Power State Transition for Dynamic Power Save Mode

Abstract

A first station (STA) transitions to a low capability mode of a power save mode. The first STA receives, from an access point (AP), a trigger frame indicating, or allocating, the first STA and a second STA. The first STA transitions from the low capability mode to a high capability mode of the power save mode. The first STA transmits, to the AP, an uplink (UL) frame soliciting an acknowledgment frame. In response to the UL frame, the STA receives, from the AP, the acknowledgment frame, wherein the acknowledgment frame indicates absence at the AP of a downlink buffered bufferable unit (BU) for the first STA and is addressed to the first STA and the second STA. Based on receiving the acknowledgment frame, the STA transitions from the high capability mode to the low capability mode.

Description

Docket No.: 24-3051 PCTTITLEPower State Transition for Dynamic Power Save Mode CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 716,793, filed November6, 2024, and U.S. Provisional Application No. 63 / 768,518, filed March 7, 2025, both which are hereby incorporated by reference in their entireties.BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

[0005] FIG. 3 illustrates an example of target wake time (TWT) operation.

[0006] FIG. 4 illustrates an example of TWT operation in an environment including an AP multi-link device (AP MLD) and a station multi-link device (STA MLD).

[0007] FIG. 5 illustrates an example TWT element which may be used to support individual TWT operation.

[0008] FIG. 6 illustrates an example TWT element which may be used to support restricted TWT (r-TWT) operation.

[0009] FIG. 7 illustrates an example of individual TWT operation.

[0010] FIG. 8 illustrates an example of broadcast TWT operation.

[0011] FIG. 9 illustrates an example of TWT protection in individual TWT operation.

[0012] FIG. 10 illustrates an example of a power save (PS) operation in a TWT service period (SP).

[0013] FIG. 11 illustrates a further example of a PS operation in a TWT SP.

[0014] FIG. 12 illustrates an example that highlights a potential problem that may arise using a dynamic power save (DPS) operation.

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

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

[0017] FIG. 15 illustrates an example operation according to an embodiment.

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

[0019] FIG. 17 illustrates an example operation according to an embodiment.

[0020] FIG. 18 illustrates an example operation according to an embodiment.

[0021] FIG. 19 illustrates an example operation according to an embodiment.

[0022] FIG. 20 illustrates an example operation according to an embodiment.

[0023] FIG. 21 illustrates an example operation according to an embodiment.Docket No.: 24-3051 PCT

[0024] FIG. 22 illustrates an example operation according to an embodiment.

[0025] FIG. 23 illustrates an example operation according to an embodiment.

[0026] FIG. 24 illustrates an example operation according to an embodiment.

[0027] FIG. 25 illustrates an example operation according to an embodiment.

[0028] FIG. 26 illustrates an example operation according to an embodiment.

[0029] FIG. 27 illustrates an example operation according to an embodiment.

[0030] FIG. 28 illustrates an example operation according to an embodiment.

[0031] FIG. 29 illustrates an example operation according to an embodiment.

[0032] FIG. 30 illustrates an example process according to an embodiment.

[0033] FIG. 31 illustrates an example process according to an embodiment.

[0034] FIG. 32 illustrates an example process according to an embodiment.

[0035] FIG. 33 illustrates an example process according to an embodiment.

[0036] FIG. 34 illustrates an example process according to an embodiment.DETAILED DESCRIPTION

[0037] In the present disclosure, various embodiments are presented as examples of how the disclosed techniques may be implemented and / or how the disclosed techniques may be practiced in environments and scenarios. It will be apparent to persons skilled in the relevant art that various changes in form and detail can be made therein without departing from the scope. After reading the description, it will be apparent to one skilled in the relevant art how to implement alternative embodiments. The present embodiments may not be limited by any of the described exemplary embodiments. The embodiments of the present disclosure will be described with reference to the accompanying drawings. Limitations, features, and / or elements from the disclosed example embodiments may be combined to create further embodiments within the scope of the disclosure. Any figures which highlight the functionality and advantages, are presented for example purposes only. The disclosed architecture is sufficiently flexible and configurable, such that it may be utilized in ways other than that shown. For example, the actions listed in any flowchart may be re-ordered or only optionally used in some embodiments.

[0038] Embodiments may be configured to operate as needed. The disclosed mechanism may be performed when certain criteria are met, for example, in a station, an access point, a radio environment, a network, a combination of the above, and / or the like. Example criteria may be based, at least in part, on for example, wireless device or network node configurations, traffic load, initial system set up, packet sizes, traffic characteristics, a combination of the above, and / or the like. When the one or more criteria are met, various example embodiments may be applied. Therefore, it may be possible to implement example embodiments that selectively implement disclosed protocols.

[0039] In this disclosure, "a” and “an" and similar phrases are to be interpreted as “at least one” and “one or more.” Similarly, any term that ends with the suffix “(s)” is to be interpreted as “at least one” and “one orDocket No.: 24-3051 PCT more.” In this disclosure, the term "may” is to be interpreted as “may, for example.” In other words, the term “may” is indicative that the phrase following the term “may” is an example of one of a multitude of suitable possibilities that may, or may not, be employed by one or more of the various embodiments. The terms “comprises” and “consists of', as used herein, enumerate one or more components of the element being described. The term “comprises” is interchangeable with “includes” and does not exclude unenumerated components from being included in the element being described. By contrast, “consists of’ provides a complete enumeration of the one or more components of the element being described. The term “based on”, as used herein, may be interpreted as “based at least in part on” rather than, for example, “based solely on”. The term “and / or” as used herein represents any possible combination of enumerated elements. For example, “A, B, and / or C” may represent A; B; C; A and B; A and C; B and C; or A, B, and C.

[0040] If A and B are sets and every element of A is an element of B, A is called a subset of B. In this specification, only non-empty sets and subsets are considered. For example, possible subsets of B = {STA1 , STA2] are: {STA1}, {STA2}, and {STA1 , STA2}. The phrase “based on” (or equally “based at least on”) is indicative that the phrase following the term “based on” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “in response to” (or equally “in response at least to”) is indicative that the phrase following the phrase “in response to” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “depending on” (or equally “depending at least to") is indicative that the phrase following the phrase “depending on" is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments. The phrase “employing / using” (or equally “employing / using at least”) is indicative that the phrase following the phrase “employing / using” is an example of one of a multitude of suitable possibilities that may, or may not, be employed to one or more of the various embodiments.

[0041] The term configured may relate to the capacity of a device whether the device is in an operational or non-operational state. Configured may refer to specific settings in a device that effect the operational characteristics of the device whether the device is in an operational or non-operational state. In other words, the hardware, software, firmware, registers, memory values, and / or the like may be “configured” within a device, whether the device is in an operational or nonoperational state, to provide the device with specific characteristics. Terms such as “a control message to cause in a device” may mean that a control message has parameters that may be used to configure specific characteristics or may be used to implement certain actions in the device, whether the device is in an operational or non-operational state.

[0042] In this disclosure, parameters (or equally called, fields, or Information elements: lEs) may comprise one or more information objects, and an information object may comprise one or more other objects. For example, if parameter (IE) N comprises parameter (IE) M, and parameter (IE) M comprises parameter (IE) K, and parameter (IE) K comprises parameter (information element) J. Then, for example, N comprises K,Docket No.: 24-3051 PCT and N comprises J. In an example embodiment, when one or more messages / frames comprise a plurality of parameters, it implies that a parameter in the plurality of parameters is in at least one of the one or more messages / frames but does not have to be in each of the one or more messages / frames.

[0043] Many features presented are described as being optional through the use of “may” or the use of parentheses. For the sake of brevity and legibility, the present disclosure does not explicitly recite each and every permutation that may be obtained by choosing from the set of optional features. The present disclosure is to be interpreted as explicitly disclosing all such permutations. For example, a system described as having three optional features may be embodied in seven ways, namely with just one of the three possible features, with any two of the three possible features or with three of the three possible features.

[0044] Many of the elements described in the disclosed embodiments may be implemented as modules. A module is defined here as an element that performs a defined function and has a defined interface to other elements. The modules described in this disclosure may be implemented in hardware, software in combination with hardware, firmware, wetware (e.g. hardware with a biological element) or a combination thereof, which may be behaviorally equivalent. For example, modules may be implemented as a software routine written in a computer language configured to be executed by a hardware machine (such as C, C++, Fortran, Java, Basic, Matlab or the like) or a modeling / simulation program such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript. It may be possible to implement modules using physical hardware that incorporates discrete or programmable analog, digital and / or quantum hardware. Examples of programmable hardware comprise: computers, microcontrollers, microprocessors, application-specific integrated circuits (ASICs); field programmable gate arrays (FPGAs); and complex programmable logic devices (CPLDs). Computers, microcontrollers and microprocessors are programmed using languages such as assembly, C, C++ or the like. FPGAs, ASICs and CPLDs are often programmed using hardware description languages (HDL) such as VHSIC hardware description language (VHDL) or Verilog that configure connections between internal hardware modules with lesser functionality on a programmable device. The mentioned technologies are often used in combination to achieve the result of a functional module.

[0045] FIG. 1 illustrates example wireless communication networks in which embodiments of the present disclosure may be implemented.

[0046] As shown in FIG. 1 , the example wireless communication networks may include an Institute of Electrical and Electronic Engineers (IEEE) 802.11 (WLAN) infra-structure network 102. WLAN infra-structure network 102 may include one or more basic service sets (BSSs) 1 10 and 120 and a distribution system (DS) 130.

[0047] BSS 110-1 and 110-2 each includes a set of an access point (AP or AP STA) and at least one station (STA or non-AP STA). For example, BSS 110-1 includes an AP 104-1 and a STA 106-1 , and BSS 1 10-2 includes an AP 104-2 and STAs 106-2 and 106-3. The AP and the at least one STA in a BSS perform an association procedure to communicate with each other.Docket No.: 24-3051 PCT

[0048] DS 130 may be configured to connect BSS 110-1 and BSS 110-2. As such, DS 130 may enable an extended service set (ESS) 150. Within ESS 150, APs 104-1 and 104-2 are connected via DS 130 and may have the same service set identification (SSID).

[0049] WLAN infra-structure network 102 may be coupled to one or more external networks. For example, as shown in FIG. 1 , WLAN infra-structure network 102 may be connected to another network 108 (e.g., 802.X) via a portal 140. Portal 140 may function as a bridge connecting DS 130 of WLAN infra-structure network 102 with the other network 108.

[0050] The example wireless communication networks illustrated in FIG. 1 may further include one or more ad-hoc networks or independent BSSs (IBSSs). An ad-hoc network or IBSS is a network that includes a plurality of STAs that are within communication range of each other. The plurality of STAs are configured so that they may communicate with each other using direct peer-to-peer communication (i.e., not via an AP).

[0051] For example, in FIG. 1 , STAs 106-4, 106-5, and 106-6 may be configured to form a first IBSS 112- 1 . Similarly, STAs 106-7 and 106-8 may be configured to form a second IBSS 112-2. Since an IBSS does not include an AP, it does not include a centralized management entity. Rather, STAs within an IBSS are managed in a distributed manner. STAs forming an IBSS may be fixed or mobile.

[0052] A STA as a predetermined functional medium may include a medium access control (MAC) layer that complies with an IEEE 802.11 standard. A physical layer interface for a radio medium may be used among the APs and the non-AP stations (STAs). The STA may also be referred to using various other terms, including mobile terminal, wireless device, wireless transmit / receive unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, or user. For example, the term “user" may be used to denote a STA participating in uplink Multi-user Multiple Input, Multiple Output (MU MIMO) and / or uplink Orthogonal Frequency Division Multiple Access (OFDMA) transmission.

[0053] A physical layer (PHY) protocol data unit (PPDU) may be a composite structure that includes a PHY preamble and a payload in the form of a PHY service data unit (PSDU). For example, the PSDU may include a PHY preamble and header and / or one or more MAC protocol data units (MPDUs). The information provided in the PHY preamble may be used by a receiving device to decode the subsequent data in the PSDU. In instances in which PPDUs are transmitted over a bonded channel (channel formed through channel bonding), the preamble fields may be duplicated and transmitted in each of the multiple component channels. The PHY preamble may include both a legacy portion (or “legacy preamble”) and a non-legacy portion (or “non-legacy preamble”). The legacy preamble may be used for packet detection, automatic gain control and channel estimation, among other uses. The legacy preamble also may generally be used to maintain compatibility with legacy devices. The format of, coding of, and information provided in the non-legacy portion of the preamble is based on the particular IEEE 802.11 protocol to be used to transmit the payload.

[0054] A frequency band may include one or more sub-bands or frequency channels. For example, PPDUs conforming to the IEEE 802.11 n, 802.1 1ac, 802.11 ax and / or 802.11 be standard amendments may beDocket No.: 24-3051 PCT transmitted over the 2.4 GHz, 5 GHz, and / or 6 GHz bands, each of which may be divided into multiple 20 MHz channels. The PPDUs may be transmitted over a physical channel having a minimum bandwidth of 20 MHz. Larger channels may be formed through channel bonding. For example, PPDUs may be transmitted over physical channels having bandwidths of 40 MHz, 80 MHz, 160 MHz, or 320 MHz by bonding together multiple 20 MHz channels.

[0055] FIG. 2 is a block diagram illustrating example implementations of a STA 210 and an AP 260. As shown in FIG. 2, STA 210 may include at least one processor 220, a memory 230, and at least one transceiver 240. AP 260 may include at least one processor 270, a memory 280, and at least one transceiver 290. Processor 220 / 270 may be operatively connected to memory 230 / 280 and / or to transceiver 240 / 290.

[0056] Processor 220 / 270 may implement functions of the PHY layer, the MAC layer, and / or the logical link control (LLC) layer of the corresponding device (STA 210 or AP 260). Processor 220 / 270 may include one or more processors and / or one or more controllers. The one or more processors and / or one or more controllers may comprise, for example, a general-purpose processor, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a logic circuit, or a chipset, for example.

[0057] Memory 230 / 280 may include a read-only memory (ROM), a random-access memory (RAM), a flash memory, a memory card, a storage medium, and / or other storage unit. Memory 230 / 280 may comprise one or more non-transitory computer readable mediums. Memory 230 / 280 may store computer program instructions or code that may be executed by processor 220 / 270 to carry out one or more of the operations / embodiments discussed in the present application. Memory 230 / 280 may be implemented (or positioned) within processor 220 / 270 or external to processor 220 / 270. Memory 230 / 280 may be operatively connected to processor 220 / 270 via various means known in the art.

[0058] Transceiver 240 / 290 may be configured to transmit / receive radio signals. In an embodiment, transceiver 240 / 290 may implement a PHY layer of the corresponding device (STA 210 or AP 260). In an embodiment, STA 210 and / or AP 260 may be a multi-link device (MLD), that is a device capable of operating over multiple links as defined by the IEEE 802.11 standard. As such, STA 210 and / or AP 260 may each implement multiple PHY layers. The multiple PHY layers may be implemented using one or more of transceivers 240 / 290.

[0059] Target wake time (TWT), a feature introduced in the IEEE 802.11 ah standard, allows STAs to manage activity in the BSS by scheduling STAs to operate at different times to reduce contention. TWTs may allow STAs to reduce the required amount of time that a STA utilizing a power management mode may be awake. TWTs may be individual TWTs or broadcast TWTs. Individual TWTs follow a negotiated TWT agreement between STAs. Broadcast TWTs are based on a schedule set and provided to STAs by an AP.

[0060] In an individual TWT, a STA that requests a TWT agreement is called a TWT requesting STA. The TWT requesting STA may be a non-AP STA for example. The STA that responds to the request is called aDocket No.: 24-3051 PCTTWT responding STA. The TWT responding STA may be an AP for example. The TWT requesting STA is assigned specific times to wake up and exchange frames with the TWT responding STA. The TWT requesting STA may communicate wake scheduling information to the TWT responding STA. The TWT responding STA may transmit TWT values to the TWT requesting STA when a TWT agreement is established between them.

[0061] When explicit TWT is employed, the TWT requesting STA may wake up and perform a frame exchange. The TWT requesting STA may receive a next TWT information in a response from the TWT responding STA. When implicit TWT is used, the TWT requesting STA may calculate a next TWT by adding a fixed value to the current TWT value.

[0062] The TWT values for implicit TWT may be periodic. The TWT requesting STA operating with an implicit TWT agreement may determine a next TWT service period (TWT SP) start time by adding a value of a TWT wake interval associated with the TWT agreement to the value of the start time of the current TWT SP. The TWT responding STA may include the start time for a series of TWT SPs corresponding to a single TWT flow identifier of an implicit TWT agreement in a target wake time field of a TWT element. The TWT element may contain a value of ‘accept TWT’ in a TWT setup command field. The start time of the TWT SP series may indicate the start time of a first TWT SP in the series. Start times of subsequent TWT SPs may be determined by adding the value of the TWT wake interval to the start time of the current TWT SP. In an example, the TWT requesting STA, awake for an implicit TWT SP, may enter a doze state after the TWT SP has elapsed or after receiving an end of service period (EOSP) field equal to 1 from the TWT responding STA, whichever occurs first.

[0063] A TWT session may be negotiated between an AP and a STA. The TWT session may configure a TWT SP of DL and UL traffic between the AP and the STA. Expected traffic may be limited within the negotiated SP. The TWT SP may start at a specific time. The TWT SP may run for a SP duration. The TWT SP may repeat every SP interval.

[0064] FIG. 3 illustrates an example 300 of TWT operation. As shown in FIG. 3, example 300 includes an AP 311 , a STA 312, and a STA 313. AP 31 1 and STA 312 may establish a TWT SP 320. AP 311 and STA 313 may establish a TWT SP 321 . TWT SP 320 and TWT SP 321 may repeat as shown in FIG. 3, such that TWT SP 320 may include a first TWT SP 320-1 and a second TWT SP 320-2, and such that TWT SP 321 may include a first TWT SP 321 -1 and a second TWT SP 321 -2.

[0065] AP 311 and STA 312 may exchange frames during first TWT SP 320-1. STA 312 may enter a doze state at the end of TWT SP 320-1 and may remain in the doze state until the start of second TWT SP 320-2. The start of second TWT SP 320-2 may be indicated by a TWT wake interval 330 associated with TWT SP 320. AP 311 and STA 312 may again exchange frames during second TWT SP 320-2.

[0066] Similarly, AP 311 and STA 313 may exchange frames during first TWT SP 321-1. STA 313 may enter a doze state at the end of first TWT SP 321 -1 and may remain in the doze state until the start of secondDocket No.: 24-3051 PCTTWT SP 321-2. The start of second TWT SP 321-2 may be indicated by a TWT wake interval 331 associated with TWT SP 321 . AP 311 and STA 313 may again exchange frames during second TWT SP 31-2.

[0067] In an awake state, a STA may be fully powered. The STA may transmit and / or receive a frame to / from an AP or another STA. In a doze state, a STA may not transmit and may not receive a frame to / from an AP or another STA.

[0068] An MLD is an entity capable of managing communication over multiple links. The MLD may be a logical entity and may have more than one affiliated station (STA). The MLD may have a single MAC service access point (MAC-SAP) to the LLC layer, which includes a MAC data service. An MLD may be an access point MLD (AP MLD) when a STA affiliated with the MLD is an AP STA (or an AP). An MLD may be a non- access point MLD (non-AP MLD) or STA MLD when a STA affiliated with the MLD is a non-AP STA (or a STA).

