Multiple access point uplink and downlink transmissions

Abstract

The invention provides a mode for managing shared transmission under the condition of multiple APs (or BSs). A method, an apparatus, and a computer program product are provided. In one method, there is receiving, by a first access point (AP) from a second AP, a first frame indicating a modulation and coding scheme (MCS) for downlink (DL) transmission; and transmitting, by the first AP, a second frame to a second AP, the second frame indicating an allocation time of a transmission opportunity (TXOP) obtained by the first AP; and a time period for DL transmission within the allocated time, where the time period is determined based on the MCS. Further, there is a first frame received by the first access point (AP) from the second AP indicating a downlink (DL) transmission parameter for a DL transmission; and transmitting, by the first AP to the second AP, a second frame indicating a time period for DL transmission, where the time period is determined based on the DL transmission parameter.

Description

Technical Field

[0001] This invention relates to wireless communication networks, and more particularly, but not exclusively, to the implementation of IEEE 10005. TM Wireless communication networks that use the 802.11 standard. Background Technology

[0002] In densely deployed and high-demand modern wireless networks, the goal is to utilize the spectrum as efficiently as possible. Many networks use systems that “protect” upcoming transmissions, that is, to provide a device or group of devices with a transmission opportunity by requesting other devices to refrain from transmitting. This mechanism takes various forms—in the case of IEEE 802.11 (“Wi-Fi”), this is called a Transmission Opportunity (TXOP), which is obtained by a station before it transmits. To better utilize the spectrum, TXOP sharing is employed (in the case of Wi-Fi). Techniques are also used in which devices (stations or “STAs” in the case of Wi-Fi) are served by multiple access points (“APs”) or base stations (“BSs”). Summary of the Invention

[0003] This invention is defined by the appended claims. The methods, apparatus, and computer program products defined herein allow two APs (for a BS) to better manage resources when operating in a multi-AP (or BS) mode. This is achieved by sharing information between the APs (or BSs) relating to upcoming downlink (DL) and uplink (UL) transmissions.

[0004] In one aspect, a method is provided, comprising: receiving, by a first access point (AP), a first frame from a second AP indicating a modulation and coding scheme (MCS) for downlink (DL) transmission; and transmitting, by the first AP, a second frame to the second AP indicating an allocation time for a transmission opportunity (TXOP) obtained by the first AP; and a time period for DL ​​transmission within the allocation time, wherein the time period is determined based on the MCS.

[0005] In one aspect, a method is provided, comprising: receiving, by a first access point (AP), a first frame from a second AP indicating DL transmission parameters for downlink (DL) transmission; and sending, by the first AP, a second frame from the second AP indicating a time period for DL ​​transmission, wherein the time period is determined based on the DL transmission parameters.

[0006] In one aspect, a method is provided, comprising: receiving a first frame from a second AP by a first access point (AP), the first frame indicating a DL buffer status report (BSR) for downlink (DL) transmission; and sending a second frame from the first AP to the second AP, the second frame indicating the allocation time of a transmission opportunity (TXOP) obtained by the first AP, an identifier of the second AP, a time period for DL ​​transmission; and DL transmission parameters for the second AP for DL ​​transmission.

[0007] In one aspect, a method is provided comprising: transmitting a first frame from a first access point (AP) to a second AP, the first frame indicating a modulation and coding scheme (MCS) for DL ​​transmission; and receiving a second frame from the second AP by the first AP, the second frame indicating: an allocation time for a transmission opportunity (TXOP) obtained by the second AP; and a time period for DL ​​transmission within the allocation time, wherein the time period is determined based on the MCS.

[0008] In one aspect, a method is provided comprising: sending a first frame from a first access point (AP) to a second AP, the first frame indicating DL transmission parameters for downlink (DL) transmission; and receiving a second frame from the second AP by the first AP, the second frame indicating a time period for DL ​​transmission, wherein the time period is determined based on the DL transmission parameters.

[0009] In one aspect, a method is provided, comprising: sending a first frame from a second AP by a first access point (AP), the first frame indicating a DL buffer status report (BSR) for downlink (DL) transmission; and receiving a second frame from the second AP by the first AP, the second frame indicating the allocation time of a transmission opportunity (TXOP) obtained by the second AP, an identifier of the first AP, a time period for DL ​​transmission; and DL transmission parameters for the first AP to perform DL transmission.

[0010] In one aspect, there is a method comprising: receiving a first frame from a second AP by a first access point (AP), the first frame indicating uplink (UL) traffic at a station (STA) associated with the second AP; and sending a second frame from the first AP to the second AP, the second frame indicating an allocation time for a transmission opportunity (TXOP) obtained by the first AP and a time period based on UL traffic and used for UL transmissions from the STA to the second AP within the allocation time.

[0011] In one aspect, there is a method comprising: receiving, by a first access point (AP), a first frame from a second AP indicating uplink (UL) traffic of a station (STA) associated with the second AP; and sending, by the first AP, a second frame to the second AP indicating a time period for UL transmission from the STA to the second AP based on the UL traffic.

[0012] In one aspect, there is a method comprising: receiving from a second AP a first access point (AP) a first frame indicating uplink (UL) traffic for a station (STA) associated with the second AP; and transmitting from the first AP to the second AP a second frame indicating an allocation time for a transmission opportunity (TXOP) obtained by the first AP, an identifier of the second AP, a duration of uplink (UL) physical layer protocol data units (PPDUs) for UL transmissions from the STA to the second AP during the allocation time; and a modulation and coding scheme (MCS) for the UL PPDU.

[0013] In one aspect, a method includes: receiving from a second AP a first frame by a first access point (AP) a first frame indicating UL time resource information for uplink (UL) transmission from a STA to the second AP and UL frequency resource information for UL transmission; and sending from the first AP to the second AP a second frame indicating: the allocation time of a transmission opportunity (TXOP) obtained by the first AP; an identifier of the second AP; and the duration of a UL physical layer protocol data unit (PPDU) for UL transmission determined based on the UL time resource information and the UL frequency resource information.

[0014] In one aspect, there is a method comprising: sending a first frame from a first access point (AP) to a second AP indicating uplink (UL) traffic for a station (STA) associated with the first AP; and receiving a second frame from the second AP by the first AP indicating an allocation time for a transmission opportunity (TXOP) obtained by the second AP, as well as UL-based traffic during the allocation time and a time period for UL transmissions from the STA to the first AP.

[0015] In one aspect, there is a method comprising: sending a first frame from a first access point (AP) to a second AP indicating uplink (UL) traffic of a station (STA) associated with the first AP; and receiving from the second AP a second frame indicating a time period for UL transmission from the STA to the first AP based on the UL traffic.

[0016] In one aspect, there is a method that includes: A first frame indicating uplink (UL) traffic for a station (STA) associated with the first AP is sent from the first access point (AP) to the second AP; and The first AP receives a second frame from the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the second AP, the identifier of the first AP, and the duration of the UL physical layer protocol data unit (PPDU) for uplink (UL) transmission from the STA to the first AP during the allocation time; and Modulation and coding scheme (MCS) for UL PPDU.

[0017] In one aspect, there is a method comprising: sending a first frame from a first access point (AP) to a second AP, the first frame indicating UL time resource information for an uplink (UL) transmission from a STA to the first AP, and UL frequency resource information for the UL transmission; and receiving a second frame from the second AP by the first AP, the second frame indicating the allocation time of a transmission opportunity (TXOP) obtained by the second AP, an identifier of the first AP, and the duration of a UL physical layer protocol data unit (PPDU) for the UL transmission determined based on the UL time resource information and the UL frequency resource information.

[0018] In one aspect, a computer program product is provided that can be stored on a computer-readable medium and configured to perform any of the methods described herein when run on a processor.

[0019] In one aspect, an apparatus is provided that is configured to perform the methods described herein when implemented in an access point. Attached Figure Description

[0020] The above and additional objects, features, and advantages of the disclosed apparatus, system, and method will be better understood through the following illustrative and non-limiting detailed description of embodiments of the apparatus and method with reference to the accompanying drawings, wherein:

[0021] Figure 1 An exemplary wireless communication network in which embodiments of this disclosure may be implemented is shown.

[0022] Figure 2 This is a block diagram illustrating an exemplary implementation of a station (STA) and an access point (AP).

[0023] Figure 3 An example of the Media Access Control (MAC) frame format is shown.

[0024] Figure 4An example of a Quality of Service (QoS) empty frame that indicates buffer status information is shown.

[0025] Figure 5 An example format of the Physical Layer (PHY) Protocol Data Unit (PPDU) is shown.

[0026] Figure 6 An exemplary Multi-User Request Transmission (MU-RTS) trigger frame is shown that can be used during a triggered Transmission Opportunity (TXOP) Share (TXS) process.

[0027] Figure 7 An example of the TXS procedure (mode=1) is shown.

[0028] Figure 8 An example of the TXS procedure (mode=2) is shown.

[0029] Figure 9 An exemplary multi-AP network is shown.

[0030] Figure 10 This illustrates Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA).

[0031] Figure 11 This is an example illustrating the TXS process between APs.

[0032] Figure 12 An exemplary physical layer protocol data unit (PPDU) that can be used for a downlink (DL) PPDU or an uplink (UL) PPDU is shown.

[0033] Figure 13a and Figure 13b It shows in Figure 11 The image shows an example of a potential problem that may occur during the AP-to-AP TXS process.

[0034] Figure 14a and Figure 14b An example of an AP-to-AP TXS process according to one embodiment is shown.

[0035] Figure 15a and Figure 15b An example of an AP-to-TXS process according to another embodiment is shown.

[0036] Figure 16a and Figure 16b An example of an aggregate control (A-control) field that can be used in one embodiment is shown.

[0037] Figure 17a and Figure 17b An example of an information element that can be used in one embodiment is shown.

[0038] Figure 18 An example process according to one embodiment is shown.

[0039] Figure 19 Another example process according to one embodiment is shown.

[0040] Figure 20 Another example process according to one embodiment is shown.

[0041] Figure 21 Another example process according to one embodiment is shown.

[0042] Figure 22 Another example process according to one embodiment is shown.

[0043] Figure 23 Another example process according to one embodiment is shown. Detailed Implementation

[0044] In the following description, the same reference numerals denote similar or analogous elements.

[0045] In this disclosure, various embodiments are presented as examples of how the disclosed techniques and / or how the disclosed techniques can be practiced in environments and scenarios. It will be apparent to those skilled in the art that various changes in form and detail can be made without departing from the scope. After reading the specification, those skilled in the art will understand how to implement alternative embodiments. This embodiment is not limited to any of the exemplary embodiments described. Embodiments of the invention are described below in conjunction with the accompanying drawings. Limitations, features, and / or elements from the disclosed example embodiments can be combined to create further embodiments within the scope of this disclosure. Any drawings highlighting features and advantages are presented for illustrative purposes only. The disclosed architecture is flexible and configurable enough that it can be used in ways other than those shown. For example, any actions listed in the flowcharts can be reordered or used only optionally in some embodiments.

[0046] The embodiments can be configured to operate as needed. The disclosed mechanisms can be executed when certain criteria are met, for example, in a station, access point, radio environment, network, or a combination thereof. Example standards may be based at least in part on, for example, wireless device or network node configuration, traffic load, initial system setup, packet size, service characteristics, or a combination thereof. Various example embodiments can be applied when one or more criteria are met. Therefore, example embodiments that selectively implement the disclosed protocols can be implemented.

[0047] In this disclosure, “a” and “an” and similar phrases should be interpreted as “at least one” and “one or more”. Similarly, any term ending with the suffix “(s)” will be interpreted as “at least one” and “one or more”. In this disclosure, the term “may” should be interpreted as “may, for example,.” In other words, the term “may” indicates that the phrase following the term “may” is an example of one of a variety of suitable possibilities that may or may not be employed by one or more embodiments in various embodiments. As used herein, the terms “comprising” and “consisting of” enumerate one or more components of the described element. The term “comprising” is interchangeable with “including” and does not exclude the inclusion of unenumerated components in the described element. In contrast, “consisting of” provides a complete enumeration of one or more components of the described element. The term “based on” as used herein can be interpreted as “at least partially based on” rather than, for example, “based on only.” The term “and / or” as used herein refers to any possible combination of the enumerated elements. For example, “A, B and / or C” can mean A; B; C; A and B; A and C; B and C; or A, B and C. If A and B are sets and every element of A is an element of B, then 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 likewise “at least based on”) indicates that the phrase following the term “based on” is an example of one of a variety of suitable possibilities that may or may not be used in one or more embodiments in various embodiments. The phrase “in response to” (or likewise “at least in response to”) indicates that the phrase following the phrase “in response to” is an example of one of a variety of suitable possibilities that may or may not be used in one or more embodiments in various embodiments. The phrase “depends on” (or likewise “at least depends on”) indicates that the phrase following the phrase “depends on” is an example of one of a variety of suitable possibilities that may or may not be used in one or more embodiments in various embodiments. The phrase “adopts / uses” (or likewise “adopts / uses at least”) indicates that the phrase following the phrase “adopts / uses” is an example of one of a variety of suitable possibilities that may or may not be used in one or more embodiments in various embodiments.

[0048] The term "configured" can refer to the capacity of a device, regardless of whether the device is in an operational or non-operational state. "Configured" can also refer to specific settings within a device that affect its operational characteristics, regardless of whether the device is in an operational or non-operational state. In other words, hardware, software, firmware, registers, memory values, etc., can be "configured" within a device, regardless of whether the device is in an operational or non-operational state, to provide specific characteristics to the device. Terms such as "control messages generated in the device" can mean that control messages have parameters that can be used to configure specific characteristics or to implement certain actions within the device, regardless of whether the device is in an operational or non-operational state.

[0049] In this disclosure, a parameter (or equivalently referred to as a field or information element: IE) may include one or more information objects, and an information object may include one or more other objects. For example, if parameter (IE)N includes parameter (IE)M, and parameter (IE)M includes parameter (IE)K, and parameter (IE)K includes parameter (information element)J, then, for example, N includes K, and N includes J. In one example embodiment, when one or more messages / frames include multiple parameters, this means that a parameter among the multiple parameters is present in at least one of the one or more messages / frames, but not necessarily in every one of the one or more messages / frames.

[0050] Many of the features presented are described as optional using the word "may" or parentheses. For brevity and readability, this disclosure does not explicitly describe every permutation that can be obtained by selecting from the set of optional features. This disclosure will be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features can be embodied in seven ways: having only one of the three possible features, having any two of the three possible features, or having three of the three possible features.

[0051] Many of the elements described in the disclosed embodiments can be implemented as modules. A module is defined herein as an element that performs a defined function and has a defined interface to other elements. Modules described in this disclosure can be implemented in hardware, software combined with hardware, firmware, wet hardware (e.g., hardware with biological elements), or a combination thereof, and may be behaviorally equivalent. For example, a module can 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, etc.) or a modeling / simulation program (such as Simulink, Stateflow, GNU Octave, or LabVIEW MathScript). Modules can be implemented using physical hardware that combines discrete or programmable analog, digital, and / or quantum hardware. Examples of programmable hardware include: 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, and C++. FPGAs, ASICs, and CPLDs are typically programmed using hardware description languages ​​(HDLs) (e.g., VHSIC Hardware Description Language (VHDL) or Verilog), which configure the connections between internal hardware modules with a limited set of functions on the programmable device. The techniques mentioned are often used in combination to achieve the desired functional modules.

[0052] The inventors have recognized certain problems with TXOP sharing when using multiple access points (APs). For downlink (DL), there are buffer status report (BSR) frames that indicate the characteristics of buffered traffic. In multi-AP TXOP sharing, the sharing AP needs to know the transmission parameters that the sharing AP intends / needs to use for upcoming DL transmissions—the AP may know, for example, the MCS used by the STA for uplink (UL) transmissions, but it cannot know the expected MCS used for DL ​​responses. Similarly, in the UL case, the sharing AP does not know the expected transmissions from the UL to the sharing AP and may allocate resources inefficiently.

[0053] Figure 1 An example wireless communication network in which embodiments of the present disclosure can be implemented is shown.

[0054] like Figure 1 As shown, an example wireless communication network may include an IEEE 802.11 (WLAN) infrastructure network 102. WLAN infrastructure network 102 may include one or more Basic Service Sets (BSS) 110 and 120 and a Distribution System (DS) 130.

[0055] BSS 110-1 and 110-2 each comprise a set of access points (APs or AP STAs) and at least one station (STAs or non-AP STAs). For example, BSS 110-1 includes AP 104-1 and STA 106-1, and BSS 110-2 includes AP 104-2 and STAs 106-2 and 106-3. The APs and at least one STA in the BSS perform an association process to communicate with each other.

[0056] The DS 130 can be configured to connect BSS 110-1 and BSS 110-2. In this way, the DS 130 can enable Extended Service Set (ESS) 150. Within the ESS 150, APs 104-1 and 104-2 are connected via the DS 130 and can have the same Service Set Identifier (SSID).

[0057] The WLAN infrastructure network 102 can be coupled to one or more external networks. For example, such as Figure 1 As shown, WLAN infrastructure network 102 can be connected to another network 108 (e.g., 802.X) via portal 140. Portal 140 can be used as a bridge to connect DS 130 of WLAN infrastructure network 102 to other networks 108.

[0058] Figure 1 The exemplary wireless communication network shown may further include one or more ad-hoc networks or independent BSSs (IBSSs). An ad-hoc network or IBSS is a network of multiple STAs included within each other's communication range. The multiple STAs are configured such that they can communicate with each other using direct peer-to-peer communication (i.e., not via an AP).

[0059] For example, in Figure 1 In this configuration, STAs 106-4, 106-5, and 106-6 can be configured to form a first IBSS 112-1. Similarly, STAs 106-7 and 106-8 can be configured to form a second IBSS 112-2. Since an IBSS does not include an AP, it does not include a centralized management entity. Instead, STAs within the IBSS are managed in a distributed manner. STAs forming an IBSS can be fixed or mobile.

[0060] A STA, serving as a predefined functional medium, may include a Media Access Control (MAC) layer conforming to the IEEE 802.11 standard. A physical layer interface for the radio medium can be used between APs and non-AP stations (STAs). STA may also be referred to using various other terms, including mobile terminal, radio device, radio transceiver unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, or user. For example, the term "user" may be used to refer to a STA participating in uplink multi-user multiple-input multiple-output (MU MIMO) and / or uplink orthogonal frequency division multiple access (OFDMA) transmissions.

[0061] A Physical Layer (PHY) Protocol Data Unit (PPDU) can be a composite structure including a payload in the form of a PHY preamble and a PHY Service Data Unit (PSDU). For example, a PSDU may include a PHY preamble and a header and / or one or more MAC Protocol Data Units (MPDUs). The receiving device can use the information provided in the PHY preamble to decode subsequent data in the PSDU. When transmitting a PPDU via a bonded channel (a channel formed by channel bonding), the preamble field can be copied 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"). A legacy preamble can be used for packet detection, automatic gain control, and channel estimation, among other things. A legacy preamble is also typically used to maintain compatibility with legacy equipment. The format, encoding, and information provided in the non-legacy portion of the preamble are based on the specific IEEE 802.11 protocol to be used to transmit the payload.

[0062] A frequency band can include one or more sub-bands or frequency channels. For example, PPDUs conforming to IEEE 802.11n, 802.11ac, 802.11ax, and / or 802.11be standard revisions can be transmitted in 2.4 GHz, 5 GHz, and / or 6 GHz frequency bands, each of which can be divided into multiple 20 MHz channels. PPDUs can be transmitted on physical channels with a minimum bandwidth of 20 MHz. Larger channels can be formed through channel bonding. For example, PPDUs can be transmitted on physical channels with bandwidths of 40 MHz, 80 MHz, 160 MHz, or 320 MHz by bonding multiple 20 MHz channels together.

[0063] Figure 2 This is a block diagram illustrating exemplary implementations of STA 210 and AP 260. (As shown...) Figure 2As shown, STA 210 may include at least one processor 220, memory 230, and at least one transceiver 240. AP 260 may include at least one processor 270, memory 280, and at least one transceiver 290. Processors 220 / 270 may be operatively connected to memory 230 / 280 and / or transceiver 240 / 290.

[0064] Processors 220 / 270 can implement the functions of the PHY layer, MAC layer, and / or logical link control (LLC) layer of the corresponding device (STA 210 or AP 260). Processors 220 / 270 may include one or more processors and / or one or more controllers. One or more processors and / or one or more controllers may include, for example, general-purpose processors, digital signal processors (DSPs), microcontrollers, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), logic circuits, or chipsets.

