Patent Description:
The invention relates to wireless communications, and more particularly to methods and apparatuses for soliciting a trigger-based (TB) physical layer protocol data unit (PPDU) transmission in a wireless local area network (WLAN) with a trigger frame.

Institute of Electrical and Electronics Engineers (IEEE) <NUM>. 11be extremely high throughput (EHT) WLAN supports a bandwidth (BW) up to <NUM>. It is expected that high efficiency (HE) stations (STAs) will exist with EHT STAs in a same EHT basic service set (BSS). In order to maximize throughput of an EHT BSS with large BW, e.g., <NUM> or <NUM>, a frequency domain aggregated physical layer protocol data unit (FD-A-PPDU) has been proposed. In IEEE <NUM> be EHT WLAN, a trigger frame can be used to solicit HE TB PPDU transmissions, EHT TB PPDU transmissions, or TB FD-A-PPDU transmission. However, it is an open issue to enhance the <NUM>. 11ax trigger frame to achieve this goal. <CIT> discloses a method for transmitting a physical layer protocol data unit (PPDU) in a transmission opportunity (TXOP) and a device using the same are provided. The device transmits a request to send (RTS) frame to a plurality of receiving stations. The RTS frame includes a bandwidth field and a plurality of allocation fields. The bandwidth field indicates a first bandwidth in which the RTS frame is transmitted. Each allocation field indicates a bandwidth in which a clear to send (CTS) frame is to be sent by a corresponding receiving station. The device determines a transmission bandwidth of a PPDU to be sent by comparing the first bandwidth with a second bandwidth which is a total bandwidth indicated by the plurality of allocation fields. <CIT> discloses systems, methods, apparatus, including computer programs encoded on computer storage media for orthogonal multiplexing of high efficiency (HE) and extremely high throughput (EHT) wireless traffic. Devices in a wireless local area network (WLAN) may operate under HE or EHT conditions. An access point (AP) may support both HE and EHT communications with WLAN devices. To enable substantially simultaneous downlink HE and EHT transmissions and substantially simultaneous uplink HE and EHT transmissions, the AP may support orthogonal frequency-division multiple access (OFDMA) of HE and EHT transmissions. For example, pre-HE and pre-EHT modulated fields, HE and EHT modulated fields, and payloads may be aligned in time for the HE and EHT transmissions. The AP may ensure orthogonality for multiplexing the HE and EHT transmissions based on the alignment. In some implementations, a trigger frame may be utilized to indicate uplink transmission alignments. <CIT> disclosure methods, devices and systems for generating enhanced trigger frames. Some implementations more specifically relate to trigger frame designs that support gains in data throughput achievable in accordance with the IEEE <NUM>. 11be amendment, and future generations, of the IEEE <NUM> standard. In some implementations, an enhanced trigger frame may be used to solicit a non-legacy trigger-based (TB) physical layer protocol convergence protocol (PLCP) protocol data unit (PPDU) from one or more wireless stations (STAs). In some implementations, the enhanced trigger frame may be configurable to support multiple versions of the IEEE <NUM> standard. For example, an enhanced trigger frame may be configured in accordance with a legacy trigger frame format or a non-legacy trigger frame format. Thus, when configured in accordance with the legacy trigger frame format, the enhanced trigger frame can also be used to a legacy TB PPDU from one or more STAs.

Embodiments of the invention provide methods and apparatuses for soliciting a TB PPDU transmission in a WLAN with a trigger frame.

According to a first aspect of the invention, various embodiments of the invention provide a method for soliciting a TB PPDU transmission in a WLAN as set out in claim <NUM> and a station therefore as set out in claim <NUM>. Additional features are set out in claims <NUM> to <NUM>.

According to a second aspect of the invention, various embodiments of the invention provide a method for soliciting a TB PPDU transmission in a WLAN as set out in claim <NUM>. Additional features are set out in claims <NUM> to <NUM>.

According to a third aspect of the invention, various embodiments of the invention provide an AP for soliciting a TB PPDU transmission in a WLAN as set out in claim <NUM>.

The invention will be described in detail with reference to the accompanying drawings, in which:.

The invention of the methods and apparatuses for soliciting a TB PPDU transmission in a WLAN with a trigger frame can also be understand as methods and apparatuses for transmitting a TB PPDU transmission in a WLAN, which is a general summary of the invention, but not limit the specific feature of AP or STA, when executes this method.

