Physical layer protocol data unit format for inter-access point communication

Abstract

A first access point (AP) receives, from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU). The first PPDU indicates a first basic service set (BSS) color that does not match a BSS color of the first AP, a second BSS color different from the first BSS color, and a PPDU format, for the first PPDU, indicating an inter-BSS PPDU. Based on the PPDU format indicating the inter-BSS PPDU, the first AP determines whether the second BSS color matches the BSS color of the first AP. Based on the second BSS color matching the BSS color of the first AP, the first AP decodes a physical layer service data unit (PSDU) comprised in the first PPDU.

Description

Docket No.: 25-3001 PCTTITLEPhysical Layer Protocol Data Unit Format for Inter-Access Point Communication CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 743,737, filed January 10, 2025, U.S. Provisional Application No. 63 / 853,176, filed July 29, 2025, U.S. Provisional Application No. 63 / 854,010, filed July 30, 2025, and U.S. Provisional Application No. 63 / 854,869, filed July 31, 2025, all of which are hereby incorporated by reference in their entireties.BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Examples of several of the various embodiments of the present disclosure are described herein with reference to the drawings.

[0003] FIG. 1 illustrates example wireless communication networks in which embodiments of the present disclosure may be implemented.

[0004] FIG. 2 is a block diagram illustrating example implementations of a station (STA) and an access point (AP).

[0005] FIG. 3 illustrates a non-High Throughput (non-HT) Physical Layer Protocol Data Unit (PPDU), a High Throughput (HT) mixed PPDU, and a Very High Throughput (VHT) PPDU.

[0006] FIG. 4 illustrates a High Efficiency (HE) Single User (SU) PPDU, an HE Multi-User (MU) PPDU, and an HE Extended Range (ER) SU PPDU.

[0007] FIG. 5 illustrates an Extremely High Throughput (EHT) Multi-user (MU) PPDU.

[0008] FIG. 6 illustrates an Ultra-High Reliability (UHR) Multi-user (MU) PPDU.

[0009] FIG.7 illustrates an example Universal Signal field (U-SIG) which may be used in EHT Trigger Based (TB) PPDUs.

[0010] FIG. 8 illustrates an example UHR Signal field (UHR-SIG) content channel.

[0011] FIG. 9 illustrates an example U-SIG which may be used in UHR MU PPDUs.

[0012] FIG. 10 illustrates an example that highlights a potential problem that may arise in inter-AP communication.

[0013] FIG. 11 illustrates an example operation according to an embodiment.

[0014] FIG. 12 illustrates a further example operation according to an embodiment.

[0015] FIG. 13 illustrates an additional example operation according to an embodiment.

[0016] FIG. 14 illustrates another example operation according to an embodiment.

[0017] FIG. 15 illustrates an example U-SIG which may be used in UHR MU PPDUs, according to an embodiment

[0018] FIG. 16 illustrates an example process according to an embodiment.

[0019] FIG. 17 illustrates another example process according to an embodiment.Docket No.: 25-3001 PCTDETAILED DESCRIPTION

[0020] In the present disclosure, various embodiments are presented as examples of how the disclosed techniques may be implemented and / or how the disclosed techniques may be practiced in environments and scenarios. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the scope. After reading the description, it will be apparent to one skilled in the relevant art how to implement alternative embodiments. The present embodiments may not be limited by any of the described exemplary embodiments. The embodiments of the present disclosure will be described with reference to the accompanying drawings. Limitations, features, and / or elements from the disclosed example embodiments may be combined to create further embodiments within the scope of the disclosure. Any figures which highlight the functionality and advantages, are presented for example purposes only. The disclosed architecture is sufficiently flexible and configurable, such that it may be utilized in ways other than that shown. For example, the actions listed in any flowchart may be re-ordered or only optionally used in some embodiments.

[0021] Embodiments may be configured to operate as needed. The disclosed mechanism may be performed when certain criteria are met, for example, in a station, an access point, a radio environment, a network, a combination of the above, and / or the like. Example criteria may be based, at least in part, on for example, wireless device or network node configurations, traffic load, initial system set up, packet sizes, traffic characteristics, a combination of the above, and / or the like. When the one or more criteria are met, various example embodiments may be applied. Therefore, it may be possible to implement example embodiments that selectively implement disclosed protocols.

[0022] In this disclosure, "a” and "an” and similar phrases are to be interpreted as "at least one” and "one or more.” Similarly, any term that ends with the suffix “(s)” is to be interpreted as "at least one” and “one or more.” In this disclosure, the term “may” is to be interpreted as “may, for example.” In other words, the term “may” is indicative that the phrase following the term “may” is an example of one of a multitude of suitable possibilities that may, or may not, be employed by one or more of the various embodiments. The terms “comprises” and “consists of’, as used herein, enumerate one or more components of the element being described. The term “comprises” is interchangeable with “includes” and does not exclude unenumerated components from being included in the element being described. By contrast, “consists of’ provides a complete enumeration of the one or more components of the element being described. The term “based on”, as used herein, may be interpreted as “based at least in part on” rather than, for example, “based solely on”. The term “and / or” as used herein represents any possible combination of enumerated elements. For example, “A, B, and / or C” may represent A; B; C; A and B; A and C; B and C; or A, B, and C.

[0023] If A and B are sets and every element of A is an element of B, A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, possible subsets of B = {STA1 , STA2] are: {STA1}, {STA2}, and {STA1 , STA2}. The phrase “based on” (or equally “based at least on”) isDocket No.: 25-3001 PCTindicative that the phrase following the term “based on” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “in response to” (or equally “in response at least to”) is indicative that the phrase following the phrase “in response to” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “depending on” (or equally “depending at least to”) is indicative that the phrase following the phrase “depending on" is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “employing / using” (or equally “employing / using at least”) is indicative that the phrase following the phrase “employing / using” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments.

[0024] The term configured may relate to the capacity of a device whether the device is in an operational or non-operational state. Configured may refer to specific settings in a device that effect the operational characteristics of the device whether the device is in an operational or non-operational state. In other words, the hardware, software, firmware, registers, memory values, and / or the like may be “configured" within a device, whether the device is in an operational or nonoperational state, to provide the device with specific characteristics. Terms such as “a control message to cause in a device” may mean that a control message has parameters that may be used to configure specific characteristics or may be used to implement certain actions in the device, whether the device is in an operational or non-operational state.

[0025] In this disclosure, parameters (or equally called, fields, or Information elements: lEs) may comprise one or more information objects, and an information object may comprise one or more other objects. For example, if parameter (IE) N comprises parameter (IE) M, and parameter (IE) M comprises parameter (IE) K, and parameter (IE) K comprises parameter (information element) J. Then, for example, N comprises K, and N comprises J. In an example embodiment, when one or more messages / frames comprise a plurality of parameters, it implies that a parameter in the plurality of parameters is in at least one of the one or more messages / frames but does not have to be in each of the one or more messages / frames.

[0026] Many features presented are described as being optional through the use of “may” or the use of parentheses. For the sake of brevity and legibility, the present disclosure does not explicitly recite each and every permutation that may be obtained by choosing from the set of optional features. The present disclosure is to be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features may be embodied in seven ways, namely with just one of the three possible features, with any two of the three possible features or with three of the three possible features.

[0027] Many of the elements described in the disclosed embodiments may be implemented as modules. A module is defined here as an element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e.g., hardware with a biological element) or a combinationDocket No.: 25-3001 PCTthereof, which may be behaviorally equivalent. For example, modules may be implemented as a software routine written in a computer language configured to be executed by a hardware machine (such as C, C++, Fortran, Java, Basic, MatLab or the like) or a modeling / simulation program such as Simulink, Stateflow, GNU Octave, or LabVIEW MathScript. It may be possible to implement modules using physical hardware that incorporates discrete or programmable analog, digital and / or quantum hardware. Examples of programmable hardware comprise computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs); field programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs). Computers, microcontrollers, and microprocessors are programmed using languages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDs are often programmed using hardware description languages (HDL) such as VHSIC hardware description language (VHDL) or Verilog that configure connections between internal hardware modules with lesser functionality on a programmable device. The mentioned technologies are often used in combination to achieve the result of a functional module.

[0028] FIG. 1 illustrates example wireless communication network 100 in which embodiments of the present disclosure may be implemented. As shown in FIG. 1, the example wireless communication networks may include an Institute of Electrical and Electronic Engineers (IEEE) 802.11 (WLAN) infra-structure network 102. WLAN infra-structure network 102 may include one or more basic service sets (BSSs) 110 and 120 and a distribution system (DS) 130.

[0029] BSS 110-1 and 110-2 each includes a set of an access point (AP or AP STA) and at least one station (STA or non-AP STA). For example, BSS 110-1 includes an AP 104-1 and a STA 106-1 , and BSS 110-2 includes an AP 104-2 and STAs 106-2 and 106-3. The AP and the at least one STA in a BSS perform an association procedure to communicate with each other.

[0030] DS 130 may be configured to connect BSS 110-1 and BSS 110-2. As such, DS 130 may enable an extended service set (ESS) 150. Within ESS 150, APs 104-1 and 104-2 are connected via DS 130and may have the same service set identification (SSID).

[0031] WLAN infra-structure network 102 may be coupled to one or more external networks. For example, as shown in FIG. 1 , WLAN infra-structure network 102 may be connected to another network 108 (e.g., 802.X) via a portal 140. Portal 140 may function as a bridge connecting DS 130 of WLAN infra-structure network 102 with the other network 108.

[0032] The example wireless communication networks illustrated in FIG. 1 may further include one or more ad-hoc networks or independent BSSs (IBSSs). An ad-hoc network or IBSS is a network that includes a plurality of STAs that are within communication range of each other. The plurality of STAs are configured so that they may communicate with each other using direct peer-to-peer communication (e.g., not via an AP).

[0033] For example, in FIG. 1, STAs 106-4, 106-5, and 106-6 may be configured to form a first IBSS 112-1. Similarly, STAs 106-7 and 106-8 may be configured to form a second IBSS 112-2. Since an IBSS doesDocket No.: 25-3001 PCTnot include an AP, it does not include a centralized management entity. Rather, STAs within an IBSS are managed in a distributed manner. STAs forming an IBSS may be fixed or mobile.

[0034] A STA as a predetermined functional medium may include a medium access control (MAC) layer that complies with an IEEE 802.11 standard. A physical layer interface for a radio medium may be used among the APs and the non-AP stations (STAs). The STA may also be referred to using various other terms, including mobile terminal, wireless device, wireless transmit / receive unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, or user. For example, the term "user” may be used to denote a STA participating in uplink Multi-user Multiple Input, Multiple Output (MU MIMO) and / or uplink Orthogonal Frequency Division Multiple Access (OFDMA) transmission.

[0035] A physical layer (PHY) protocol data unit (PPDU) may be a composite structure that includes a PHY preamble and a payload in the form of a PLOP service data unit (PSDU). For example, the PSDU may include a PHY Convergence Protocol (PLCP) preamble and header and / or one or more MAC protocol data units (MPDUs). The information provided in the PHY preamble may be used by a receiving device to decode the subsequent data in the PSDU. In instances in which PPDUs are transmitted over a bonded channel (channel formed through channel bonding), the preamble fields may be duplicated and transmitted in each of the multiple component channels. The PHY preamble may include both a legacy portion (or "legacy preamble”) and a non-legacy portion (or "non-legacy preamble”). The legacy preamble may be used for packet detection, automatic gain control and channel estimation, among other uses. The legacy preamble also may generally be used to maintain compatibility with legacy devices. The format of, coding of, and information provided in the non-legacy portion of the preamble is based on the particular IEEE 802.11 protocol to be used to transmit the payload.

[0036] A frequency band may include one or more sub-bands or frequency channels. For example, PPDUs conforming to the IEEE 802.11n, 802.11ac, 802.11ax and / or 802.11be standard amendments may be transmitted over the 2.4 GHz, 5 GHz, and / or 6 GHz bands, each of which may be divided into multiple 20 MHz channels. The PPDUs may be transmitted over a physical channel having a minimum bandwidth of 20 MHz. Larger channels may be formed through channel bonding. For example, PPDUs may be transmitted over physical channels having bandwidths of 40 MHz, 80 MHz, 160 MHz, or 520 MHz by bonding together multiple 20 MHz channels.

[0037] FIG. 2 is a block diagram 200 illustrating example implementations of a STA 210 and an AP 260. As shown in FIG. 2, STA 210 may include at least one processor 220, a memory 230, and at least one transceiver 240. AP 260 may include at least one processor 270, a memory 280, and at least one transceiver 290. Processor 220 / 270 may be operatively connected to memory 230 / 280 and / or to transceiver 240 / 290.

[0038] Processor 220 / 270 may implement functions of the PHY layer, the MAC layer, and / or the logical link control (LLC) layer of the corresponding device (STA 210 or AP 260). Processor 220 / 270 may include one or more processors and / or one or more controllers. The one or more processors and / or one or moreDocket No.: 25-3001 PCTcontrollers may comprise, for example, a general-purpose processor, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a logic circuit, or a chipset, for example.

[0039] Memory 230 / 280 may include a read-only memory (ROM), a random-access memory (RAM), a flash memory, a memory card, a storage medium, and / or other storage unit. Memory 230 / 280 may comprise one or more non-transitory computer readable mediums. Memory 230 / 280 may store computer program instructions or code that may be executed by processor 220 / 270 to carry out one or more of the operations / embodiments discussed in the present application. Memory 230 / 280 may be implemented (or positioned) within processor 220 / 270 or external to processor 220 / 270. Memory 230 / 280 may be operatively connected to processor 220 / 270 via various means known in the art.