[0065] Memory 230 / 280 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage units. Memory 230 / 280 may include one or more non-transitory computer-readable media. Memory 230 / 280 may store computer program instructions or code that can be executed by processor 220 / 270 to perform one or more operations / embodiments discussed in this application. Memory 230 / 280 may be implemented (or located) within or outside of processor 220 / 270. Memory 230 / 280 may be operatively connected to processor 220 / 270 via various means known in the art.

[0066] Transceiver 240 / 290 can be configured to transmit / receive radio signals. In one embodiment, transceiver 240 / 290 can implement the PHY layer of a corresponding device (STA 210 or AP 260). In an embodiment, STA 210 and / or AP 260 can be multi-link devices (MLDs), which are devices capable of operating on multiple links defined by the IEEE 802.11 standard. Thus, STA 210 and / or AP 260 can each implement multiple PHY layers. Multiple PHY layers can be implemented using one or more of transceivers 240 / 290.

[0067] Target Wake-up Time (TWT) (a feature introduced in the IEEE 802.11ah standard) allows STAs to manage activity in the BSS by scheduling STAs to operate at different times to reduce contention. TWT allows STAs to reduce the amount of time required for a STA to wake up when utilizing power management modes. TWTs can be individual TWTs or broadcast TWTs. Individual TWTs follow a TWT protocol negotiated between STAs. Broadcast TWTs are based on a scheduling set and are provided to STAs by the AP.

[0068] In an individual TWT, the STA that requests the TWT agreement is called the TWT-requesting STA. For example, the TWT-requesting STA can be a non-AP STA. The STA that responds to the request is called the TWT-responding STA. The TWT-responding STA can be, for example, an AP. The TWT-requesting STA is assigned a specific time to wake up and exchange frames with the TWT-responding STA. The TWT-requesting STA can transmit wake-up scheduling information to the TWT-responding STA. When a TWT agreement is established between the TWT-requesting STA and the TWT-responding STA, the TWT-responding STA can send a TWT value to the TWT-requesting STA.

[0069] When using explicit TWT, the TWT requesting STA can wake up and perform frame exchange. The TWT requesting STA can receive the next TWT information in the response from the TWT responding STA. When using implicit TWT, the TWT requesting STA can calculate the next TWT by adding a fixed value to the current TWT value.

[0070] The TWT value used for implicit TWTs can be periodic. A TWT request STA operating with an implicit TWT protocol can determine the start time of the next TWT service session (TWT SP) by adding the value of the TWT wake-up interval associated with the TWT protocol to the start time of the current TWT SP. A TWT response STA can include the start times of a series of TWT SPs corresponding to a single TWT stream identifier of the implicit TWT protocol in the target wake-up time field of the TWT element. The TWT element can include the value 'Accept TWT' in the TWT setup command field. The start time of a TWT SP sequence can indicate the start time of the first TWT SP in the sequence. The start time of subsequent TWT SPs can be determined by adding the value of the TWT wake-up interval to the start time of the current TWT SP. In one example, a TWT request STA waking up for an implicit TWT SP can enter a dormant state after the TWT SP has elapsed or after receiving a service session end (EOSP) field equal to 1 from the TWT response STA (whichever occurs first).

[0071] A TWT session can be negotiated between the AP and STA. The TWT session can be configured with TWT SPs for DL ​​and UL services between the AP and STA. Expected services may be limited to the negotiated SP. A TWT SP can start at a specific time. A TWT SP can run for a specific duration. A TWT SP can repeat for each SP interval.

[0072] Figure 3 Example 300 of the MAC frame format is shown. In operation, the STA can construct a subset of MAC frames for transmission and can decode a subset of received MAC frames during verification. The specific subset of frames that the STA can construct and / or decode can be determined by the functions supported by the STA. The STA can use the Frame Check Sequence (FCS) contained in the frame to verify the received MAC frame and can interpret certain fields from the MAC header of all frames.

[0073] like Figure 3 As shown, a MAC frame includes a MAC header, a variable-length frame body, and a frame check sequence (FCS).

[0074] The MAC header includes a frame control field, an optional duration / ID field, an address field, an optional sequence control field, an optional QoS control field, and an optional HT control field.

[0075] The frame control field includes the following subfields: protocol version, type, subtype, to DS, from DS, more fragments, retry, power management, more data, protected frames, and +HTC.

[0076] The protocol version subfield remains unchanged in size and layout across all revisions of the IEEE 802.11 standard. For MAC frames, the value of the protocol version subfield is 0.

[0077] The type and subtype subfields together identify the function of a MAC frame. There are three frame types: control, data, and management. Each frame type has several defined subtypes. Bits within the subtype subfield are used to indicate specific modifications to the underlying data frame (subtype 0). For example, in a data frame, the most significant bit (MSB) of the subtype subfield (bit 7 (B7) of the frame control field) is defined as the QoS subfield. When the QoS subfield is set to 1, it indicates a QoS subtype data frame, which is a data frame that includes a QoS control field in its MAC header. When set to 1 in the data subtype, the second MSB of the subtype field (bit 6 (B6) of the frame control field) indicates a data frame that does not include a frame body field.

[0078] The "To DS" subfield indicates whether the data frame is destined for the Distribution System (DS). The "From DS" subfield indicates whether the data frame originated from the DS.

[0079] In all data or management frames where the MAC Service Data Unit (MSDU) or MAC Management Protocol Data Unit (MMPDU) carried by the MAC frame has another fragment to follow, set the More Fragments subfield to 1. In all other frames where the More Fragments subfield exists, set it to 0.

[0080] The retry subfield is set to 1 in any data or management frame that is a retransmission of an earlier frame. It is set to 0 in all other frames in which the retry subfield exists. The receiving STA uses this indication to aid in its process of eliminating duplicate frames. These rules do not apply to frames transmitted by the STA under the block protocol.

[0081] The power management subfield is used to indicate the power management mode of the STA.

[0082] The More Data subfield indicates to the STA in Power Saving (PS) mode that a bufferable unit (BU) is buffered for that STA at the AP. The More Data subfield is valid in separately addressed data or management frames sent by the AP to the STA in PS mode. The More Data subfield is set to 1 to indicate the presence of at least one additional buffered BU for the STA.

[0083] If the frame body field contains information that has already been processed by the cryptographic encapsulation algorithm, then the protected frame subfield is set to 1.

[0084] The +HTC subfield indicates that the MAC frame contains the HT control field.

[0085] The Duration / ID field in the MAC header indicates various aspects depending on the frame type and subtype, as well as the QoS capabilities of the sending STA. For example, in a control frame of the Power Saving Polling (PS-Poll) subtype, the Duration / ID field carries the Association Identifier (AID) of the STA sending the frame in 14 least significant bits (LSBs), and both most significant bits (MSBs) are set to 1. In other frames sent by the STA, the Duration / ID field contains a duration value (in microseconds) that is used by the receiver to update the Network Allocation Vector (NAV). The NAV is a counter that indicates to the STA the amount of time it must postpone access to the shared medium.

[0086] A MAC frame format can have up to four address fields. These fields are used to indicate the Basic Service Set Identifier (BSSID), source address (SA), destination address (DA), sending address (TA), and receiving address (RA). Some frames may not contain some of these address fields. Some address fields are specified using the relative positions of address fields (1-4) within the MAC header, regardless of the address type present in that field. Specifically, address 1 always identifies the intended receiver of the frame, and address 2 (if present) always identifies the transmitter of the frame.

[0087] The sequence control field consists of two subfields: the sequence number subfield and the fragment number subfield. In a data frame, the sequence number subfield indicates the sequence number of the MSDU (if not in an aggregated MSDU (A-MSDU)) or A-MSDU. In a management frame, the sequence number subfield indicates the sequence number of the frame. The fragment number subfield indicates the number of each fragment of the MSDU or MMPDU. The fragment number is set to 0 in the first or only fragment of the MSDU or MMPDU and increments by 1 for each subsequent fragment of that MSDU or MMPDU. In a MAC Protocol Data Unit (MPDU) containing an A-MSDU, or in an MPDU containing an unsegmented MSDU or MMPDU, the fragment number is set to 0. The fragment number remains constant throughout all retransmissions of the fragment.

[0088] The QoS control field identifies the service category (TC) or service flow (TS) to which the MAC frame belongs. The QoS control field can also indicate various other QoS-related, A-MSDU-related, and mesh-related information about the frame. This information can vary depending on the frame type, frame subtype, and the type of STA transmitting the frame. The QoS control field exists in all data frames where the QoS subfield of the subtype subfield is equal to 1.

[0089] The HT control field exists in QoS data, QoS empty and management frames, which are determined by the +HTC subfield of the frame control field.

[0090] The frame body field is a variable-length field that contains information specific to each frame type and subtype. It can include one or more MSDUs or MMPDUs. The minimum length of the frame body is 0 octets.

[0091] The FCS field contains a 32-bit Cyclic Redundancy Check (CRC) code. The FCS field value is calculated from all fields in the MAC header and frame body.

[0092] Figure 4Example 400 of a Quality of Service (QoS) empty frame indicating buffer status information is shown. A QoS empty frame is a QoS data frame with an empty frame body. A QoS empty frame includes a QoS control field and an optional HT control field, which may contain a Buffer Status Report (BSR) control subfield. A QoS empty frame indicating buffer status information can be sent by a STA to an AP.

[0093] QoS control fields may include a Service Identifier (TID) subfield, an Acknowledgment Policy Indicator subfield, and a queue size subfield (or a Transmission Opportunity (TXOP) Duration Request subfield).

[0094] The TID subfield identifies the TC or TS requesting a TXOP by setting the requested TXOP duration or queue size subfield. The encoding of the TID subfield depends on the access policy (e.g., allowed values ​​of 0 to 7 for Enhanced Distributed Channel Access (EDCA) access policies to identify the user priority of the TC or TS).

[0095] The ack policy indicator subfield, along with other information, identifies the acknowledgment policy followed during MPDU delivery (e.g., normal ack, implicit block ack request, no ack, block ack, etc.).

[0096] The queue size subfield is an 8-bit field that indicates the amount of buffered traffic at the STA for a given TC or TS, intended for transmission to the AP identified by the receiver address of the frame containing the subfield. The queue size subfield is present in QoS empty frames transmitted by the STA when bit 4 of the QoS control field is set to 1. The AP can use the information contained in the queue size subfield to determine the duration of a TXOP allocated to the STA or to determine the uplink (UL) resources allocated to the STA.

[0097] In frames transmitted by or to inefficient (non-HE) STAs, the following rules may be applied to queue size values:

[0098] - The queue size value is an approximate total size of all MSDUs and A-MSDUs buffered at the STA in the delivery queue for MSDUs and A-MSDUs (excluding MSDUs or A-MSDUs included in the current QoS data frame), rounded up to the nearest multiple of 256 octets and represented in units of 256 octets, where the TID value is equal to the value indicated in the TID subfield of the QoS control field.

[0099] - The queue size value of 0 is only used to indicate that there are no buffered transactions in the queue used for the specified TID.

[0100] The queue size value of 254 is used for all sizes greater than 64,768 octets.

[0101] The queue size value of 255 is used to indicate an unspecified or unknown size.

[0102] In frames sent from HE STA to HE AP, the following rules can be applied to queue size values.

[0103] The queue size value QS is an approximate total size in octet of all MSDUs and A-MSDUs buffered at the STA in the delivery queue for MSDUs and A-MSDUs (including MSDUs or A-MSDUs contained in the same PSDU as the frame containing the queue size subfield), where the TID value is equal to the value indicated in the TID subfield of the QoS control field.

[0104] The queue size subfield includes the scaling factor subfield in bits B14-B15 of the QoS control field and the unscaled value UV in bits B8-B13 of the QoS control field. The scaling factor subfield provides the scaling factor.

[0105] The STA obtains the queue size QS from the received QoS control field, as shown below. This QoS control field contains a scaling factor SF and an unscaled value UV: Qs = 16×UV, if SF equals 0; 1024 + 256 × UV, if SF equals 1; 17 408 + 2048 × UV, if SF equals 2; 148 480+32 768×UV, if SF equals 3 and UV is less than 62; >2 147 328, if SF equals 3 and UV equals 62; Unspecified or unknown if SF equals 3 and UV equals 63.

[0106] The TXOP Duration Request subfield, which can be included in place of the Queue Size subfield, indicates the duration in 32 microseconds (µs) that the sending STA needs to determine for the next TXOP for the specified TID. The TXOP Duration Request subfield is set to 0 to indicate that no TXOP is requested for the specified TID during the current Service Hour (SP). The TXOP Duration Request subfield is set to a non-zero value to indicate the requested TXOP duration in increments of 32 µs, ranging from 32 µs to 8160 µs.

[0107] The HT control field may include a BSR control subfield, which may contain buffer status information for UL MU operation. The BSR control subfield may be formed by the Access Category Index (ACI) bitmap subfield, the Incremental TID subfield, the ACI High subfield, the Scaling Factor subfield, the Queue Size High subfield, and all queue size subfields of the HT control field.

[0108] The ACI bitmap field indicates the access category for reporting buffer status (e.g., B0: Best Effort (AC_BE), B1: Background (AC_BK), B2: Video (AC_VI), B3: Voice (AC_VO), etc.). Each bit of the ACI bitmap subfield is set to 1 to indicate that the buffer status of the corresponding AC is included in the full queue size subfield, otherwise it is set to 0, except that if the ACI bitmap subfield is 0 and the incremental TID subfield is 3, then the buffer status of all 8 TIDs is included.

[0109] The incremental TID subfield, together with the value of the ACI bitmap subfield, indicates the number of TIDs that the STA is reporting the buffer status for.

[0110] The ACI high subfield indicates the ACI of the AC of the BSR indicated in the queue size high subfield. The ACI to AC mapping is defined as ACI value 0 mapping to AC_BE, ACI value 1 mapping to AC_BK, ACI value 2 mapping to AC_VI, and ACI value 3 mapping to AC_VO.

[0111] The scaling factor subfield indicates the queue size in units of SF (in octets) for the high end of the queue and the queue size for all subfields.

[0112] The queue size high subfield indicates, in SF octets, the amount of buffered traffic for the AC identified by the ACI high subfield, which is intended for the STA identified by the receiver address of the frame containing the BSR control subfield.

[0113] For all Acs identified by the ACI bitmap subfield, the queue size of all subfields indicates the buffered traffic in SF octets, which is intended for the STA identified by the receiver address of the frame containing the BSR control subfield.

[0114] The queue size values ​​in both the queue size high and queue size all subfields are the total size of all MSDUs and A-MSDUs buffered at the STA in the delivery queues of the MSDUs and A-MSDUs associated with the AC, as specified in the ACI high and ACI bitmap subfields respectively, including MSDUs or A-MSDUs contained in the same PSDU as the frame containing the BSR control subfield, rounded up to the nearest multiple of the SF octet.

[0115] A queue size value of 254 in both the queue size high and all queue size subfields indicates a buffered traffic volume greater than 254 × SF octets. A queue size value of 255 in both the queue size high and all queue size subfields indicates that the buffered traffic volume is unspecified or unknown. The queue size value for QoS data frames containing fragments can remain constant, even if the amount of queued traffic changes as consecutive fragments are sent.

[0116] The MAC service provides the ability to exchange MSDUs with peer entities. To support this service, the local MAC uses an underlying PHY-level service to transfer MSDUs to the peer MAC entity. This asynchronous MSDU transfer is performed on a connectionless basis.

[0117] Figure 5 An example format of a PPDU is shown. As shown, a PPDU may include a PHY preamble, a PHY header, a PSDU, and a tail and padding bits.

[0118] A PSDU may include one or more MPDUs, such as a QoS data frame, an MMPDU, a MAC control frame, or a QoS empty frame. When an MPDU carries a QoS data frame, the frame body of the MPDU may include an MSDU or an A-MSDU.

[0119] By default, MSDU transmission is based on a best-effort approach. That is, there is no guarantee that the transmitted MSDU will be successfully delivered. However, QoS facilities use Service Identifiers (TIDs) to specify differentiated services based on each MSDU.

[0120] The STA can differentiate MSDU delivery based on the specified service category (TC) or service flow (TS) of an individual MSDU. The MAC sublayer entity determines the user priority (UP) for the MSDU based on the TID value provided with the MSDU. The QoS facility supports eight UP values. The UP values ​​range from 0 to 7 and form an ordered sequence of priorities, where 1 is the lowest value, 7 is the highest value, and 0 falls between 2 and 3.

[0121] MSDUs with a specific UP are referred to as belonging to the service category of that UP. Each MSDU at the Media Access Control Service Access Point (MAC SAP) can be provided directly to the UP in the UP parameters. Aggregated MPDUs (A-MPDUs) can include MPDUs with different TID values.

[0122] The STA can deliver Buffer Status Reports (BSRs) to assist the AP in allocating UL MU resources. The STA can deliver a BSR implicitly in the QoS control field or BSR control subfield of any frame transmitted to the AP (unrequested BSR), or explicitly in a frame sent to the AP in response to a BSRP trigger frame (requested BSR).

[0123] The buffer status reported in the QoS control field includes the queue size value for a given TID. The buffer status reported in the BSR control field includes the ACI bitmap, differential TID, high-priority AC, and two queue sizes.

[0124] The STA can report the buffer status of the QoS empty frames and QoS data frames sent to the AP in the QoS control field, and report the buffer status of the QoS empty frames, QoS data frames and management frames sent to the AP in the BSR control subfield (if present), as defined below.

[0125] The STA can report the queue size for a given TID in the queue size subfield of the QoS control field of the transmitted QoS data frame or QoS empty frame; the STA can set the queue size subfield to 255 to indicate an unknown / unspecified queue size for that TID. The STA can aggregate multiple QoS data frames or QoS empty frames in the A-MPDU to report queue sizes for different TIDs.

[0126] If the AP has indicated its support for the receive BSR control subfield, the STA can report the buffer status in the BSR control subfield of the transmitted frame.

[0127] The High Efficiency (HE) STA can report the queue size for a preferred AC, indicated by the ACI high subfield, in the queue size high subfield of the BSR control subfield. The STA can set the queue size high subfield to 255 to indicate an unknown / unspecified queue size for that AC.

[0128] The HE STA can report the queue size for an AC as indicated by the ACI bitmap field in all subfields of the queue size control subfield. The STA can set all subfields of queue size to 255 to indicate unknown / unspecified BSRs for those ACs.

[0129] Triggered TXOP Sharing (TXS) is a technology introduced in the IEEE 802.11be standard revision. TXS allows an AP to allocate the duration within a acquired TXOP to a STA for transmitting one or more non-triggered (non-TB) PPDUs. For a TXS procedure, the AP can transmit a Multi-User Request to Transmit (MU-RTS) trigger frame with a triggered TXOP sharing mode subfield set to a non-zero value. An MU-RTS trigger frame is used to trigger CTS frames from multiple users. An MU-RTS trigger frame with a triggered TXOP sharing mode subfield set to a non-zero value is called a MU-RTS TXS Trigger (MRTT) frame.

[0130] In one example, when the triggered TXOP sharing mode subfield is set to 1, the STA can send one or more non-TB PPDUs to the AP during the allocated duration. In another example, when the triggered TXOP sharing mode subfield is set to 2, the STA can send one or more non-TB PPDUs to the AP or a peer STA during the allocated duration. A peer STA can be a STA with a connection for peer-to-peer (P2P) communication or direct communication with the STA. In this example, a direct radio link is established according to the Tunnel Direct Link Establishment (TDLS) protocol.

[0131] Figure 6 An exemplary MRTT frame 600 that can be used in the TXS process is shown. Figure 6 As shown, the example MRTT frame 600 may include a frame control field, a duration field, a receiver address (RA) field, a transmitter address (TA) field, a common information field, a user information list field, a padding field, and / or a frame check sequence (FCS) field.

[0132] In one example, the public information field could be a high-efficiency (HE) variable public information field or an extremely high-throughput (EHT) variable public information field. For example... Figure 6 As shown, the EHT variable public information field may include one or more of the following subfields: trigger type, UL length, additional TF, required CS, UL BW, GI and HE / EHT-LTF type / triggered TXOP sharing mode, number of HE / EHT-LTF symbols, LDPC additional symbol fragments, AP Tx power, pre-FEC fill factor, PE disambiguation, UL space reuse, HE / EHT P160, special user information field flag, EHT reservation, reservation, or trigger-related public information.

[0133] The trigger type subfield indicates that frame 600 is an MRTT frame.