<FIG> is a schematic diagram illustrating an uplink multi-user (MU) transmission according to a non-claimed embodiment. When receiving a trigger frame from an AP which is used to solicit a TB FD-A-PPDU transmission from both HE STAs and EHT STAs, each of scheduled HE STAs and EHT STAs will transmit a TB PPDU based on the scheduling information in the received trigger frame. The TB PPDU transmitted by each of scheduled HE STAs is a HE TB PPDU while the TB PPDU transmitted by each of scheduled EHT STAs is a HE TB PPDU or an EHT TB PPDU.

Multiple HE TB PPDUs transmitted by different STAs at non-overlapping frequency-domain resource and/or spatial domain resource in a <NUM>/<NUM>/<NUM>/<NUM>/<NUM> channel can be treated as a single HE TB PPDU. Similarly, multiple EHT TB PPDUs transmitted by different STAs at non-overlapping frequency-domain resource and/or spatial domain resource in a <NUM>/<NUM>/<NUM>/<NUM>/<NUM> channel can be treated as a single EHT TB PPDU. The HE TB PPDUs and EHT TB PPDUs transmitted by all scheduled HE STAs and EHT STAs constitute a TB FD-A-PPDU. The AP will transmit a Multi-STA BlockAck (Multi-STA BA) frame in a response to the received TB FD-A-PPDU.

<FIG> is a block diagram illustrating a format of a HE TB PPDU and <FIG> is a block diagram illustrating a format of an EHT TB PPDU. In a HE TB PPDU, the Non-HT Short Training Field (L-STF), Non-HT Long Training Field (L-LTF), Non-HT SIGNAL Field (L-SIG), Repeated L-SIG field (RL-SIG field) and HE SIGNAL A field (HE-SIG-A field) are called pre-HE modulated fields while the HE Short Training Field (HE-STF), HE Long Training field (HE-LTF), Data field and Packet Extension (PE) field are called HE modulated fields. In an EHT TB PPDU, the L-STF, L-LTF, L-SIG field, RL-SIG field and U-SIG field are called pre-EHT modulated fields while the EHT Short Training Field (EHT-STF), EHT Long Training field (EHT-LTF), Data field and PE field are called EHT modulated fields.

Each HE-LTF or EHT-LTF symbol has the same Guard interval (GI) duration as each data symbol, which is <NUM>, <NUM> or <NUM>. The HE-LTF field comprises three types: 1x HE-LTF, 2x HE-LTF and 4x HE-LTF. Similarly, the EHT-LTF field comprises three types: 1x EHT-LTF, 2x EHT-LTF and 4x EHT-LTF. The duration of each 1x HE-LTF/EHT-LTF, 2x HE-LTF/EHT-LTF or 4x HE-LTF/EHT-LTF symbol without GI is <NUM>, <NUM> or <NUM>. Each data symbol without GI is <NUM>. The PE field duration of a HE TB PPDU is <NUM>, <NUM>, <NUM>, <NUM> or <NUM>; while the PE field duration of an EHT TB PPDU is <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

In an EHT BSS with a large BW (e.g., <NUM> or <NUM>), a TB FD-A-PPDU used for uplink MU transmission may comprise one HE TB PPDU and one or two EHT TB PPDUs if the HE-LTF field has a same symbol duration and a same GI duration as the EHT-LTF field.

The number of HE-LTF symbols may be the same as or different from the number of EHT-LTF symbols. When the number of HE-LTF symbols is the same as the number of EHT-LTF symbols, each HE-LTF/EHT-LTF symbol may have a different duration or a same duration from each data symbol. In other words, each HE-LTF/EHT-LTF symbol without GI may be <NUM> or <NUM>. When the number of HE-LTF symbols is different from the number of EHT-LTF symbols, each HE-LTF/EHT-LTF symbol shall have a same duration as each data symbol. In other words, each HE-LTF/EHT-LTF symbol without GI shall be <NUM>. As a result, the pre-HE modulated fields of a HE TB PPDU and the pre-EHT modulated fields of an EHT TB PPDU can be kept orthogonal in frequency domain symbol- by-symbol.

For uplink MU transmission, each scheduled HE STA may park in primary <NUM> channel (P80); while each scheduled EHT STA may park in one of non-primary <NUM> channel(s) via an enhanced Selective subchannel transmission (SST) mechanism. A non-primary <NUM> channel is an <NUM> frequency segment outside P80, e.g., secondary <NUM> channel (S80) in a <NUM> or <NUM> channel.

According to a non-claimed embodiment, in a <NUM> BW TB FD-A-PPDU, the BW allocated to HE STAs is P80 while BW allocated to EHT STAs is S80. In this case, one HE TB PPDU may be transmitted in P80 while one EHT TB PPDU may be transmitted in S80. <FIG> is <NUM> BW allocation for a TB FD-A-PPDU transmission according to a non-claimed embodiment.