[0040] T ransceiver 240 / 290 may be configured to transmit / receive radio signals. In an example, transceiver 240 / 290 may implement a PHY layer of the corresponding device (STA 210 or AP 260). In an example, STA 210 and / or AP 260 may be a multi-link device (MLD), that is a device capable of operating over multiple links as defined by the IEEE 802.11 standard. As such, STA 210 and / or AP 260 may each implement multiple PHY layers. The multiple PHY layers may be implemented using one or more of transceivers 240 / 290.

[0041] FIG. 3 illustrates a non-High Throughput (non-HT) PPDU 310, a High Throughput (HT) mixed mode PPDU 320, and a Very High Throughput (VHT) PPDU 330.

[0042] Non-HT PPDU 310 may be used by STAs conforming to the IEEE 802.11a standard amendment. As shown in FIG. 3, non-HT PPDU 310 includes a non-HT Short Training field (L-STF), a non-HT Long Training field (L-LTF), a non-HT Signal field (L-SIG), and a Data field. The L-STF, L-LTF, and L-SIG form a 20 pis preamble of non-HT PPDU 310.

[0043] The L-STF may be used by a receiver of non-HT PPDU 310 to synchronize with the carrier frequency and frame timing of a transmitter of non-HT PPDU 310 and to adjust the receiver signal gain. The L-LTF may be used by the receiver of non-HT PPDU 310 to estimate channel coefficients in order to equalize the channel response (e.g., amplitude and phase distortion) in both the L-SIG and the Data fields of non-HT PPDU 310.

[0044] The L-SIG contains parameters needed to demodulate the Data field, which contains a payload of non-HT PPDU 310. The L-SIG may be equalized using the channel coefficients estimated using the L-LTF and demodulated to obtain the demodulation parameters of the Data field. The Data Field includes one or more symbols each having a duration of 4 pis, where 3.2 pis carry symbol information and 0.8 pis carry a Guard Interval (Gl)

[0045] For non-HT PPDUs, the only supported bandwidth is 20MHz, which is divided into 64 subcarriers. As such, non-HT PPDU 310 may be encoded using a subcarrier spacing of 20MHz / 64 or 312.5kHz.

[0046] HT mixed mode PPDU 320 may be used by STAs conforming to the IEEE 802.11n standard amendment. HT mixed mode PPDU 320 can support MIMO to up to 4 spatial streams, which enhancesDocket No.: 25-3001 PCTspectral efficiency four folds. HT mixed mode PPDU 320 has a minimum preamble duration of 35.6 pis, which may increase depending on the number of spatial streams carried by the PPDU.

[0047] As shown in FIG. 3, HT mixed mode PPDU 320 includes an L-STF, an L-LTF, an L-SIG, an HT Signal field (HT-SIG) field, an HT Short Training field (HT-STF) field, one or more HT Long Training field (HT-LTF), and a data field. The HT-LTF and data fields include of one or more symbols each having a duration of 3.6 pis or 4 pis. In both cases, 3.2 pis carry symbol information while the remaining 0.4 pis or 0.8 pis carry a Gl. The 0.4 pis long Gl is called short Gl while the 0.8 pis long Gl is called regular or normal Gl.

[0048] For HT mixed mode PPDUs, two bandwidths, 20 MHz and 140 MHz, may be supported. When the PPDU bandwidth is 20MHz, the band is divided into 64 subcarriers. When the PPDU bandwidth is 140 MHz, the band is divided into 128 subcarriers. In both cases, subcarrier spacing of 312.5 kHz is maintained.

[0049] VHT PPDU 330 may be used by STAs conforming to the IEEE 802.11ac standard amendment. VHT PPDU 330 can support MIMO transmission to up to 8 spatial streams, which enhances spectral efficiency eight folds. VHT PPDU 330 has a minimum preamble duration of 39.6 pis, which may increase depending on the number of spatial streams carried by VHT PPDU 330.

[0050] As shown in FIG. 3, VHT PPDU 330 includes an L-STF, an L-LTF, an L-SIG, a VHT Signal A field (VHT-SIG-A), a VHT Short Training field (VHT-STF), one or more VHT Long Training field (VHT-LTF), a VHT Signal B field (VHT-SIG-B), and a Data field. The VHT-LTF and Data fields of VHT PPDU 330 include one or more symbols each having a duration of 3.6 pis or 4 pis. In both cases, 3.2 pis carry symbol information while the remaining 0.4 pis or 0.8 pis carry of the Gl. The 0.4 pis long Gl is called the Short Gl while the 0.8pis long is called regular or normal Gl.

[0051] For VHT PPDUs, four bandwidths, 20 MHz, 40 MHz, 80 MHz, and 160 MHz, may be supported. When the PPDU bandwidth is 20MHz, the band is divided into 64 subcarriers. When the PPDU bandwidth is 40 MHz, the band is divided into 128 subcarriers. When the PPDU bandwidth is 80MHz, the band is divided into 256 subcarriers. When the PPDU bandwidth is 160 MHz, the band is divided into two 256-subcarrier 80MHz bands. In all cases, a subcarrier spacing of 312.5 kHz is maintained.

[0052] FIG. 4 illustrates a High Efficiency (HE) Single User (SU) PPDU 410, an HE Multi-User (MU) PPDU 420, and an HE Extended Range (ER) SU PPDU 430. HE SU PPDU 410, HE MU PPDU 420, and HE ER SU PPDU 430 may be used by STAs conforming to the IEEE 802.11ax standard amendment.

[0053] HE SU PPDU 410 supports higher spectral efficiency compared to VHT PPDU 330 due to increased subcarrier spacing and higherorder modulation support. HE SU PPDU 410 has a minimum preamble duration of 44 pis.

[0054] As shown in FIG. 4, HE SU PPDU 410 includes an L-STF, an L-LTF, an L-SIG, a Repeated L-SIG (RL-SIG), an HE Signal A field (HE-SIG-A), an HE Short Training field (HE-STF) field, one or more HE Long Training field (HE-LTF), a Data field, and a PE field.Docket No.: 25-3001 PCT

[0055] Similar to HE SU PPDU 410, HE MU PPDU 420 supports higher spectral efficiency compared to VHT PPDU 330. HE MU PPDU 420 also supports OFDMA. Due to denser subcarrier spacing (as in HE SU PPDU 410), HE MU PPDU 420 allows for payloads of multiple users to be multiplexed in the frequency domain in the Data field. HE MU PPDU 420 supports multiplexing the payload of up to 9 users in a single 20 MHz band. HE MU PPDU 420 has a minimum preamble duration of 47.2 pis, which may increase depending on the number of spatial streams carried by HE MU PPDU 420.

[0056] As shown in FIG. 4, HE MU PPDU 420 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, an HE-SIG-A, an HE Signal B Field (HE-SIG-B), an HE-STF field, one or more HE-LTF field, a Data field, and a PE field. It is noted that compared to HE SU PPDU 410, HE MU PPDU 420 further includes HE-SIG-B. HE-SIG-B contains indications per STA of RU allocations. A STA may use the indications in HE-SIG-B to locate its payload in HE MU PPDU 420.

[0057] For HE SU PPDU 410 and HE MU PPDU 420, the Gl portion of the HE-LTF and Data field may be one of one of 0.8 pis, 1.6 pis, and 3.2 pis. An AP or STA may use a suitable Gl duration depending on the channel conditions or capability of the target STA or AP.

[0058] For both HE SU PPDU 410 and HE MU PPDU 420, the information portion of the HE-LTF may be one of 3.2 pis, 6.4 pis, or 12.8 pis. Depending on the information portion duration, a subcarrier spacing of the HE-LTF may be one of: 312.5kHz if the information potion is 3.2 pis, 156.25kHz if the information portion is 6.4 pis, and 78.125kHz if the information portion is 12.8 pis. Unlike the HE-LTF, the information portion of the Data field for both HE SU PPDU 410 and HE MU PPDU 420 is always 12.8 pis. Hence, a subcarrier spacing of the Data field is always 78.125kHz corresponding to the duration of the information portion being 12.8 pis. When a 3.2 pis or 6.4 pis long HE-LTF is used by a transmitting STA to transmit HE SU PPDU 410 or HE MU PPDU 420, a receiving STA is required to interpolate the channel estimates to a subcarrier spacing resolution of 78.125kHz to match the subcarrier spacing of the Data field.

[0059] As shown in FIG. 4, HE ER SU PPDU 430 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, an HE-SIG-A, an HE-STF, one or more HE-LTF, a Data field, and a PE field. It is noted that compared to HE SU PPDU 410, HE ER SU PPDU 430 has an HE-SIG-A that is duplicated in the time domain (16 pis long instead of 8 pis long in HE SU PPDU 410). As such, both L-SIG (duplicated using RL-SIG) and HE-SIG-A are sent in duplicates, which allows a receiving STA to combine the two copies to increase the energy of the received signal. This results in an extended range of reception and increases transmission reliability between the transmitting STA and the receiving STA.

[0060] FIG. 5 illustrates an Extremely High Throughput (EHT) MU PPDU. EHT MU PPDU 510 supports OFDMA up to a bandwidth of 320MHz. EHT MU PPDU 510 can improve spectral efficiency due to support of a higher order modulation compared to other PPDUs (e.g., HE SU PPDU 410 and HE MU PPDU 420) while supporting the same number of spatial streams. EHT MU PPDU 510 has a minimum preamble duration of 47.2 pis, which may increase depending on the number of spatial streams carried by EHT MU PPDU 510.Docket No.: 25-3001 PCT

[0061] As shown in FIG. 5, EHT MU PPDU 510 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, a Universal Signal field (U-SIG), an EHT Signal field (EHT-SIG), an EHT Short Training Field (EHT-STF), one or more EHT Long Training fields (EHT-LTF), a Data field, and a PE field It is noted that according to the IEEE 802.11 be standard amendment, EHT MU PPDU 510 may be used by a transmitting STA for both SU and MU transmissions.

[0062] The U-SIG is intended to ensure forward compatibility of EHT MU PPDU 510. This means that any future PPDUs that are backward compatible to IEEE 802.11 be will contain the same U-SIG field and interpretation. Because of this, IEEE 802.11be STAs will be able to understand at least in part a PPDU developed in a future amendment.

[0063] The EHT-SIG contains indications per STA of resource unit (RU) allocations. A STA may use the indications in the EHT-SIG to locate its payload in EHT MU PPDU 510.

[0064] The Gl portion of the EHT-LTF and Data fields of EHT MU PPDU 510 may be one of: 0.8 s, 1.6 ps, or 3.2 ps. An AP or STA may use a suitable Gl duration depending on the channel conditions or capability of the target STA or AP.

[0065] The information portion of the EHT-LTF may be one of 3.2 ps, 6.4 ps, or 12.8 ps. Depending on the information portion duration, a subcarrier spacing of the EHT-LTF may be one of: 312.5kHz if the information potion is 3.2 ps, 156.25kHz if the information portion is 6.4 ps, or 78.125kHz if the information portion is 12.8 ps. The information portion of the Data field of EHT MU PPDU 510 is always 12.8 ps. Hence, a subcarrier spacing of the Data field is always 78.125kHz corresponding to the duration of the information portion being 12.8 ps. When a 3.2 ps long or a 6.4 ps long EHT-LTF is used by a transmitting STA to transmit EHT MU PPDU 510, a receiving STA is required to interpolate the channel estimates to a subcarrier spacing resolution of 78.125kHz to match the Data field subcarrier spacing.

[0066] FIG. 6 illustrates an Ultra-High Reliability (UHR) Multi-user (MU) PPDU. In an example, UHR MU PPDU 610 shares many similarities with EHT MU PPDU 510 illustrated in FIG. 5. For example, UHR MU PPDU 610 supports OFDMA up to a bandwidth of 320MHz, can improve spectral efficiency due to support of a higher order modulation compared to other PPDUs (e.g., HE SU PPDU 410 and HE MU PPDU 420) while supporting the same number of spatial streams, and has a minimum preamble duration of 47.2 pis, which may increase depending on the number of spatial streams carried by UHR MU PPDU 610.

[0067] Further, as shown in FIG. 6, and again like EHT MU PPDU 510 illustrated in FIG. 5, UHR MU PPDU 610 includes an L-STF, an L-LTF, an L-SIG, an RL-SIG, and a U-SIG field. In a example, UHR MU PPDU 610 includes a UHR Signal field (UHR -SIG), a UHR Short Training Field (UHR -STF), one or more UHR Long Training fields (UHR -LTF), a Data field, and a PE field. In an example, UHR MU PPDU 610 may be used by a transmitting STA for both SU and MU transmissions.

[0068] The U-SIG is intended to ensure forward and backward compatibility of UHR MU PPDU 610. This means that any future PPDUs that are backward compatible to IEEE 802.11 bn will contain the same U-SIGDocket No.: 25-3001 PCTfield and interpretation. Because of this, IEEE 802.11bn STAs will be able to understand at least in part a PPDU developed in a future amendment. Likewise, STAs developed prior to IEEE 802.11bn that are capable of transmitting and receiving PPDUs (e.g. EHT MU PPDUs) with a U-SIG field will be able to understand at least in part a UHR MU PPDU.

