TWI741083B - Wireless communication method and wireless communication device - Google Patents

Abstract

The wireless communication device of the present invention transmits a beacon frame in a BTI (Beacon transmission interval), and during a BFT (Beamforming Training) after BTI, it receives and transmits SSW ( Sector Sweep (Sector Sweep) frame, when the transmission SSW frame contains the requested information, from the transmission SSW frame, the information of the first transmission sector selected by other wireless communication devices is retrieved, and the information contained in The transmission sector used by other wireless communication devices that transmit SSW frames. Select the second transmission sector. During BFT, use the first transmission sector to send a feedback containing information about the selected second transmission sector. In the frame, during the data transmission period after the BFT period, the first transmission sector is used to transmit a detection response frame containing information about the selected second transmission sector.

Description

Wireless communication method and wireless communication device

FIELD OF THE INVENTION The present disclosure relates to a wireless communication method and wireless communication device.

BACKGROUND OF THE INVENTION IEEE 802.11 is one of wireless LAN-related standards, and includes, for example, the IEEE 802.11ad standard (hereinafter referred to as the "11ad standard") (for example, refer to Non-Patent Document 1).

In the 11ad specification, beamforming (BF) technology is used. Beamforming is to change the directivity of one or more antennas of the transmitting part and the receiving part of the wireless communication device respectively, and to set the directivity of the antennas to communicate to optimize the communication quality, such as the receiving strength. Way. Advanced technical literature

Non-Patent Literature Non-Patent Literature 1: IEEE 802.11ad ^TM -2012, pages 278-314 and pages 337-339, issued on December 28, 2012

SUMMARY OF THE INVENTION When the beamforming is not completed during active scanning, the conventional STA (Station) will try beamforming again during, for example, DTI (Data Transmission Interval). At this time, there is a time delay until the STA completes the discovery of AP/PCP (Access Point/Personal basic service set Control Point). In addition, it causes interference to other STAs performing data communication.

An aspect of the present disclosure provides a wireless communication method and wireless communication device, which reduces the time delay until the discovery is completed.

One aspect of the wireless communication method of the present disclosure is a wireless communication method of a wireless communication device, which includes: transmitting more than one beacon frame during the beacon transmission period; during the beamforming training period after the beacon transmission period, Receive more than one transmission sector scan frame from other wireless communication devices; when the aforementioned one or more transmission sector scan frames contain information about the discovery request, scan the frame from the aforementioned one or more transmission sectors, Retrieve information about the first transmission sector selected by the aforementioned other wireless communication device; scan the frame from more than one transmission sector included in the aforementioned received, and be the transmission fan used by the aforementioned other wireless communication device Zone, select the second transmission sector; during the beamforming training period, use the first transmission sector to transmit a feedback frame containing information about the selected second transmission sector; and during the beamforming training During the data transmission period after the period, the first transmission sector is used to transmit a detection response frame containing information about the selected second transmission sector.

Furthermore, these aspects of coverage and specificity are realized by systems, devices, methods, integrated circuits, computer programs or recording media, or by systems, devices, methods, integrated circuits, computer programs, and records Any combination of media can be realized.

According to an aspect of the present disclosure, the delay to the completion of discovery can be reduced.

Further advantages and effects of one aspect of the present disclosure can be clarified from the description and drawings. The advantages and/or effects are respectively provided by the features described in the several embodiments and the specification and drawings, but it is not necessary to provide all of them in order to obtain one or more of the same features.

Modes for Carrying Out the Invention Hereinafter, with appropriate reference to the drawings, embodiments of the present invention will be described in detail. However, the detailed description above is sometimes omitted if necessary. For example, detailed descriptions of matters that are already widely known may be omitted, or repeated descriptions of substantially the same configuration may be omitted. This is to prevent the following explanation from becoming unnecessarily lengthy, so that people familiar with the art can easily understand it.

Furthermore, the drawings and the following description are provided to allow those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the scope of the patent application by these.

In order for an STA as an example of a wireless communication device to establish an initial connection with other STAs, a procedure for discovering other STAs is called Discovery. As applications that utilize 60GHz ultra-high frequency communication, for example, data downloads of automatic ticket machines that require high-speed connections, and backup wireless connections in data centers to replace and/or complement wired networks are conceivable. Since this type of application requires high-speed connection, review the discovery of high-speed, for example, below 100msec.

The 60GHz ultra-high frequency communication standard IEEE802.11ad stipulates active scanning as a discovery procedure. In active scanning, it includes BTI (Beacon Transmission Interval) processing, A-BFT (Association-Beam Forming Training) period processing and Probe exchange processing procedures.

FIG. 1 is an example of a block diagram when the STA 100 performs active scanning and discovers other STAs (PEER STA). Furthermore, other STAs (STA200) that perform active scanning sometimes coexist. PEER STA can also be an example of a wireless base station (wireless communication device) AP or PCP (expressed as "AP/PCP"). In addition, STA100 and STA200 may also be non-AP/PCP STAs (slave, terminal: wireless communication device). Furthermore, in order to simplify the description, the wireless communication device is described as a wireless base station and a slave (terminal), but the wireless base station can operate as a slave or the slave can also operate as a radio base station.

In BTI, STA100 receives the transmission sector scan using DMG (Directional Multi-Gigabit) beacon frames (hereinafter sometimes expressed as "DMG beacons").

Furthermore, AP/PCP300 switches transmission sectors (transmission beams) while transmitting multiple DMG beacons. The STA100 receives the DMG beacon and measures the reception strength and/or reception quality. Furthermore, the STA100 that performs active scanning sometimes performs transmission sector scanning in the BTI.

During the A-BFT period, the STA100 receives or transmits the transmission sector scan (of the STA100) using the SSW (Sector SWeep) frame. In addition, the STA 100 receives or transmits SSW feedback (SSW-FB) frames.

Furthermore, the STA 100 switches the transmission sector (transmission beam) for each SSW frame to transmit the SSW frame. The AP/PCP300 receives the SSW frame, measures the reception strength and/or reception quality, and sends the SSW-FB frame containing the measurement result to the STA100. STA100 receives the SSW-FB frame and completes the BFT. Furthermore, during the BTI, when the STA100 performs transmission scanning, during the A-BFT period, the AP/PCP300 performs transmission sector scanning, and the STA100 transmits the SSW-FB frame.

As the BFT, the STA100 that performs active scanning determines the best sector for transmission (appropriate beam for transmission) during the BTI and A-BFT periods. Furthermore, the beam represents the directivity of the antenna. When the BFT is completed, STA100 sends a Probe request frame (hereinafter sometimes only referred to as "Probe request") during the Probe exchange process. When AP/PCP300 receives a Probe request, it sends a Probe response frame (hereinafter sometimes only expressed as "Probe Response").

Furthermore, when BFT is not performed, STA100 performs omni-directional communication. However, due to the large propagation loss in 60GHz ultra-high frequency communication, it is sometimes difficult to make the omnidirectional transmission signal reach the AP/PCP300.

STA100 obtains information about the connected terminal (for example, AP/PCP300) and BSS (Basic Service Set) through Probe exchange processing. STA100 decides the connection object based on the obtained information. For example, STA100 decides whether to connect to AP/PCP300 or to discover other terminals.

Here, in the 11ad specification, the A-BFT period is shared with other STAs receiving DMG beacons.

FIG. 2 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning. In FIG. 2, BI (beacon interval) includes BTI, A-BFT period, and DTI (Data Transfer Interval). For example, STA100 and STA200 receive DMG beacons ("DBcn" in the figure) at BTI, and perform transmission sector scanning (SSW frame transmission) during A-BFT.

During the A-BFT period, because multiple STAs perform transmission sector scanning and compete with each other (for example, the collision of transmission packets), the number of STAs that receive the SSW-FB frame and complete the BFT is sometimes at most one. In Figure 2, the SSW-FB frame sent by AP/PCP300 targeting STA100 is received by STA100, and STA200 does not receive the SSW-FB frame.

In this way, the STA 100 performs Probe exchange processing (processing from the transmission of the Probe request to the reception of the Probe response) in the DTI. Furthermore, the AP/PCP300 sends an ACK frame when the received Probe request does not contain errors. For example, FCS (Frame Check Sequence) and/or CRC (Cyclic Redundancy Check) can be used to determine whether the Probe request contains errors. In addition, the description of ACK is omitted.

The STA (STA200) that has not completed the BFT can also wait for the next BTI (not shown) and try BFT again. However, in this case, since the processing delay is at least 1 beacon interval (for example, 100 msec), the delay is very large.

Furthermore, STA200 can also start sector scan in DTI. For example, a STA200 that has not completed beamforming (for example, failed due to competition) during the BTI and A-BFT periods can also perform BFT in the DTI after the A-BFT period.

However, there is interference on the wireless channel in DTI (due to sector scans performed by other STAs not shown, data transmission performed by STA100), and sometimes the probability of completing BFT is very low.

(Embodiment 1) In Embodiment 1, the active scanning STA sets the field (DR=1) indicating the discovery request in the SSW frame and sends it, and informs it to support the reception of the Probe response containing the beamforming feedback information.

As a result, during A-BFT and DTI, even when competing with other STAs that are actively scanning for sector scanning, the STA that transmits the SSW frame containing DR=1 can also determine beamforming by receiving the Probe response. The completion. Therefore, the probability of beamforming completion becomes higher, and the time taken for discovery is shortened.

Use Figure 3 to illustrate the STA100's active scanning procedure.

In the BTI of FIG. 3, the AP/PCP 300 changes the transmission sector for each DMG beacon (DBcn), and transmits the DMG beacon, for example.

In the BTI of FIG. 3, the STA 100 receives the DMG beacon. Furthermore, other STAs (STA200) can also receive DMG beacons in the same BTI.

During the A-BFT period in FIG. 3, the STA100 changes the transmission sector and transmits the SSW frame for each SSW frame that contains a field (DR=1) indicating the discovery request.

FIG. 4 is a diagram showing an example of the format of an SSW frame including a field (DR=1) indicating a discovery request. The SSW frame includes the Frame Control field, the Duration field, the RA (Receive(r) Address) field, and the TA (Transmit(ter) Address) field. Field, SSW (Sector Scan) field, SSW Feedback (SSW-FB) field, FCS (Frame Check Sequence) field.

The SSW field contains information about sector scanning. For example, STA100 changes the transmission sector for each SSW frame. When transmitting the SSW frame, the information related to the sector scan is the transmission sector ID.

The SSW-FB field includes the Sector Select sub-field, DMG Antenna Select sub-field, SNR Report (SNR: signal-to-noise ratio report) field, and Poll Required. Sub-field, Discovery Request (discovery request, recorded as DR) sub-field, Reserved (reservation) sub-field.

When the 11ad specification SSW frame (not shown) is transmitted during the A-BFT period, compared to the 7-bit Reserved sub-field in the SSW-FB field, the SSW frame in Figure 4 is in the SSW field. -FB field, including 6-bit reservation sub-field and 1-bit Discovery Request sub-field.

The sector selection subfield contains the sector ID (first transmission sector) included in the DMG beacon judged to be the best quality among the DMG beacons received by the STA 100 in the BTI. AP/PCP300 can also determine the sector ID of the best sector by receiving the SSW frame and obtaining the value of the sector selection sub-field.

The discovery request sub-field is used to respond to the AP/PCP300 requesting Probe containing beamforming feedback information. In short, the discovery request sub-field is used to notify AP/PCP300 that it supports the reception of a Probe response frame containing beamforming feedback information.

During the A-BFT period in FIG. 3, the AP/PCP300 receives one or more SSW frames.

The AP/PCP300 determines the transmission sector ID in the SSW frame with good reception quality in the received SSW frame as the best sector (second transmission sector) of the transmission target STA. In Figure 4, the transmission sector ID is included in the sector selection subfield of the SSW feedback field.

AP/PCP300 makes the SSW-FB frame contain the best sector information and sends it to STA100. STA100 receives the SSW-FB frame.

Furthermore, the STA100 may fail to detect the preamble due to FCS errors caused by, for example, noise, and/or competing with other STAs not shown in the transmission, and the reception of the SSW-FB frame may sometimes Failure (called a reception error).

Furthermore, even when the STA100 receives an SSW-FB frame, it may not send an ACK frame. Therefore, for AP/PCP300, it is unclear whether the SSW-FB frame during A-BFT is received by STA100. When AP/PCP300 receives an SSW frame containing DR=1 in A-BFT, it sends a Probe response containing beamforming feedback to STA100 at DTI.

FIG. 5 is a diagram showing an example of the format of the Probe response transmitted by the AP/PCP in the DTI.

The format of the Probe response in Figure 5 is the same as that of 11ad except for the frame body.

Probe response includes Frame Body (Probe Response frame body). The frame body of the Probe response in FIG. 5 is different from the frame body of the Probe response of the 11ad specification, and includes Beamforming Feedback (beamforming) elements.

The Beamforming Feedback component includes the Element ID field, Length field, Element ID Extension field, and SSW Feedback (SSW-FB) field.

The element ID field can also be used to distinguish the types of elements contained in the Probe Response frame body (such as Timestamp, SSID, Beamforming Feedback, and Vendor Specific elements). The value of the element ID field is specified in the 11ad standard for each type of element. The element ID that is not used in the 11ad specification, such as "222", can also be assigned to the element ID that identifies the Beamforming Feedback element.

The Length field is the number of octets to indicate the length of the remaining part of the Beamforming Feedback. For example, the octet number (3 or 4) of the element ID extension field (0 or 1 octet) and the SSW Feedback field (3 octets) combined is set as the value of the Length field.

The element ID extension field can also be used instead of the element ID field to identify the type of the element. For the element ID that identifies the Beamforming Feedback element, when assigning the element ID that is not used in the 11ad specification, the element ID extension field is not used, and the length is 0 octets.

The SSW Feedback field is the same as the SSW-FB field of the 11ad specification. In short, it is the same as setting the Discovery Request field to Reserved in the SSW Feedback field in Figure 4.

The AP/PCP300 sends the SSW-FB field of the Probe response in Figure 5 including the best sector of the STA100. Therefore, the STA100 can still obtain the best sector information even in the event of a receiving error of the SSW-FB frame. Furthermore, in the Probe Response frame body, it contains information about AP/PCP (including, for example, Capability Information: supported modulation methods and transmission rate information) and BSS information (for example, available wireless bandwidth ). Therefore, STA100 can still complete active scanning even when receiving errors of SSW-FB frames occur during the A-BFT period.

In addition, the STA 100 can also omit the transmission requested by the Probe (refer to FIG. 3) to reduce the delay.

In the DTI of Fig. 3, STA100 receives the Probe response that includes beamforming feedback (Beamforming Feedback element), and decides to use it according to the information included in the beamforming feedback (for example, the value of the Sector Select field). The best sector for communication with AP/PCP300. In addition, since the Probe response from the AP/PCP300 is received, the discovery of the AP/PCP300 based on the active scanning procedure is completed (successful).

After the STA100 actively scans (and can also perform additional discovery for other APs/PCPs), if the discovered AP/PCP is determined as the connection target, the following can also be performed. That is, the STA100 can also set the transmitting antenna to the best sector determined in the discovery, and transmit the connection request frame to the AP/PCP.

Furthermore, even if the AP/PCP300 has sent the SSW-FB frame to the STA100 during the A-BFT period, it can still send a Probe response including beamforming feedback in DTI. Even if a reception error occurs during the reception of the SSW-FB frame, the STA100 can still receive a Probe response including beamforming feedback in DTI.

In this way, for example, the STA100 can avoid retrying beamforming in DTI (transmission of SSW). Therefore, the delay required for discovery can be shortened.

