulation unit (signal demodulation step) 5003f. Figure 6 The access point device 4001 is also basically the same as Figure 5 Therefore, the following description will focus on the differences between the two, and the description of the same parts will be omitted. Figure 5 The corresponding parts of the station devices are marked with the same figure marks for explanation.

[0067] The wireless control unit 6001 performs information processing at layers higher than the physical layer, such as the MAC layer and LLC layer, on information processed within the wireless communication device itself (information related to the transmitted frames, MIB (Management Information Base) etc.) and frames received from other wireless communication devices, and controls the wireless communication unit 5003.

[0068] The physical layer frame generation unit 5003a has a function of generating a physical layer frame (PPDU). The physical layer frame generation unit 5003a performs error correction coding, modulation, beamforming processing (precoding processing), etc. on the MAC layer frame transmitted from the wireless control unit 6001. The beamforming processing is realized by multiplying the modulated signal by the beamforming matrix (beamforming filter) notified from the wireless control unit 6001. The physical layer frame generation unit 5003a outputs the generated physical layer frame to the wireless transmission unit 5003b.

[0069] The received power measuring unit 5003d measures the received power of the received signal input from the wireless receiving unit 5003c. The received power measuring unit 5003d can measure the received power related to the radio wave received by the frequency channel of the measurement object, the received power of the LTF (L-LTF, HT-LTF, VHT-LTF, HE-LTF, etc.) of the received physical layer frame, etc. The received power measuring unit 5003d can notify the wireless control unit 6001 of the measurement result of the received power.

[0070] The channel estimation unit 5003e estimates the channel state transmitted by the physical layer frame based on the received signal of the LTF included in the physical layer frame received by the wireless reception unit 5003c. The channel estimation unit 5003e can notify the signal demodulation unit 5003f and the wireless control unit 6001 of the channel estimation result.

[0071] The signal demodulation unit 5003f performs channel equalization, demodulation, error correction decoding, etc. on the physical layer frame received by the wireless receiving unit 5003c, and obtains information such as the PHY header and the MAC layer frame. The channel estimation result of the channel estimation unit 5003e can be used in the channel equalization process. The signal demodulation unit 5003f outputs the obtained PHY header and MAC layer frame to the wireless control unit 6001.

[0072] When there is control information, data, beacon, etc. that want to be sent, the wireless control unit 6001 can use the state judgment information of the wireless channel to start the backoff process. The wireless control unit 6001 generates a backoff counter based on the CW and has a countdown function of the backoff counter. For example, when the state judgment information of the wireless channel indicates an idle state, the wireless control unit 6001 can execute the countdown of the backoff counter, and when the state judgment information of the wireless channel indicates a busy state, the wireless control unit 6001 can stop the countdown of the backoff counter. In addition, the wireless control unit 6001 uses either or both of the state judgment information of the wireless channel or the value of the backoff counter to make a transmission judgment. For example, when the state judgment information of the wireless channel indicates an idle state and the value of the backoff counter is 0, the wireless control unit 6001 can notify the wireless communication unit 5003 of the transmission judgment information. In addition, when the state judgment information of the wireless resource indicates an idle state, the wireless control unit 6001 can notify the wireless communication unit 5003 of the transmission judgment information.

[0073] Figure 7 FIG. 1 is a diagram showing an example of a detection process of a wireless communication system according to the present embodiment. Figure 7 In FIG. 4 , it is assumed that a wireless link (first wireless link) has been established between the access point device 4001 and the station device 4002, and an example of a communication flow in the wireless link is shown on the left, and an example of a state transition of a timer 5002-1 (also referred to as a first timer) provided in the timer unit 5002 of the station device 4002 is shown on the right. Figure 7 In the example, timer 5002-1 is initially in a deactivated state (7101).

[0074] The access point device 4001 generates setting information related to the timer 5002-1 provided in the station device 4002 and control information (first control information) including a detection frame transmission condition from the station device 4002, and transmits a wireless frame 7001 including the control information to the station device 4002. The setting information related to the timer 5002-1 may include a timer count initial value, a timer count expiration value, timer activation indication information, timer reset indication information, timer reset timing information, and the like.

[0075] The station device 4002 that receives the wireless frame 7001 including the first control information obtains the first control information included in the wireless frame 7001, and activates (7002) after setting the timer count initial value of the timer 5002-1 according to the first control information. By activating 7002, the timer 5002-1 is reset to the timer count initial value, and moves from the deactivated state 7101 to the activated state 7102, and the countdown operation begins. While in the activated state, the timer 5002-1 continues to count down. It should be noted that in Figure 7 In the figure, an example of simultaneously executing the setting, resetting, activating, and starting the countdown of the timer 5002-1 through the reception of the wireless frame 7001 is described, but it is not limited to this. For example, other wireless frames (the control information included therein) can also be triggered separately to execute the setting and resetting of the timer count initial value, activation, and the start of the countdown.