[0069] The UHR-SIG contains indications per STA of RU allocations. A STA may use the indications in the UHR-SIG to locate its payload in UHR MU PPDU 610.

[0070] FIG. 7 illustrates an example U-SIG field 700 which may be used in EHT TB PPDUs. As shown in FIG. 7, U-SIG field 700 includes two symbols, U-SIG- 1 and U-SIG-2, each containing 26 bits.

[0071] U-SIG field 700 is designed to bring forward compatibility to the EHT preamble via the introduction of version independent subfields. For the EHT PHY, version independent subfields are located in U-SIG- 1 only. Version independent subfields are subfields that are consistent in location and interpretation across various IEEE 802.11 PHY layers. The intent of version independent subfields is to achieve better coexistence among IEEE 802.11 PHYs that are defined for 2.4, 5, and 6 GHz spectrum from the EHT PHY specification onwards.

[0072] As shown in FIG. 7, U-SIG field 700 includes version independent subfields followed by version dependent subfields. The version independent subfields are located from bit B0 to B19 of U-SIG- 1 , while the version dependent subfields are located from bits B20 to B25 of U-SIG- 1 and over all the bits of U-SIG-2.

[0073] The PHY Version Identifier subfield is one of the version independent subfields in U-SIG field 700. The purpose of the PHY Version Identifier is to facilitate autodetection for IEEE 802.11 PHY layers that are defined for 2.4, 5, and 6 GHz spectrum from the EHT PHY specification onwards. The value of this subfield is used to identify the exact PHY version of the EHT PPDU.

[0074] Other version independent subfields include a Bandwidth (BW) subfield, which indicates the PPDU bandwidth, an Uplink / Downlink (UL / DL) subfield, which indicates whether the PPDU is an uplink or a downlink PPDU, a BSS Color subfield, which indicates the BSS Color of the PPDU, and a TXOP subfield, which indicates a duration of a transmit opportunity (TXOP) in which the PPDU is transmitted.

[0075] Version dependent subfields in U-SIG field 700 are subfields specific to an IEEE 802.11 PHY. For example, in FIG. 7, the version dependent subfields include a Disregard subfield in U-SIG- 1 and all the subfields in U-SIG-2. As shown in FIG. 7, U-SIG-2 may include a PPDU Type and Compressed Mode subfield, a Validate subfield, a Spatial Reuse 1 subfield, a Spatial Reuse 2 subfield, a Disregard subfield, a CRC subfield, and a Tail subfield.

[0076] Disregard subfields (e.g., bits B20 to B25 of U-SIG-1 and bits B11 to B15 of U-SIG-2) are intended for use by a future PHY Version that may not be supported by a receiving STA. A Receiving STA may ignore these subfields without impact on the STA’s continued reception of the PPDU (i.e. , reception at the STA can continue as usual after skipping these fields).Docket No.: 25-3001 PCT

[0077] The PPDU Type and Compressed Mode subfield indicates the type of PPDU among a number of PPDU types (e.g., EHT MU PPDU or EHT TB PPDU) supported by a particular PHY Version.

[0078] Validate subfields such as bit B2 in U-SIG-2 may indicate whether to continue or terminate the reception of a PPDU at a STA. If a STA encounters a PPDU where at least one field in the preamble that is identified as Validate for the STA is not set to the value specified for the field in that PHY version, the STA may terminate the reception of the PPDU. In this case, it waits until the PPDU’s estimated duration expires and report the information from the version independent subfields to the MAC layer. Similarly, the STA may terminate the reception of the PPDU when at least one field in the preamble equals a value that is identified as Validate for the STA.

[0079] Spatial Reuse subfields 1 and 2 may contain parameters to support spatial reuse features defined in a specific PHY version. Since these are version dependent subfields, only STAs supporting a specific PHY version are able to understand these bits.

[0080] The CRC subfield contains a frame check sum to validate the correctness of U-SIG field contents. The Tail subfield is set to 0 and is used to terminate the trellis of a convolutional encoder used to encode U-SIG fields.

[0081] FIG. 8 illustrates an example UHR-SIG content channel 800 for a UHR-SIG field of a UHR MU PPDU. In an example, a UHR-SIG field provides additional signaling to the U-SIG field for STAs to interpret a UHR MU PPDU. For example, in a UHR MU PPDU, the UHR-SIG field may contain U-SIG overflow bits that are common to all users. The UHR-SIG field may further contain resource allocation information to allow the STAs to look up the corresponding resources to be used in the UHR modulated fields of the PPDU. The integer fields of the UHR-SIG field may be transmitted in unsigned binary format, LSB first, where the LSB is in the lowest numbered bit position. In an example, UHR-SIG content channel 800 corresponds, in relevant part, to an EHT-SIG content channel for an EHT-SIG field of an EHT MU PPDU.

[0082] For example, the UHR-SIG field of a 20 MHz UHR MU PPDU may contain one UHR-SIG content channel. For OFDMA transmission and for non-OFDMA transmission to multiple users, the UHR-SIG field of a UHR MU PPDU that is 40 MHz or 80 MHz may contain two UHR-SIG content channels. For OFDMA transmission and for non-OFDMA transmission to multiple users, the UHR-SIG field of a UHR MU PPDU that is 160 MHz or wider may contain two UHR-SIG content channels per 80 MHz frequency subblock. The UHR-SIG content channels per 80 MHz frequency subblock may be allowed to carry different information when UHR MU PPDU bandwidth for OFDMA transmission is wider than 80 MHz. The UHR-SIG field of a UHR SU transmission or the UHR-SIG field of a UHR sounding NDP may contain one UHR-SIG content channel that is duplicated in each nonpunctured 20 MHz subchannel when the UHR PPDU is equal to or wider than 40 MHz.

[0083] In an example, UHR-SIG content channel 800 illustrates a UHR-SIG content channel for OFDMA transmission if bandwidth is equal to 20 / 40 / 80 MHz. As illustrated, UHR-SIG content channel 800 includes aDocket No.: 25-3001 PCTcommon field followed by a user specific field. For OFDMA transmission, the common field of a UHR-SIG content channel may contain information regarding resource unit allocation, such as the RU assignment to be used in the UHR modulated fields of the PPDU, the RUs allocated for MU-MIMO and the number of users in MU-MIMO allocations.

[0084] As illustrated, UHR-SIG content channel 800 further includes a user specific field. In an example, the user specific field includes zero or more user encoding blocks followed by padding (if present). For example, each nonfinal user encoding block may be made up of two user fields (e.g., User Field 1 and User Field 2) that contain information for two STAs that are used to decode their payloads. The final user encoding block may contain information for one or two users (e.g., User Field N), depending on the number of user fields in the UHR-SIG content channel.

[0085] A user field may include a STA-ID field. In an example, the STA-ID field may be set to a value of the TXVECTOR parameter STA-ID. In an example, if the PPDU is intended for an AP, STA-ID contains one element that is set to the association ID (AID) of the non-AP STA transmitting the PPDU. If the PPDU is intended for a non-AP STA, the STA-ID is set to the recipient of the PPDU. In MU PPDUs, there may be multiple STA-ID fields, i.e. one for each recipient.

[0086] A user field may further include a modulation and coding scheme (MCS) field. In an example, if the STA-ID field is not equal to 2046, the MCS field indicates an MCS set to n, where n = 0, 1, . . . , 15. If the STA-ID field is equal to 2046, the MCS may be set to an arbitrary value.

[0087] The user field may further include a reserved field. This field may be reserved and set to 1.

[0088] The user field may further include a number of spatial streams (NSS) field. In an example, if the STAID field is not equal to 2046, the NSS field indicates the number of spatial streams for up to eight spatial streams. The NSS field may be set to the number of spatial streams minus 1 . The NSS field may be set to an arbitrary value if the STA-ID field is equal to 2046.

[0089] The user field may further include a beamformed field. In an example, if the STA-ID subfield is not 2046, the beamformed subfield is used to indicate transmit beamforming. For example, the beamformed field may be set to 1 if a beamforming steering matrix is applied to the waveform in a non-MU-MIMO allocation. The beamformed field may be set to 0 otherwise. Further, the beamformed field may be set to an arbitrary value if the STA-ID subfield is 2046.

[0090] The user field may further include a coding field. In an example, if the STA-ID field is not equal to 2046, the coding field indicates whether binary convolutional coding (BCC) or low density parity check (LDPC) is used. For example, the coding field may be set to 0 for BCC, and may be set to 1 for LDPC. Further, the coding field may be set to an arbitrary value if the STA-ID subfield is 2046.

[0091] FIG. 9 illustrates an example Universal Signal (U-SIG) field 900 which may be used in UHR MU PPDUs. As shown in FIG. 9, U-SIG field 900 includes two symbols, U-SIG- 1 and U-SIG-2, each containing 26 bits. In an example, like U-SIG field 700 illustrated in FIG. 5 for EHT MU PPDUs, U-SIG field 900 includesDocket No.: 25-3001 PCTversion independent subfields followed by version dependent subfields. The version independent subfields are located from bit BO to B19 of U-SIG-1, while the version dependent subfields are located from bits B20 to B25 of U-SIG-1 and over all the bits of U-SIG-2.

[0092] The PHY Version Identifier subfield is one of the version independent subfields in U-SIG field 900. The purpose of the PHY Version Identifier is to facilitate autodetection for IEEE 802.11 PHY layers that are defined for 2.4, 5, and 6 GHz spectrum from the EHT PHY specification onwards. The value of this subfield is used to identify the exact PHY version of the PPDU. For example, the PHY Version Identifier may be set to 1 to indicate UHR (e.g., as opposed to 0 to indicate EHT).

[0093] Other version independent subfields include a Bandwidth (BW) subfield, which indicates the PPDU bandwidth, an Uplink / Downlink (UL / DL) subfield, which indicates whether the PPDU is an uplink or a downlink PPDU, a first BSS Color subfield, which indicates the BSS Color of the PPDU, and a TXOP subfield, which indicates a duration of a transmit opportunity (TXOP) in which the PPDU is transmitted.

[0094] Version dependent subfields in U-SIG field 900 are subfields specific to an IEEE 802.11 PHY. For example, in FIG. 9, the version dependent subfields include bits B20-B25. In an example, UHR may define a variant UHR MU PPDU for coordinated beamforming (Co-BF) and coordinated spatial reuse (Co-SR). In this case, a second BSS Color field may be defined to signal the BSS Color of a shared AP. The second BSS color may be used by the recipient STA of the Co-BF / Co-SR to decode their respective payloads. Where Co-BF or Co-SR is used, bits B20-B25 may indicate this second BSS color. Where neither Co-BF nor Co-SR is used, bits B20-B25 may use the same definition as U-SIG field 700 for an EHT MU PPDU (e.g., bits B20-B24 may be disregard bits and bit B25 may be a validate bit).

[0095] As shown in FIG. 9, the U-SIG-2 may include a PPDU Type and Compression Mode field, similar to U-SIG field 700 illustrated in FIG. 7. Further, U-SIG-2 may include a Co-BF / Co-SR indication field. In an example, the Co-BF / Co-SR indication field indicates whether Co-SR is on, or off, in SU transmission, indicates whether Co-BF is on, or off, in non-OFDMA MU-MIMO, and is a validate bit in other cases. For example, a receiving STA may use the Co-BF / Co-SR indication field to identify whether B20-B25 in U-SIG-1 indicates a second BSS color. Where the Co-BF / Co-SR indication field is high, the receiving STA can identify the second BSS color for Co-BF / Co-SR using B20-B25 in U-SIG-1.

[0096] In an example, the U-SIG-2 may further include a punctured channel information field, a validate bit, a UHR-SIG MCS field, a CRC field, and a tail field. The punctured channel information field may include a puncturing pattern indicating that the PPDU avoids transmissions in certain subcarriers. The validate field may be set to 1 and may be treated as a validate field. This means that a UHR STA may be configured not to continue reception of a UHR MU PPDU if the validate field indicates a value of 0. The UHR-SIG MCS field may indicate the MCS used for modulation of the UHR-SIG field of the UHR MU PPDU. The CRC field may contain a frame check sum to validate the correctness of U-SIG field contents. The tail subfield may be set to 0 and may be used to terminate the trellis of a convolutional encoder used to encode U-SIG fields.Docket No.: 25-3001 PCT

[0097] FIG. 10 illustrates an example 1000 that highlights a potential problem that may arise in inter-AP communication. Example 1000 includes APs 1002 and 1004. In an example, APs 1002 and 1004 operate according to the IEEE 802.11bn amendment and may be referred to as UHR APs. AP 1002 and AP 1004 may undertake inter-AP coordination for a variety of UHR features, including Co-BF, Co-SR, coordinated restricted target wake time (r-TWT) operation, and seamless roaming. This inter-AP coordination may require AP 1002 and AP 1004 to exchange management frames (e.g., an r-TWT schedule, a buffer status report (BSR), and other suitable management frames). For example, AP 1002 may solicit and receive feedback from AP 1004. AP 1002 may also provide unsolicited feedback to AP 1004.

[0098] As illustrated, AP 1002 transmits a feedback request frame 1012. For example, feedback request frame 1012 may be a trigger frame (TF) transmitted using a non-HT PPDU (e.g., non-HT PPDU 310 illustrated in FIG. 3). In an example, AP 1002 and 1004 may each receive, and decode, non-HT PPDUs transmitted by another AP. Thus, AP 1004 may receive, and decode, feedback request frame 1012 because AP 1002 transmits feedback request frame 1012 using a non-HT PPDU.