In addition, the STA 100 can receive a Probe response without sending a Probe request in DTI. Therefore, the delay required for discovery can be shortened.

FIG. 6 is a diagram showing an example of a procedure for the STA 200 to perform active scanning in the same BI (beacon interval) that the STA 100 performs active scanning. In addition, description of the same processing of STA100 and AP/PCP300 as in FIG. 3 will be omitted. In addition, the description of the case where the STA200 performs the same processing as the STA100 in FIG. 3 is also omitted.

<Processing in BTI> STA200 receives the DMG beacon in BTI. Furthermore, when the locations and/or antenna directions of STA100 and STA200 are different, the best sector of STA100 is different from the best sector of STA200. Therefore, the reception quality of each DMG beacon received by STA100 is different from the reception quality of each DMG beacon received by STA200.

<Processing in A-BFT> During A-BFT, STA200 transmits SSW frame including DR=1 (same as STA100 in FIG. 3).

AP/PCP300 receives the SSW frame containing DR=1 during A-BFT. The SSW frame transmitted by the STA100 and the SSW frame transmitted by the STA200 can also be synchronized in transmission timing. Because the location, antenna direction and/or antenna directivity of STA100 and STA200 are different, even if SSW frames are transmitted at the same time (such as the same transmission slot), some SSW frames transmitted by STA100 arrive at AP/PCP300 (receive), and STA200 transmits The SSW frame does not reach the AP/PCP300 (not received) (the first SSW frame in Figure 6).

In addition, there are cases where the SSW frames transmitted by STA100 and STA200 arrive at AP/PCP300 and interfere with each other (called conflict or competition), and AP/PCP300 does not receive any SSW frame (the second SSW in Figure 6). Frame).

Also, there are cases where the SSW frame sent by STA200 reaches AP/PCP300 (received), but the SSW frame sent by STA100 does not reach AP/PCP300 (not received) (the third SSW frame in FIG. 6).

AP/PCP300 will determine the transmission sector ID (included in the SSW field in Figure 4) in the SSW frame with good reception quality among more than one SSW frame received by A-BFT as the transmission source The best sector for STA100 and 200.

AP/PCP300 can also determine the best sector for each transmission source STA when more than one SSW frame received includes multiple transmission source STAs.

During A-BFT, AP/PCP300 transmits SSW-FB frames according to the received SSW frames. For example, the AP/PCP300 can also use the transmission source (transmission source STA) of the received SSW frame as the transmission object of the SSW-FB frame. In addition, AP/PCP300 can also include the sector ID of the best sector of the transmission source STA determined during the A-BFT period in the SSW-FB frame.

The AP/PCP300 can also select a certain transmission source STA and transmit the SSW-FB frame when the multiple SSW frames received during the A-BFT period include multiple transmission source STAs.

AP/PCP300 can also select 1 STA of the transmission source of the SSW frame with the best reception quality (without regard to the transmission source STA) to transmit the SSW-FB frame. Even when competing with each other in A-BFT, STA can still receive SSW-FB frame, know the best sector, and exchange Probe.

AP/PCP300 can also select the source STA to send SSW-FB frame without DR=1. Since STAs that include DR=1 can receive Probe responses later, STAs that do not include DR=1 are given priority. In this way, the STAs of both parties can exchange Probes (receiving Probe responses) with a short delay.

During the A-BFT period in FIG. 6, the AP/PCP300 transmits the SSW-FB frame to the STA100, but does not transmit the SSW-FB frame to the STA200.

<Processing in DTI> When AP/PCP300 is in DTI, the SSW-FB field of the Probe response in Figure 5 contains the best sector of STA200, and the Probe response is sent. In this way, even if the STA200 does not receive the SSW-FB frame during the A-BFT period, it can still obtain the best sector information.

Furthermore, since the Probe Response frame body contains information about AP/PCP300 (including information such as Capability Information: supported modulation methods and transmission rate) and BSS information (such as available wireless bandwidth), STA200 even If the SSW-FB frame is not received during the A-BFT period, the active scan can still be completed.

In addition, the STA 200 can also omit the transmission requested by the Probe in DTI (refer to FIG. 2) to reduce the delay.

The AP/PCP300 can also obtain the TXOP (Tx Opportunity: Transmission Opportunity) used to transmit multiple frames for the transmission of Probe responses targeting STA100 and STA200 in DTI. Compared with the case where each STA obtains the TXOP required to transmit the Probe as shown in FIG. 2, since the TXOP can be secured at one time, the transmission can be made efficient.

STA100, 200 receive Probe response from AP/PCP300, and complete the discovery of AP/PCP300 based on active scanning procedure (success).

FIG. 7 is a flowchart showing an example of a procedure for STA100 to discover AP/PCP300.

First, STA100 starts to discover (S001).

Next, the STA 100 receives the DMG beacon in the BTI (S002). DMG beacons can also be sent for AP/PCP300 to perform sector scanning. In short, AP/PCP300 can also switch the transmission direction of the wireless signal by switching the transmission sector, and transmit more than 1 DMG beacon. AP/PCP300 can also send information elements and fields that indicate that A-BFT is scheduled after BTI, included in the DMG beacon.

Then, when the A-BFT period is not scheduled (S003: NO), the STA100 returns to S002 in order to wait for the next BTI.

When the A-BFT period is scheduled (S003: YES), the STA100 transmits the SSW frame containing DR=1 with AP/PCP300 as the transmission target during the A-BFT period (S004). Furthermore, STA100 can also send SSW frames for sector scanning. In short, the STA100 can also switch the transmission direction of the wireless signal by switching the transmission sector, and transmit more than 1 SSW frame. This is called response BFT, which is equivalent to responding to AP/PCP300's sector scan using DMG beacons, and STA100 performs sector scan. Furthermore, STA100 can also determine the best sector of AP/PCP300 according to the reception quality of the DMG beacon received at BTI. During A-BFT, the best sector information (such as sector ID) is included in the SSW frame and send.

When AP/PCP300 does not receive the SSW frame of S004 during A-BFT (S005: NO), it does not send the SSW-FB frame (and the Probe response of S012) to STA100, and the process returns to S002. Furthermore, the case where the SSW frame is not received may also include a case where a reception error occurs and/or a case where the received power is lower than a predetermined threshold.

When AP/PCP300 receives the SSW frame of S004 during A-BFT (S005: YES), it determines the best sector of STA100, prepares to communicate with STA100, and stores the best sector information in the memory (S006 ).

Then, AP/PCP300 sends the SSW-FB frame to STA100 (S007). AP/PCP300 can also send SSW-FB frames to other STA200. Or, AP/PCP300 may not send SSW-FB frame to any STA, but send Probe response in DTI (refer to S012). Or, AP/PCP300 can also use the best sector notified by the SSW frame during A-BFT to transmit the SSW-FB frame. Or, AP/PCP300 can also send the best sector information of STA100 included in the SSW-FB frame.

In addition, if the STA100 has not received the SSW-FB frame corresponding to S007 of the SSW frame transmitted in S004 (S008: NO), the flow proceeds to S012. Then, STA100 waits for the reception of Probe response.

If STA100 receives the SSW-FB frame corresponding to S007 of the SSW frame sent by S004 (S008: YES), it is ready to communicate with AP/PCP300, which will be included in the best sector of the SSW-FB frame The information is stored in the memory (S009).

Then, the STA100 judges that the initial BFT (success) between the AP/PCP300 and its own STA100 is completed (S010). In short, STA100 can use the best sector to communicate with AP/PCP300. Furthermore, the discovery is still in progress.

Then, the STA100 can also send a Probe request to the AP/PCP300 in the DTI (not shown in FIG. 7). Furthermore, the STA100 may also transmit an SSW frame containing DR=1 in step S004, and after completing the initial BFT, without transmitting the Probe request, it will shift to S012 to wait for the reception of the Probe response.

In addition, when the AP/PCP300 receives the Probe request and there is no receiving error, it sends an ACK frame to STA100 after SIFS (Short InterFrame Space) (for example, 3msec) (S011).

Next, the AP/PCP300 sends a Probe response in DTI (S012). AP/PCP300 can also enable Probe to send in response to information including the best sector of STA100.

STA100 receives the Probe response of S012 in DTI. When the received Probe response contains the information of the best sector of STA100, STA100 prepares to communicate with AP/PCP300, and stores the information of the best sector in the memory (S013).

Then, when the Probe responds with the information including the best sector of the STA100, the STA100 judges that the initial BF is completed (success) (S014). In short, STA100 can use the best sector to communicate with AP/PCP300.

Then, the STA100 stores the information (scanning result) of the AP/PCP300 included in the Probe response and the BSS managed by the AP/PCP300 in the memory (S015). Furthermore, the MAC processor of the STA100 can also notify the main controller of the scan result.

Then, STA100 completes the discovery of AP/PCP300 (S016). In order to discover other APs/PCPs (not shown), the STA100 can also be on the same wireless channel, or after switching the wireless channel, the process returns to S001 and repeats the discovery of other APs/PCPs.

FIG. 8 is a detailed block diagram showing an example of the structure of an STA (communication device) 100.

The antenna array transmits/receives wireless signals.

The receiving RF (Radio Frequency (Radio Frequency)) circuit converts the wireless signal received by the antenna array into a receiving analog base frequency signal. In addition, the receiving RF circuit changes the receiving gain and phase of the signal input from the antenna array according to the receiving sector ID specified by the PHY receiving circuit (it can also be the same sector as the best transmission sector), and controls the receiving antenna The directivity. In addition, the receiving RF circuit scans the frame for each transmission sector received to measure the reception quality.

The A/D (Analog-to-Digital Converter) circuit converts the received received analog base frequency signal into a received digital base frequency signal.

The PHY (Physical Layer: physical layer) receiving circuit performs synchronization, equalization, demodulation and/or decoding processing for receiving analog baseband signals, and generates received frame data.

The MAC (Media Access Control) processor recognizes and processes the MAC frame from the received frame data.

Identifying the MAC frame is to identify the type of the MAC frame (for example, MAC data frame, DMG beacon, Probe response). In addition, the processing of the MAC frame includes, for example, confirming FCS (Frame Check Sequence, a type of error detection code) to detect errors, and obtaining the information of each field according to the format of the recognized MAC frame. material.

In addition, the MAC processor fetches user data from the MAC data frame and outputs it to the main controller. In addition, the MAC processor generates a MAC data frame from user data input to the autonomous controller.

In addition, when the MAC processor receives the DMG beacon, it generates an SSW frame containing DR=1 (refer to S004 in FIG. 7). In addition, the MAC processor can also generate a Probe response when receiving an SSW frame containing DR=1 (refer to S012 in FIG. 7, AP/PCP300 processing). In addition, the MAC processor can also make a discovery request for the main controller.

The frame generated by the MAC processor is called transmission frame data (including, for example, the above-mentioned MAC data frame, SSW frame, and Probe response).

The PHY transmission circuit performs encoding, modulation, PHY frame formation and filtering for the transmission frame data to generate a transmission digital baseband signal.

The D/A (digital analog converter) circuit converts the transmitted digital base frequency signal into a transmitted analog base frequency signal.

The transmitting RF circuit converts the transmitting analog base frequency signal into a transmitting wireless signal. In addition, the transmission RF circuit changes the transmission gain and phase of the signal output to the antenna array 1001 in response to the transmission sector ID (the best transmission sector) specified by the PHY transmission circuit, and controls the directivity of the transmission antenna.

The main controller controls the MAC processor to perform the generation of transmitting user data and/or the processing of receiving user data. In addition, the main controller can also generate a Probe request in response to the discovery request from the MAC processor and input it to the MAC processor.

Fig. 9 is a detailed block diagram showing an example of the configuration of the MAC processor.

The message generating circuit generates and transmits MAC frames, such as DMG beacons and SSW frames.

The message generating circuit recognizes and processes the received MAC frame.

BFT control circuit In BFT processing, it controls the message generation circuit, message processing circuit, PHY transmission circuit, and PHY reception circuit, and controls the transmission/reception of DMG beacons and SSW frames. The BFT processing refers to, for example, the sector scan in the BTI of S002 in FIG. 7 and the sector scan in the A-BFT period of S004. In addition, the BFT control circuit outputs the control signal for selecting the best sector for transmission of AP/PCP or STA to the PHY transmission circuit based on the reception quality measured by the receiving RF circuit.

As above, STA100 makes the SSW frame include a field (DR=1) indicating the discovery request and sends it during A-BFT, requesting AP/PCP300 to send a Probe response containing beamforming feedback information. In this way, even when the AP/PCP300 does not transmit the SSW-FB frame, or when the STA100 does not receive or has difficulty receiving the SSW-FB frame, the STA100 can still receive the Probe response from the AP/PCP300 and complete the discovery.

Even when the AP/PCP300 does not transmit the SSW-FB frame, or the STA100 does not receive or has difficulty receiving the SSW-FB frame, it can still avoid waiting for the transmission of the SSW frame until the next BTI or A-BFT period, or The beamforming in DTI can be omitted. Therefore, the delay required for discovery can be shortened.

STA100 can complete BFT even when AP/PCP300 does not transmit SSW-FB frame, and/or STA100 does not receive or has difficulty receiving SSW-FB frame. Therefore, the best sector can be used to improve the communication quality with AP/PCP300. In addition, the beamforming retry can be reduced, which can reduce the interference to AP/PCP300 and/or other STAs.

(Modification of Embodiment 1) <Modification 1-1> AP/PCP300 can also receive an SSW frame containing a field (DR=1) indicating a discovery request. In DTI, the field indicating a support response is included in DMG beacon.

FIG. 10 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300. The AP/PCP300 receives the SSW frame containing the field (DR=1) indicating the discovery request, and transmits the field indicating the support response to the DMG beacon in the DTI.

Fig. 11 is a diagram showing an example of the format of a DMG beacon. In addition, since the DMG beacon and DMG Beacon frame body are the same as the 11ad specifications, detailed descriptions are omitted.

Compared to the 11ad standard DMG beacon (not shown), it contains a 6-bit Reserved subfield in the SSW field. The DMG beacon in Figure 11 contains a 5-bit reserved subfield in the SSW field. Field and the 1-bit Discovery Request Supported (DRS: discovery request support is possible) sub-field.

STA100 can also transmit an SSW frame containing DR=1 during the A-BFT period when receiving a DMG beacon with the DRS subfield set to 1 (DRS=1) in FIG. 11. Since DRS=1 is set, the STA100 can determine that the AP/PCP300 has the function of transmitting the Probe response shown in FIG. 4.

The STA100 can also transmit an SSW frame set to DR=0 during the A-BFT period when receiving a DMG beacon whose DRS subfield is not set to 1 (DRS=0) in FIG. 11.

When the DMG beacon does not include the Discovery Request Supported sub-field, it is difficult for the STA to distinguish whether the AP/PCP supports DR=1.

Therefore, when the STA transmits an SSW frame containing DR=1 during the A-BFT period, the AP/PCP300 sometimes does not transmit a Probe response containing beamforming feedback information in the DTI.

Therefore, it is difficult for the STA to determine whether to wait to receive the Probe response in the DTI or to perform the sector scan in the DTI. At this time, for example, the STA may also wait for a probe response for a certain period of time in the DTI, and perform a sector scan after the certain period of time has elapsed. However, in this case, the delay increases due to waiting for a certain period of time.

The DMG beacon contains the Discovery Request Supported sub-field. When DRS=1, the STA can also send an SSW frame containing DR=1 during A-BFT, and wait for the one containing beamforming feedback information during DTI. Probe responded. In addition, when DRS=0, the STA can also perform DTI sector scanning. In this way, the STA can omit waiting for a certain period of time, and can shorten the delay caused by discovery.

