Patent Description:
Communication systems such as wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (such as, time, frequency, and power). A wireless network, for example a wireless local area network (WLAN), such as a Wi-Fi (institute of electrical and electronics engineers (IEEE) <NUM>) network may include an access point (AP) that may communicate with one or more stations (STAs) or mobile devices. The WLAN enables a user to wirelessly access an internet based on radio frequency technology in a home, an office, or a specific service area using a portable terminal such as a personal digital assistant (PDA), a laptop computer, a portable multimedia player (PMP), a smartphone, etc. The AP may be coupled to a network, such as the internet, and may enable a mobile device to communicate via the network (or communicate with other devices coupled to the AP). A wireless device may communicate with a network device bidirectionally. For example, in a WLAN, a STA may communicate with an associated AP via downlink and uplink. The downlink may refer to a communication link from the AP to the STA, and the uplink may refer to a communication link from the STA to the AP.

In recent times, to support increased numbers of devices supporting WLAN, such as smartphones, more APs have been deployed. Despite increase in use of WLAN devices supporting the IEEE <NUM>. 11ax high efficiency (HE) WLAN standard, that provide high performance relative to WLAN devices supporting the legacy IEEE <NUM>/n/ac standard, a WLAN system supporting higher performance is required due to WLAN users' increased use of high volume content such as a ultra-high definition video. Although a conventional WLAN system has aimed at increase of bandwidth and improvement of a peak transmission rate, actual users thereof could not feel drastic increase of such performance.

IEEE <NUM>. 11ax HE WLAN supports a bandwidth (BW) up to <NUM> and supports preamble puncturing for orthogonal frequency division multiple access (OFDMA) transmission. In order to achieve significant throughput improvement over IEEE <NUM>. 11ax HE WLAN, IEEE <NUM>. 11be extremely high throughput (EHT) WLAN extends maximum BW support from <NUM> to <NUM> and extends preamble puncturing support from OFDMA transmission only to both OFDMA transmission and non-OFDMA transmission. In addition, it is expected that HE STAs will exist with EHT STAs in a same EHT basic service set (BSS).

In IEEE <NUM>. 11ax HE WLAN, a multi-user ready-to-send (MU-RTS) trigger/clear-to-send (CTS) frame exchange procedure allows an AP to initiate a transmit opportunity (TXOP) and protect TXOP frame exchanges. However, it is unclear how to utilize the MU-RTS trigger/CTS frame exchange procedure for TXOP protection in IEEE <NUM>. 11be EHT WLAN in an efficient manner.

Therefore, there is a need for an access point (AP), a station (STA), and a wireless communication method, which can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability. <CIT>, which is published after the filing date and claims the priority date of <NUM>. <NUM>, relates to a method to enable a wireless access point to efficiently perform an operation of transmitting or receiving a frame requiring low latency time. <CIT> relates to a method and device for transmitting a physical layer protocol data unit (PPDU) in a transmission opportunity (TXOP). <NPL>, <NPL>) discusses EHT RTS and CTS procedure. <NPL>; <NPL>) relates to 11ax D4. <NUM> MAC comment resolution for MU-RTS/CTS.

An object of the present disclosure is to propose an access point (AP), and a wireless communication method, which can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability.

In a first aspect of the present disclosure, a wireless communication method is set out in claim <NUM>. Additional features are set out in claims <NUM> to <NUM>.

In an aspect of the present disclosure, an access point (AP) is provided as set out in claim <NUM>.

In order to illustrate the embodiments of the present disclosure or related art more clearly, the following figures will be described.

<FIG> illustrates an example of a wireless communications system according to the present disclosure. The wireless communications system may be an example of a wireless local area network (WLAN) <NUM> (also known as a Wi-Fi network) (such as next generation, next big thing (NBT), ultra-high throughput (UHT) or EHT Wi-Fi network) configured in accordance with various aspects of the present disclosure. As described herein, the terms next generation, NBT, UHT, and EHT may be considered synonymous and may each correspond to a Wi-Fi network supporting a high volume of space-time-streams. The WLAN <NUM> may include an AP <NUM> and multiple associated STAs <NUM>, which may represent devices such as mobile stations, personal digital assistant (PDAs), other handheld devices, netbooks, notebook computers, tablet computers, laptops, display devices (such as TVs, computer monitors, etc.), printers, etc. The AP <NUM> and the associated stations <NUM> may represent a basic service set (BSS) or an extended service set (ESS). The various STAs <NUM> in the network can communicate with one another through the AP <NUM>. Also illustrated is a coverage area <NUM> of the AP <NUM>, which may represent a basic service area (BSA) of the WLAN <NUM>. An extended network station (not shown) associated with the WLAN <NUM> may be connected to a wired or wireless distribution system that may allow multiple APs <NUM> to be connected in an ESS.

In some embodiments, a STA <NUM> may be located in the intersection of more than one coverage area <NUM> and may associate with more than one AP <NUM>. A single AP <NUM> and an associated set of STAs <NUM> may be referred to as a BSS. An ESS is a set of connected BSSs. A distribution system (not shown) may be used to connect APs <NUM> in an ESS. In some cases, the coverage area <NUM> of an AP <NUM> may be divided into sectors (also not shown). The WLAN <NUM> may include APs <NUM> of different types (such as a metropolitan area, home network, etc.), with varying and overlapping coverage areas <NUM>. Two STAs <NUM> also may communicate directly via a direct wireless link <NUM> regardless of whether both STAs <NUM> are in the same coverage area <NUM>. Examples of direct wireless links <NUM> may include Wi-Fi direct connections, Wi-Fi tunneled direct link setup (TDLS) links, and other group connections. STAs <NUM> and APs <NUM> may communicate according to WLAN radio and baseband protocol for physical and media access control (MAC) layers from IEEE <NUM> and versions including, but not limited to, <NUM>. 11b, <NUM>, <NUM>. 11a, <NUM>. 11n, <NUM>. 11ac, <NUM>. 11ad, <NUM>. 11ah, <NUM>. 11ax, <NUM>. 11ay, etc. In some other implementations, peer-to-peer connections or ad hoc networks may be implemented within the WLAN <NUM>.

<FIG> illustrates an example of a wireless communications system according to the present disclosure. The wireless communications system <NUM> may be an example of a next generation or EHT Wi-Fi system and may include an AP <NUM>-a and STAs <NUM>-a and <NUM>-b, and a coverage area <NUM>-a, which may be examples of components described with respect to <FIG>. The AP <NUM>-a may transmit a trigger frame <NUM> including a resource unit (RU) allocation table indication <NUM> on the downlink <NUM> to the STAs <NUM>.

In some implementations, a wireless communications system <NUM> may be a next generation Wi-Fi system (such as, an EHT system). In some implementations, wireless communications system <NUM> may also support multiple communications systems. For instance, wireless communications system <NUM> may support EHT communications and HE communications. In some implementations, the STA <NUM>-a and the STA <NUM>-b may be different types of STAs. For example, the STA <NUM>-a may be an example of an EHT STA, while the STA <NUM>-b may be an example of an HE STA. The STA <NUM>-b may be referred to as a legacy STA.