[0099] AP 1004 may respond by transmitting a feedback response frame 1014. For example, feedback response frame 1014 may be a TB PPDU. AP 1002 and AP 1004 may each also receive, and decode, TB PPDUs transmitted by another AP. Thus, AP 1002 may receive, and decode, feedback response frame 1014 because AP 1004 transmits feedback response frame 1014 using a TB PPDU.

[0100] In an example, AP 1002 may then transmit an unsolicited feedback frame 1022. For example, unsolicited feedback frame 1022 may include data transmitted using a non-HT PPDU. AP 1004 may receive, and decode, unsolicited feedback frame 1022 because, like feedback request frame 1012, AP 1002 transmits unsolicited feedback frame 1022 using a non-HT PPDU.

[0101] AP 1002 may then transmit another unsolicited feedback frame 1024. Unsolicited feedback frame 1024 may include data transmitted using a UHR MU PPDU (e.g., UHR MU PPDU 610 illustrated in FIG. 6, above). In an example, however, AP 1002 and AP 1004 may not receive, and decode, a UHR (or EHT or HE) PPDU, because of inconsistent parameter settings. For example, inconsistencies in BSS color, UL / DL flag, and / or STA-ID, in UHR / EHT / HE PPDUs transmitted from one AP to another AP, may cause the recipient AP to filter the PPDU. Thus, AP 1004 may filter unsolicited feedback frame 1024, and may not receive and decode unsolicited feedback frame 1024.

[0102] Transmission of unsolicited feedback from oneAPto another AP may, therefore, be limited to non-HT PPDUs. But non-HT PPDUs are severely bandwidth limited (e.g., limited to 20 MHz) compared with UHR / EHT / HE PPDUS, and may also be spatial stream limited (e.g., limited to a single spatial stream). This can lead to significant inefficiencies in inter-AP communication and negative impacts on communication performance.

[0103] Embodiments of the present disclosure, as further described below, address the above-described problem associated with existing technologies. In an aspect, a first AP receives, from a second AP, a firstDocket No.: 25-3001 PCTPPDU indicating: a first basic service set (BSS) color that does not match a BSS color of the first AP, a second BSS color different from the first BSS color, and a PPDU format, for the first PPDU, indicating an inter-BSS PPDU. Based on the PPDU format indicating the inter-BSS PPDU, the first AP determines whether the second BSS color matches the BSS color of the first AP. Based on the second BSS color matching the BSS color of the first AP, the first AP decodes a physical layer service data unit (PSDU) comprised in the first PPDU. As described further below, this may improve performance by allowing for the use of more advanced PPDUs for inter-AP communication.

[0104] In another aspect, a AP transmits, to a second AP, a first PPDU. The first PPDU may indicate a first basic service set (BSS) color. The first BSS color may not match a BSS color of the second AP. The first PPDU may further indicate a second BSS color. The second BSS color may be different from the first BSS color. The first PPDU may further indicate a PPDU format, for the first PPDU. The PPDU format may indicate an inter-BSS PPDU. Based on the PPDU format indicating an inter-BSS PPDU, the second AP may be configured to determine whether the second BSS color matches the BSS color of the second AP. Based on the second BSS color matching the BSS color of the second AP, the second AP may be configured to decode a physical layer service data unit (PSDU) comprised in the first PPDU.

[0105] In another aspect, a first AP may receive, from a second AP, a first PPDU. The first PPDU may indicate a value in an uplink (UL)Zdownlink (DL) field. The first PPDU may further indicate a PPDU format for the first PPDU. The first AP may determine whether to filter out the first PPDU based on one or more of: (i) the PPDU format, (ii) the value indicated in the UL / DL field, and (Hi) whether the second AP is a transmit opportunity (TXOP) owner. In an embodiment, the determining whether to filter out the first PPDU may be based on all of: (I) the PPDU format, (ii) the value indicated in the UL / DL field, and (iii) whether the second AP is the TXOP owner

[0106] In another aspect, a first AP may receive, from a second AP, a first PPDU. The first PPDU may indicate a station identifier (STAJD). The first PPDU may further indicate a PPDU format for the first PPDU. The first AP may determine whether to filter out the first PPDU based on one or more of: (i) the PPDU format, (ii) the STA_ID, and (iii) whether the first AP is a transmit opportunity (TXOP) owner. In an embodiment, the determining whether to filter out the first PPDU may be based on all of: (I) the PPDU format, (ii) the STA_ID, and (iii) whether the first AP is the TXOP owner. In an embodiment, the determining whether to filter out the first PPDU may be further based on whether the second AP has an assigned AP identifier (AP ID) by the first AP.

[0107] In another aspect, a first AP may receive, from a second AP, a first PPDU. The first PPDU may indicate a PPDU format for the first PPDU. The first PPDU may further indicate a value in an uplink (UL)Zdownlink (DL) field. The first PPDU may further indicate a station identifier (STAJD). The first PPDU may further indicate a first identifier indicating a first basic service set (BSS) color. The first AP may determine whether to filter out the first PPDU based on one or more of: (i) the PPDU format, (ii) the value indicated inDocket No.: 25-3001 PCTthe UL / DL field, (ill) the STAJ D, (iv) the first identifier, and (v) whether the first AP or the second AP is a transmit opportunity (TXOP) owner. In an embodiment, the determining whether to filter out the first PPDU may be based on all of: (I) the PPDU format, (II) the value indicated in the UL / DL field, (ill) the STAJ D, (iv) the first identifier, and (v) whether the first AP or the second AP is the TXOP owner.

[0108] FIG. 11 illustrates an example 1100 of an example operation according to an embodiment. Example 1100 includes APs 1102, 1104, and 1106. Example 1100 further includes STAs 1112 and 1114. In an embodiment, STA 1112 is associated with AP 1102, and AP 1102 and STA 1112 are members of a same BSS. For example, AP 1102 and STA 1112 may be members of a BSS with a BSS color equal to 1. Further, in an embodiment, STA 1114 is associated with AP 1104, and STA 1114 and AP 1104 are members of a BSS with a BSS color equal to 2. In an embodiment, AP 1106 is a member of another BSS, with a BSS color equal to 3.

[0109] As illustrated AP 1102 transmits a PPDU 1122 to AP 1104. For example, PPDU 1122 may be a UHR PPDU (e.g., UHR MU PPDU 610 illustrated in FIG. 6). In an embodiment, AP 1102 may set the BSS color of PPDU 1122 based on the owner of the TXOP (e.g., the owner of the TXOP in which PPDU 1122 is transmitted). In an example, a TXOP owner AP may be referred to as a sharing AP, and a TXOP responder AP may be referred to as a shared AP. As illustrated in FIG. 11 , for example, the BSS color of PPDU 1122 may be set to the BSS color of AP 1102 based on AP 1102 being the TXOP owner / sharing AP and AP 1104 being the TXOP responder / shared AP. Otherwise (e.g., if AP 1102 were not the TXOP owner / sharing AP), the BSS color of PPDU 1122 may be set to the BSS color of the intended AP (e.g., AP 1104). Additionally, AP 1102 and AP 1104 may negotiate (e.g., by exchanging one or more frames) an AP ID for each other (e.g , AP 1102 may assign an AP ID for AP 1104 and vice versa). In an example, AP 1102 and AP 1104 may perform this negotiation as part of establishing a multi-AP coordination (MAPC) agreement. In an embodiment, AP 1102 may set the BSS color of PPDU 1122 to the BSS color of the TXOP owner (e.g., the BSS color of AP 1102) if AP 1102 and AP 1104 have an established MAPC agreement. Otherwise, AP 1102 may set the BSS color of PPDU 1122 to a predefined value (e.g., 0, 2045, 2046, or 2047).

[0110] Further, in an embodiment, AP 1102 may set the BSS color of PPDU 1122 to the BSS color of the receiving AP 1104: BSS color=2. In an embodiment, the BSS color of PPDU 1122 being set to the BSS color of the receiving AP 1104 is based on PPDU 1122 containing a unicast frame addressed to AP 1104. For example, as illustrated in FIG. 9, a UHR PPDU may include a U-SIG (e.g., example U-SIG field 900) with a BSS color field in the version independent subfields (e.g., B7-B12 of U-SIG- 1 in U-SIG field 900). AP 1102 may set this BSS color field in PPDU 1122 to a value of 2, matching the BSS color of receiving AP 1104.

[0111] In an embodiment, AP 1102 may set a UL / DL field (e.g., B6 of U-SIG- 1 in U-SIG field 900) of PPDU 1122 based on whether AP 1102 is a TXOP owner (e.g., whether AP 1102 is the owner of the TXOP in which PPDU 1122 is transmitted). For example, AP 1102 may set the UL / DL field of PPDU 1122 to indicate DL transmission (e.g., to a value of 0) if AP 1102 is the TXOP owner. AP 1102 may instead set the UL / DL fieldDocket No.: 25-3001 PCTof PPDU 1122 to indicate UL transmission (e.g., to a value of 1) of PPDU 1122 addressed to an AP, if AP 1102 is the TXOP responder. In another embodiment, AP 1102 may set the UL / DL field of PPDU 1122 to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1) (e.g., regardless of whether AP 1102 is the TXOP owner).

[0112] In an embodiment, PPDU 1122 is transmitted by AP 1102 and intended for one or more APs (e.g., AP 1104). The TXVECTOR parameter UPLINK_FLAG may be set to 0 if the transmitting AP (e.g., AP 1102) is a TXOP owner, and 1 otherwise. The TXVECTOR parameter BSS_Color may be set to the BSS color of the TXOP owner if the transmitting AP (e.g., AP 1102) and recipient AP (e.g., AP 1104) have an established MAPC agreement, and 0 otherwise.

[0113] In an embodiment, setting the BSS color field to the receiving AP BSS color (e.g., 2) and setting the UL / DL field to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1) may allow AP 1104 to receive, and decode, the PPDU 1122, because receiving AP 1104 may think PPDU 1122 is transmitted to AP 1104 by an associated STA in its same BSS (e.g., STA 1114). In an embodiment, this may also be true if PPDU 1122 is an HE PPDU or an EHT PPDU: in all three examples (e.g., an HE PPDU, an EHT PPDU, or a UHR PPDU), AP 1102 may set the BSS color of PPDU 1122 to the recipient AP BSS color and the UL / DL field to indicate UL to an AP, allowing AP 1104 to receive, and decode, PPDU 1122. In the case of an HE PPDU (e.g. HE SU PPDU 410, HE MU PPDU 420, HE ER SU PPDU) which doesn’t include a U-SIG field, the UL / DL field and BSS color field may be indicated in the HE-SIG-A field.

[0114] For example, AP 1102 transmits PPDU 1122 with BSS color set to 2 and UL / DL set to 1. As discussed above, AP 1104 receives and decodes PPDU 1122. In an embodiment, AP 1104 transmits a BA 1124 in response.

[0115] But none of STA 1112, STA 1114, or AP 1106 receives and decodes PPDU 1122. For example, STA 1112 may not decode PPDU 1122 (e.g., STA 1112 may perform early receive termination) due to the UL / DL field being set to 1 (e.g., indicating transmission to an AP). STA 1114 may not decode PPDU 1122 (e.g., STA 1114 also may perform early receive termination) due to the UL / DL field being set to 1. AP 1106 may not decode PPDU 1122 (e.g., AP 1106 may perform early receive termination) due to the BSS color being set to 2, rather than AP 1106' s BSS color of 3.

[0116] In an embodiment, setting the BSS color of PPDU 1122 to 2 and the UL / DL field to 1 may not allow AP 1104 to differentiate PPDU 1122 from UL PPDUs transmitted by STAs associated with AP 1104 (e.g., UL PPDUs transmitted by STA 1114) The ability to differentiate between PPDUs may be critical in case PPDU 1122 is received in error, in which case AP 1104 may trigger the appropriate device for retransmission. To allow differentiation, AP 1102 may include in PPDU 1122 its own BSS color (e.g., BSS color=1). For example, if PPDU 1122 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a second BSS color field (e.g., B20-B25 of U-SIG- 1 in U-SIG field 900 illustrated in FIG. 9) to BSS color 1. If PPDU 1122 doesDocket No.: 25-3001 PCTnot indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a STA-ID field (e.g., the STAID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to BSS color 1.

[0117] Alternatively, or in addition, AP 1102 may differentiate PPDU 1122 from UL PPDUs transmitted by STAs associated with AP 1104 by including in PPDU 1122 an APJD for AP 1102. For example, prior to transmission of PPDU 1122, AP 1102 and AP 1104 may negotiate an APJD for AP 1102 (e.g., by exchanging one or more frames). If PPDU 1122 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the second BSS color field (e.g., B20-B25 of U-SIG-1 in U-SIG field 900 illustrated in FIG. 9) to the negotiated AP_ID (or a portion of the bits of the negotiated APJD) for AP 1102. If PPDU 1122 does not indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the STA-ID field (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to the negotiated AP_ID for AP 1102.