[0134] The GI and HE / EHT-LTF type / triggered TXOP sharing mode subfield can include a triggered TXOP sharing mode subfield. In one example, the triggered TXOP sharing mode subfield can be set to a non-zero value (e.g., 1 or 2). In one example, the triggered TXOP sharing mode subfield can be set to 1. This allows the triggered TXOP sharing mode subfield to indicate that the STA indicated by the AID12 subfield of the User Information field (of the User Information List field) can send one or more non-TB PPDUs to the AP during the time period indicated by the Allocation Duration subfield of the User Information field. In another example, the triggered TXOP sharing mode subfield can be set to 2. This allows the triggered TXOP sharing mode subfield to indicate that the STA indicated by the AID12 subfield of the User Information field (of the User Information List field) can send one or more non-TB PPDUs to the AP or a peer STA during the time period indicated by the Allocation Duration subfield of the User Information field. In one example, a peer STA can be a STA with a connection for P2P communication or direct communication with the STA.

[0135] The user information list fields can include one or more user information fields. In the example, such as... Figure 6 As shown, the EHT variable user information field may include one or more of the following subfields: AID12, RU allocation, allocation duration, reservation, or PS160.

[0136] The AID12 subfield can indicate the associated identifier (AID) of the STA that can use the time indicated by the Assigned Duration subfield.

[0137] The RU allocation subfield can indicate the location and size of the RU allocated to the STA, as indicated by the AID12 subfield.

[0138] The allocation duration subfield can indicate the time allocated by the AP that sent the MRTT frame 600. The allocated time can be a portion of the TXOP obtained by the AP. In an example embodiment, the allocation duration subfield can indicate a first time period.

[0139] Figure 7 Example 700 of the TXS procedure (mode = 1) is shown. Figure 7As shown, the TXS procedure can begin when AP 710 sends an MRTT frame 720 to STA 711. The MRTT frame 720 may allocate a portion of the TXOP obtained by AP 710 to STA 711 and may indicate a TXS mode equal to 1. STA 711, receiving the MRTT frame 720, can use the allocated time to send one or more non-TB PPDUs to AP 710. The one or more non-TB PPDUs may include data frames, control frames, management frames, or action frames.

[0140] In the example, MRTT frame 720 may include a triggered TXOP shared mode subfield indicating TXS mode and / or a subfield indicating a first time period corresponding to the allocated time. In the example, the first time period may be set to a value of X microseconds (µs).

[0141] STA 711 can respond to MRTT frame 720 by sending CTS frame 721 to AP 710. Subsequently, STA 711 can send non-TB PPDUs 722, 724, including one or more data frames, to AP 710 during the first time period indicated in MRTT frame 720. In one example, AP 710 can send one or more block Ack (BA) frames 723, 725 in response to one or more data frames contained in the non-TB PPDUs 722, 724 received from STA 711.

[0142] Figure 8 Example 800 of the TXS procedure (mode = 2) is shown. Figure 8 As shown, the TXS procedure can begin when AP 810 sends MRTT frame 820 to STA 811. MRTT frame 820 may allocate a portion of the TXOP obtained by AP 810 to STA 811 and may indicate a TXS mode equal to 2. STA 811, receiving MRTT frame 820, can use the allocated time to send one or more non-TB PPDUs to STA 812. The one or more non-TB PPDUs may include data frames, control frames, management frames, or action frames.

[0143] In the example, MRTT frame 820 may include a TXOP shared mode subfield indicating the triggering of TXS mode and / or a subfield indicating a first time period corresponding to the allocated time. In the example, the first time period may be set to a value of X microseconds (µs).

[0144] STA 811 can respond to MRTT frame 820 by sending CTS frame 821 to AP 810. Subsequently, STA 811 can send non-TB PPDUs 822, 824, including one or more data frames, to STA 818 during the first time period indicated in MRTT frame 720. In one example, STA 812 can send one or more BA frames 823, 825 in response to one or more data frames contained in the non-TB PPDUs 822, 824 received from STA 811.

[0145] Figure 9 An example multi-AP network 900 is shown. The example multi-AP network 900 can be a multi-AP network according to the Wi-Fi Alliance standard specifications for multi-AP networks. For example... Figure 9 As shown, the multi-AP network 900 may include a multi-AP controller 902 and multiple multi-AP groups (or multi-AP sets) 904, 906 and 908.

[0146] The multi-AP controller 902 can be a logical entity that implements the logic for controlling the APs in the multi-AP network 900. The multi-AP controller 902 can receive capability information and measurements from the APs and can trigger AP control commands and operations on the APs. The multi-AP controller 902 can also provide loading functionality to load APs and provide them to the multi-AP network 900.

[0147] Multiple AP groups 904, 906, and 908 can each include multiple APs. APs within a multiple AP group are within each other's communication range. However, APs within a multiple AP group do not need to have the same primary channel. As used herein, the primary channel for an AP refers to the default channel that the AP uses to monitor management frames and / or to transmit beacon frames. For a STA associated with an AP, the primary channel refers to the AP's primary channel, which is advertised via AP beacon frames.

[0148] In one approach, one of the APs in a multi-AP group can be designated as the master AP. The designation of the master AP can be done by the AP controller 902 or by the APs in the multi-AP group. The master AP of the multi-AP group can be fixed or can change over time among the APs in the multi-AP group. APs that are not the master APs in the multi-AP group are referred to as slave APs. In one approach, the master AP can be within communication range of all slave APs in the multi-AP group, and vice versa. A slave AP may not be within communication range of another slave AP in the multi-AP group.

[0149] In one approach, the APs in a multi-AP group can coordinate with each other, including coordinating transmissions within the multi-AP group. One aspect of this coordination may include coordinating to perform multi-AP transmissions within the multi-AP group. As used herein, a multi-AP transmission is a transmission event in which multiple APs (in a multi-AP group or network) transmit simultaneously within a time period. The time period for simultaneous AP transmissions can be consecutive. Multi-AP transmissions can use different transmission techniques, such as coordinated OFDMA, coordinated spatial reuse, joint transmission and reception, coordinated beamforming and coordinated time division multiple access (TDMA), or a combination of two or more of the foregoing techniques.

[0150] Multi-AP group coordination can be enabled by the AP controller and / or the master AP of the multi-AP group. In one approach, the AP controller and / or the master AP can control time and / or frequency sharing in a TXOP. For example, when one of the APs in the multi-AP group (e.g., the master AP) acquires a TXOP, the AP controller and / or the master AP can control how the time / frequency resources of the TXOP are shared with other APs in the multi-AP group. In one implementation, the AP that acquires the TXOP in the multi-AP group becomes the master AP of the multi-AP group. The master AP can then share a portion (which can be the entire TXOP) of its acquired TXOP with one or more other APs in the multi-AP group.

[0151] OFDMA is a transmission technology introduced in the revision of the IEEE 802.11ax standard. OFDMA provides a multiple access scheme that allows multiple STAs to simultaneously transmit frames using non-overlapping (orthogonal) frequency subcarriers.

[0152] In Coordinated OFDMA (C-OFDMA), an AP (e.g., a master AP) is envisioned to coordinate multi-AP transmissions (which may or may not include a coordinating AP) by allocating appropriate frequency resources (e.g., channels / subchannels) to each of multiple APs for a given transmission period. The coordinating AP may also indicate transmission parameters (e.g., PPDU format, guard interval, symbol duration, etc.) for the multi-AP transmissions. Multiple APs simultaneously access the allocated frequency resources using OFDMA during the transmission period. Figure 10 This illustrates C-OFDMA as a multi-AP channel access method compared to Enhanced Distributed Channel Access (EDCA). For example... Figure 10 As shown, in EDCA, channel access for multiple APs (e.g., AP1, AP2) can occur within consecutive time periods (e.g., TXOP). During a given channel access period, a single AP can use the entire channel (e.g., 80 MHz). Conversely, in C-OFDMA, access for multiple APs (multi-AP channel access) can occur within the same time period (e.g., TXOP) on orthogonal frequency resources. For example, as... Figure 10 As shown, an 80 MHz channel can be divided into four non-overlapping 20 MHz channels, each 20 MHz channel being assigned to a corresponding AP among multiple APs. For example, multiple APs can simultaneously transmit to their respective associated STAs within the same time period.

[0153] It is anticipated that future IEEE 802.11 standard drafts will extend the existing TXS procedure described above to APs. In such a procedure (hereinafter referred to as the inter-AP TXS procedure), an AP (hereinafter referred to as the shared AP) may allocate a portion of its acquired TXOP time to one or more other APs (hereinafter referred to as the shared AP). The shared AP can use the allocated time to communicate with its associated STA and / or other shared APs without being triggered by the shared AP. The shared AP may or may not be part of an AP communicating during the allocated time period.

[0154] Figure 11 This is example 1100 illustrating the TXS process between APs. (Example 1100) Figure 11 As shown, Example 1100 includes APs 1102, 1104, 1106, and 1108. In this example, APs 1102, 1104, 1106, and 1108 can be configured as described above. Figure 9 The document describes a multi-AP group. In one example, AP 1102 can be the master AP in the multi-AP group, while APs 1104, 1106, and 1108 can be slave APs in the multi-AP group. However, the inter-AP TXS procedure described herein is not limited to use in a multi-AP group and / or in the presence of master and slave APs.

[0155] In Example 1100, AP 1102 can acquire a TXOP. AP 1102 can then initiate an inter-AP TXS operation by sending an MRTT frame 1110 to AP 1104. The MRTT frame 1110 can have a format similar to the MU-RTS trigger frame 600 described above. In one example, the MRTT frame 1110 can indicate the identifier of AP 1104 (e.g., in the AID12 subfield of the User Information field of the MRTT frame 1110) and the allocation time 1132 of the TXOP (e.g., in the allocation duration subfield of the User Information field). Additionally, the MRTT frame 1110 can indicate the TXS mode (e.g., in the Triggered TXOP Sharing Mode subfield of the Public Information field of the MRTT frame 1110). The TXS mode can indicate whether AP 1104 should communicate with AP 1102 only during allocation time 1132 (e.g., when TXS mode is set to 1), or whether AP 1104 can communicate with AP 1102 or another STA (e.g., an associated non-AP STA or another AP STA) during allocation time 1132.

[0156] AP 1104 can respond to MRTT frame 1110 by sending CTS frame 1112 to AP 1102. Subsequently, for example, during the short inter-frame interval (SIFS) following the sending of CTS frame 1112, AP 1104 can continue communicating using the allocated time 1132 according to the TXS mode indicated in MRTT frame 1110 without a trigger from AP 1102. In example 1100, the TXS mode allows AP 1104 to communicate with AP 1102 or with another STA during the allocated time 1132. Thus, as Figure 11 As shown, AP 1104 can use allocation time 1132 to send to the associated STA ( Figure 11 (Not shown in the image) Sending (non-TB) downlink (DL) PPDU 1114 and from the associated STA ( Figure 11 (Not shown in the image) Receive uplink (UL) PPDU 1116.

[0157] In one example, with the remaining TXOP time, AP 1102 can initiate another inter-AP TXS operation by sending MRTT frame 1118 to APs 1106 and 1108. MRTT frame 1118 can have a format similar to the MU-RTS trigger frame 600 described above. In this example, MRTT frame 1118 can (e.g., in the corresponding AID12 subfield of the corresponding user information field of MRTT frame 1118) indicate the identifiers of APs 1106 and 1108, and (e.g., in the corresponding allocation duration subfield of the user information field) indicate the allocation time 1134 of the TXOP. Additionally, MRTT frame 1118 can (e.g., in the triggered TXOP sharing mode subfield of the public information field of MRTT frame 1118) indicate the TXS mode. The TXS mode can indicate whether AP 1106 and 1108 should communicate with AP 1102 only during allocation time 1134 (e.g., when TXS mode is set to 1), or whether AP 1106 and 1108 can communicate with AP 1102 or other STAs (e.g., associated non-AP STAs or another AP STA) during allocation time 1134.

[0158] APs 1106 and 1108 can respond to MRTT frame 1118 by sending CTS frames 1120 and 1122 to AP 1102, respectively. Subsequently, for example, during SIFS after sending CTS frames 1120 and 1122, APs 1106 and 1108 can continue without triggering from AP 1102 to communicate using allocation time 1134 according to the TXS mode indicated in MRTT frame 118. In example 1100, the TXS mode may allow APs 1106 and 1108 to communicate with AP 1102 or with another STA during allocation time 1134. Thus, as... Figure 11 As shown, AP 1104 can use allocation time 1134 to allocate to the associated STA ( Figure 11 (Not shown in the image) Sends (non-TB) DL PPDU 1124 and from the associated STA ( Figure 11 (Not shown in the image) receives UL PPDU1128. Similarly, AP 1108 can use allocation time 1134 to send to the associated STA ( Figure 11 (Not shown in the image) Sends (non-TB) DL PPDU 1126 and from the associated STA ( Figure 11 (Not shown in the image) Receives UL PPDU 1130.

[0159] In the example, C-OFDMA can be used for the transmission of DL PPDU 1124 and 1126 and UL PPDU 1128 and 1130. Specifically, AP 1102 can allocate corresponding frequency resources orthogonal to each other for allocation time 1134 to APs 1106 and 1108. For example, AP 1102 can divide an 80 MHz channel into two non-overlapping 40 MHz channels, each allocated to one of APs 1106 and 1108 respectively. In the example, the frequency resources allocated to the APs are indicated in the RU allocation subfield of the user information field (which indicates the identifier of the AP) of MRTT frame 1118. Therefore, DL PPDU 1124 and UL PPDU 1128 can be transmitted on RUs orthogonal to the RUs used for the transmission of DL PPDU 1126 and UL PPDU 1130.

[0160] Figure 12 An example PPDU 1200 is shown that can be used for downlink DL PPDU or UL PPDU. For example, the PPDU 1200 can be... Figure 11 The embodiments described herein include DL PPDU 1114, 1124, or 1126, or UL PPDU 1116, 1128, or 1130. PPDU 1200 can be an Ultra-High Reliability (UHR) PPDU, which can be used by devices modified to conform to the IEEE 802.11bn standard. Such devices can operate in the 2.4, 5, and 6 GHz frequency bands. In one implementation, PPDU 1200 can be transmitted over a bandwidth of up to 320 MHz. PPDU 1200 can be used by devices for both single-user (SU) and multi-user (MU) transmission. Note that UHR can be referred to by different names (e.g., Ultra-High Throughput (UHR) or Ultra-High Efficiency (UHE)).

[0161] like Figure 12 As shown, the PPDU 1200 includes a non-HT short training field (L-STF), a non-HT long training field (L-LTF), a non-high throughput (non-HT) signal field (L-SIG), a non-HT repetitive signal field (RL-SIG), a universal signal field (U-SIG), 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 packet extension (PE) field.

[0162] L-STF is used by the PPDU 1200 receiver to synchronize with the PPDU 1200 transmitter's carrier frequency and frame timing, and to adjust the receiver's signal gain.

[0163] L-LTF is used by the receiver of PPDU 1200 to estimate channel coefficients in order to balance the channel response (e.g., amplitude and phase distortion) in both the signal field (L-SIG, RL-SIG, U-SIG, UHR-SIG) and data field of PPDU 1200.

[0164] L-SIG and RL-SIG contain the parameters needed to demodulate the data field. The L-SIG can be equalized using channel coefficients estimated with L-LTF, and the L-SIG can be demodulated to obtain the demodulation parameters for the data field.

[0165] U-SIG ensures forward compatibility of PPDU 1200. This means that any future PPDUs that are backward compatible with IEEE 802.11bn will contain the same U-SIG field. Therefore, devices compliant with IEEE 802.11bn will be able to understand PPDUs developed in future modifications, provided that those modifications also contain the U-SIG field.

[0166] The UHR-SIG contains an indication of the resource unit (RU) allocation for each STA. The receiving STA can use the indication in the UHR-SIG to locate its payload in the data field of the PPDU 1200.

[0167] The L-SIG, RL-SIG, U-SIG, and UHR-SIG fields can be considered as the PHY header of PPDU 1200.

[0168] The receiver of the PPDU 1200 uses UHR-STF and one or more UHR-LTF to estimate the channel coefficients in order to equalize the channel response (e.g., amplitude and phase distortion) in the data field of the PPDU 1200.

[0169] The data field contains one or more payloads carried by the PPDU 1200. The one or more payloads may include an MPDU.

[0170] The PE field is an extension of the PPDU 1200, designed to give the receiver of the PPDU 1200 sufficient time to respond after receiving the PPDU 1200.

[0171] Figure 13a and Figure 13b Example 1300 is shown, which illustrates the use of... Figure 11 The diagram illustrates potential problems that may arise during the TXS process between APs. For example... Figure 13a and Figure 13bAs shown, Example 1300 includes APs 1102, 1106, and 1108 as described above. As in Example 1100, AP 1102 initiates an inter-AP TXS operation by sending MRTT frame 1118 to APs 1106 and 1108. MRTT frame 1118 may have a format similar to the MU-RTS trigger frame 600 described above. In one example, MRTT frame 1118 may indicate the identifiers of APs 1106 and 1108 (e.g., in the corresponding AID12 subfield of the corresponding user information field of MRTT frame 1118) and the TXOP allocation time 1134 (e.g., in the corresponding allocation duration subfield of the user information field). Additionally, MRTT frame 1118 may indicate the TXS mode (e.g., in the triggered TXOP sharing mode subfield of the common information field of MRTT frame 1118). The TXS mode can indicate whether AP 1106 and 1108 should communicate with AP 1102 only during the allocated time 1134 (e.g., when the TXS mode is set to 1), or whether AP 1106 and 1108 can communicate with AP 1102 or other STAs (e.g., associated non-AP STAs or another AP STA) during the allocated time 1134.

[0172] APs 1106 and 1108 respond to MRTT frame 1118 by sending CTS frames 1120 and 1122 to AP 1102, respectively. Subsequently, for example, during SIFS after sending CTS frames 1120 and 1122, APs 1106 and 1108 can continue without triggering from AP 1102 to communicate using allocation time 1134 according to the TXS mode indicated in MRTT frame 118. In Example 1300, the TXS mode may permit APs 1106 and 1108 to communicate with AP 1102 or with another STA during allocation time 1134. Thus, as... Figure 13a and Figure 13b As shown, AP 1104 can use allocation time 1134 to allocate to the associated STA ( Figure 13a (Not shown in the image) sends DL PPDU 1302 and from the associated STA ( Figure 13b (Not shown in the image) receives UL PPDU1306. Similarly, AP 1108 can use allocation time 1134 to send to the associated STA ( Figure 13a (not shown in the image) sends DLPPDU 1304 and from the associated STA ( Figure 13b (Not shown in the image) Receives UL PPDU 1308.

[0173] In the example, C-OFDMA can be used for the transmission of DL PPDUs 1302 and 1304 and UL PPDUs 1128 and 1130. Specifically, AP 1102 can allocate corresponding frequency resources orthogonal to each other for allocation time 1134 to APs 1106 and 1108. For example, AP 1102 can divide an 80 MHz channel into two non-overlapping 40 MHz channels, each allocated to one of APs 1106 and 1108 respectively. In the example, the frequency resources allocated to the APs are indicated in the RU allocation subfield of the user information field (which indicates the identifier of the AP) of MRTT frame 1118. Therefore, DL PPDU 1302 and UL PPDU 1306 can be transmitted on RUs orthogonal to the RUs used for the transmission of DL PPDU 1304 and UL PPDU 1308.

[0174] Since APs 1106 and 1108 are not triggered by AP 1102 during allocation time 1134, AP 1102 can indicate a first time period within allocation time 1134 for DL ​​transmission and / or a second time period within allocation time 1134 for UL transmission in MRTT frame 1118. APs 1106 and 1108 can use the first time period to transmit DL PPDUs 1302 and 1304, respectively. Similarly, APs 1106 and 1108 can use the second time period to receive UL PPDUs 1306 and 1308, respectively. The first and second time periods help align the timing of DL PPDUs 1302 and 1304 with that of UL PPDUs 1306 and 1308, as... Figure 13b As shown, this reduces potential OFDM symbol misalignment at the receiver receiving one of PPDUs 1302, 1304, 1306, or 1308. OFDM symbol misalignment causes a desynchronization between the boundaries of OFDM symbols received on the first portion of the channel (e.g., the first 40 MHz) and the boundaries of the corresponding OFDM symbols received on the second portion of the channel (e.g., the second 40 MHz). Since the receiver typically receives and processes the entire channel (in the absence of dedicated receive filters for each sub-channel), the receiver may be unable to decode a PPDU in which OFDM symbol misalignment occurs.