In a <NUM> BW TB FD-A-PPDU, the BW allocated to HE STAs is P80 or primary <NUM> channel (P160); while the BW allocated to EHT STAs is one of two <NUM> frequency segments of secondary <NUM> channel (S160), S160, a combination of S80 and one of two <NUM> frequency segments of S160 or a combination of S80 and S160.

For a <NUM> BW FD-A-PPDU, there may have the following five options for BW allocation in the TB FD-A-PPDU:.

Option 1A: When S80 is punctured, BW allocated to HE STAs is P80 and BW allocated to EHT STAs is S160, as illustrated in <FIG>. One HE TB PPDU may be transmitted in P80 while one EHT TB PPDU may be transmitted in S160.

Option 1B: When one of two <NUM> frequency segments of S160 is punctured, BW allocated to HE STAs is P160 and BW allocated to EHT STAs is the other <NUM> frequency segment of S160, as illustrated in <FIG>. One HE TB PPDU may be transmitted in P160 while one EHT TB PPDU may be transmitted in the unpunctured <NUM> frequency segment of S160.

Option 1C: When one of two <NUM> frequency segments of S160 is punctured, BW allocated to HE STAs is P80 and BW allocated to EHT STAs is S80 and the other <NUM> frequency segment of S160, as illustrated in <FIG>. One HE TB PPDU may be transmitted in P80 while two EHT TB PPDUs may be transmitted in S80 and the unpunctured <NUM> frequency segment of S160, respectively.

Option 1D: When none of <NUM> frequency segments is punctured, BW allocated to HE STAs is P160 and BW allocated to EHT STAs is S160, as illustrated in <FIG>. One HE TB PPDU may be transmitted in P160 while one EHT TB PPDU may be transmitted in S160.

Option 1E: When none of <NUM> frequency segments is punctured, BW allocated to HE STAs is P80 and BW allocated to EHT STAs is S80 and S160, as illustrated in <FIG>. One HE TB PPDU may be transmitted in P80 while one EHT TB PPDU may be transmitted in S80 and S160.

In IEEE <NUM>. 11be EHT WLAN, a trigger frame can be used to solicit HE TB PPDU transmissions from HE STAs, EHT TB PPDU transmissions from EHT STAs, or TB FD-A-PPDU transmission from both HE STAs and EHT STAs. However, the TB PPDU transmitted by each of scheduled HE STAs is a HE TB PPDU while the TB PPDU transmitted by each of scheduled EHT STAs is a HE TB PPDU or an EHT TB PPDU. <FIG> is a schematic diagram showing an example of a trigger frame soliciting HE TB PPDU transmission from two HE STAs in a WLAN. <FIG> is a schematic diagram showing an example of a trigger frame soliciting EHT TB PPDU transmission from two EHT STAs in a WLAN. <FIG> is a schematic diagram showing an example of a trigger frame soliciting TB FD-A-PPDU transmission from one HE STA and one EHT STA in a WLAN.

<FIG> is a block diagram illustrating a trigger frame format according to one embodiment of the invention. The trigger frame format shown in <FIG> includes a common info field and a user info list field comprising one or more user info fields. The formats of the common info field and user info field depend on the type of trigger frame.

<FIG> is a block diagram illustrating an example of a user info field format of trigger frame according to one embodiment of the invention. The HE/EHT format subfield of a user info field indicates whether the user info field follows the <NUM>. 11ax HE format or the <NUM>. 11be EHT format. The value of the HE/EHT format subfield of a user info field determines how the remaining subfields of the user info field are interpreted. The HE/EHT format subfield of a user info field is set to <NUM> to indicate the <NUM>. 11ax HE format and set to <NUM> to indicate the <NUM>. 11be EHT format. When the HE/EHT format subfield of a user info field is set to indicate the <NUM>. 11ax HE format, the lower/upper <NUM> segment subfield is reserved, and the RU allocation subfield indicates a Resource unit (RU) at which a HE TB PPDU is to be transmitted by the STA indicated by the AIDI12 subfield. If the HE/EHT format subfield of a user info field is set to indicate the <NUM>. 11be EHT format, the RU allocation subfield and the lower/upper <NUM> segment subfield indicate a RU or Multiple resource unit (MRU) at which an EHT TB PPDU is to be transmitted by the STA indicated by the AID12 subfield.

<FIG> is a flowchart illustrating a method <NUM> for soliciting a TB PPDU transmission in a WLAN implemented by an AP according to some embodiments of the invention. In this embodiment of the invention, the method <NUM> is implemented by an AP. In other embodiments, the method <NUM> may be implemented by any other suitable network interface device.