[0118] In an embodiment, AP 1102 may set a STA-ID field of PPDU 1122 based on the TXOP owner (e.g., the owner of the TXOP / sharing AP) during which PPDU 1122 is transmitted. In an embodiment, AP 1102 may set a STA-ID of PPDU 1122 further based on whether AP 1102 and AP 1104 have an established MAPC agreement and / or whether AP 1102 has an assigned APJD by AP 1104 (or vice versa). For example, where AP 1102 has an assigned APJD by AP 1104 and / or AP 1102 and AP 1104 have an established MAPC agreement, AP 1102 may set the STA-ID field of PPDU 1122 to the AP_I D of the recipient AP (e.g., AP 1104) if AP 1102 is the TXOP owner, and AP 1102 may set the STA-ID field of PPDU 1122 to the AP_ID of the transmitting AP (e.g., AP 1102) if AP 1102 is the TXOP responder (e.g., AP 1102 is not the TXOP owner for the TXOP during which PPDU 1122 is transmitted). That is, in an embodiment, the STA-ID of PPDU 1122 may be set to an AP I D of the transmitting AP (e.g ., AP 1102), if the intended AP (e.g., AP 1104) is the TXOP owner, and if the transmitting AP (e.g., AP 1102) has an assigned APJD by the intended AP (e.g , AP 1104). Otherwise, the STA-ID of PPDU 1122 may be set to a predetermined value (e.g., 2045). For example, in an embodiment, if AP 1102 and AP 1104 do not have an established MAPC agreement (and / or if AP 1102 does not have an APJD assigned by AP 1104), AP 1102 may set the STA-ID field to a predetermined value (e.g., a disregard value of 2045, or another value such as 0, 2046, or 2047). Thus, in an HE / EHT / UHR MU PPDU transmitted by an AP and intended for one recipient AP in which the transmitting AP has an established MAPC agreement, the TXVECTOR parameter STAJD may be set to the AP ID of the recipient AP if the transmitting AP is a TXOP owner, and set to the AP ID of the transmitting AP if the transmitting AP is a TXOP responder. If the transmitting AP and recipient AP do not have an established MAPC agreement, the STAJD may be set to 2045. Alternatively, or in addition, a STAJD (e.g., for an EHT / UHR MU PPDU) may set to an AP IDofthe transmitting AP, ifthe intended AP is the TXOP owner, and if the transmitting AP has an assigned AP ID by the intended AP. Otherwise, the STAJD may be set to 2045.

[0119] In an embodiment, if the STA-ID field of PPDU 1122 is not used to identify the transmitting AP BSS color, or to identify the negotiated AP_ID, the STA-ID may be set to a disregard value (e.g., 2045).Docket No.: 25-3001 PCT

[0120] Alternatively, or in addition, AP 1102 may indicate in PPDU 1122 a PPDU format (e.g., an inter-AP PPDU format). For example, AP 1102 may set a flag (e.g., a field made up of one or more bits) indicating that PPDU 1122 is an inter-AP PPDU, transmitted by one AP (e.g., AP 1102) to another AP (e g., AP 1104). In an embodiment, this indication may allow AP 1104 to identify PPDU 1122 as a PPDU from another AP, quickly and robustly, even where a data field is corrupted or where there is a collision of AP_ID and / or BSS color. For example, based on the indication (e.g., based on a flag in PPDU 1122), AP 1104 may set an intra-BSS NAV or an inter-BSS, even where a MAC header in PPDU 1122 is not available.

[0121] In an embodiment (not shown in the FIG. 11), AP 1102 transmits a PPDU 1122 to AP 1104 and AP 1106. For example, PPDU 1122 may be a UHR PPDU (e.g., UHR MU PPDU 610 illustrated in FIG. 6). In an embodiment, AP 1102 may set the BSS color of PPDU 1122 to a predefined / broadcast / multi-cast / MU BSS color. In an embodiment, the predefined / broadcast / mu Iti-cast / M U BSS color may be one of 0, 2045, 2046, or 2047. In another embodiment, the predefined / broadcast / multi-cast / MU BSS color may be negotiated by AP 1102, AP 1104, and AP 1106 (e.g., prior to any inter-AP communications). In an example, a negotiated predefined / broadcast / multi-cast / MU BSS color may relate to a group ID for a group of APs. For example, the negotiated predefined / broadcast / multi-cast / MU BSS color may be the group ID for a group of APs that includes AP 1102, AP 1104, and AP 1106 as members. In an embodiment, the BSS color of PPDU 1122 being set to the predefined / broadcast / multi-cast / MU BSS color is based on PPDU 1122 containing a multicast frame addressed to AP 1104 and AP 1106. In another embodiment, the BSS color of PPDU 1122 being set to the predefined / broadcast / multi-cast / MU BSS color is based on PPDU 1122 carrying one or more PSDUs for one or more APs (e.g., AP 1104 and AP 1106).

[0122] Further, in an embodiment, AP 1102 may set a UL / DL field (e.g., B6 of U-SIG- 1 in U-SIG field 900 illustrated in FIG. 9) of PPDU 1122 to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1). In an embodiment, setting the BSS color field to the predefined / broadcast / multi-cast / MU BSS color (e.g., 0, 2045, 2046, or 2047) and setting the UL / DL field to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1) may allow AP 1104 and AP 1106 to receive, and decode, the PPDU 1122, because receiving AP 1104 and AP 1106 may each think PPDU 1122 is transmitted by a respective associated STA in its same BSS (e.g., STA 1114 for AP 1104). In an embodiment, this may also be true if PPDU 1122 is an HE PPDU or an EHT PPDU: in all three examples (e.g., an HE PPDU, an EHT PPDU, or a UHR PPDU), AP 1102 may set the BSS color of PPDU 1122 to the predefined / broadcast / multi-cast / MU BSS color and the UL / DL field to indicate UL to an AP, allowing AP 1104 and AP 1106 to receive, and decode, PPDU 1122. In the case of an HE PPDU (e.g. HE SU PPDU 410, HE MU PPDU 420, or HE ER SU PPDU 430 illustrated in FIG. 4) which does not include a U-SIG field, the UL / DL field and BSS color field may be indicated in the HE-SIG-A field.

[0123] For example, AP 1102 may transmit PPDU 1122 with a BSS color set to the predefined / broadcast / multi-cast / MU BSS color and a UL / DL field set to 1 . As discussed above, AP 1104 mayDocket No.: 25-3001 PCTreceive and decode PPDU 1122. In an embodiment, AP 1104 may transmit a BA 1124 in response to PPDU 1122. Similarly, AP 1106 may receive and decodes PPDU 1122. In an embodiment, AP 1106 may transmit a BA frame (not shown) in response to PPDU 1122.

[0124] In an embodiment, none of STA 1112 or STA 1114 receives and decodes PPDU 1122. For example, STA 1112 may not decode PPDU 1122 (e.g., STA 1112 may perform early receive termination) due to the UL / DL field of PPDU 1122 being set to 1 (e.g., indicating transmission to an AP). As another example, STA 1114 may not decode PPDU 1122 (e.g., STA 1114 also may perform early receive termination) due to the UL / DL field being set to 1.

[0125] In an example, the BSS color of PPDU 1122 may be set to 2 and the UL / DL field may be set to 1 . In an example, setting the BSS color of PPDU 1122 to 2 and the UL / DL field to 1 may not allow AP 1104 or AP 1106 to differentiate PPDU 1122 from UL PPDUs transmitted by non-AP STAs (e.g., non-AP STAs associated with AP 1102, AP 1104, and AP 1106). The ability to differentiate between PPDUs may be critical in case PPDU 1122 is received in error, in which case, AP 1102, AP 1104 and / or AP 1106 may trigger the appropriate device for retransmission. To allow differentiation, AP 1102 may include in PPDU 1122 the BSS colors of AP 1104 (e.g., BSS color=2) and AP 1106 (e.g., BSS color=3). For example, when PPDU 1122 contains two or more STA-ID fields (e.g., PPDU 1122 carries two or more PSDUs for two or more APs), AP 1102 may set a STA-ID field for AP 1104 (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to BSS color 2 and a STA-ID field for AP 1106 (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to BSS color 3. In another example, when PPDU 1122 contains one STA-ID field (e.g., PPDU 1122 carries ones PSDU addressed to two or more APs), AP 1102 may set a STA-ID field to a predefined / broadcast / multi-cast / MU BSS color value.

[0126] Alternatively, or in addition, AP 1102 may differentiate PPDU 1122 from UL PPDUs transmitted by any non-AP STAs (e.g., associated with AP 1102, AP 1104, and AP 1106) by including in PPDU 1122 respective APJDs for AP 1104 and AP 1106. For example, prior to transmission of PPDU 1122, AP 1102, AP 1104, and AP 1106 may negotiate an AP_ID for AP 1102, AP 1104, and / or AP 1106 (e.g., by exchanging one or more frames). For example, when PPDU 1122 contains two or more STA-ID fields (e.g., PPDU 1122 carries two or more PSDUs for two or more APs), AP 1102 may set a STA-ID field for AP 1104 (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to the APJD of AP 1104 and a STA-ID field for AP 1106 (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG.8) to the APJD of AP 1106. In another example, when PPDU 1122 contains one STA-ID field (e.g., PPDU 1122 carries one PSDU addressed to two or more APs), AP 1102 may set a STA-ID field to a predefined / broadcast / multi-cast / MU AP_I D value (e.g., 0, 2045, 2046, or 2047).

[0127] In an embodiment, where PPDU 1122 is intended for two or more recipients, AP 1102 may set each STA-ID field of PPDU 1122 to identify the AP or group of APs that is the recipient of an RU in PPDU 1122. For example, for an individually addressed RU, AP 1102 may set the STA-ID field to the APJD of theDocket No.: 25-3001 PCTreceiving AP (e.g., AP 1104 or AP 1106, respectively), if the receiving AP has an established MAPC agreement with the transmitting AP (e.g., AP 1102). Otherwise, AP 1102 may set the STA-ID field to a predetermined value (e.g., a disregard value of 2045, or another value such as 0, 2046, or 2047). For an RU intended for multiple APs, AP 1102 may set the STA-ID field to one predetermined value (e.g., 0) if AP 1102 and the receiving AP (e.g., AP 1104 and / or AP 1106) have an established MAPC agreement, and, otherwise, to a different predetermined value (e.g., a disregard value of 2045). Thus, in an HE / EHT / UHR MU PPDU transmitted by an AP and intended for two or more recipients, each parameter STA_I D of the TXVECTOR may identify the AP or group of APs that is the recipient of an RU in the HE / EHT / UHR MU PPDU. For an individually addressed RU, the parameter STAJD may beset to the AP_I D of the receiving AP if the receiving AP has an established MAPC agreement with the transmitting AP, and 2045 otherwise. If an RU is intended for multiple APs, the parameter STAJD may be set to 0 if the transmitting AP and the receiving AP has an established MAPC agreement, and 2045 otherwise.

[0128] As discussed above, one or more of these improvements discussed for example 1100 may allow for the use of more advanced PPDUs (e.g., UHR / EHT / HE PPDUs) for inter-AP communication, improving communication performance.

[0129] FIG. 12 illustrates an example 1200 of a further example operation according to an embodiment. Example 1200 includes APs 1102, 1104, and 1106. Example 1200 further includes STAs 1112 and 1114. In an embodiment, APs 1102, 1104, and 1106, and STAs 1112 and 1114, described in example 1200 correspond to APs 1102, 1104, and 1106, and STAs 1112 and 1114, described in example 1100 illustrated in FIG. 11.

[0130] As illustrated AP 1102 transmits a PPDU 1222 to AP 1104. For example, PPDU 1222 may be a UHR PPDU (e.g., UHR MU PPDU 610 illustrated in FIG. 6). In an embodiment, AP 1102 may set the BSS color of PPDU 1222 to a broadcast value (e.g., 0). For example, as illustrated in FIG. 9, a UHR PPDU may include a U-SIG (e.g., example U-SIG field 900) with a BSS color field in the version independent subfields (e.g., B7-B12 of U-SIG-1 in U-SIG field 900). AP 1102 may set this BSS color field in PPDU 1222 to a value of 0, indicating a broadcast value.

[0131] Further, in an embodiment, AP 1102 may set a UL / DL field (e.g., B6 of U-SIG-1 in U-SIG field 900) of PPDU 1222 to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1). In an embodiment, setting the BSS color field to a broadcast value (e.g., 0) and setting the UL / DL field to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1) may allow AP 1104 to receive, and decode, the PPDU 1222, because receiving AP 1104 may think PPDU 1222 is a broadcast PPDU (e.g., sent by another AP). In an embodiment, this may also be true if PPDU 1222 is an HE PPDU or an EHT PPDU: in all three examples (e.g., an HE PPDU, an EHT PPDU, or a UHR PPDU), AP 1102 may set the BSS color of PPDU 1222 to a broadcast value and the UL / DL field to indicate UL to an AP, allowing AP 1104 to receive, and decode, PPDU 1222. In the case of an HE PPDU (e.g. HE SU PPDU 410, HE MU PPDU 420, HE ERDocket No.: 25-3001 PCTSU PPDU) which doesn't include a U-SIG field, the UL / DL field and BSS color field may be indicated in the HE-SIG-A field.

[0132] For example, AP 1102 transmits PPDU 1222 with BSS color set to 0 and UL / DL set to 1. As discussed above, AP 1104 receives and decodes PPDU 1222. In an embodiment, AP 1104 transmits a BA 1224 in response.

[0133] In an embodiment, neither STA 1112 nor STA 1114 receives and decodes PPDU 1222. For example, STA 1112 may not decode PPDU 1222 (e.g. , STA 1112 may perform early receive termination) due to the UL / DL field being set to 1 (e.g., indicating transmission to an AP). STA 1114 may not decode PPDU 1222 (e.g., STA 1114 also may perform early receive termination) due to the UL / DL field being set to 1.