[0175] The existing AP-to-AP TXS procedure does not define how AP 1102 can set the first time period and / or the second time period. In one implementation, AP 1102 can set the first time period and / or the second time period equally or according to a predefined configuration (e.g., reproducing fixed DL and / or UL time periods within allocation time 1134). However, this may not match the actual DL / UL communication needs or requirements of APs 1106 and 1108, and may result in suboptimal DL / UL resource allocation. For example, in the case of DL transmission, such as... Figure 13a As shown, AP 1102 can be configured with a first time period for DL ​​transmission in a manner that substantially exceeds the DL transmission requirements of APs 1106 and 1108. Thus, both APs 1106 and 1108 may need to pad to align the transmission periods of DL PPDUs 1302 and 1304 with the first time period. For example, each of DL PDDUs 1302 and 1304 may consist of a first part (e.g., pre-UHR modulation fields, such as L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG) and a second part (e.g., UHR modulation fields, such as UHR-STF, UHR-LTF, data field, and PE field). For example, in the UL case, as... Figure 13b As shown, AP 1102 can be configured with a second time period for UL transmission in a manner that substantially exceeds the UL transmission requirements of APs 1106 and 1108. This allows the corresponding STAs (STAs) transmitting to APs 1106 and 1108 to... Figure 13b(Not shown) Padding may be necessary to align the transmission periods of UL PPDUs 1306 and 1308 with the second time period. For example, each of UL PPDUs 1306 and 1308 may consist of a first part (e.g., pre-UHR modulation fields such as L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG) and a second part (e.g., UHR modulation fields such as UHR-STF, UHR-LTF, data field, and PE field). APs 1106 and 1108 may insert padding bits into the second part (e.g., the data field) of DL PPDUs 1302 and 1304, respectively. This may result in suboptimal utilization of allocation time 1134, and especially the first time period allocated for DL ​​transmission. In another example for the UL case, the first part may include a UHR preamble portion (e.g., pre-UHR modulation fields (L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG) and UHR-STF and UHR-LTF), and the second part may include a data field and a PE field. The corresponding STAs transmitting to APs 1106 and 1108 may insert padding bits into the second part (e.g., the data field) of UL PPDUs 1306 and 1308, respectively. This may result in suboptimal utilization of allocation time 1134, particularly the allocation of the second time period for UL transmission.

[0176] As further described below, embodiments of this disclosure address the aforementioned problems that may occur in inter-AP TXS. In one aspect, a first AP may send a first frame to a second AP indicating DL transmission parameters for DL ​​transmission. The first AP may be a shared AP, and the second AP may also be a shared AP. The DL transmission may be a multi-AP transmission coordinated / initiated by the second AP. The multi-AP transmission may be performed within the allocated time of the TXOP obtained by the second AP. The DL transmission parameters may include parameters that the second AP can use to determine the DL service requirements of the first AP for the DL transmission. In embodiments, the DL transmission parameters may include / indicate one or more of the following: modulation and coding scheme (MCS), bandwidth (BW) size, resource element (RU) size, PPDU type, or number of spatial streams for the DL transmission. In embodiments, the DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information for the DL transmission. The DL transmission may include DL PPDUs. In another aspect, the first AP may send a buffer status report (BSR) to the second AP indicating the DL traffic buffered at the first AP. In one embodiment, the first frame may include a BSR. The second AP can send a second frame to the first AP, which indicates a time period for DL ​​transmission determined based on DL transmission parameters. The second AP can then send DL PPDUs for DL ​​transmission during this time period.

[0177] On the other hand, the first AP may send a first frame to the second AP indicating the UL traffic of a STA associated with the first AP. The UL traffic of the STA may correspond to the traffic buffered at the STA for uplink transmission to the first AP. The first AP may be a shared AP, and the second AP may also be a shared AP. The first AP may receive a second frame from the second AP, which indicates a time period for UL transmission from the STA to the first AP based on the UL traffic. The UL transmission may be part of a C-OFDMA UL transmission. A C-OFDMA UL transmission may include UL transmissions and additional UL transmissions. The additional UL transmissions may be from another STA to the second AP or to a third AP. The C-OFDMA UL transmission may be performed within the allocated time of the TXOP obtained by the second AP. In one embodiment, the first frame may further indicate the UL traffic of another STA associated with the first AP. In another embodiment, the first frame may also indicate UL transmission parameters for the UL transmission. This time period may be further based on the UL transmission parameters. UL transmission parameters may include / indicate one or more of the following: modulation and coding scheme (MCS), bandwidth (BW) size, resource unit (RU) size, PPDU type, or number of spatial streams used for UL transmission. Alternatively, the first AP may receive from the second AP a second frame indicating the duration of a UL PPDU used for UL transmission from the STA to the first AP, as well as transmission parameters for the UL PPDU. Alternatively, the first AP may send to the second AP a first frame indicating UL time resource information and / or UL frequency resource information used for UL transmission. The first AP receives a second frame from the second AP indicating the duration of the UL PPDU used for UL transmission, determined based on the UL time resource information and / or the UL frequency resource information.

[0178] Other aspects and details of the embodiments are presented in the example embodiments described below.

[0179] Figure 14 illustrates an example 1400 of the inter-AP TXS process according to an embodiment. Figure 14a As shown, Example 1400 includes APs 1402, 1404, and 1406. In this example, APs 1402, 1404, and 1406 can be configured as described above. Figure 9 The document describes a multi-AP group. In one example, AP 1402 can be a shared AP (or master AP) in the multi-AP group, while APs 1404 and 1406 can be shared APs (or slave APs) in the multi-AP group. However, the inter-AP TXS procedure described herein is not limited to use in a multi-AP group and / or in the presence of shared APs (or master APs) and shared APs (or slave APs).

[0180] like Figure 14a As shown, Example 1400 can begin by sending frame 1408 from AP 1404 to AP 1402. In this embodiment, frame 1408 may indicate DL transmission parameters for DL ​​transmission. DL transmission may be a multi-AP transmission. Multi-AP transmission may be performed within the allocated time of the TXOP obtained by AP 1402. Multi-AP transmission may be performed in the context of the inter-AP TXS procedure as described above. Multi-AP transmission may or may not include AP 1402. Multi-AP transmission may be a coordinated DL PPDU transmission performed by AP 1402 and one or more of APs 1404 and 1406. Alternatively, as shown in FIG14, multi-AP transmission may be a coordinated DL PPDU transmission performed by APs 1404 and 1406. Coordinated DL PPDU transmission may include C-OFDMA transmission, coordinated spatial reuse (C-SR) transmission, coordinated beamforming (C-BF) transmission, or coordinated joint transmission. Frame 1502 may include a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame. For example... Figure 14b As shown, in one embodiment involving a UL scenario, frame 1408 may indicate UL traffic at a first STA (not shown in Figure 14) associated with AP 1404. The UL traffic at the first STA may correspond to traffic buffered at the first STA for uplink transmission to AP 1404. In one embodiment, the UL traffic at the first STA may correspond to an uplink queue size at the first STA. The uplink queue size may be used for one or more TIDs. In another embodiment, frame 1408 may also indicate UL traffic at another STA (not shown in Figure 14) associated with AP 140.

[0181] DL transmission parameters may include parameters that AP 1402 can use to determine AP 1404's DL service requirements for DL ​​transmission. In one embodiment, DL transmission parameters may include / indicate one or more of the following: MCS, bandwidth (BW) size, RU size, PPDU type, or number of spatial streams (Nss) for DL ​​transmission. In one embodiment, DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information for DL ​​transmission. In an embodiment involving UL transmission, frame 1408 may alternatively or additionally indicate UL transmission parameters for UL transmission from the first STA to AP 1404. UL transmission may be part of a coordinated UL transmission. Coordinated UL transmission may include UL transmission from the first STA to AP 1404 and additional UL transmissions. Additional UL transmissions may be from another STA (not shown in FIG. 14) to AP 1402 or AP 1406. Coordinated UL transmission may be performed within the allocated time of the TXOP obtained by AP 1402. Coordinated UL transmission may be performed within the context of the inter-AP TXS procedure as described above. Coordinated UL transmissions may or may not include AP 1402. Coordinated UL PPDU transmissions may include C-OFDMA transmissions, Coordinated Space Reuse (C-SR) transmissions, Coordinated Beamforming (C-BF) transmissions, or Coordinated Combined Transmissions.

[0182] In one embodiment, where the DL (or UL, if applicable) transmission parameters include / indicate an MCS, frame 1408 may include an MCS index. In another embodiment, in addition to the MCS index, frame 1408 may indicate the PPDU type / format (e.g., HT, HE, VHT, EHT, UHR, etc.). In yet another embodiment, frame 1408 may further indicate the requested bandwidth (e.g., 20 MHz, 40 MHz, etc.) for the DL / UL transmission. In one embodiment, frame 1408 may indicate multiple MCS indices for multiple bandwidth values ​​for the DL / UL transmission.

[0183] In one embodiment, where the DL / UL transmission parameters include / indicate DL time resource allocation information, frame 1408 may include a duration for the DL / UL transmission. This duration may be a requested duration for the DL / UL transmission.

[0184] In one embodiment, where the DL / UL transmission parameters include / indicate DL / UL frequency resource allocation information, frame 1408 may include the RU size / type (e.g., 26-tone RU, 52-tone RU, etc.) for the DL / UL transmission. The RU size / type may be a requested RU size / type for the DL / UL transmission.

[0185] In one embodiment, the DL / UL transmission parameters can be determined by AP 1404. AP 1404 can select DL transmission parameters from a plurality of DL / UL transmission parameters. Multiple DL transmission parameters can be pre-configured in AP 1404. In one example, the DL / UL transmission parameters can be suggested by AP 1404 for DL / UL transmission. For example, the DL / UL transmission parameters can be preferred parameters for DL / UL transmission.

[0186] In one embodiment, frame 1408 may be, for example, a QoS data / empty frame or an action frame. When frame 1408 is a QoS data / empty frame, the QoS data / empty frame may include an Aggregate Control (A-Control) field, which includes DL transmission parameters, such as... Figure 16a As shown. When frame 1408 is an action frame, the action frame may include information elements (or information fields) containing DL transmission parameters. In the UL scenario, as shown in Figure 16B, the Aggregate Control (A-Control) field includes UL traffic volume and / or UL transmission parameters, and when frame 1408 is an action frame, the action frame may include information elements (or information fields) that include UL traffic volume and / or UL transmission parameters. Information elements in, for example... Figure 17a (DL) and Figure 17b As shown in (UL).

[0187] In one embodiment, frame 1408 may also include a DL or UL buffer status report (BSR). The DL / UL BSR may indicate traffic volume for DL ​​transmissions at AP 1404 (for DL ​​cases) or for UL buffers at the first STA (for UL cases). The DL BSR may indicate traffic volume as referenced above. Figure 4 The buffered traffic volume is described (e.g., in the queue size subfield). In one implementation, the buffered traffic may correspond to traffic buffered for DL ​​transmissions at AP 1404 (DL case) or at the first STA (UL case). In another implementation, the buffered traffic may correspond to DL transmissions destined for AP 1404 intended to be served by DL transmissions for DL ​​cases. Additionally or alternatively, the buffered traffic may correspond to DL / UL transmissions buffered for a specific Access Class (AC) or TID.

[0188] In one example, Example 1400 may also include AP 1406 sending frame 1410 to AP 1402. Frame 1410 may be sent before or after frame 1408. In one embodiment, for the DL case, frame 1410 may indicate DL transmission parameters for DL ​​transmission. In one embodiment, for the UL case, frame 1410 may indicate UL traffic of a second STA (not shown in Figure 14) associated with AP 1406. Frame 1410 is similar to frame 1408. The same description of frame 1408 herein applies to frame 1410.

[0189] Subsequently, AP 1402 can acquire the TXOP and initiate an inter-AP TXS operation by sending MRTT frame 1412 to APs 1404 and 1406. MRTT frame 1412 can have a format similar to the MU-RTS trigger frame 600 described above. In the example, MRTT frame 1412 can indicate the identifiers of APs 1404 and 1406 (e.g., in the corresponding AID12 subfield of the corresponding user information field in MRTT frame 1412) and the TXOP allocation time 1414 (e.g., in the corresponding allocation duration subfield of the user information field). Additionally, MRTT frame 1412 can indicate the TXS mode (e.g., in the triggered TXOP sharing mode subfield of the common information field in MRTT frame 1412). The TXS mode can indicate whether AP 1404 and AP 1406 should communicate with AP 1402 only during allocation time 1414 (e.g., when TXS mode is set to 1), or whether AP 1404 and AP 1406 can communicate with AP 1402 or other STAs (e.g., associated non-AP STAs or another APSTA) during allocation time 1414.

[0190] In one embodiment, for the DL case, MRTT frame 1412 may also indicate a time period 1428 within the allocation time 1414 for DL ​​transmission. DL transmission may be a multi-AP transmission. Multi-AP transmission may be performed within the allocation time of the TXOP obtained by AP 1402. Multi-AP transmission may be performed in the context of the inter-AP TXS procedure as described above. Multi-AP transmission may or may not include AP 1402. Multi-AP transmission may be a coordinated DL PPDU transmission performed by AP 1402 and one or more of APs 1404 and 1406. Alternatively, as shown in FIG14, multi-AP transmission may be a coordinated DL PPDU transmission performed by APs 1404 and 1406. Coordinated DL PPDU transmission may include C-OFDMA transmission, coordinated spatial reuse (C-SR) transmission, coordinated beamforming (C-BF) transmission, or coordinated joint transmission. Frame 1502 may include a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame. In one embodiment, DL transmission may respond to frames 1408 and 1410 from AP1404 and AP 1406 respectively by signaling DL transmission parameters for DL ​​transmission.

[0191] In one embodiment for the UL case, MRTT frame 1412 may also indicate a time period 1428 for UL transmission within the allocated time period 1414. UL transmission may be part of a coordinated UL transmission. A coordinated UL transmission may include a UL transmission from a first STA to AP 1404 and additional UL transmissions. Additional UL transmissions may be from another STA to AP 1402 or to AP 1406. Coordinated UL transmissions may be performed within the allocated time of the TXOP obtained by AP 1402. Coordinated UL transmissions may be performed within the context of the inter-AP TXS process as described above. Coordinated UL transmissions may or may not include AP 1402. Coordinated UL PPDU transmissions may include C-OFDMA transmissions, coordinated spatial reuse (C-SR) transmissions, coordinated beamforming (C-BF) transmissions, or coordinated joint transmissions. In one embodiment, UL transmissions may respond to frames 1408 and 1410 from AP 1404 and AP 1406, respectively, each frame signaling UL traffic and / or UL transmission parameters for the UL transmission.

[0192] In one embodiment, AP 1402 may determine time period 1428 based on the DL / UL transmission parameters indicated in frame 1408 and / or the DL / UL transmission parameters indicated in frame 1410.

[0193] In one embodiment, AP 1402 may determine a first data rate for DL / UL transmissions for AP 1404 based on the DL / UL transmission parameters indicated in frame 1408. In one embodiment, AP 1402 may also determine a second data rate for DL ​​transmissions for AP 1406 based on the DL / UL transmission parameters indicated in frame 1410. For example, AP 1402 may determine the first / second data rate based on an MCS index, either alone or in combination with the PPDU type / format, bandwidth value, and / or number of spatial streams indicated in frames 1408 / 1410. For example, the MCS table provided in the IEEE 802.11 standard may be used to determine the first / second data rate.

[0194] In one embodiment, AP 1402 can determine a first duration using a first data rate and traffic volume (e.g., indicated in frame 1408). In the case of DL transmission, this may be traffic volume buffered for transmission at AP 1404. In one embodiment, AP 1402 can determine a second duration using a second data rate and buffered traffic volume (for DL ​​transmission at AP 1406) (e.g., indicated in frame 1410). In one embodiment, AP 1402 may select the larger of the first and second durations as time period 1428. Thus, time period 1428 is guaranteed to be long enough to accommodate DL / UL traffic requirements of both AP 1404 and 1406, or DL / UL traffic requirements indicated by both AP 1404 and 1406. In another embodiment, time period 1428 may withstand the maximum PPDU duration. That is, time period 1428 may not exceed the maximum PPDU duration. In another embodiment, the APs (AP 1420 for DL ​​and AP 1402 for UL) can select the shorter of a first duration and a second duration as time period 1428. This ensures that time period 1428 can be fully used for DL / UL transmissions of data traffic performed / towards both APs 1404 and 1406. In other words, for DL, neither AP 1404 nor AP 1406 needs to add padding to their respective DLPPDUs to align their transmission periods with time period 1428. Similarly, for UL, neither UL PPDUs 1420 nor 1422 needs to include padding bits to align their transmission periods with time period 1428.

[0195] In one embodiment, MRTT frame 1412 may include the duration of time period 1428. In one embodiment, the start time of time period 1428 may be determined based on MRTT frame 1412. For example, the start time of time period 1428 may be 2 SIFS from the time MRTT frame 1412 is received, plus the CTS frame transmission time (optionally, plus the duration of the time period for DL ​​transmission used to allocate time 1414). The end time of time period 1428 may be determined based on the start time and the indicated duration.

[0196] In another embodiment, MRTT frame 1412 may include the start and end times of time period 1428, the start and duration of time period 1428, or the duration and end time of time period 1428. In such an embodiment, the start time of time period 1428 may not be based on MRTT frame 1412.

[0197] In another embodiment, the MRTT frame 1412 may indicate the time period 1428 as a segment of the allocated time 1414. For example, the MRTT frame 1412 may indicate that the time period 1428 corresponds to the first / second half of the allocated time 1414, or the first / last X microseconds of the allocated time 1414, etc.

[0198] In another embodiment, the MRTT frame 1412 can indicate the time period 1428 by indicating the number of OFDM symbols (for a given duration) to be transmitted during the time period 1428.

[0199] In other embodiments, AP 1402 may initiate inter-AP TXS operation by sending frames other than the MRTT frame. For example, AP 1402 may use a multi-AP trigger frame to initiate inter-AP TXS operation. The multi-AP trigger frame may include / indicate the same information as described above included / indicated in the MRTT frame 1412. AP 1404 and AP 1406 may or may not respond to or acknowledge the multi-AP trigger frame from AP 1402.

[0200] like Figure 14aAs shown (for DL), AP 1404 and AP 1406 can respond to MRTT frame 1412 by sending CTS frames 1416 and 1418 to AP 1402, respectively. Subsequently, for example, at SIFS after sending CTS frames 1416 and 1418, AP 1404 and 1406 can continue without triggering from AP 1402 to use allocated time 1414 for communication according to the TXS mode indicated in MRTT frame 1412 and taking into account time period 1428. In example 1400, the TXS mode allows AP 1404 and 1406 to communicate with AP 1402 or with another STA during allocated time period 1414. Thus, as shown in FIG14, AP 1404 can use time period 1428 of allocated time period 1414 to communicate with the associated STA ( Figure 14a (Not shown in the image) Sends (non-TB) DL PPDU 1420. AP 1404 can use the DL transmission parameters indicated in frame 1408 in the transmission of DL PPDU 1420. DL PPDU 1420 has a transmission duration equal to time period 1428. Similarly, AP 1406 can use time period 1428 to send (non-TB) DL PPDU 1420 to the associated STA. Figure 14a (Not shown in the image) Transmit (non-TB) DL PPDU 1422. AP 1404 can use the DL transmission parameters indicated in frame 1410 in the transmission of DL PPDU 1422. DL PPDU 1422 has a transmission duration equal to time period 1428. In example 1400, AP 1406 can insert padding bits into the payload of DL PPDU 1422 to ensure that the transmission duration of PPDU 1422 is equal to time period 1428. However, with time period 1428 set by AP 1402 as described above, AP 1404 does not need to insert any padding bits into DL PPDU 1420 and can use time period 1428 entirely for the transmission of buffered DL data. Therefore, the utilization of allocated time 1414 is increased, especially the time period 1428 allocated for DL ​​transmission.