In some instances, EHT communications may support a larger bandwidth than legacy communications. For instance, EHT communications may occur over an available bandwidth of <NUM>, whereas legacy communications may occur over an available bandwidth of <NUM>. Additionally, EHT communications may support higher modulations than legacy communications. For instance, EHT communications may support <NUM> quadrature amplitude modulation (QAM), whereas legacy communications may support <NUM> QAM. EHT communications may support a larger number of spatial streams (such as, space-time-streams) than legacy systems. In one non-limiting illustrative example, EHT communications may support <NUM> spatial streams, whereas legacy communications may support <NUM> spatial streams. In some cases, EHT communications may occur a <NUM> channel, a <NUM> channel, or a <NUM> channel in unlicensed spectrum.

In some implementations, AP <NUM>-a may transmit a trigger frame <NUM> to one or more STAs <NUM> (such as, STA <NUM>-a and STA <NUM>-b). In some implementations, the trigger frame may solicit an uplink transmission from the STAs <NUM>. However, the trigger frame <NUM> may be received by an EHT STA <NUM>-a and HE STA <NUM>-b. The trigger frame <NUM> may be configured to solicit an uplink transmission from only HE STAs <NUM>-b. In some implementations, trigger frame <NUM> may be configured to solicit an uplink transmission from EHT STAs <NUM>-a. In some other implementations, the trigger frame <NUM> may be configured to solicit an uplink transmission from one or more EHT STAs <NUM>-a and one or more HE STAs <NUM>-b.

<FIG> illustrates an example of a wireless communications system according to the present disclosure. The wireless communications system <NUM> may be an example of a post-EHT Wi-Fi system and may include an AP <NUM>-b. AP <NUM>-b may be an example of a post-EHT AP <NUM>. The wireless communications system <NUM> may include HE STA <NUM>-c, EHT STA <NUM>-d, and post-EHT STA <NUM>-e, and a coverage area <NUM>-b, which may be examples of components described with respect to <FIG>. The AP <NUM>-b may transmit a trigger frame <NUM> including an RU allocation table indication <NUM> on the downlink <NUM> to the STAs <NUM>. In some implementations, STAs <NUM> may be referred to as clients.

In some implementations, an EHT AP <NUM> may serve both HE STAs <NUM> and EHT STAs <NUM>. The EHT AP <NUM> may send a trigger frame that may trigger a response from HE STAs <NUM> only, from EHT STAs <NUM> only, or from both HE STAs <NUM> and EHT STAs <NUM>. STAs <NUM> that are scheduled in the trigger frame may respond with trigger-based PPDUs. In some implementations, an EHT AP <NUM> may trigger HE STAs <NUM> (and not EHT STAs <NUM>) by sending an HE trigger frame format. In some implementations, an EHT AP <NUM> may trigger EHT STAs <NUM> (and not EHT STAs <NUM>) by sending an HE trigger frame format or an HE trigger frame format including some field or bit allocation adjustments. In some implementations, an EHT AP <NUM> may trigger EHT STAs <NUM> and HE STAs <NUM> by sending an HE trigger frame format including some field or bit allocation adjustments.

The trigger frame <NUM> may solicit a response from one or more EHT STAs <NUM> or one or more HE STAs <NUM>, or both. In some implementations, STAs <NUM> may not transmit unsolicited uplink transmissions in response to trigger frame <NUM>. In some implementations, trigger frame <NUM> may solicit an uplink orthogonal frequency division multiple access (OFDMA) transmission or an OFDMA with multi-user multiple-input multiple-output (MU-MIMO) transmission.

<FIG> illustrates one or more stations (STAs) <NUM> and an access point (AP) <NUM> of communication in a wireless communications system <NUM> according to the present disclosure. <FIG> illustrates that, the wireless communications system <NUM> includes an access point (AP) <NUM> and one or more stations (STAs) <NUM>. The AP <NUM> may include a memory <NUM>, a transceiver <NUM>, and a processor <NUM> coupled to the memory <NUM> and the transceiver <NUM>. The one or more STAs <NUM> may include a memory <NUM>, a transceiver <NUM>, and a processor <NUM> coupled to the memory <NUM> and the transceiver <NUM>. The processor <NUM> or <NUM> may be configured to implement proposed functions, procedures and/or methods described in this description. Layers of radio interface protocol may be implemented in the processor <NUM> or <NUM>. The memory <NUM> or <NUM> is operatively coupled with the processor <NUM> or <NUM> and stores a variety of information to operate the processor <NUM> or <NUM>. The transceiver <NUM> or <NUM> is operatively coupled with the processor <NUM> or <NUM>, and the transceiver <NUM> or <NUM> transmits and/or receives a radio signal.

In some embodiments, the processor <NUM> is configured to control the transceiver <NUM> to transmit a multi-user ready-to-send (MU-RTS) trigger frame to a plurality of stations (STAs) <NUM>, wherein the MU-RTS trigger frame indicates whether a clear-to-send (CTS) frame response is to be transmitted by each of the plurality of STAs <NUM> on a primary <NUM> channel (P20), a primary <NUM> channel (P40), a primary <NUM> channel (P80), a primary <NUM> channel (P160), or a <NUM> channel, and at least one <NUM> channel is punctured in the P80, the P160, or the <NUM> channel. This can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability.

In some embodiments, the processor <NUM> is configured to control the transceiver <NUM> to receive a multi-user ready-to-send (MU-RTS) trigger frame from an access point (AP) <NUM>, wherein the MU-RTS trigger frame indicates whether a clear-to-send (CTS) frame response is to be transmitted by the transceiver <NUM> on a primary <NUM> channel (P20), a primary <NUM> channel (P40), a primary <NUM> channel (P80), a primary <NUM> channel (P160), or a <NUM> channel, and at least one <NUM> channel is punctured in the P80, the P160, or the <NUM> channel. This can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability.

<FIG> illustrates a wireless communication method <NUM> performed by an AP according to an embodiment of the present disclosure. In some embodiments, the method <NUM> includes: a block <NUM>, transmitting, by an access point (AP), a multi-user ready-to-send (MU-RTS) trigger frame to a plurality of stations (STAs), wherein the MU-RTS trigger frame indicates whether a clear-to-send (CTS) frame response is to be transmitted by each of the plurality of STAs on a primary <NUM> channel (P20), a primary <NUM> channel (P40), a primary <NUM> channel (P80), a primary <NUM> channel (P160), or a <NUM> channel, and at least one <NUM> channel is punctured in the P80, the P160, or the <NUM> channel. This can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability.

<FIG> illustrates a wireless communication method <NUM> performed by a STA according to the present disclosure. In some embodiments, the method <NUM> includes: a block <NUM>, receiving, by a station (STA) of a plurality of STAs, a multi-user ready-to-send (MU-RTS) trigger frame from an access point (AP), wherein the MU-RTS trigger frame indicates whether a clear-to-send (CTS) frame response is to be transmitted by each of the plurality of STAs on a primary <NUM> channel (P20), a primary <NUM> channel (P40), a primary <NUM> channel (P80), a primary <NUM> channel (P160), or a <NUM> channel, and at least one <NUM> channel is punctured in the P80, the P160, or the <NUM> channel. This can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability.