At block <NUM>, a trigger frame is generated by the AP based on a type of PPDU transmissions to be solicited from a plurality of STAs in the WLAN, e.g., HE STAs and/or EHT STAs. The type of PPDU transmissions comprises HE TB PPDU transmissions or EHT TB PPDU transmissions, and one or two subfields in the trigger frame, e.g., UL BW subfield, UL BW subfield and Delta EHT UL BW, or UL BW subfield and UL BW Extension subfield, indicate a BW of the solicited TB PPDU. In a non-claimed embodiment, the type of PPDU transmissions may comprise FD-A-PPDU transmissions.

At block <NUM>, the generated trigger frame is transmitted to the plurality of STAs.

In one embodiment, a common info field of the trigger frame comprises an UL BW subfield indicating a BW of the solicited HE TB PPDU.

In one embodiment, the UL BW subfield occupies <NUM> bits in the common info field of the trigger
frame.

In one embodiment, the BW of the solicited HE TB PPDU is <NUM>, <NUM>, <NUM> or <NUM>/<NUM>+<NUM>.

In one embodiment, the BW of the solicited HE TB PPDU indicated by the UL BW subfield in the common info field of the trigger frame is in the HE SIGNAL A (HE SIG-A) field of the solicited HE TB PPDU.

In one embodiment, the common info field of the trigger frame further comprises an enhanced trigger frame flag subfield which indicates whether the trigger frame is an <NUM>. 11ax trigger frame or an enhanced trigger frame.

In one embodiment, the enhanced trigger frame includes a common info field and a user info list field comprising one or more user info fields.

In one embodiment, when the enhanced trigger frame flag subfield indicates that the trigger frame is an enhanced trigger frame, both the UL BW subfield and a Delta EHT UL BW subfield indicate a BW of the solicited EHT TB PPDU.

In one embodiment, the BW of the solicited EHT TB PPDU indicated by both the UL BW subfield and the Delta EHT UL BW subfield is in the universal SIGNAL (U-SIG) field of the solicited EHT TB PPDU.

In one embodiment, the Delta EHT UL BW subfield occupies <NUM> bits of the enhanced trigger frame.

In one embodiment, the BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

In one embodiment, the indicated BW of the solicited EHT TB PPDU is the same as the indicated BW of the solicited HE TB PPDU when the indicated BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM> or160 MHz.

In one embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW
larger than the indicated BW of the solicited HE TB PPDU when the BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM> or <NUM>.

In one embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW
smaller than the indicated BW of the solicited HE TB PPDU when the indicated BW of the solicited EHT TB PPDU is <NUM>, <NUM> or <NUM>.

In a non-claimed embodiment, when the enhanced trigger frame flag subfield indicates that the trigger frame is an enhanced trigger frame, both the UL BW subfield and a UL BW extension subfield indicate a BW of the solicited EHT TB PPDU.

In this embodiment, the BW of the solicited EHT TB PPDU indicated by both the UL BW subfield and UL BW extension subfield is in the universal SIGNAL (U-SIG) field of the solicited EHT TB PPDU.

In this embodiment, the BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

In this embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW
larger than the indicated BW of the solicited HE TB PPDU when the BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM> or <NUM>.

In this embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW
smaller than the indicated BW of the solicited HE TB PPDU when the indicated BW of the solicited EHT TB PPDU is <NUM>, <NUM> or <NUM>.

<FIG> is a flowchart illustrating a method <NUM> for soliciting a TB PPDU transmission in a WLAN implemented by a STA according to some embodiments of the invention. In this embodiment of the invention, the method <NUM> is implemented by a STA. In other embodiments, the method <NUM> may be implemented by any other suitable client device.

At block <NUM>, a trigger frame from an AP is received by a STA, e.g., a HE STA and/or an EHT STA, the trigger frame is generated based on a type of PPDU transmissions to be solicited from a plurality of STAs, e.g., HE STAs and/or EHT STAs. The type of PPDU transmissions comprises HE TB PPDU transmissions or EHT TB PPDU transmissions, and one or two subfields in the trigger frame, e.g., UL BW subfield, UL BW subfield and Delta EHT UL BW, or UL BW subfield and UL BW Extension subfield, indicate a BW of the solicited TB PPDU. In a non-claimed embodiment, the type of PPDU transmissions may comprise FD-A-PPDU transmissions.

At block <NUM>, the solicited TB PPDU in the BW indicated by the one or two subfields in the trigger frame is transmitted by the STA.