[0069] During negotiation of TWT agreements, a TWT requesting STA affiliated with a STA MLD and a TWT responding STA affiliated with an AP MLD may communicate multiple TWT elements. The TWT elements may comprise link ID bitmap subfields indicating different link(s) in a TWT setup frame. The TWT parameters provided by a TWT element may be applied to the respective link that is indicated in the TWT element.

[0070] FIG. 4 illustrates an example 400 of TWT operation in a multi-link environment including an AP multilink device (AP MLD) 410 and a STA multi-link device (STA MLD) 420. As shown in FIG. 4, AP MLD 410 may have three affiliated APs, AP 411 , AP2 412, and AP3 413. In an example, AP 411 , AP2 412, and AP3 413 may operate respectively on the 2.4 GHz band, the 5 GHz band, and the 6 GHz band. STA MLD 420 may have three affiliated STAs, STA 421 , STA 422, and STA 423. In an example, STA 421 , STA 422, and STA 423 may operate respectively on the 2 4 GHz band, the 5 GHz band, and the 6 GHz band. In an example, AP 411 , AP2 412, and AP3 413 may be communicatively coupled via a first link (link 1), a second link (link 2), and a third link (link 3) respectively with STA 421 , STA 422, and STA 423, respectively.

[0071] In an example, STA 421 may transmit a TWT request to AP 41 1. The TWT request may include three TWT elements. Each TWT element may indicate a respective link of links 1-3 and may request the setup of a TWT agreement for the indicated link. The three TWT elements may have different TWT parameters, such as target wake time (TWT). In response to the TWT request, AP 411 may transmit a TWT response to STA 421 . The TWT response may include three TWT elements. Each TWT element may indicate a respective link of links 1-3 and may include a value of ‘accept TWT in a TWT setup command field.

[0072] Successful TWT agreement setup on links 1-3 establishes three TWT SPs with same or different TWT parameters on links 1 -3 respectively. The target wake time field of the TWT element indicating a given link indicates the start time of the TWP SP for that link. The starting time may be indicated in reference to a time synchronization function (TSF) time of the link.

[0073] In example 400, initial TWT SPs 430-1 , 430-2, and 430-3 of links 1-3 respectively may be aligned. TWT wake intervals associated with the TWT agreements of links 1-3 respectively may be set differently. AsDocket No.: 24-3051 PCT such, second TWT SPs 431-1 , 431 -2, and 431 -3 of links 1-3 respectively may not be aligned. STA 421 , STA 422, and STA 423 may enter a doze state between the end of initial TWT SPs 430-1 , 430-2, and 430-3, respectively, and the start of second TWT SPs 431-1 , 431-2, 431-3, respectively.

[0074] FIG. 5 illustrates an example target wake time (TWT) element 500 which may be used to support individual TWT operation.

[0075] In an example, an AP and a STA may use TWT element 500 to negotiate a TWT agreement. The AP and / or the STA may transmit TWT element 500 in an individually addressed management frame. The management frame may be of the type action, action no ack, (re)association request / response, and probe request response, for example.

[0076] The TWT schedule and parameters may be provided during a TWT setup phase. Renegotiation / changes of TWT schedules may be signaled via individually addressed frames that contain the updated TWT schedule / parameters. The frames may be management frames as described above or control or data frames that carry a field containing the updated TWT schedule / parameters.

[0077] Referring to FIG. 5, TWT element 500 includes an element ID field, a length field, a control field, and a TWT parameter information field.

[0078] The element ID field (e.g., 1 octet in length) may indicate that information element 500 is a TWT element. The length field (e.g., 1 octet) may indicate the length of TWT element 500 starting from the control field until an end of TWT element 500. The end of TWT element 500 may be the end of a TWT Channel field or the end of a Link ID bitmap field of the TWT parameter information field.

[0079] The TWT parameter information field may include a request type field (e.g., 2 octets), a target wake time field (e.g., 8 octets or less), a TWT group assignment field (e.g., 9, 3, 2, or 0 octets), a nominal minimal TWT wake duration field (e.g., 1 octet), a TWT wake interval mantissa (e.g., 2 octets), a TWT channel field (e.g., 1 octet), an optional NDP paging field (e.g., 0 or 4 octets), and / or a Link ID bitmaps field (e.g., 0 or 2 Octets ).

[0080] The request type field may indicate a type of TWT request. The request type field may include a TWT request field (e.g., 1 bit), a TWT setup command field (e.g., 3 bits), a trigger field (e.g., 1 bit), an implicit field (e.g., 1 bit), a flow type (e.g., 1 bit), a TWT flow identifier (e.g., 3 bits), a TWT wake interval exponent (e.g., 5 bits), and / or a TWT protection field (e.g., 1 bit).

[0081] The TWT request field may indicate whether the TWT element 500 represents a request. If TWT request field has a value of 1 , then the TWT element 500 may represent a request to initiate TWT scheduling / setup.

[0082] The TWT setup command field may indicate a type of TWT command. In a TWT request, the type of TWT command indicated may be: a request TWT (the TWT responding STA specifies the TWT value; e.g., field set to 0), a suggest TWT (the TWT requesting STA suggests a TWT value; e.g., field set to 1), and a demand TWT (the TWT requesting STA demands a TWT value; e.g., field set to 2).Docket No.: 24-3051 PCT

[0083] In a TWT response, the type of TWT command indicated may be: TWT grouping (the TWT responding STA suggests TWT group parameters that are different than the suggested or demanded TWT parameters of the TWT requesting STA; e.g., field set to 3), accept TWT (the TWT responding STA accepts the TWT request with the TWT parameters indicated by the TWT requesting STA; e.g. field set to 4), alternate TWT (the TWT responding STA suggests TWT parameters that are different than the parameters suggested or demanded by the TWT requesting STA; e.g., field set to 5), dictate TWT (the TWT responding STA demands TWT parameters that are different than the parameters suggested or demanded by the TWT requesting STA; e.g., field set to 6), or reject TWT (the TWT responding STA rejects the TWT setup; e.g. field set to 7).

[0084] In a TWT response, the TWT command may also indicate an unsolicited response or a broadcast TWT. An unsolicited TWT response is an individually addressed frame that is intended for a specific STA. An unsolicited TWT response may be followed by an ACK frame from the STA receiving the unsolicited TWT response. A broadcast TWT may be intended for multiple STAs and may be carried in a broadcast frame such as, for example, a beacon frame. A broadcast TWT may not be acknowledged by receiving STAs.

[0085] An unsolicited TWT response may be used a TWT responding STA to demand that a recipient follow a TWT schedule contained in the TWT element. In an embodiment, an unsolicited TWT response may have the TWT request field set to 0 and a value of 'dictate TWT’ in the TWT setup command field. A broadcast TWT response may be used by a TWT responding STA to schedule a TWT for any STA that receives and decodes the TWT element.

[0086] In certain embodiments, a TWT element, such as TWT element 500, may contain TWT parameter sets for multiple TWT negotiations or indications as described herein. As such, the TWT element may include multiple instances of the Control and the TWT parameter information fields. The TWT flow identifier of the request type field indicates the TWT negotiation which parameters are carried by the TWT parameter information field.

[0087] FIG. 6 illustrates an example target wake time (TWT) element 600 which may be used to support restricted TWT (r-TWT) operation. For r-TWT, TWT element 600 may be transmitted in a broadcast management frame, which can be a beacon frame, a TIM broadcast frame, a probe response frame, etc. In this embodiment, TWT element 600 provides non-negotiated TWT schedules (e.g., broadcast TWT schedules).

[0088] As shown, TWT element 600 includes an element ID field, a length field, a control field, and a TWT parameter information field.

[0089] The element ID field (e.g., 1 octet in length) may indicate that information element 600 is a TWT element. The length field (e.g., 1 octet) may indicate the length of TWT element 600 starting from the control field until an end of TWT element 600. The end of TWT element 600 may be the end of a broadcast TWT info field or the end of a r-TWT traffic info field of the TWT parameter information field.Docket No.: 24-3051 PCT

[0090] The TWT parameter information field may include a request type field, a target wake time field (e.g2 octets), a nominal minimal TWT wake duration field (e.g., 1 octet), a TWT wake interval mantissa (e.g., 2 octets), a broadcast TWT info field (e.g., 2 octets), and an optional r-TWT traffic info field (e.g., 0 or 3 octets).

[0091] The request type field may include, among other fields, a TWT request field, a flow type field, and a TWT wake interval exponent field.

[0092] The TWT request field indicates whether TWT element 600 is a request. If the TWT request field has a value of 0, then TWT element 600 may represent a response to a request to initiate TWT scheduling / setup (solicit TWT), an unsolicited TWT response, and / or a broadcast TWT message.

[0093] The TWT wake interval represents the average time that a TWT requesting STA or a TWT scheduled STA expects to elapse between successive TWT SP start times of a TWT schedule. The TWT wake interval exponent field indicates a (base 2) exponent used to calculate the TWT wake interval in microseconds. In an embodiment, the TWT wake interval is equal to: (TWT wake interval mantissa) x 2(™T Wake lnterval ExP°nent). The TWT wake interval mantissa value is indicated in microseconds, base 2 in a TWT wake interval mantissa field of the TWT parameter information field.

[0094] The nominal minimum TWT wake duration field may indicate the minimum amount of time (in the unit indicated by a wake duration unit subfield of the control field) that a TWT requesting STA or a TWT scheduled STA is expected to be awake to complete frame exchanges for the period of the TWT wake interval.

[0095] The flow type field, in a TWT response that successfully set up a TWT agreement between a TWT requesting STA and a TWT responding STA, may indicate a type of interaction between the TWT requesting STA and the TWT responding STA within a TWT SP of the TWT agreement. A flow type field equal to 0 may indicate an announced TWT. In an announced TWT, the TWT responding STA may not transmit a frame to the TWT requesting STA within a TWT SP until the TWT responding STA receives a PS-Poll frame or a QoS Null frame from the TWT requesting STA. A flow type field equal to 1 may indicate an unannounced TWT. In an unannounced TWT, the TWT responding STA may transmit a frame to the TWT requesting STA within a TWT SP before it has received a frame from the TWT requesting STA.

[0096] Within a TWT element that includes a TWT setup command value of ‘request TWT', ‘suggest TWT’, or 'demand TWT, a broadcast TWT ID may indicate a specific broadcast TWT in which the TWT requesting STA is requesting to participate. Within a TWT element that includes a TWT setup command value of ‘accept TWT', ‘alternate TWT', 'dictate TWT', or ‘reject TWT, a broadcast TWT ID may indicate a specific broadcast TWT for which the TWT responding STA is providing TWT parameters. The value 0 in the broadcast TWT ID subfield may indicate the broadcast TWT whose membership corresponds to all STAs that are members of the BSS corresponding to the BSSID of the management frame carrying the TWT element and that is permitted to contain trigger frames with random access resource units for unassociated STAs. The Broadcast TWT ID subfield in a r-TWT Parameter set field is always set to a nonzero value.Docket No.: 24-3051 PCT

[0097] A broadcast TWT element 600 that contains a r-TWT parameter set is also referred to as a r-TWT element. A r-TWT traffic info present subfield of the broadcast TWT info field may be set to 1 to indicate the presence of the r-TWT traffic info field in TWT element 600. The r-TWT traffic info field is present in a r-TWT parameter set field when the r-TWT traffic info present subfield is set to 1 .

[0098] The r-TWT traffic info field may include a traffic info control field, a r-TWT DL TID bitmap field, and a r-TWT UL TID bitmap field.

[0099] The traffic info control field may include a DL TID bitmap valid subfield and an UL TID bitmap valid subfield. The DL TID bitmap valid subfield indicates if the r-TWT DL TID bitmap field has valid information. When the value of the DL TID bitmap valid subfield is set to 0, it may indicate that DL traffic of TIDs is identified as latency sensitive traffic, and the r-TWT DL TID bitmap field is reserved. The UL TID bitmap valid subfield may indicate if the r-TWT UL TID bitmap field has valid information. When the value of the UL TID bitmap valid subfield is set to 0, it may indicate that UL traffic of TIDs is identified as latency sensitive traffic, and the r-TWT UL TID bitmap field is reserved.

[0100] The r-TWT DL TID bitmap subfield and the r-TWT UL TID bitmap subfield may specify which TID(s) are identified by the TWT scheduling AP or the TWT scheduled STA as latency sensitive traffic streams in a downlink and a uplink direction, respectively. A value of 1 at bit position k in the bitmap indicates that TID k is classified as a latency sensitive traffic stream. A value of 0 at bit position k in the bitmap indicates that TID k is not classified as a latency sensitive traffic stream.

[0101] An individual target wake time (TWT) may be a specific time or set of times negotiated between two individual stations (e.g., a STA and another STA, or a STA and an AP, etc.) at which the stations may be awake to exchange frames during a service period (SP) of the TWT.

[0102] In trigger-enabled TWT, an AP may transmit a trigger frame for scheduling uplink multi-user transmissions from one or more ST As using uplink OFDMA (orthogonal frequency division multiple access) and / or uplink MU-MIMO (multi-user multiple input multiple output) during a trigger-enabled TWT SP. A TWT STA that receives the trigger frame from the AP may transmit a frame to the AP through a resource indicated in the trigger frame during the trigger-enabled TWT SP.

[0103] In non-trigger-enabled TWT, an AP may not be required to transmit a trigger frame to schedule uplink multi-user transmissions from one or more STAs during a non-trigger-enabled TWT SP.

[0104] In announced TWT, a STA may transmit a frame (e.g., a PS-Poll frame or a QoS null frame) to the AP to retrieve a downlink buffered data from the AP during a TWT SP. In unannounced TWT, an AP may transmit downlink data to a TWT STA without receiving a frame (e.g., a PS-Poll frame, or a QoS null frame) from the TWT STA during a TWT SP.

[0105] FIG. 7 illustrates an example 700 of individual TWT operation. As shown in FIG. 7, example 700 includes an AP 710, a STA 711 , and a STA 712. In an example, AP 710 may be a TWT responding STA and STA 711 and STA 712 may be TWT requesting STAs.Docket No.: 24-3051 PCT

[0106] In an example, STA 711 may transmit a TWT request to AP 710 to setup a first trigger-enabled TWT agreement. STA 711 may set a trigger field of the TWT request to 1 to indicate that it is requesting a trigger- enabled TWT. AP 710 may accept the first TWT agreement with STA 711 . AP 710 may confirm the acceptance in a TWT response sent to STA 711. The TWT response may indicate a next TWT 730, which indicates the time until a next TWT SP 720 according to the first TWT agreement.

[0107] In an example, AP 710 may transmit an unsolicited TWT response to STA 712 to set up a second trigger-enabled TWT agreement with STA 712 without receiving a TWT request from STA 712. The first and second TWT agreements may be set up as announced TWTs.

[0108] After the setup of the TWT agreements, STA 711 and STA 712 may enter a doze state until the start of TWT SP 720. During trigger-enabled TWT SP 720, AP 710 may transmit a trigger frame. STA 71 1 and STA 12 may respond to the trigger frame by indicating that they are in awake state. In an example, STA 71 1 may transmit a power save poll (PS-Poll) frame. The PS-Poll frame may comprise a BSSID (receiver address: RA) field set to an address of AP 710 and a transmitter address (TA) field set to an address of STA 711 . In an example, STA 712 may transmit a QoS null frame in response to the trigger frame. The QoS null frame may comprise a MAC header (e.g. , a frame control field, a duration field, address fields, a sequence control field, QoS control field) without a frame body.

[0109] In response to the PS-Poll frame and the QoS null frame, AP 710 may transmit a multi-STA Block Ack (M-BA) frame. The M-BA frame may include acknowledgement information associated with the PS-Poll frame and the QoS null frame received from STAs 711 and 712 respectively. Subsequently, STA 711 and STA 712 may receive downlink bufferable units (DL BUs) from AP 710. The DL BUs may include a medium access control (MAC) service data unit (MSDU), an aggregate MAC service data unit (A-MSDU), and / or a bufferable MAC management protocol data unit (MMPDU). STA 711 and STA 712 may transmit Block Ack (BA) frames in response to the DL BUs. At the end of the TWT SP 720, STA 71 1 and STA 712 may return to a doze state.

[0110] A STA may execute individual TWT setup exchanges. The STA may not transmit frames to an AP outside of negotiated TWT SPs. The STA may not transmit frames that are not contained within high efficiency trigger-based physical protocol data units (HE TB PPDUs) to the AP within trigger-enabled TWT SPs. A HE TB PPDU may be transmitted by a STA based on receiving a trigger frame triggering uplink multiuser transmissions.

[0111] The AP of a trigger-enabled TWT agreement may schedule for transmission a trigger frame for a STA within the trigger-enabled TWT SP. The STA may transmit an HE TB PPDU as a response to the trigger frame sent during the trigger-enabled TWT SP. A STA that is in power save (PS) mode may include a PS- Poll frame or a QoS null frame in the HE TB PPDU if the TWT is an announced TWT, to indicate to the AP that the STA is currently in the awake state. The AP that receives the PS-Poll frame or the QoS Null frameDocket No.: 24-3051 PCT or any other indication from an STA in PS mode, may deliver to the STA as many buffered BUs as are available at the AP during the TWT SP.

[0112] A broadcast target wake time (TWT) may be a specific time or set of times broadcast by an AP to one or more STAs at which the STAs may be awake to exchange frames with the AP during a SP of the TWT.

[0113] FIG. 8 illustrates an example 800 of broadcast TWT operation. As shown in FIG. 8, example 800 includes an AP 810, a STA 81 1 , and a STA 812. In an example 800, AP 810 may be a TWT scheduling AP and STA 81 1 and STA 812 may be TWT scheduled STAs.

[0114] In an example, AP 810 may include a broadcast TWT element in a beacon frame that indicates a broadcast TWT SP 820. During the broadcast TWT SP 820, AP 810 may transmit trigger frames or DL BUs to STA 81 1 and STA 812. Beacon frames may be sent by AP 810 periodically at target beacon transmission times (TBTTs). The number of time units (TUs) between consecutive TBTTs is called the beacon interval. A TU is equal to 1024 microseconds.

[0115] In an example, STA 811 and STA 812 may enter a doze state until the first target beacon transmission time (TBTT). STA 811 and STA 812 may wake up to receive the beacon frame at the first TBTT to determine the broadcast TWT. Upon reception of a broadcast TWT element in a beacon frame, STA 81 1 and STA 812 may re-enter the doze state until the start of trigger-enabled TWT SP 820.

[0116] During trigger-enabled TWT SP 820, AP 810 may transmit a basic trigger frame to STA 81 1 and STA 812. STA 811 may indicate that it is awake by transmitting a PS-Poll, and STA 812 may indicate that it is awake by transmitting a QoS null frame in response to the basic trigger frame. Subsequently, STA 81 1 and STA 812 may receive DL BUs from AP 810. STA 81 1 and STA 812 may return to the doze state outside of the TWT SP 720.

[0117] In an example, a STA that intends to operate in power save mode may negotiate a wake TBTT and a wake interval with the AP. For example, as shown in FIG. 8, STA 811 may transmit a TWT request to AP 810 that identifies a wake TBTT of the first beacon frame and a wake interval between subsequent beacon frames. AP 810 may respond with a TWT response to the TWT request confirming the wake TBTT and wake interval. After successfully completing the negotiation, STA 81 1 may enter a doze state until a first negotiated wake TBTT 830. STA 811 may be in an awake state to listen to the beacon frame transmitted at first negotiated wake TBTT 830. If STA 81 1 receives a beacon frame from AP 810 at or after TBTT 830, STA 81 1 may return to the doze state until the next wake TBTT unless a traffic indication map (TIM) element in a beacon frame includes a positive indication for STA 811 . The STA 81 1 may return to the doze state after a nominal minimum TBTT wake duration time has elapsed from the TBTT start time.