In some embodiments, the P80, the P160 or the <NUM> channel in which the at least one <NUM> channel is punctured comprises one <NUM>+<NUM> tone multiple resource unit (MRU), one <NUM>+<NUM> tone MRU, one <NUM>+<NUM>+<NUM> tone MRU, one 2x996+<NUM> tone MRU, one 3x996 tone MRU, or one 3x996+<NUM> tone MRU. In some embodiments, the one <NUM>+<NUM> tone MRU results from puncturing any non-primary <NUM> channel from the P80, the one <NUM>+<NUM> tone MRU results from puncturing any non-primary <NUM> channel from the P160, the one <NUM>+<NUM>+<NUM> tone MRU results from puncturing any non-primary <NUM> channel from the P160, the one 2x996+<NUM> tone MRU results from puncturing any non-primary <NUM> channel from any consecutive <NUM> portion of the <NUM> channel, the one 3x996 tone MRU results from puncturing any non-primary <NUM> channel from the <NUM> channel, or the one 3x996+<NUM> tone MRU results from puncturing any non-primary <NUM> channel from the <NUM> channel. In some embodiments, each user information field of the MU-RTS trigger frame comprises a subfield and an RU allocation subfield, and the subfield and the RU allocation subfield of each user information field in the MU-RTS trigger frame indicate RU allocation information. In some embodiments, the subfield of each user information field in the MU-RTS trigger frame comprises a lower/upper <NUM> segment subfield.

In some embodiments, the subfield of each user information field in the MU-RTS trigger frame is set to a first value if the P80, the P160 or the <NUM> channel in which the at least one <NUM> channel is punctured comprises the one <NUM>+<NUM> tone MRU, the one <NUM>+<NUM> tone MRU, or the one <NUM>+<NUM>+<NUM> tone MRU. In some embodiments, the subfield of each user information field in the MU-RTS trigger frame is set to the first value if the P80, the P160 or the <NUM> channel in which the at least one <NUM> channel is punctured comprises the one 2x996+<NUM> tone MRU, the one 3x996 tone MRU, or the one 3x996+<NUM> tone RU and the at least one <NUM> channel is punctured from a lowest frequency <NUM> channel of the <NUM> channel. In some embodiments, the subfield of each user information field in the MU-RTS trigger frame is set to a second value if the P80, the P160 or the <NUM> channel in which the at least one <NUM> channel is punctured comprises the one 2x996+<NUM> tone MRU, the one 3x996 tone MRU, or the one 3x996+<NUM> tone RU and the at least one <NUM> channel is punctured from a second lowest frequency <NUM> channel of the <NUM> channel.

In some embodiments, the RU allocation subfield of each user information field in the MU-RTS trigger frame is set to indicate the one <NUM>+<NUM> tone MRU as at least one of the followings: a first bit is set to <NUM> if a non-primary <NUM> channel is punctured from the P80 which is only an <NUM> channel or a lowest frequency <NUM> channel of the P160; the first bit is set to <NUM> if the non-primary <NUM> channel is punctured from the P80 which is a second lowest frequency <NUM> channel of the P160; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of the P80; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of the P80; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a third lowest frequency <NUM> channel of the P80; or the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a fourth lowest frequency <NUM> channel of the P80.

In some embodiments, the RU allocation subfield of each user information field in the MU-RTS trigger frame is set to indicate the one <NUM>+<NUM> tone MRU as at least one of the followings: the first bit is set to <NUM> if a non-primary <NUM> channel is punctured from a lowest frequency <NUM> channel of the P160; the first bit is set to <NUM> if the non-primary <NUM> channel is punctured from a second lowest frequency <NUM> channel of the P160; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of any <NUM> channel of the P160; or the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of any <NUM> channel of the P160. In some embodiments, the RU allocation subfield of each user information field in the MU-RTS trigger frame is set to indicate the one <NUM>+<NUM>+<NUM> tone MRU as at least one of the followings: the first bit is set to <NUM> if the non-primary <NUM> channel is punctured from the lowest frequency <NUM> channel of the P160; the first bit is set to <NUM> if the non-primary <NUM> channel is punctured from the second lowest frequency <NUM> channel of the P160; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of any <NUM> channel of the P160; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of any <NUM> channel of the P160; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a third lowest frequency <NUM> channel of any <NUM> channel of the P160; or the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a fourth lowest frequency <NUM> channel of any <NUM> channel of the P160.

In some embodiments, the RU allocation subfield of each user information field in the MU-RTS trigger frame is set to indicate the one 2x996+<NUM> tone MRU as at least one of the followings: the first bit is set to <NUM> if the punctured non-primary <NUM> channel is a part of a lowest frequency <NUM> channel of any <NUM> channel; the first bit is set to <NUM> if the punctured non-primary <NUM> channel is a part of a second lowest frequency <NUM> channel of any <NUM> channel; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of any <NUM> channel in a lower consecutive <NUM> portion of the <NUM> channel; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of any <NUM> channel in the lower consecutive <NUM> portion of the <NUM> channel; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of any <NUM> channel in an upper consecutive <NUM> portion of the <NUM> channel; or the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of any <NUM> channel in the upper consecutive <NUM> portion of the <NUM> channel. In some embodiments, the RU allocation subfield of each user information field in the MU-RTS trigger frame is set to indicate the one 3x996 tone MRU as at least one of the followings: the first bit is set to <NUM> if a punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of any <NUM> channel; the first bit is set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of any <NUM> channel; or the remaining bits are set to <NUM>.

In some embodiments, the RU allocation subfield of each user information field in the MU-RTS trigger frame is set to indicate the one 3x996+<NUM> tone MRU as at least one of the followings: the first bit is set to <NUM> if a punctured non-primary <NUM> channel is a part of a lowest frequency <NUM> channel of any <NUM> channel; the first bit is set to <NUM> if the punctured non-primary <NUM> channel is a part of a second lowest frequency <NUM> channel of any <NUM> channel; the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a lowest frequency <NUM> channel of any <NUM> channel; or the remaining bits are set to <NUM> if the punctured non-primary <NUM> channel is a second lowest frequency <NUM> channel of any <NUM> channel.

In some embodiments, the MU-RTS trigger frame and/or the CTS frame response is operated in an extremely high throughput (EHT) wireless local area network (WLAN) or a post-EHT WLAN.

Abbreviations and acronyms of some embodiment of the present disclosure are illustrated in Table <NUM>.

<FIG> illustrates an example of multi-user ready-to-send (MU-RTS)/clear-to-send (CTS)/downlink (DL) extremely high throughput (EHT) MU physical layer (PHY) protocol data unit (PPDU)/acknowledgment responses according to the present disclosure. <FIG> illustrates that, in some embodiments, in IEEE <NUM>. 11be EHT WLAN, a MU-RTS trigger/CTS frame exchange procedure allows an AP to initiate a TXOP and protect TXOP frame exchanges. <FIG> illustrates an example of the exchange of MU-RTS trigger frame and simultaneous CTS frame responses to protect an EHT MU PPDU and acknowledgement responses in an IEEE <NUM>. 11be EHT WLAN.