[0076] In addition, Figure 7 In the description, the timer 5002-1 is assumed to be a countdown timer, and the count becomes a preset timer initial value by being reset, and the example of the expiration state when the count reaches 0 is described, but the present invention is not limited to this. For example, the timer expiration value may be set to other than 0. Alternatively, the timer 5002-1 may be configured as an up-counting timer, and is initialized to count 0 by being reset, and becomes the expiration state when the count reaches the preset timer expiration value.

[0077] When the station device 4002 receives the wireless frame (first wireless frame) 7003 that requires a response and no error is detected in the wireless frame 7003, it sends an Ack frame 7004 as a response frame to the wireless frame 7003, and then sends a detection frame 7005 (hereinafter, the detection frame sent through the first wireless link will also be referred to as the first detection frame), and resets the timer 5002-1 to the timer count initial value (7006). The reset timer 5002-1 continues to be activated (7103) and counts down from the timer count initial value. It should be noted that the timing of resetting (7006) the timer 5002-1 is not limited to the time when the detection frame 7005 is sent, and can be set within a range where the effect remains unchanged, such as between the timing of sending the Ack frame 7004 and the timing of sending the detection frame 7005.

[0078] The wireless frame that needs a response is not limited to a data frame, and may be a frame including control information that needs a response. The sending of the Ack frame 7004 and the sending of the probe frame 7005 are preferably performed at an interval of SIFS, but are not limited thereto, and other IFSs used in the case of high priority may also be used. Moreover, the Ack frame and the probe frame may be connected and sent. In addition, a frame that combines the Ack frame and the probe frame may be redefined and sent.

[0079] When receiving the wireless frame 7003, the transmission of the probe frame 7005 can be implemented to reset the timer 5002-1 only when the count of the timer 5002-1 reaches the specified value (below the specified value). In this case, when the timer 5002-1 does not reach the specified value, that is, the time elapsed from the last transmission of the probe frame is less than the specified time, the transmission of the probe frame can be suppressed, and the overhead generated by the transmission of the probe frame can be reduced.

[0080] The radio frame 7003 may be a data frame for transmitting an A-MPDU that aggregates multiple MPDUs, and the Ack frame may be a block Ack frame. When the block Ack frame is used, the transmission of the probe frame 7005 may be implemented to reset the timer 5002-1 only when the number or ratio of positive responses included in the block Ack is less than a specified value. In this case, when the timer 5002-1 is not in the expired state, the transmission of the probe frame can be suppressed when the state of the radio link is good, thereby reducing the overhead generated by the transmission of the probe frame.

[0081] When the count of timer 5002-1 is 0 and in the expired state (7104), station device 4002 enters the transmission standby state of the detection frame (7007). When timer 5002-1 expires, station device 4002 performs carrier sensing and confirms that the wireless channel is idle, and then starts the backoff process (7008). During the backoff period, when the wireless channel is idle, station device 4002 transmits detection frame 7009 and resets timer 5002-1 (7010). Timer 5002-1 is reset to the timer count initial value and transitions to the active state, and starts the countdown operation (7105).

[0082] When receiving the radio frame 7011 including the control information (fourth control information) including the information on the setting release of the timer 5002-1, the station device 4002 deactivates the timer 5002-1 (7012). The deactivated timer 5002-1 stops the countdown operation and transitions to the deactivated state 7106.

[0083] The probe frames 7005 and 7009 may be a set of, for example, an NDP frame or an NDP announcement frame and an NDP frame, but are not limited thereto, and any frame may be configured to include a signal that can estimate the channel between the station device 4002 and the access point device 4001 .

[0084] The access point device 4001 that receives the sounding frames 7005 and 7009 from the station device 4002 can, for example, estimate the channel between the station device 4002 and the access point device 4001 based on the received sounding frames, and calculate the channel matrix, beamforming matrix (beamforming filter), etc.

[0085] Furthermore, as a modified example, when the first control information is not directly received from the access point device 4001 but other control information (third control information) is received, information equivalent to the first control information may be generated in the station device 4002 based on the received control information. As an example, when receiving setting information related to QoS (Quality of Service), the station device 4002 may activate (7002) after setting the timer count initial value of the timer 5002-1. The station device 4002 may change the timer count initial value according to the condition requested as QoS. When the allowed delay time is set to be short, the timer count initial value may be reduced. In addition, when the bit rate guarantee is set, the timer count initial value may also be reduced. In addition, the station device 4002 may set the timer count initial value of the timer 5002-1 based on the capability information exchanged with the access point device 4001. The setting of QoS may be set by the access point device 4001 according to the current traffic status or according to the application executed on the network. In addition, an application executed on the network can obtain QoS settings via the access point device 4002.

[0086] In addition, as a modified example, when the fourth control information is not directly received from the access point device 4001 but other control information is received, information equivalent to the fourth control information may be generated in the station device 4002 based on the received control information. As an example, when the setting information related to QoS is received, the station device 4002 may deactivate the timer 5002-1 (7012). When the allowed delay time is set to be long, the timer 5002-1 may be deactivated. In addition, when the setting of the bit rate is set to best effort, the timer 5002-1 may be deactivated.