[0118] A Network Allocation Vector (NAV) is an indicator, maintained by a station (STA), of time periods when transmission onto the wireless medium (WM) may not be initiated by the STA regardless of whether the clear channel assessment (CCA) function of the STA senses that the WM is busy. A STA that receivesDocket No.: 24-3051 PCT at least one valid frame in a PSDU may update its NAV with the information from any valid duration field in the PSDU. The STA may update the NAV when a value of the received duration field is greater than the current NAV value of the STA.

[0119] A TWT protection is a mechanism employed to protect a TWT session from external STA transmissions. During a TWT SP configured to protect the TWT session, a STA that initiates a transmission opportunity (TXOP) to transmit a frame may transmit a request to transmit (RTS) frame or a clear to transmit (CTS) frame to protect the TWT session by setting the NAV of other STAs based on receiving of the RTS frame and / or the CTS frame. The RTS frame may comprise a frame control field, a duration field, a receiver address (RA) field, a transmitter address (TA) field, and a frame check sequence (FCS) field. The CTS frame may comprise a frame control field, a duration field, a receiver address (RA) field, and a frame check sequence (FCS) field.

[0120] The TWT protection field in a TWT element may indicate whether a TWT is protected or unprotected. A TWT requesting STA may set the TWT protection field to 1 to request the TWT responding STA to provide protection for the set of TWT SPs. A TWT protection field equal to 1 may indicate to use a NAV protection mechanism to protect access to the medium during the corresponding TWT SPs.

[0121] FIG. 9 illustrates an example 900 of TWT protection in individual TWT operation. As shown in FIG. 9, example 900 includes an AP 910 and a STA 911 .

[0122] In an example, AP 910 may set the TWT protection field to 1 in a TWT response frame to protect the TWT SPs using a NAV protection mechanism. Upon reception of the TWT response frame, STA 91 1 may enter a doze state until the next TWT 930. AP 910 that has set the TWT protection field to 1 may transmit a NAV setting frame at the start of the TWT SP 920. For example, the NAV setting frame may be an RTS frame or a CTS frame.

[0123] A STA that receives the NV setting frame and that is not scheduled to access the medium during the TWT SP 920 may set their NAV according to the NAV setting frame. The STA may not access the medium for the specified amount of time in the NAV setting frame.

[0124] STA 911 may be scheduled to access the medium during the TWT SP 920. STA 91 1 may respond to the RTS frame with a CTS frame. Upon receiving the CTS frame, AP 910 may transmit a downlink frame to STA 911. STA 911 may respond to the downlink frame with a BA frame. When the TWT SP 920 ends, STA 911 may return to the doze state.

[0125] Triggered TXOP sharing (TXS) is a technique introduced in the IEEE 802 1 1 be standard amendment. TXS allows an AP to allocate a time duration within an obtained TXOP to a STA for transmitting one or more non-trigger-based (non-TB) PPDUs. For the TXS procedure, the AP may transmit a multi-user request-to-send (MU-RTS) trigger frame with a triggered TXOP sharing mode subfield set to a non-zero value. The MU-RTS trigger frame is a trigger frame for triggering CTS frame(s) from multiple users. An MU-Docket No.: 24-3051 PCTRTS trigger frame with the triggered TXOP sharing mode subfield set to a non-zero value is called an MU- RTS TXS trigger (MRTT) frame.

[0126] In an example, when the triggered TXOP sharing mode subfield is set to 1 , the STA may transmit the one or more non-TB PPDUs to the AP during the allocated time duration. In an example, when the triggered TXOP sharing mode subfield is set to 2, the STA may transmit the one or more non-TB PPDUs to the AP or a peer STA during the allocated time duration. The peer STA may be a STA with a connection for peer-to-peer (P2P) communication or direct communication with the STA. In an example, the direct wireless link is established according to the tunneled direct link setup (TDLS) protocol.

[0127] FIG. 10 illustrates an example 1000 of a power save (PS) operation in a TWT service period (SP). As shown in FIG. 10, example 1000 includes an AP 1010 and a STA 1011.

[0128] In an example, AP 1010 may be a TWT scheduling AP and STA 1011 may be a TWT scheduled STA. STA 1011 may transmit a TWT request frame to AP 1010, and AP 1010 may respond by transmitting a TWT response frame to STA 101 1. Upon reception of the TWT response frame, STA 1011 may enter a doze state until the next TWT 1030.

[0129] In an example, as discussed above in relation to example 900 illustrated in FIG. 9, AP 1010 may set the TWT protection field to 1 in the TWT response frame to protect the TWT SPs using a NAV protection mechanism. Further, AP 1010 may transmit a NAV setting frame at the start of the TWT SP 1020. For example, the NAV setting frame may be an RTS frame or a GTS frame.

[0130] STA 1011 may be scheduled to access the medium during the TWT SP 1020. STA 101 1 may respond to an RTS frame transmitted by AP 1010 with a GTS frame. Upon receiving the CTS frame, AP 1010 may transmit a downlink PPDU 1040 to STA 101 1.

[0131] In an example, whether the STA 101 1 enters a doze state during TWT SP 1020 may be based on whether downlink PPDU 1040 transmitted by AP 1010 to STA 1011 leads STA 101 1 to detect a TWT SP termination event. For example, a TWT requesting STA, or a TWT scheduled STA, that is not in PS mode and that transmits a frame with a Power Management subfield set to 1 during a TWT SP, may remain in an awake state until a duration (e.g., a duration based on the TWT SP, which may be termed AdjustedMinimumTWTWakeDuration) has elapsed from the TWT SP start time, or until a TWT SP termination event is detected, whichever occurs first for that particular TWT SP. In an example, when a TWT SP termination event is detected within a TWT SP by a STA in PS mode that is participating in the TWT SP, the STA may transition to the doze state without waiting for the expiration of the duration (e g., the AdjustedMinimumTWTWakeDuration time), even if the STA has previously transmitted a PS-Poll frame or U-APSD trigger frame and has not yet received the expected frames from the AP in response.

[0132] A TWT requesting STA or a TWT scheduled STA that is in PS mode and is in an awake state for a TWT SP, may transition to the doze state after a duration (e.g., the AdjustedMinimumTWTWakeDuration) has elapsed from the TWT SP start time. This may be true even if the STA has previously transmitted a PS-Docket No.: 24-3051 PCTPoll frame (e.g., as discussed above in relation to FIGS. 7-9), or another PS frame (e.g., an unscheduled automatic power save delivery (U-APSD) trigger frame), and the STA has not yet received the expected frames from the AP in response. For a trigger-enabled TWT SP, if the duration time has elapsed from the scheduled TWT SP start time and no Trigger frames are received by the STA, the STA may enter doze state if no other condition requires the STA to remain awake.

[0133] A TWT requesting STA or a TWT scheduled STA may classify a number of events as a TWT SP termination event:(a) The transmission by the TWT requesting STA of an acknowledgment in response to an individually addressed QoS Data or QoS Null frame sent by the TWT responding STA that had the EOSP subfield equal to 1 ;(b) The transmission by the TWT scheduled STA of an acknowledgment in response to an individually addressed QoS Data or QoS Null frame sent by the TWT scheduling AP that had the EOSP subfield equal to 1 ;(c) The transmission by the TWT requesting STA of an acknowledgment in response to an individually addressed frame that is neither a QoS Data frame nor a QoS Null frame, but that was sent by the TWT responding STA with the More Data field equal to 0;(d) The transmission by the TWT scheduled STA of an acknowledgment in response to an individually addressed frame that is neither a QoS Data frame nor a QoS Null frame, but that was sent by the TWT scheduling AP with the More Data field equal to 0;(e) The reception of an individually addressed or broadcast QoS Data or QoS Null frame sent by the TWT responding STA or TWT scheduling AP that does not solicit an immediate response and had the EOSP subfield equal to 1 ; or(f) The reception of an individually addressed frame that is neither a QoS Data frame nor a QoS Null frame, but that was sent by the TWT responding STA or TWT scheduling AP, does not solicit an immediate response, and had the More Data field equal to 0.

[0134] In an example, downlink PPDU 1040 may lead STA 1011 to detect a termination event if it meets any of the criteria (a)-(f) above. For example, AP 1010 may set an EOSP subfield of downlink PPDU 1040 to 1. The EOSP subfield is discussed further, above, in relation to FIG. 2. STA 1011 may receive downlink PPDU 1040 and transmit an acknowledgement (e.g., a BlockAck). STA 1011 may classify this as a TWT SP termination event, according to criteria (a), (b), or (e) above. STA 1011 may then enter a doze state, after transmitting the BlockAck and before the end of the TWT SP 1020.

[0135] As another example, a frame (e.g., downlink PPDU 1040) may include a more data subfield. In an example, a non-DMG and non-S1 G STA may use a MD subfield to indicate to a STA in PS mode that more BUs are buffered for that STA at the AP. The MD subfield may be valid in individually addressed Data or Management frames transmitted by an AP to a STA in PS mode. The MD subfield may be set to 1 to indicateDocket No.: 24-3051 PCT that at least one additional buffered BU is present for the same STA. As another example, an AP may optionally set the MD subfield to 1 in Ack frames sent to a non-DMG non-S1 G non-HE STA and in Ack, BlockAck, and Multi-STA BlockAck frames sent to an HE STA. An HE AP may indicate that it supports setting the MD subfield to 1 in these control response frames by setting the MD Ack subfield to 1 in the QoS Info field of elements it includes in frames transmitted to the STA.

[0136] In an example, AP 1010 may set a MD subfield of downlink PPDU 1040 equal to 0, and STA 1011 may receive downlink PPDU 1040 and transmit an acknowledgment. STA 1011 may classify this as a TWT SP termination event according to criteria (c) or (d), above. STA 1011 may then enter a doze state, after transmitting the BlockAck and before the end of the TWT SP 1020.

[0137] FIG. 11 illustrates a further example 1100 of a PS operation in a TWT SP. As illustrated, example 1 100 corresponds to example 1000 discussed above, except example 1 100 illustrates transmission of an uplink PPDU 1142 from STA 1011 to AP 1010, instead of transmission of downlink PPDU 1040 from AP1010 to STA 1011 as in example 1000. AP 1010 may again be a TWT scheduling AP and STA 101 1 may again be a TWT scheduled STA. STA 1011 may transmit a TWT request frame to AP 1010, and AP 1010 may respond by transmitting a TWT response frame to STA 1011. Upon reception of the TWT response frame, STA 1011 may enter a doze state until a next TWT 1130.

[0138] In an example, whether the STA 101 1 enters a doze state during TWT SP 1120 may be based on whether uplink PPDU 1142, transmitted by STA 101 1 to AP 1010, and BA 1112, transmitted by AP 1010 to STA 101 1 in response to uplink PPDU 1 142, lead STA 1011 to detect a TWT SP termination event. As discussed above in relation to example 1000, when a TWT SP termination event is detected within a TWT SP by a STA in PS mode that is participating in the TWT SP, the STA may transition to the doze state without waiting for the expiration of the duration (e.g., the AdjustedMinimumTWTWakeDuration time).

[0139] A TWT SP termination event may include any of events (a) through (f), discussed above. Example 1000 illustrates possible events (a) through (e), while example 1100 illustrates event (f):(f) The reception of an individually addressed frame that is neither a QoS Data frame nor a QoS Null frame, but that was sent by the TWT responding STA or TWT scheduling AP, does not solicit an immediate response, and had the More Data field equal to 0.

[0140] For example, STA 1011 may send an RTS frame during TWT SP 1120, and AP 1010 may respond to the RTS frame with a CTS frame. STA 1011 may then transmit UL PPDU 1142 to AP 1010, and AP 1010 may respond to UL PPDU 1 142 with BA 11 12. In an embodiment, BA 1 112 sets a MD subfield to O. STA101 1 receives BA 1 112 with the MD subfield set to 0, detects a TWT SP termination event (e.g., according to event (f) above), and enters a doze state after receiving BA 1 112 and before the end of TWT SP 1120.

[0141] FIG. 12 illustrates an example that highlights a potential problem that may arise using a dynamic power save (DPS) operation. As shown in FIG. 12, example 1200 includes an AP 1210 and a STA 1220. In an example, STA 1220 is associated with AP 1210, and AP 1210 and STA 1220 support a DPS mode. InDocket No.: 24-3051 PCTDPS mode, a STA may operate using a low capability mode (LCM) or a high capability mode (HCM). In LCM, for example, a STA may be in an awake state and may operate with low power capability related parameters (e.g., using one or more of: a 20MHz bandwidth (BW), one spatial stream (SS), a limited data rate compared with the HCM, a limited PPDU format set compared with the HCM, and a limited control frame set compared with the HCM). For example, a STA operating in LCM may receive a frame that is sent using the low power capability related parameters.

[0142] In HCM, as another example, a STA may also be in an awake state and may operate with high power capability related parameters (e.g., using at least one of an operating BW, a number of spatial stream (NSS), and MCSs that are higher than those in LCM. For example, the higher power capability related parameters may include one or more of: an 80MHz bandwidth, 8 SS, MCS 5~9, EHT / UHR PPDU transmission / reception, data frame / management frame, etc. A STA operating in HCM may receive a frame using the high power capability related parameters, and a STA may transmit a frame to another STA

[0143] As illustrated in example 1200, STA 1220 begins in LCM. AP 1210 transmits an initial control frame (ICF) to STA 1220 while STA 1220 is in LCM. In an example, if a STA receives an ICF for the STA from an AP, the STA transitions from LCM to HCM, and then transmits an ICR to the AP. Thus STA 1220 receives the ICF from AP 1210 (e.g., at least a portion of the ICF), and transitions from LCM to HCM after a state transition time (STT). STA 1220 transmits an initial control response (ICR) to AP 1210, in response to receiving the ICF. In an example, an ICF and / or ICR may be used in a variety of operations (e.g., dynamic power saving, dynamic subband operation, and device coexistence features).

[0144] In an example, after receiving the ICR from STA 1220, AP 1210 may transmit a frame 1212 (e.g., a downlink data frame) to STA 1220 using HCM related parameters. For example, AP 1210 may transmit frame 1212 to STA 1220 using a HCM BW (e.g., greater than 20MHz), multiple spatial streams (e.g., two or more spatial streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types, e.g., HE PPDU, EHT PPDU, UHR PPDU), any frame type, etc. STA 1220 may respond to frame 1212 by transmitting a BA 1222 to AP 1210.

[0145] Further, in an example, AP 1210 may transmit a frame 1214 (e.g., another downlink data frame) to STA 1220. AP 1210 may again use HCM related parameters (e.g., BW, streams, MCS, PPDU type, frame type, etc.) for the transmission of frame 1214. STA 1220 may respond to frame 1214 by transmitting a BA 1224 to AP 1210.

[0146] In an example, STA 1220 may transition from LCM to HCM after receiving at least a portion of the ICF. STA 1220 may then remain in HCM for an ongoing duration, so that STA 1220 may receive frames 1212 and 1214 transmitted by AP 1210 using HCM related parameters. This operation, however, may be energy inefficient as STA 1220 may remain in HCM for longer than necessary. For example, STA 1220 may not know when AP 1210 has completed transmission of additional data frames (e.g., using HCM relatedDocket No.: 24-3051 PCT parameters). As a result, despite implementing the DPS mode described above, STA 1220 may operate in a manner that results in unnecessary overhead and / or high power consumption.

[0147] Embodiments of the present disclosure, as further described below, address the above-described problems of existing technologies. In an aspect, a first STA transitions to a low capability mode of a power save mode. The first STA receives, from an AP, a trigger frame indicating( / allocating) the first STA and, optionally, a second STA. The first STA transitions from the low capability mode to a high capability mode of the power save mode in response to the trigger frame. The first STA transmits, to the AP, an uplink (UL) frame soliciting an acknowledgment frame. In response to the UL frame, the first STA receives, from the AP, the acknowledgment (e.g., a multi-STA BA) frame indicating absence at the AP of a downlink buffered bufferable unit (BU) for the first STA. In an embodiment, the acknowledgement frame is addressed to the first STA and, optionally, to the second STA. Based on receiving the acknowledgment frame, the STA transitions from the high capability mode to the low capability mode. In an embodiment, this transition from the high capability mode to the low capability mode may reduce unnecessary overhead and / or may lower power consumption at the first STA.

[0148] FIG. 13 illustrates an example 1300 according to an embodiment. As shown in FIG. 13, example 1300 includes an AP 1310 and a STA 1320. In an example, STA 1320 is associated with AP 1310. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1310 and STA 1320 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0149] As illustrated in example 1300, STA 1320 begins in LCM. In an embodiment, AP 1310 transmits an ICF to STA 1320 while STA 1320 is in LCM. STA 1320 receives the ICF from AP 1310 (e.g., at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 1320 may transmit an ICR to AP 1310, after transitioning to HCM, in response to receiving the ICF.

[0150] After receiving the ICR from STA 1320, in an embodiment AP 1310 may transmit a frame 1312 (e.g., a downlink data frame) to STA 1320 using HCM related parameters. For example, AP 1310 may transmit frame 1312 to STA 1320 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0151] In an embodiment, AP 1310 may set a MD subfield to 1 in frame 1312. As discussed above in relation to FIG. 10, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 1310 may set the MD subfield to 1 in frame 1312 to indicate to STA 1320 that at least one additional buffered BU is present at AP 1310 for STA 1320.

[0152] In an embodiment, STA 1320 may receive frame 1312 and use the MD subfield to determine whether STA 1320 has finished receiving downlink frames from AP 1310. When a STA finishes receiving downlinkDocket No.: 24-3051 PCT frames from an AP during HCM, in an embodiment the STA may transition from HCM to LCM. An AP may indicate that it has no more downlink data for a STA (e.g., no more buffered BUs for the STA) by transmitting to the STA an individually addressed frame (e.g., a QoS Data frame or a QoS Null frame) with a suitable Ack policy (e.g., an Ack policy set to Implicit BAR (00) or HETP Ack (01 )), that indicates no more data (e.g., a MD subfield set to 0 or an EOSP field set to 1 to indicate the end of a service period).

[0153] In an embodiment, STA 1320 may receive frame 1312 from AP 1310, transmit BA 1322 to AP 1310, and remain in HCM (e.g., based on frame 1312 including a MD subfield set to 1 ). AP 1310 may receive BA 1322 from STA 1320 and may transmit frame 1314 to STA 1320.

[0154] In an embodiment, frame 1314 indicates to STA 1320 that AP 1310 has no more buffered BUs to transmit to STA 1320. For example, frame 1314 may be an individually addressed frame (e.g., a QoS Data frame or a QoS Null frame with an Ack policy equal set to Implicit BAR (00) or HETP Ack(01 )), with a MD subfield set to 0. In an embodiment, STA 1320 may receive frame 1314, indicating that AP 1310 has no more buffered BUs to transmit to STA 1320, and may transmit a BA 1324 in response to frame 1314. STA 1320 may then transition from HCM to LCM (e.g., after a STT). In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 1320 to remain in HCM when AP 1310 has additional BUs to transmit to STA 1320, and allowing STA 1320 to transition to LCM when AP 1310 has no more buffered BUs to transmit to STA 1320.