<FIG> illustrates a trigger frame format according to the present disclosure. <FIG> illustrates that, in some embodiments, a MU-RTS trigger frame is used to solicit simultaneous CTS frame transmissions from multiple HE STAs and/or EHT STAs. The MU-RTS trigger frame is one of various types of trigger frame. The trigger frame format is illustrated in <FIG>, which includes a common information field and a user information list field comprising one or more user information fields. The formats of the common information field and user information field depend on the type of trigger frame.

<FIG> illustrates a format of a common information field of a MU-RTS trigger frame according to the present disclosure. <FIG> illustrates that, in some embodiments, an enhanced trigger frame flag subfield is set to a first value (such as <NUM>) to indicate a trigger frame compliant with the IEEE <NUM>. 11ax specification, and the enhanced trigger frame flag subfield is set to a second value (such as <NUM>) to indicate an enhanced trigger frame compliant with the IEEE <NUM>. 11be specification. If the enhanced trigger frame flag subfield is set to the first value (such as <NUM>), the UL BW extension subfield is reserved, and the UL BW subfield indicates the bandwidth of the PPDU carrying the MU-RTS trigger frame, which is <NUM>, <NUM>, <NUM>, or <NUM>/<NUM>+<NUM>. If the enhanced trigger frame flag subfield is set to a second value (such as <NUM>), the UL BW subfield, together with the UL BW extension subfield, indicates the bandwidth of the PPDU carrying the MU-RTS trigger frame, which is <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>.

<FIG> illustrates a format of a user information field of a MU-RTS trigger frame according to the present disclosure. <FIG> illustrates that, in some embodiments, a HE/EHT format subfield is set to a first value (such as <NUM>) to indicate HE format, and the HE/EHT format subfield is set to a second value (such as <NUM>) to indicate EHT format. The value of the HE/EHT format subfield of a user information field determines how the remaining subfields of the user information field are interpreted. If the HE/EHT format subfield of a user information field is set to the first value (such as <NUM>), a lower/upper <NUM> segment subfield is reserved, and an RU allocation subfield indicates whether the CTS frame response is to be sent by the STA indicated by an AID12 subfield on a primary <NUM> channel (P20), a primary <NUM> channel (P40), a primary <NUM> channel (P80) or <NUM>/<NUM>+<NUM> channel. If the HE/EHT format subfield of a user information field is set to the second value (such as <NUM>), the RU allocation subfield, together with the lower/upper <NUM> segment subfield, indicates how the CTS frame response is to be sent by the STA indicated by the AID12 subfield.

According to some embodiments of the present disclosure, a CTS frame sent in response to a MU-RTS trigger frame shall be carried in a non-HT or non-HT duplicate PPDU, which is transmitted on the <NUM> channels indicated in the RU allocation subfield and the lower/upper <NUM> segment subfield of the user Information field of the MU-RTS trigger frame. According to some embodiments of the present disclosure, in each <NUM> channel occupied by the PPDU that contains a MU-RTS trigger frame, a transmitter of the MU-RTS trigger frame shall request at least one STA to send a CTS frame response that occupies the <NUM> channel. The transmitter of a MU-RTS trigger frame shall not request a non-AP STA to send a CTS frame response in a <NUM> channel that is not occupied by the PPDU that contains the MU-RTS trigger frame. According to some embodiments of the present disclosure, when receiving a MU-RTS trigger frame from an AP or a CTS frame from a STA, a third-party STA may update its NAV according to the value of the duration field of MU-RTS trigger frame or CTS frame and avoid to access channel when its NAV indicates channel busy.

<FIG> illustrates a schematic diagram illustrating settings for a resource unit (RU) allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, if a HE/EHT format subfield of a user information field is set to a second value (such as <NUM>), the RU allocation subfield, together with the lower/upper <NUM> segment subfield, indicates whether a CTS frame response is to be sent by the STA indicated by an AID12 subfield on a primary <NUM> channel (P20), a primary <NUM> channel (P40), a primary <NUM> channel (P80), a primary <NUM> channel (P160), or <NUM> channel. The settings for the RU allocation subfield and lower/upper <NUM> segment subfield are illustrated in <FIG>. The lower/upper <NUM> segment subfield is set to a first value (such as <NUM>) to indicate the P20, the P40, the P80, or the P160; while the lower/upper <NUM> segment subfield is set to the second value (such as <NUM>) to indicate the <NUM> channel. The RU allocation subfield is set to indicate the P20 as follows: a first bit, B0, is set to <NUM> if the P20 is the only <NUM> channel, a part of the only <NUM> channel, or a part of the P80 which is the only <NUM> channel or the lowest frequency <NUM> channel of the P160; and B0 set to <NUM> if the P20 is a part of the P80 which is the second lowest frequency <NUM> channel of the P160. The remaining bits, B7-B1 (B7, B6, B5, B4, B3, B2, and B1), are set to <NUM> if the P20 is the only <NUM> channel or the lowest frequency <NUM> channel of the only <NUM> channel or P80. B7-B1 are set to <NUM> if the P20 is the second lowest frequency <NUM> channel in the only <NUM> channel or P80. B7-B1 are set to <NUM> if the P20 is the third lowest frequency <NUM> channel in the P80. B7-B1 are set to <NUM> if the P20 is the fourth lowest frequency <NUM> channel in the P80. The RU allocation subfield has <NUM> bits. The first bit refers to B0 and is the least significant bit (LSB). The remaining bits refer to B1 to B7 (B7 to B1).

The RU allocation subfield is set to indicate the P40 as follows: B0 is set to <NUM> if the P40 is the only <NUM> channel or a part of the P80 which is the only <NUM> channel or the lowest frequency <NUM> channel of the P160; and B0 is set to <NUM> if the P40 is a part of the P80 which is the second lowest frequency <NUM> channel of the P160. B7-B1 are set to <NUM> if the P40 is the only <NUM> channel or the lowest frequency <NUM> channel of the P80. B7-B1 are set to <NUM> if the P40 is the second lowest frequency <NUM> channel in the P80.

The RU Allocation subfield is set to indicate the P80 as follows: B0 is set to <NUM> if the P80 is the only <NUM> channel or the lowest frequency <NUM> channel in the P160 and set to <NUM> if the P80 is the second lowest frequency <NUM> channel in the P160. B7-B1 are set to <NUM>. In addition, B0 of the RU allocation subfield is set to <NUM> and B7-B1 of the RU allocation subfield are set to <NUM> to indicate the P160. B0 of the RU allocation subfield is set to <NUM> and B7-B1 of the RU allocation subfield are set to <NUM> to indicate the <NUM> channel. A STA ignores B0 of the RU allocation subfield and the lower/upper <NUM> segment subfield for <NUM> indication.

According to the above embodiment, the settings of RU allocation subfield for indicating P20, P40, P80, and P160 is backward compatible to the settings of RU allocation subfield for indicating P20, P40, P80, and <NUM>/<NUM>+<NUM> channel in the IEEE <NUM>. 11ax specification, which minimizes implementation complexity.