[0087] Furthermore, as a modification, Figure 8FIG. 4 shows an example of a detection process in which the timer unit 5002 of the station device 4002 includes a timer 5002-2 (also referred to as a third timer) in addition to the timer 5002-1 (first timer). Figure 7 The following description will focus on the differences of an example of the detection process in FIG. 1 and omit the description of the same parts. Figure 7 Corresponding places are denoted by the same reference numerals for explanation.

[0088] exist Figure 8 In FIG. 1 , it is assumed that the wireless link (first wireless link) between the access point device 4001 and the station device 4002 has been established, and an example of the communication flow in the wireless link is shown on the left, and an example of the state transition of the timer 5002-1 and the timer 5002-2 of the timer unit 5002 of the station device 4002 is shown on the right. Figure 8 In the example, timer 5002-1 and timer 5002-2 are initially in a deactivated state (7101, 7201).

[0089] and Figure 7 Unlike the example of , the first control information included in the radio frame 7001 transmitted by the access point device 4001 to the station device 4002 includes, in addition to the setting information related to the timer 5002-1, the detection frame transmission condition from the station device 4002, etc., the setting information related to the timer 5002-2 is generated, and the radio frame 7001 including the control information is transmitted to the station device 4002. The setting information related to the timer 5002-1 and the timer 5002-2 may include the timer count initial value, the timer count expiration value, the timer activation indication information, the timer reset indication information, the timer reset timing information, etc. related to each timer. Here, each setting information may be selected so that the time until the timer in the timer 5002-2 expires is shorter than the time (count) until the timer in the timer 5002-1 expires.

[0090] The station device 4002 that receives the wireless frame 7001 including the first control information obtains the first control information included in the wireless frame 7001, and after setting the timer count initial values ​​of the timer 5002-1 and the timer 5002-2 according to the first control information, activates the two timers (7002, 7202). By activating 7002, the timer 5002-1 and the timer 5002-2 are reset to the timer count initial values, and migrate from the deactivated state 7101 and the deactivated state 7201 to the activated state 7102 and the activated state 7202 respectively, and the countdown action begins. While in the activated state, the timer 5002-1 and the timer 5002-2 continue to count down. It should be noted that in Figure 8 In the figure, an example of simultaneously executing the setting, resetting, activating, and starting the countdown of the timer count initial value of timer 5002-1 and timer 5002-2 through the reception of wireless frame 7001 is described, but it is not limited to this. For example, other wireless frames (the control information included therein) can also be triggered separately to execute the setting and resetting of the timer count initial value, activation, and starting the countdown.

[0091] In addition, Figure 8 In the description, the timer 5002-1 and the timer 5002-2 are assumed to be countdown timers, and the count becomes a preset timer count initial value by resetting, and the example of the expiration state when the count reaches 0 is described, but the present invention is not limited to this. For example, the timer count expiration value may be set to other than 0. Alternatively, the timer 5002-1 and the timer 5002-2 may be configured as count-up timers, and the count is initialized to 0 by resetting, and the expiration state is reached when the count reaches the preset timer count expiration value.

[0092] When the station device 4002 receives the wireless frame (first wireless frame) 7003 to which a response is required and no error is detected in the wireless frame 7003, it transmits an Ack frame 7004 as a response frame to the wireless frame 7003. At this time, the case where the timer 5002-2 is not in the expired state (is in the activated state) is the same as the case where the timer 5002-2 is not in the expired state (is in the activated state). Figure 7 Unlike the example of , the detection frame 7005 is not sent following the Ack frame 7004. At this time, the timer 5002-1 is not reset, and the timer 5002-1 and the timer 5002-2 continue to be activated.

[0093] When the active state continues, the timer 5002-2 reaches count 0 earlier than the timer 5002-1 and transits to the expired state (7203). At this time, the timer 5002-2 indicates that it is in the expired state (7051).

[0094] When the station device 4002 receives the wireless frame 7051 that requires a response and no error is detected in the wireless frame 7051, it transmits an Ack frame 7052 as a response frame to the wireless frame 7051. At this time, when the timer 5002-2 becomes expired (7203), the probe frame 7053 is transmitted after the Ack frame 7052, and the timer 5002-1 and the timer 5002-2 are reset to the timer count initial value (7054). The reset timer 5002-1 and the timer 5002-2 become activated (7103, 7204), and countdown starts from the timer count initial value. It should be noted that the timing of resetting the timer 5002-1 and the timer 5002-2 (7054) is not limited to the time when the probe frame 7053 is transmitted, and can be set within a range where the effect does not change, such as between the timing of transmitting the Ack frame 7052 and the timing of transmitting the probe frame 7053.