[0134] In an embodiment, AP 1106 receives and decodes PPDU 1222, because AP 1106 interprets PPDU 1222 as a broadcast PPDU.

[0135] To differentiate PPDU 1222 from a broadcast PPDU, AP 1102 may include in PPDU 1222 its own BSS color (e.g., BSS color=1 ). For example, if PPDU 1222 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a second BSS color field (e.g., B20-B25 of U-SIG- 1 in U-SIG field 900 illustrated in FIG. 9) to BSS color 1. If PPDU 1222 does not indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a STA-ID field (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to BSS color 1 .

[0136] Alternatively, or in addition, AP 1102 may differentiate PPDU 1222 from broadcast PPDUs transmitted by an AP by including in PPDU 1222 an AP_ID for AP 1102. For example, prior to transmission of PPDU 1222, AP 1102 and AP 1104 may negotiate an AP_ ID for AP 1102 (e.g., by exchanging one or more frames). If PPDU 1222 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the second BSS color field (e.g., B20-B25 of U-SIG- 1 in U-SIG field 900 illustrated in FIG. 9) to the negotiated AP_ID (or a portion of the bits of the negotiated AP_ID) for AP 1102. If PPDU 1222 does not indicate a URH MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the STA-ID field (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to the negotiated AP_ID for AP 1102.

[0137] In an embodiment, if the STA-ID field of PPDU 1222 is not used to identify the transmitting AP BSS color, or to identify the negotiated AP_ID, the STA-ID may be set to a disregard value (e.g., 2045).

[0138] Alternatively, or in addition, AP 1102 may indicate in PPDU 1222 a PPDU format (e.g., an inter-AP PPDU format) and / or whether PPDU 1222 is actually a broadcast PPDU. For example, AP 1102 may set a flag (e.g., a field made up of one or more bits) indicating that PPDU 1222 is an inter-AP PPDU, transmitted by one AP (e.g., AP 1102) to another AP (e.g., AP 1104) and / or indicating that PPDU 1222 is not a broadcast PPDU. In an embodiment, this indication may allow AP 1106 to identify PPDU 1222 as an inter-AP PPDU, and / or as not a broadcast PPDU, quickly and robustly, even where a data field is corrupted or where there is a collision of APJD and / or BSS color. For example, based on the indication (e.g., based on a flag in PPDU 1222), AP 1106 may filter PPDU 1222 regardless of the BSS color being set to a broadcast value (e.g., 0).Docket No.: 25-3001 PCTFurther, based on the indication, AP 1104 may set an intra-BSS NAV or an inter-BSS, even where a MAC header in PPDU 1222 is not available. In an embodiment, filtering PPDU 1222 may include not decoding further parts of PPDU 1222 (e.g., not fully decoding PPDU 1222 in its entirety, including any MAC frames contained therein).

[0139] As discussed above, one or more of these improvements discussed for example 1200 may allow for the use of more advanced PPDUs (e.g., UHR / EHT / HE PPDUs) for inter-AP communication, improving communication performance.

[0140] FIG. 13 illustrates an example 1300 of a further example operation according to an embodiment. Example 1300 includes APs 1102, 1104, and 1106. Example 1300 further includes STAs 1112 and 1114. In an embodiment, APs 1102, 1104, and 1106, and STAs 1112 and 1114, described in example 1300 correspond to APs 1102, 1104, and 1106, and STAs 1112 and 1114, described in example 1100 illustrated in FIG. 11.

[0141] As illustrated, AP 1102 transmits a frame 1316 to AP 1104. In an embodiment, AP 1102 and AP 1104 negotiate to monitor PPDUs with a particular BSS color (e.g., a pre-defined or negotiated BSS color) to identify inter-AP communication. For example. AP 1102 may transmit frame 1316 to AP 1104 indicating a proposed BSS color for inter-AP communication (e.g., a BSS color not otherwise used by any BSS). AP 1104 may respond by transmitting frame 1318, accepting the proposed BSS color for inter-AP communication, rejecting the proposed BSS color for inter-AP communication, counter-proposing a different BSS color for inter-AP communication, or providing any other suitable indication. Frames 1316 and 1318 are merely examples, and the BSS color for inter-AP communication may be negotiated using any suitable technique (e.g , AP 1104 may initiate negotiation or a suitable controller may initiate negotiation). Further, the BSS color for inter-AP communication may be pre-defined without negotiation.

[0142] As illustrated AP 1102 transmits a PPDU 1322 to AP 1104. For example, PPDU 1322 may be a UHR PPDU (e.g., UHR MU PPDU 610 illustrated in FIG. 6). In an embodiment, AP 1102 may set the BSS color of PPDU 1322 to the negotiated, or pre-defined, BSS color for inter-AP communication, as described above. For example, as illustrated in FIG. 9, a UHR PPDU may include a U-SIG (e.g., example U-SIG field 900) with a BSS color field in the version independent subfields (e.g., B7-B12 of U-SIG- 1 in U-SIG field 900). AP 1102 may set this BSS color field in PPDU 1322 to the negotiated / defined value.

[0143] Further, in an embodiment, AP 1102 may set a UL / DL field (e.g., B6 of U-SIG- 1 in U-SIG field 900) of PPDU 1322 to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1). In an embodiment, setting the BSS color field to the negotiated / defined value and / or setting the UL / DL field to indicate UL transmission of a PPDU addressed to an AP (e.g., to a value of 1) may allow AP 1104 to receive, and decode, the PPDU 1322, because receiving AP 1104 understands PPDU 1322 as an inter-AP PPDU based on the negotiated / defined BSS color value.Docket No.: 25-3001 PCT

[0144] For example, AP 1102 transmits PPDU 1322 with BSS color set to a negotiated / defined value and UL / DL set to 1. As discussed above, AP 1104 receives and decodes PPDU 1322. In an embodiment, AP 1104 transmits a BA 1324 in response.

[0145] In an embodiment, none of STA 1112, STA 1114, or AP 1106 receives and decodes PPDU 1322. For example, STA 1112 may not decode PPDU 1322 (e.g., STA 1112 may perform early receive termination) due to the BSS color being set to the negotiated / defined value (e.g., not matching the BSS color of STA 1112) and / or due to the UL / DL field being set to 1 (e.g., indicating transmission to an AP). STA 1114 may not decode PPDU 1322 (e.g., STA 1114 also may perform early receive termination) due to the BSS color being set to the negotiated / defined value (e.g., not matching the BSS color of STA 1114) and / or due to the UL / DL field being set to 1. AP 1106 may not decode PPDU 1322 (e.g., AP 1106 may perform early receive termination) due to the BSS color being set to the negotiated / defined value, rather than AP 1106’s BSS color of 3

[0146] In an embodiment, setting the BSS color of PPDU 1322 to a negotiated / defined value and the UL / DL field to 1 may not allow AP 1104 to differentiate PPDU 1322 from other, non-inter-AP, PPDUs. (e.g., where more than two APs are using a same negotiated / defined value for BSS color). The ability to differentiate between PPDUs may be critical in case PPDU 1322 is received in error, in which case AP 1104 may trigger the appropriate device for retransmission. To allow differentiation, AP 1102 may include in PPDU 1322 its own BSS color (e.g., BSS color=1). For example, if PPDU 1322 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a second BSS color field (e.g., B20-B25 of U-SIG-1 in U-SIG field 900 illustrated in FIG. 9) to BSS color 1. If PPDU 1322 does not indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a STA-ID field (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to BSS color 1.

[0147] Alternatively, or in addition, AP 1102 may differentiate PPDU 1322 from other, non-inter-AP, PPDUs by including in PPDU 1322 an APJD for AP 1102. For example, prior to transmission of PPDU 1322, AP 1102 and AP 1104 may negotiate an AP_ID for AP 1102 (e.g., by exchanging one or more frames). If PPDU 1322 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the second BSS color field (e.g., B20-B25 of U-SIG-1 in U-SIG field 900 illustrated in FIG. 9) to the negotiated AP_I D (or a portion of the bits of the negotiated AP_ID) for AP 1102. If PPDU 1322 does not indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the STA-ID field (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to the negotiated APJD for AP 1102.

[0148] In an embodiment, if the STA-ID field of PPDU 1322 is not used to identify the transmitting AP BSS color, or to identify the negotiated AP_ID, the STA-ID may be set to a disregard value (e.g., 2045).

[0149] Alternatively, or in addition, AP 1102 may indicate in PPDU 1322 a PPDU format (e.g., an inter-AP PPDU format). For example, AP 1102 may set a flag (e.g., a field made up of one or more bits) indicating that PPDU 1322 is an inter-AP PPDU, transmitted by one AP (e.g., AP 1102) to another AP (e.g., AP 1104).Docket No.: 25-3001 PCTIn an embodiment, this indication may allow AP 1104 to identify PPDU 1322 as a PPDU from another AP, quickly and robustly, even where a data field is corrupted or where there is a collision of APJD and / or BSS color. For example, based on the indication (e.g., based on a flag in PPDU 1322), AP 1104 may set an intra-BSS NAV or an inter-BSS, even where a MAC header in PPDU 1322 is not available.

[0150] As discussed above, one or more of these improvements discussed for example 1300 may allow for the use of more advanced PPDUs (e.g., UHR PPDUs) for inter-AP communication, improving communication performance.

[0151] FIG. 14 illustrates an example 1400 of a further example operation according to an embodiment. Example 1400 includes APs 1102, 1104, and 1106. Example 1400 further includes STAs 1112 and 1114. In an embodiment, APs 1102, 1104, and 1106, and STAs 1112 and 1114, described in example 1400 correspond to APs 1102, 1104, and 1106, and STAs 1112 and 1114, described in example 1100 illustrated in FIG. 11.

[0152] As illustrated AP 1102 transmits a PPDU 1422 to AP 1104. For example, PPDU 1422 may be a UHR PPDU (e.g., UHR MU PPDU 610 illustrated in FIG. 6). In an embodiment, AP 1102 may set the BSS color of PPDU 1422 to its own BSS color: BSS color=1. For example, as illustrated in FIG. 9, a UHR PPDU may include a U-SIG (e.g., example U-SIG field 900) with a BSS color field in the version independent subfields (e.g., B7-B12 of U-SIG- 1 in U-SIG field 900). AP 1102 may set this BSS color field in PPDU 1422 to a value of 1 , matching its own BSS color.

[0153] Further, in an embodiment, AP 1102 may set a UL / DL field (e.g., B6 of U-SIG- 1 in U-SIG field 900) of PPDU 1422 to indicate DL transmission from an AP of a PPDU addressed to a non-AP STA (e.g., to a value of 0). In an embodiment, AP 1102 and AP 1104 monitor each other's PPDU transmissions. For example, prior to transmission of PPDU 1422, AP 1102 and AP 1104 may negotiate to monitor PPDUs transmitted by each other (e.g., by exchanging one or more frames). As another example, AP 1102 and AP 1104 monitoring each other’s PPDUs may be a pre-defined behavior. Setting the BSS color field to the transmitting AP BSS color (e.g., 1) and setting the UL / DL field to indicate DL transmission from an AP of a PPDU addressed to a non-AP STA (e.g., to a value of 0) may allow AP 1104 to receive, and decode, the PPDU 1422, because receiving AP 1104 may monitor all PPDUs transmitted by AP 1102. In an embodiment, this may also be true if PPDU 1422 is an HE PPDU or an EHT PPDU: in all three examples (e.g., an HE PPDU, an EHT PPDU, or a UHR PPDU), AP 1102 may set the BSS color of PPDU 1422 to the transmitting AP BSS color and the UL / DL field to indicate DL from an AP, allowing AP 1104 to receive, and decode, PPDU 1422. In the case of an HE PPDU (e.g. HE SU PPDU 410, HE MU PPDU 420, HE ER SU PPDU) which doesn’t include a U-SIG field, the UL / DL field and BSS color field may be indicated in the HE-SIG-A field. Further, AP 1104 may filter, and not receive and decode, PPDUs transmitted by STAs associated with AP 1104 (e.g., STA 1112), because transmissions by STAs will have the UL / DL field set to indicate UL to an APDocket No.: 25-3001 PCT(e.g., set to 1). In an embodiment, filtering these PPDUs may include not decoding further parts of these PPDUs (e.g., not fully decoding these PPDUs in their entirety, including any MAC frames contained therein).

[0154] For example, AP 1102 transmits PPDU 1422 with BSS color set to 1 and UL / DL set to 0. As discussed above, AP 1104 is configured to monitor PPDUs transmitted by AP 1102, and so AP 1104 receives and decodes PPDU 1422. In an embodiment, AP 1104 transmits a BA 1424 in response. As discussed, AP 1104 filters any PPDUs transmitted by STA 1112, because these PPDUs will have the UL / DL field set to 1, to indicate UL to an AP.

[0155] In an embodiment, STA 1112, STA 1114, and AP 1106 do not receive and decode PPDU 1422. For example, STA 1112 may not decode PPDU 1422 (e.g., STA 1112 may perform early receive termination) due to the STA-ID in PPDU 1422 not matching the STA-ID of STA 1112. As another example, STA 1114 may not decode PPDU 1422 (e.g., STA 1114 may perform early receive termination) due to the BSS color being set to 1 , rather than STA 1114's BSS color of 2. Further, assuming AP 1106 has not also negotiated to receive PPDUs transmitted by AP 1102, AP 1106 may not decode PPDU 1422 (e.g., AP 1106 may perform early receive termination) due to the BSS color being set to 1 , rather than AP 1106’s BSS color of 3.