<FIG> illustrates an example of the exchange of MU-RTS trigger frame and simultaneous CTS frame responses on the P80 in a TXOP according to the present disclosure. In this example, a MU-RTS trigger frame is transmitted in a non-HT duplicate PPDU on the P80. Further, in the user information field addressed to STA1, the lower/upper <NUM> segment subfield is set to <NUM>; and a first bit, B0, and the remaining bits, B7-B1, of the RU allocation subfield are set to <NUM> and <NUM>, respectively; while in the user information field addressed to STA2, the lower/upper <NUM> segment subfield is set to <NUM>; and B0 and B7-B1 of RU allocation subfield are set to <NUM> and <NUM>, respectively. In other words, the MU-RTS trigger frame requests STA1 to transmit a CTS frame response in a non-HT PPDU on the P20 which is the fourth lowest frequency <NUM> channel in the P80 and requests STA2 to transmit a CTS frame response in a non-HT duplicate PPDU on the P80. In this example, even if the transmissions following the MU-RTS trigger/CTS frame exchange in the TXOP occupy a partial BW of the P80 (e.g. one <NUM>+<NUM> tone MRU), the MU-RTS trigger frame has to request at least one of STA1 and STA2 to transmit a CTS frame response in a non-HT duplicate PPDU on the P80, which may cause TXOP overprotection.

According to another embodiment, if the HE/EHT format subfield of a user information field is set to a second value (such as <NUM>), the RU allocation subfield, together with the lower/upper <NUM> segment subfield, further indicates whether the CTS frame response is to be sent by the STA indicated by the AID12 subfield on the P80, P160 or <NUM> channel in which at least one <NUM> channel is punctured. The P80, P160 or <NUM> channel in which at least one <NUM> channel is punctured is one <NUM>+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the P80, one <NUM>+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the P160, one <NUM>+<NUM>+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the P160, 2x996+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from any consecutive <NUM> portion of the <NUM> channel, one 3x996 tone MRU which results from puncturing any non-primary <NUM> channel from the <NUM> channel, or one 3x996+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the <NUM> channel.

In some embodiments, large size MRUs defined for downlink (DL) and uplink (UL) transmissions in non-OFDMA format are as follows: <NUM>+<NUM> tone MRU, <NUM>+<NUM> tone MRU, <NUM>+<NUM>+<NUM> tone MRU, 2x996+<NUM> tone MRU, 3x996 tone MRU, and 3x996+<NUM> tone MRU. <FIG> illustrates four allowed <NUM>+<NUM> tone MRUs in non-OFDMA <NUM> EHT PPDU according to the present disclosure. <FIG> illustrates that, in some embodiments, the <NUM>+<NUM> tone MRU is allowed in non-OFDMA <NUM> EHT PPDU. The <NUM>+<NUM> tone MRU is obtained by puncturing any one of four <NUM>-tone RUs in the <NUM> EHT PPDU. <FIG> illustrates four allowed <NUM>+<NUM> tone MRUs in non-OFDMA <NUM> EHT PPDU according to the present disclosure. <FIG> illustrates that, in some embodiments, the <NUM>+<NUM> tone MRU is allowed in non-OFDMA <NUM> EHT PPDU. The <NUM>+<NUM> tone MRU is obtained by puncturing any one of four <NUM>-tone RUs in the <NUM> EHT PPDU. <FIG> illustrates eight allowed <NUM>+<NUM>+<NUM> tone MRUs in non-OFDMA <NUM> EHT PPDU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the <NUM>+<NUM>+<NUM> tone MRU is allowed in non-OFDMA <NUM> EHT PPDU. The <NUM>+<NUM>+<NUM> tone MRU is obtained by puncturing any one of eight <NUM>-tone RUs in the <NUM> EHT PPDU. <FIG> illustrates twelve allowed 2x996+<NUM> tone MRUs in non-OFDMA <NUM> EHT PPDU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the 2x996+<NUM> tone MRU is allowed in non-OFDMA <NUM> EHT PPDU. The 2x <NUM>+<NUM> tone MRU is obtained by puncturing any one of six <NUM>-tone RUs in <NUM> transmission defined as <NUM> EHT PPDU with <NUM> punctured. <FIG> illustrates four allowed 3x996 tone MRUs in non-OFDMA <NUM> EHT PPDU according to the present disclosure. <FIG> illustrates that, in some embodiments, the 3x996 tone MRU is allowed in non-OFDMA <NUM> EHT PPDU. The 3x996 tone MRU is obtained by puncturing any one of four <NUM>-tone RUs in the <NUM> EHT PPDU. <FIG> illustrates eight allowed 3x996+<NUM> tone MRUs in non-OFDMA <NUM> EHT PPDU according to the present disclosure. <FIG> illustrates that, in some embodiments, the 3x996+<NUM> tone MRU is allowed in non-OFDMA <NUM> EHT PPDU. The 3x996+<NUM> tone MRU is obtained by puncturing any one of eight <NUM>-tone RUs in the <NUM> EHT PPDU.

In some embodiments, the P80 in which the at least one <NUM> channel is punctured comprises one <NUM>+<NUM> tone multiple resource unit (MRU). In some embodiments, the P80 in which at least one <NUM> channel is punctured is one <NUM>+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the P80. In some embodiments, the P160 in which the at least one <NUM> channel is punctured comprises one <NUM>+<NUM> tone MRU or one <NUM>+<NUM>+<NUM> tone MRU. In some embodiments, the P160 in which at least one <NUM> channel is punctured is one <NUM>+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the P160, or one <NUM>+<NUM>+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the P160. In some embodiments, the <NUM> channel in which the at least one <NUM> channel is punctured comprises one 2x996+<NUM> tone MRU, one 3x996 tone MRU, or one 3x996+<NUM> tone MRU. In some embodiments, the <NUM> channel in which at least one <NUM> channel is punctured is 2x996+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from any consecutive <NUM> portion of the <NUM> channel, one 3x996 tone MRU which results from puncturing any non-primary <NUM> channel from the <NUM> channel, or one 3x996+<NUM> tone MRU which results from puncturing any non-primary <NUM> channel from the <NUM> channel.

According to an embodiment, the lower/upper <NUM> segment subfield is set to a first value (such as <NUM>) if the P80, P160 or <NUM> channel in which at least one <NUM> channel is punctured is one <NUM>+<NUM> tone MRU, one <NUM>+<NUM> tone MRU, or one <NUM>+<NUM>+<NUM> tone MRU. In some examples, the lower/upper <NUM> segment subfield is set to a first value (such as <NUM>) if the P80 in which at least one <NUM> channel is punctured is one <NUM>+<NUM> tone MRU. The lower/upper <NUM> segment subfield is set to a first value (such as <NUM>) if the P160 in which at least one <NUM> channel is punctured is one <NUM>+<NUM> tone MRU, or one <NUM>+<NUM>+<NUM> tone MRU. According to an embodiment, the lower/upper <NUM> segment subfield is set to <NUM> if the P80, P160 or <NUM> channel in which at least one <NUM> channel is punctured is one 2x996+<NUM> tone MRU, one 3x996 tone MRU or one 3x996+<NUM> tone RU and the at least one <NUM> channel is punctured from the lowest frequency <NUM> channel of <NUM> channel; and set to <NUM> if the P80, P160 or <NUM> channel in which at least one <NUM> channel is punctured is one 2x996+<NUM> tone MRU, one 3x996 tone MRU or one 3x996+<NUM> tone RU and the at least one <NUM> channel is punctured from the second lowest frequency <NUM> channel of <NUM> channel. In some examples, the lower/upper <NUM> segment subfield is set to <NUM> if the <NUM> channel in which at least one <NUM> channel is punctured is one 2x996+<NUM> tone MRU, one 3x996 tone MRU or one 3x996+<NUM> tone RU and the at least one <NUM> channel is punctured from the lowest frequency <NUM> channel of <NUM> channel; and set to <NUM> if the <NUM> channel in which at least one <NUM> channel is punctured is one 2x996+<NUM> tone MRU, one 3x996 tone MRU or one 3x996+<NUM> tone RU and the at least one <NUM> channel is punctured from the second lowest frequency <NUM> channel of <NUM> channel. In some embodiments, the first value and the second value have different values. In some embodiments, the first value is one of <NUM> and <NUM>, and the second value is the other of <NUM> and <NUM>.