[0095] The wireless frame that needs a response is not limited to a data frame, and may be a frame including control information that needs a response. The sending of the Ack frame 7052 and the sending of the probe frame 7053 are preferably performed at an interval of SIFS, but are not limited thereto, and other IFSs used in the case of high priority may also be used. Moreover, the Ack frame and the probe frame may be connected and sent. In addition, a frame that combines the Ack frame and the probe frame may be redefined and sent.

[0096] The radio frame 7051 may be a data frame for transmitting an A-MPDU that aggregates multiple MPDUs, and the Ack frame may be a block Ack frame. When a block Ack frame is used, the transmission of the probe frame 7053 may be implemented to reset the timer 5002-1 and the timer 5002-2 only when the number or ratio of positive responses included in the block Ack is less than a specified value. In this case, when the timer 5002-1 is not in an expired state, the transmission of the probe frame can be suppressed when the state of the radio link is good, thereby reducing the overhead generated by the transmission of the probe frame.

[0097] When the timer 5002-2 shows a count of 0 and reaches an expiration state (7205)(7055) and the count of the timer 5002-1 reaches 0 and reaches an expiration state (7104), the station device 4002 enters a probe frame transmission standby state (7007). When the timer 5002-1 expires, the station device 4002 performs carrier sensing and confirms that the wireless channel is idle, and then starts a backoff process (7008). During the backoff period, when the wireless channel is idle, the station device 4002 transmits a probe frame 7009 and resets the timer 5002-1 and the timer 5002-2 (7010). The timer 5002-1 and the timer 5002-2 are reset to the timer count initial value and transition to the active state, and the countdown operation starts (7105, 7206).

[0098] and Figure 7 Different from the example of, the fourth control information included in the wireless frame 7011 sent by the access point device 4001 to the station device 4002 may include, in addition to the information such as the setting release related to the timer 5002-1, the information such as the setting release related to the timer 5002-2. It should be noted that the information on the setting release related to the timer 5002-2 may be information that is common to the information on the setting release of the timer 5002-1. When the station device 4002 receives the wireless frame 7011 including the fourth control information, it deactivates the timer 5002-1 and the timer 5002-2 (7012). The deactivated timer 5002-1 and the timer 5002-2 stop the countdown action and migrate to the deactivated state 7106 and 7207.

[0099] In addition, as a modified example, when the first control information is not directly received from the access point device 4001 but other control information is received, information equivalent to the first control information may be generated in the station device 4002 based on the received control information. As an example, when receiving the setting information related to QoS, the station device 4002 may activate (7002) after setting the timer count initial value of the timer 5002-1 and the timer 5002-2. The station device 4002 may change the count initial value of each timer according to the condition requested as QoS. When the allowable delay time is set to be short, the count initial value of each timer may be reduced. In addition, when the bit rate guarantee is set, the count initial value of each timer may be reduced. In addition, the station device 4002 may set the timer count initial value of the timer 5002-1 and the timer 5002-2 based on the capability information exchanged with the access point device 4001. The setting of QoS may be set by the access point device 4001 according to the current traffic status, or may be set according to the application executed on the network. In addition, an application executed on the network can obtain QoS settings via the access point device 4002.

[0100] In addition, as a modified example, when the fourth control information is not directly received from the access point device 4001 but other control information is received, information equivalent to the fourth control information may be generated in the station device 4002 based on the received control information. As an example, when the setting information related to QoS is received, the station device 4002 may deactivate the timer 5002-1 and the timer 5002-2 (7012). When the allowed delay time is set to be long, the timer 5002-1 and the timer 5002-2 may be deactivated. In addition, when the setting of the bit rate is set to the best effort service, the timer 5002-1 and the timer 5002-2 may be deactivated.

[0101] Fig. 9 2 is a flowchart showing an example of a detection process of the station device 4002 when the timer 5002-1 and the timer 5002-2 are used.

[0102] When the station device 4002 sends an Ack frame (Yes in step S9001), it checks whether the timer 5002-2 has expired (step S9002). When the timer 5002-2 has expired (Yes in step S9002), it sends a probe frame after sending the Ack frame (step S9003), resets the timer 5002-1 and the timer 5002-2 (step S9004), and returns to step S9001.

[0103] If the answer is no in step S9001, check whether timer 5002-1 has expired (step S9005). If timer 5002-1 has not expired (step S9005 is no), return to step S9001. If timer 5002-1 has expired (step S9005 is yes), perform carrier sensing (step S9006), after performing the backoff process (step S9007), send a detection frame (step S9008), reset timer 5002-1 and timer 5002-2 (step S9009), and return to step S9001. It should be noted that, although not shown in the figure, if the wireless channel is busy during the period of carrier sensing and backoff process, retry is performed from step S9006, and if the wireless frame to be received is detected, return to step S9001.

[0104] Next, as a modified example, an example corresponding to multi-link operation (MLO) is described in which the access point device 4001 and the station device 4002 simultaneously use two wireless links, namely, a first wireless link and a second wireless link using a frequency band (or frequency channel) different from the first wireless link, to communicate. It should be noted that MLO is not limited to two wireless links, and multiple wireless links in different frequency bands (or frequency channels) may also be used.