In one embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW larger than the indicated BW of the solicited HE TB PPDU when the BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM> or <NUM>.

In one embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW smaller than the indicated BW of the solicited HE TB PPDU when the indicated BW of the solicited EHT TB PPDU is <NUM>, <NUM> or <NUM>.

In this embodiment, the indicated BW of the solicited EHT TB PPDU is the same as the indicated BW of the solicited HE TB PPDU when the indicated BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM> or160 MHz.

In this embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW larger than the indicated BW of the solicited HE TB PPDU when the BW of the solicited EHT TB PPDU is <NUM>, <NUM>, <NUM> or <NUM>.

In this embodiment, the indicated BW of the solicited EHT TB PPDU is the next available BW smaller than the indicated BW of the solicited HE TB PPDU when the indicated BW of the solicited EHT TB PPDU is <NUM>, <NUM> or <NUM>.

<FIG> is a schematic diagram illustrating an AP 1500A for soliciting a TB PPDU transmission in a WLAN according to one embodiment of the invention. In this embodiment, the AP 1500A includes a generation unit 1501a and a first transmission unit 1502b. The generation unit 1501a is configured to generate a trigger frame based on a type of TB PPDU transmissions to be solicited from a plurality of STAs in the WLAN, e.g., HE STAs and/or EHT STAs. The type of TB PPDU transmissions comprises HE TB PPDU transmissions or EHT TB PPDU transmissions, and one or two subfields, e.g., UL BW subfield, UL BW subfield and Delta EHT UL BW, or UL BW subfield and UL BW Extension subfield, in the trigger frame indicate a BW of the solicited TB PPDU. In a non-claimed embodiment, the type of PPDU transmissions may comprise FD-A-PPDU transmissions.

The first transmission unit 1502b is configured to transmit the solicited TB PPDU in the BW indicated by the one or two subfields in the trigger frame.

<FIG> is a schematic diagram illustrating an AP 1500B for soliciting a TB PPDU transmission in a WLAN according to one embodiment of the invention. The AP 1500B includes a memory 1501b configured to store instructions for soliciting a TB PPDU transmission in a WLAN, and a processor 1502b communicably coupled with the memory, the processor 1502b configured to execute the instructions to cause the AP 1500B to perform the method for soliciting a TB PPDU transmission in a WLAN according to some embodiments of the invention, e.g., the method described above and illustrated in <FIG>.

<FIG> is a schematic diagram illustrating a STA 1600A for soliciting a TB PPDU transmission in a WLAN according to one embodiment of the invention. In this embodiment, the STA 1600A includes a reception unit 1601a and a second transmission unit 1602b. The reception unit 1601a is configured to receive a trigger frame which is used to solicit a type of TB PPDU transmissions from a plurality of STAs in the WLAN, e.g., HE STAs and/or EHT STAs. The type of TB PPDU transmissions comprises HE TB PPDU transmissions or EHT TB PPDU transmissions, and one or two subfields, e.g., UL BW subfield, UL BW subfield and Delta EHT UL BW, or UL BW subfield and UL BW Extension subfield, in the trigger frame indicate a bandwidth (BW) of the solicited TB PPDU. In a non-claimed embodiment, the type of PPDU transmissions may comprise FD-A-PPDU transmissions.

The second transmission unit 1602b is configured to transmit the solicited TB PPDU in the BW indicated by the one or two subfields in the trigger frame.

<FIG> is a schematic diagram illustrating a STA 1600B for soliciting a TB PPDU transmission in a WLAN according to one embodiment of the invention. The STA 1600B includes a memory 1601b configured to store instructions for soliciting a TB PPDU transmission in a WLAN, and a processor 1602b communicably coupled with the memory, the processor 1602b configured to execute the instructions to cause the STA 1600B to perform the method for soliciting a TB PPDU transmission in a WLAN according to some embodiments of the invention, e.g., the method described above and illustrated in <FIG>.

<FIG> is a block diagram illustrating an example of the common info field format of trigger frame according to the first embodiment. The enhanced trigger frame flag subfield indicates whether the trigger frame is an <NUM>. 11ax trigger frame or an enhanced trigger frame. The enhanced trigger frame flag subfield is set to <NUM> to indicate an <NUM>. 11ax trigger frame; and set to <NUM> to indicate an enhanced trigger frame. When the enhanced trigger frame flag subfield is set to indicate an <NUM>. 11ax trigger frame, the UL BW Extension subfield is reserved, and the UL BW subfield indicates the BW in the HE-SIG-A field of the solicited HE TB PPDU which is <NUM>, <NUM>, <NUM> or <NUM>/<NUM>+<NUM>. When the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, both the UL BW subfield and the UL BW extension subfield indicate the BW in the U-SIG of the solicited EHT TB PPDU which is <NUM>, <NUM>, <NUM>, <NUM> or <NUM>.