<FIG> illustrates settings for an RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame for indicating one <NUM>+<NUM> tone multiple resource unit (MRU) according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the RU allocation subfield is set to indicate the <NUM>+<NUM> tone MRU as follows: A first bit, B0, is set to <NUM> if a non-primary <NUM> channel is punctured from the P80 which is the only <NUM> channel or the lowest frequency <NUM> channel of the P160. B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the P80 which is the second lowest frequency <NUM> channel of the P160. The remaining bits, B7-B1, are set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of the P80. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of the P80. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the third lowest frequency <NUM> channel of the P80. B7-B <NUM> are set to <NUM> if the punctured non-primary <NUM> channel is the fourth lowest frequency <NUM> channel of the P80. In some embodiments, the RU allocation subfield is set to indicate the <NUM>+<NUM> tone MRU as follows: A first bit, B0, is set to <NUM> if a non-primary <NUM> channel is punctured from the P80 which is the only <NUM> channel or the lowest frequency <NUM> channel of the P160. B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the P80 which is the second lowest frequency <NUM> channel of the P160. The values of the first bit B0 and the remaining bits B1 to B7 are examples, and the disclosure is not limited to this. In some embodiments, the first bit B0 can be <NUM> or <NUM>. In some embodiments, the remaining bits B1 to B7 (B1, B2, B3, B4, B5, B6, and B7) have different values from the above example values and the values of B1 to B7 are equal to or greater than <NUM> and equal to or less than <NUM>. The RU allocation subfield has <NUM> bits. The first bit refers to B0 and is the least significant bit (LSB). The remaining bits refer to B1 to B7 (B7 to B1).

<FIG> illustrates settings for an RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame for indicating one <NUM>+<NUM> tone MRU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the RU allocation subfield is set to indicate the <NUM>+<NUM> tone MRU as follows: B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the lowest frequency <NUM> channel of the P160. B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the second lowest frequency <NUM> channel of the P160. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel of the P160. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel of the P160. In some embodiments, the RU allocation subfield is set to indicate the <NUM>+<NUM> tone MRU as follows: B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the lowest frequency <NUM> channel of the P160. B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the second lowest frequency <NUM> channel of the P160. The values of the first bit B0 and the remaining bits B1 to B7 are examples, and the disclosure is not limited to this. In some embodiments, the first bit B0 can be <NUM> or <NUM>. In some embodiments, B1 to B7 (B1, B2, B3, B4, B5, B6, and B7) have different values from the above example values and the values of B1 to B7 are equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> illustrates settings for an RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame for indicating one <NUM>+<NUM>+<NUM> tone MRU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the RU allocation subfield is set to indicate the <NUM>+<NUM>+<NUM> tone MRU as follows: B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the lowest frequency <NUM> channel of the P160. B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the second lowest frequency <NUM> channel of the P160. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel of the P160. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel of the P160. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the third lowest frequency <NUM> channel of any <NUM> channel of the P160. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the fourth lowest frequency <NUM> channel of any <NUM> channel of the P160. In some embodiments, the RU allocation subfield is set to indicate the <NUM>+<NUM>+<NUM> tone MRU as follows: B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the lowest frequency <NUM> channel of the P160. B0 is set to <NUM> if a non-primary <NUM> channel is punctured from the second lowest frequency <NUM> channel of the P160. The values of the first bit B0 and the remaining bits B1 to B7 are examples, and the disclosure is not limited to this. In some embodiments, the first bit B0 can be <NUM> or <NUM>. In some embodiments, B1 to B7 (B1, B2, B3, B4, B5, B6, and B7) have different values from the above example values and the values of B1 to B7 are equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> illustrates settings for an RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame for indicating one 2x996+<NUM> tone MRU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the RU allocation subfield is set to indicate 2x996+<NUM> tone MRU as follows: B0 is set to <NUM> if the punctured non-primary <NUM> channel is a part of the lowest frequency <NUM> channel of any <NUM> channel; and set to <NUM> if the punctured non-primary <NUM> channel is a part of the second lowest frequency <NUM> channel of any <NUM> channel. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel in lower consecutive <NUM> portion of the <NUM> channel. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel in lower consecutive <NUM> portion of the <NUM> channel. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel in upper consecutive <NUM> portion of the <NUM> channel. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel in upper consecutive <NUM> portion of the <NUM> channel. In some examples, the 2x <NUM>+<NUM> tone MRU is obtained by puncturing any one of five non-primary <NUM> channels in <NUM> transmission defined as <NUM> EHT PPDU with <NUM> punctured. In some embodiments, the RU allocation subfield is set to indicate 2x996+<NUM> tone MRU as follows: B0 is set to <NUM> if the punctured non-primary <NUM> channel is a part of the lowest frequency <NUM> channel of any <NUM> channel; and set to <NUM> if the punctured non-primary <NUM> channel is a part of the second lowest frequency <NUM> channel of any <NUM> channel. The values of the first bit B0 and the remaining bits B1 to B7 are examples, and the disclosure is not limited to this. In some embodiments, the first bit B0 can be <NUM> or <NUM>. In some embodiments, B1 to B7 (B1, B2, B3, B4, B5, B6, and B7) have different values from the above example values and the values of B1 to B7 are equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> illustrates settings for an RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame for indicating one 3x996 tone MRU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the RU allocation subfield is set to indicate 3x996 tone MRU as follows: B0 of the RU Allocation subfield is set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel; and set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel. B7-B1 are set to <NUM>. In some embodiments, the RU allocation subfield is set to indicate 3x996 tone MRU as follows: B0 of the RU Allocation subfield is set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel; and set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel. The values of the first bit B0 and the remaining bits B1 to B7 are examples, and the disclosure is not limited to this. In some embodiments, the first bit B0 can be <NUM> or <NUM>. In some embodiments, B1 to B7 (B1, B2, B3, B4, B5, B6, and B7) have different values from the above example values and the values of B1 to B7 are equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> illustrates settings for an RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame for indicating one 3x996+<NUM> tone MRU according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, the RU allocation subfield is set to indicate 3x996+<NUM> tone MRU as follows: B0 is set to <NUM> if the punctured non-primary <NUM> channel is a part of the lowest frequency <NUM> channel of any <NUM> channel; and set to <NUM> if the punctured non-primary <NUM> channel is a part of the second lowest frequency <NUM> channel of any <NUM> channel. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the lowest frequency <NUM> channel of any <NUM> channel of the <NUM> channel. B7-B1 are set to <NUM> if the punctured non-primary <NUM> channel is the second lowest frequency <NUM> channel of any <NUM> channel of the <NUM> channel. In some embodiments, the RU allocation subfield is set to indicate 3x996+<NUM> tone MRU as follows: B0 is set to <NUM> if the punctured non-primary <NUM> channel is a part of the lowest frequency <NUM> channel of any <NUM> channel; and set to <NUM> if the punctured non-primary <NUM> channel is a part of the second lowest frequency <NUM> channel of any <NUM> channel. The values of the first bit B0 and the remaining bits B1 to B7 are examples, and the disclosure is not limited to this. In some embodiments, the first bit B0 can be <NUM> or <NUM>. In some embodiments, B1 to B7 (B1, B2, B3, B4, B5, B6, and B7) have different values from the above example values and the values of B1 to B7 are equal to or greater than <NUM> and equal to or less than <NUM>.