[0156] In an embodiment, setting the BSS color of PPDU 1422 to 1 and the UL / DL field to 0 may not allow AP 1104, and STAs associated with AP 1102 (e.g., STA 1112), to differentiate PPDU 1422 from DL PPDUs transmitted by AP 1102. The ability to differentiate between PPDUs may be critical in case PPDU 1422 is received in error, in which case AP 1104 may trigger the appropriate device for retransmission. To allow differentiation, AP 1102 may include in PPDU 1422 AP 1104’s BSS color (e.g., BSS color=2). For example, if PPDU 1422 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a second BSS color field (e.g., B20-B25 of U-SIG-1 in U-SIG field 900 illustrated in FIG. 9) to BSS color 2. If PPDU 1422 does not indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set a STA-ID field (e.g., the STAID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to BSS color 2.

[0157] Alternatively, or in addition, AP 1102 may differentiate PPDU 1422 from DL PPDUs transmitted by AP 1102 by including in PPDU 1422 an AP_ID for AP 1104. For example, prior to transmission of PPDU 1422, AP 1102 and AP 1104 may negotiate an AP_ID for AP 1104 (e.g., by exchanging one or more frames). If PPDU 1422 indicates a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the second BSS color field (e.g., B20-B25 of U-SIG-1 in U-SIG field 900 illustrated in FIG. 9) to the negotiated APJD (or a portion of the bits of the negotiated APJD) for AP 1104. If PPDU 1422 does not indicate a UHR MU PPDU variant for Co-BF or Co-SR, AP 1102 may set the STA-ID field (e.g., the STA-ID field of example UHR-SIG content channel 800 illustrated in FIG. 8) to the negotiated AP_I D for AP 1104.

[0158] As discussed above, in an embodiment AP 1102 may set the BSS color of PPDU 1422 to its own BSS color (e.g., 1) and may set the UL / DL field to indicate DL transmission from an AP of a PPDU addressed to a non-AP STA (e.g., may set the UL / DL field to 0). Alternatively, AP 1102 may set the BSS color of PPDU 1422 to its own BSS color (e.g., 1), but may set the UL / DL field to indicate UL transmission of a PPDUDocket No.: 25-3001 PCTaddressed to an AP (e.g., may set the UL / DL field to 1). Further, AP 1102 may indicate in PPDU 1422 the AP I D (e.g., a negotiated AP I D as discussed above) of AP 1104 (e.g., the receiving AP). In an embodiment, AP 1102 may include the AP_ID of AP 1104 in the STA-ID field of PPDU 1422, or in the second BSS color field of PPDU 1422 (e.g., where PPDU 1422 is used for Co-BF or Co-SR).

[0159] In an embodiment, AP 1104 may receive, and decode, PPDU 1422 transmitted by AP 1102. But AP 1104 may also decode, at least in part, PPDUs transmitted by non-AP STAs, because AP 1104 may have to use the APJD to distinguish PPDU 1422 from an UL PPDU transmitted by a non-AP STA (e.g., STA 1112 or STA 1114). Because AP 1104 must listen for PPDUs with a different BSS coIorand a UL / DL field set to 1, in the U-SIG, AP 1104 may not be able to use these fields in the U-SIG to filter UL PPDUs transmitted by STAs to their associated AP. AP 1104 may instead have to decode the PPDU up to the UHR-SIG, or even up to the data field, to identify the AP ID and filter the PPDU. For example, AP 1104 may receive an UL PPDU transmitted by STA 1112 to AP 1102, or an UL PPDU transmitted by a STA associated with AP 1106 to AP 1106. In either circumstance, AP 1104 may not be able to use the U-SIG to determine that the PPDU is an UL PPDU from a non-AP STA, rather than an inter-AP PPDU. AP 1104 may instead have to decode the PPDU up to the UHR-SIG, or up to the data field, to identify the APJD and filter the PPDU.

[0160] In an embodiment, if the STA-ID field of PPDU 1422 is not used to identify the transmitting AP BSS color, or to identify the negotiated AP_ID, the STA-ID may be set to a disregard value (e.g., 2045).

[0161] Alternatively, or in addition, AP 1102 may indicate in PPDU 1422 a PPDU format (e.g., an inter-AP PPDU format). For example, AP 1102 may set a flag (e.g., a field made up of one or more bits) indicating that PPDU 1422 is an inter-AP PPDU, transmitted by one AP (e.g., AP 1102) to another AP (e.g., AP 1104). In an embodiment, this indication may allow AP 1104 to identify PPDU 1422 as a PPDU from another AP, quickly and robustly, even where a data field is corrupted or where there is a collision of AP_ID and / or BSS color. For example, based on the indication (e.g., based on a flag in PPDU 1422), AP 1104 may set an intra-BSS NAV or an inter-BSS, even where a MAC header in PPDU 1422 is not available.

[0162] As discussed above, one or more of these improvements discussed for example 1100 may allow for the use of more advanced PPDUs (e.g., UHR / EHT / HE PPDUs) for inter-AP communication, improving communication performance.

[0163] FIG. 15 illustrates an example Universal Signal field (U-SIG) 1500 which may be used in UHR MU PPDUs, according to an embodiment. As shown in FIG. 15, U-SIG field 1500 includes two symbols, U-SIG-1 and U-SIG-2, each containing 26 bits. In an example, like U-SIG field 900 illustrated in FIG. 9, U-SIG field 1500 includes version independent subfields followed by version dependent subfields. The version independent subfields are located from bit B0 to B19 of U-SIG- 1 , while the version dependent subfields are located from bits B20 to B25 of U-SIG-1 and over all the bits of U-SIG-2.

[0164] In an embodiment, the fields of U-SIG-1 in U-SIG field 1500 correspond to the fields of U-SIG-1 discussed above for U-SIG field 900 illustrated in FIG. 9.Docket No.: 25-3001 PCT

[0165] As shown in FIG. 15, the U-SIG-2 may include a PPDU Type and Compression Mode field, similar to U-SIG field 900 illustrated in FIG. 9. In an embodiment, the PPDU Type and Compression Mode field may be used to indicate an inter-AP PPDU format (e.g., as discussed above for examples 1100, 1200, 1300, and 1400). For example, the PPDU Type and Compression Mode field may be set to a defined value (e.g., in combination with other field values and / or characteristics of the PPDU) to indicate an inter-AP PPDU format. As one example, the table below may be used:>Docket No.: 25-3001 PCT

[0166] In the example illustrated by this table, setting the PPDU Type and Compression Mode field to a value of 2, in a UHR MU PPDU with UL / DL set to 1 , a UHR-SIG present, RU allocation subfields not present, extended long range (ELR) mark and ELR-SIG not present, and one user field, indicates that the PPDU format is an inter-AP PPDU format. This is merely one example, and any suitable value(s) or combination of values may be used.

[0167] Alternatively, or in addition , in an embodiment an additional field in the PPDU may be used to indicate an inter-AP PPDU format. For example, as illustrated in FIG. 15, B8 of the U-SIG-2 may be used to indicate an inter-AP PPDU format (e.g., as discussed above for examples 1100, 1200, 1300, and 1400). For example, B8 of the U-SIG-2 may be used as a flag to indicate whether the PPDU is an inter-AP PPDU.

[0168] In addition, like U-SIG field 900, U-SIG-2 in U-SIG field 1500 may include a Co-BF / Co-SR indication field, a punctured channel information field, a UHR-SIG MCS field, a CRC field, and a tail field. These fields may correspond to the equivalent fields in U-SIG field 900.

[0169] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to implementations including more than one STA.

[0170] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to implementations including more than one AP.

[0171] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to scenarios in which any of the APs or any of the STAs may comprise a MLD, comprising at least one affiliated AP or affiliated STA.

[0172] FIG. 16 illustrates an example process 1600 according to an embodiment. Example process 1600 may be performed by a suitable AP, such as AP 1104 illustrated in FIGS. 11-14, for example. As shown in FIG. 16, process 1600 may include steps 1602 and 1604.

[0173] Step 1602 includes receiving, by a first access point (AP) from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU). The second AP may be any suitable AP, such as AP 1102 illustrated in FIGS. 11-14, for example.

[0174] In an embodiment, the first PPDU indicates a first identifier indicating a first basic service set (BSS) color.

[0175] In an embodiment, the first PPDU indicates a second identifier different from the first identifier.

[0176] In an embodiment, the first PPDU indicates a PPDU format for the first PPDU.

[0177] Step 1604 includes determining whether to filter out the first PPDU based on the PPDU format and the second identifier.

[0178] In an embodiment, the first identifier is provided in a first BSS color field of a universal signal (U-SIG) field of the PPDU.Docket No.: 25-3001 PCT

[0179] In an embodiment, the first PPDU comprises an uplink (UL)Zdownlink (DL) field.

[0180] In an embodiment, the UL / DL field indicates that the first PPDU is addressed to an AP.

[0181] In an embodiment, the first BSS color matches a BSS color of the first AP.

[0182] In an embodiment, the first BSS color matches a broadcast BSS color.

[0183] In an embodiment, the broadcast BSS color is 0.

[0184] In an embodiment, the second identifier comprises a second BSS color.

[0185] In an embodiment, the second BSS color matches a BSS color of the second AP.

[0186] In an embodiment, the second identifier comprises a first AP identifier (ID) identifying the second AP.

[0187] In an embodiment, the first PPDU comprises a station (STA) identifier field.

[0188] In an embodiment, the second identifier is provided in the STA identifier field.

[0189] In an embodiment, the STA identifier field indicates a value of at least one of: (i) 2045 or (ii) 0.

[0190] In an embodiment, the first BSS color matches a third BSS color.

[0191] In an embodiment, process 1600 further includes transmitting by the first AP to the second AP, a first frame indicating the third BSS color.

[0192] In an embodiment, process 1600 further includes receiving by the first AP from the second AP, a second frame indicating the third BSS color.

[0193] In an embodiment, the first BSS color matches a BSS color of the second AP.

[0194] In an embodiment, the UL / DL field indicates at least one of: (i) that a transmitter of the first PPDU comprises an AP or (ii) that the first PPDU is not addressed to an AP.

[0195] In an embodiment, the second identifier comprises a second BSS color matching a BSS color of the first AP.

[0196] In an embodiment, the second identifier comprises a second AP ID identifying the first AP.

[0197] In an embodiment, process 1600 further includes transmitting by the first AP to the second AP, a third frame indicating the second identifier.

[0198] In an embodiment, process 1600 further includes receiving by the first AP from the second AP, a fourth frame indicating the second identifier.

[0199] In an embodiment, the PPDU format indicates ultra-high reliability (UHR) multi-user (MU) PPDU.

[0200] In an embodiment, the PPDU format further indicates coordinated beamforming or coordinated spatial reuse.

[0201] In an embodiment, the first PPDU comprises a second BSS color field based on the PPDU format indicating coordinated beamforming or coordinated spatial reuse.

[0202] In an embodiment, the second identifier is provided in the second BSS color field.

[0203] In an embodiment, the PPDU format comprises a field indicating that the first PPDU comprises a PPDU for inter-AP communication.

[0204] In an embodiment, the field comprises a "PPDU Type and Compression Mode” field.Docket No.: 25-3001 PCT

[0205] FIG. 17 illustrates an example process 1700 according to an embodiment. Example process 1700 may be performed by a suitable AP, such as AP 1102 illustrated in FIGS. 11-14, for example. As shown in FIG 17, process 1700 may include steps 1702 and 1704.

[0206] Step 1702 includes transmitting, by a first access point (AP) to a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU). The second AP may be any suitable AP, such as AP 1104 illustrated in FIGS. 11-14, for example.

[0207] In an embodiment, the first PPDU indicates a first identifier indicating a basic service set (BSS) color.

[0208] In an embodiment, the first PPDU indicates a second identifier different from the first identifier.

[0209] In an embodiment, the first PPDU indicates a PPDU format for the first PPDU.

[0210] Step 1704 includes the second AP being configured to determine whether to filter out the first PPDU based on the PPDU format and the second identifier.

[0211] In an embodiment, first identifier is provided in a first BSS color field of a universal signal (U-SIG) field of the PPDU.

[0212] In an embodiment, the first PPDU comprises an uplink (UL)Zdownlink (DL) field.

[0213] In an embodiment, the UL / DL field indicates that the first PPDU is addressed to an AP.

[0214] In an embodiment, the first BSS color matches a BSS color of the second AP.

[0215] In an embodiment, the first BSS color matches a broadcast BSS color.

[0216] In an embodiment, the broadcast BSS color is 0.

[0217] In an embodiment, the second identifier comprises a second BSS color.

[0218] In an embodiment, the second BSS color matches a BSS color of the first AP.

[0219] In an embodiment, the second identifier comprises a first AP identifier (ID) identifying the first AP.

[0220] In an embodiment, the first PPDU comprises a station (STA) identifier field.

[0221] In an embodiment, the second identifier is provided in the STA identifier field.

[0222] In an embodiment, the STA identifier field indicates a value of at least one of: (I) 2045 or (ii) 0.

[0223] In an embodiment, the first BSS color matches a third BSS color.

[0224] In an embodiment, process 1700 further includes receiving by the first AP from the second AP, a first frame indicating the third BSS color.

[0225] In an embodiment, process 1700 further includes transmitting by the first AP to the second AP, a second frame indicating the third BSS color.