<Modification 1-2> During the A-BFT period, the STA100 may send the SSW frame including a field or sub-field indicating the type of the discovery request.

FIG. 12 is a diagram showing an example of a procedure for STA100 and STA200 to actively scan AP/PCP300. During the A-BFT period, the STA 100 and 200 transmit the SSW frame with the DR Type attached.

Fig. 13 is a diagram showing an example of the format of an SSW frame. Compared with the Discovery Request field of the SSW frame of FIG. 4 which is 1 bit, the Discovery Request field of the SSW frame of FIG. 13 contains more than 2 bits.

STA200 sets the value of the Discovery Request field to 2 (Discovery request(+Multi-band (multi-band))) and sends the SSW frame, the AP/PCP300 that received the SSW frame is in DTI, so that the Probe response contains Multi- The band element is transmitted.

When STA200 receives a Probe response containing Multi-band elements, it obtains information about AP/PCP300 in a frequency band (such as 2.4GHz band, 5GHz band) that is different from the active scanning frequency band (such as 60GHz band) (such as 2.4GHz band). The wireless channel number used by BSS).

After the STA200 establishes a connection with the AP/PCP300 in the 60GHz frequency band, for example, it can also send Probe request or connection request information to the AP/PCP300 in a frequency band different from 60GHz (such as the 2.4GHz frequency band) based on the information obtained by the Multi-band element. Box to establish a connection in the 2.4GHz frequency band.

The 2.4GHz band connection can also be used as an alternative connection when the 60GHz band is cut off. STA200 can determine the channel for transmitting the probe request frame in the 2.4GHz band or connecting the request frame according to the information of the Multi-band element. Therefore, STA200 can shorten the discovery time in the 2.4GHz band by scanning the matching channels in the 2.4GHz band.

In addition, when STA100 sets the value of the Discovery Request field to 3 (Discovery request(+Neighbor Report)) and transmits the SSW frame, the AP/PCP300 that received the SSW frame is in DTI, so that the Probe response contains The Neighbor Report element is transmitted.

When STA100 receives a Probe response that includes Neighbor Report elements, it can obtain information about other APs/PCP300s around the AP/PCP300.

The STA100 can also select a channel with a higher probability of discovering other APs/PCPs through active scanning based on the Neighbor Report elements, for active scanning. In this way, the delay in discovering other AP/PCP300 can be shortened.

In this way, the STA100 and 200 can also request the AP/PCP300 for the types of additional elements included in the Probe request by appropriately setting the value of the Discovery Request field of the SSW frame.

As shown in Figure 13, the value of the Discovery Request field can also be associated with the presence or absence and type of the requested element. In addition, the Discovery Request may be defined as a bitmap, and the bits may be associated with the presence or absence of requirements for each element. For example, the first bit is the presence or absence of Discovery Request, the second bit is the presence or absence of Multi-band element requirements, and the third bit is the presence or absence of Neighbor report element requirements, and 1: Yes, 0: No. It's also possible.

<Modification 1-3> STA100 and STA200 can also send the field or sub-field indicating the number of sub-fields of TRN-R (Receive training) included in the SSW frame during A-BFT. .

FIG. 14 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300. In the SSW frame sent by STA2 during A-BFT, TRN=1 is attached. In the Probe response to STA2, the TRN-R subfield is added.

Fig. 15 is a diagram showing an example of the format of an SSW frame. Compared with the SSW frame of FIG. 4, the SSW frame of FIG. 15 includes the Number of TRN-R sub-field, and the Reserved sub-field has a small number of bits.

The STA200 transmits the Number of TRN-R sub-field of the SSW frame in FIG. 15 to include the value corresponding to the number of receiving antenna sectors of the STA200. For example, 16 times the value of the Number of TRN-R subfield can also represent the number of receiving sectors of STA200.

When STA200 sets the value of the Number of TRN-R sub-field to 1 or more and sends an SSW frame, the AP/PCP300 that received the SSW frame is in DTI and appends the TRN field containing the TRN-R sub-field to The Probe responds and sends it, where the number of the aforementioned TRN-R sub-field corresponds to the value of the Number of TRN-R sub-field.

When the STA200 receives a Probe response with a TRN field attached, it can also use the receiving sector switched for each TRN field to receive the TRN-R subfield, measure the reception quality, and perform the BFT of the receiving antenna. STA200 can also select the best receiving antenna and receiving sector by receiving beamforming.

When the STA200 has the relationship between the directivity characteristics of the transmitting antenna and the directivity characteristics of the receiving antenna, when it has a known antenna pattern reciprocity (Antenna Pattern Reciprocity), etc., according to the beamforming result of the receiving antenna, select the best transmitting antenna and Transport sector.

Furthermore, antenna reciprocity means that when STA200 has multiple transmitting antennas and multiple receiving antennas, the antenna number to which the best transmission sector belongs, and the antenna configuration that is the same as the antenna number to which the best receiving sector belongs is increased. .

For example, the first transmitting antenna and the first receiving antenna have the same coverage (for example, the communication area is in the front direction), the second transmitting antenna and the second receiving antenna have the same coverage (for example, the communication area is in the back direction), and the first When the coverage areas of the transmitting antenna and the first receiving antenna and the second transmitting antenna and the second receiving antenna are less overlapped, the STA200 has antenna reciprocity. Furthermore, the first transmission antenna and the first reception antenna may be an antenna shared by the first transmission/reception. In addition, the second transmission antenna and the second reception antenna may be an antenna shared by the second transmission/reception.

Furthermore, the antenna mode reciprocity means the sector number of the best transmission sector, and the antenna configuration which is the same as the sector number of the best reception sector and has a higher probability. For example, the first transmitting antenna and the first receiving antenna have the same directivity pattern. Also, for example, the first transmission/reception shared antenna (antenna array in FIG. 8) has the same directivity pattern during transmission and reception.

STA200 uses the TRN-R subfield to perform BFT of the receiving antenna and select the best receiving sector. Therefore, the STA200 can improve the communication performance with the AP/PCP300, and perform the subsequent processing of the Probe response (for example, the reception of the connection response frame not shown) with high speed and/or low error rate.

In addition, the STA200 uses the TRN-R subfield to perform the BFT of the receiving antenna, and uses the result to select the best transmission sector. Therefore, even when the STA200 is not receiving the SSW-FB frame, it can still improve the communication performance with the AP/PCP300, with high speed and/or low error rate for the subsequent processing of the Probe response (such as the connection request message not shown) Transmission of the box).

<Modification 1-4> STA100 and STA200 can also send an SSW frame containing the SIFS turnover field or sub-field during the A-BFT period.

FIG. 16 is a diagram showing an example of a procedure for STA100 and STA200 to actively scan for AP/PCP300. In Figure 16, the SSW frame sent by STA200 during A-BFT has SIFS=1 attached.

Fig. 17 is a diagram showing an example of the format of an SSW frame. Compared with the SSW frame of Fig. 4, the SSW frame of Fig. 17 includes the SIFS Turnover sub-field, and the Reserved sub-field has a small number of bits.

Fig. 18 is a diagram showing another example of the format of the SSW frame. Compared with the SSW frame of FIG. 17, the SSW frame of FIG. 18 includes a Discovery Request Type field.

STA100 and STA200 can also set the value of the Discovery Request Type field of FIG. 18 to 0 instead of setting the value of the Discovery Request field of FIG. 17 to 0 to send the SSW frame. STA100 and STA200 can also set the value of the Discovery Request Type field of Figure 18 to 1, instead of setting the value of the Discovery Request field of Figure 17 to 1 and the value of the SIFS Turnover field to 0 to send SSW messages frame.

STA100 and STA200 can also set the value of the Discovery Request Type field of Figure 18 to 2, instead of setting the value of the Discovery Request field of Figure 17 to 1, and the value of the SIFS Turnover field to 1, to send SSW messages frame. The value "3" of the Discovery Request Type field is Reserved.

The SSW frame of FIG. 18 can also use the Reserved setting (the value of the Discovery Request Type field is 3) for future function expansion.

When AP/PCP300 receives an SSW frame with the value of the SIFS Turnover subfield set to 1, in DTI, set the destination address of the Probe response to, for example, the unicast address for STA200 to send Probe responded.

When STA200 receives a Probe response whose destination address includes a unicast address, it sends an Ack frame after SIFS time (3msec). Before transmitting the Ack frame, the STA200 analyzes the beamforming feedback information contained in the Probe response to determine the best sector, and sets the transmission sector to the best sector to transmit the Ack frame.

FIG. 19 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300.

When AP/PCP300 receives the SSW frame with the value of the SIFS Turnover subfield set to 0, in DTI, the destination address of the Probe response is set to the broadcast address to send the Probe response.

When STA100 receives a Probe response whose destination address includes a broadcast address, it determines whether the address of the beamforming feedback information contained in the Probe response (the MAC address field in Figure 29 described later) is targeted at STA100, which is based on STA100. When it comes to the object, analyze the beamforming feedback information to determine the best sector.

When the STA200 receives a Probe response with a destination address including a unicast address in DTI, it analyzes the beamforming feedback information and sets the transmission sector in SIFS time, and then performs Ack transmission (not shown). By transmitting Ack, STA200 can communicate with high reliability. For example, the AP/PCP300 can also send a Probe response whose destination address includes a unicast address, and retransmit the Probe response when the Ack frame is not received after the SIFS time.

When STA100 receives a Probe response with a destination address including a broadcast address in DTI, it can also analyze the beamforming feedback information at a time above SIFS. In this way, even an STA with low processing capability can still perform the reception processing of the Probe response including the beamforming feedback information to complete the discovery.

When AP/PCP300 receives an SSW frame with the value of the SIFS Turnover subfield set to 0 from STA100 during A-BFT, it can also send the SSW-FB frame to STA100, and in DTI, the Probe response does not include Beam feedback information, the destination address is set to the unicast address for STA100, and the Probe response is sent.

STA100 analyzes the beamforming feedback information after receiving the SSW-FB frame. Therefore, the analysis of the beamforming feedback information during reception of the Probe response can also be omitted. In this way, the STA100 can still transmit the Ack frame after the SIFS time even if the processing power is low.

When AP/PCP300 receives the SSW frame with the value of the SIFS Turnover sub-field set to 0 from STA100, and omits sending the SSW-FB frame to STA100, it can also send beamforming information containing STA100 and change the destination address Probe response set to broadcast address.

STA100 and STA200 can also set the value of the SIFS Turnover sub-field according to the processing capability of beam feedback information. In this way, even when the processing capability for beam feedback information is low, the reception processing of the Probe response including the beamforming feedback information can still be performed. Therefore, the delay required for discovery can be shortened.

<Modification 1-5> FIG. 20 is a diagram showing an example of a procedure for STA to perform active scanning for AP/PCP. As shown in FIG. 20, the STA 200 can also send a Short SSW (shortened SSW) packet containing a field indicating the discovery request during the A-BFT period to replace the SSW frame.

Fig. 21 is a diagram showing an example of the format of a Short SSW packet. The field indicating the discovery request is the same as the discovery request sub-field in Figure 4.

The packet length of the Short SSW packet is shorter than that of the packet containing the SSW frame. Therefore, during the A-BFT period, the STA200 switches the transmission sector for each Short SSW packet to transmit more Short SSW packets than the SSW frame. Since STA200 can perform training for many transmission sectors during A-BFT, the accuracy of beamforming is improved. Therefore, the communication quality with the AP/PCP300 (after the Probe response is received) is improved.

In addition, since the Short SSW packet transmitted by the STA 200 has a short packet length, the probability of causing interference to other STAs (such as STA 100 not shown) and/or receiving interference from other STAs is reduced. As a result, the probability of AP/PCP300 receiving valid SSW frames and Short SSW packets from multiple STAs increases.

The STA200 sets the field indicating the discovery request of the Short SSW packet shown in FIG. 21 to DR=1 to transmit the Short SSW packet. When AP/PCP300 receives valid SSW frames and Short SSW packets from multiple STAs, it performs the following processing. That is, the AP/PCP300 sets the field indicating the discovery request of the SSW frame or Short SSW packet to DR=1 and transmits the STA, and transmits the Probe response frame containing the BF feedback. STA200 can receive Probe response frame to complete the BFT and discovery of AP/PCP300.

In this way, the STA 200 transmits a Short SSW packet containing a field indicating the discovery request. Therefore, a plurality of STAs receive the probe response frame when performing BFT during the A-BFT period, and complete the BFT for AP/PCP300 and the delay until discovery will be shortened with a high probability.

<Modification 1-6> During the A-BFT period, the STA200 can also send a Short SSW packet containing a field indicating the discovery request and a control trailer to replace the SSW frame.

FIG. 22 is a diagram showing an example of a procedure for STA 200 to perform active scanning for AP/PCP 300. In Figure 22, the Short SSW packet transmitted by STA2 during the A-BFT period has DR=1 attached.

Fig. 23 is a diagram showing an example of the format of a Short SSW packet. In Figure 20, the Short SSW packet (general Short SSW packet) used by STA200 includes L-STF (Legacy Short Training Field) and L-CEF (Legacy Channel Estimation Field). )), L-Header (Legacy Header), Payload. Furthermore, FIG. 21 is a diagram showing the Payload format of the Short SSW packet. Compared with the Short SSW packet of FIG. 20, the Short SSW packet of FIG. 23 includes a control tail.

The control tail contains additional information for discovery: Discovery Criteria field, Reserved field, and error detection code field (CTCS: Control Trailer Check Sequence). The Discovery Criteria field includes the BSS Type subfield, Short SSID (Service Set IDentifier) subfield, and RNS Info subfield.

STA200 sets the value of the BBS Type sub-field to the value representing Infrastructure BSS (BSS Type=3), and sends Short SSW packets. AP/PCP300 responds to STA200 when BSS (Basic Service Set) is Infrastructure BSS (Probe response transmission), BSS (Basic Service Set) is not Infrastructure BSS (such as PBSS (Personal BSS, BSS Type=2) or IBSS) (independent BSS (independent BSS), BSS Type=1)), the response to STA200 can also be omitted.

AP/PCP300 can also respond to STA200 when the value of the BSS Type subfield of the received Short SSW packet indicates the same type as the BSS of AP/PCP300, and omit the response when it indicates a different type.

STA200 can also select the connected BSS according to the communication application software, and set the value of the BSS Type sub-field. In this way, the response from unintentionally connected access points is suppressed, the delay of discovery is reduced, and unnecessary transmission by AP/PCP300 is reduced.

For example, when the application software used by STA200 is an Internet browser, STA200 can also be connected to the access point of Infrastructure BSS used to transmit IP packets. In addition, when the application software used by STA200 is to transmit images on a large screen, STA200 can also be connected to the PCP of the PBSS for one-to-one communication with the display.

The STA200 can also set the value of the Short SSID field to the 32-bit hash value of the SSID (Service Set IDentifier) (identifier identifying the BSS) of the access point to be connected to, and transmit the Short SSW packet.

AP/PCP300 can also respond to STA200 when the value of the Short SSID subfield of the received Short SSW packet is consistent with the hash value of the AP/PCP300's BSS SSID, and omit the response to STA200 when it is inconsistent.

The STA200 specifies the AP/PCP for discovery from, for example, a list of SSIDs of neighboring APs/PCPs provided by other APs/PCPs (not shown), or SSID values obtained through other communication methods. In this way, processing for responses from non-designated AP/PCP can be omitted, and the delay in discovery can be shortened.

STA200 determines the value of the RSN Info field by including a part of the field in the RSN element specified by the 11ad specification. The value of the RSN Info field contains information related to the support and/or parameters of the security function (for example, privacy, authentication) of the wireless connection.