[0105] A multi-link device (MLD) is a device that can perform multi-link communication through multi-link operation. The access point device corresponding to MLO is called an MLD access point device, and the station device corresponding to MLO is called an MLD station device. In addition, the MLD access point device and the MLD station device are collectively referred to as an MLD wireless communication device. In this embodiment, the wireless communication devices 4001-1, 4001-2, 4002A, and 4002B are described as MLD wireless communication devices, but in actual use, all wireless communication devices in the wireless communication system may not necessarily correspond to MLO.

[0106] use Fig.10 The MLD access point device 10001 and the MLD station device 10002 are described below. The MLD wireless communication device is composed of a plurality of sub-wireless communication devices corresponding to the frequency bands (or frequency channels) of each wireless link (also called a physical layer link) constituting the multi-link. Each sub-wireless communication device may correspond to all the frequency bands (and frequency channels) corresponding to the MLD wireless communication device, or may correspond to any one of the frequency bands (or frequency channels). Fig.101 shows an example in which the MLD access point device 10001 is composed of two sub-wireless communication devices, in this case, two sub-access point devices 10001-1 and 10001-2 and a multi-link control unit 10011, but the number of sub-access point devices can be any number greater than two. It should be noted that, in the following, when any one of the multiple sub-access point devices is used as a representative for description, it is referred to as the sub-access point device 10001-N. Fig.10 10002 is also shown as an example in which the MLD station device 10002 is composed of two sub-wireless communication devices, in this case, two sub-station devices 10002-1 and 10002-2 and a multi-link control unit 10012, but the number of sub-station devices is any number greater than two. It should be noted that, hereinafter, when describing any one of the multiple sub-station devices as a representative, it is referred to as the sub-station device 10002-N. In addition, the sub-wireless communication device (sub-access point device and sub-station device) 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, sub-station unit).

[0107] exist Fig.10 In the embodiment, an example is shown in which a plurality of sub-wireless communication devices are logically configured as independent blocks, but they may also be physically configured by one wireless communication device. Alternatively, a plurality of sub-wireless communication devices may be physically configured as independent devices. In this embodiment, the case in which each sub-wireless communication device is physically configured as an independent device is described as an example.

[0108] 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, capability, etc. of each MLD wireless communication device. For an MLD wireless communication device with a higher level, higher category, and higher capability, 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 existing in a wireless communication system, the sub-wireless communication devices (sub-access point devices, sub-station devices) constituting each MLD wireless communication device may be different according to the level, category, capability, etc., or their numbers may not be the same.

[0109] The slave station device 10002-1 is connected (Association) with the slave access point device 10001-1, and a wireless link 10003-1 (first wireless link) is established. The slave station device 10002-2 is connected with the slave access point device 10001-2, and a wireless link 10003-2 (second wireless link) is established.

[0110] Fig.10 The structure and Figure 6 The structure of the access point device 4001 in FIG. 1 is the same as that of the access point device 4001 in FIG. 1 , except that the multi-link control unit 10011 is connected to the wireless control unit 6001 of each sub-access point device 10001-N. The multi-link control unit 10011 controls the wireless link of each sub-access point device 10001-N, and exchanges control information and transmission and reception data with each sub-access point device 10001-N. The multi-link control unit 10011 allocates data frames to the sub-access point devices 10001-1 and 10001-2, that is, the wireless links 10003-1 and 10003-2, and aggregates the wireless links 10003-1 and 10003-2 from the sub-access point devices 10001-1 and 10001-2 that receive data frames.

[0111] on the other hand, Fig.10 The structure of the slave station device 10002-N in Figure 5 The structure of the station device 4002 in the embodiment is the same as that of the station device 4002 in the embodiment, except that the multi-link control unit 10012 is connected to the wireless control unit 5001 of each substation device 10002-N. The multi-link control unit 10012 controls the wireless link of each substation device 10002-N, and exchanges control information and received and sent data with each substation device 10002-N. The multi-link control unit 10012 allocates data frames to each substation device 10002-1 and 10002-2, that is, each wireless link 10003-1 and 10003-2, and aggregates data frames from each substation device 10002-1 and 10002-2, that is, each wireless link 10003-1 and 10003-2.

[0112] In the following description, for simplicity of description, as an example, the case where the wireless links constituting the multi-link are the wireless link 10003-1 (first wireless link) and the wireless link 10003-2 (second wireless link) is described, but it is not limited to this, and the same can be applied when the number of wireless links is three or more. In addition, the case where the frequency band of the first wireless link is the 2.4 GHz band and the frequency band of the second wireless link is the 5 GHz band is described as an example, but the frequency band used by each wireless link can be arbitrarily set from the frequency bands (or frequency channels) supported by the wireless communication system such as the 2.4 GHz band, the 5 GHz band, the 6 GHz band, and the 60 GHz band, which will also change according to the laws and regulations of each country.