The trigger frame with the common info field shown in <FIG> can be used to solicit HE TB PPDU transmission from HE STAs or EHT TB PPDU transmission from EHT STAs. For one example, when the trigger frame is used to solicit <NUM> HE TB PPDU transmission from HE STAs, the enhanced trigger frame flag subfield of the common info field is set to indicate an <NUM>. 11ax trigger frame and the UL BW subfield is set to indicate <NUM>/<NUM>+<NUM> BW. For another example, when the trigger frame is used to solicit <NUM> EHT TB PPDU transmission from EHT STAs, the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, and both the UL BW subfield and UL BW extension subfield are set to indicate <NUM> BW.

The trigger frame with the common info field shown in <FIG> can also be used to solicit TB FD-A-PPDU transmission from both HE STAs and EHT STAs where the solicited TB FD-A-PPDU comprises one HE TB PPDU and one or two EHT TB PPDUs. In this case, the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, the UL BW extension subfield is set to <NUM> and the UL BW subfield indicates the BW in the HE-SIG-A field of the one HE TB PPDU which is the same as the BW in the U-SIG fields of the one or two EHT TB PPDUs. The UL BW subfield of the common info field of the trigger frame may be set to indicate a half of the BW of the solicited TB FD-A-PPDU. For one example, when the trigger frame is used to solicit <NUM> BW TB FD-A-PPDU transmission, the UL BW subfield is set to indicate <NUM>. For another example, when the trigger frame is used to solicit <NUM> BW TB FD-A-PPDU transmission, the UL BW subfield is set to indicate <NUM>. However, by doing so, in case of BW allocation option 1A, 1B or 1E for <NUM> BW TB FD-A-PPDU comprising one HE TB PPDU and one or two EHT TB PPDUs, the BW in the HE-SIG-A field of the one HE TB PPDU is not the same as its allocated BW and the BW in the U-SIG fields of the one or two EHT TB PPDUs is not the same as their respective allocated BW.

<FIG> is a block diagram illustrating an example of the common info field format of trigger frame according to the second embodiment. The enhanced trigger frame flag subfield is used to indicate whether the trigger frame is an <NUM>. 11ax trigger frame or an enhanced trigger frame. The enhanced trigger frame flag subfield is set to <NUM> to indicate an <NUM>. 11ax trigger frame; and set to <NUM> to indicate an enhanced trigger frame. When the enhanced trigger frame flag subfield is set to indicate an <NUM>. 11ax trigger frame, the EHT UL BW subfield is reserved, and the UL BW subfield indicates the BW in the HE-SIG-A field of the solicited HE TB PPDU. When the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, the UL BW subfield indicates the BW in the HE-SIG-A field of the one HE TB PPDU in the solicited TB FD-A-PPDU, and the EHT UL BW subfield indicates the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU.

The trigger frame with the common info field shown in <FIG> can be used to solicit HE TB PPDU transmission from HE STAs, EHT TB PPDU transmission from EHT STAs, or TB FD-A-PPDU transmission from both HE STAs and EHT STAs. For one example, when the trigger frame is used to solicit <NUM> HE TB PPDU transmission from HE STAs, the enhanced trigger frame flag subfield is set to indicate an <NUM>. 11ax trigger frame and the UL BW subfield is set to indicate <NUM>/<NUM>+<NUM> BW. For another example, when the trigger frame is used to solicit <NUM> EHT TB PPDU transmission from EHT STAs, the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame and the EHT UL BW subfield is set to indicate <NUM> BW. When the trigger frame is used to solicit FD-A-PPDU transmission from both HE STAs and EHT STAs, the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, and the values of both UL BW subfield and EHT UL BW subfield are set according to the BW and BW allocation of the solicited TB FD-A-PPDU as shown in Table <NUM>.

It should be observed from Table <NUM> that in terms of BW allocation option 1A for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW for the HE TB PPDU and the EHT UL BW subfield is set to indicate <NUM> BW for the EHT TB PPDU. In terms of BW allocation option 1B for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW for the HE TB PPDU and the EHT UL BW subfield is set to indicate <NUM> BW for the EHT TB PPDU. In terms of BW allocation option 1C for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to each of two EHT TB PPDUs is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW for the HE TB PPDU and the EHT UL BW subfield is set to indicate <NUM> BW for each of the two EHT TB PPDUs. In terms of BW allocation option 1D for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, both the UL BW subfield and the EHT UL BW subfield are set to indicate <NUM> BW. In terms of BW allocation option 1E for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW for the HE TB PPDU and the EHT UL BW subfield is set to indicate <NUM> BW since there is no <NUM> EHT TB PPDU and <NUM> transmission is obtained by puncturing an <NUM> frequency segment from <NUM> EHT TB PPDU.