[0155] In another embodiment, frame 1314 may be a CF-End frame to truncate / end a DL TXOP. In an example, the DL TXOP may be initiated by AP 1310 using an ICF frame. In an embodiment, STA 1320 may not transmit BA 1324 in response to receiving the CF-End frame (e.g., frame 1314). In an embodiment, STA 1320 may receive frame 1314, and may transition from HCM to LCM in response to / after receiving frame 1314 (e.g., without transmitting BA 1324). In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 1320 to transition to LCM when AP 1310 has truncated the DL TXOP.

[0156] FIG. 14 illustrates an example 1400 according to an embodiment. As shown in FIG. 14, example 1400 includes an AP 1410 and a STA 1420. In an example, STA 1420 is associated with AP 1410. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1410 and STA 1420 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0157] As illustrated in example 1400, STA 1420 begins in LCM. In an embodiment, AP 1410 transmits an ICF to STA 1420 while STA 1420 is in LCM. STA 1420 receives the ICF from AP 1410 (e.g., at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 1420 may transmit an ICR to AP 1410, after transitioning to HCM, in response to receiving the ICF.

[0158] After receiving the ICR from STA 1420, in an embodiment AP 1410 may transmit a frame 1412 (e.g., a downlink data frame) to STA 1420 using HCM related parameters. For example, AP 1410 may transmit frame 1412 to STA 1420 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or moreDocket No.: 24-3051 PCT streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0159] In an embodiment, AP 1410 may indicate in frame 1412 that no more data frames (e.g., no more buffered BUs) for STA 1420 are present at AP 1410. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may indicate that it has no more downlink data for a STA (e.g., no more buffered BUs for the STA) by transmitting to the STA an individually addressed frame (e.g., a QoS Data frame or a QoS Null frame) with a suitable Ack policy (e.g., an Ack policy set to Implicit BAR (00) or HETP Ack (01)), that indicates no more data (e.g., a MD subfield set to 0 or an EOSP field set to 1 to indicate the end of a service period).

[0160] In an embodiment, AP 1410 sets a MD subfield to 0 in frame 1412. STA 1420 may receive frame 1412, indicating that AP 1410 has no more buffered BUs to transmit to STA 1420. In an embodiment, STA 1420 may transition from HCM to LCM after receiving frame 1412, and before transmitting an acknowledgment in response to frame 1412. For example, frame 1412 may be an individually addressed frame indicating no more data by including a MD subfield set to 0, and may have an Ack policy set to no ack (e.g., 10) or BA (11). After receiving frame 1412, STA may transition from HCM to LCM (e.g., after a STT), before sending an acknowledgment for frame 1412. In an embodiment, this transition from HCM to LCM, before sending an acknowledgment, may reduce unnecessary overhead and / or lower power consumption by allowing STA 1420 to transition to LCM when AP 1410 has no more buffered BUs to transmit to STA 1420, while reducing overhead and power consumption that would have come from transmitting an acknowledgment before transitioning from HCM to LCM.

[0161] FIG. 15 illustrates an example 1500 according to an embodiment. As shown in FIG. 15, example 1500 includes an AP 1510 and a STA 1520. In an example, STA 1520 is associated with AP 1510. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1510 and STA 1520 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0162] As illustrated in example 1500, STA 1520 begins in LCM. In an embodiment, during a TXOP 1502 AP 1510 transmits an ICF 1512 to STA 1520 while STA 1520 is in LCM. STA 1520 receives ICF 1512 from AP 1510 (e.g., at least a portion of ICF 1512), and may transition from LCM to HCM after a STT. STA 1520 may transmit an ICR 1522 to AP 1510, after transitioning to HCM, in response to receiving ICF 1512.

[0163] After receiving ICR 1522 from STA 1520, in an embodiment AP 1510 may transmit a frame 1514 (e.g , a downlink data frame) to STA 1520, during TXOP 1502, using HCM related parameters. For example, AP 1510 may transmit frame 1514 to STA 1520 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0164] In an embodiment, AP 1510 may indicate in frame 1514 that additional data frames (e.g., at least one additional buffered BU) for STA 1520 are present at AP 1510. For example, as discussed above inDocket No.: 24-3051 PCT relation to example 1300 illustrated in FIG. 13, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 1510 may set the MD subfield to 1 in frame 1514 to indicate to STA 1520 that at least one additional buffered BU is present at AP 1510 for STA 1520.

[0165] In an embodiment, STA 1520 may receive frame 1514 from AP 1510, transmit BA 1524 to AP 1510, and remain in HCM (e.g., based on frame 1514 including a MD subfield set to 1 ). After the end of TXOP 1502, however, in an embodiment STA 1520 may transition from HCM to LCM (e.g., after a STT). For example, at the end of a TXOP a STA in HCM may transition from HCM to LCM, regardless of whether an AP indicated in previous frames that the AP had additional data for the STA. Thus, as illustrated, STA 1520 transitions from HCM to LCM at the end of TXOP 1502, even though frame 1514 includes a MD subfield set to 1 to indicate that AP 1510 has additional data frames (e.g., additional BUs) for STA 1520.

[0166] As illustrated in example 1500, a TXOP 1504 begins with STA 1520 in LCM. In an embodiment, during TXOP 1504 AP 1510 transmits another ICF 1516 to STA 1520 while STA 1520 is in LCM. STA 1520 receives ICF 1516 from AP 1510 (e.g., at least a portion of ICF 1516), and may transition from LCM to HCM after a STT. STA 1520 may transmit an ICR 1526 to AP 1510, after transitioning to HCM, in response to receiving ICF 1516.

[0167] After receiving ICR 1526 from STA 1520, in an embodiment AP 1510 may transmit a frame 1518 (e.g., a downlink data frame) to STA 1520, during TXOP 1504, using HCM related parameters. For example, AP 1510 may transmit frame 1518 to STA 1520 using a HCM BW (e.g , greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0168] In an embodiment, AP 1510 may indicate in frame 1518 that that no more data frames (e.g., no more buffered BUs) for STA 1520 are present at AP 1510. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may indicate that it has no more downlink data for a STA (e.g., no more buffered BUs for the STA) by transmitting to the STA an individually addressed frame (e.g., a QoS Data frame or a QoS Null frame) with a suitable Ack policy (e.g., an Ack policy set to Implicit BAR (00) or HETP Ack (01 )), that indicates no more data (e.g., a MD subfield set to 0 or an EOSP field set to 1 to indicate the end of a service period).

[0169] In an embodiment, AP 1510 sets a MD subfield to 0 in frame 1518. STA 1520 may receive frame 1518, indicating that AP 1510 has no more buffered BUs to transmit to STA 1520. STA 1520 may transmit a BA 1528 to AP 1510, in response to frame 1518. In an embodiment, TXOP 1504 ends and STA 1520 transitions from HCM to LCM (e.g., after a STT). As discussed above, in an embodiment a STA in HCM may transition from HCM to LCM at the end of a TXOP, regardless of whether an AP indicated in previous framesDocket No.: 24-3051 PCT that the AP had additional data for the STA. Thus, as illustrated, STA 1520 may transition from HCM to LCM at the end of TXOP 1504, regardless of the MD subfield in frame 1518. In an embodiment, this may reduce unnecessary overhead and / or lower power consumption by allowing STA 1520 to transition to LCM at the end of a TXOP.

[0170] FIG. 16 illustrates an example operation according to an embodiment. As shown in FIG. 16, example 1600 includes an AP 1610 and a STA 1620. In an example, STA 1620 is associated with AP 1610. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1610 and STA 1620 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0171] As illustrated in example 1600, STA 1620 begins in LCM. In an embodiment, during a TXOP 1602 AP 1610 transmits an ICF to STA 1620 while STA 1620 is in LCM. STA 1620 receives the ICF from AP 1610 (e.g . , at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 1620 may transmit an ICR to AP 1610, after transitioning to HCM, in response to receiving the ICF.

[0172] After receiving the ICR from STA 1620, in an embodiment AP 1610 may transmit a frame 1612 (e.g., a downlink data frame) to STA 1620, during TXOP 1602, using HCM related parameters. For example, AP 1610 may transmit frame 1612 to STA 1620 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0173] In an embodiment, AP 1610 may indicate in frame 1612 that additional data frames (e.g., at least one additional buffered BU) for STA 1620 are present at AP 1610. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 1610 may set the MD subfield to 1 in frame 1612 to indicate to STA 1620 that at least one additional buffered BU is present at AP 1610 for STA 1620.

[0174] In an embodiment, STA 1620 may receive frame 1612 from AP 1610, transmit BA 1622 to AP 1610, and remain in HCM (e.g., based on frame 1612 including a MD subfield set to 1). As illustrated, TXOP 1602 ends after STA 1620 transmits BA 1622 to AP 1610. In an embodiment, and in contrast to STA 1520 illustrated in example 1500, STA 1620 may continue to remain in HCM after the end of TXOP 1602 based on the last frame received in TXOP 1602 (e.g., frame 1612) indicating that at least one additional data frame is present at AP 1610 for STA 1620. In an embodiment, a STA may remain in HCM after conclusion of a TXOP if an AP indicates, during the TXOP, that the AP has additional data for the STA.

[0175] As illustrated, a TXOP 1604 begins after TXOP 1602 concludes. AP 1610 may transmit a frame 1614 (e.g., a downlink data frame) to STA 1620, during TXOP 1604, again using HCM related parameters. In an embodiment, AP 1610 may again indicate in frame 1614 that additional data frames (e.g., at least oneDocket No.: 24-3051 PCT additional buffered BU) for STA 1620 are present at AP 1610. In an embodiment, AP 1610 may set the MD subfield to 1 in frame 1614 to indicate to STA 1620 that at least one additional buffered BU is present at AP 1610 for STA 1620.

[0176] In an embodiment, STA 1620 may receive frame 1614 from AP 1610, transmit BA 1624 to AP 1610, and remain in HCM (e.g., based on frame 1614 including a MD subfield set to 1). As illustrated, TXOP 1604 ends after STA 1620 transmits BA 1622 to AP 1610. In an embodiment, based on frame 1614 indicating that AP 1610 has at least one additional data frame (e.g., at least one additional buffered BU), STA 1620 may again continue to remain in HCM after the end of TXOP 1604 based on the last frame received in TXOP 1604 (e.g., frame 1614) indicating that at least one additional data frame is present at AP 1610 for STA 1620.

[0177] In example 1600, a TXOP 1606 begins after TXOP 1604 concludes. AP 1610 may transmit an RTS frame 1616 to STA 1620, and STA 1620 may reply to the RTS frame 1616 by transmitting a CTS frame 1626 to AP 1610. After receiving the CTS frame 1626, AP 1610 may transmit a frame 1618 (e.g., a downlink data frame) to STA 1620, during TXOP 1606, again using HCM related parameters.In an embodiment, AP 1610 may indicate in frame 1618 that no more data frames (e.g., no more buffered BUs) for STA 1620 are present at AP 1610. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may indicate that it has no more downlink data for a STA (e.g., no more buffered BUs for the STA) by transmitting to the STA an individually addressed frame (e.g., a QoS Data frame or a QoS Null frame) with a suitable Ack policy (e.g., an Ack policy set to Implicit BAR (00) or HETP Ack (01)), that indicates no more data (e.g., a MD subfield set to 0 or an EOSP field set to 1 to indicate the end of a service period).

[0178] In an embodiment, AP 1610 sets a MD subfield to 0 in frame 1618. STA 1620 may receive frame 1618, indicating that AP 1610 has no more buffered BUs to transmit to STA 1620. STA 1620 may transmit a BA 1628 to AP 1610, in response to frame 1618. STA 1620 may then transition from HCM to LCM (e.g., after a STT). In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 1620 to remain in HCM when AP 1610 has additional BUs to transmit to STA 1620, across TXOPs, and allowing STA 1620 to transition to LCM when AP 1610 has no more buffered BUs to transmit to STA 1620.

[0179] FIG. 17 illustrates an example 1700 according to an embodiment. As shown in FIG. 17, example 1700 includes an AP 1710 and a STA 1720. In an example, STA 1720 is associated with AP 1710. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1710 and STA 1720 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0180] As illustrated in example 1700, STA 1720 begins in LCM. In an embodiment, during a TXOP 1702 AP 1710 transmits an ICF to STA 1720 while STA 1720 is in LCM. STA 1720 receives the IGF from AP 1710 (e.g., at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 1720 may transmit an ICR to AP 1710, after transitioning to HCM, in response to receiving the ICF.Docket No.: 24-3051 PCT

[0181] After receiving the ICR from STA 1720, in an embodiment AP 1710 may transmit a frame 1712 (e.g., a downlink data frame) to STA 1720, during TXOP 1702, using HCM related parameters. For example, AP 1710 may transmit frame 1712 to STA 1720 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0182] In an embodiment, AP 1710 may indicate in frame 1712 that additional data frames (e.g., at least one additional buffered BU) for STA 1720 are present at AP 1710. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 1710 may set the MD subfield to 1 in frame 1712 to indicate to STA 1720 that at least one additional buffered BU is present at AP 1710 for STA 1720.

[0183] In an embodiment, STA 1720 may receive frame 1712 from AP 1710, transmit BA 1722 to AP 1710, and remain in HCM (e.g., based on frame 1712 including a MD subfield set to 1). As illustrated, TXOP 1702 ends after STA 1720 transmits BA 1722 to AP 1710. In an embodiment, like example 1600 illustrated in FIG. 16, STA 1720 may continue to remain in HCM after the end of TXOP 1702 based on the last frame received in TXOP 1702 (e.g., frame 1712) indicating that at least one additional data frame is present at AP 1710 for STA 1720. In an embodiment, a STA may remain in HCM after conclusion of a TXOP if an AP indicates, during the TXOP, that the AP has additional data for the STA.

[0184] In an embodiment, AP 1710 may not obtain a TXOP immediately after TXOP 1702 concludes. Thus, AP 1710 may not transmit any data frames to STA 1720 immediately after TXOP 1702 concludes, while STA 1720 is in HCM. In an embodiment, STA 1720 may remain in HCM for a first period after transmitting BA 1722, waiting to receive an additional frame from AP 1710, and then may transition to LCM (e.g., after a STT) after the first period expires. For example, the first period may be a duration in which STA 1720 remains in HCM and waits for an additional frame, after STA 1720 has received or transmitted its last frame. In an embodiment, the first period may be indicated by a STA to an AP (e.g., by transmitting a frame from the STA to the AP including the first period), or by an AP to a STA (e.g., by transmitting or announcing a frame indicating the first period to the STA). For example, the first period may be indicated as part of a negotiation between the STA and AP. During the negotiation, the STA (or AP) may transmit a frame indicating the first period after receiving another proposed period from the AP (or STA). The first period used after the negotiation may be different (e.g., shorter or longer) from an earlier proposed period in the negotiation. Further, in an embodiment, the first period may have a fixed value and be pre-determined (e.g., included in an IEEE 802.11 standard document). In an embodiment, an AP may not transmit an IGF (e.g., an RTS, MU- RTS, BSRP, BAR, etc.) to a STA during the first period.Docket No.: 24-3051 PCT

[0185] If the first period expires without the STA 1720 receiving an additional frame from AP 1710, STA 1720 may transition from HCM to LCM. In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 1720 to transition from HCM to LCM if AP 1710 does not obtain a TXOP to transmit remaining data frames to STA 1720.

[0186] FIG. 18 illustrates an example 1800 according to an embodiment. As shown in FIG. 18, example 1800 includes an AP 1810 and a STA 1820. In an example, STA 1820 is associated with AP 1810. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1810 and STA 1820 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0187] As illustrated in example 1800, STA 1820 begins in LCM. In an embodiment, during a TXOP 1802 AP 1810 transmits an ICF to STA 1820 while STA 1820 is in LCM. STA 1820 receives the ICF from AP 1810 (e.g . , at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 1820 may transmit an ICR to AP 1810, after transitioning to HCM, in response to receiving the ICF.

[0188] After receiving the ICR from STA 1820, in an embodiment AP 1810 may transmit a frame 1812 (e.g., a downlink data frame) to STA 1820, during TXOP 1802, using HCM related parameters. For example, AP 1810 may transmit frame 1812 to STA 1820 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0189] In an embodiment, AP 1810 may indicate in frame 1812 that additional data frames (e.g., at least one additional buffered BU) for STA 1820 are present at AP 1810. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 1810 may set the MD subfield to 1 in frame 1812 to indicate to STA 1820 that at least one additional buffered BU is present at AP 1810 for STA 1820.

[0190] In an embodiment, STA 1820 may receive frame 1812 from AP 1810, transmit BA 1822 to AP 1810, and remain in HCM (e.g., based on frame 1812 including a MD subfield set to 1). As illustrated, TXOP 1802 ends after STA 1820 transmits BA 1822 to AP 1810. In an embodiment, like example 1600 illustrated in FIG. 16, STA 1820 may continue to remain in HCM after the end of TXOP 1802 based on the last frame received in TXOP 1802 (e.g , frame 1812) indicating that at least one additional data frame is present at AP 1810 for STA 1820. In an embodiment, a STA may remain in HCM after conclusion of a TXOP if an AP indicates, during the TXOP, that the AP has additional data for the STA.

[0191] In an embodiment, AP 1810 may not obtain a TXOP immediately after TXOP 1802 concludes. Thus, AP 1810 may not transmit any data frames to STA 1820 immediately after TXOP 1802 concludes, while STA 1820 is in HCM. In an embodiment, like STA 1720 in example 1700 illustrated in FIG. 17, STA 1820 mayDocket No.: 24-3051 PCT remain in HCM for a first period after transmitting BA 1822, waiting to receive an additional frame from AP 1810, and then may transition to LCM (e.g. , after a STT) after the first period expires. For example, the first period may be a duration, in which STA 1820 remains in HCM and waits for an additional frame, after STA 1820 has received or transmitted its last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an ICF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0192] In an embodiment, AP 1810 transmits frame 1814, to a STA2 (e.g., a STA, other than STA 1820, associated with AP 1810), during the first period. Further, in an embodiment, STA 1820 may receive frame 1814 and identify frame 1814 as intended for STA2 (and not STA 1820). In an embodiment, STA 1820 may transition from HCM to LCM when STA 1820 receives a frame from AP 1810 addressed to another STA (e g., other than STA 1820). For example, as illustrated, STA 1820 receives frame 1814 during the first period, and begins to transition from HCM to LCM, after receiving frame 1814 and before the first period expires.

[0193] Further, in an embodiment, STA 1820 may use a TXOP duration and / or PPDU duration indicated in frame 1814 to determine whether to transition from HCM to LCM. For example, STA 1820 may receive frame 1814 and determine that frame 1814 is intended for STA2. But, in an embodiment, STA 1820 may transition from HCM to LCM only if STA 1820 determines that the TXOP duration and / or PPDU duration indicated in frame 1814 exceeds the first period. In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 1820 to transition from HCM to LCM if AP 1810 transmits a frame to a different STA instead of STA 1820.

[0194] FIG. 19 illustrates an example 1900 according to an embodiment. As shown in FIG. 19, example 1900 includes an AP 1910 and a STA 1920. In an example, STA 1920 is associated with AP 1910. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 1910 and STA 1920 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0195] As illustrated in example 1900, STA 1920 begins in LCM. In an embodiment, during a TXOP 1902 AP 1910 transmits an ICF to STA 1920 while STA 1920 is in LCM. STA 1920 receives the ICF from AP 1910 (e.g., at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 1920 may transmit an ICR to AP 1910, after transitioning to HCM, in response to receiving the ICF.