[0113] An example of the detection process in this variant is described. Figure 7 The operation is the same as that in the case where the wireless link is one. That is, in the first wireless link, the slave access point device 10001-1 performs communication with Figure 7The access point device 4001 performs the same operation as the slave station device 10002-1. Figure 7 In the second wireless link, the slave access point device 10001-2 performs the same operation as the station device 4002. Figure 7 The access point device 4001 performs the same operation as the slave station device 10002-2. Figure 7 The same operation as the station device 4002. Figure 7 Similarly, the timer included in the timer unit 5002 of the slave device 10002-1 is referred to as timer 5002-1 (first timer), and the timer included in the timer unit 5002 of the slave device 10002-2 is referred to as timer 5002-3 (second timer). Figure 7 The description will focus on the differences in an example of the detection process, and the description of the same parts will be omitted.

[0114] The first radio link operation and Figure 7 In the second wireless link, the slave station device 10002-2 receives the wireless frame 7001-2 (replacing the wireless frame 7001-2) including the setting information related to the timer 5002-3 and the second control information including the detection frame transmission condition from the slave station device 10002-2 from the slave access point device 10001-2. Figure 7 7001. The same below), after setting the timer count initial value of timer 5002-3, activation (7002-2) is performed. It should be noted that the setting information related to timer 5002-3 may include the timer count initial value, the timer count expiration value, the timer activation indication information, the timer reset indication information, the timer reset timing information, etc. By activating 7002-2, timer 5002-3 is reset to the timer count initial value, migrates from the deactivated state 7101-2 to the activated state 7102-2, and starts the countdown action. Timer 5002-3 continues to count down while it is in the activated state. It should be noted that the example of simultaneously performing the setting, resetting, activating, and starting the countdown of the timer count initial value of timer 5002-3 through the reception of the wireless frame 7001 is described, but it is not limited to this. For example, other wireless frames (the control information included therein) can also be triggered to perform the setting and resetting of the timer count initial value, activation, and countdown start.

[0115] In addition, the timer 5002-3 is assumed to be a countdown timer, and the count becomes a preset timer initial value by being reset, and the example of the expiration state of the count of 0 is described, but it is not limited to this. For example, the timer count expiration value may be set to other than 0. Alternatively, the timer 5002-3 may be configured as an up-counting timer, and is initialized to count 0 by being reset, and the expiration state is reached when the count reaches the preset timer count expiration value.

[0116] When the substation device 10002-2 receives the wireless frame (second wireless frame) 7003-2 that requires a response and no error is detected in the wireless frame 7003-2, it sends an Ack frame 7004-2 as a response frame to the wireless frame 7003-2, then sends a detection frame 7005-2 (hereinafter, the detection frame sent in the second wireless link will also be referred to as the second detection frame), and resets the timer 5002-3 to the timer count initial value (7006-2). The reset timer 5002-3 continues to be activated (7103-2) and counts down from the timer count initial value. It should be noted that the timing of resetting (7006-2) the timer 5002-3 is not limited to the time when the detection frame 7005-2 is sent, and can be set within a range where the effect remains unchanged, such as between the timing of sending the Ack frame 7004-2 and the timing of sending the detection frame 7005-2.

[0117] The wireless frame that needs a response is not limited to a data frame, and may be a frame including control information that needs a response. The sending of the Ack frame 7004-2 and the sending of the probe frame 7005-2 are preferably performed at an interval of SIFS, but are not limited thereto, and other IFSs used in the case of high priority may also be used. Moreover, the Ack frame and the probe frame may be connected and sent. In addition, a frame that combines the Ack frame and the probe frame may be redefined and sent.

[0118] When wireless frame 7003-2 is received, detection frame 7005-2 can be sent to reset timer 5002-3 only when the count of timer 5002-3 reaches a specified value (below the specified value). In this case, when timer 5002-3 does not reach the specified value, that is, the time elapsed from the last detection frame transmission is less than the specified time, the transmission of the detection frame can be suppressed, reducing the overhead generated by the detection frame transmission.

[0119] The wireless frame 7003-2 may be a data frame for transmitting an A-MPDU that aggregates multiple MPDUs, and the Ack frame may be a block Ack frame. When a block Ack frame is used, the transmission of the probe frame 7005-2 may be implemented to reset the timer 5002-3 only when the number or ratio of positive responses included in the block Ack is less than a specified value. In this case, when the timer 5002-3 is not in an expired state, the transmission of the probe frame can be suppressed when the state of the wireless link is good, thereby reducing the overhead generated by the transmission of the probe frame.

[0120] When the count of timer 5002-3 is 0 and in the expired state (7104-2), substation device 10002-2 enters the standby state for sending the detection frame (7007-2). When timer 5002-3 expires, substation device 10002-2 performs carrier sensing and confirms that the wireless channel is idle, and then starts the backoff process (7008-2). During the backoff period, when the wireless channel is idle, substation device 10002-2 sends a detection frame 7009-2 and resets timer 5002-3 (7010-2). Timer 5002-3 is reset to the initial value of the timer count and migrates to the active state, and the countdown action begins (7105-2).