According to the second embodiment, regardless of BW allocation options for <NUM> BW TB FD-A-PPDU comprising one HE TB PPDU and one or two EHT TB PPDUs, the BW in the HE-SIG-A field of the one HE TB PPDU is the same as its allocated BW and the BW in the U-SIG fields of the one or two EHT TB PPDUs is the same as their respective allocated BW.

<FIG> is a block diagram illustrating an example of the common info field format of trigger frame according to the third embodiment. The enhanced trigger frame flag subfield is used to indicate whether the trigger frame is an <NUM>. 11ax trigger frame or an enhanced trigger frame. The enhanced trigger frame flag subfield is set to <NUM> to indicate an <NUM>. 11ax trigger frame; and set to <NUM> to indicate an enhanced trigger frame. When the enhanced trigger frame flag subfield is set to indicate an <NUM>. 11ax trigger frame, the Delta EHT UL BW subfield is reserved, and the UL BW subfield indicates the BW in the HE-SIG-A field of the solicited HE TB PPDU. When the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, the UL BW subfield indicates the BW in the HE-SIG-A field of the one HE TB PPDU in the solicited TB FD-A-PPDU, and both the Delta EHT UL BW subfield and the UL BW subfield indicate the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU. In one embodiment, the Delta EHT UL BW subfield is set to <NUM> to indicate the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is the same as the BW indicated in the UL BW subfield. The BW in the U-SIG field of the solicited EHT TB PPDU and the BW in the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU could be <NUM> or <NUM> or <NUM> or <NUM>. The Delta EHT UL BW subfield is set to <NUM> to indicate the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is the next available BW larger than the BW indicated in the UL BW subfield. The Delta EHT UL BW subfield is set to <NUM> to indicate the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is the second next available BW larger than the BW indicated in the UL BW subfield. The Delta EHT UL BW subfield is set to <NUM> to indicate the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is the next available BW smaller than the BW indicated in the UL BW subfield. For example, when the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>, the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is <NUM>. When the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>, the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is <NUM>. When the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>, the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is <NUM>. When the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>, the BW in the U-SIG field of the solicited EHT TB PPDU or the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU is <NUM>. The valid combinations of the UL BW subfield indication and the Delta EHT UL BW subfield value are shown in Table <NUM>.

When the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, the UL BW subfield indicates the BW in the HE-SIG-A. As an example, the trigger frame with the common info field shown in <FIG> can be used to solicit HE TB PPDU transmission from HE STAs, EHT TB PPDU transmission from EHT STAs, or TB FD-A-PPDU transmission from both HE STAs and EHT STAs. And the TB PPDU transmitted by each of scheduled HE STAs is a HE TB PPDU while the TB PPDU transmitted by each of scheduled EHT STAs is a HE TB PPDU or an EHT TB PPDU. For one example, when the trigger frame is used to solicit <NUM> HE TB PPDU transmission from HE STAs, the enhanced trigger frame flag subfield is set to indicate an <NUM>. 11ax trigger frame and the UL BW subfield is set to indicate <NUM>/<NUM>+<NUM> BW. For another example, when the trigger frame is used to solicit <NUM> EHT TB PPDU transmission from EHT STAs, the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>. When the trigger frame is used to solicit FD-A-PPDU transmission from both HE STAs and EHT STAs, the enhanced trigger frame flag subfield is set to indicate an enhanced trigger frame, and the UL BW subfield and Delta EHT UL BW subfield are set according to the FD-A-PPDU's BW and BW allocation option as shown in Table <NUM>.

It can be observed from Table <NUM> that in terms of BW allocation option 1A for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>. In terms of BW allocation option 1B for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>. In terms of BW allocation option 1C for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to each of two EHT TB PPDUs is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>. In terms of BW allocation option 1D for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM>. In terms of BW allocation option 1E for <NUM> BW TB FD-A-PPDU, the BW allocated to one HE TB PPDU is <NUM> and the BW allocated to one EHT TB PPDU is <NUM>. As a result, the UL BW subfield is set to indicate <NUM> BW and the Delta EHT UL BW subfield is set to <NUM> since there is no <NUM> EHT TB PPDU and <NUM> transmission is obtained by puncturing an <NUM> frequency segment from <NUM> EHT TB PPDU.