[0196] After receiving the ICR from STA 1920, in an embodiment AP 1910 may transmit a frame 1912 (e g., a downlink data frame) to STA 1920, during TXOP 1902, using HCM related parameters. For example, AP 1910 may transmit frame 1912 to STA 1920 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.Docket No.: 24-3051 PCT

[0197] In an embodiment, AP 1910 may indicate in frame 1912 that additional data frames (e.g., at least one additional buffered BU) for STA 1920 are present at AP 1910. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 1910 may set the MD subfield to 1 in frame 1912 to indicate to STA 1920 that at least one additional buffered BU is present at AP 1910 for STA 1920.

[0198] In an embodiment, STA 1920 may receive frame 1912 from AP 1910, transmit BA 1922 to AP 1910, and remain in HCM (e.g., based on frame 1912 including a MD subfield set to 1). As illustrated, TXOP 1902 ends after STA 1920 transmits BA 1922 to AP 1910. In an embodiment, like example 1600 illustrated in FIG. 16, STA 1920 may continue to remain in HCM after the end of TXOP 1902 based on the last frame received in TXOP 1902 (e.g., frame 1912) indicating that at least one additional data frame is present at AP 1910 for STA 1920. In an embodiment, a STA may remain in HCM after conclusion of a TXOP if an AP indicates, during the TXOP, that the AP has additional data for the STA.

[0199] In an embodiment, AP 1910 may not obtain a TXOP immediately after TXOP 1902 concludes. Thus, AP 1910 may not transmit any data frames to STA 1920 immediately after TXOP 1902 concludes, while STA 1920 is in HCM. In an embodiment, like STA 1720 in example 1700 illustrated in FIG. 17, STA 1920 may remain in HCM for a first period after transmitting BA 1922, waiting to receive an additional frame from AP 1910, and then may transition to LCM (e.g., after a STT) after the first period expires. For example, the first period may be a duration in which STA 1920 remains in HCM and waits for an additional frame, after STA 1920 has received or transmitted its last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an ICF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0200] In an embodiment, AP 1910 transmits frame 1914, to a STA2 (e.g., a STA, other than STA 1920, associated with AP 1910), during the first period. Further, in an embodiment, STA 1920 may receive frame 1914 and identify frame 1914 as intended for STA2 (and not STA 1920). In an embodiment, like STA 1820 in example 1800 illustrated in FIG. 18, STA 1920 may transition from HCM to LCM when STA 1920 both receives a frame from AP 1910 addressed to another STA (e.g., other than STA 1920), and determines that the TXOP duration and / or PPDU duration indicated in frame 1914 exceeds the first period.

[0201] As illustrated, STA 1920 determines that the TXOP and / or PPDU duration indicated in frame 1914 does not exceed the first period, and so STA 1920 remains in HCM after receiving frame 1914. AP 1910 receives BA 1916, from STA2 in response to transmitting frame 1914, during the first period. AP 1910 thenDocket No.: 24-3051 PCT transmits frame 1918, to STA 1920, during the first period. STA 1920 has remained in HCM, and so STA 1920 receives frame 1918 from AP 1910 and transmits a BA 1924 to AP 1910. In an embodiment, a STA (e.g., STA 1920) remaining in HCM may reduce unnecessary overhead and increase throughput by allowing the STA to receive a data frame transmitted using HCM related parameters (e.g., frame 1918).

[0202] FIG. 20 illustrates an example 2000 according to an embodiment. As shown in FIG. 20, example 2000 includes an AP 2010 and a STA 2020. In an example, STA 2020 is associated with AP 2010. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2010 and STA 2020 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0203] As illustrated in example 2000, STA 2020 begins in LCM. In an embodiment, during a TXOP 2002 AP 2010 transmits an ICF to STA 2020 while STA 2020 is in LCM. STA 2020 receives the ICF from AP 2010 (e.g., at least a portion of the ICF), and may transition from LCM to HCM after a STT. STA 2020 may transmit an ICR to AP 2010, after transitioning to HCM, in response to receiving the ICF.

[0204] After receiving the ICR from STA 2020, in an embodiment AP 2010 may transmit a frame 2012 (e.g., a downlink data frame) to STA 2020, during TXOP 2002, using HCM related parameters. For example, AP 2010 may transmit frame 2012 to STA 2020 using a HCM BW (e.g., greater than 20MHz), multiple streams (e.g., two or more streams), a relatively high MCS (e.g., an MCS from 3-9), any PPDU type (e.g., not merely LCM related PPDU types), any frame, etc.

[0205] In an embodiment, AP 2010 may indicate in frame 2012 that additional data frames (e.g., at least one additional buffered BU) for STA 2020 are present at AP 2010. For example, as discussed above in relation to example 1300 illustrated in FIG. 13, an AP may include a MD subfield in a frame transmitted to a STA to indicate to the STA that more BUs are buffered for that STA at the AP. The MD subfield may be set to 1 to indicate that at least one additional buffered BU is present for the STA, and may be set to 0 to indicate that no additional buffered BUs are present for the STA. Thus, in an embodiment, AP 2010 may set the MD subfield to 1 in frame 2012 to indicate to STA 2020 that at least one additional buffered BU is present at AP 2010 for STA 2020.

[0206] In an embodiment, STA 2020 may receive frame 2012 from AP 2010, transmit BA 2022 to AP 2010, and remain in HCM (e.g., based on frame 2012 including a MD subfield set to 1). As illustrated, TXOP 2002 ends after STA 2020 transmits BA 2022 to AP 2010. In an embodiment, like example 1600 illustrated in FIG. 16, STA 2020 may continue to remain in HCM after the end of TXOP 2002 based on the last frame received in TXOP 2002 (e.g , frame 2012) indicating that at least one additional data frame is present at AP 2010 for STA 2020. In an embodiment, a STA may remain in HCM after conclusion of a TXOP if an AP indicates, during the TXOP, that the AP has additional data for the STA.

[0207] In an embodiment, AP 2010 may not obtain a TXOP immediately after TXOP 2002 concludes. Thus, AP 2010 may not transmit any data frames to STA 2020 immediately after TXOP 2002 concludes, while STA 2020 is in HCM. In an embodiment, like STA 1720 in example 1700 illustrated in FIG. 17, STA 2020 mayDocket No.: 24-3051 PCT remain in HCM for a first period after transmitting BA 2022, waiting to receive an additional frame from AP 2010, and then may transition to LCM (e.g. , after a STT) after the first period expires. For example, the first period may be a duration, in which STA 2020 remains in HCM and waits for an additional frame, after STA 2020 has received or transmitted its last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an ICF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0208] In an embodiment, AP 2010 transmits frame 2014, to a STA2 (e.g., a STA, other than STA 2020, associated with AP 2010), during the first period. Further, in an embodiment, STA 2020 may receive frame 2014 and identify frame 2014 as intended for STA2 (and not STA 2020). In an embodiment, like STA 1820 in example 1800 illustrated in FIG. 18, STA 2020 may transition from HCM to LCM when STA 2020 both receives a frame from AP 2010 addressed to another STA (e.g., other than STA 2020), and determines that the TXOP duration and / or PPDU duration indicated in frame 2014 exceeds the first period.

[0209] As illustrated, STA 2020 determines that the TXOP and / or PPDU duration indicated in frame 2014 does not exceed the first period, and so STA 2020 remains in HCM after receiving frame 2014. AP 2010 receives BA 2016, from STA2 in response to transmitting frame 2014, during the first period. The first period then expires, before AP 2010 transmits any additional frames (e.g., before AP 2010 transmits an additional data frame to STA 2020). In an embodiment, STA 2020 may transition from HCM to LCM after the first period expires (e.g., after a STT). For example, a STA may transition from HCM to LCM after the first period expires, if the STA does not receive from its associated AP a frame addressed to that STA during the first time period. In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 2020 to transition from HCM to LCM if AP 2010 has not transmitted a data frame to STA 2020 within a time period of the TXOP expiring.

[0210] FIG. 21 illustrates an example 2100 according to an embodiment. As shown in FIG. 21 , example 2100 includes an AP 21 10 and a STA 2120. In an example, STA 2120 is associated with AP 2110. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 21 10 and STA 2120 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0211] As illustrated in example 2100, STA 2120 begins in HCM. In an embodiment, STA 2120 may initiate an uplink transmission to AP 2110 by transmitting an RTS or ICF frame to AP 21 10. AP 2110 receives the RTS / CTS frame and transmits a CTS or ICR frame in response. For example, if STA 2120 transmits an RTS frame to AP 2110, AP 2110 may transmit a CTS frame in response. As another example, if STA 2120 transmits an ICF to AP 2110, AP 2110 may transmit an ICR frame in response.

[0212] STA 2120 may receive the CTS / ICR frame and transmit a frame 2122 (e.g., an uplink data frame) to AP 2110. AP 2110 may receive frame 2122 and transmit a frame 21 12 (e.g., an Ack or BA frame), to STADocket No.: 24-3051 PCT2120, in response. In an embodiment, AP 2110 may indicate in frame 2112 whether AP 2110 has additional downlink data frames buffered for STA 2120. For example, an AP may indicate that it has no more downlink data for a STA (e.g., no more buffered BUs for the STA) by transmitting to the STA an individually addressed immediate response frame (e.g., an Ack, BA, or M-BA) that indicates no more data (e.g., a MD subfield set to 0).

[0213] In an embodiment, AP 2110 sets a MD subfield to 0 in frame 2112. STA 2120 may receive frame 2112, indicating that AP 2110 has no more buffered BUs to transmit to STA 2120. In an embodiment, STA 2120 may transition from HCM to LCM after receiving frame 2112 (e.g., before transmitting an acknowledgment for frame 2112). In an embodiment, this transition from HCM to LCM, before sending an acknowledgment, may reduce unnecessary overhead and / or lower power consumption by allowing STA 2120 to transition to LCM when AP 2110 has no more buffered BUs to transmit to STA 2120, without requiring STA 2120 to transmit an acknowledgement before transitioning from HCM to LCM.

[0214] In another embodiment, STA 2120 may transmit an additional frame after receiving frame 2112 and before transitioning from HCM to LCM. For example, STA 2120 may transmit a CF-End frame (not illustrated), truncating an UL TXOP, a SIFS after receiving frame 2112 (e.g., an Ack or BA frame), and STA 2120 may transition from HCM to LCM after transmitting the CF-End frame. In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 2120 to transition to LCM when AP 2110 has no more buffered BUs to transmit to STA 2120.

[0215] FIG. 22 illustrates an example 2200 according to an embodiment. As shown in FIG. 22, example 2200 includes an AP 2210, a STA 2220, and another STA 2230. In an example, STAs 2220 and 2230 are associated with AP 2210. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2210 and STAs 2220 and 2230 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0216] As illustrated in example 2200, STAs 2220 and 2230 each begin in LCM. In an embodiment, AP 2210 may transmit a Buffer Status Report (BSR) Poll (BSRP) trigger frame to STAs 2220 and 2230. STA 2220 receives the BSRP trigger frame from AP 2210 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2220 may transmit a BSR 2222 to AP 2210, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2230 also receives the BSRP trigger frame from AP 2210 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2230 may transmit a BSR 2232 to AP 2210, after transitioning to HCM, in response to receiving the BSRP trigger frame.

[0217] In an embodiment, STA 2220 may indicate in BSR 2222 that STA 2220 has uplink data for transmission to AP 2210. Further, in an embodiment, STA 2230 may indicate in BSR 2232 that STA 2230 does not have uplink data for transmission to AP 2210. AP 2210 may transmit a TF to STA 2220. STA 2220 may receive the TF, and may transmit a frame 2224 (e.g., an uplink data frame) to AP 2210.Docket No.: 24-3051 PCT

[0218] In an embodiment, AP 2210 may receive frame 2224 and transmit a frame 2212 (e.g. , an Ack, BA, or M-BA frame), to STA 2220, in response. In an embodiment, AP 2210 may indicate in frame 2212 whether AP 2210 has additional downlink data frames buffered (e.g., for STA 2220 or for all associated STAs). For example, an AP may indicate that it has no more downlink data for a STA (e.g., no more buffered BUs for the STA) by transmitting to the STA a response frame (e.g., an Ack, BA, or M-BA) that indicates no more data (e.g., a MD subfield set to 0).

[0219] In an embodiment, AP 2210 sets a MD subfield to 0 in frame 2212. STA 2220 may receive frame 2212, indicating that AP 2210 has no more buffered BUs to transmit to STA 2220. In an embodiment, STA 2220 may transition from HCM to LCM after receiving frame 2212 (e.g., before transmitting an acknowledgment for frame 2212). Further, in an embodiment, STA 2230 may also receive frame 2212, and frame 2212 may indicate that AP 2210 also has no BUs to transmit to STA 2230. In an embodiment, STA 2230 may transition from HCM to LCM after receiving frame 2212. In an embodiment, this transition from HCM to LCM, for STA 2220, STA 2230, or both, may reduce unnecessary overhead and / or lower power consumption by allowing one or more of the STAs to transition to LCM when AP 2210 has no more buffered BUs to transmit to the STAs.

[0220] In another embodiment, STA 2220 may transmit an additional frame after receiving frame 2212 and before transitioning from HCM to LCM. For example, STA 2220 may transmit a CF-End frame (not illustrated), truncating an UL TXOP, a SIFS after receiving frame 2212 (e.g., an Ack, BA, or M-BA frame), and STA 2220 may transition from HCM to LCM after transmitting the CF-End frame. In an embodiment, this transition from HCM to LCM may reduce unnecessary overhead and / or lower power consumption by allowing STA 2220 to transition to LCM when AP 2210 has no more buffered BUs to transmit to STA 2220.

[0221] FIG. 23 illustrates an example 2300 according to an embodiment. As shown in FIG. 23, example 2300 includes an AP 2310, a STA 2320, and another STA 2330. In an example, STAs 2320 and 2330 are associated with AP 2310. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2310 and STAs 2320 and 2330 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0222] As illustrated in example 2300, STAs 2320 and 2330 each begin in LCM. In an embodiment, AP 2310 may transmit a BSRP to STAs 2320 and 2330. STA 2320 receives the BSRP from AP 2310 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2320 may transmit a BSR 2322 to AP 2310, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2330 also receives the BSRP from AP 2310 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2330 may transmit a BSR 2332 to AP 2310, after transitioning to HCM, in response to receiving the BSRP.

[0223] In an embodiment, STA 2320 may indicate in BSR 2322 that STA 2320 has uplink data for transmission to AP 2310. Further, in an embodiment, STA 2330 may also indicate in BSR 2332 that STADocket No.: 24-3051 PCT2330 has uplink data for transmission to AP 2310. AP 2310 may transmit a TF to STAs 2320 and 2330. STA 2320 may receive the TF, and may transmit a frame 2324 (e.g., an uplink data frame) to AP 2310. STA 2320 may also receive the TF, and may transmit a frame 2334 (e.g., an uplink data frame) to AP 2310.

[0224] In an embodiment, AP 2310 may receive frames 2324 and 2334 and may transmit a frame 2312 to both STA 2320 and STA 2330 (e.g., a M-BA frame with a RA field set to broadcast). In an embodiment, AP 2310 may indicate in frame 2312 whether AP 2310 has additional downlink data frames buffered (e.g., for STA 2320, STA 2330, or both).

[0225] For example, AP 2310 may set a MD subfield of frame 2312 to 1 to indicate when AP 2310 has at least one BU for at least one STA (e.g., at least one STA indicated in an association identifier (AID) traffic identifier (TID) info subfield of an M-BA frame). As another example, AP 2310 may set a MD subfield of frame 2312 to 1 to indicate when AP 2310 has at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0226] As another example, AP 2310 may set a MD subfield of frame 2312 to 0 to indicate when AP 2310 does not have at least one BU for at least one STA (e.g., at least one STA indicated in an AID TID Info subfield of an M-BA frame). As a further example, AP 2310 may set a MD subfield of frame 2312 to 0 to indicate when AP 2310 does not have at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0227] In an embodiment, a STA receiving a response frame (e.g., a M-BA with a RA set to broadcast) from an AP with a MD subfield set to 0 may transition to LCM. Otherwise, if a MD subfield is set to 1 , a STA receiving the response frame will maintain HOM. Further, in an embodiment, a response frame (e.g., a M- BA) may include a field indicating whether a MD subfield is valid. In this embodiment, a STA receiving a response frame will only use the MD subfield to determine whether to transition from HCM to LCM if the MD valid field is set. Alternatively, where a response frame does not include a MD valid field, a receiving STA may always use the MD subfield to determine whether to transition from HCM to LCM.

[0228] In an embodiment, AP 2310 sets a MD subfield to 0 in frame 2312. STA 2320 may receive frame 2312, indicating that AP 2310 has no more buffered BUs to transmit to STA 2320. In an embodiment, STA 2320 may transition from HCM to LCM after receiving frame 2312 (e.g., before transmitting an acknowledgment for frame 2312). Further, in an embodiment, STA 2330 may also receive frame 2312, and frame 2312 may indicate that AP 2310 also has no BUs to transmit to STA 2320. In an embodiment, STA 2330 may transition from HCM to LCM after receiving frame 2312. In an embodiment, this transition from HCM to LCM, for STA 2320, STA 2330, or both, may reduce unnecessary overhead and / or lower power consumption by allowing one or more of the STAs to transition to LCM when AP 2310 has no more buffered BUs to transmit to the STAs.

[0229] FIG. 24 illustrates an example 2400 according to an embodiment. As shown in FIG. 24, example 2400 includes an AP 2410, a STA 2420, and another STA 2430. In an example, STAs 2420 and 2430 areDocket No.: 24-3051 PCT associated with AP 2410. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2410 and STAs 2420 and 2430 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0230] As illustrated in example 2400, STAs 2420 and 2430 each begin in LCM. In an embodiment, AP 2410 may transmit a BSRP to STAs 2420 and 2430. STA 2420 receives the BSRP from AP 2410 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2420 may transmit a BSR 2422 to AP 2410, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2430 also receives the BSRP from AP 2410 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2430 may transmit a BSR 2432 to AP 2410, after transitioning to HCM, in response to receiving the BSRP.

[0231] In an embodiment, STA 2420 may indicate in BSR 2422 that STA 2420 has uplink data for transmission to AP 2410. Further, in an embodiment, STA 2430 may also indicate in BSR 2432 that STA 2430 has uplink data for transmission to AP 2410. AP 2410 may transmit a TF to STAs 2420 and 2430. STA 2420 may receive the TF, and may transmit a frame 2424 (e.g., an uplink data frame) to AP 2410. STA 2420 may also receive the TF, and may transmit a frame 2434 (e.g., an uplink data frame) to AP 2410.

[0232] In an embodiment, AP 2410 may receive frames 2424 and 2434 and may transmit a frame 2412 to both STA 2420 and STA 2430 (e.g., a M-BA frame with a RA field set to broadcast). In an embodiment, AP 2410 may indicate in frame 2412 whether AP 2410 has additional downlink data frames buffered (e.g., for STA 2420, STA 2430, or both).