[0121] When the substation device 10002-2 receives the wireless frame 7011-2 including the control information (sixth control information) including the setting release information related to the timer 5002-3, the substation device 10002-2 deactivates the timer 5002-3 (7012-2). The deactivated timer 5002-3 stops the countdown action and moves to the deactivated state 7106. It should be noted that when the substation device 10002-1 receives the fourth control information in the first wireless link, the substation device 10002-2 can also deactivate the timer 5002-3. In addition, when the substation device 10002-2 receives the sixth control information in the second wireless link, the substation device 10002-1 can also deactivate the timer 5002-1.

[0122] In addition, as a modified example, when the second control information is not directly received from the sub-access point device 10001-2, but other control information (fifth control information) is received, information equivalent to the second control information can be generated in the sub-station device 10002-2 based on the received control information. As an example, when receiving the setting information related to QoS, the sub-station device 10002-2 can be activated (7002-2) after setting the timer count initial value of the timer 5002-3. The sub-station device 10002-2 can change the timer count initial value according to the condition requested as QoS. When the allowed delay time is set to be short, the timer count initial value can be reduced. In addition, when the bit rate guarantee is set, the timer count initial value can also be reduced. In addition, the sub-station device 10002-2 can set the timer count initial value of the timer 5002-3 based on the capability information exchanged with the sub-access point device 10001-2. The QoS setting can be set by the slave access point device 10001-2 according to the current traffic status, or according to the application executed on the network. In addition, the application executed on the network can obtain the QoS setting via the slave access point device 10001-2.

[0123] In addition, as a modified example, when the sixth control information is not directly received from the sub-access point device 10001-2 but other control information is received, information equivalent to the sixth control information may be generated in the substation device 10002-2 based on the received control information. As an example, when the setting information related to QoS is received, the substation device 10002-2 may deactivate the timer 5002-3 (7012-2). When the allowed delay time is set to be long, the timer 5002-3 may be deactivated. In addition, when the setting of the bit rate is set to best effort, the timer 5002-3 may be deactivated.

[0124] In addition, the substation device 10002-2 connected to the sub-access point device 10001-2 can have multiple timers for detection control. Similar to the first timer and the third timer, the substation device 10002-2 has a second timer and a fourth timer. When the fourth timer is not in the expired state when sending the response frame, it can be configured not to send the detection frame. In addition, the substation device 10002-2 can also be configured to perform carrier sensing when the second timer expires and after confirming that the wireless channel of the second link is idle, perform backoff processing and send the detection frame. The substation device 10002-2 can reset the second timer and the fourth timer after sending the detection frame. It can also be set so that the time until the fourth timer expires is shorter than the timer expiration time of the second timer.

[0125] When configured as MLD, when a station device receives control information for changing a setting such as a timer count initial value in any of the activated links, the station device can activate or deactivate the timer for the activated links other than the link for which the control information was received. In addition, when a station device receives setting information related to QoS in any of the activated links, the station device can activate or deactivate the timer for the activated links other than the link for which the QoS information was received.

[0126] According to the method described above, the communication quality of the wireless link in wireless communication can be well maintained. [2. Common points in all embodiments]

[0127] 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.

[0128] 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.

[0129] 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. In the case of integrating each functional block into an integrated circuit, an integrated circuit control unit for controlling them is attached. It should be noted that in order to implement at least part of the functions of the above-mentioned embodiment, the situation of downloading programs or setting information from a server computer is of course also included in the present invention.

[0130] 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.

[0131] 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.

[0132] 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

[0133] The present invention is applicable to a wireless communication device and a wireless communication method. Description of Reference Numerals 3001: NDP announcement frame 3002: NDP frame 3003: Compressed beamforming / CQI frame 4001-1, 4001-2: Wireless communication device (access point device) 4002-1~6: Wireless communication device (station device) 4003-1, 4003-2: Wireless communication systems 5001: Wireless control unit 5002: Timer unit 5003: Wireless Communications Department 5003a: Physical layer frame generation unit 5003b: Wireless transmission unit 5003c: Wireless receiving unit 5003d: Received power measurement unit 5003e: Channel estimation unit 5003f: Signal demodulation unit 5004: Antenna Department 6001: Wireless control unit 10001: MLD access point device 10001-1: Sub-access point device 10001-2: Sub-access point device 10002: MLD station device 10002-1: Substation device 10002-2: Substation device 10003-1: First wireless link 10003-2: Second wireless link 10011: Multi-link control unit 10012: Multi-link control unit

Claims

1. A wireless communication device for communicating with a wireless communication device of a communication partner using a wireless link, wherein the wireless communication device comprises: a wireless communication unit that transmits and receives wireless frames on a first wireless link; and The wireless control unit includes a first timer. When the wireless communication unit receives a wireless frame including first control information indicating setting of the first timer, the wireless control unit sets the first timer to an active state. When a first radio frame requiring a response is received in the first radio link, the wireless communication unit sends a first response frame to the first radio frame, and then sends a first detection frame without carrier sensing, and the wireless control unit resets the first timer. When the first timer expires, the wireless communication unit transmits the first probe frame after performing carrier sense in the first wireless link, and the wireless control unit resets the first timer.