[0201] like Figure 14bAs shown, for UL, APs 1404 and 1406 can respond to MRTT frame 1412 by sending CTS frames 1416 and 1418 to AP 1402, respectively. Subsequently, for example, at SIFS after sending CTS frames 1416 and 1418, APs 1404 and 1406 can continue without triggering from AP 1402 to communicate using allocation time 1414 according to the TXS mode indicated in MRTT frame 1412 and taking into account time period 1428. In example 1400, the TXS mode allows APs 1404 and AP 1406 to communicate with AP 1402 or with another STA during allocation time 1414. Thus, in one example, as shown in FIG14, AP 1404 can use the first part of allocation time 1414 to communicate with the associated STA ( Figure 14b (Not shown in Figure 14) sends (non-TB) DL PPDU 1420. Similarly, AP 1406 can use the first portion of allocation time 1414 to send (non-TB) DL PPDU 1422 to the associated STA (not shown in Figure 14). Subsequently, AP 1404 can use the first time period 1428 to send from the first STA associated with AP 1404 (not shown in Figure 14). Figure 14b (Not shown in the image) receives UL PPDU 1424. Similarly, AP 1406 can use the first time period 1428 to receive from the second STA associated with AP 1406 ( Figure 14b (Not shown) Receives UL PPDU 1426. In one example, AP 1404 may send a frame to the first STA during the first portion 1414 of the allocation time to request / trigger UL PPDU 1424. In another example, AP 1406 may send a frame to the second STA during the first portion 1414 of the allocation time to request / trigger UL PPDU 1426. In yet another example, the start time of the first time period 1428 may be aligned with the start time of the allocation time 1414. Therefore, the UL transmission may not precede the DL transmission. The first and second STAs may be triggered by MRTT frame 1412, for example, by sending UL PPDUs 1424 and 1426 respectively.

[0202] In the example related to DL, according to any indication in MRTT frame 1412, AP 1404 can use the remaining duration of allocation time 1414 to receive UL PPDU 1424 from the associated STA (not shown in Figure 14). In the example, according to any indication in MRTT frame 1412, AP 1406 can use the remaining duration of allocation time 1414 to receive UL PPDU 1426 from the associated STA (not shown in Figure 14).

[0203] In embodiments involving UL, the first STA may use the UL transmission parameters indicated in frame 1408 in the transmission of UL PPDU 1424. UL PPDU 1424 has a transmission duration equal to time period 1428. In an embodiment, the second STA may use the UL transmission parameters indicated in frame 1410 in the transmission of UL PPDU 1426. UL PPDU 1426 has a transmission duration equal to time period 1428. In example 1400, the second STA may insert padding bits into the payload of UL PPDU 1426 to ensure that the transmission duration of PPDU 1426 is equal to time period 1428. However, when time period 1428 is set by AP 1402 as described above, the first STA may not need to insert any padding bits into UL PPDU 1424 and may use time period 1428 entirely for transmitting buffered UL data to AP 1404. Therefore, the utilization of allocated time 1414 is increased, and in particular, the time period 1428 allocated for UL transmission is increased.

[0204] In the example, C-OFDMA can be used for the transmission of DL PPDU 1420 and 1422, and UL PPDU 1424 and 1426. Specifically, AP 1402 can allocate corresponding frequency resources orthogonal to each other for allocation time 1414 to APs 1404 and 1406. For example, AP 1402 can divide an 80 MHz channel into two non-overlapping 40 MHz channels, each allocated to one of APs 1404 and 1406 respectively. In the example, the frequency resources allocated to the AP are indicated in the RU allocation subfield of the user information field (which indicates the identifier of the AP) of MRTT frame 1412. Therefore, DL PPDU 1420 and UL PPDU 1424 can be transmitted on RUs orthogonal to the RUs used for the transmission of DL PPDU 1422 and UL PPDU 1426.

[0205] In another embodiment ( Figure 14a(Not shown in the image) AP 1404 may include a DLBSR in frame 1408, but may not include DL transmission parameters in frame 1408. Similarly, AP 1406 may include a DL BSR in frame 1410, but may not include DL transmission parameters in frame 1410. AP 1402 may determine the time period 1428 for DL ​​transmission based on one or both of the DL BSRs received from AP 1404 and 1406. In one example, AP 1402 may further determine DL transmission parameters for DL ​​transmission of one or more of AP 1404 and 1406 based on one or both of the DL BSRs received from AP 1404 and 1406. In embodiments, DL transmission parameters may include an MCS for DL ​​transmission, DL time resource allocation information, DL frequency resource allocation information, or the number of spatial streams. AP 1402 may include the determined DL transmission parameters in MRTT frame 1412. By selecting time period 1428 and DL transmission parameters based on DL BSR, AP 1402 can ensure that at least one of AP 1404 and AP1406 fully utilizes time period 1428 for DL ​​transmission of data services (i.e., without padding).

[0206] In another embodiment, for UL ( Figure 14b (Not shown in the image) AP 1404 may include the UL traffic of the first STA in frame 1408, but may not include the UL transmission parameters for the UL transmission from the first STA to AP 1404 in frame 1408. Similarly, AP 1406 may include the amount of UL traffic for the second STA in frame 1410, but may not include the UL transmission parameters for the UL transmission from the second STA to AP 1406 in frame 1410. AP 1402 may determine the time period 1428 based on one or both of the UL traffic of the first STA and the UL traffic of the second STA. In one example, AP 1402 may further determine the UL transmission parameters for the UL transmission to AP 1404 and / or the UL transmission to AP 1406 based on one or more of the UL traffic of the first STA and the UL traffic of the second STA. In embodiments, the UL transmission parameters may include the MCS for the UL transmission, UL time resource allocation information, UL frequency resource allocation information, or the number of spatial streams. AP 1402 can include the determined UL transmission parameters in MRTT frame 1412. By selecting time period 1428 and UL transmission parameters based on one or more of the UL traffic of the first STA and the second STA, AP 1402 can ensure that at least one of the first STA and the second STA fully utilizes time period 1428 for UL transmission of data services (i.e., without padding).

[0207] Figure 15a and Figure 15b Example 1500 of an inter-AP TXS process according to another embodiment is shown. Figure 15a and Figure 15b As shown, Example 1500 also includes APs 1402, 1404, and 1406 described above with reference to Figure 14. In the example, APs 1402, 1404, and 1406 can be configured as described above. Figure 9 The document describes a multi-AP group. In one example, AP 1402 can be a shared AP (or master AP) in the multi-AP group, while APs 1404 and 1406 can be shared APs (or slave APs) in the multi-AP group. However, the inter-AP TXS procedure described herein is not limited to use in a multi-AP group and / or in the presence of shared APs (or master APs) and shared APs (or slave APs).

[0208] like Figure 15a As shown, Example 1500 (for DL) may begin with AP 1402 sending frame 1502 to AP 1404 and / or AP 1406. In an embodiment, frame 1502 requests a DL BSR from AP 1404 and / or AP 1406 for DL ​​transmission. DL transmission may be a multi-AP transmission. Multi-AP transmission may be performed within the allocated time of the TXOP obtained by AP 1402. Multi-AP transmission may be performed within the context of the inter-AP TXS procedure as described above. Multi-AP transmission may or may not include AP 1402. Multi-AP transmission may be a coordinated DL PPDU transmission performed by AP 1402 and one or more of APs 1404 and 1406. Alternatively, as shown in FIG15, multi-AP transmission may be a coordinated DL PPDU transmission performed by AP 1404 and AP 1406. Coordinated DL PPDU transmissions may include C-OFDMA transmissions, coordinated spatial reuse (C-SR) transmissions, coordinated beamforming (C-BF) transmissions, or coordinated joint transmissions. Frame 1502 may include a Buffer Status Report Polling (BSRP) triggered frame, a basic triggered frame, a polling frame, or a request frame.

[0209] like Figure 5As shown in b, Example 1500 (for UL) may begin with AP 1402 sending frame 1502 to AP 1404 and / or AP 1406. In this embodiment, frame 1502 requests a UL BSR from AP 1404 and / or AP 1406. Coordinated UL transmissions may include a UL transmission from a first STA (not shown in Figure 15) to AP 1404 and additional UL transmissions. Additional UL transmissions may be from another STA (not shown in Figure 15) to AP 1402 or AP 1406. Coordinated UL transmissions may be performed within the allocated time of a TXOP obtained by AP 1402. Coordinated UL transmissions may be performed within the context of an inter-AP TXS procedure as described above. Coordinated UL transmissions may or may not include AP 1402. Coordinated UL PPDU transmissions may include C-OFDMA transmissions, coordinated spatial reuse (C-SR) transmissions, coordinated beamforming (C-BF) transmissions, or coordinated joint transmissions. Frame 1502 may include a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame.

[0210] In embodiments involving DL, AP 1404 can respond to frame 1502 by sending frame 1504 to AP 1402. In an embodiment, frame 1504 includes a DL BSR for DL ​​transmission. The DL BSR can indicate the traffic buffered at AP 1404 for DL ​​transmission. The DL BSR can indicate as referenced above. Figure 4 The buffered traffic volume is described (e.g., in the queue size subfield). In one implementation, the buffered traffic may correspond to all traffic buffered for DL ​​transmissions at AP 1404. In another implementation, the buffered traffic may correspond to DL transmissions destined for a specific STA intended to be served by DL transmissions at AP 1404. Additionally or alternatively, the buffered traffic may correspond to DL transmissions buffered for a specific Access Class (AC) or TID.

[0211] In embodiments involving DL, frame 1504 may also indicate DL transmission parameters for DL ​​transmission. DL transmission parameters may include parameters that AP 1402 can use to determine AP 1404's DL service requirements for DL ​​transmission. In embodiments, DL transmission parameters may include / indicate one or more of the following for DL ​​transmission: MCS, bandwidth (BW) size, RU size, PPDU type, or number of spatial streams (Nss). In embodiments, DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information for DL ​​transmission.

[0212] In embodiments involving UL, AP 1404 may respond to frame 1502 by sending frame 1504 to AP 1402. In one embodiment, frame 1504 may indicate UL traffic at a first STA (not shown in FIG. 15) associated with AP 1404. The UL traffic at the first STA may correspond to the traffic buffered at the first STA for uplink transmission to AP 1404. In one embodiment, the UL traffic at the first STA may correspond to the uplink queue size at the first STA. The uplink queue size may be used for one or more TIDs. In another embodiment, frame 1504 may also indicate UL traffic at another STA (not shown in FIG. 15) associated with AP 1404.

[0213] In embodiments involving UL, frame 1504 may alternatively or additionally indicate UL transmission parameters for the UL transmission from the first STA to AP 1404. The UL transmission may be part of a coordinated UL transmission.

[0214] In embodiments involving DL, where DL transmission parameters include / indicate MCS, frame 1504 may include an MCS index. In another embodiment, in addition to the MCS index, frame 1504 may indicate the PPDU type / format (e.g., HT, HE, VHT, EHT, UHR, etc.). In yet another embodiment, frame 1504 may further indicate the requested bandwidth for DL ​​transmission (e.g., 20 MHz, 40 MHz, etc.). In embodiments, frame 1504 may indicate multiple MCS indices for multiple bandwidth values ​​for DL ​​transmission.

[0215] In embodiments involving UL, where UL transmission parameters include / indicate the MCS, frame 1504 may include an MCS index. In another embodiment, in addition to the MCS index, frame 1504 may indicate the PPDU type / format (e.g., HT, HE, VHT, EHT, UHR, etc.). In yet another embodiment, frame 1504 may further indicate the requested bandwidth for UL transmission (e.g., 20 MHz, 40 MHz, etc.). In an embodiment, frame 1408 may indicate multiple MCS indices for multiple bandwidth values ​​for UL transmission.

[0216] In embodiments where the DL / UL transmission parameters include / indicate DL / UL time resource allocation information, frame 1504 may include a duration for the DL / UL transmission. This duration may be a requested duration for the DL / UL transmission.

[0217] In embodiments where the DL / UL transmission parameters include / indicate DL frequency resource allocation information, frame 1504 may include the RU size / type (e.g., 26-tone RU, 52-tone RU, etc.) for DL / UL transmission. The RU size / type may be the requested RU size / type for DL / UL transmission.

[0218] In this embodiment, the DL / UL transmission parameters can be determined by AP 1404. AP 1404 can select DL / UL transmission parameters from a plurality of DL / UL transmission parameters. Multiple DL / UL transmission parameters can be pre-configured in AP 1404. In one example, the DL / UL transmission parameters can be suggested by AP 1404 for DL / UL transmission. For example, the DL / UL transmission parameters can be preferred parameters for DL / UL transmission.

[0219] In this embodiment, for DL, frame 1504 can be, for example, a QoS data / empty frame or an action frame. When frame 1504 is a QoS data / empty frame, the QoS data / empty frame may include an aggregation control (A-Control) field, which includes DL transmission parameters, such as... Figure 16a As shown. When frame 1504 is an action frame, the action frame may include information elements (or information fields) containing DL transmission parameters. For example, in Figure 17a The information elements are shown in the image.

[0220] For UL, in this embodiment, frame 1504 may be, for example, a QoS data / empty frame or an action frame. When frame 1504 is a QoS data / empty frame, the QoS data / empty frame may include an aggregation control (A-Control) field, which includes UL traffic volume and / or UL transmission parameters, such as... Figure 16b As shown. When frame 1504 is an action frame, the action frame may include information elements (or information fields) that include UL traffic volume and / or UL transmission parameters. For example, in Figure 7 b shows the information element.

[0221] In embodiments involving UL, frame 1504 may include a UL BSR. The UL BSR may indicate the UL traffic volume of the first STA. The UL BSR may indicate as referenced above. Figure 4 The described buffered traffic volume (e.g., in the queue size subfield). In one implementation, the buffered traffic may correspond to all traffic buffered for UL transmission at the first STA. In another implementation, the buffered traffic may correspond to UL transmissions buffered for a specific Access Class (AC) or TID.

[0222] In one example, for DL, example 1500 may also include AP 1406 transmitting frame 1506 to AP 1402. Frame 1506 may be transmitted before or after frame 1504. In embodiments, frame 1506 may indicate DL transmission parameters for DL ​​transmission. Frame 1506 is similar to frame 1504. The same description of frame 1504 herein applies to frame 1506.

[0223] In one example, for UL, example 1500 may also include AP 1406 sending frame 1506 to AP 1402. Frame 1506 may be sent before or after frame 1504. In one embodiment, frame 1506 may indicate UL traffic of a second STA (not shown in Figure 14) associated with AP 1406. Frame 1506 is similar to frame 1504. The same description of frame 1506 herein applies to frame 1504.

[0224] Subsequently, AP 1402 can acquire the TXOP and initiate an inter-AP TXS operation by sending MRTT frame 1508 to APs 1404 and 1406. MRTT frame 1508 can have a format similar to the MU-RTS trigger frame 600 described above. In the example, MRTT frame 1508 can indicate the identifiers of APs 1404 and 1406 (e.g., in the corresponding AID12 subfield of the corresponding user information field in MRTT frame 1508) and the TXOP allocation time 1510 (e.g., in the corresponding allocation duration subfield of the user information field). Additionally, MRTT frame 1508 can indicate the TXS mode (e.g., in the triggered TXOP sharing mode subfield of the public information field in MRTT frame 1508). The TXS mode can indicate whether AP 1404 and 1406 should communicate with AP 1402 only during allocation time 1510 (e.g., when TXS mode is set to 1), or whether AP 1404 and 1406 can communicate with AP 1402 or other STAs (e.g., associated non-AP STAs or another AP STA) during allocation time 1510.

[0225] In an embodiment, the MRTT frame 1508 may also indicate a time period 1524 within the allocation time 1510 for DL ​​or coordinated UL transmission.

[0226] In an embodiment, AP 1402 may determine time period 1524 based on the DL / UL transmission parameters indicated in frame 1504 and / or the DL / UL transmission parameters indicated in frame 1506.

[0227] In an embodiment, AP 1402 may determine a first data rate for DL / UL transmissions of AP 1402 based on the DL / UL transmission parameters indicated in frame 1504. In another embodiment, AP 1402 may also determine a second data rate for DL ​​transmissions of AP 1406 based on the DL / UL transmission parameters indicated in frame 1506. For example, AP 1402 may determine the first / second data rate based on an MCS index, either alone or in combination with the PPDU type / format, bandwidth value, and / or number of spatial streams indicated in frames 1504 / 1506. For example, the MCS table provided in the IEEE 802.11 standard may be used to determine the first / second data rate.

[0228] In a DL implementation, AP 1402 can determine a first duration for the DL transmission using a first data rate and a buffer of traffic for DL ​​transmission at AP 1404 (e.g., indicated in frame 1504). In an implementation, AP 1402 can determine a second duration for the DL transmission using a second data rate and a buffer of traffic for DL ​​transmission at AP 1406 (e.g., indicated in frame 1506). In one implementation, AP 1402 may select the larger of the first and second durations as time period 1524. This ensures that time period 1524 is long enough to accommodate the DL traffic requirements of both AP 1404 and 1406. In another implementation, time period 1524 may withstand the maximum PPDU duration. That is, time period 1524 may not exceed the maximum PPDU duration. In yet another implementation, AP 1402 may select the shorter of the first and second durations as time period 1524. This ensures that time period 1524 can be fully utilized by AP 1404 and 1406 for DL ​​transmission of data traffic. In other words, neither AP 1404 nor 1406 needs to add padding to their respective DLPPDUs to align their transmission periods with time period 1524.

[0229] In one UL implementation, AP 1402 can determine a first duration using a first data rate and the UL traffic volume indicated in frame 1504. In another implementation, AP 1402 can determine a second duration using a second data rate and the traffic volume indicated in frame 1506. In one implementation, AP 1402 can select the larger of the first and second durations as time period 1524. Therefore, time period 1524 is guaranteed to be long enough to accommodate the UL traffic requirements indicated by both APs 1404 and 1406. In another implementation, time period 1524 can withstand the maximum PPDU duration. That is, time period 1524 may not exceed the maximum PPDU duration. In yet another implementation, AP 1402 can select the shorter of the first and second durations as time period 1524. This ensures that time period 1524 can be fully used for UL transmission of data traffic to both APs 1404 and 1406. In other words, neither UL PPDUs 1520 nor 1522 need to include padding bits to align their transmission periods with time period 1524.

[0230] In an embodiment, MRTT frame 1508 may include the duration of time period 1524. In an embodiment, the start time of time period 1524 may be determined based on MRTT frame 1508. For example, the start time of time period 1524 may be 2 SIFS from the time MRTT frame 1508 is received, plus the CTS frame transmission time (optionally, plus the duration of the time period used for DL ​​transmission to allocate time 1510, in the case of UL transmission). The end time of time period 1524 may be determined based on the start time and the indicated duration.

[0231] In another embodiment, MRTT frame 1508 may include the start and end times of time period 1524, the start and duration of time period 1524, or the duration and end time of time period 1524. In such an embodiment, the start time of time period 1524 may not be based on MRTT frame 1508.

[0232] In another embodiment, the MRTT frame 1508 may indicate the time period 1524 as a segment of the allocated time 1510. For example, the MRTT frame 1508 may indicate that the time period 1524 corresponds to the first / second half of the allocated time 1510, or the beginning / end X microseconds of the allocated time 1510, etc.

[0233] In another embodiment, MRTT frame 1508 can indicate time period 1524 by indicating the number of OFDM symbols (for a given duration) to be transmitted during time period 1524.

[0234] In other embodiments, AP 1402 may initiate inter-AP TXS operation by sending frames other than the MRTT frame. For example, AP 1402 may use a multi-AP trigger frame to initiate inter-AP TXS operation. The multi-AP trigger frame may include / indicate the same information as described above included / indicated in the MRTT frame 1508. APs 1404 and 1406 may or may not respond to or acknowledge the multi-AP trigger frame from AP 1402.

[0235] like Figure 15a As shown (for DL), APs 1404 and 1406 can respond to MRTT frame 1508 by sending CTS frames 1512 and 1514 to AP 1402, respectively. Subsequently, for example, at SIFS after sending CTS frames 1512 and 1514, APs 1404 and 1406 can continue without triggering from AP 1402 to communicate using allocated time 1510 according to the TXS mode indicated in MRTT frame 1608 and considering time period 1624. In example 1500, the TXS mode allows APs 1404 and 1406 to communicate with AP 1402 or with another STA during allocated time period 1510. Thus, as Figure 15a As shown, AP1404 can use the time period 1524 of the allocation time 1510 to send to the associated STA ( Figure 15a (Not shown in the image) Sends (non-TB) DL PPDU 1516. AP 1404 can use the DL transmission parameters indicated in frame 1504 in the transmission of DL PPDU 1516. DL PPDU 1516 has a transmission duration equal to time period 1524. Similarly, AP 1406 can use time period 1524 to send to the associated STA ( Figure 15a (Not shown in the image) Transmit (non-TB) DL PPDU 1518. AP 1404 can use the DL transmission parameters indicated in frame 1506 in the transmission of DL PPDU 1518. DL PPDU 1518 has a transmission duration equal to time period 1524. In example 1500, AP 1406 can insert padding bits into the payload of DL PPDU 1518 to ensure that the transmission duration of PPDU 1518 is equal to time period 1524. However, with time period 1524 set by AP 1402 as described above, AP 1404 does not need to insert any padding bits into DL PPDU 1516, and can use time period 1524 entirely for the transmission of buffered DL data. Therefore, the utilization of allocated time 1510 is increased, and in particular, time period 1524 is allocated for DL ​​transmission.