[0233] For example, AP 2410 may set a MD subfield of frame 2412 to 1 to indicate when AP 2410 has at least one BU for at least one STA (e.g., at least one STA indicated in an AID TID Info subfield of an M-BA frame). As another example, AP 2410 may set a MD subfield of frame 2412 to 1 to indicate when AP 2410 has at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0234] As another example, AP 2410 may set a MD subfield of frame 2412 to 0 to indicate when AP 2410 does not have at least one BU for at least one STA (e.g., at least one STA indicated in an AID TID Info subfield of an M-BA frame). As a further example, AP 2410 may set a MD subfield of frame 2412 to 0 to indicate when AP 2410 does not have at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0235] In an embodiment, a STA receiving a response frame (e.g., a M-BA with a RA set to broadcast) from an AP with a MD subfield set to 0 may transition to LCM. Otherwise, if a MD subfield is set to 1 , a STA receiving the response frame will maintain HCM. Further, in an embodiment, a response frame (e.g., a M- BA) may include a field indicating whether a MD subfield is valid. In this embodiment, a STA receiving a response frame will only use the MD subfield to determine whether to transition from HCM to LCM if the MD valid field is set. Alternatively, where a response frame does not include a MD valid field, a receiving STA may always use the MD subfield to determine whether to transition from HCM to LCM.Docket No.: 24-3051 PCT

[0236] In an embodiment, AP 2410 sets a MD subfield to 1 in frame 2412. STA 2420 may receive frame 2412, indicating that AP 2410 has more BUs to transmit to STA 2420. In an embodiment, STA 2420 may remain in HCM after receiving frame 2412. Further, in an embodiment, STA 2430 may also receive frame 2412, and frame 2412 may indicate that AP 2410 also has BUs to transmit to STA 2420. In an embodiment, STA 2430 may also remain in HCM after receiving frame 2412. In an embodiment, remaining in HCM, for STA 2420, STA 2430, or both, may reduce unnecessary overhead by allowing one or more of the STAs to remain in HCM when AP 2410 has additional BUs to transmit to the STAs.

[0237] FIG. 25 illustrates an example 2500 according to an embodiment. As shown in FIG. 25, example 2500 includes an AP 2510, a STA 2520, and another STA 2530. In an example, STAs 2520 and 2530 are associated with AP 2510. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2510 and STAs 2520 and 2530 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0238] As illustrated in example 2500, STAs 2520 and 2530 each begin in LCM. In an embodiment, AP 2510 may transmit a BSRP to STAs 2520 and 2530. STA 2520 receives the BSRP from AP 2510 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2520 may transmit a BSR 2522 to AP 2510, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2530 also receives the BSRP from AP 2510 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2530 may transmit a BSR 2532 to AP 2510, after transitioning to HCM, in response to receiving the BSRP.

[0239] In an embodiment, STA 2520 may indicate in BSR 2522 that STA 2520 has uplink data for transmission to AP 2510. Further, in an embodiment, STA 2530 may also indicate in BSR 2532 that STA 2530 has uplink data for transmission to AP 2510. AP 2510 may transmit a TF to STAs 2520 and 2530. STA 2520 may receive the TF, and may transmit a frame 2524 (e.g., an uplink data frame) to AP 2510. STA 2520 may also receive the TF, and may transmit a frame 2534 (e.g., an uplink data frame) to AP 2510.

[0240] In an embodiment, AP 2510 may receive frames 2524 and 2534 and may transmit a frame 2512 to both STA 2520 and STA 2530 (e.g., a M-BA frame with a RA field set to broadcast). In an embodiment, AP 2510 may indicate in frame 2512 whether AP 2510 has additional downlink data frames buffered (e.g., for STA 2520, STA 2530, or both).

[0241] For example, AP 2510 may set a MD subfield of frame 2512 to 1 to indicate when AP 2510 has at least one BU for at least one STA (e.g., at least one STA indicated in an AID TID Info subfield of an M-BA frame). As another example, AP 2510 may set a MD subfield of frame 2512 to 1 to indicate when AP 2510 has at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0242] As another example, AP 2510 may set a MD subfield of frame 2512 to 0 to indicate when AP 2510 does not have at least one BU for at least one STA (e.g., at least one STA indicated in an AID TID Info subfield of an M-BA frame). As a further example, AP 2510 may set a MD subfield of frame 2512 to 0 toDocket No.: 24-3051 PCT indicate when AP 2510 does not have at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0243] In an embodiment, a STA receiving a response frame (e.g., a M-BA with a RA set to broadcast) from an AP with a MD subfield set to 0 may transition to LCM. Otherwise, if a MD subfield is set to 1 , a STA receiving the response frame will maintain HOM. Further, in an embodiment, a response frame (e.g., a M- BA) may include a field indicating whether a MD subfield is valid. In this embodiment, a STA receiving a response frame will only use the MD subfield to determine whether to transition from HCM to LCM if the MD valid field is set. Alternatively, where a response frame does not include a MD valid field, a receiving STA may always use the MD subfield to determine whether to transition from HCM to LCM.

[0244] In an embodiment, AP 2510 sets a MD subfield to 1 in frame 2512. STA 2520 may receive frame 2512, indicating that AP 2510 has more BUs to transmit to STA 2520. In an embodiment, STA 2520 may remain in HCM after receiving frame 2512. Further, in an embodiment, STA 2530 may also receive frame 2512, and frame 2512 may indicate that AP 2510 also has BUs to transmit to STA 2520. In an embodiment, STA 2530 may also remain in HCM after receiving frame 2512.

[0245] In an embodiment, AP 2510 may not transmit any data frames to STA 2520 immediately after transmitting frame 2512 (e.g., AP 2510 may not immediately obtain a TXOP), while STA 2520 and STA 2530 are in HCM. In an embodiment, STA 2520 and STA 2530 may each remain in HCM for a first period after receiving frame 2512, waiting to receive an additional frame from AP 2510, and then may transition to LCM (e.g., after a STT) after the first period expires. For example, the first period may be a duration in which STA 2520 and STA 2530 remain in HCM and wait for an additional frame, after STA 2520 and STA 2530 have received or transmitted their respective last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an IGF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0246] In an embodiment, STA 2520 and STA 2530 may each transition from HCM to LCM if they do not receive any frames from AP 2510 during the first period. Alternatively, STA 2520 and STA 2530 may each transition from HCM to LCM if they do not receive a frame addressed to the recipient, or indicating / allocating the recipient, during the first period. For example, STA 2520 may transition from HCM to LCM if it does not receive a frame addressed to STA 2520 from AP 2510 during the first period. As another example, STA 2530 may transition from HCM to LCM if it does not receive a frame addressed to STA 2530 from AP 2510 during the first period.

[0247] As illustrated, AP 2510 transmits frame 2514, to STA 2520, during the first period. STA 2520 has remained in HCM, and so, in an embodiment, STA 2520 receives frame 2514 from AP 2510 and may transmit a BA 2526 to AP 2510.Docket No.: 24-3051 PCT

[0248] Further, in an embodiment, STA 2530 may receive frame 2514, during the first period, and identify frame 2514 as intended for STA 2520 (and not STA 2530). In an embodiment, STA 2530 may transition from HCM to LCM, during the first period, when STA 2530 receives a frame from AP 2510 addressed to another STA (e.g., other than STA 2530).

[0249] Alternatively, in an embodiment, STA 2530 may use a TXOP duration and / or PPDU duration indicated in frame 2514 to determine whether to transition from HCM to LCM during the first period. For example, STA 2530 may receive frame 2514 and determine that frame 2514 is intended for STA 2520. But, in an embodiment, STA 2530 may transition from HCM to LCM during the first period only if STA 2530 determines that the TXOP duration and / or PPDU duration indicated in frame 2514 exceeds the first period. Thus, in an embodiment, STA 2530 may transition from HCM to LCM when STA 2530 both receives a frame from AP 2510 addressed to another STA (e.g., other than STA 2530), and determines that the TXOP duration and / or PPDU duration indicated in frame 2514 exceeds the first period As illustrated, STA 2530 determines that the TXOP and / or PPDU duration indicated in frame 2514 exceeds the first period, and so STA 2530 transitions from HCM to LCM (e.g., after a STT). In an embodiment, one or more of the transitions from HCM to LCM illustrated in example 2500 may reduce unnecessary overhead and / or lower power consumption by allowing STA 2520 and / or STA 2530 to transition from HCM to LCM efficiently, while also receiving data frames efficiently.

[0250] FIG. 26 illustrates an example 2600 according to an embodiment. As shown in FIG. 26, example 2600 includes an AP 2610, a STA 2620, and another STA 2630. In an example, STAs 2620 and 2630 are associated with AP 2610. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2610 and STAs 2620 and 2630 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0251] As illustrated in example 2600, STAs 2620 and 2630 each begin in LCM. In an embodiment, AP 2610 may transmit a BSRP to STAs 2620 and 2630. STA 2620 receives the BSRP from AP 2610 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2620 may transmit a BSR 2622 to AP 2610, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2630 also receives the BSRP from AP 2610 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2630 may transmit a BSR 2632 to AP 2610, after transitioning to HCM, in response to receiving the BSRP.

[0252] In an embodiment, STA 2620 may indicate in BSR 2622 that STA 2620 has uplink data for transmission to AP 2610. Further, in an embodiment, STA 2630 may also indicate in BSR 2632 that STA 2630 has uplink data for transmission to AP 2610. AP 2610 may transmit a TF to STAs 2620 and 2630. STA 2620 may receive the TF, and may transmit a frame 2624 (e.g., an uplink data frame) to AP 2610. STA 2620 may also receive the TF, and may transmit a frame 2634 (e.g., an uplink data frame) to AP 2610.Docket No.: 24-3051 PCT

[0253] In an embodiment, AP 2610 may receive frames 2624 and 2634 and may transmit a frame 2612 to both STA 2620 and STA 2630 (e.g., a M-BA frame with a RA field set to broadcast). In an embodiment, AP 2610 may indicate in frame 2612 whether AP 2610 has additional downlink data frames buffered (e.g., for STA 2620, STA 2630, or both).

[0254] For example, AP 2610 may set a MD subfield of frame 2612 to 0 to indicate when AP 2610 does not have at least one BU for at least one STA (e.g., at least one STA indicated in an AID TID Info subfield of an M-BA frame). As a further example, AP 2610 may set a MD subfield of frame 2612 to 0 to indicate when AP 2610 does not have at least one BU for all STAs (e.g., all STAs indicated in an AID TID Info subfield of an M-BA frame).

[0255] In an embodiment, STAs 2620 and 2630 may receive frame 2612 from AP 2610, and may remain in HCM for a first period (e.g., even though frame 2612 indicates that AP 2610 has no additional downlink data frames buffered, or regardless of whether frame 2612 indicates that AP 2610 has additional downlink data frames buffered). For example, STA 2620 and STA 2630 may each remain in HCM for a first period after receiving frame 2612 with a MD subfield set to 0, waiting to receive an additional frame from AP 2610, and then may transition to LCM (e.g., after a STT) after the first period expires.

[0256] In an embodiment, the first period may be a duration in which STA 2620 and STA 2630 remain in HCM and wait for an additional frame, after STA 2620 and STA 2630 have received or transmitted their respective last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an ICF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0257] In an embodiment, STA 2620 and STA 2630 may each transition from HCM to LCM if they do not receive any frames from AP 2610 during the first period. Alternatively, STA 2620 and STA 2630 may each transition from HCM to LCM if they do not receive a frame addressed to the recipient, or indicating / allocating the recipient, during the first period. For example, STA 2620 may transition from HCM to LCM if it does not receive a frame addressed to STA 2620 from AP 2610 during the first period. As another example, STA 2630 may transition from HCM to LCM if it does not receive a frame addressed to STA 2630 from AP 2610 during the first period.

[0258] As illustrated, AP 2610 transmits frame 2614, to STA 2620, during the first period STA 2620 has remained in HCM, and so, in an embodiment, STA 2620 receives frame 2614 from AP 2610 and may transmit a BA 2626 to AP 2610.

[0259] Further, in an embodiment, STA 2630 may receive frame 2614, during the first period, and identify frame 2614 as intended for STA 2620 (and not STA 2630). In an embodiment, STA 2630 may transition fromDocket No.: 24-3051 PCTHCM to LCM, during the first period, when STA 2630 receives a frame from AP 2610 addressed to another STA (e.g., other than STA 2630).

[0260] Alternatively, in an embodiment, STA 2630 may use a TXOP duration and / or PPDU duration indicated in frame 2614 to determine whether to transition from HCM to LCM during the first period. For example, STA 2630 may receive frame 2614 and determine that frame 2614 is intended for STA 2620. But, in an embodiment, STA 2630 may transition from HCM to LCM during the first period only if STA 2630 determines that the TXOP duration and / or PPDU duration indicated in frame 2614 exceeds the first period. Thus, in an embodiment, STA 2630 may transition from HCM to LCM when STA 2630 both receives a frame from AP 2610 addressed to another STA (e.g., other than STA 2630), and determines that the TXOP duration and / or PPDU duration indicated in frame 2614 exceeds the first period. As illustrated, STA 2630 determines that the TXOP and / or PPDU duration indicated in frame 2614 exceeds the first period, and so STA 2630 transitions from HCM to LCM (e.g., after a STT). In an embodiment, one or more of the transitions from HCM to LCM illustrated in example 2600 may reduce unnecessary overhead and / or lower power consumption by allowing STA 2620 and / or STA 2630 to transition from HCM to LCM efficiently, while also receiving data frames efficiently.

[0261] FIG. 27 illustrates an example 2700 according to an embodiment. As shown in FIG. 27, example 2700 includes an AP 2710, a STA 2720, and another STA 2730. In an example, STAs 2720 and 2730 are associated with AP 2710. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2710 and STAs 2720 and 2730 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0262] As illustrated in example 2700, STAs 2720 and 2730 each begin in LCM. In an embodiment, AP 2710 may transmit a BSRP to STAs 2720 and 2730. STA 2720 receives the BSRP from AP 2710 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2720 may transmit a BSR 2722 to AP 2710, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2730 also receives the BSRP from AP 2710 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2730 may transmit a BSR 2732 to AP 2710, after transitioning to HCM, in response to receiving the BSRP.

[0263] In an embodiment, STA 2720 may indicate in BSR 2722 that STA 2720 has uplink data for transmission to AP 2710. Further, in an embodiment, STA 2730 may also indicate in BSR 2732 that STA 2730 has uplink data for transmission to AP 2710. AP 2710 may transmit a TF to STAs 2720 and 2730. STA 2720 may receive the TF, and may transmit a frame 2724 (e.g., an uplink data frame) to AP 2710. STA 2720 may also receive the TF, and may transmit a frame 2734 (e.g., an uplink data frame) to AP 2710.

[0264] In an embodiment, AP 2710 may receive frames 2724 and 2734 and may transmit a frame 2712 to both STA 2720 and STA 2730 (e.g., a M-BA frame with a RA field set to broadcast). In an embodiment, APDocket No.: 24-3051 PCT2710 may indicate in frame 2712 whether AP 2710 has additional downlink data frames buffered (e.g., for STA 2720, STA 2730, or both).

[0265] In an embodiment, AP 2710 may include in frame 2712 a traffic indication describing which recipient STAs have buffered traffic (e.g., buffered BUs) at AP 2710. For example, frame 2712 may be a M-BA transmitted by AP 2710 to STAs 2720 and 2730. In an embodiment, frame 2712 may include a STA-ID (e.g., 1 1 bits per STA) list for STAs for which AP 2710 has buffered traffic (e.g., a 44 bit list for four STAs). The STA-ID list may be fixed size, or a variable size. In an embodiment, frame 2712 may include a length indication for a variable size STA-ID list. Alternatively, frame 2712 may include a STA indication bitmap field identifying STAs for which AP 2710 has buffered traffic. For example, a STA indication bitmap field may be variable in length, and each bit can correspond to each STA indicated in a User Info field. The STA indication bitmap field may be significantly smaller than a STA-ID list. As a third alternative, frame 2712 may include a group identifier. In an embodiment, the group identifier may be associated with each STA and may have been assigned previously to each STA. In an embodiment, a MD subfield in frame 2712 can be used to indicate that a traffic indication for each STA may be included in frame 2712 (e.g., a MD subfield set to 1 may indicate that a traffic indication for each STA is included).

[0266] In an embodiment, as an alternative to a traffic indication, AP 2710 may include in frame 2712 a power state transition allowance. For example, AP 2710 may include in frame 2712 an indication of whether all recipient STAs are allowed to transition from HCM to LCM (e.g., if the indication is yes, all STAs indicated in frame 2712 are allowed to transition from HCM to LCM). As another example, AP 2710 may include a STA-ID list for STAs which are allowed to transition to LCM. As described above for the traffic indication, the STA-ID list may be fixed in size or variable in size (e.g., frame 2712 may include an indication of the size of the STA-ID list). As a further example, AP 2710 may include a STA indication bitmap field for STAs which are allowed to transition to LCM (e.g., as described above for the traffic indication), or may include a group ID for STAs which are allowed to transition to LCM. In an embodiment, AP 2710 may allow a given STA to transition to LCM if AP 2710 does not have buffered BUs for the STA, and may not allow a given STA to transition to LCM if AP has buffered BUs for the STA. In an embodiment, a STA receiving frame 2712 may transition from HCM to LCM if the power state transition allowance indicates the STA is allowed to transition. Otherwise, the STA may maintain HCM.

[0267] As illustrated, frame 2712 includes a traffic indication identifying buffered data (e.g., one or more buffered BUs) for STA 2720 and no buffered data (e.g., no buffered BUs) for STA 2730. STA 2720 receives frame 2712 and remains in HCM. AP 2710 transmits frame 2714 (e.g., a downlink data frame) to STA 2720, while STA 2720 remains in HCM, and STA 2720 responds by transmitting BA 2726 to AP 2710. STA 2720 also receives frame 2712 and transitions from HCM to LCM, after a STT, based on the traffic indication in frame 2712 identifying no buffered data for STA 2730. In an embodiment, one or more of the transitions from HCM to LCM illustrated in example 2700 may reduce unnecessary overhead and / or lower powerDocket No.: 24-3051 PCT consumption by allowing STA 2720 and / or STA 2730 to transition from HCM to LCM efficiently, while also receiving data frames efficiently.

[0268] FIG. 28 illustrates an example 2800 according to an embodiment. As shown in FIG. 28, example 2800 includes an AP 2810, a STA 2820, a STA 2830, and another STA 2840. In an example, STAs 2820, 2830, and 2840 are associated with AP 2810. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2810 and STAs 2820, 2830, and 2840 support a DPS mode in which a STA may operate using a LCM or a HCM.

[0269] As illustrated in example 2800, STAs 2820 and 2830 each begin in LCM. In an embodiment, AP 2810 may transmit a BSRP to STAs 2820 and 2830. STA 2820 receives the BSRP from AP 2810 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2820 may transmit a BSR 2822 to AP 2810, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2830 also receives the BSRP from AP 2810 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2830 may transmit a BSR 2832 to AP 2810, after transitioning to HCM, in response to receiving the BSRP.

[0270] In an embodiment, after transmitting to an AP, or receiving from an AP, a frame not soliciting an immediate response, a STA may remain in HCM for a first period and then transition to LCM after the first period expires. For example, after transmitting BSR 2822 to AP 2810, STA 2820 may remain in HCM for the first period and then transition to LCM (e.g., after a STT) after the first period expires. Similarly, after transmitting BSR 2832 to AP 2810, STA 2830 may remain in HCM for the first period and then transition to LCM (e.g., after a STT) after the first period expires. A BSR is merely one example of a frame not soliciting an immediate response, and, in an embodiment, a STA may remain in HCM for a first period and then transition to LCM, after transmitting, or receiving, any suitable frame not soliciting an immediate response.