2. The wireless communication device according to claim 1, wherein: The wireless communication device is a device that uses multiple wireless links to communicate with the wireless communication device of the communication partner at the same time, wherein the multiple wireless links include the first wireless link and a second wireless link with a frequency band different from that of the first wireless link, wherein: The wireless communication unit also sends and receives wireless frames on the second wireless link. The wireless control unit further includes a second timer. When the wireless communication unit receives a wireless frame including second control information indicating setting of the second timer, the wireless control unit sets the second timer to an active state, In the second radio link, when a second radio frame requiring a response is received, the wireless communication unit transmits a second response frame to the second radio frame, and then transmits a second probe frame without carrier sensing, and the wireless control unit resets the second timer. When the second timer expires, the wireless communication unit transmits the second probe frame after performing carrier sensing in the second wireless link, and the wireless control unit resets the second timer.

3. The wireless communication device according to claim 1, wherein: When the first timer reaches a specified value when the first radio frame is received, The wireless communication unit transmits the first probe frame without carrier sensing following transmission of the first response frame.

4. The wireless communication device according to claim 1, wherein: In the case where the first response frame is a block response frame, When the number of positive responses included in the block response frame is less than a predetermined number, the wireless communication unit transmits the first probe frame without carrier sensing following transmission of the block response frame.

5. The wireless communication device according to claim 1, wherein: When the wireless communication unit receives a wireless frame including third control information, the wireless control unit sets an expiration condition of the first timer and resets the first timer.

6. The wireless communication device according to claim 5, characterized in that: The third control information is information for setting quality of service QoS.

7. The wireless communication device according to claim 1, wherein: When the wireless communication unit receives a wireless frame including fourth control information, the wireless control unit sets the first timer to a deactivated state.

8. The wireless communication device according to claim 7, characterized in that: The fourth control information is information for releasing the setting of QoS.

9. The wireless communication device according to claim 1, wherein: The wireless control unit further includes a third timer, and when the wireless communication unit receives a wireless frame including the first control information, the wireless control unit sets the first timer and the third timer to an activated state. When the third timer expires when the first radio frame is received, the wireless communication unit transmits the first detection frame without carrier sensing following transmission of the first response frame, and the wireless control unit resets the first timer and the third timer. When the first timer expires, the wireless communication unit transmits the first probe frame after performing carrier sensing in the first wireless link, and the wireless control unit resets the first timer and the third timer.

10. The wireless communication device according to claim 2, wherein: When the first timer reaches a predetermined value when the first radio frame is received, the wireless communication unit transmits the first probe frame without carrier sensing, following transmission of the first response frame. When the second timer reaches a predetermined value when the second radio frame is received, the wireless communication unit transmits the second probe frame without carrier sensing, following transmission of the second response frame.

11. The wireless communication device according to claim 2, characterized in that: In the case where the first response frame or the second response frame is a block response frame, When the number of positive responses included in the block response frame is less than a predetermined number, the wireless communication unit transmits the first probe frame or the second probe frame without carrier sensing following transmission of the block response frame.

12. The wireless communication device according to claim 2, characterized in that: When the wireless communication unit receives a wireless frame including the third control information, the wireless control unit sets an expiration condition of the first timer and resets the first timer. When the wireless communication unit receives a wireless frame including fifth control information, the wireless control unit sets an expiration condition of the second timer and resets the second timer.

13. The wireless communication device according to claim 2, characterized in that: When the wireless communication unit receives a wireless frame including fourth control information, the wireless control unit sets the first timer to a deactivated state, When the wireless communication unit receives a wireless frame including sixth control information, the wireless control unit sets the second timer to a deactivated state.

14. A wireless communication device for communicating with a wireless communication device of a communication partner using a wireless link, wherein the wireless communication device comprises: a wireless communication unit that transmits and receives wireless frames on a first wireless link; and The wireless control unit generates control information. The wireless control unit generates first control information including setting and resetting conditions related to a first timer of the wireless communication device of the communication partner and a transmission condition of a probe frame from the wireless communication device of the communication partner, The first wireless communication unit transmits a wireless frame including the first control information.

15. A wireless communication method, which is a communication method in a wireless communication device that uses a wireless link to communicate with other wireless communication devices, wherein the wireless communication method is characterized by comprising the following steps: receiving a wireless frame including first control information indicating setting a first timer; When receiving a radio frame including the first control information, setting the first timer to an activated state; In a first wireless link, receiving a first wireless frame requiring a response; Sending a first response frame to the first wireless frame; Subsequent to sending the first response frame, sending a first detection frame without carrier sensing, and resetting the first timer; as well as When the first timer expires, the first detection frame is sent after carrier sensing in the first radio link, and the first timer is reset.

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