AP/PCP300 can also respond to STA200 when it supports the security function shown in the RSN Info column of the received Short SSW packet, and omit the response to STA200 when it does not support it.

In this way, the STA200 sends a Short SSW frame containing the value of the Discovery Criteria field. In this way, it is possible to omit the processing of the AP/PCP from the BSS that is not suitable for the application software, or the response of the non-designated AP/PCP, and the delay of discovery can be shortened.

<Modification 1-7> During the A-BFT period, the PCP/AP300 can also transmit the Discovery Request Ack field, which indicates that it has received an SSW frame containing DR=1, to be included in the SSW-FB frame.

FIG. 24 is a diagram showing an example of a procedure for STA 100 to perform active scanning for AP/PCP 300. In Figure 24, the SSW field transmitted by STA100 during A-BFT has DR=1, and the SSW-FB field transmitted by AP/PCP300 during A-BFT has DRA=1.

Fig. 25 is a diagram showing an example of the format of the SSW-FB frame. The SSW-FB frame includes the Frame Control field, the Duration field, the RA field, the SSW Feedback (SSW-FB) field, the BRP Request field, and the Beamformed Link Maintenance field. Maintain) field, FCS field.

The SSW Feedback field includes the Sector Select subfield, DMG Antenna Select subfield, SNR Report subfield, Poll Required subfield, Discovery Request ACK (DRA) subfield, and Reserved subfield.

During the A-BFT period, when PCP/AP300 receives an SSW frame containing DR=1 from STA100, it sets the value of the Discovery Request Ack sub-field to the SSW-FB frame with DRA=1 and sends it to STA100.

In addition, when PCP/AP300 receives an SSW frame containing DR=0 from STA100 during the A-BFT period, it sets the value of the Discovery Request Ack subfield to the SSW-FB frame with DRA=0 and sends it to STA100.

Also, when PCP/AP300 receives an SSW frame containing DR=1 from STA100 during A-BFT, and does not send a Probe response to STA100, set the value of the Discovery Request Ack subfield during A-BFT The SSW-FB frame with DRA=0 is sent to STA100.

Furthermore, "when PCP/AP300 does not send Probe response to STA100" includes, for example, the case where the function of sending Probe response is not supported even if an SSW frame containing DR=1 is received (refer to Embodiment 1).

In addition, "PCP/AP300 did not send Probe response to STA100", for example, the value of the Discovery Criteria field (refer to Figure 23) contained in the SSW frame containing DR=1 is inconsistent with the conditions of PCP/AP300 ( For example, the BSS Type is different).

Furthermore, when the PCP/AP300 does not receive the SSW frame, it does not need to transmit the SSW-FB frame.

When the STA100 receives the SSW-FB frame containing the Discovery Request Ack subfield, it determines whether to wait for the Probe response in DTI.

STA100 waits for Probe response when the value of the received Discovery Request Ack subfield is DRA=1. In this way, the STA 100 can avoid unnecessary transmission of Probe requests.

When the value of the received Discovery Request Ack subfield is DRA=0, STA100 performs the transmission requested by the Probe. In this way, the STA 100 can avoid the delay caused by unnecessary waiting for the Probe response.

AP/PCP300 sets the value of the Discovery Request Ack subfield to DRA=1, and when sending the SSW-FB frame to STA100, it will not send the Probe response to STA100 until it receives the Probe request. In this way, the AP/PCP300 can avoid unnecessary transmission of Probe responses.

<Variation 1-8> PCP/AP300 can also transmit SSW-FB frame during A-BFT, and then transmit SSW-FB frame in DTI, which means that it has received SSW frame with DR=1. A frame (for example, ATIM (announcement traffic indication message) frame or SSW-ACK frame).

FIG. 26 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300.

AP/PCP300 can also receive SSW frames with DR=1 from STA100 and STA200 during A-BFT. The AP/PCP300 can also transmit the SSW-FB frame to any one of the transmission source STAs of the SSW frame (STA100 in FIG. 26) during the A-BFT period.

AP/PCP300 can also send SSW-ACK frame to STA200 in DTI. AP/PCP300 can also send SSW-ACK frames to STA200 that has not sent SSW-FB frames among the source STA100 and 200 of SSW frames.

Furthermore, AP/PCP300 can also send ATIM frame to STA200 in DTI instead of SSW-ACK frame.

When STA200 receives the SSW-ACK frame from AP/PCP300, it waits for Probe response. When the STA200 does not receive the SSW-ACK frame from the AP/PCP300, it can also determine that the BFT during the A-BFT period is not completed, and perform other procedures, such as DTI beamforming. In this way, the STA200 can avoid waiting for Probe response, and can avoid delay increase. In addition, the STA200 shifts to the sleep (power saving) mode where it stops waiting before the next BTI, so that power consumption can be reduced.

Furthermore, AP/PCP300 can also send SSW-ACK frame at the beginning of DTI. The waiting time of the SSW-ACK frame is shorter than the waiting time of the Probe response. Therefore, the STA200 can determine whether the BFT is completed as soon as possible, which can shorten the waiting time.

In addition, AP/PCP300 can also set ATI (Announcement transmission interval) between the A-BFT period and DTI, and transmit the ATIM frame. ATI can also be set to a shorter period than DTI. The waiting period of ATI's ATIM frame is shorter than the waiting time of DTI's Probe response, so STA200 can judge whether the BFT is completed as soon as possible, which can shorten the waiting time.

<Modification 1-9> PCP/AP300 can also respond to Probes targeting STA100 and STA200 in DTI, similarly to the transmission of DMG beacons or the transmission of SSW frames, using SBIFS (Short Beam Forming Interframe Space (Short beamforming frame interval)) Continuous transmission at intervals (1msec).

FIG. 27 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300.

During the A-BFT period, the PCP/AP300 receives SSW frames containing DR=1 from multiple STAs.

In DTI, PCP/AP300 will send Probe responses for each STA at short intervals such as SBIFS interval (1msec) or SIFS interval (3msec).

Furthermore, AP/PCP300 can also set the destination address of Probe response as the broadcast address. In this way, the STA that receives the Probe response can omit the transmission of the ACK frame, so the AP/PCP300 can transmit the Probe response at short intervals.

In this way, the PCP/AP300 can efficiently transmit Probe responses to multiple STAs, and the STA100 and STA200 can shorten the waiting time for Probe responses.

<Modification 1-10> The PCP/AP300 can also send the beamforming feedback information of multiple STAs (such as STA100 and STA200) in DTI, which is included in the Probe response.

FIG. 28 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300.

FIG. 29 is a diagram showing an example of the format of Probe response. Compared with the Probe response in Figure 5, the Probe response in Figure 29 adds the MAC address field to the Beamforming Feedback element.

As shown in Figure 29, the AP/PCP300 can also enable the Probe Response frame body of the Probe response, including multiple Beamforming Feedback frames. For example, AP/PCP300 can also enable the Probe Response frame body to include 2 Beamforming Feedback frames, make the first Beamforming Feedback frame include beamforming feedback information about STA100, and set the MAC address field to that of STA100 MAC address. In addition, AP/PCP300 can also enable the second Beamforming Feedback frame to include beamforming feedback information about STA200, and set the MAC address field to the MAC address of STA200.

AP/PCP300 can also make STA100 and STA200 beamforming feedback information when the sector used for the transmission of the frame targeting STA100 and the sector used for the transmission of the frame targeting STA200 are the same sector Contained in 1 Probe response, and use the same sector to transmit. For example, when STA100 makes the best sector of AP/PCP300 specified by the feedback information contained in the SSW frame and the optimal sector of AP/PCP300 specified by the feedback information contained in the SSW frame of STA200 the same sector AP/PCP300 can also set the same sector in the sector used for the transmission of the frame targeted by STA100 and the sector used for the transmission of the frame targeted by STA200.

In this way, the AP/PCP300 makes the information of multiple Probe responses targeted at STAs included in each Beamforming Feedback frame of a Probe response. In this way, the delay required for the transmission of a plurality of Probe responses (including carrier sense and backoff of each frame) can be shortened to the delay required for the transmission of one Probe response.

<Modification 1-11> The PCP/AP300 can also send the information requested by the Probe response from the STA100 in the Probe response in DTI.

FIG. 30 is a diagram showing an example of a procedure for STA 100 to perform active scanning for AP/PCP 300.

In DTI, PCP/AP300 makes the information requested from STA100 for Probe response included in the Probe response and sent. For example, in the Beamforming Feedback field of Probe response in Figure 29, add a 1-bit Solicit Probe Response subfield, and set the value of the subfield to 1. Beamforming Feedback is an example. The Solicit Probe Response subfield can also be added to fields other than the Beamforming Feedback field. Also, the Reserved sub-fields of fields other than the Beamforming Feedback field can be replaced with Solicit Probe Response sub-fields.

When the STA100 receives the Probe response with the Solicit Probe Response subfield set to 1, after obtaining the transmission right (for example, performing carrier sensing), the Probe response is transmitted to the AP/PCP300.

AP/PCP300 omits the transmission of Probe request for STA100 and receives Probe response. In this way, the AP/PCP300 can reduce the waste of wireless resources and obtain the information of the STA100.

<Modification 1-12> The PCP/AP300 can also send a TRN field containing the TRN-R subfield to the Probe response in DTI. Regarding the TRN-R sub-field, since it has been described in the description of FIG. 22, the description here is omitted.

FIG. 31 is a diagram showing an example of a procedure for STA100 and STA200 to perform active scanning for AP/PCP300.

STA200 can also switch the receiving sector for each TRN-R sub-field received in DTI, thereby performing receive beamforming training. STA200 decides the best sector based on the result of receiving beamforming training.

Furthermore, when the STA200 has antenna mode reciprocity, and when the correspondence between the transmission antenna and the reception antenna's directivity mode is known, the best transmission sector can also be selected from the training result of the receive beamforming. Compared with the feedback information that the Probe responds, the optimal transmission sector determined in this way can become highly accurate. Therefore, STA200 can improve the quality of communication.

Fig. 32 is a block diagram showing an example of the configuration of a communication device (AP/PCP300 and STA200). Although it is the same as FIG. 8 and FIG. 9, the PHY transmission circuit and the PHY reception circuit are described in detail.

When AP/PCP300 transmits Probe response in DTI, the message generating circuit of MAC processor generates the frame data of Probe response (refer to Figure 5) and inputs to the PHY transmission circuit. The PHY transmission circuit generates frame data by encoding and modulating the frame data.

In addition, the PHY transmission circuit includes a TRN subfield generator. The TRN sub-column generating unit generates TRN-R sub-columns. The PHY transmission circuit combines the frame data with the TRN-R sub-field, converts it into an analog signal in D/A, and transmits it from the transmission RF circuit.

When the STA200 receives the Probe response with the TRN-R sub-field attached, the BFT module of the MAC processor controls the PHY receiving circuit to switch the receiving sector for each TRN-R sub-field. As an example of the control signal (CONTROL) output from the MAC processor to the PHY receiving circuit, it includes a list of receiving sector numbers used for receiving in the TRN-R sub-column.

The PHY receiving circuit controls the receiving RF circuit and controls the switching of the receiving sector based on the control signal input from the MAC processor and the information attached to the PHY header of the Probe response.

In addition, the PHY receiving circuit includes a TRN sub-field processor. The TRN sub-field processor calculates the reception quality of each receiving sector (for example, received signal power, S/N ratio) from the received signal in the TRN-R field.

The PHY receiving circuit notifies the MAC processor of the reception quality of each receiving sector calculated by the TRN sub-field processor (not shown in the block diagram). The BFT module of the MAC processor can also determine the best receiving sector from the receiving quality of each receiving sector, and then determine the best transmitting sector from the information of the antenna mode reciprocity.

(Embodiment 2) In Embodiment 1, the case where STA performs BFT (SSW frame transmission) during A-BFT and AP/PCP reception is explained. In Embodiment 2, the actions of STA and AP/PCP are explained in the following cases: (1) The STA does not perform BFT (SSW frame transmission) during A-BFT, and (2) STA is during A-BFT BFT (Transmission of SSW Frame) is performed, but due to competition with other STAs' transmission, AP/PCP does not receive the SSW frame, or a reception error occurs.

FIG. 33A is a diagram of an example of a program of Embodiment 2 in which STA 100 performs active scanning for AP/PCP 300.

FIG. 33A shows the situation where the AP transmits the SSW-FB frame, and FIG. 33B shows the situation where the AP does not transmit the SSW-FB frame.

In the BTI of FIG. 33A and FIG. 33B, the AP/PCP 300 changes the transmission sector for each DMG beacon and transmits more than one DMG beacon.

In the BTI of FIG. 33A and FIG. 33B, the STA 100 receives the DMG beacon. Furthermore, other STAs (STA200) can also receive DMG beacons in the same BTI.

Examples of the operation of STA100 during the A-BFT period are as follows. (1) When STA100 does not perform BFT (transmission of SSW frame) during A-BFT, AP/PCP300 does not transmit SSW-FB frame. (2) The STA performs BFT (SSW frame transmission) during A-BFT, but due to competition with other STA transmissions, AP/PCP does not receive the SSW frame, or when a reception error occurs, the AP/PCP PCP300 does not transmit SSW-FB frames in (1) and (2). (3) During A-BFT, STA100 transmits an SSW frame without DR=1. AP/PCP300 transmits an SSW-FB frame, but STA100 does not receive it.

Under the conditions of (1), (2), and (3) above, the following procedures can also be applied to STA100.

In DTI, STA100 changes the transmission sector every SSW frame to transmit the SSW frame containing the field (DR=1) indicating the discovery request. Since the format of the SSW frame is the same as that of FIG. 4, the description is omitted here.

AP/PCP300 receives more than one SSW frame in DTI.

The AP/PCP300 determines the transmission sector ID in the SSW frame with good reception quality in the received SSW frame as the best sector for the transmission target STA.

The AP/PCP300 makes the SSW-FB frame containing the information of the determined best sector and sends it to STA100.

When STA100 receives the SSW-FB frame, it uses the best sector included in the SSW-FB frame to transmit the SSW-ACK frame.

When the SSW frame received by the DTI contains a field (DR=1) indicating the discovery request, the AP/PCP300 receives the SSW-Ack for the SSW-FB, and obtains a transmission opportunity (TXOP) to send a Probe response. AP/PCP300 can also make Probe response, including beamforming feedback information. In addition, AP/PCP300 can also omit beamforming feedback information to shorten Probe response.

In DTI, STA100 receives a detection response frame containing beamforming feedback (Beamforming Feedback element), and determines the best fan for communication with AP/PCP300 based on the information contained in the beamforming feedback (such as the value of the Sector Select field) Area. Furthermore, since the STA100 receives the Probe response from the AP/PCP300, it is completed (successfully) based on the discovery of the active scanning procedure for the AP/PCP300.

STA100 performs BFT (Sector Scan) during A-BFT. Even if it does not receive the SSW-FB frame, it can still receive Probe responses in DTI. In this way, the STA 100 can omit the retry of the BFT, which can shorten the delay required for discovery. In addition, the STA 100 can omit the transmission required by the Probe, which can shorten the delay required for discovery.

FIG. 33B is a diagram showing an example of a procedure of Embodiment 2 in which STA 100 performs active scanning for AP/PCP 300.

Before the AP/PCP300 sends the SSW-FB frame to the STA100 with the best sector information in the DTI, if the AP/PCP300's receiving antenna detects signals from other STAs (not shown), In order to avoid the conflict of transmission signals, SSW-FB frames are not transmitted.