[0271] In an embodiment, the first period may be a duration in which STA 2820 and STA 2830 remain in HCM and wait for an additional frame, after STA 2820 and STA 2830 have received or transmitted their respective last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an ICF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0272] In an embodiment, STA 2820 and STA 2830 may each transition from HCM to LCM if they do not receive any frames from AP 2810 during the first period. Alternatively, STA 2820 and STA 2830 may each transition from HCM to LCM if they do not receive a frame addressed to the recipient, or indicating / allocating the recipient, during the first period. For example, STA 2820 may transition from HCM to LCM if it does not receive a frame addressed to STA 2820 from AP 2810 during the first period. As another example, STA 2830 may transition from HCM to LCM if it does not receive a frame addressed to STA 2830 from AP 2810 duringDocket No.: 24-3051 PCT the first period. As another example, STA 2830 may transition from HCM to LCM if STA 2830 does not receive any frame from AP 2810 during the first period.

[0273] As illustrated, AP 2810 transmits frame 2812 (e.g., a downlink data frame) to STA 2840, during the first period. STA 2820 and STA 2830 may each receive frame 2812 and identify frame 2812 as intended for STA 2840 (not STA 2820 or STA 2830). In an embodiment, STAs 2820 and 2830 may each transition from HCM to LCM, during the first period, when each STA receives a frame from AP 2810 addressed to another STA (e.g., STA 2840). As illustrated, STA 2840 receives frame 2812 and transmits a BA 2842, to AP 2810, in response.

[0274] Alternatively, in an embodiment, STA 2830 may use a TXOP duration and / or PPDU duration indicated in frame 2812 to determine whether to transition from HCM to LCM during the first period. For example, STAs 2820 and 2830 may each receive frame 2812 and determine that frame 2812 is intended for STA 2840 But, in an embodiment, STAs 2820 and 2830 may transition from HCM to LCM during the first period only if STAs 2820 and 2830 determine that the TXOP duration and / or PPDU duration indicated in frame 2812 exceeds the first period. Thus, in an embodiment, STAs 2820 and 2830 may transition from HCM to LCM when STAs 2820 and 2830 both receive a frame from AP 2810 addressed to another STA (e.g., STA 2840), and determine that the TXOP duration and / or PPDU duration indicated in frame 2812 exceeds the first period. As illustrated, STAs 2820 and 2830 determine that the TXOP and / or PPDU duration indicated in frame 2812 exceeds the first period, and so STAs 2820 and 2830 transition from HCM to LCM (e.g., after a STT).

[0275] In an embodiment, AP 2810 transmits TF 2814 to STAs 2820, 2830, and 2840, after receiving BA 2842 from STA 2840. STA 2820 receives TF 2814 and transitions from LCM to HCM (e.g., after a STT). After transitioning to HCM, STA 2820 transmits a frame 2824 (e.g., an uplink data frame) to AP 2810. STA 2830 also receives TF 2814 and transitions from LCM to HCM (e.g., after a STT). After transitioning to HCM, STA 2830 transmits a frame 2834 (e.g., an uplink data frame) to AP 2810. As illustrated, AP 2810 transmits a frame 2816 (e.g., a M-BA) to STAs 2820 and 2830, after receiving frames 2824 and 2834. In an embodiment, one or more of the transitions from HCM to LCM illustrated in example 2800 may reduce unnecessary overhead and / or lower power consumption by allowing STA 2820 and / or STA 2830 to transition from HCM to LCM efficiently, while also receiving data frames efficiently.

[0276] FIG. 29 illustrates an example 2900 according to an embodiment. As shown in FIG. 29, example 2900 includes an AP 2910, a STA 2920, and another STA 2930. In an example, STAs 2920 and 2930are associated with AP 2910. Further, like AP 1210 and STA 1220 illustrated in example 1200 in FIG. 12, in an embodiment AP 2910 and STAs 2920 and 2930support a DPS mode in which a STA may operate using a LCM or a HCM.

[0277] As illustrated in example 2900, STAs 2920 and 2930 each begin in LCM. In an embodiment, AP 2910 may transmit a BSRP to STAs 2920 and 2930. STA 2920 receives the BSRP from AP 2910 (e.g., atDocket No.: 24-3051 PCT least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2920 may transmit a BSR 2922 to AR 2910, after transitioning to HCM, in response to receiving the BSRP. Similarly, STA 2930 also receives the BSRP from AP 2910 (e.g., at least a portion of the BSRP), and may transition from LCM to HCM after a STT. STA 2930 may transmit a BSR 2932 to AP 2910, after transitioning to HCM, in response to receiving the BSRP.

[0278] In an embodiment, after transmitting to an AP, or receiving from an AP, a frame not soliciting an immediate response, a STA may remain in HCM for a first period and then transition to LCM after the first period expires. For example, after transmitting BSR 2922 to AP 2910, STA 2920 may remain in HCM for the first period and then transition to LCM (e.g., after a STT) after the first period expires. Similarly, after transmitting BSR 2932 to AP 2910, STA 2930 may remain in HCM for the first period and then transition to LCM (e.g., after a STT) after the first period expires. A BSR is merely one example of a frame not soliciting an immediate response, and, in an embodiment, a STA may remain in HCM for a first period and then transition to LCM, after transmitting, or receiving, any suitable frame not soliciting an immediate response.

[0279] In an embodiment, the first period may be a duration in which STA 2920 and STA 2930 remain in HCM and wait for an additional frame, after STA 2920 and STA 2930 have received or transmitted their respective last frame. As discussed above in relation to example 1700 illustrated in FIG. 17, in an embodiment the first period may be provided by a STA to an AP or provided by an AP to a STA (e.g., as part of a negotiation between the STA and AP), or may be fixed (e.g., included in an IEEE standard document). Further, in an embodiment, an AP may not transmit an ICF (e.g., an RTS, MU-RTS, BSRP, BAR, etc.) to a STA during the first period.

[0280] In an embodiment, STA 2920 and STA 2930 may each transition from HCM to LCM if they do not receive any frames from AP 2910 during the first period. Alternatively, STA 2920 and STA 2930 may each transition from HCM to LCM if they do not receive a frame addressed to the recipient, or indicating / allocating the recipient, during the first period. For example, STA 2920 may transition from HCM to LCM if it does not receive a frame addressed to STA 2920 from AP 2910 during the first period. As another example, STA 2930 may transition from HCM to LCM if it does not receive a frame addressed to STA 2930 from AP 2910 during the first period.

[0281] As illustrated, AP 2910 transmits frame 2912 (e.g., a TF address to STAs 2920 and 2930) to STAs 2920 and 2930 during the first period. In an embodiment, STA 2920 receives frame 2912, addressed to STA 2920, within the first period, and may remain in HCM after the first period expires. STA 2930 receives frame 2912, addressed to STA 2930, within the first period, and also may remain in HCM after the first period expires.

[0282] In an embodiment STA 2920 may transmit a frame 2924 (e.g., an uplink data frame) to AP 2910. STA 2930 transmits a frame 2934 (e.g., an uplink data frame) to AP 2910. As illustrated, AP 2910 transmits a frame 2914 (e.g., a M-BA) to STAs 2920 and 2930, after receiving frames 2924 and 2934. In anDocket No.: 24-3051 PCT embodiment, one or more of the transitions from HCM to LCM illustrated in example 2900 may reduce unnecessary overhead and / or lower power consumption by allowing STA 2920 and / or STA 2930 to transition from HCM to LCM efficiently, while also receiving data frames efficiently.

[0283] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to implementations including more than one STA.

[0284] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to implementations including more than one AP.

[0285] As would be understood by a person of skill in the art based on the teachings herein, the embodiments as described by the above examples may be readily extended to scenarios in which any of the APs or any of the STAs may comprise a MLD, comprising at least one affiliated AP or affiliated STA.

[0286] FIG. 30 illustrates an example process 3000 according to an embodiment.

[0287] Example process 3000 may be performed by a suitable STA, such as STAs 1320, 1420, 1520, 1620, 1720, 1820, 1920, 2020, 2120, 2220, 2230, 2320, 2330, 2420, 2430, 2520, 2530, 2620, 2630, 2720, 2730, 2820, 2830, 2840, 2920, or 2930 illustrated in FIGS. 13-29, for example. As shown in FIG. 30, process 3000 may include step 3002.

[0288] Step 3002 includes transmitting, by a first station (STA) to an access point (AP) and while in a first power state of a power save mode, a first frame soliciting a second frame. In an embodiment the AP includes any suitable AP, including APs 1310, 1410, 1510, 1610, 1710, 1810, 1910, 2010, 2110, 2210, 2310, 2410, 2510, 2610, 2710, 2810, or 2910 illustrated in FIGS. 13-29, for example.

[0289] Step 3004 includes, in response to the first frame, receiving, by the first STA from the AP, the second frame. In an embodiment, the second frame indicates absence at the AP of a downlink (DL) buffered bufferable unit (BU) for the first STA.

[0290] Step 3006 includes, based on receiving the second frame, transitioning, by the first STA, from the first power state to a second power state of the power save mode.

[0291] In an embodiment, the power save mode comprises a dynamic power save mode.

[0292] In an embodiment, the first power state comprises a high power state, a high capability mode, a high power capability mode, or a high power capability state.

[0293] In an embodiment, while in the first power state the first STA is configured to transmit a frame using at least one of an operating bandwidth (BW), a number of spatial stream (NSS), and a modulation coding scheme (MCS) that is higher than in the second power state.

[0294] In an embodiment, the second power state comprises a low power state, a low capability mode, a low power capability mode, or a low power capability state.Docket No.: 24-3051 PCT

[0295] In an embodiment, while in the second power state the first STA is configured to transmit a frame using one or more of: a 20MHz bandwidth (BW), one spatial stream (SS), a limited / lower data rate compared with the first power state, a limited PPDU format set compared with the first power state, and a limited control frame set (e.g., comprising only ICF, MU-RTS, and BSRP) compared with the first power state.

[0296] In an embodiment, the first frame comprises a data frame, a quality of service (QoS) data frame, a management frame, a control frame, a QoS null frame, or an action frame.

[0297] In an embodiment, the second frame comprises at least one of an acknowledgement (Ack) frame, a blockack (BA) frame, a compressed BA frame, a multi-STA BA frame, another response frame, or a control frame.

[0298] In an embodiment, an address subfield of the second frame comprises an individual address ( / an unicast address) or a broadcast address.

[0299] In an embodiment, the address subfield of the second frame comprises a receiver address ( / Address 1).

[0300] In an embodiment, based on the address subfield comprising the broadcast address, the second frame indicates ( / allocates) one or more STAs.

[0301] In an embodiment, the second frame indicating the one or more STAs comprises the second frame comprising one or more per association identifier (AID) traffic identifier (TID) info subfields corresponding to each of the one or more STAs.

[0302] In an embodiment, the first frame soliciting the immediate response frame comprises an ack policy subfield indicating implicit BAR (00).

[0303] In an embodiment, the process 3000 further includes receiving, by the first STA from the AP and while the first STA is in the second power state, a third frame indicating ( / allocating) the first STA, and transitioning, by the first STA, from the second power state to the first power state of the power save mode.

[0304] In an embodiment, the third frame comprises at least one of: (I) a trigger frame, a basic Trigger frame, or an initial control frame, or (ii) a receiver address set to a media access control (MAC) address of the first STA.

[0305] In an embodiment, the third frame indicates a second STA, and the second frame indicates the second STA.

[0306] In an embodiment, the third frame comprises a broadcast receiver address.

[0307] In an embodiment, the second frame indicating the absence of the DL buffered BU at AP for the first STA comprises the second frame comprising a more data (MD) subfield, of a MAC header of the second frame, equal ( / set) to 0.

[0308] In an embodiment, the second frame indicates an allowance of transitioning, by the first STA, from the first power state to the second power state.Docket No.: 24-3051 PCT

[0309] In an embodiment, the indication of allowance comprises at least one of a STA-identifier(ID) list, a STA indication map bitmap, or a group ID.

[0310] In an embodiment, the STA-ID list comprises one or more STA IDs identifying: (i) one or more STAs for which the AP has buffered traffic, or (ii) one or more STAs that are allowed to transition to the second power state after the second frame.

[0311] In an embodiment, the STA indication bitmap comprises a bitmap identifying: (i) one or more STA for which the AP has buffered traffic, or (ii) one or more STAs that are allowed to transition to the second power state after the second frame.

[0312] In an embodiment, each bit of the STA indication bitmap corresponds to a respective STA indicated in a per AID TID info subfield of the second frame.

[0313] In an embodiment, the group ID comprises an identifier of a group corresponding to: (i) one or more STAs for which the AP has buffered traffic, or (ii) one or more STAs that are allowed to transition to second power state after the second frame.

[0314] In an embodiment, the second frame further comprises a subfield indicating whether a more data subfield of the MAC header of the second frame is valid.

[0315] In an embodiment, the process 3000 further includes, in response to a fourth frame, receiving, by the first STA from the AP, a fifth frame indicating presence at the AP of at least one DL buffered BU for the first STA, and based on receiving the fifth frame, maintaining( / retaining / keeping), by the first STA, the first power state.

[0316] In an embodiment, the fifth frame indicating the presence of the at least one DL buffered BU at AP for the first STA comprises the fifth frame comprising a MD subfield, of a MAC header of the fifth frame, equal ( / set) to 1.

[0317] In an embodiment, the fifth frame indicates disallowance of transitioning, the first STA, from the first power state to the second power state.

[0318] In an embodiment, the fifth frame indicating the disallowance comprises the AP not having buffered traffic for the first STA.

[0319] In an embodiment, the indicating the disallowance comprises the fifth frame comprising at least one of a STA-ID list, a STA indication bitmap, or a group ID.

[0320] In an embodiment, the process 3000 further includes transitioning, by the first STA, to the second power state based on a first condition.

[0321] In an embodiment, the first condition comprises at least one of: not receiving any frame from the AP during a first time period after receiving the fifth frame indicating the presence at the AP of the at least one DL buffered BU, receiving a frame that is addressed to another STA, from the AP, during the first time period, or receiving a frame that is not addressed to the first STA from the AP during the first time period.Docket No.: 24-3051 PCT

[0322] In an embodiment, the process 3000 further includes transmitting, by the first STA to the AP, a sixth frame indicating the first time period.

[0323] In an embodiment, the sixth frame comprises a probe request frame, an association request frame, an individually addressed management frame, a control frame, a QoS data / null frame, or an action frame.

[0324] In an embodiment, the process 3000 further includes receiving, by the first STA from the AP, a seventh frame indicating the first time period.

[0325] In an embodiment, the seventh frame comprises a probe response frame, an association response frame, an individually addressed( / group addressed) management frame, a control frame, a QoS data / null frame, or an individually addressed( / group addressed) action frame.

[0326] In an embodiment, the first time period has a fixed value.

[0327] In an embodiment, the first time period is pre-configured (e.g., fixed in an IEEE 802.11 standard).

[0328] In an embodiment, the AP does not transmit an initial control frame to the first STA during the first time period.

[0329] In an embodiment, the process 3000 further includes receiving, by the first STA from the AP, a buffer status report poll (BSRP) trigger frame indicating / allocating the first STA, transmitting, by the first STA to the AP, a BSR frame, and after transmitting the BSR frame, transitioning, by the first STA, to the second power state based on the first condition.

[0330] In an embodiment, the process 3000 further includes maintaining, by the first STA, the first power state based on receiving an eighth frame within the first time period.

[0331] In an embodiment, wherein the eighth frame comprises a frame that is addressed to the first STA.

[0332] FIG. 31 illustrates an example process 3100 according to an embodiment.

[0333] Example process 3100 may be performed by a suitable STA, such as STAs 1320, 1420, 1520, 1620, 1720, 1820, 1920, 2020, 2120, 2220, 2230, 2320, 2330, 2420, 2430, 2520, 2530, 2620, 2630, 2720, 2730, 2820, 2830, 2840, 2920, or 2930 illustrated in FIGS. 13-29, for example. As shown in FIG. 31 , process 3100 may include step 3102.

[0334] Step 3102 includes transmitting, by a station (STA) to an access point (AP) and while in a high capability mode of a power save mode, a first frame not soliciting a second frame. In an embodiment the AP includes any suitable AP, including APs 1310, 1410, 1510, 1610, 1710, 1810, 1910, 2010, 2110, 2210, 2310, 2410, 2510, 2610, 2710, 2810, or 2910 illustrated in FIGS. 13-29, for example.

[0335] Step 3104 includes, based on a first condition, transitioning, by the STA, from the high capability mode to a low capability mode of the power save mode.

[0336] In an embodiment, the first frame comprises a buffer status report (BSR) frame, an Ack frame, a blockack (BA) frame, a control frame, a management frame, a QoS data frame, a QoS null frame, or an action frame.Docket No.: 24-3051 PCT

[0337] In an embodiment, the first condition comprises one of: receiving, by the STA from the AP and during a first time period, a third frame that is not addressed to (is not indicating) the STA; or not receiving, by the STA from the AP and during the first time period, any frame

[0338] In an embodiment, the process 3100 further includes transmitting, by the first STA to the AP, a fourth frame indicating the first time period.

[0339] In an embodiment, the fourth frame comprises a probe request frame, an association request frame, an individually addressed management frame, a control frame, a QoS data / null frame, or an action frame.

[0340] In an embodiment, the process 3100 further includes receiving, by the first STA from the AP, a fifth frame indicating the first time period.

[0341] In an embodiment, the fifth frame comprises a probe response frame, an association response frame, an individually addressed( / group addressed) management frame, a control frame, a QoS data / null frame, or an individually addressed( / group addressed) action frame.

[0342] In an embodiment, the first time period has a fixed value.

[0343] In an embodiment, the first time period is pre-configured (e.g., fixed in an IEEE 802.11 standard).

[0344] In an embodiment, the AP does not transmit an initial control frame to the first STA during the first time period.

[0345] In an embodiment, the third frame is addressed to another STA.

[0346] In an embodiment, the first time period starts after transmitting the first frame.

[0347] In an embodiment, the second frame comprises an immediate response frame.

[0348] FIG. 32 illustrates an example process 3200 according to an embodiment.

[0349] Example process 3200 may be performed by a suitable STA, such as STAs 1320, 1420, 1520, 1620, 1720, 1820, 1920, 2020, 2120, 2220, 2230, 2320, 2330, 2420, 2430, 2520, 2530, 2620, 2630, 2720, 2730, 2820, 2830, 2840, 2920, or 2930 illustrated in FIGS. 13-29, for example. As shown in FIG. 32, process 3200 may include step 3202.

[0350] Step 3202 includes receiving, by a station (STA) from an access point (AP) and while in a high capability mode of a power save mode, a first frame not soliciting a second frame. In an embodiment the AP includes any suitable AP, including APs 1310, 1410, 1510, 1610, 1710, 1810, 1910, 2010, 2110, 2210, 2310, 2410, 2510, 2610, 2710, 2810, or 2910 illustrated in FIGS. 13-29, for example.

[0351] Step 3204 includes, based on a first condition, transitioning, by the STA, from the high capability mode to a low capability mode of the power save mode

[0352] In an embodiment, the first frame comprises an Ack frame, a blockack (BA) frame, a multi-STA BA frame, a control frame, a management frame, a QoS data frame, a QoS null frame, or an action frame.

[0353] In an embodiment, the first condition comprises one of: receiving, by the STA from the AP and during a first time period, a third frame that is not addressed to (is not indicating) the STA (is addressed to or other STA), or not receiving, by the STA from the AP and during the first time period, any frame.Docket No.: 24-3051 PCT

[0354] In an embodiment, the third frame is a frame not addressed to (not indicating) the STA or a frame addressed to another STA.

[0355] In an embodiment, the first time period starts after receiving the first frame.