[0236] like Figure 5As shown in b (for UL), AP 1404 and AP 1406 can respond to MRTT frame 1508 by sending CTS frames 1512 and 1514 to AP 1402, respectively. Subsequently, for example, at SIFS after sending CTS frames 1512 and 1514, AP 1404 and 1406 can continue without triggering from AP 1402 to communicate using allocated time 1510 according to the TXS mode indicated in MRTT frame 1608 and considering time period 1624. In example 1500, the TXS mode may allow AP 1404 and AP 1406 to communicate with AP 1402 or with another STA during allocated time period 1510. Thus, in one example, as Figure 5 As shown in b, AP 1404 can use the first part of the allocation time 1510 to allocate to the associated STA ( Figure 5 (not shown in b) sends (non-TB) DL PPDU 1516. Similarly, AP 1406 can use the first portion of allocation time 1510 to send (non-TB) DL PPDU 1518 to the associated STA (not shown in Figure 15). Subsequently, AP 1404 can use the first time period 1524 to send (non-TB) DL PPDU 1518 from the first STA associated with AP 1404. Figure 5 (not shown in b) receives UL PPDU 1520. Similarly, AP 1406 can use the first time period 1524 to receive from the second STA associated with AP 1406 ( Figure 5 (not shown in b) Receives UL PPDU 1522. In one example, AP 1404 may send a frame to the first STA during the first portion 1510 of the allocation time to request / trigger UL PPDU 1520. In one example, AP 1406 may send a frame to the second STA during the first portion of the allocation time 1510 to request / trigger UL PPDU 1522. In another example, the start time of the first time period 1524 may be aligned with the start time of the allocation time 1510. Therefore, the UL transmission may not precede the DL transmission. The first and second STAs may be triggered by MRTT frame 1508, for example, by sending UL PPDUs 1520 and 1522 respectively.

[0237] In the example related to DL, according to any indication in MRTT frame 1508, AP 1404 can use the remaining duration of allocated time 1510 to receive UL PPDU 1520 from the associated STA (not shown in Figure 15). In the example, according to any indication in MRTT frame 1508, AP 1406 can use the remaining duration of allocated time 1510 to receive UL PPDU 1522 from the associated STA (not shown in Figure 15).

[0238] In embodiments involving UL, the first STA may use the UL transmission parameters indicated in frame 1504 in the transmission of UL PPDU 1520. UL PPDU 1520 has a transmission duration equal to time period 1524. In an embodiment, the second STA may use the UL transmission parameters indicated in frame 1506 in the transmission of UL PPDU 1522. UL PPDU 1522 has a transmission duration equal to time period 1524. In example 1500, the second STA may insert padding bits into the payload of UL PPDU 1522 to ensure that the transmission duration of PPDU 1522 is equal to time period 1524. However, when time period 1524 is set by AP 1402 as described above, the first STA may not need to insert any padding bits into UL PPDU 1520 and may use time period 1524 entirely for transmitting buffered UL data to AP 1404. Therefore, the utilization of allocated time 1510 is increased, and in particular, the time period 1524 allocated for UL transmission is increased.

[0239] In the example, C-OFDMA can be used for the transmission of DL PPDU 1516 and 1518 and UL PPDU 1520 and 1522. Specifically, AP 1402 can assign corresponding frequency resources orthogonal to each other for allocation time 1510 to APs 1404 and 1406. For example, AP 1402 can divide an 80 MHz channel into two non-overlapping 40 MHz channels, each allocated to one of APs 1404 and AP 1406. In the example, the frequency resources allocated to the APs are indicated in the RU allocation subfield of the user information field (which indicates the identifier of the AP) of MRTT frame 1508. Therefore, DL PPDU 1516 and UL PPDU 1520 can be transmitted on RUs orthogonal to the RUs used for the transmission of DL PPDU 1518 and UL PPDU 1522.

[0240] In another embodiment involving DL ( Figure 5(not shown in a) AP 1404 may include a DLBSR in frame 1504, but may not include DL transmission parameters in frame 1504. Similarly, AP 1406 may include a DLBSR in frame 1506, but may not include DL transmission parameters in frame 1506. AP 1402 may determine the time period 1524 for DL ​​transmission based on one or both of the DL BSRs received from AP 1404 and AP 1406. In one example, AP 1402 may also determine DL transmission parameters for DL ​​transmission of one or more of AP 1404 and AP 1406 based on one or both of the DL BSRs received from AP 1404 and AP 1406. In embodiments, DL transmission parameters may include an MCS for DL ​​transmission, DL time resource allocation information, DL frequency resource allocation information, or the number of spatial streams. AP 1402 may include the determined DL transmission parameters in MRTT frame 1508. By selecting time period 1524 and DL transmission parameters based on DL BSR, AP 1402 can ensure that at least one of APs 1404 and 1406 fully utilizes time period 1524 for DL ​​transmission of data services (i.e., without padding).

[0241] In another embodiment involving UL ( Figure 5 (not shown in b) AP 1404 may include UL traffic of the first STA in frame 1504, but may not include UL transmission parameters for UL transmissions from the first STA to AP 1404 in frame 1504. Similarly, AP 1406 may include UL traffic of the second STA in frame 1506, but may not include UL transmission parameters for UL transmissions from the second STA to AP 1406 in frame 1506. AP 1402 may determine time period 1524 based on one or both of the UL traffic of the first STA and the UL traffic of the second STA. In one example, AP 1402 may also determine UL transmission parameters for UL transmissions to AP 1404 and / or to AP 1406 based on one or more of the UL traffic of the first STA and the UL traffic of the second STA. In embodiments, UL transmission parameters may include MCS for UL transmissions, UL time resource allocation information, UL frequency resource allocation information, or number of spatial streams. AP 1402 can include the determined UL transmission parameters in MRTT frame 1508. By selecting time period 1524 and UL transmission parameters based on one or more of the UL traffic of the first STA and the second STA, AP 1402 can ensure that at least one of the first STA and the second STA fully utilizes time period 1524 for UL transmission of data services (i.e., without padding).

[0242] Figure 16a Example A-control fields 1602 and 1604 that can be used in embodiments are shown. A-control fields 1602 and 1604 can be used to carry DL transmission parameters and / or DL ​​BSRs in QoS data / empty frames. As shown in FIG16, A-control fields 1602 and 1604 may include a control ID field indicating the type of A-control fields 1602 and 1604. In one example, the control ID field may indicate that A-control fields 1602 and 1604 include a BSR (“C-BSR”) for DL ​​coordinated transmission. In an embodiment, A-control field 1602 includes a DL Tx parameter field and a queue size field. The DL Tx parameter field indicates the DL transmission parameters as described above. The queue size field includes the DL BSR. In an embodiment, A-control field 1604 includes a DL time resource allocation field and a DL frequency resource allocation field. The DL time resource allocation field may include / indicate the duration for DL ​​coordinated transmission. The DL frequency resource allocation field may include / indicate the RU size / type (e.g., 26-frequency modulation RU, 52-frequency modulation RU, etc.) for coordinated DL transmission.

[0243] Figure 16b Example A-control fields 1602 and 1604 that can be used in embodiments are shown. A-control fields 1602 and 1604 can be used to carry UL transmission parameters and / or UL traffic for the STA in QoS data / empty frames. As shown in FIG16, A-control fields 1602 and 1604 may include a control ID field indicating the type of A-control fields 1602 and 1604. In one example, the control ID field may indicate that A-control fields 1602 and 1604 include a BSR (“C-BSR”) for UL coordinated transmission. In an embodiment, A-control field 1602 includes a UL Tx parameter field and a UL traffic field. The UL Tx parameter field indicates the UL transmission parameters as described above. The UL traffic field indicates the UL traffic for the STA. In an embodiment, A-control field 1604 includes a UL time resource allocation field and a UL frequency resource allocation field. The UL time resource allocation field may include / indicate the duration for UL coordinated transmission. The UL frequency resource allocation field may include / indicate the RU size / type (e.g., 26-tone RU, 52-tone RU, etc.) for coordinated UL transmissions.

[0244] Figure 17a and Figure 17b Example information elements 1702 and 1704 that can be used in embodiments are shown. Information elements 1702 and 1704 can be used to carry DL / UL transmission parameters and / or DL ​​BSR (or UL traffic of STA) in the action frame. Figure 17a and Figure 17b As shown, information elements 1702 and 1704 may include an element ID field, a length field, and an element ID extension field. The element ID and element ID extension fields indicate the type of information elements 1702 and 1704. In one example, the element ID and element ID extension fields may indicate that information elements 1702 and 1704 include a BSR (“C-BSR”) for DL ​​or UL coordinated transmission. In an embodiment, information element 1702 also includes a DL / UL Tx parameter field and a queue size (or UL traffic volume) field. As described above, the DL / UL Tx parameter field indicates DL / UL transmission parameters. The UL traffic queue size / volume field indicates the DL BSR or UL traffic volume for STA. In an embodiment, information element 1704 also includes a DL / UL time resource allocation field and a DL / UL frequency resource allocation field. The DL / UL time resource allocation field may include / indicate the duration for DL / UL coordinated transmission. The DL / UL frequency resource allocation field may include / indicate the RU size / type (e.g., 26-tone RU, 52-tone RU, etc.) for coordinated DL / UL transmission.

[0245] Figure 18 An example process 1800 according to an embodiment is shown. Example process 1800 can be executed by a first AP (such as AP 1402 described above). Figure 18 As shown, process 1800 includes steps 1802 and 1804.

[0246] For the DL (Deep Link) scenario, step 1802 includes the first AP receiving a first frame from the second AP indicating DL transmission parameters for DL ​​transmission. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The first AP may be the master AP of the multi-AP group, and the second AP may be a slave AP of the multi-AP group.

[0247] In the UL case, step 1802 includes: the first AP receiving a first frame from the second AP indicating the UL traffic of the STA associated with the second AP. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The first AP may be the master / shared AP of the multi-AP group, and the second AP may be a slave / shared AP of the multi-AP group. The UL traffic of the STA may correspond to the traffic buffered at the STA for uplink transmission to the second AP.

[0248] In this embodiment, DL transmission is a multi-AP transmission including a second AP. Multi-AP transmission can be coordinated / initiated by a first AP. Multi-AP transmission may or may not include the first AP. Multi-AP transmission may include a third AP. Multi-AP transmission can be C-OFDMA transmission, C-SR transmission, C-BF, or coordinated joint transmission.

[0249] In one embodiment, the DL transmission parameters are selected by the second AP from a plurality of DL transmission parameters. In another embodiment, the DL transmission parameters are suggested by the second AP for DL ​​transmission. In yet another embodiment, the second AP preferably uses the DL transmission parameters for DL ​​transmission.

[0250] In embodiments, DL transmission parameters may include / indicate one or more of the following: MCS, bandwidth (BW) size, RU size, PPDU type, or number of spatial streams (Nss) used for DL ​​transmission. In embodiments, DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information used for DL ​​transmission. DL time resource allocation information may indicate the duration of DL transmission. DL frequency resource allocation information may include the RU size used for DL ​​transmission.

[0251] In one embodiment, the first frame includes an action frame. The action frame may include information elements containing DL transmission parameters. In another embodiment, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field containing DL transmission parameters.

[0252] Step 1804 includes sending a second frame from the first AP to the second AP, the second frame indicating a time period for DL ​​transmission determined based on DL transmission parameters for DL, and indicating a time period for UL transmission from the STA to the second AP based on UL traffic volume.

[0253] In an embodiment, the DL transfer is a multi-AP transfer performed within the context of the inter-AP TXS procedure as described above. For example, the DL transfer can be performed within a TXOP obtained by a first AP. Therefore, the first AP can be a shared AP, and the second AP can also be a shared AP. In such an embodiment, the first frame may also indicate the allocation time of the TXOP obtained by the first AP. The first frame may also indicate an identifier of the second AP, which indicates that the allocation time is shared with the second AP. For UL, in one embodiment, the second frame also indicates the allocation time of the TXOP obtained by the first AP.

[0254] In an embodiment, for DL, the second frame includes an MRTT frame or a multi-AP trigger frame.

[0255] In an embodiment, for DL, the first frame may further include a DL BSR. The DL BSR may indicate DL traffic buffered at the second AP. In an embodiment, the time period for DL ​​transmission is also based on the DL BSR. For UL, in an embodiment, the time period is within the allocated time of the TXOP.

[0256] In this embodiment, the first frame also indicates UL transmission parameters for UL transmission. UL transmission parameters may be selected, suggested, and / or preferred for UL transmission by a second AP. UL transmission parameters may include one or more of the following: MCS, bandwidth size, RU size, PPDU type, or number of spatial streams for UL transmission.

[0257] In this embodiment, the time period is also based on UL transmission parameters.

[0258] In this embodiment, the UL transmission includes a UL PPDU. In this embodiment, the time period includes the duration of the UL PPDU. The UL PPDU may be part of a C-OFDMA UL transmission. The C-OFDMA UL transmission may include both UL transmissions and additional UL transmissions. Additional UL transmissions may be from another STA to a first AP or to a third AP. The C-OFDMA UL transmission may be performed within the allocated time of the TXOP obtained by the first AP.

[0259] In embodiments involving DL, process 1800 may further include sending a third frame from the first AP to the second AP, the third frame requesting a DL BSR for DL ​​transmission from the second AP. The third frame may include a BSRP trigger frame, a basic trigger frame, a polling frame, or a request frame. In one embodiment, process 1800 may further include the first AP receiving a first frame from the second AP in response to the third frame.

[0260] In embodiments involving UL, the first frame includes a UL BSR for the STA, which indicates the UL traffic of the STA. In an embodiment, process 1800 may further include: a third frame requesting a UL BSR being sent from a first AP to a second AP; and a first frame responding to the third frame being received by the first AP from the second AP. In one embodiment, the third frame includes a BSRP trigger frame, a basic trigger frame, a polling frame, or a request frame. In an embodiment, the UL BSR is a C-OFDMA BSR.

[0261] In embodiments involving UL, the second frame includes an MRTT frame or a multi-AP trigger frame. Optionally, the second frame may also indicate an identifier for the second AP.

[0262] In an embodiment involving UL, the first frame includes an action frame. The action frame may include information elements that include the UL traffic of the STA. In another embodiment, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field that includes the UL traffic of the STA.

[0263] Figure 19 Another example process 1900 according to an embodiment is shown. Example process 1900 can be executed by a first AP (such as AP 1402 described above). Figure 19 As shown, process 1900 includes steps 1902 and 1904.

[0264] Step 1902 includes receiving a first frame from the second AP by the first AP, the first frame indicating a DL BSR for DL ​​transmission or UL traffic for UL for a STA associated with the second AP. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The first AP may be the master / shared AP of the multi-AP group, and the second AP may be a slave / shared AP of the multi-AP group. The DL BSR may indicate DL traffic buffered at the second AP for DL, or for UL, the UL traffic of the STA may correspond to traffic buffered at the STA for uplink transmission to the second AP.

[0265] In embodiments targeting DL, DL transmission is a multi-AP transmission including a second AP. The multi-AP transmission can be coordinated / initiated by a first AP. The multi-AP transmission may or may not include the first AP. The multi-AP transmission may include a third AP. The multi-AP transmission can be C-OFDMA transmission, C-SR transmission, C-BF, or coordinated joint transmission.

[0266] Step 1904 includes: in the case of DL, the first AP sends a second frame to the second AP, the second frame indicating: the time period for DL ​​transmission; and DL transmission parameters of the second AP for DL ​​transmission. In the case of UL, step 1904 includes: the first AP sending a second frame to the second AP, the second frame indicating: the duration of the UL PPDU for UL transmission from the STA to the second AP; and transmission parameters for the UL PPDU.

[0267] A UL PPDU can be part of a C-OFDMA UL transmission. A C-OFDMA UL transmission can include UL transmissions and additional UL transmissions. Additional UL transmissions can be from another STA to a first AP or to a third AP. In one embodiment, the second frame also indicates the allocation time of the TXOP obtained by the first AP. The C-OFDMA UL transmission can be performed within the allocation time of the TXOP obtained by the first AP.

[0268] In one embodiment, DL transmission parameters may include / indicate one or more of the following: MCS, bandwidth (BW) size, RU size, PPDU type, or number of spatial streams (Nss) used for DL ​​transmission. In one embodiment, DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information used for DL ​​transmission. DL time resource allocation information may indicate the duration used for DL ​​transmission. DL frequency resource allocation information may include the RU size used for DL ​​transmission.

[0269] In one embodiment, at least one of the time period of the second AP used for DL ​​transmission and the DL transmission parameters is determined based on the DL BSR.

[0270] UL transmission parameters may include one or more of the following: MCS used for UL transmission, bandwidth size, RU size, PPDU type, or number of spatial streams.

[0271] In an embodiment, as described above, a DL transmission is a multi-AP transmission performed within the context of an inter-AP TXS process. For example, a DL transmission can be performed within a TXOP obtained by a first AP. Therefore, the first AP can be a shared AP, and the second AP can also be a shared AP. In such an embodiment, the first frame may also indicate the allocation time of the TXOP obtained by the first AP. The first frame may also indicate an identifier of the second AP, which indicates that the allocation time is shared with the second AP. In an UL embodiment, the frame includes an MRTT frame or a multi-AP trigger frame. In one embodiment, the second frame also indicates an identifier of the second AP.

[0272] In one embodiment, the first frame includes a UL BSR for the STA, which indicates the UL traffic of the STA. In one embodiment, process 1900 may further include: a first AP sending a third frame requesting a UL BSR to a second AP; and the first AP receiving a first frame in response to the third frame from the second AP. In one embodiment, the third frame includes a BSRP trigger frame, a basic trigger frame, a polling frame, or a request frame. In one embodiment, the UL BSR is a C-OFDMA BSR.

[0273] Figure 20 Another example process 2000 according to an embodiment for DL ​​is shown. Example process 200 can be executed by a first AP (such as AP 1404 or 1406 described above). Figure 20 As shown, process 2000 includes steps 2002 and 2004.

[0274] For DL, step 2002 includes sending a first frame from the first AP to the second AP indicating DL transmission parameters for DL ​​transmission. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The first AP may be a slave AP of the multi-AP group, while the second AP may be the master AP of the multi-AP group.

[0275] In embodiments targeting DL, DL transmission is a multi-AP transmission including a first AP. The multi-AP transmission may be coordinated / initiated by a second AP. The multi-AP transmission may or may not include a second AP. The multi-AP transmission may include a third AP. The multi-AP transmission may be a C-OFDMA transmission, a C-SR transmission, a C-BF transmission, or a coordinated joint transmission.

[0276] In one embodiment, for DL, the DL transmission parameters are selected by the first AP from a plurality of DL transmission parameters. In another embodiment, the DL transmission parameters are suggested by the first AP for DL ​​transmission. In yet another embodiment, the first AP preferentially uses the DL transmission parameters for DL ​​transmission.

[0277] In embodiments targeting DL, DL transmission parameters may include / indicate one or more of the following: MCS, bandwidth (BW) size, RU size, PPDU type, or number of spatial streams (Nss) used for DL ​​transmission. In one embodiment, DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information used for DL ​​transmission. DL time resource allocation information may indicate the duration used for DL ​​transmission. DL frequency resource allocation information may include the RU size used for DL ​​transmission.

[0278] In a DL implementation, the first frame includes an action frame. The action frame may include information elements containing DL transmission parameters. In another implementation, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field containing DL transmission parameters.

[0279] Step 2004 includes: receiving a second frame from the second AP by the first AP, indicating a time period for DL ​​transmission determined based on DL transmission parameters.

[0280] In embodiments targeting DL, DL transmission is a multi-AP transmission performed within the context of an inter-AP TXS process, as described above. For example, DL transmission can be performed within a TXOP obtained by a second AP. Thus, the first AP can be a shared AP, and the second AP can also be a shared AP. In such an embodiment, the first frame may also indicate the allocation time of the TXOP obtained by the second AP. The first frame may also indicate an identifier of the first AP, which indicates that the allocation time is shared with the first AP.