In addition, before or after receiving the SSW frame from STA100, AP/PCP300 receives RTS frame and DMG CTS frame from other STA200 not shown in the figure, and detects that STA200 obtains the transmission right, and then the transmission right of STA200 is not yet expired. When full, no SSW-FB frame is sent.

Since STA100 does not receive the SSW-FB frame from AP/PCP300, it does not send the SSW-ACK frame.

When the AP/PCP300 receives the SSW frame, including the field that indicates the discovery request (DR=1), the transmission right held by the STA100 (STA100 is used for the transmission of the SSW frame and the reception of the SSW-FB frame ) After finishing, obtain the transmission right with STA100, so that the Probe response includes beamforming feedback information and transmits.

Furthermore, when the AP/PCP300 transmits the SSW-FB frame, but does not receive the SSW-ACK frame from the STA100, the Probe can also be sent in response to including beamforming feedback information.

In DTI, STA100 receives a Probe response that includes beamforming feedback (Beamforming Feedback element), and determines the best sector for communication with AP/PCP300 based on the information contained in the beamforming feedback (such as the value of the Sector Select field). In addition, since the Probe response from the AP/PCP300 is received, the discovery of the active scanning procedure for the AP/PCP300 is completed (successful).

In FIG. 33B, STA100 performs BFT (for example, sector scan) in DTI. Even when it does not receive the SSW-FB frame from AP/PCP300, it can still receive AP/PCP300 Probe response. In this way, the STA100 can omit the retry of the BFT, which can shorten the delay until the start of the data communication caused by the discovery. In addition, STA100 can also omit the transmission of Probe request, which can shorten the delay to the start of data communication caused by discovery.

FIG. 34 is a flowchart showing an example of a discovery procedure by the STA 100 in FIGS. 33A and 33B.

First, STA100 starts to discover (S101).

Next, the STA 100 is in the BTI and transmits the DMG beacon from the AP/PCP 300 (S102). Furthermore, the DMG beacon may also be transmitted by the AP/PCP300 for sector scanning. In short, the AP/PCP300 can also switch the transmission direction of the wireless signal (DMG beacon) by switching the transmission sector according to each DMG beacon, and transmit more than one DMG beacon. In addition, AP/PCP300 can also send information elements and fields that indicate whether there is an A-BFT period scheduled after BTI, which is included in the DMG beacon.

Next, in STA100, when there is no A-BFT period scheduled (S103: NO-T1), the flow proceeds to S201, and STA100 performs DTI beamforming. In addition, when the STA100 has not obtained the transmission opportunity (TXOP) (S103: NO-T2), the process returns to S102, and the STA100 does not perform DTI beamforming, and it can wait for the next BTI.

In S201, STA100 changes the transmission sector for each SSW frame in DTI for BFT in S201, to transmit the SSW frame containing the field (DR=1) indicating the discovery request (refer to FIG. 33A and FIG. 33B). The format of the SSW frame is the same as Figure 4. Here, STA100 can also determine the best sector of AP/PCP300 from the quality of the S102 DMG beacon received at BTI, and make the sector ID of the best sector included in the Sector Select subframe of the SSW frame And transmit.

In addition, the AP/PCP300 receives the SSW frame of S201 that contains the field (DR=1) indicating the discovery request, determines the best sector of STA100, prepares to communicate with STA100, and stores the information of the best sector in the memory (S202).

Then, AP/PCP300 transmits the SSW-FB frame to STA100 (S203). AP/PCP300 can also send SSW-FB frames to other STAs (refer to Figure 33A). In addition, the AP/PCP300 can also use the best sector notified by the SSW frame to transmit the SSW-FB frame. In addition, AP/PCP300 can also transmit the best sector information of STA100 included in the SSW-FB frame. Furthermore, as mentioned above, when the AP/PCP 300 detects, for example, a signal from another STA (not shown), it sometimes does not transmit the SSW-FB frame (refer to FIG. 33B).

In addition, when the STA100 does not receive the SSW-FB frame from the AP/PCP300 (S204: NO), it proceeds to S211 (S205: A-3) described later, and waits for the reception of the Probe response. Furthermore, when the STA100 does not receive the Probe response within the predetermined time, the flow proceeds to S201 in the same way as the conventional 11ad standard STA, and the STA100 tries sector scan again in DTI (S205: A-1) (in FIG. 33A) And FIG. 33B is not shown), or the flow proceeds to S102, and the STA100 tries again the sector scan (S205: A-2) during the next A-BFT period (not shown in FIGS. 33A and 33B). Here, the case where the SSW-FB frame is not received also includes the case where the AP/PCP300 does not transmit the SSW-FB frame.

When the STA100 receives the SSW-FB frame from the AP/PCP300 (S204: YES), it prepares to communicate with the AP/PCP300, and stores the information of the best sector contained in the SSW-FB frame in the memory (S206) ( Refer to Figure 33A).

Next, in order to notify the AP/PCP 300 that the SSW-FB frame was received without error, the STA 100 transmits the SSW-ACK frame (S207), and the flow proceeds to S208 described later.

In addition, in S103, when there is no A-BFT period scheduled for STA100 (S103: YES), STA100 transmits SSW frame with AP/PCP300 as the transmission destination during the A-BFT period (S104) (in Figure 33A, (Not shown in Figure 33B). Furthermore, the STA100 can also send SSW frames for sector scanning. In short, STA100 can also switch the transmission sector for each SSW frame, switch the transmission direction of the wireless signal (SSW frame), and transmit more than one SSW frame. Since this is a response to AP/PCP300's sector scan using DMG beacons, and STA100 performs sector scan, it is called response BFT. In addition, the STA 100 can also determine the best sector of the AP/PCP 300 according to the reception quality of the DMG beacon received in the BTI, and include the best sector information (such as sector ID) in the SSW frame for transmission.

When the AP/PCP300 does not receive the SSW frame of S104 (S105: NO), the process skips the transmission of the SSW-FB frame of STA100 and proceeds to S201. The case where the SSW frame is not received may also include the case where there is a reception error and/or the case where the received power is lower than the threshold.

When the AP/PCP300 receives the SSW frame of S104 (S105: YES), it determines the best sector of STA100, prepares to communicate with STA100, and stores the best sector information in the memory (S106).

Then, AP/PCP300 transmits the SSW-FB frame to STA100 (S107). Furthermore, AP/PCP300 can also send SSW-FB frames to other STAs that have received SSW frames. In addition, the AP/PCP300 can also use the best sector notified by the SSW frame to transmit the SSW-FB frame. In addition, AP/PCP300 can also transmit the best sector information of STA100 included in the SSW-FB frame.

In addition, if the STA100 does not receive the SSW-FB frame corresponding to the S107 of the SSW frame transmitted by S104 (S108: NO), the process proceeds to S201 in order to perform beamforming in DTI.

When STA100 receives the SSW-FB frame corresponding to S107 of the SSW frame sent by S104 (S108: YES), it prepares to communicate with AP/PCP300 and will include the information of the best sector in the SSW-FB frame Store in memory (S109).

Then, when STA100 completes S207 or S109, it judges that the initial BFT (success) between AP/PCP300 and STA100 is completed (S208). In short, STA100 judges that the best sector can be used to communicate with AP/PCP300. Furthermore, at this point, it was discovered that it had not been completed yet.

Then, STA100 can also send a Probe request to AP/PCP300 in DTI (S209).

In addition, when the AP/PCP300 receives the Probe request of S208 in DTI and determines that there is no reception error, it sends an ACK frame to STA100 after SIFS (3msec) (S210).

Then, the AP/PCP300 transmits a Probe response (S211). Furthermore, AP/PCP300 can also enable Probe to send in response to information including the best sector of STA100.

In addition, the STA100 receives the Probe response of S211, and when it determines that there is no reception error, it sends an ACK frame after SIFS (3msec) (S212).

Then, the STA100 stores the information (scanning result) of the AP/PCP300 that is included in the Probe response and the BSS managed by the AP/PCP300 in the memory (S213). Furthermore, the MAC processor of the STA100 can also notify the main controller of the scan result.

Then, STA100 completes the above discovery of AP/PCP300 (S214). In order to discover other APs/PCPs (not shown), the STA100 may also be in the same wireless channel, or after switching the wireless channel, transfer to S101 and repeat the discovery.

(Modification of Embodiment 2) In addition, in Figure 33A and Figure 33B, AP/PCP300 can also be used in DTI to display a field that supports the reception of an SSW frame including a field that indicates a discovery request (DR=1) , Included in the DMG beacon and transmitted (refer to the format of the DMG beacon in Figure 11).

In addition, the STA100 can also send a field or sub-field indicating the type of the discovery request in the DTI to be included in the SSW frame (refer to the format of the SSW frame in FIG. 13).

In addition, the STA100 can also transmit a field or sub-field indicating the number of TRN-R sub-fields in the SSW frame in DTI (refer to the format of the SSW frame in FIG. 15). AP/PCP300 can also send the TRN field containing the TRN-R subfield to the Probe response in DTI. The number of the aforementioned TRN-R subfield corresponds to the value of the Number of TRN-R subfield (Refer to the detection response frame in Figure 15).

In addition, the STA100 can also send the SIFS Turnover field or sub-field in the SSW frame in DTI (refer to the format of the SSW frame in FIG. 17).

In addition, the STA 100 can also send a Short SSW packet including the Discovery Request field in the DTI to replace the SSW frame (refer to the format of the Short SSW packet in FIG. 21).

In addition, in the DTI, the PCP/AP300 transmits the Discovery Request Ack field, which indicates that it has received an SSW frame containing DR=1, which is included in the SSW-FB frame.

In the second embodiment of the PCP/AP300, the information requested from the STA100 for a Probe response can be included in the Probe response and sent (refer to Figure 30). When the STA100 receives a Probe response containing information requesting a Probe response, it obtains a transmission opportunity (TXOP) and sends the Probe response to the AP/PCP300.

PCP/AP300 can also send a TRN field containing the TRN-R subfield to the Probe response in DTI (refer to Figure 31). STA100 can also switch the receiving sector for each TRN-R sub-field in DTI to receive the TRN-R sub-field and perform receiving sector training.

When the communication device (STA100) is not scheduled during the A-BFT period (Figure 33A, Figure 33B), and when the BFT during the A-BFT period is not completed, in DTI, change the transmission sector for each SSW frame to transmit The SSW frame containing the field (DR=1) indicating the discovery request. When the communication device (AP/PCP300) receives the SSW frame containing the field (DR=1) indicating the discovery request, it sends a Probe response containing the information of the BFT result to the communication device (STA100).

In this way, the communication device (STA100) can still complete beamforming and discovery even when the communication device (AP/PCP300) does not transmit the SSW-FB frame, or when there is a receiving error of the SSW-FB frame (Figure 33B). Therefore, the period required for discovery can be shortened.

The communication device (STA100) completes beamforming during discovery and becomes a state where it can start communicating with the communication device (AP/PCP300). Therefore, it is possible to shorten the period of time spent in the procedures until the start of data communication.

(Embodiment 3) In Embodiment 1 and Embodiment 2, the STA 100 receives the DMG beacon transmitted by the AP/PCP 300 to perform active scanning (referred to as Discovery Mode=0). In Embodiment 3, the method in which the STA100 starts beamforming by transmitting the DMG beacon and performs active scanning (referred to as Discovery Mode=1) is explained.

FIG. 35 is a diagram showing an example of a procedure of Embodiment 3 in which STA 100 performs active scanning for AP/PCP 300.

In BTI, STA100 switches the transmission sector for each DMG beacon, and transmits the DMG beacon with the value of the Discovery Mode field set to 1.

The AP/PCP300 is in BTI and receives the DMG beacon with the value of the Discovery Mode field set to 1. In addition, the reception quality of the received DMG beacon is measured, and the best sector of the STA 100 is selected.

During the A-BFT period, AP/PCP300 switches the transmission sector for each SSW frame and transmits the SSW frame. AP/PCP300 can also send the best sector information of STA100 included in the SSW frame.

STA100 receives the SSW frame, measures the reception quality of the received SSW frame, and selects the best sector of AP/PCP300 based on the measurement result.

When STA100 receives an SSW frame during A-BFT, it sends an SSW-FB frame with the discovery request field set to 1. STA100 can also include the best sector information of AP/PCP300 in the SSW-FB frame.

When AP/PCP300 receives the SSW-FB frame with the discovery request field set to 1, it obtains a transmission opportunity (TXOP) and sends the Probe response to STA100.

The STA100 receives the Probe response and replies the ACK frame to the AP/PCP300. In this way, STA100 completes the discovery of AP/PCP300.

In this way, when the STA100 is performing an active scan with Discovery Mode=1, it sends an SSW-FB frame containing a field (DR=1) indicating the discovery request. In this way, the STA 100 can omit the transmission of the Probe request and receive the Probe response, which can shorten the time required for discovery.

FIG. 36 is a flowchart showing an example of a procedure (FIG. 35) for STA 100 to perform discovery by active scanning with Discovery Mode=1.

First, STA100 starts to discover (S301).

Next, the STA 100 transmits a DMG beacon with the value of the Discovery Mode field set to 1 in the BTI (S302). In short, the STA100 can also switch the transmission direction of the wireless signal (DMG beacon) by switching the transmission sector for each DMG beacon, and transmit more than one DMG beacon. In addition, the STA100 can also include the information elements and fields indicating whether there is an A-BFT period scheduled after the BTI and include them in the DMG beacon for transmission.

In addition, when the AP/PCP 300 does not receive the DMG beacon of S302 in the BTI (S303: NO), the flow proceeds to S306. At this time, AP/PCP300 does not transmit the S305 frame of S305 described later.

When the AP/PCP 300 receives the DMG beacon of S302 in the BTI (S303: YES), it measures the reception quality of the received DMG beacon, and selects the best sector of the STA 100 based on the measurement result (S304).

Then, the AP/PCP300 transmits the SSW frame to the STA100 during the A-BFT period (S305). Here, AP/PCP300 can also switch transmission sectors for each SSW frame, and transmit more than one SSW frame. In addition, the AP/PCP300 can also send the SSW frame including the information of the best sector of the STA100 (for example, the reception quality measured in S303). Then, the flow proceeds to S306.

In S306, when the STA100 does not receive the SSW frame during the A-BFT period (S306: NO), it can also return to S302, and then transmit the DMG beacon. The situation of not receiving the SSW frame includes: the AP/PCP300 is not transmitting the S305 frame of S305; and/or due to competition with other STA transmissions or insufficient receiving sensitivity, in S306, STA100 does not receive the SSW signal The case of the box and so on. Furthermore, the STA 100 may also end the current wireless channel discovery or discovery of the AP/PCP 300 when the DMG beacon retransmission is performed a predetermined number of times.

In S306, when STA100 receives the SSW frame during A-BFT (S306: YES), it selects the best sector of AP/PCP300. In order to communicate with AP/PCP300, the information of the best sector is stored in Memory (S307).

Next, during the A-BFT period, the STA100 transmits an SSW-FB frame with the field indicating the discovery request set to 1 (DR=1) (S308). Here, the STA100 can also use the slave AP/PCP300 to transmit the SSW-FB frame through the best sector for transmission of the STA100 notified by the SSW frame. In addition, STA100 can also include the best sector information of AP/PCP300 in the SSW-FB frame.

In addition, when the AP/PCP300 does not receive the SSW-FB frame of S308 during the A-BFT period (S309: NO), the process returns to S302, and the AP/PCP300 waits for reception.

When AP/PCP300 receives the SSW-FB frame of S308 during the A-BFT period (S309: YES), in order to communicate with STA100, the best transmission sector of AP/PCP300 included in the SSW-FB frame The information is stored in the memory (S310).