<FIG> is a schematic diagram illustrating another example of a MU-RTS trigger frame soliciting CTS frame responses on P80 according to an embodiment of the present disclosure. <FIG> illustrates that, in some embodiments, a MU-RTS trigger frame is transmitted in a non-HT duplicate PPDU on the <NUM>+<NUM> tone MRU comprising the P20 and secondary <NUM> channel (S40) where the P20 is the fourth lowest frequency <NUM> channel in the P80. Further, in the user information field addressed to STA1, the lower/upper <NUM> segment subfield is set to <NUM>; and B0 and B7-B1 of the RU allocation subfield are set to <NUM> and <NUM>, respectively. In the user information field addressed to STA2, the lower/upper <NUM> Segment subfield is set to <NUM>; and B0 and B7-B1 of RU allocation subfield are set to <NUM> and <NUM> respectively. In other words, the MU-RTS trigger frame requests STA1 to transmit a CTS frame response in a non-HT PPDU on the P20 and STA2 to transmit a CTS frame response in a non-HT duplicate on the <NUM>+<NUM> tone MRU comprising the P20 and S40. As a result, TXOP overprotection can be avoided when the transmissions following the MU-RTS trigger/CTS frame exchange occupy the <NUM>+<NUM> tone MRU comprising the P20 and S40.

According to yet another embodiment, the settings of a RU allocation subfield and a lower/upper <NUM> segment subfield in a MU-RTS trigger frame are the same as illustrated in <FIG>. In other words, the RU allocation subfield and the lower/upper <NUM> segment subfield of a user information field for a STA indicate whether a CTS frame response is to be sent by the STA on a P20, a P40, a P80, a P160, or <NUM> channel. However, how a STA sends its CTS frame response depends on not only the RU allocation information indicated in the RU allocation subfield and the lower/upper <NUM> segment subfield of the corresponding user information field in the MU-RTS Trigger frame, but also a channel puncturing pattern indicated in a most recently received information element by the STA. The information element which indicates the channel puncturing pattern may be an EHT Operation element, which may be included in a Management frame such as a Beacon frame, a Probe Response frame, an Association Response frame, or an Reassociation Response frame.

<FIG> illustrates a format of an EHT Operation element according to the present disclosure The EHT Operation element may comprise an EHT Operation Information field. <FIG> illustrates a format of the EHT Operation Information field of the EHT Operation element according to an embodiment of the present disclosure. The EHT Operation Information field may comprise a Channel Width subfield, a (Channel Center Frequency Segment <NUM>) CCFS0 subfield, a (Channel Center Frequency Segment <NUM>) CCFS1 subfield, and a Punctured Channel Indication subfield. The Channel Width subfield indicates the EHT BSS (basic service set) bandwidth, which is <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>. For a <NUM>, <NUM>, or <NUM> BSS bandwidth, the CCFS0 subfield indicates the channel center frequency index for the <NUM>, <NUM>, or <NUM> channel on which the EHT BSS operates. For a <NUM> BSS bandwidth, the CCFS0 subfield indicates the channel center frequency index of the <NUM> channel segment that contains the primary channel; and the CCFS <NUM> subfield indicates the channel center frequency index of the <NUM> channel on which the EHT BSS operates. For a <NUM> BSS bandwidth, the CCFS0 subfield indicates the channel center frequency index of the <NUM> channel segment that contains the primary channel; and the CCFS1 subfield indicates the channel center frequency index of the <NUM> channel on which the EHT BSS operates.

The Punctured Channel Indication subfield indicates a channel puncturing pattern; and the size of the Punctured Channel Indication subfield depends on the setting of the Channel Width subfield. If the Channel Width subfield is set to indicate <NUM> or <NUM> EHT BSS bandwidth, the Punctured Channel Indication subfield is not present in the EHT Operation Information field. If the Channel Width subfield is set to indicate <NUM> or <NUM> EHT BSS bandwidth, the Punctured Channel Indication subfield comprises an <NUM>-bit bitmap. The <NUM>-bit bitmap tells which <NUM> channel is punctured in the <NUM> or <NUM> BSS operating channel, where B0 applies to the lowest frequency <NUM> channel and B7 to the highest frequency <NUM> channel. For each of the bits B0-B7, a value of <NUM> indicates that the corresponding <NUM> channel is punctured, and a value of <NUM> is used otherwise. In terms of <NUM> EHT BSS bandwidth, each of the bits B4-B7 is reserved or set to <NUM>. If the Channel Width subfield is set to indicate <NUM> EHT BSS bandwidth, the Punctured Channel Indication subfield comprises a <NUM>-bit bitmap. The <NUM>-bit bitmap tells which <NUM> channel is punctured in the <NUM> BSS operating channel, where B0 applies to the lowest frequency <NUM> channel and B <NUM> to the highest frequency <NUM> channel. For each of the bits B0-B15, a value of <NUM> indicates that the corresponding <NUM> channel is punctured, and a value of <NUM> is used otherwise.

<FIG> illustrates an example of the exchange of MU-RTS trigger frame and simultaneous CTS frame responses on the P80 in a TXOP according to the present disclosure. In this example, a MU-RTS trigger frame is transmitted in a non-HT duplicate PPDU on the <NUM>+<NUM> tone MRU comprising the P20 and S40 where the P20 is the fourth lowest frequency <NUM> channel in the P80. Further, in the user information field addressed to STA1, the lower/upper <NUM> segment subfield is set to <NUM>; and a first bit, B0, and the remaining bits, B7-B1, of the RU allocation subfield are set to <NUM> and <NUM>, respectively; while in the user information field addressed to STA2, the lower/upper <NUM> segment subfield is set to <NUM>; and B0 and B7-B1 of RU allocation subfield are set to <NUM> and <NUM>, respectively. In other words, the MU-RTS trigger frame requests STA1 to transmit a CTS frame response in a non-HT PPDU on the P20 which is the fourth lowest frequency <NUM> channel in the P80 and requests STA2 to transmit a CTS frame response in a non-HT duplicate PPDU on the P80. On the other hand, the most recently received EHT Operation element by STA2 indicates that the third lowest frequency <NUM> channel in the P80 is punctured. After considering both the RU allocation information in the MU-RTS trigger frame and the channel puncturing pattern in the EHT Operation element, STA2 transmits a CTS frame response in a non-HT duplicate PPDU on the <NUM>+<NUM> tone MRU comprising the P20 and S40. As a result, TXOP overprotection can be avoided when the transmissions following the MU-RTS trigger/CTS frame exchange occupy the <NUM>+<NUM> tone MRU comprising the P20 and S40.