[0281] In embodiments targeting DL, the second frame includes an MRTT frame or a multi-AP trigger frame.

[0282] In embodiments targeting DL, the first frame may also include a DL BSR. The DL BSR may indicate DL traffic buffered at the first AP. In one embodiment, the time period for DL ​​transmission is also based on the DL BSR.

[0283] In an embodiment targeting DL, process 2000 may further include: a first AP receiving a third frame from a second AP, the third frame requesting a DL BSR for DL ​​transmission from the first AP. The third frame may include a BSRP trigger frame, a basic trigger frame, a polling frame, or a request frame. In one embodiment, process 2000 may further include: the first AP sending a first frame to the second AP in response to the third frame.

[0284] In an embodiment targeting DL, process 2000 may further include: the first AP using DL transmission parameters and sending a PPDU during the time period used for DL ​​transmission. For example, a PPDU may be sent to a STA associated with the first AP.

[0285] Figure 20 Another example process 2000 according to an embodiment of UL is also shown. Example process 2000 can be performed by a first AP (such as AP 1402 described above). Figure 20 As shown, process 2000 includes steps 2002 and 2004.

[0286] For UL, step 2002 includes: the first AP receiving a first frame from the second AP indicating UL time resource information and / or UL frequency resource information for UL transmission from the STA to the second AP. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The first AP may be the master / shared AP of the multi-AP group, and the second AP may be a slave / shared AP of the multi-AP group. The STA may be associated with the second AP.

[0287] UL transmissions can be part of C-OFDMA UL transmissions. C-OFDMA UL transmissions can include UL transmissions and additional UL transmissions. Additional UL transmissions can be from another STA to the first AP or to a third AP.

[0288] For UL, step 2004 includes the first AP sending a second frame to the second AP indicating the duration of the UL PPDU used for UL transmission, which is determined based on UL time resource information and / or UL frequency resource information.

[0289] In the embodiment for UL, the second frame also indicates the allocation time of the TXOP obtained by the first AP. C-OFDMA UL transmission can be performed within the allocation time of the TXOP obtained by the first AP.

[0290] In an embodiment targeting UL, UL time resource information is preferred / recommended / selected by a second AP. In one embodiment, the UL time resource information includes the length of the UL PPDU.

[0291] In the embodiment targeting UL, UL frequency resource information is preferred / recommended / selected by the second AP. In this embodiment, the UL frequency resource information includes the size of the frequency RU used for UL transmission.

[0292] In embodiments targeting UL, the second frame includes an MRTT frame or a multi-AP trigger frame. In one embodiment, the second frame also indicates an identifier for a second AP.

[0293] In an embodiment targeting UL, the first frame includes an action frame. The action frame may include information elements that include UL time resource information and / or UL frequency resource information. In another embodiment, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field that includes UL time resource information and / or UL frequency resource information.

[0294] Figure 21 Another example process 2100 according to embodiments for DL ​​and UL is shown. Example process 2100 can be performed by a first AP (such as AP 1404 or AP 1406 described above). Figure 21 As shown, process 2100 includes steps 2102 and 2104.

[0295] For DL, step 2102 includes sending a first frame from the first AP to the second AP indicating the DL BSR for DL ​​transmission. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The first AP may be a slave AP of the multi-AP group, while the second AP may be the master AP of the multi-AP group. The DL BSR may indicate DL traffic buffered at the first AP.

[0296] In embodiments targeting DL, DL transmission is a multi-AP transmission including a first AP. The multi-AP transmission may be coordinated / initiated by a second AP. The multi-AP transmission may or may not include a second AP. The multi-AP transmission may include a third AP. The multi-AP transmission may be a C-OFDMA transmission, a C-SR transmission, a C-BF transmission, or a coordinated joint transmission.

[0297] Step 2104 includes: receiving a second frame from the second AP by the first AP, the second frame indicating: a time period for DL ​​transmission; and DL transmission parameters for the first AP to perform DL transmission.

[0298] In embodiments targeting DL, DL transmission parameters may include / indicate one or more of the following: MCS, bandwidth (BW) size, RU size, PPDU type, or number of spatial streams (Nss) used for DL ​​transmission. In one embodiment, DL transmission parameters may include / indicate DL time resource allocation information and / or DL ​​frequency resource allocation information used for DL ​​transmission. DL time resource allocation information may indicate the duration used for DL ​​transmission. DL frequency resource allocation information may include the RU size used for DL ​​transmission.

[0299] In the embodiment for DL, at least one of the time period for the first AP to perform DL transmission and the DL transmission parameters is determined based on the DL BSR.

[0300] In embodiments targeting DL, DL transmission is a multi-AP transmission performed within the context of the inter-AP TXS procedure as described above. For example, DL transmission can be performed within a TXOP obtained by a second AP. Thus, the first AP can be a shared AP, and the second AP can also be a shared AP. In such an embodiment, the first frame may also indicate the allocation time of the TXOP obtained by the second AP. The first frame may also indicate an identifier of the first AP, which indicates that the allocation time is shared with the first AP.

[0301] In an embodiment targeting DL, process 2100 may further include: the first AP using DL transmission parameters and sending a PPDU during the time period of DL transmission. For example, a PPDU may be sent to a STA associated with the first AP.

[0302] In the case of UL, example process 2100 can be performed by a first AP (such as AP 1404 or AP 1406 mentioned above). Figure 21 As shown, process 2100 includes steps 2102 and 2104.

[0303] For UL, step 2102 includes: sending a first frame from the first AP to the second AP indicating the UL traffic of the STA associated with the first AP. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The second AP may be the master / shared AP of the multi-AP group, while the first AP may be a slave / shared AP of the multi-AP group. The UL traffic of the STA may correspond to the traffic buffered at the STA for uplink transmission to the first AP.

[0304] For UL, step 2104 includes: receiving a second frame from the second AP by the first AP, the second frame indicating a time period based on UL traffic for UL transmission from the STA to the first AP.

[0305] In an embodiment targeting UL, the second frame also indicates the allocation time of the TXOP obtained by the second AP. In one embodiment, this time period is within the allocation time of the TXOP.

[0306] In one embodiment, the first frame also indicates UL transmission parameters for UL transmission. UL transmission parameters may be selected, suggested, and / or preferred by the first AP for UL transmission. UL transmission parameters may include one or more of the following: MCS for UL transmission, bandwidth size, RU size, PPDU type, or number of spatial streams.

[0307] In the UL-specific implementation, the time period is also based on UL transmission parameters.

[0308] In embodiments targeting UL, the UL transmission includes a UL PPDU. In one embodiment, the time period includes the duration of the UL PPDU. The UL PPDU may be part of a C-OFDMA UL transmission. The C-OFDMA UL transmission may include both UL transmissions and additional UL transmissions. The additional UL transmission may be from another STA to a second AP or to a third AP. The C-OFDMA UL transmission may be performed within the allocated time of the TXOP obtained by the second AP.

[0309] In an embodiment targeting UL, the first frame includes a UL BSR for the STA, which indicates the UL traffic of the STA. In one embodiment, process 2100 may further include: receiving a third frame requesting a UL BSR from a second AP by a first AP; and in response to the third frame, sending the first frame to the second AP. In one embodiment, the third frame includes a BSRP trigger frame, a basic trigger frame, a polling frame, or a request frame. In one embodiment, the UL BSR is a C-OFDMA BSR.

[0310] In one embodiment, the second frame includes an MRTT frame or a multi-AP trigger frame. In one embodiment, the second frame also indicates the identifier of the first AP.

[0311] In an embodiment targeting UL, the first frame includes an action frame. The action frame may include information elements that include the UL traffic of the STA. In another embodiment, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field that includes the UL traffic of the STA.

[0312] Figure 22Another example process 2200 according to one embodiment is shown. Example process 2200 can be executed by a first AP (such as AP 1404 or AP 1406 described above). Figure 22 As shown, process 2200 includes steps 2202 and 2204.

[0313] Step 2202 includes: sending a first frame from the first AP to the second AP indicating UL traffic for a STA associated with the first AP. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The second AP may be a master / shared AP of the multi-AP group, while the first AP may be a slave / shared AP of the multi-AP group. The UL traffic of the STA may correspond to traffic buffered at the STA for uplink transmission to the first AP.

[0314] Step 2204 includes: receiving a second frame from the second AP by the first AP, the second frame indicating: the duration of the UL PPDU for UL transmission from the STA to the first AP; and transmission parameters for the UL PPDU.

[0315] A UL PPDU can be part of a C-OFDMA UL transmission. A C-OFDMA UL transmission can include UL transmissions and additional UL transmissions. Additional UL transmissions can be from another STA to a second AP or to a third AP. In one embodiment, the second frame also indicates the allocation time of the TXOP acquired by the second AP. The C-OFDMA UL transmission can be performed within the allocation time of the TXOP acquired by the second AP.

[0316] UL transmission parameters may include one or more of the following: MCS used for UL transmission, bandwidth size, RU size, PPDU type, or number of spatial streams.

[0317] In one embodiment, the first frame includes a UL BSR for the STA, the UL BSR indicating the UL traffic of the STA. In one embodiment, process 2200 may further include: receiving a third frame requesting a UL BSR from a second AP by a first AP; and, in response to the third frame, sending the first frame to the second AP. In one embodiment, the third frame includes a BSRP trigger frame, a basic trigger frame, a polling frame, or a request frame. In one embodiment, the UL BSR is a C-OFDMA BSR.

[0318] In one embodiment, the second frame includes an MRTT frame or a multi-AP trigger frame. In one embodiment, the second frame also indicates the identifier of the first AP.

[0319] In one embodiment, the first frame includes an action frame. The action frame may include information elements that include the UL traffic of the STA. In another embodiment, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field that includes the UL traffic of the STA.

[0320] Figure 23 Another example process 2300 according to one embodiment is shown. Example process 2300 can be executed by a first AP (such as AP 1404 or AP 1406 described above). Figure 23 As shown, process 2300 includes steps 2302 and 2304.

[0321] Step 2302 includes: sending a first frame from the first AP to the second AP, indicating UL time resource information and / or UL frequency resource information for UL transmission from the STA to the first AP. In one embodiment, the first AP may be part of a multi-AP group. The multi-AP group may include the second AP. The second AP may be the master / shared AP of the multi-AP group, while the first AP may be a slave / shared AP of the multi-AP group. The STA may be associated with the first AP.

[0322] UL transmissions can be part of C-OFDMA UL transmissions. C-OFDMA UL transmissions can include UL transmissions and additional UL transmissions. Additional UL transmissions can be from another STA to a second AP or to a third AP.

[0323] Step 2304 includes: receiving a second frame from the second AP by the first AP, the second frame indicating the duration of the UL PPDU used for UL transmission determined based on UL time resource information and / or UL frequency resource information.

[0324] In one embodiment, the second frame also indicates the allocation time of the TXOP acquired by the second AP. The C-OFDMA UL transmission can be performed within the allocation time of the TXOP acquired by the second AP.

[0325] In one embodiment, UL time resource information is preferred / recommended / selected by a first AP. In one embodiment, UL time resource information includes the length of the UL PPDU.

[0326] In one embodiment, UL frequency resource information is preferred / recommended / selected by a first AP. In one embodiment, the UL frequency resource information includes the size of the frequency RU used for UL transmission.

[0327] In one embodiment, the second frame includes an MRTT frame or a multi-AP trigger frame. In one embodiment, the second frame also indicates the identifier of the first AP.

[0328] In one embodiment, the first frame includes an action frame. The action frame may include information elements, which include UL time resource information and / or UL frequency resource information. In another embodiment, the first frame includes a QoS empty or data frame. The QoS empty or data frame may include an A-control field, which includes UL time resource information and / or UL frequency resource information.

[0329] Therefore, in one embodiment, there is a method comprising: receiving a first frame from a second AP indicating a modulation and coding scheme (MCS) for downlink (DL) transmission by a first access point (AP); and sending a second frame from the first AP to the second AP indicating an allocation time for a transmission opportunity (TXOP) obtained by the first AP and a time period for DL ​​transmission within the allocation time, wherein the time period is determined based on the MCS.

[0330] In one embodiment, there is also a method comprising: receiving a first frame from a second AP indicating DL transmission parameters for downlink (DL) transmission by a first access point (AP); and sending a second frame from the first AP to the second AP indicating a time period for DL ​​transmission, wherein the time period is determined based on the DL transmission parameters.

[0331] In one embodiment, the DL transmission parameters are selected by the second AP from a plurality of DL transmission parameters.

[0332] In one embodiment, DL transmission parameters are suggested by a second AP for DL ​​transmission.

[0333] In one embodiment, the DL transmission parameters are preferably used by the second AP for DL ​​transmission.

[0334] In one embodiment, DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) for DL ​​transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

[0335] In one embodiment, the second frame also indicates the allocation time of a transmission opportunity (TXOP) obtained by the first AP.

[0336] In one embodiment, the second frame also indicates the identifier of the second AP.

[0337] In one embodiment, DL transmission is a multi-AP transmission that includes a second AP.

[0338] In one embodiment, multi-AP transmission is initiated by the first AP.

[0339] In one embodiment, multi-AP transmission includes a first AP.

[0340] In one embodiment, the first frame includes a downlink (DL) buffer status report (BSR).

[0341] In one embodiment, the time period used for DL ​​transmission is also based on the DL BSR.

[0342] In one embodiment, the DL BSR indicates the DL traffic buffered at the second AP.

[0343] In one embodiment, the first AP sends a third frame to the second AP, which requests a buffer status report (BSR) from the second AP for DL ​​transmission.

[0344] In one embodiment, there is a method comprising: receiving a first frame from a second AP indicating a DL buffer status report (BSR) for downlink (DL) transmission by a first access point (AP); and sending a second frame from the first AP to the second AP indicating the allocation time of a transmission opportunity (TXOP) obtained by the first AP, an identifier of the second AP, a time period for DL ​​transmission, and DL transmission parameters for the second AP to perform DL transmission.

[0345] In one embodiment, at least one of the time period of the second AP used for DL ​​transmission and the DL transmission parameters is determined based on the DL BSR.

[0346] In one embodiment, DL transmission is a multi-AP transmission performed during the TXOP allocation time.

[0347] In one embodiment, multi-AP transmission is coordinated orthogonal frequency division multiple access (C-OFDMA) transmission.

[0348] In one embodiment, DL transmission includes DL Physical Protocol Data Units (PPDUs).

[0349] In one embodiment, the time period of DL transmission includes the length of the DL PPDU.

[0350] In the embodiments, DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) for DL ​​transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

[0351] In one embodiment, there is a method comprising: sending a first frame from a first access point (AP) to a second AP indicating a modulation and coding scheme (MCS) for DL ​​transmission; and receiving from the second AP a second frame from the first AP indicating an allocation time for a transmission opportunity (TXOP) obtained by the second AP and a time period for DL ​​transmission within the allocation time, wherein the time period is determined based on the MCS.

[0352] In one embodiment, there is a method comprising: sending a first frame from a first access point (AP) to a second AP indicating DL transmission parameters for downlink (DL) transmission; and receiving from the second AP a second frame from the first AP indicating a time period for DL ​​transmission, wherein the time period is determined based on the DL transmission parameters.

[0353] In one embodiment, the DL transmission parameters are selected by the first AP from a plurality of DL transmission parameters.

[0354] In one embodiment, DL transmission parameters are suggested by a first AP for DL ​​transmission.

[0355] In one embodiment, DL transmission parameters are preferably used by the first AP for DL ​​transmission.

[0356] In one embodiment, DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) for DL ​​transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

[0357] In one embodiment, DL transmission parameters include downlink (DL) time resource allocation information or DL ​​frequency resource allocation information for DL ​​transmission.

[0358] In one embodiment, DL time resource allocation information indicates the duration of the DL transmission.

[0359] In one embodiment, DL frequency resource allocation information includes resource unit (RU) sizes for DL ​​transmission.

[0360] In one embodiment, the time period used for DL ​​transmission is determined based on DL time resource allocation information or DL ​​frequency resource allocation information.

[0361] In one embodiment, the second frame also indicates the allocation time of a transmission opportunity (TXOP) obtained by the second AP.

[0362] In one embodiment, the second frame includes a multi-user request to send triggered TXOP sharing (MU-RTS TXS) trigger frame or a multi-AP trigger frame.

[0363] In one embodiment, the second frame also indicates the identifier of the first AP.

[0364] In one embodiment, DL transmission is a multi-AP transmission that includes a first AP.

[0365] In one embodiment, multi-AP transmission is initiated by the second AP.

[0366] In one embodiment, multi-AP transmission includes a second AP.

[0367] In one embodiment, multi-AP transmission is coordinated orthogonal frequency division multiple access (C-OFDMA) transmission, coordinated time division multiple access (C-TDMA) transmission, coordinated spatial reuse (C-SR) transmission, coordinated beamforming (C-BF) transmission, or coordinated joint transmission.

[0368] In one embodiment, the first frame includes a downlink (DL) buffer status report (BSR).

[0369] In one embodiment, the time period used for DL ​​transmission is also based on the DL BSR.

[0370] In one embodiment, the DL BSR indicates the DL traffic buffered at the first AP.

[0371] In one embodiment, a third frame is received by a first AP from a second AP, which requests a buffer status report (BSR) from the first AP.

[0372] In one embodiment, the BSR is a Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) BSR.

[0373] In one embodiment, the third frame includes a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame.

[0374] In one embodiment, in response to a third frame, the first AP sends a first frame to the second AP.

[0375] In one embodiment, the first frame includes an action frame.

[0376] In one embodiment, the action frame includes an information element containing DL transmission parameters.

[0377] In one embodiment, the first frame includes a Quality of Service (QoS) empty or data frame.

[0378] In one embodiment, the QoS empty or data frame includes an aggregation control (A-Control) field that includes DL transmission parameters.

[0379] In one embodiment, a first AP uses DL transmission parameters and transmits Physical Layer Protocol Data Units (PPDUs) during the time period used for DL ​​transmission.

[0380] In one embodiment, there is a method comprising: a first frame sent by a first access point (AP) from a second AP, indicating a DL buffer status report (BSR) for downlink (DL) transmission; and a second frame received by the first AP from the second AP, indicating the allocation time of a transmission opportunity (TXOP) obtained by the second AP, an identifier of the first AP, a time period for DL ​​transmission, and DL transmission parameters for the first AP to perform DL transmission.

[0381] In one embodiment, at least one of the time period for DL ​​transmission for the first AP and the DL transmission parameters is determined based on BSR.

[0382] In one embodiment, DL transmission is a multi-AP transmission performed during the TXOP allocation time.

[0383] In one embodiment, multi-AP transmission is coordinated orthogonal frequency division multiple access (C-OFDMA) transmission.

[0384] In one embodiment, DL transmission includes DL Physical Protocol Data Units (PPDUs).

[0385] In one embodiment, the time period of DL transmission includes the length of the DL PPDU.

[0386] In one embodiment, DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) for DL ​​transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

[0387] In one embodiment, there is a computer program product that can be stored on a computer-readable medium and is configured to perform the method according to any of the preceding claims when run on a processor.

[0388] In one embodiment, there is a device arranged to perform, when implemented in a first access point, operations including: receiving from a second AP a first frame indicating a modulation and coding scheme (MCS) for downlink (DL) transmission, and sending to the second AP a second frame indicating the allocation time of a transmission opportunity (TXOP) obtained by the first AP and a time period for DL ​​transmission within the allocation time, wherein the time period is determined based on the MCS.

[0389] In one embodiment, there is a device arranged to perform, when implemented in a first access point, operations including: receiving a first frame from a second access point (AP) indicating DL transmission parameters for downlink (DL) transmission; and sending a second frame to the second AP indicating a time period for DL ​​transmission, wherein the time period is determined based on the DL transmission parameters.

[0390] In one embodiment, there is a device arranged to perform the following operations when implemented in a first access point: sending a first frame to a second AP indicating a modulation and coding scheme (MCS) for DL ​​transmission, and receiving from the second AP a second frame indicating the allocation time of a transmission opportunity (TXOP) obtained by the second AP and a time period for DL ​​transmission within the allocation time, wherein the time period is determined based on the MCS.

[0391] In one embodiment, there is a device arranged to perform, when implemented in a first access point, operations including: sending a first frame to a second AP indicating DL transmission parameters for downlink (DL) transmission; and receiving from the second AP a second frame indicating a time period for DL ​​transmission, wherein the time period is determined based on the DL transmission parameters.