Next, the AP/PCP300 judges that the BFT between its own AP/PCP300 and the STA100 is completed (S311).

Then, when the SSW-FB frame received in S309 indicates that the field of the discovery request is set to 1 (DR=1), the AP/PCP300 sends the Probe response to the STA100 in the DTI (S312).

When STA100 does not receive the Probe response of S312 (S313: NO-1), the process returns to S312, and AP/PCP300 can send Probe response again. Here, the case where the STA100 does not receive the Probe response includes, for example, the case where the STA100 does not send the ACK frame to the AP/PCP300. In addition, when the STA100 does not receive the Probe response in S313 (S313: NO-2), the process returns to S302, and the STA100 may try to transmit the DMG beacon again.

When the STA100 receives the Probe response from the DTI (S313: YES), it sends the ACK frame to the AP/PCP300 (S314).

Then, the MAC processor of the STA100 (refer to FIG. 8) notifies the main controller of the scanning result (for example, the information and reception quality of the AP/PCP300 included in the Probe response) (S315).

Then, the STA 100 judges that the discovery of the AP/PCP 300 is completed (S316).

Furthermore, in Embodiment 3 (FIG. 35), one reserved bit (reserved bit) contained in the SSW-FB frame of the 11ad specification can be changed to a field indicating the discovery request and used.

When the STA100 performs discovery by active scanning with Discovery Mode=1, in step S308, the field indicating the discovery request is included in the SSW-FB frame, and the value of the field is set to 1 for transmission. When AP/PCP300 receives the SSW-FB frame containing DR=1, it sends the Probe response to STA100. In this way, the STA 100 can omit the transmission required by the Probe to complete the discovery of the AP/PCP 300, which can shorten the time required for discovery.

<Modifications of Embodiment 3> <Modifications 3-1> In addition, in Fig. 35, similar to Fig. 30, AP/PCP300 can also include the field of the probe response request from STA100 and send it in the probe response . When the STA100 receives the Probe response from the AP/PCP300 that contains the field requesting the Probe response, it gets the opportunity to send it, and it can also send the Probe response to the AP/PCP300.

<Modification 3-2> In the BTI shown in FIG. 35, the STA100 may include the field (DR=1) indicating the discovery request in the DMG beacon and transmit it instead of the A-BFT period shown in FIG. 35 , The field (DR=1) indicating the discovery request is included in the SSW-FB frame and sent.

FIG. 37 is a diagram showing an example of a procedure for STA 100 to perform active scanning for AP/PCP 300.

In BTI, STA100 transmits a DMG beacon containing a field (DR=1) indicating a discovery request.

When the DMG beacon received by the AP/PCP300 includes DR=1 in the BTI, the SSW frame is transmitted during the A-BFT period. After receiving the SSW-FB frame, the AP/PCP300 obtains the transmission opportunity (TXOP). In DTI, the Probe responds with STA100 is the target transmission.

In Modification 3-1, one reserved bit contained in the DMG beacon of the 11ad specification can be changed to a field indicating the discovery request and used.

In addition, as another method, since the DMG beacon is formulated as Extensible in the 11ad specification, it is also possible to extend the field indicating the discovery request without using the reserved bit. As a result, compared with Embodiment 3 (FIG. 35), since the reserved bit of the SSW-FB frame is not reduced, the reserved bit can be ensured for future extension.

<Modification 3-3> In BTI, STA100 can also include the field indicating the discovery request (DR=1) and the element indicating the discovery criterion (for example, the Requested SSID element) in the DMG beacon and transmit it instead of During A-BFT, the field (DR=1) indicating the discovery request is included in the SSW-FB frame and sent.

FIG. 38 is a diagram showing an example of a procedure for STA 100 to perform active scanning for AP/PCP 300. AP/PCP300 receives the SSW-FB frame during the A-BFT period. When the DMG beacon received at DTI contains DR=1 and meets the discovery criterion, it obtains a transmission opportunity (TXOP) and transmits the Probe response to STA100.

Fig. 39 is a diagram showing an example of the format of a DMG beacon. As shown in Figure 39, compared with the DMG beacon field of the 11ad specification, 1 Reserved bit in the SSW field is used as the Discovery Request field. When the STA100 sets the value of the Discovery Request field to 1, it is also possible to include the Requested SSID element not specified in the 11ad specification in the DMG beacon and transmit it.

The Requested SSID element contains information about the AP/PCP to be discovered. For example, the Requested SSID element contains the SSID field, which contains the value of the AP/PCP SSID. The Requested SSID element can also include a Short SSID field.

In addition, the STA 100 may include the DMG Capabilities element in the DMG beacon and transmit it.

Here, even in the 11ad standard, the DMG Capabilities element can be included in the DMG beacon, but for example, when a STA with a large number of sectors (such as AP/PCP300) uses the DMG Capabilities element, the radio resources required for the transmission of the DMG beacon Increased consumption and poor efficiency.

Furthermore, when STA100 has a smaller number of sectors than AP/PCP300, STA100 may also include the DMG Capabilities element in the DMG beacon with Discovery Mode=1. In this way, the increase in the consumption of wireless resources is suppressed, and the AP/PCP300 can omit the transmission of the Probe request of the STA100 in the acquisition of information about the STA100 (included in the DMG Capabilities element).

Furthermore, the STA100 can replace the Requested SSID element, or in addition to the Requested SSID element, it can also include elements that limit the discovery object (for example, BSS Type, Short SSID, RSN Info in FIG. 23), which are included in the DMG beacon. Transmit.

In this way, since STA100 includes information about the discovery criteria and transmits the DMG beacon with Discovery Mode=1, it can avoid AP/PCP from BSS that is not suitable for application software, or A-BFT period of non-designated AP/PCP Response. Therefore, the mutual competition during the A-BFT period can be avoided, and the increase in the discovery time due to, for example, the reception failure of the SSW frame can be suppressed.

<Modification 3-4> AP/PCP300 can also use a field that indicates whether to support the response field (DR=1) in the SSW-FB frame sent by STA100 during the A-BFT period. , Included in the SSW frame and sent.

FIG. 40 is a diagram showing an example of a procedure for STA 100 to perform active scanning for AP/PCP 300.

During A-BFT, AP/PCP300 uses the field (DRS: Discovery Request Supported) that indicates whether to support the field (DRS: Discovery Request Supported) of the field that indicates the discovery request (DR=1) in the SSW-FB frame sent by STA100, including Send in SSW frame.

When the value of the DRS field of the received SSW frame is 1, STA100 sets the field indicating the discovery request during the A-BFT period to 1 (DR=1), sends the SSW-FB frame, and performs Probe response wait.

When the value of the DRS field of the received SSW frame is 0 (not shown), STA100 sets the field indicating the discovery request during A-BFT to 0 (DR=0), and sends the SSW-FB frame For example, send Probe request to AP/PCP300 instead of waiting for Probe response.

Since STA100 can determine whether to wait for Probe response after transmitting the SSW-FB frame according to the DRS value included in the SSW frame, unnecessary waiting can be avoided and the time required for discovery can be reduced.

<Modification 3-5> During the A-BFT period, the STA100 can also add the SSW-FB frame containing the field (DR=1) indicating the discovery request set to 1 to the control tail and send it. As an example, the control tail can also adopt the format of FIG. 23, and the description here is omitted.

FIG. 41 is a diagram showing an example of a procedure for STA 100 to perform active scanning for AP/PCP 300.

During the A-BFT period, AP/PCP300 receives the SSW-FB frame with the control tail attached. When AP/PCP300 shows that the discovery criterion shown by the value of the control tail is suitable for AP/PCP300 (for example, when the value of Short SSID is the same, BSS Type is the same), it can also transmit Probe response in DTI.

In this way, the STA100 attaches a control tail containing information about the discovery reference, and transmits an SSW-FB frame. Therefore, for example, it can avoid the AP/PCP of the BSS that is not suitable for the application software, or the non-designated AP/PCP from sending Probe responses, which can reduce the interference to other STAs (not shown).

Compared with sending unnecessary Probe responses, the addition of the control tail of the SSW-FB frame consumes less wireless resources and is more efficient.

According to the above, when the communication device (STA) 100 performs an active scan of Discovery Mode=1, the field indicating the discovery request is included in the SSW-FB frame and sent. In this way, the STA 100 can omit the transmission requested by the Probe, and avoid backoff or retransmission processing with a large delay.

(Embodiment 4) In Embodiment 2, when the STA does not perform BFT (SSW frame transmission) during the A-BFT period, and the STA performs BFT (SSW frame transmission) during the A-BFT period, but due to The transmission of other STAs compete with each other, etc. When AP/PCP does not receive the SSW frame or a reception error occurs, the STA100 performs sector scan in DTI to explain the situation. In Embodiment 4, as a form of DTI sector scanning in Embodiment 2, a case where STA100 transmits a DMG beacon with Discovery Mode=1 will be described.

FIG. 42 is a diagram showing an example of a procedure for the STA 100 to perform an active scan for the AP/PCP 300.

In the BTI of Figure 42, AP/PCP300 changes the transmission sector for each DMG beacon to transmit DMG beacons that do not contain DR=1.

In the BTI of FIG. 42, the STA 100 receives the DMG beacon. Furthermore, other STAs (STA200 not shown) can also receive DMG beacons in the same BTI.

STA100 does not perform BFT (SSW frame transmission) during A-BFT, and STA100 performs BFT (SSW frame transmission) during A-BFT, but AP/PCP300 competes with other STAs for transmission. Etc., when the SSW frame is not received, or when the AP/PCP300 has a receiving error, the AP/PCP300 can also omit sending the SSW-FB frame, and use the following procedure.

In addition, when STA100 transmits an SSW frame without DR=1 during A-BFT, and AP/PCP300 transmits an SSW-FB frame, but STA100 cannot receive it, the following procedure can also be used.

The STA100 changes the transmission sector for each DMG beacon to transmit the DMG beacon containing the field (DR=1) indicating the discovery request. STA100 transmits the DMG beacon including the best sector of AP/PCP300.

Fig. 43 is a diagram showing an example of the format of a DMG beacon. The DMG beacon includes, for example, the SSW field, including the Discovery Request field.

In addition, the DMG beacon includes the Beamforming Feedback element. The Beamforming Feedback element includes fields to identify the element (e.g. Element ID, Length, Element ID Extension fields), a MAC address field that represents the MAC address of AP/PCP300, and SSW Feedback that contains beamforming feedback information Field.

The SSW Feedback field can also contain the same sub-fields as the SSW Feedback field of the 11ad specification. In addition, the description of the sub-columns can also refer to the description of FIG. 4. Therefore, the description here is omitted.

STA100 includes the Beamforming Feedback element in the DMG beacon with Discovery Mode=1. In this way, the STA 100 can notify the STA (for example, AP/PCP300) shown in the MAC address field of beamforming feedback information (for example, the content of the SSW Feedback field).

Fig. 44 is a diagram showing another example of the format of the DMG beacon. Figure 44 is different from Figure 43 in that the Discovery Request field is included in the SSW Feedback field of the Beamforming Feedback element. In this way, since the format of the SSW Feedback field is the same format as in FIG. 4, the AP/PCP300 receiving process becomes easier.

The AP/PCP300 receives the DMG beacon that contains the field (DR=1) and the best sector information indicating the discovery request in the DTI of Figure 42. In order to communicate with the STA100, it is based on the received best sector information , Set the transmitting antenna to the best sector.

AP/PCP300 sends a Probe response to STA100 in DTI. STA100 receives the Probe response and completes the discovery.

STA100 receives the DMG beacon from AP/PCP300 in BTI. When the BFT during A-BFT is not completed, it includes the information of the best sector in DTI and sends the field indicating the discovery request (DR=1) DMG beacons. In this way, the AP/PCP300 can obtain the best sector information in DTI, and can omit the transmission of the SSW frame and the reception of the SSW-FB frame (refer to Embodiment 3) and send the Probe response.

In this way, even when the STA 100 does not complete the BFT during the A-BFT period for the AP/PCP 300, it can still avoid the increase in the time required for discovery.

FIG. 45 is a flowchart showing an example of a procedure for the STA 100 to perform discovery. The same processing as in FIG. 7 (Embodiment 1) is assigned the same number, and the description is omitted.

First, STA100 starts to discover (S001). Next, the STA 100 receives the DMG beacon in the BTI (S002).

When the STA100 is not scheduled during the A-BFT period (S403: NO-1), in order to transmit the DMG beacon with Discovery Mode=1, it shifts to S421. The description of S421 will be described later. In addition, STA100, similar to Embodiment 1, may return to S002 in order to wait for the next BTI (refer to S403 in FIG. 45: NO-2 and DTI in FIG. 42).

Next, when the STA100 is scheduled during the A-BFT period (S403: YES), it transmits an SSW frame (S404). Furthermore, here, STA100 is different from the situation of S004 in FIG. 7 in that DR=1 is not set in the SSW frame (refer to the A-BFT period in FIG. 2).

When the AP/PCP 300 does not receive the SSW frame of S404 (S405: NO-1), the process returns to S002 (refer to the A-BFT period in Fig. 2). At this time, the SSW-FB frame (and the Probe response of S012) is not sent to STA100. Here, the case where the SSW frame is not received includes a case where a reception error occurs, or a case where the received power is lower than a predetermined value (predetermined value), etc. In addition, when the AP/PCP300 does not receive the SSW frame of S404 (S405: NO-2), the flow can also be transferred to S421 described later.

When the AP/PCP300 receives the SSW frame of S404 (S405: YES), it determines the best frame according to the SSW frame (S406). Then, the AP/PCP300 transmits the SSW-FB frame to the STA100 (S407) (refer to the A-BFT period in FIG. 2). Then, the flow proceeds to S408.

In S408, when the STA100 does not receive the SSW-FB frame from the AP/PCP300 (S408: NO), it transfers to S421 (refer to the A-BFT period in FIG. 2) in order to transmit the DMG beacon with Discovery Mode=1.

In S421, the STA100 changes the transmission sector for each DMG beacon to transmit the DMG beacon with Discovery Mode=1 (S421) (refer to DTI in FIG. 42). Furthermore, the STA100 transmits the DMG beacon with Discovery Mode=1 including the best sector information of the AP/PCP300 according to the received quality of the AP/PCP300 DMG beacon received in S002. In addition, the STA 100 includes the schedule information in the DMG beacon, and sets a different BTI, A-BFT period, and DTI from the schedule (time) set in the DMG beacon by the AP/PCP 300.

In addition, the AP/PCP300 receives the DMG beacon of S421, and stores the best sector information contained in the DMG beacon in the memory in order to communicate with the STA100 (S422). In this way, the BFT between STA100 and AP/PCP300 is completed (refer to DTI in FIG. 42). Then, AP/PCP300 skips the transmission of the SSW frame, and shifts to S435 (refer to DTI in FIG. 42). This point is different from the case of the third embodiment.

In S408, when the STA100 receives the SSW-FB frame from the AP/PCP300 (S408: YES), it stores the information of the best sector included in the SSW-FB frame in the memory (S431). Then, the STA100 judges that the initial BFT (success) between the AP/PCP300 and its own STA100 is completed (S432). The processing of S432 and S432 is the same as the processing of S009 and S010 in FIG. 7, respectively.

Then, the STA100 transmits the Probe request to the AP/PCP300 in DTI (S433).

In addition, when the AP/PCP300 receives the Probe request and there is no receiving error, it sends an ACK frame after SIFS (3msec) (S434). The processing of S434 is the same as the processing of S011 in FIG. 7. Then, the flow proceeds to S435.