According to the third embodiment, regardless of BW allocation options for <NUM> BW TB FD-A-PPDU comprising one HE TB PPDU and one or two EHT TB PPDUs, the BW in the HE-SIG-A field of the one HE TB PPDU is the same as its allocated BW and the BW in the U-SIG fields of the one or two EHT TB PPDUs is the same as their respective allocated BW.

Compared to the second embodiment where the <NUM>-bit EHT UL BW subfield is included in the common info field of the trigger frame, one more reserved bit is available in the common info field of the trigger frame for the third embodiment due to the <NUM>-bit Delta EHT UL BW subfield.

The common info field of the trigger frame comprises a UL BW subfield and a subfield.

In a first aspect, when the trigger frame is used to solicit TB FD-A-PPDU transmission where the solicited TB FD-A-PPDU comprises one HE TB PPDU and one or two EHT TB PPDUs, the UL BW subfield indicates the BW in the HE-SIG-A field of the one HE TB PPDU, which is the same as the BW in the U-SIG fields of the one or two EHT TB PPDUs; and the BW indicated in the UL BW subfield may be equal to a half of the BW of the solicited TB FD-A-PPDU. When the trigger frame is used to solicit EHT TB PPDU transmission, both the UL BW subfield and the subfield indicate the BW in the HE-SIG-A field of the solicited EHT TB PPDU.

In a second aspect, when the trigger frame is used to solicit TB FD-A-PPDU transmission or EHT TB PPDU transmission, the UL BW subfield indicates the BW in the HE-SIG-A field of the one HE TB PPDU in the solicited TB FD-A-PPDU and the subfield indicates the BW in the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU or the U-SIG field of the solicited EHT TB PPDU. The values of the UL BW subfield and the subfield may be set according to the BW and BW allocation of the solicited TB FD-A-PPDU.

In a third aspect, when the trigger frame is used to solicit TB FD-A-PPDU transmission or EHT TB PPDU transmission, the UL BW subfield indicates the BW in the HE-SIG-A field of the one HE TB PPDU in the solicited TB FD-A-PPDU, and both the UL BW subfield and the subfield indicate the BW in the U-SIG fields of the one or two EHT TB PPDUs in the solicited TB FD-A-PPDU or the U-SIG field of the solicited EHT TB PPDU.

Various embodiments of the present disclosure also provide a computer program product comprising instructions to cause a computer to perform a method for soliciting a TB PPDU transmission in a WLAN according to any embodiment of the invention, when executed thereon.

Various embodiments of the present disclosure also provide a computer program comprising instructions to cause a computer to perform a method for soliciting a TB PPDU transmission in a WLAN according to any embodiment of the invention, when executed thereon.

Various embodiments of the present disclosure also provide a non-volatile storage medium comprising computer program codes to cause a computer to perform a method for soliciting a TB PPDU transmission in a WLAN according to any embodiment of the invention, when executed thereon.

Various embodiments of the present disclosure also provide a chip configured to perform a method for soliciting a TB PPDU transmission in a WLAN according to any embodiment of the invention, when executed thereon.

Claim 1:
A method for soliciting a trigger-based, TB, physical layer protocol data unit, PPDU, transmission in a wireless local area network, WLAN, the method comprising:
receiving (<NUM>), by a station, STA, a trigger frame which is used to solicit a type of TB PPDU transmissions from a plurality of STAs in the WLAN, wherein the type of TB PPDU transmissions comprises high efficiency, HE, trigger-based, TB, PPDU transmissions, or extremely high throughput, EHT, TB PPDU transmissions, and one or two subfields in the trigger frame indicate a bandwidth, BW, of the solicited TB PPDU, and
transmitting (<NUM>), by the STA, the solicited TB PPDU in the BW indicated by the one or two subfields in the trigger frame;
wherein a common info field of the trigger frame comprises an uplink, UL, bandwidth, BW subfield indicating a BW of the solicited HE TB PPDU;
wherein the common info field of the trigger frame further comprises an enhanced trigger frame flag subfield which indicates whether the trigger frame is an <NUM>.11ax trigger frame or an enhanced trigger frame;
characterized in that when the enhanced trigger frame flag subfield indicates that the trigger frame is an enhanced trigger frame, both the UL BW subfield and a Delta EHT UL BW subfield indicate a BW of the solicited EHT TB PPDU;
wherein the UL BW subfield occupies <NUM> bits in the common info field of the trigger frame and the Delta EHT UL BW subfield occupies <NUM> bits of the enhanced trigger frame.