[0392] Therefore, in the uplink scenario, in one embodiment, there is a method comprising: receiving a first frame from a second AP indicating uplink (UL) traffic of a station (STA) associated with the second AP by a first access point (AP); and sending a second frame from the first AP to the second AP indicating the allocation time of a transmission opportunity (TXOP) obtained by the first AP and the time period based on UL traffic and for UL transmissions from the STA to the second AP within the allocation time.

[0393] In one embodiment, there is a method comprising: receiving, by a first access point (AP), a first frame from a second AP indicating uplink (UL) traffic for a station (STA) associated with the second AP; and sending, by the first AP, a second frame to the second AP, the second frame indicating a time period for UL transmission from the STA to the second AP based on the UL traffic.

[0394] In one embodiment, the second frame also indicates the allocation time of a transmission opportunity (TXOP) obtained by the first AP.

[0395] In one embodiment, the first frame also indicates UL transmission parameters for UL transmission.

[0396] In one embodiment, the time period is also based on UL transmission parameters.

[0397] In one embodiment, the UL transmission parameters are selected by the second AP from a plurality of UL transmission parameters.

[0398] In one embodiment, UL transmission parameters are suggested by a second AP for UL transmission.

[0399] In one embodiment, the UL transmission parameters are preferably used by the second AP for UL transmission.

[0400] In one embodiment, UL transmission parameters include one or more of the following: modulation and coding scheme (MCS) for UL transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

[0401] In one embodiment, the first frame includes a UL buffer status report (BSR) for the STA, which indicates the STA's UL traffic volume.

[0402] In one embodiment, there is a third frame from the first AP to the second AP requesting a UL BSR; and the first AP receives a first frame from the second AP in response to the third frame.

[0403] In one embodiment, the third frame includes a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame.

[0404] In one embodiment, the second frame also indicates the identifier of the second AP.

[0405] In one embodiment, there is a method comprising: receiving, by a first access point (AP), a first frame from a second AP indicating uplink (UL) traffic of a station (STA) associated with the second AP; and sending, by the first AP, a second frame to the second AP indicating the allocation time of a transmission opportunity (TXOP) obtained by the first AP, an identifier of the second AP, the duration of an uplink (UL) physical layer protocol data unit (PPDU) for UL transmission from the STA to the second AP during the allocation time; and a modulation and coding scheme (MCS) for the UL PPDU.

[0406] In one embodiment, there is a method comprising: receiving from a second AP a first frame by a first access point (AP) a first frame indicating UL time resource information for uplink (UL) transmission from a STA to the second AP and UL frequency resource information for UL transmission; and a second frame sent from the first AP to the second AP, the second frame indicating: the allocation time of a transmission opportunity (TXOP) obtained by the first AP; an identifier of the second AP; and the duration of a UL physical layer protocol data unit (PPDU) for UL transmission determined based on the UL time resource information and the UL frequency resource information.

[0407] In one embodiment, UL time resource information is preferred / recommended / selected by a second AP.

[0408] In one embodiment, UL time resource information includes the length of the UL PPDU.

[0409] In one embodiment, UL frequency resource information is preferred / recommended / selected by a second AP.

[0410] In one embodiment, UL frequency resource information includes the dimensions of frequency resource units (RUs) used for UL transmission.

[0411] In one embodiment, there is a method comprising: sending a first frame from a first access point (AP) to a second AP, the first frame indicating uplink (UL) traffic at a station (STA) associated with the first AP; and receiving a second frame from the second AP by the first AP, the second frame indicating the allocation time of a transmission opportunity (TXOP) obtained by the second AP, and the time period based on UL traffic and used for UL transmission from the STA to the first AP during the allocation time.

[0412] In one embodiment, there is a method comprising: sending a first frame from a first access point (AP) to a second AP indicating uplink (UL) traffic for a station (STA) associated with the first AP; and receiving from the second AP a second frame from the first AP indicating a time period for UL transmission from the STA to the first AP based on the UL traffic.

[0413] In one embodiment, the second frame also indicates the allocation time of a transmission opportunity (TXOP) obtained by the second AP.

[0414] In one embodiment, the time period is within the allocated time of TXOP.

[0415] In one embodiment, the first frame also indicates UL transmission parameters for UL transmission.

[0416] In one embodiment, the time period is also based on UL transmission parameters.

[0417] In one embodiment, the UL transmission parameters are selected by the first AP from a plurality of UL transmission parameters.

[0418] In one embodiment, UL transmission parameters are suggested by a first AP for UL transmission.

[0419] In one embodiment, the UL transmission parameters are preferably used by the first AP for UL transmission.

[0420] In one embodiment, UL transmission parameters include one or more of the following: modulation and coding scheme (MCS) for UL transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

[0421] In one embodiment, UL transmission includes UL Physical Layer Protocol Data Units (PPDUs).

[0422] In one embodiment, the time period includes the duration of the UL PPDU.

[0423] In one embodiment, the UL PPDU is part of a coordinated orthogonal frequency division multiple access (C-OFDMA) UL transmission.

[0424] In one embodiment, the first frame includes a UL buffer status report (BSR) for the STA, which indicates the STA's UL traffic volume.

[0425] In one embodiment, a third frame requesting a UL BSR is received by a first AP from a second AP, and in response to the third frame, a first frame is sent by the first AP to the second AP.

[0426] In one embodiment, the third frame includes a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame.

[0427] In one embodiment, the UL BSR is a Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) BSR.

[0428] In one embodiment, the second frame includes a multi-user request to send triggered TXOP sharing (MU-RTS TXS) trigger frame or a multi-AP trigger frame.

[0429] In one embodiment, the second frame also indicates the identifier of the first AP.

[0430] In one embodiment, the first frame includes an action frame.

[0431] In one embodiment, the action frame includes an information element that includes the UL traffic volume of the STA.

[0432] In one embodiment, the first frame includes a Quality of Service (QoS) empty or data frame.

[0433] In one embodiment, the QoS empty or data frame includes an aggregation control (A-Control) field that includes the UL traffic of the STA.

[0434] In one embodiment, a trigger frame is sent from a first AP to a STA, and a UL transmission in response to the trigger frame is received from the STA by the first AP during the time period.

[0435] In one embodiment, there is a method that includes: A first frame indicating uplink (UL) traffic for a station (STA) associated with the first AP is sent from the first access point (AP) to the second AP; and The first AP receives a second frame from the second AP, the second frame indicating: the allocation time of the transmission opportunity (TXOP) obtained by the second AP, the identifier of the first AP, the duration of the uplink (UL) physical layer protocol data unit (PPDU) from the STA to the first AP during the allocation time; and the modulation and coding scheme (MCS) for the UL PPDU.

[0436] In one embodiment, there is a method comprising: sending a first frame from a first access point (AP) to a second AP, the first frame indicating UL time resource information and UL frequency resource information for uplink (UL) transmission from a STA to the first AP; and receiving a second frame from the second AP by the first AP, the second frame indicating: the allocation time of a transmission opportunity (TXOP) obtained by the second AP, an identifier of the first AP; and the duration of a UL physical layer protocol data unit (PPDU) for UL transmission determined based on the UL time resource information and the UL frequency resource information.

[0437] In one embodiment, UL time resource information is preferred / recommended / selected by a first AP.

[0438] In one embodiment, UL time resource information includes the length of the UL PPDU.

[0439] In one embodiment, UL frequency resource information is preferred / recommended / selected by the first AP.

[0440] In one embodiment, UL frequency resource information includes the dimensions of frequency resource units (RUs) used for UL transmission.

[0441] In one embodiment, there is a computer program product that can be stored on a computer-readable medium and is arranged to perform the method of any one of claims 1-49 when run on a processor.

[0442] In one embodiment, there is a device arranged to perform operations when implemented in an access point, the operations including: receiving a first frame from a second AP by a first access point (AP), the first frame indicating uplink (UL) traffic for a station (STA) associated with the second AP; and sending a second frame from the first AP to the second AP, the second frame indicating: the allocation time of a transmission opportunity (TXOP) obtained by the first AP; and the time period based on UL traffic and used for UL transmission from the STA to the second AP within the allocation time.

[0443] In one embodiment, there is a device arranged to perform, when implemented in an access point, operations including: receiving a first frame from a second AP by a first access point (AP), the first frame indicating uplink (UL) traffic for a station (STA) associated with the second AP; and sending a second frame from the first AP to the second AP, the second frame indicating a time period for UL transmission from the STA to the second AP based on the UL traffic.

[0444] In one embodiment, there is a device arranged to perform, when implemented in an access point, operations including: receiving from a second AP a first access point (AP) a first frame indicating the amount of uplink (UL) traffic at a station (STA) associated with the second AP; and sending a second frame from the first AP to the second AP indicating: the allocation time of a transmission opportunity (TXOP) obtained by the first AP, the identifier of the second AP, the duration of uplink (UL) physical layer protocol data units (PPDUs) from the STA to the second AP during the allocation time; and the modulation and coding scheme (MCS) for the UL PPDU.

[0445] In one embodiment, there is a device arranged to perform the following operations when implemented in an access point: receiving from a second AP a first frame by a first access point (AP) a first frame indicating UL time resource information for uplink (UL) transmission from a STA to the second AP and UL frequency resource information for UL transmission; and sending from the first AP to the second AP a second frame indicating: the allocation time of a transmission opportunity (TXOP) obtained by the first AP; an identifier of the second AP; and the duration of a UL physical layer protocol data unit (PPDU) for UL transmission determined based on the UL time resource information and the UL frequency resource information.

[0446] In one embodiment, there is a device arranged to perform the following operations when implemented in an access point: sending a first frame from a first access point (AP) to a second AP, the first frame indicating uplink (UL) traffic for a station (STA) associated with the first AP; and receiving a second frame from the second AP by the first AP, the second frame indicating: the allocation time of a transmission opportunity (TXOP) obtained by the second AP, and the time period of UL-based traffic within the allocation time and used for UL transmission from the STA to the first AP.

[0447] In one embodiment, there is a device arranged to perform the following operations when implemented in an access point: sending a first frame from a first access point (AP) to a second AP, the first frame indicating uplink (UL) traffic for a station (STA) associated with the first AP; and receiving a second frame from the second AP by the first AP, the second frame indicating a time period for UL transmission from the STA to the first AP based on the UL traffic.

[0448] Various aspects of the embodiments can be implemented in a computer program product, which may be a collection of computer program instructions stored on a computer-readable storage device executable by a computer. The instructions can be any resolvable or executable code mechanism, including but not limited to scripts, interpreted programs, dynamic link libraries (DLLs), or Java classes. The instructions can be provided as a complete executable program, a partial executable program, a modification (e.g., an update) of an existing program, or an extension (e.g., a plugin) of an existing program. Furthermore, some processing of the invention can be distributed across multiple computers or processors.

[0449] Storage media suitable for storing computer program instructions include all forms of non-volatile memory, including but not limited to EPROM, EEPROM, and flash memory devices, disks such as internal and external hard drives, removable disks, and CD-ROMs. Computer program products may be distributed on such storage media or made available for download via HTTP, FTP, email, or through a server connected to a network such as the Internet.

Claims

1. A method comprising: The first access point (AP) receives a first frame from the second AP indicating the modulation and coding scheme (MCS) for downlink (DL) transmission; as well as The first AP sends a second frame to the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the first AP; as well as The time period for the DL transmission within the allocated time period, wherein the time period is determined based on the MCS.

2. A method comprising: The first access point (AP) receives a first frame from the second AP indicating DL transmission parameters for downlink (DL) transmission; as well as The first AP sends a second frame to the second AP, the second frame indicating a time period for the DL transmission, wherein the time period is determined based on the DL transmission parameters.

3. The method according to claim 2, wherein, The DL transmission parameters are selected by the second AP from a plurality of DL transmission parameters.

4. The method according to any one of claims 2-3, wherein, The DL transmission parameters are suggested by the second AP for the DL transmission.

5. The method according to any one of claims 2-4, wherein, The DL transmission parameters are preferably used by the second AP for the DL transmission.

6. The method according to any one of claims 2-5, wherein, The DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) used for the DL transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

7. The method according to any one of claims 2-6, wherein, The second frame also indicates the allocation time of the transmission opportunity (TXOP) obtained by the first AP.

8. The method according to any one of claims 2-7, wherein, The second frame also indicates the identifier of the second AP.

9. The method according to any one of claims 2-8, wherein, The DL transmission is a multi-AP transmission that includes the second AP.

10. The method according to claim 9, wherein, The multi-AP transmission is initiated by the first AP.

11. The method according to any one of claims 9 or 10, wherein, The multi-AP transmission includes the first AP.

12. The method according to any one of claims 2-11, wherein, The first frame includes a downlink (DL) buffer status report (BSR).

13. The method according to claim 12, wherein, The time period used for the DL transmission is further based on the DL BSR.

14. The method according to claim 13, wherein, The DL BSR indicates the DL traffic buffered at the second AP.

15. The method according to any one of claims 2-14, further comprising: The first AP sends a third frame to the second AP, which requests a buffer status report (BSR) for the DL transmission from the second AP.

16. A method comprising: The first access point (AP) receives the first frame of a DL buffer status report (BSR) indicating downlink (DL) transmission from the second AP; as well as The first AP sends a second frame to the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the first AP; The identifier of the second AP; The time period used for the DL transmission; as well as DL transmission parameters used by the second AP for performing the DL transmission.

17. The method according to claim 16, wherein, At least one of the time period used for the second AP to perform the DL transmission and the DL transmission parameters is determined based on the DL BSR.

18. The method according to any one of claim 16 or 17, wherein, The DL transmission is a multi-AP transmission performed during the allocation time of the TXOP.

19. The method according to claim 18, wherein, The multi-AP transmission is a coordinated orthogonal frequency division multiple access (C-OFDMA) transmission.

20. The method of claim 16, wherein, The DL transmission includes DL Physical Protocol Data Units (PPDUs).

21. The method according to claim 20, wherein, The time period of the DL transmission includes the length of the DL PPDU.

22. The method according to any one of claims 16-21, wherein, The DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) used for the DL transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

23. A method comprising: The first access point (AP) sends a first frame to the second AP indicating the modulation and coding scheme (MCS) for DL ​​transmission; as well as The first AP receives a second frame from the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the second AP; as well as The time period for the DL transmission within the allocated time period, wherein the time period is determined based on the MCS.

24. A method comprising: The first access point (AP) sends a first frame to the second AP, indicating DL transmission parameters for downlink (DL) transmission; as well as The first AP receives a second frame from the second AP indicating a time period for the DL transmission, wherein the time period is determined based on the DL transmission parameters.

25. The method according to claim 24, wherein, The DL transmission parameters are selected by the first AP from a plurality of DL transmission parameters.

26. The method according to any one of claims 24 or 25, wherein, The DL transmission parameters are suggested by the first AP for the DL transmission.

27. The method according to any one of claims 24 to 26, wherein, The DL transmission parameters are preferably used by the first AP for the DL transmission.

28. The method according to any one of claims 24 to 27, wherein, The DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) used for the DL transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

29. The method according to any one of the preceding claims, wherein, The DL transmission parameters include DL time resource allocation information or DL ​​frequency resource allocation information for the downlink (DL) transmission.

30. The method according to any one of the preceding claims, wherein, The DL time resource allocation information indicates the duration of the DL transmission.

31. The method according to any one of the preceding claims, wherein, The DL frequency resource allocation information includes the resource unit (RU) size used for the DL transmission.

32. The method according to any one of the preceding claims, wherein, The time period used for the DL transmission is determined based on the DL time resource allocation information or the DL frequency resource allocation information.

33. The method according to any one of claims 24-32, wherein, The second frame also indicates the allocation time of the transmission opportunity (TXOP) obtained by the second AP.

34. The method according to any one of the preceding claims, wherein, The second frame includes a multi-user request to send triggered TXOP sharing (MU-RTS TXS) trigger frame or a multi-AP trigger frame.

35. The method according to any one of claims 24-34, wherein, The second frame also indicates the identifier of the first AP.

36. The method according to any one of claims 24-35, wherein, The DL transmission is a multi-AP transmission that includes the first AP.

37. The method of claim 36, wherein, The multi-AP transmission is initiated by the second AP.

38. The method according to any one of claims 36 or 37, wherein, The multi-AP transmission includes the second AP.

39. The method according to any one of the preceding claims, wherein, The multi-AP transmission is a coordinated orthogonal frequency division multiple access (C-OFDMA) transmission, a coordinated time division multiple access (C-TDMA) transmission, a coordinated spatial multiplexing (C-SR) transmission, a coordinated beamforming (C-BF) transmission, or a coordinated joint transmission.

40. The method according to any one of the preceding claims, wherein, The first frame includes a downlink (DL) buffer status report (BSR).

41. The method according to any one of the preceding claims, wherein, The time period used for the DL transmission is further based on the DL BSR.

42. The method according to any one of claims 40 or 41, wherein, The DL BSR indicates the DL traffic buffered at the first AP.

43. The method according to any one of claims 24-42, further comprising: The first AP receives a third frame from the second AP, and the third frame requests a buffer status report (BSR) from the first AP.

44. The method according to any one of the preceding claims, wherein, The BSR is a Coordinated Orthogonal Frequency Division Multiple Access (C-OFDMA) BSR.

45. The method according to any one of claims 43 or 44, wherein, The third frame includes a Buffer Status Report Polling (BSRP) trigger frame, a basic trigger frame, a polling frame, or a request frame.

46. ​​The method according to any one of claims 43-45, further comprising: In response to the third frame, the first AP sends the first frame to the second AP.

47. The method according to any one of claims 24-46, wherein, The first frame includes an action frame.

48. The method according to claim 25, wherein, The action frame includes information elements containing the DL transmission parameters.

49. The method according to any one of claims 24-27, wherein, The first frame includes either a Quality of Service (QoS) empty frame or a data frame.

50. The method according to claim 49, wherein, The QoS empty frame or data frame includes an aggregation control (A-Control) field containing the DL transmission parameters.

51. The method according to any one of claims 24-50, further comprising: The first AP uses the DL transmission parameters and transmits Physical Layer Protocol Data Units (PPDUs) during the time period used for the DL transmission.

52. A method comprising: The first frame of the DL buffer status report (BSR), indicating the use of downlink (DL) transmission, is sent from the second AP by the first access point (AP). as well as The first AP receives a second frame from the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the second AP; The identifier of the first AP; The time period used for the DL transmission; as well as DL transmission parameters used by the first AP to perform the DL transmission.

53. The method according to claim 52, wherein, At least one of the time period used for the first AP to perform the DL transmission and the DL transmission parameters is determined based on the BSR.

54. The method according to any one of claims 52 or 53, wherein, The DL transmission is a multi-AP transmission performed during the allocation time of the TXOP.

55. The method according to claim 54, wherein, The multi-AP transmission is a coordinated orthogonal frequency division multiple access (C-OFDMA) transmission.

56. The method according to claim 52, wherein, The DL transmission includes DL Physical Protocol Data Units (PPDUs).

57. The method according to claim 56, wherein, The time period of the DL transmission includes the length of the DL PPDU.

58. The method according to any one of claims 52-57, wherein, The DL transmission parameters include one or more of the following: modulation and coding scheme (MCS) used for the DL transmission, bandwidth size, resource unit (RU) size, physical layer protocol data unit (PPDU) type, or number of spatial streams.

59. A computer program product that can be stored on a computer-readable medium and configured to perform the method according to any one of the preceding claims when run on a processor.

60. A device, when implemented in a first access point, is arranged as follows: Receive the first frame from the second AP to indicate the modulation and coding scheme (MCS) for downlink (DL) transmission; and A second frame is sent to the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the first AP; and The time period for the DL transmission within the allocated time, wherein, The time period is determined based on the MCS.

61. A device, when implemented in a first access point, is arranged as follows: The first access point (AP) receives a first frame from the second AP indicating DL transmission parameters for downlink (DL) transmission; and Send a second frame to the second AP indicating the time period for the DL transmission, wherein, The time period is determined based on the DL transmission parameters.

62. A device, when implemented in a first access point, is arranged as follows: Send the first frame to the second AP, indicating the modulation and coding scheme (MCS) for DL ​​transmission; and A second frame is received from the second AP, and the second frame indicates: The allocation time of the transmission opportunity (TXOP) obtained by the second AP; and The time period for the DL transmission within the allocated time, wherein, The time period is determined based on the MCS.

63. A device, when implemented at a first access point, is arranged as follows: Send a first frame to the second AP indicating DL transmission parameters for downlink (DL) transmission; and Receive a second frame from the second AP indicating the time period for the DL transmission, wherein, The time period is determined based on the DL transmission parameters.

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