In S435, AP/PCP300 sends Probe response to STA100 (S435). Furthermore, the AP/PCP300 can also measure the reception quality of the DMG beacon in S422 to determine the best sector of the STA100, and in S012, the information of the best sector of the STA100 can be included in the Probe response (refer to the DTI in FIG. 42).

In addition, STA100 receives the Probe response of S435, and after SIFS (3msec), sends an ACK frame to AP/PCP300 (S436).

Then, the STA100 stores the scan result contained in the Probe response of S436 in the memory (S437). The processing of S437 is the same as the processing of S015 in FIG. 7.

Then, STA100 completes the discovery of AP/PCP300 (S438). The processing of S438 is the same as the processing of S016 in FIG. 7.

(Modification of Embodiment 4) <Modification 4-1> As shown in Fig. 42, AP/PCP300 can also receive DMG beacon including the field (DR=1) indicating the discovery request in DTI, and use BTI to display The fields that can be responded to are included in the DMG beacon and sent.

<Modification 4-2> For multiple APs/PCPs (not shown), when the STA100 has obtained the best sector information, it is also possible to include multiple Beamforming Feedback elements in the DMG beacon in the DTI. According to the procedure described later, STA100 can shorten the delay in obtaining Probe responses related to multiple APs/PCPs, and complete active scanning as soon as possible.

<Modification 4-3> In DTI, the STA100 may include the element indicating the discovery criterion in the DMG beacon and transmit it (refer to Modification 3-2 of Embodiment 3).

<Modification 4-4> In DTI, STA100 may include a field or subfield indicating the category of the discovery request, and transmit it by including it in a DMG beacon (refer to Modification 1-2 of Embodiment 1, Figure 13) . In addition, AP/PCP300 can also send additional information corresponding to the category of the discovery request in DTI, which is included in the Probe response.

<Modification 4-5> Furthermore, the STA100 can also transmit a DMG beacon including a field or sub-field indicating the number of the TRN-R sub-field in DTI (refer to Fig. 14 and Fig. 15).

When AP/PCP300 receives a DMG beacon that contains a field that indicates a discovery request (DR=1), and contains a TRN-R subfield that indicates a field or subfield more than 1 digits, it can also be sent with DTI Probe response in TRN-R sub-field.

<Modification 4-6> In addition, PCP/AP300 can also be used in DTI, so that the information requested from STA100 for Probe response is included in the Probe response and sent (refer to Figure 30).

<Modification 4-7> PCP/AP300 can also send DMG beacons containing information about BSS (for example, DMG Capabilities of AP/PCP300 including information of Probe response, information required for STA100 to complete discovery) in DTI to Replace the Probe response in Figure 42.

FIG. 46 is a diagram showing an example of a procedure for the STA 100 to perform discovery.

In DTI, the PCP/AP300 transmits a DMG beacon containing information about the BSS to replace the DTI Probe response in FIG. 42. The DMG beacon may also contain all or part of the elements contained in the Probe response.

The STA100 obtains the discovery information used in the AP/PCP300 by receiving the DMG beacon sent by the AP/PCP300 due to the DTI, and completes the discovery.

In addition, other STAs not shown in the figure can also receive DMG beacons transmitted by AP/PCP300 in DTI, and omit the transmission of DMG beacons from AP/PCP300 in BTI to those performed by STA100 in DTI. The transmission of the DMG beacon completes the discovery.

AP/PCP300 can also be used in BTI, so that the transmitted DMG beacon does not contain all BSS-related information (or part of it), so that the DMG beacon transmitted in DTI contains all the BSS-related information.

Here, since the AP/PCP300 repeatedly transmits the DMG beacons of the BTI for each BI (that is, the number of transmissions is high), the consumption of many wireless resources can be suppressed by not including all the information about the BSS.

In addition, since the transmission of DMG beacons in DTI is performed when a DMG beacon with Discovery Mode=1 is received, unnecessary transmission of DMG beacons can be suppressed, and wireless resources can be used efficiently. For example, it is possible to avoid transmitting DMG beacons containing relevant BSSs when there is no STA performing discovery.

As above, STA100 is in BTI and receives DMG beacon from AP/PCP300. When the BFT during A-BFT is not completed, STA100 is in DTI, including the information of the best sector, and sends the field containing the request for discovery ( DR=1) DMG beacon. In this way, the AP/PCP300 can obtain the best sector information, and the transmission of the SSW frame and the reception of the SSW-FB frame during the A-BFT period (refer to Embodiment 3) can be omitted, and the Probe response can be transmitted in the DTI.

In this way, even when the STA 100 does not complete the BFT during the A-BFT period for the AP/PCP 300, it can still avoid the increase in the time required for discovery.

In addition, in DTI, when AP/PCP300 receives a DMG beacon containing a field (DR=1) indicating a discovery request, the transmission of the SSW frame of the DTI is omitted and a Probe response is transmitted. In this way, the increase in interference to other STAs (not shown) caused by the transmission of the SSW frame in the DTI can be avoided.

(Embodiment 5) In Embodiment 3, it is explained that STA100 is in BTI, and the field (DR=1) indicating the discovery request is transmitted in the DMG beacon of Discovery Mode=1, and AP/PCP300 is in the A-BFT period When BFT is completed, the procedure of sending Probe response to DTI. In this embodiment, the method for AP/PCP300 to include the shortened information of the BSS in the SSW frame and the Short SSW packet during the A-BFT period is described to replace the Probe response to shorten the discovery time of the STA100.

FIG. 47 is a diagram showing an example of a procedure of Embodiment 5 in which STA 100 performs active scanning for AP/PCP 300.

In DTI, STA100 transmits the field (DR=1) indicating the discovery request, which is included in the DMG beacon of Discovery Mode=1.

AP/PCP300 receives DMG beacons at DTI.

When AP/PCP300 receives a DMG beacon with Discovery Mode=1 that contains a field (DR=1) indicating a discovery request in BTI, it will include the shortened information about the BSS in the SSW frame and Short during A-BFT. SSW packet is sent. Furthermore, in Figure 47, AP/PCP300 transmits Short SSW packets.

FIG. 48 is a diagram showing an example of the format of a Short SSW packet including shortened information about BSS. Furthermore, descriptions of the same fields and sub-fields as in FIG. 23 are omitted.

The Short SSW packet contains a control tail, and the control tail contains, for example, a Reduced Discovery Information field (shortened discovery information field).

The Reduced Discovery Information field contains the information required by the STA100 to complete the discovery, such as BSS Type, Short SSID, RSN Info, and Reduced Capabilities fields (shortened capability fields).

The Reduced Capabilities field contains, for example, the information required by the STA100 for initial connection (Association, Authentication) after the discovery is completed. Contains, for example, authentication programs or security algorithms supported by AP/PCP300.

The Reduced Capabilities field includes, for example, the DMG Privacy field, ECAPC (Extended centralized access point or personal basic service set control point cluster) Policy field Bit.

The STA 100 receives the Short SSW packet containing shortened information about the BSS during the A-BFT period in FIG. 47.

The STA100 judges whether to send a Probe response based on the received shortened information about the BSS. For example, because the Reduced Capabilities field does not contain all the information about AP/PCP300, when the information about the functions used by the STA100 is not included in the Reduced Capabilities field, it is determined that the DTI sends a Probe response.

Also, for example, with regard to multiple optional functions of the AP/PCP300, although the Reduced Capabilities field contains bits to indicate whether the AP/PCP300 supports each optional function, it does not include parameters related to each optional function.

Therefore, STA100 uses the selection function supported by AP/PCP300. When the additional parameters related to the selection function are insufficient, it can also send a Probe request to AP/PCP300 in DTI.

STA100 can obtain additional parameters related to the selection function by receiving the Probe response from AP/PCP300.

Furthermore, when the STA100 does not use the selection function supported by the AP/PCP300, or when the selection function is used and the additional parameters related to the selection function are insufficient, it can also omit the probe request to the AP/PCP300. STA100 can also decide whether to send Probe request to AP/PCP300 according to the type of selection function used.

STA100 can also send SSW-FB frames to AP/PCP300 when receiving SSW frames and Short SSW packets during A-BFT.

Since AP/PCP300 receives a DMG beacon with Discovery Mode=1 in the field (DR=1) indicating the discovery request at BTI, it sends a Short SSW packet containing shortened information about the BSS during the A-BFT period, and then No Probe response is sent, so STA100 can shorten the delay required for discovery. In addition, since the AP/PCP300 does not transmit Probe responses, the interference to other STAs can be reduced.

In addition, since the STA 100 determines whether to transmit the Probe request in the DTI based on the shortened information about the BSS, unnecessary Probe request transmission can be deleted, the delay required for discovery is shortened, and the interference to other STAs is reduced.

FIG. 49 is a flowchart showing an example of a procedure for STA100 to perform discovery by active scanning with Discovery Mode=1. The same numbers are attached to the same processes as those in FIG. 36 of the third embodiment, and the description is omitted.

First, STA100 starts to discover (S301).

Next, the STA 100 transmits a DMG beacon with the value of the Discovery Mode field set to 1 in the BTI (S302).

When the AP/PCP 300 does not receive the DMG beacon of S302 in the BTI, or when there are other reasons (for example, when interference is detected) (S303: NO), the flow proceeds to S506, which will be described later. At this time, the AP/PCP300 omits the transmission of the Short SSW frame of S505 described later.

When the AP/PCP300 receives the DMG beacon of S302 in the BTI (S303: YES), the AP/PCP300 selects the best sector (S304). Then, the AP/PCP300 transmits the Short SSW packet to the STA100 during the A-BFT period (S505). Furthermore, the AP/PCP300 can also switch the transmission sector for each Short SSW packet to transmit the Short SSW packet. In addition, the AP/PCP300 transmits the Short SSW packet including the information of the best sector of the STA100 (measured by the DMG beacon of S303, for example). In addition, when the AP/PCP300 receives a DMG beacon containing a field (DR=1) indicating a discovery request at the BTI, it adds a control tail to the Short SSW packet and transmits it including shortened information about the BSS.

When the STA100 does not receive the Short SSW packet of S505 during the A-BFT period (S506: NO), the process returns to S302, and the STA100 may try to transmit the DMG beacon again. The situation where the Short SSW packet is not received here can also include: in S505, the AP/PCP300 did not transmit the Short SSW packet; and/or due to competition with other STAs or insufficient receiving sensitivity, STA100 failed Received Short SSW packet, etc. Furthermore, the STA 100 may also end the discovery of the wireless channel and AP/PCP 300 after a predetermined number of attempts have been made.

When STA100 receives a Short SSW packet during A-BFT (S506: YES), it selects the best sector of AP/PCP300, and stores the best sector information in the memory for future use in communication with AP/PCP300 . In addition, the STA 100 determines whether to send the Probe request according to the shortened information about the BSS included in the control tail of the Short SSW packet (S507). Furthermore, in S507, when the STA100 decides to omit the transmission requested by the Probe, the process can also proceed to S517 to complete the discovery.

STA100 sends the SSW-FB frame to AP/PCP300 (S508).

In addition, when the AP/PCP300 receives the SSW-FB frame of S508 (S509: YES), it stores the information of the best transmission sector included in the SSW-FB frame in the memory (S510). Furthermore, when the AP/PCP300 does not receive the SSW-FB frame of S508, the process can also return to S302 (S509: NO-1). In addition, at this time, the flow can also proceed to S517 to complete the discovery (S509: NO-2).

Next, the AP/PCP300 judges that the BFT between its own AP/PCP300 and the STA100 is completed (S511).

In addition, when the STA100 decides to transmit the Probe request in S507 (S512-1: NO), it transmits the Probe request to the AP/PCP300 (S512-2), and the flow proceeds to S513. Furthermore, when the STA 100 decides to omit the transmission requested by the Probe in S507, it does not perform the processing of S512-2 (S512-1: YES), the flow proceeds to S517, and the discovery is completed.

In addition, the AP/PCP300 receives the Probe request of S512, and after SIFS, sends the ACK frame to the STA (S513).

Then, the AP/PCP300 sends a Probe response to the STA100 (S514).

In addition, STA100 receives the Probe response of S514, and after SIFS, sends the ACK frame to AP/PCP300 (S515).

Then, the MAC processor of the STA100 (refer to FIG. 8) notifies the main controller of the scanning result (for example, the information and reception quality of the AP/PCP300 included in the Probe response) (S516).

Then, STA100 completes the discovery of AP/PCP300 (S517).

FIG. 50 is a block diagram showing an example of the configuration of the communication device (AP/PCP300 and STA100). The description of the same components as those in FIG. 32 is omitted.

The MAC processor includes a control tail message generating circuit and a control tail message processing circuit.

During the A-BFT period, the control tail message generating circuit of AP/PCP300 generates shortened information about BSS based on the information about BSS (for example, input from the main controller), generates the data of the control tail (refer to Figure 48), and inputs it to the PHY Transmission circuit. The PHY transmission circuit encodes and/or modulates the data at the control tail and attaches it to the Short SSW packet for transmission.

During the A-BFT period, the STA100 receives the Short SSW packet with the control tail attached, and the PHY receiving circuit demodulates and/or decodes the body of the Short SSW packet and the control tail to generate the Short SSW data and the control tail data, and input them to the MAC processor. The control tail message processing circuit generates shortened information about the BSS from the control tail data, and outputs it to the host.

If the message generation circuit determines the transmission of the Probe response based on the received shortened information about the BSS, it generates the data requested by the Probe and inputs it to the PHY transmission circuit.

The HOST (host) will receive the shortened information about the BSS and the probe response information (Probe request) as the discovery result.

(Variation of Embodiment 5) <Variation 5-1> In BTI, STA100 can also add a field indicating whether or not to support the reception of Short SSW packets to the DMG beacon, where the aforementioned Short SSW packet is attached with the relevant BSS To shorten the control tail of the information.

<Modification 5-2> During the A-BFT period of the AP/PCP300, the information included in the control tail can also be the discovery information formulated in FILS (First Initial Link Setup Specification, IEEE802.11ai).

<Modification 5-3> In the A-BFT period, the STA100 may be transmitted by including the field containing the discovery request (DR=1) in the SSW-FB frame, similarly to FIG. 35. When the STA100 judges that it is necessary to send the Probe request, it can also send the field containing the discovery request (DR=1) in the SSW-FB frame.

When AP/PCP300 receives the SSW-FB frame containing the field (DR=1) containing the discovery request, it sends the Probe response to STA100 in DTI.

When STA100 judges to send the Probe request, it can also include the field containing the discovery request (DR=1) in the SSW-FB frame and send it during A-BFT, instead of sending the Probe request, thereby receiving from the AP /PCP300's Probe responds.

<Modification 5-4> The STA100 can also determine that the AP/PCP300 is not the target of discovery based on the shortened information about the BSS received during the A-BFT period, and interrupt the transmission of the Probe request. For example, the BSS Type is not suitable for the BSS Type corresponding to the application software used by the STA100.

As above, when AP/PCP300 receives a DMG beacon containing Discovery Mode=1 in the field (DR=1) indicating the discovery request in BTI, AP/PCP300 sends a Short SSW packet containing shortened information about the BSS, omitted Transmission of Probe response. In this way, the STA100 can shorten the delay required for discovery. In addition, since the AP/PCP300 omits the transmission of the Probe response, the interference to other STAs can be reduced.

In addition, the STA 100 determines whether to send the Probe request based on the shortened information about the BSS received during the A-BFT period. In this way, unnecessary transmissions required by Probe can be deleted, the delay required for discovery can be shortened, and the interference to other STAs can be reduced.