Further, post-EHT WLAN can be the next-generation WLAN immediately after EHT WLAN. According to some embodiments of the present disclosure, HE STAs, EHT STAs, and post-EHT STAs may coexist in a post-EHT BSS. The MU-RTS trigger/CTS frame exchange procedure can be used for TXOP protection in post-EHT WLAN in a similar manner to IEEE <NUM>. 11be EHT WLAN.

In summary, the above embodiments propose an access point (AP), a station (STA), and a wireless communication method, which can solve issues in the prior art, improve transmit opportunity (TXOP) protection, provide a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner, achieve extremely high throughput, provide good communication performance, and/or provide high reliability. The MU-RTS Trigger/CTS frame exchange procedure can be used for TXOP protection in IEEE <NUM>. 11be EHT WLAN in an efficient manner. In the above embodiments, an AP transmits a MU-RTS trigger frame to a plurality of STAs, which indicates whether the CTS frame response is to be sent by each of the plurality of STAs on the primary <NUM> channel (P80), primary <NUM> channel (P160) or <NUM> channel in which at least one <NUM> channel is punctured.

Commercial interests for some embodiments are as follows. Solving issues in the prior art. Improving transmit opportunity (TXOP) protection. Providing a MU-RTS trigger/CTS frame exchange procedure for TXOP protection in an efficient manner. Achieving extremely high throughput (EHT). Providing a good communication performance. Providing a high reliability. Some embodiments of the present disclosure are used by chipset vendors, communication system development vendors, automakers including cars, trains, trucks, buses, bicycles, moto-bikes, helmets, and etc., drones (unmanned aerial vehicles), smartphone makers, communication devices for public safety use, AR/VR device maker for example gaming, conference/seminar, education purposes. Some embodiments of the present disclosure are a combination of "techniques/processes" that can be adopted in communication specification and/ or communication standards such as IEEE specification and/or to standards create an end product. Some embodiments of the present disclosure propose technical mechanisms.

<FIG> is a block diagram of an example system <NUM> for wireless communication according to the present disclosure. Embodiments described herein may be implemented into the system using any suitably configured hardware and/or software. <FIG> illustrates the system <NUM> including a radio frequency (RF) circuitry <NUM>, a baseband circuitry <NUM>, an application circuitry <NUM>, a memory/storage <NUM>, a display <NUM>, a camera <NUM>, a sensor <NUM>, and an input/output (I/O) interface <NUM>, coupled with each other at least as illustrated. The application circuitry <NUM> may include a circuitry such as, but not limited to, one or more single-core or multi-core processors. The processors may include any combination of general-purpose processors and dedicated processors, such as graphics processors, application processors. The processors may be coupled with the memory/storage and configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems running on the system.

In various embodiments, the baseband circuitry <NUM> may include circuitry to operate with signals that are not strictly considered as being in a baseband frequency. For example, in some embodiments, baseband circuitry may include circuitry to operate with signals having an intermediate frequency, which is between a baseband frequency and a radio frequency. The RF circuitry <NUM> may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. In various embodiments, the RF circuitry <NUM> may include circuitry to operate with signals that are not strictly considered as being in a radio frequency. For example, in some embodiments, RF circuitry may include circuitry to operate with signals having an intermediate frequency, which is between a baseband frequency and a radio frequency.

In various embodiments, the transmitter circuitry, control circuitry, or receiver circuitry discussed above with respect to the AP or STA may be embodied in whole or in part in one or more of the RF circuitry, the baseband circuitry, and/or the application circuitry. As used herein, "circuitry" may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and/or a memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the electronic device circuitry may be implemented in, or functions associated with the circuitry may be implemented by, one or more software or firmware modules. In some embodiments, some or all of the constituent components of the baseband circuitry, the application circuitry, and/or the memory/storage may be implemented together on a system on a chip (SOC). The memory/storage <NUM> may be used to load and store data and/or instructions, for example, for system. The memory/storage for one embodiment may include any combination of suitable volatile memory, such as dynamic random access memory (DRAM)), and/or non-volatile memory, such as flash memory.

In various embodiments, the I/O interface <NUM> may include one or more user interfaces designed to enable user interaction with the system and/or peripheral component interfaces designed to enable peripheral component interaction with the system. User interfaces may include, but are not limited to a physical keyboard or keypad, a touchpad, a speaker, a microphone, etc. Peripheral component interfaces may include, but are not limited to, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, and a power supply interface. In various embodiments, the sensor <NUM> may include one or more sensing devices to determine environmental conditions and/or location information related to the system. In some embodiments, the sensors may include, but are not limited to, a gyro sensor, an accelerometer, a proximity sensor, an ambient light sensor, and a positioning unit. The positioning unit may also be part of, or interact with, the baseband circuitry and/or RF circuitry to communicate with components of a positioning network, e.g., a global positioning system (GPS) satellite.

In various embodiments, the display <NUM> may include a display, such as a liquid crystal display and a touch screen display. In various embodiments, the system <NUM> may be a mobile computing device such as, but not limited to, a laptop computing device, a tablet computing device, a netbook, an ultrabook, a smartphone, an AR/VR glasses, etc. In various embodiments, system may have more or less components, and/or different architectures. Where appropriate, methods described herein may be implemented as a computer program. The computer program may be stored on a storage medium, such as a non-transitory storage medium.

A person having ordinary skill in the art understands that each of the units, algorithm, and steps described and disclosed in the embodiments of the present disclosure are realized using electronic hardware or combinations of software for computers and electronic hardware. Whether the functions run in hardware or software depends on the condition of application and design requirement for a technical plan. A person having ordinary skill in the art can use different ways to realize the function for each specific application while such realizations should not go beyond the scope of the present disclosure. It is understood by a person having ordinary skill in the art that he/she can refer to the working processes of the system, device, and unit in the above-mentioned embodiment since the working processes of the above-mentioned system, device, and unit are basically the same. For easy description and simplicity, these working processes will not be detailed.

Claim 1:
A wireless communication method, comprising:
transmitting (<NUM>), by an access point, AP, a multi-user ready-to-send, MU-RTS, trigger frame to a plurality of stations, STAs, wherein the MU-RTS trigger frame indicates whether a clear-to-send, CTS, frame response is to be transmitted by each of the plurality of STAs on a primary <NUM> channel, P20, a primary <NUM> channel, P40, a primary <NUM> channel, P80, a primary <NUM> channel, P160, or a <NUM> channel, and at least one <NUM> channel is punctured in the P80, the P160, or the <NUM> channel,
wherein each user information field of the MU-RTS trigger frame comprises a subfield and an RU allocation subfield, and the subfield and the RU allocation subfield of each user information field in the MU-RTS trigger frame indicate RU allocation information, and
wherein the subfield of each user information field in the MU-RTS trigger frame comprises a lower/upper <NUM> segment subfield.