[0226] In an embodiment, the first BSS color matches a BSS color of the first AP.

[0227] In an embodiment, the UL / DL field indicates at least one of: (i) that a transmitter of the first PPDU comprises an AP or (ii) that the first PPDU is not addressed to an AP.

[0228] In an embodiment, the second identifier comprises a second BSS color matching a BSS color of the second AP.

[0229] In an embodiment, the second identifier comprises a second AP ID identifying the second AP.Docket No.: 25-3001 PCT

[0230] In an embodiment, process 1700 further includes receiving by the first AP from the second AP, a third frame indicating the second identifier.

[0231] In an embodiment, process 1700 further includes transmitting by the first AP to the second AP, a fourth frame indicating the second identifier.

[0232] In an embodiment, the PPDU format indicates ultra-high reliability (UHR) multi-user (MU) PPDU.

[0233] In an embodiment, the PPDU format further indicates coordinated beamforming or coordinated spatial reuse.

[0234] In an embodiment, wherein the first PPDU comprises a second BSS color field based on the PPDU format indicating coordinated beamforming or coordinated spatial reuse.

[0235] In an embodiment, the second identifier is provided in the second BSS color field.

[0236] In an embodiment, the PPDU format comprises a field indicating that the first PPDU comprises a PPDU for inter-AP communication.

[0237] In an embodiment, the field comprises a “PPDU Type and Compression Mode” field.

[0238] In an embodiment, an AP or STA in accordance with the above-described embodiments (e.g., any AP or STA as described in FIGS. 11-17) may perform operations as described below. A person of skill in the art based on the teachings herein would appreciate that the below described features and operations may be readily combined with the above-described embodiments.

[0239] In an aspect, one or more rules related to a PHY interface of a UHR STA may include setting TXVECTOR parameters for a UHR PPDU. A UHR STA may set the TXVECTOR parameter STAJD following rules applicable to STA I D, with the following additions. The rules that apply to an EHT MU PPDU may also apply to a UHR MU PPDU and to a UHR ELR PPDU.

[0240] A UHR STA may set the TXVECTOR parameter POWER_BOOST_FACTOR following rules applicable to POWER_BOOST_FACTOR, with the following additions. The rules that apply to an OFDMA EHT MU PPDU may also apply to an OFDMA UHR MU PPDU. The rules that apply to a non-OFDMA EHT MU PPDU may also apply to a non-OFDMA UHR MU PPDU. The POWER_BOOST_FACTOR may not be present in the TXVECTOR in a UHR TB PPDU or a UHR ELR PPDU.

[0241] A UHR STA may set the TXVECTOR parameter UPLINK_FLAG following rules applicable to UPLINK_FLAG, with the following additions. The rules that apply to an EHT MU PPDU may also apply to a UHR MU PPDU. The rules that apply to an HE ER PPDU may also apply to a UHR ELR PPDU.

[0242] A UHR STA may set the TXVECTOR parameter BSS_COLOR following rules applicable to BSS_COLOR, with the following additions. The rules that apply to an EHT MU PPDU may also apply to a UHR MU PPDU. A UHR STA that transmits a UHR ELR PPDU may set the TXVECTOR parameter BSS_COLOR to the BSS Color subfield of a most recently received or transmitted HE Operation element exchanged within the BSS of which the UHR STA is a member. A value of 0 for the TXVECTOR parameter BSS_COLOR may be disallowed for ELR PPDUs.Docket No.: 25-3001 PCT

[0243] A UHR STA may set the TXVECTOR parameter TXOP_DURATION following rules applicable to TXOP DURATION, with the following additions. The rules that apply to an EHT MU PPDU may also apply to a UHR MU PPDU. The rules that apply to an HE ER PPDU may also apply to a UHR ELR PPDU.

Claims

Docket No.: 25-3001 PCTCLAIMSWhat is claimed is:

1. A method comprising:receiving, by a first access point (AP) from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a first basic service set (BSS) color that does not match a BSS color of the first AP; a second BSS color different from the first BSS color; anda PPDU format, for the first PPDU, indicating an inter-BSS PPDU;based on the PPDU format indicating the inter-BSS PPDU, determining whether the second BSS color matches the BSS color of the first AP; andbased on the second BSS color matching the BSS color of the first AP, decoding a physical layer service data unit (PSDU) comprised in the first PPDU.

2. A method comprising:receiving, by a first access point (AP) from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a first identifier indicating a first basic service set (BSS) color;a second identifier different from the first identifier; anda PPDU format for the first PPDU; anddetermining whether to filter out the first PPDU based on the PPDU format and the second identifier.

3. The method of claim 2, wherein the first identifier is provided in a first BSS color field of a universal signal (U-SIG) field of the PPDU.

4. The method of any of claims 2-3, wherein the first PPDU comprises an uplink (UL)Zdownlink (DL) field.

5. The method of claim 4, wherein the UL / DL field indicates that the first PPDU is addressed to an AP.

6. The method of any of claims 2-5, wherein the first BSS color matches a BSS color of the first AP.

7. The method of any of claims 2-5, wherein the first BSS color matches a broadcast BSS color.

8. The method of claim 7, wherein the broadcast BSS color is 0.

9. The method of any of claims 2-8, wherein the second identifier comprises a second BSS color.

10. The method of claim 9, wherein the second BSS color matches a BSS color of the second AP.

11. The method of any of claims 2-8, wherein the second identifier comprises a first AP identifier (ID) identifying the second AP.

12. The method of any of claims 2-11, wherein the first PPDU comprises a station (STA) identifier field.

13. The method of any of claims 12, wherein the second identifier is provided in the STA identifier field.

14. The method of claim 12, wherein the STA identifier field indicates a value of at least one of: (i) 2045 or (II) 0.Docket No.: 25-3001 PCT15. The method of any of claims 2-5, wherein the first BSS color matches a third BSS color.

16. The method of claim 15, further comprising, transmitting by the first AP to the second AP, a first frame indicating the third BSS color.

17. The method of any of claims 15-16, further comprising, receiving by the first AP from the second AP, a second frame indicating the third BSS color.

18. The method of any of claims 4-5, wherein the first BSS color matches a BSS color of the second AP.

19. The method of claim 18, wherein the UL / DL field indicates at least one of: (i) that a transmitter of the first PPDU comprises an AP or (ii) that the first PPDU is not addressed to an AP.

20. The method of any of claims 18-19, wherein the second identifier comprises a second BSS color matching a BSS color of the first AP.

21. The method of any of claims 18-19, wherein the second identifier comprises a second AP ID identifying the first AP.

22. The method of any of claims 2-21, further comprising, transmitting by the first AP to the second AP, a third frame indicating the second identifier.

23. The method of any of claims 2-21 , further comprising, receiving by the first AP from the second AP, a fourth frame indicating the second identifier.

24. The method of any of claims 3-23, wherein the PPDU format indicates ultra-high reliability (UHR) multi-user (MU) PPDU.

25. The method of claim 24, wherein the PPDU format further indicates coordinated beamforming or coordinated spatial reuse.

26. The method of claim 25, wherein the first PPDU comprises a second BSS color field based on the PPDU format indicating coordinated beamforming or coordinated spatial reuse.

27. The method of claim 26, wherein the second identifier is provided in the second BSS color field.

28. The method of any of claims 2-27, wherein the PPDU format comprises a field indicating that the first PPDU comprises a PPDU for inter-AP communication.

29. The method of claim 28, wherein the field comprises a "PPDU Type and Compression Mode” field.

30. A method comprising:receiving, by a first access point (AP) from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a value in an uplink (UL)Zdownlink (DL) field; anda PPDU format for the first PPDU; anddetermining whether to filter out the first PPDU based on one or more of: (i) the PPDU format, (ii) the value indicated in the UL / DL field, and (ill) whether the second AP is a transmit opportunity (TXOP) owner.Docket No.: 25-3001 PCT31. The method of claim 30, wherein the determining whether to filter out the first PPDU is based on all of:(i) the PPDU format, (ii) the value indicated in the UL / DL field, and (Hi) whether the second AP is the TXOP owner.

32. A method comprising:receiving, by a first access point (AP) from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a station identifier (STA_ID) ; anda PPDU format for the first PPDU anddetermining whether to filter out the first PPDU based on one or more of: (i) the PPDU format, (ii) the STA_I D, and (iii) whether the first AP is a transmit opportunity (TXOP) owner.

33. The method of claim 32, wherein the determining whether to filter out the first PPDU is based on all of:(I) the PPDU format, (ii) the STAJ D, and (iii) whether the first AP is the TXOP owner.

34. The method of any of claims 32-33, wherein the determining whether to filter out the first PPDU is further based on whether the second AP has an assigned AP identifier (AP ID) by the first AP.

35. A method comprising:receiving, by a first access point (AP) from a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a PPDU format for the first PPDU;a value in an uplink (UL)Zdownlink (DL) field;a station identifier (STA ID) ; anda first identifier indicating a first basic service set (BSS) color; anddetermining whether to filter out the first PPDU based on one or more of: (i) the PPDU format, (ii) the value indicated in the UL / DL field, (iii) the STAJD, (iv) the first identifier, and (v) whether the first AP or the second AP is a transmit opportunity (TXOP) owner.

36. The method of claim 35, wherein the determining whether to filter out the first PPDU is based on all of:(I) the PPDU format, (ii) the value indicated in the UL / DL field, (iii) the STAJD, (iv) the first identifier, and (v) whether the first AP or the second AP is the TXOP owner.

37. A method comprising:transmitting, by a first access point (AP) to a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a first basic service set (BSS) color that does not match a BSS color of the second AP; a second BSS color different from the first BSS color; anda PPDU format, for the first PPDU, indicating an inter-BSS PPDU,wherein based on the PPDU format indicating an inter-BSS PPDU, the second AP is configured to determine whether the second BSS color matches the BSS color of the second AP, andDocket No.: 25-3001 PCTwherein based on the second BSS color matching the BSS color of the second AP, the second AP is configured to decode a physical layer service data unit (PSDU) comprised in the first PPDU.

38. A method comprising:transmitting, by a first access point (AP) to a second AP, a first physical layer (PHY) Protocol Data Unit (PPDU) indicating:a first identifier indicating a basic service set (BSS) color;a second identifier different from the first identifier; anda PPDU format for the first PPDU,wherein the second AP is configured to determine whether to filter out the first PPDU based on the PPDU format and the second identifier.

39. The method of claim 38, wherein the first identifier is provided in a first BSS color field of a universal signal (U-SIG) field of the PPDU.

40. The method of any of claims 38-39, wherein the first PPDU comprises an uplink (UL)Zdownlink (DL) field.

41. The method of claim 40, wherein the UL / DL field indicates that the first PPDU is addressed to an AP.

42. The method of any of claims 38-41 , wherein the first BSS color matches a BSS color of the second AP.

43. The method of any of claims 38-41 , wherein the first BSS color matches a broadcast BSS color.

44. The method of claim 43, wherein the broadcast BSS color is 0.

45. The method of any of claims 38-44, wherein the second identifier comprises a second BSS color.

46. The method of claim 45, wherein the second BSS color matches a BSS color of the first AP.

47. The method of any of claims 38-44, wherein the second identifier comprises a first AP identifier (ID) identifying the first AP.

48. The method of any of claims 38-47, wherein the first PPDU comprises a station (STA) identifier field.

49. The method of any of claims 48, wherein the second identifier is provided in the STA identifier field.

50. The method of claim 48, wherein the STA identifier field indicates a value of at least one of: (I) 2045 or (II) 0.

51. The method of any of claims 38-41 , wherein the first BSS color matches a third BSS color.

52. The method of claim 51 , further comprising, receiving by the first AP from the second AP, a first frame indicating the third BSS color.

53. The method of any of claims 51-52, further comprising, transmitting by the first AP to the second AP, a second frame indicating the third BSS color.

54. The method of any of claims 40-41 , wherein the first BSS color matches a BSS color of the first AP.

55. The method of claim 54, wherein the UL / DL field indicates at least one of: (i) that a transmitter of the first PPDU comprises an AP or (ii) that the first PPDU is not addressed to an AP.Docket No.: 25-3001 PCT56. The method of any of claims 54-55, wherein the second identifier comprises a second BSS color matching a BSS color of the second AP.

57. The method of any of claims 54-55, wherein the second identifier comprises a second AP ID identifying the second AP.

58. The method of any of claims 38-57, further comprising, receiving by the first AP from the second AP, a third frame indicating the second identifier.

59. The method of any of claims 38-57, further comprising, transmitting by the first AP to the second AP, a fourth frame indicating the second identifier.

60. The method of any of claims 39-59, wherein the PPDU format indicates ultra-high reliability (UHR) multi-user (MU) PPDU.

61. The method of claim 60, wherein the PPDU format further indicates coordinated beamforming or coordinated spatial reuse.

62. The method of claim 61 , wherein the first PPDU comprises a second BSS color field based on the PPDU format indicating coordinated beamforming or coordinated spatial reuse.

63. The method of claim 62, wherein the second identifier is provided in the second BSS color field.

64. The method of any of claims 38-63, wherein the PPDU format comprises a field indicating that the first PPDU comprises a PPDU for inter-AP communication.

65. The method of claim 64, wherein the field comprises a “PPDU Type and Compression Mode” field.

66. A device comprising:one or more processors; andmemory storing instructions that, when executed by the one or more processors, cause the device to perform a method according to any of claims 1-65.

67. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors, cause the one or more processors to perform a method according to any of claims

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