(Embodiment 6) When AP/PCP300 receives an SSW frame containing DR=1 during A-BFT, in Embodiment 1, it will send a Probe response, but in Embodiment 6, additional control is added to the SSW-FB frame The tail (same as the control tail of Short SSW added to Embodiment 5) is transmitted so that the discovery of STA100 is completed as soon as possible.

FIG. 51 is a diagram showing an example of a procedure for the STA 100 to perform active scanning.

In BTI, AP/PCP300 switches the transmission sector for each DMG beacon and transmits DMG beacons.

STA100 receives the DMG beacon at BTI and determines the best sector for AP/PCP300.

During the A-BFT, STA100 transmits the information of the best sector of AP/PCP300 and the SSW frame containing the field (DR=1) indicating the discovery request.

AP/PCP300 receives the SSW frame and determines the best sector for STA100.

During the A-BFT period, AP/PCP300 makes the SSW-FB frame contain the information of the best sector of STA100, and sends it with a control tail. The control tail contains shortened information about the BSS (refer to Figure 48).

During the A-BFT period, the STA100 receives the SSW-FB frame with the control tail attached. The control tail will be demodulated and/or decoded to obtain shortened information about the BSS.

STA100 decides whether to request the information from the Probe response from AP/PCP300 based on the shortened information about the BSS. In short, decide whether to send the Probe request frame.

When STA100 receives the DMG beacon from AP/PCP300 at BTI, it uses the SSW-FB frame to obtain the shortened information about the BSS before performing Probe exchange (the transmission of the Probe request frame and the reception of the Probe response). Whether AP/PCP300 is the AP/PCP to be discovered. Therefore, since unnecessary Probe exchanges are not performed, the delay required for discovery can be shortened, and interference with other STAs (not shown) can be suppressed.

Furthermore, the STA100 can also transmit SSW frames during the A-BFT period without DR=1. AP/PCP300 can also transmit SSW-FB frame with control tail during A-BFT regardless of whether the received SSW frame contains DR=1.

The STA (STA100) that supports the reception of the control tail will control the demodulation and/or decoding of the tail, and obtain the shortened information about the BSS. An STA (not shown) that does not support the reception of the control tail receives the SSW-FB frame and discards the control tail.

Furthermore, the STA100 can also send Short SSW packets to replace the SSW frame during the A-BFT period. When AP/PCP300 receives an SSW frame containing DR=1 and a Short SSW packet, it determines that the transmission source STA (such as STA100) supports the reception of the control tail, and adds the control tail to the SSW-FB frame and transmits it. When AP/PCP300 receives an SSW frame that does not contain DR=1, it can also determine that the source STA (such as other STAs not shown) does not support the reception of the control tail, and transmits without adding a control tail to the SSW-FB frame.

Based on the above, the backward compatibility with 11ad specifications can be maintained.

FIG. 52 is a flowchart showing an example of a procedure for the STA 100 to perform discovery. In some cases, the same processing as in FIG. 7 (Embodiment 1) is given the same number, and the description is omitted.

First, STA100 starts discovery (S001), and executes the same processing as S002 to S004 in FIG. 7.

When the AP/PCP300 receives the SSW frame (S005: YES) that contains the field (DR=1) indicating the discovery request, it sends the SSW-FB frame with the control tail attached to the STA100 (S607) (refer to Figure 51 During A-BFT). Furthermore, the AP/PCP300 can also use the best sector notified by the SSW frame to transmit the SSW-FB frame. In addition, AP/PCP300 can also transmit the best sector information of STA100 included in the SSW-FB frame.

In addition, when STA100 receives the SSW-FB frame of S607 (S608: YES), it prepares to communicate with AP/PCP300, and stores the information of the best sector contained in the SSW-FB frame in the memory (refer to Figure 51). During A-BFT). In addition, when the STA 100 receives the SSW-FB frame including the control tail, it decides whether to send the Probe request (S609) based on the shortened information about the BSS contained in the control tail (refer to the A-BFT period in FIG. 51).

Then, the STA 100 judges that the initial BFT (success) between the AP/PCP 300 and its own STA 100 is completed (S610).

Then, when the STA 100 decides to transmit the Probe request in S609 (S611-1: NO), it transmits the Probe request to the AP/PCP 300 in DTI (S611-2) (refer to DTI in FIG. 2), and the flow proceeds to S612. Furthermore, when the STA100 decides not to transmit the Probe request in S609 (S611-1: YES), the flow can also proceed to S616 to complete the discovery of AP/PCP300 (refer to DTI in FIG. 51).

In addition, the AP/PCP300 receives the Probe request of S612 in DTI, and after SIFS, transmits the ACK frame to STA100 (S612) (refer to DTI in FIG. 2).

Then, AP/PCP300 sends Probe response to STA100 in DTI (S613).

In addition, STA100 receives the Probe response of S613 in DTI, and after SIFS, transmits the ACK frame to AP/PCP300 (S614).

Then, the STA100 stores the scan result included in the Probe response in the memory (S615).

Then, STA100 completes the discovery of AP/PCP300 (S616). Furthermore, in order to discover other APs/PCPs (not shown), the STA 100 can also use the same wireless channel or switch the wireless channel, and return to S001 to repeat the discovery.

(Modification of Embodiment 6) AP/PCP300 can also add a control tail to indicate whether it supports the transmission of SSW-FB frames containing shortened information about BSS (refer to the A-BFT period in Fig. 51). The information is included in The DMG beacon (refer to BTI in FIG. 51) is transmitted.

Furthermore, during the A-BFT period in FIG. 51, STA100 can also include DR=1 in the SSW frame.

During the A-BFT period in FIG. 51, the STA100 can also include the field indicating the request of the Probe response of Embodiment 1 in the SSW frame. In addition, the STA100 can also include any one of the Probe response of the first embodiment, the shortened information about the BSS included in the control tail of the sixth embodiment, or the field that indicates that neither is requested, in the SSW frame. .

Furthermore, during the A-BFT period in FIG. 51, the STA 100 can also send Short SSW packets to replace the SSW frame.

The AP/PCP300 includes the information in the control tail in the SSW-FB frame during the A-BFT period in Fig. 51. It can also be the discovery information formulated in FILS (First Initial Link Setup Specification, IEEE802.11ai) as in Embodiment 5. .

STA100 can also determine that the AP/PCP300 is not an object of discovery based on the shortened information about the BSS received during the A-BFT period, and interrupt the transmission of the Probe request. For example, the BSS Type is not suitable for the BSS Type corresponding to the application software used by the STA100.

As above, when AP/PCP300 receives an SSW frame containing a field (DR=1) indicating a discovery request during A-BFT, it will send an SSW-FB frame with a control tail containing shortened information about the BSS attached. . In this way, the STA100 can obtain the shortened information about the BSS before the Probe exchange, and determine whether the AP/PCP300 is the AP/PCP to be discovered. Therefore, since unnecessary Probe exchanges are not performed, the delay required for discovery can be shortened, and interference to other STAs (not shown) can be suppressed.

The embodiment has been described above.

The functional blocks used in the description of the above embodiments are typically realized as integrated circuit LSIs. These single-chips may be made individually, or a part or all of them may be included and made into a single-chip. Although LSI is used here, it is sometimes called IC, system LSI, Super LSI, or Ultra LSI depending on the degree of integration.

In addition, the method of integrated circuitization is not limited to LSI, and it can also be realized by a dedicated circuit or a general-purpose processor. It is also possible to use a programmable FPGA (Field Programmable Gate Array) after LSI manufacture, or a reconfigurable processor (configurable processor).

In addition, if there is a technology that can replace LSI's integrated circuit due to advances in semiconductor technology or other derived technologies, of course, this technology can also be used to integrate functional blocks. As a possibility, the application of biotechnology can be considered.

This patent application is based on the U.S. Patent Application No. 62/430,251 filed on December 5, 2016 to claim its priority. This application quotes the entire content of the U.S. Patent Application No. 62/430,251.

Industrial Applicability The aspect of this disclosure is suitable for complying with future Wi-Fi specifications, such as the communication system of IEEE802.11ay specifications.

100、200‧‧‧STA300‧‧‧AP/PCP1001‧‧‧Antenna array A-BFT‧‧‧Link beamforming training AP/PCP‧‧‧Access point/Personal basic service point BFT‧‧‧Beamforming training BI ‧‧‧Beacon interval BSS‧‧‧Basic service set BTI‧‧‧CRC during beacon transmission‧‧‧Cyclic redundancy check DBcn‧‧‧DMC beacon DMG‧‧‧Directivity number is more than gigabit DRS‧ ‧‧It was found that it is required to support DTI‧‧‧Data transmission interval FCS‧‧‧Frame check sequence L-CEF‧‧‧Transmission channel estimation field L-STF‧‧‧Traditional short training field MAC‧‧‧Media access Control PHY‧‧‧Physical layer RA‧‧‧Receiving address S001～S016, S101～109, S201～214, S301～S316, S403～S408, S421, S422, S431～S438, S505～S511, S512-1, S512-2, S513～S517, S607～S610, S611-1, S611-2, S612～S616‧‧‧Step SSW‧‧‧Sector scan STA‧‧‧Workstation TA‧‧‧Transmit address

Fig. 1 is a block diagram showing an example of an STA performing active scanning and discovering other STAs. Fig. 2 is a diagram showing an example of a procedure for an STA to perform active scanning. Fig. 3 is a diagram for explaining the procedure for the STA to perform active scanning in the first embodiment. FIG. 4 is a diagram showing an example of the format of an SSW frame including a field (DR=1) indicating a discovery request. FIG. 5 is a diagram showing an example of the format of a Probe response transmitted by AP/PCP in DTI. FIG. 6 is a diagram showing an example of a procedure for the STA to perform active scanning at the same BI (beacon interval) that the STA performs active scanning. Fig. 7 is a flowchart showing an example of a procedure for STA to discover AP/PCP. Fig. 8 is a block diagram showing an example of the configuration of a communication device. Fig. 9 is a detailed block diagram showing an example of the configuration of the MAC processor. Fig. 10 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 11 is a diagram showing an example of the format of a DMG beacon. Fig. 12 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 13 is a diagram showing an example of the format of an SSW frame. Fig. 14 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 15 is a diagram showing an example of the format of an SSW frame. Fig. 16 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 17 is a diagram showing an example of the format of an SSW frame. Fig. 18 is a diagram showing another example of the format of the SSW frame. Fig. 19 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. FIG. 20 is a diagram showing an example of a procedure for STA to actively scan for AP/PCP. FIG. 21 is a diagram showing an example of the format of a Short SSW (Short SSW) packet. Fig. 22 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 23 is a diagram showing an example of the format of a Short SSW packet. FIG. 24 is a diagram showing an example of a procedure for STA to actively scan for AP/PCP. Fig. 25 is a diagram showing an example of the format of the SSW-FB frame. Fig. 26 is a diagram showing an example of a procedure for STA to actively scan for AP/PCP. Fig. 27 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 28 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. FIG. 29 is a diagram showing an example of the format of Probe response. Fig. 30 is a diagram showing an example of a procedure for STA to actively scan for AP/PCP. Fig. 31 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 32 is a block diagram showing an example of the configuration of a communication device (AP/PCP and STA). Fig. 33A is a diagram showing an example of a procedure for an STA to perform active scanning for AP/PCP in accordance with the second embodiment. FIG. 33B is a diagram showing an example of a procedure for the STA to actively scan for AP/PCP. Fig. 34 is a flowchart showing an example of a procedure for the STA to perform discovery. FIG. 35 is a diagram showing an example of a procedure for an STA to perform active scanning for AP/PCP in the third embodiment. FIG. 36 is a flowchart showing an example of a procedure for STA to perform discovery by active scanning with Discovery Mode=1. Fig. 37 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. FIG. 38 is a diagram showing an example of a procedure for STA to actively scan for AP/PCP. Fig. 39 is a diagram showing an example of the format of a DMG beacon. FIG. 40 is a diagram showing an example of a procedure for STA to actively scan for AP/PCP. Fig. 41 is a diagram showing an example of a procedure for an STA to actively scan for AP/PCP. Fig. 42 is a diagram showing an example of a procedure for an STA to perform active scanning for AP/PCP in accordance with the fourth embodiment. Fig. 43 is a diagram showing an example of the format of a DMG beacon. Fig. 44 is a diagram showing another example of the format of the DMG beacon. FIG. 45 is a flowchart showing an example of a procedure for the STA to perform discovery. Fig. 46 is a diagram showing an example of a procedure for the STA to perform discovery. Fig. 47 is a diagram showing an example of a procedure for an STA to perform active scanning for AP/PCP in accordance with the fifth embodiment. FIG. 48 is a diagram showing an example of the format of a Short SSW packet including shortened information about BSS. FIG. 49 is a flowchart showing an example of a procedure for STA to perform discovery by active scanning with Discovery Mode=1. Fig. 50 is a block diagram showing an example of the configuration of a communication device (AP/PCP and STA). FIG. 51 is a diagram showing an example of a procedure for an STA to perform active scanning. Fig. 52 is a flowchart showing an example of a procedure for the STA to perform discovery.

100‧‧‧STA

300‧‧‧AP/PCP

Claims (6)

A wireless communication method, which is a wireless communication method of a wireless communication device, includes: transmitting more than one beacon frame during the beacon transmission period; during the beamforming training period after the beacon transmission period, from other wireless communication The device receives more than one transmission sector scan frame; when the aforementioned one or more transmission sector scan frames contain information about the discovery request, scan the frame from the aforementioned one or more transmission sectors to retrieve the relevant information The information of the first transmission sector selected by the aforementioned other wireless communication device; scan the frame from more than one transmission sector included in the aforementioned received transmission sector, and select the first transmission sector used by the aforementioned other wireless communication device 2 Transmitting sector; during the aforementioned beamforming training period, using the aforementioned first transmitting sector to transmit a feedback frame containing information about the aforementioned selected second transmitting sector; and data after the aforementioned beamforming training period During the transmission, the first transmission sector is used to transmit a detection response frame containing information about the selected second transmission sector. For example, the wireless communication method of claim 1, wherein the wireless communication device changes the transmission sector for transmitting each beacon frame for each beacon frame. Such as the wireless communication method of claim 1, wherein the aforementioned wireless communication device is based on the aforementioned selected first transmission The sector information is used to determine the transmission destination of the aforementioned feedback frame to other wireless communication devices. For example, the wireless communication method of claim 3, wherein the first transmission sector is selected according to the reception quality of the beacon frames of the other wireless communication devices. Such as the wireless communication method of claim 1, wherein the second transmission sector is selected according to the reception quality of the scanning frame of the transmission sector of the wireless communication device. A wireless communication device having a transmitting circuit, a receiving circuit, and a MAC processing circuit. The transmitting circuit transmits more than one beacon frame during the beacon transmission period, and during the beamforming training period after the beacon transmission period , Use the second transmission sector to transmit more than one feedback frame, and use the second transmission sector to transmit the detection response frame during the data transmission period after the beamforming training period; the aforementioned receiving circuit is in the aforementioned beam During the shaping training period, it receives more than one transmission sector scan frame from other wireless communication devices; the aforementioned MAC processing circuit, when the aforementioned received more than one transmission sector scan frame contains information about the discovery request, Retrieve the scan frame of more than one transmission sector included in the aforementioned received transmission sector, and related to the first transmission sector selected by the aforementioned other wireless communication devices Scan the frame from more than one transmission sector that is included in the aforementioned received transmission sector, and is the transmission sector used by the aforementioned other wireless communication devices, select the second transmission sector, and generate information about the aforementioned selected transmission sector. 2 The feedback frame for the information of the transmission sector, and the detection response frame containing the information about the second transmission sector that has been selected above.

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