[0356] In an embodiment, the second frame comprises an immediate response frame.

[0357] FIG. 33 illustrates an example process 3300 according to an embodiment.

[0358] Example process 3300 may be performed by a suitable STA, such as STAs 1320, 1420, 1520, 1620, 1720, 1820, 1920, 2020, 2120, 2220, 2230, 2320, 2330, 2420, 2430, 2520, 2530, 2620, 2630, 2720, 2730, 2820, 2830, 2840, 2920, or 2930 illustrated in FIGS. 13-29, for example. As shown in FIG. 33, process 3300 may include step 3302.

[0359] Step 3302 includes receiving, by a station (STA) from an access point (AP) and while in a high capability mode of a power save mode, a first frame: soliciting a second frame, and indicating absence at the AP of a buffered bufferable unit (BU) for the STA. In an embodiment the AP includes any suitable AP, including APs 1310, 1410, 1510, 1610, 1710, 1810, 1910, 2010, 21 10, 2210, 2310, 2410, 2510, 2610, 2710, 2810, or 2910 illustrated in FIGS. 13-29, for example.

[0360] Step 3304 includes transmitting, by the STA to the AP, the second frame.

[0361] Step 3306 includes, based on the first frame indicating the absence at the AP of the buffered BU for the STA and after transmitting the second frame, transitioning, by the STA, from the high capability mode to a low capability mode of the power save mode.

[0362] In an embodiment, the first frame comprises a downlink (DL) frame, a control frame, a management frame, a QoS data frame, a QoS null frame, an Ack frame, a blockack (BA) frame, a multi-STA BA frame, or an action frame.

[0363] In an embodiment, the second frame comprises an immediate response frame (e.g., an Ack or BA).

[0364] In an embodiment, the first frame soliciting the second frame comprises the first frame having an Ack policy subfield equal to implicit BAR (00) or HETP Ack (01 ).

[0365] In an embodiment, the process 3300 further includes receiving, by the STA from the AP, a third frame soliciting a fourth frame and indicating a presence at the AP of at least one buffered BU for the STA, transmitting, by the STA to the AP, the fourth frame, and based on the third frame indicating the presence at the AP of at least one buffered BU for the STA and after transmitting the fourth frame, maintaining ( / retaining / keeping), by the STA, the high capability mode.

[0366] In an embodiment, the process 3300 further includes receiving, by the STA from the AP, a fifth frame not soliciting a sixth frame and indicating an absence at the AP of buffered BU for the STA, and based on the fifth frame indicating the absence at the AP of buffered BUs for the STA and after receiving the fifth frame, transitioning, by the STA, from the high capability mode to the low capability mode.

[0367] In an embodiment, the process 3300 further includes receiving, by the STA from the AP, a seventh frame not soliciting an eighth frame and indicating a presence at the AP of buffered BUs for the STA, andDocket No.: 24-3051 PCT based on the seventh frame indicating the presence at the AP of the buffered BUs for the STA and after receiving the seventh frame, maintaining ( / retaining / keeping) , by the STA, the high capability mode.

[0368] In an embodiment, the not soliciting the eighth frame comprises the seventh frame having an Ack policy subfield equal to no Ack (10) or BA (11 ).

[0369] FIG. 34 illustrates an example process 3400 according to an embodiment.

[0370] Example process 3400 may be performed by a suitable STA, such as STAs 1320, 1420, 1520, 1620, 1720, 1820, 1920, 2020, 2120, 2220, 2230, 2320, 2330, 2420, 2430, 2520, 2530, 2620, 2630, 2720, 2730, 2820, 2830, 2840, 2920, or 2930 illustrated in FIGS. 13-29, for example. As shown in FIG. 34, process 3400 may include step 3402.

[0371] Step 3402 includes receiving, by a first station (STA) from an access point (AP) and while in a first power state of a power save mode, a first frame indicating absence at the AP of a downlink (DL) buffered bufferable unit (BU) for the first STA. In an embodiment the AP includes any suitable AP, including APs 1310, 1410, 1510, 1610, 1710, 1810, 1910, 2010, 2110, 2210, 2310, 2410, 2510, 2610, 2710, 2810, or 2910 illustrated in FIGS. 13-29, for example.

[0372] Step 3404 includes, based on receiving the first frame, transitioning, by the STA, from the first power state to a second power state (low capability mode) of the power save mode.

[0373] In an embodiment, a STA (e.g., an AP and / or a non-AP STA) as described above with reference to FIGS. 13-34 may further perform one or more of the operations described below. Specifically, as discussed above, an AP (e.g., AP 1310, AP 1410, AP 1510, AP 1610, AP 1710, AP 1810, AP 1910, AP 2010, AP 21 10, AP 2210, AP 2310, AP 2410, AP 2510, AP 2610, AP 2710, AP 2810, and / or AP 2910) or another STA (e.g., STA 1320, STA 1420, STA 1520, STA 1620, STA 1720, STA 1820, STA 1920, STA 2020, STA 2120, STA 2220, STA 2230, STA 2320, STA 2330, STA 2420, STA 2430, STA 2520, STA 2530, STA 2620, STA 2630, STA 2720, STA 2730, STA 2820, STA 2830, STA 2840, STA 2920, and / or STA 2930) may perform a procedure relating to a DPS operation as described below.

[0374] DPS operation may allow a DPS STA (e.g., a STA that enables its DPS mode), to operate with lower capabilities to reduce power consumption when listening on the link. The set of capabilities reduced by DPS operation may include the bandwidth, NSS, MCS, and the PPDU formats. A DPS STA may transition to its HC mode upon receiving an appropriate ICF, as described below, from a DPS assisting STA.

[0375] A non-AP UHR STA that has dotH UHRDPSAssistinglmplemented equal to 1 is called a DPS assisting non-AP STA and may set the DPS Assisting Support field to 1 in the UHR Capabilities element in Management frames that it transmits. A UHR AP that has dotH UHRDPSAssistinglmplemented equal to 1 is called a DPS Assisting AP and may set the DPS Assisting Support field to 1 in the UHR Capabilities element in Management frames that it transmits. Otherwise, the UHR AP or non-AP STA may set the DPS Assisting Support field to 0.Docket No.: 24-3051 PCT

[0376] A DPS STA may be either a DPS non-AP STA or a DPS mobile AP. An AP that is not a UHR mobile AP may have dot1 1 UHRDPSImplemented equal to 0.

[0377] A UHR non-AP STA that has dot11 UHRDPSImplemented equal to 1 may set the DPS Support field to 1 in the UHR Capabilities element in Management frames that it transmits, and otherwise may set the DPS Support field to 0. A non-AP UHR STA that has dot1 1 UHRDPSImplemented equal to 1 and that enables its DPS mode may be referred to as a DPS non-AP STA.

[0378] When a non-AP STA that supports DPS mode (re)associates with an AP, DPS mode may be disabled by default for the non-AP STA. A UHR non-AP STA that supports DPS mode and that intends to enable, disable, or update the parameters of DPS mode may follow a procedure defined in an IEEE 802.11 standard amendment. In the UHR OMP request sent to enable or update the DPS mode parameters, the non-AP STA may include the DPS Operation Parameter field. The associated AP may accept the request and follow a procedure defined in an IEEE 802 1 1 standard amendment.

[0379] The ICF frame addressed to one or more DPS STAs may include an l-FCS if at least one of the recipient DPS STAs has indicated a nonzero DPS padding delay, and may include sufficient padding to satisfy the padding requirements of the DPS STAs addressed by that ICF as defined in an IEEE 802.1 1 standard amendment.

[0380] When a DPS assisting AP sends an ICF that is an MU-RTS Trigger frame to a DPS non-AP STA that can receive frames other than ICF in LC mode, the DPS assisting AP may set the Remain In LC Mode field to 1 in the User Info field of the MU-RTS Trigger frame addressed to the DPS non-AP STA. Otherwise, the DPS assisting AP may set the Remain In LC Mode field in the MU-RTS Trigger frame to 0.

[0381] If the Remain In LC Mode field is equal to 1 , the DPS assisting AP may ensure that all SU PPDUs transmitted to the DPS non-AP STA, and all RUs allocated to the DPS non-AP STA within MU PPDUs and TB PPDUs that are initiated by the transmission of this frame, do not exceed the LC-mode parameters in the DPS Operation Parameters of the STA in parameterized mode, or the default mode parameters in default mode. The DPS assisting AP may also follow the procedure in this subclause and may include the l-FCS and padding in the MU-RTS Trigger frame if the DPS non-AP STA has enabled DPS with a nonzero DPS padding delay.

[0382] A DPS non-AP STA that receives an MU-RTS Trigger frame with the Remain In LC Mode field equal to 1 may remain in LC mode after receiving the ICF. A DPS non-AP STA that receives an MU-RTS Trigger frame with the Remain In LC Mode field equal to 0 may transition to HC mode after receiving the ICF.

[0383] DPS operation may allow a DPS STA to operate in LC mode and to transition to HC mode upon reception of an ICF transmitted by its associated AP.

[0384] If at least one non-AP STA addressed by a DPS assisting AP’s ICF has indicated a nonzero padding delay to transition from LC mode to HC mode, and none of the addressed non-AP STAs are operating with DUO mode enabled, then the DPS assisting AP may use an MU-RTS Trigger frame or a BSRP Trigger frameDocket No.: 24-3051 PCT as the ICF to solicit the transition from LC mode to HC mode. If one addressed STA is operating with DUO mode enabled, then the DPS assisting AP may use a BSRP T rigger frame or an individually addressed BSRP NTB Trigger frame as the ICF.

[0385] If none of the addressed non-AP STAs have indicated a nonzero padding delay, and none are operating with DUO mode enabled, the DPS assisting AP may use one of RTS (when a single TXOP responder condition is met), the MU-RTS Trigger frame, or the BSRP Trigger frame as the ICF. If one addressed STA is operating with DUO mode enabled, the DPS assisting AP may use a BSRP T rigger frame or an individually addressed BSRP NTB Trigger frame as the ICF.

[0386] A DPS non-AP STA in HC mode may follow the enhanced multi-link single-radio (EMLSR) rules for switching back to listening mode to transition to LC mode.

[0387] A DPS STA in LC mode may be capable of exchanging frames under one of two modes indicated by the Parameterized Mode field in the DPS Operation Parameters of the UHR Mode Change element. If the Parameterized Mode field is equal to 0, the STA may operate in default mode using 20 MHz bandwidth, 1 SS, and a non-HT PPDU format with data rates of 6, 12, and 24 Mb / s. If the Parameterized Mode field is equal to 1 , the STA may operate in parameterized mode using PPDU formats up to UHR PPDU with the bandwidth, NSS, and MCS announced in its DPS Operation Parameters when enabling DPS mode.

[0388] A DPS non-AP STA in HC mode may transmit and receive the same PPDUs as if DPS mode were not enabled.

[0389] If a DPS non-AP STA enables DPS with the ICF Required field set to 0, a DPS Assisting AP may initiate frame exchanges without sending an ICF so long as the frames use parameters compatible with the LC-mode parameters of the DPS STA. However, a DPS non-AP STA may not enable DPS with the ICF Required field set to 0 when operating on an eMLSR link.

[0390] If a DPS non-AP STA enables DPS with the ICF Required field set to 1 , the DPS Assisting AP may initiate any frame exchange with that STA only by first transmitting an ICF.

Claims

Docket No.: 24-3051 PCTCLAIMSWhat is claimed is:1 . A method comprising: transitioning, by a first station (STA), to a low capability mode of a power save mode; receiving, by the first STA from an access point (AP), a trigger frame indicating( / allocating) the first STA and a second STA; transitioning, by the first STA, from the low capability mode to a high capability mode of the power save mode; transmitting, by the first STA to the AP, an uplink (UL) frame soliciting an acknowledgment frame; in response to the UL frame, receiving, by the STA from the AP, the acknowledgment frame, wherein the acknowledgment frame indicates absence at the AP of a downlink buffered bufferable unit (BU) for the first STA and is addressed to the first STA and the second STA; and based on receiving the acknowledgment frame, transitioning, by the STA, from the high capability mode to the low capability mode.

2. A method comprising: transmitting, by a first station (STA) to an access point (AP) and while in a first power state of a power save mode, a first frame soliciting a second frame; in response to the first frame, receiving, by the first STA from the AP, the second frame, wherein the second frame indicates absence at the AP of a downlink (DL) buffered bufferable unit (BU) for the first STA; and based on receiving the second frame, transitioning, by the first STA, from the first power state to a second power state of the power save mode.

3. The method of claim 2, wherein the power save mode comprises a dynamic power save mode.

4. The method of any of claims 2-3, wherein the first power state comprises a high power state, a high capability mode, a high power capability mode, or a high power capability state.

5. The method of any of claims 2-4, wherein while in the first power state the first STA transmits a frame using at least one of an operating bandwidth (BW), a number of spatial stream (NSS), and a modulation coding scheme (MCS) that is higher than in the second power state.

6. The method of any of claims 2-5, wherein the second power state comprises a low power state, a low capability mode, a low power capability mode, or a low power capability state.

7. The method of any of claims 2-6, wherein while in the second power state the first STA transmits a frame using one or more of: a 20MHz bandwidth (BW), one spatial stream (SS), a limited data rate compared with the first power state, a limited PPDU format set compared with the first power state, and a limited control frame set compared with the first power state.Docket No.: 24-3051 PCT8. The method of any of claims 2-7, wherein the first frame comprises a data frame, a quality of service (QoS) data frame, a management frame, a control frame, a QoS null frame, or an action frame.

9. The method of any of claims 2-8, wherein the second frame comprises at least one of an acknowledgement (Ack) frame, a blockack (BA) frame, a compressed BA frame, a multi-STA BA frame, or a control frame.

10. The method of any of claims 2-9, wherein an address subfield of the second frame comprises an individual address ( / a unicast address) or a broadcast address.11 . The method of claim 10, wherein the address subfield of the second frame comprises a receiver address ( / Address 1).

12. The method of any of claims 10-11 , wherein based on the address subfield comprising the broadcast address, the second frame indicates ( / allocates) one or more STAs.

13. The method of claim 12, wherein the second frame indicating the one or more STAs comprises the second frame comprising one or more per association identifier (AID) traffic identifier (TID) info (Per AID TID Info) subfields corresponding to each of the one or more STAs.

14. The method of any of claims 2-13, wherein the first frame comprises an ack policy subfield indicating implicit BAR (00).

15. The method of any of claims 2-14, further comprising: receiving, by the first STA from the AP, a third frame indicating ( / allocating) the first STA, wherein the first STA is in the second power state; and transitioning, by the first STA, from the second power state to the first power state.

16. The method of claim 15, wherein the third frame comprises at least one of:(I) a trigger frame, a basic Trigger frame, or an initial control frame; or(II) a receiver address set to a media access control (MAC) address of the first STA.

17. The method of any of claims 15-16, wherein: the third frame indicates a second STA; and the second frame indicates the second STA.

18. The method of claim 17, wherein the third frame comprises a broadcast receiver address.

19. The method of any of claims 2-18, wherein the second frame indicating the absence of the DL buffered BU at AP for the first STA comprises the second frame comprising a more data (MD) subfield, of a medium access control (MAC) header of the second frame, equal(Zset) to 0.

20. The method of any of claims 2-19, wherein the second frame indicates an allowance of transitioning, by the first STA, from the first power state to the second power state.21 . The method of claim 20, wherein the indication of allowance comprises: (i) at least one of a STA- identifier (ID) list, a STA indication bitmap, or a group ID, or (ii) the AP not having a buffered BU for the first STA.Docket No.: 24-3051 PCT22. The method of claim 21 , wherein the STA-ID list comprises one or more STA IDs identifying: (i) one or more STAs for which the AP has buffered traffic, or (ii) one or more STAs that are allowed to transition to the second power state after the second frame.

23. The method of claim 21 , wherein the STA indication bitmap comprises a bitmap identifying: (i) one or more STA for which the AP has buffered traffic, or (ii) one or more STAs that are allowed to transition to the second power state after the second frame.

24. The method of claim 23, wherein each bit of the STA indication bitmap corresponds to a respective STA indicated in a per AID TID info subfield of the second frame.

25. The method of any of claims 21-24, wherein the group ID comprises an identifier of a group corresponding to: (i) one or more STAs for which the AP has buffered traffic, or (ii) one or more STAs that are allowed to transition to second power state after the second frame.

26. The method of any of claims 2-25, wherein the second frame further comprises a subfield indicating whether a more data subfield of a medium access control (MAC) header of the second frame is valid.

27. The method of any of claims 2-26, further comprising: in response to a fourth frame, receiving, by the first STA from the AP, a fifth frame indicating presence at the AP of at least one DL buffered BU for the first STA; and based on receiving the fifth frame, maintaining( / retaining / keeping), by the first STA, the first power state.

28. The method of claim 27, wherein the fifth frame indicating the presence of the at least one DL buffered BU at AP for the first STA comprises the fifth frame comprising a MD subfield, of a MAC header of the fifth frame, equal(Zset) to 1 .

29. The method of any of claims 27-28, wherein the fifth frame indicates disallowance of transitioning, the first STA, from the first power state to the second power state.

30. The method of claim 29, wherein the fifth frame indicating the disallowance comprises the AP having buffered traffic for the first STA.31 . The method of claim 30, wherein the fifth frame indicating the disallowance comprises the fifth frame comprising at least one of a STA-ID list, a STA indication bitmap, or a group ID.

32. The method of any of claims 27-31 , further comprising transitioning, by the first STA, to the second power state based on a first condition.

33. The method of claim 32, wherein the first condition comprises at least one of: not receiving, by the first STA from the AP and during a first time period, any frame after receiving the fifth frame indicating the presence at the AP of the at least one DL buffered BU; receiving, by the first STA from the AP and during the first time period, a frame that is addressed to another STA; orDocket No.: 24-3051 PCT receiving, by the first STA from the AP and during the first time period, a frame that is not addressed to the first STA.

34. The method of claim 33, further comprising transmitting, by the first STA to the AP, a sixth frame indicating the first time period.

35. The method of claim 34, wherein the sixth frame comprises a probe request frame, an association request frame, an individually addressed management frame, a control frame, a QoS data / null frame, or an action frame.

36. The method of claim 33, further comprising receiving, by the first STA from the AP, a seventh frame indicating the first time period.

37. The method of claim 36, wherein the seventh frame comprises a probe response frame, an association response frame, an individually addressed( / group addressed) management frame, a control frame, a QoS data / null frame, or an individually addressed( / group addressed) action frame.

38. The method of claim 33, wherein the first time period has a fixed value.

39. The method of claim 38, wherein the first time period is pre-configured.

40. The method of any of claims 33-39, wherein the AP does not transmit an initial control frame to the first STA during the first time period.41 . The method of any of claims 33-40, further comprising: receiving, by the first STA from the AP, a buffer status report poll (BSRP) trigger frame indicating / allocating the first STA; transmitting, by the first STA to the AP, a BSR frame; and after transmitting the BSR frame, transitioning, by the first STA, to the second power state based on the first condition.

42. The method of claim 41 , further comprising maintaining, by the first STA, the first power state based on receiving an eighth frame within the first time period.

43. The method of claim 42, wherein the eighth frame comprises a frame that is addressed to the first STA.

44. A method comprising: transmitting, by a station (STA) to an access point (AP) and while in a high capability mode of a power save mode, a first frame not soliciting a second frame; and based on a first condition, transitioning, by the STA, from the high capability mode to a low capability mode of the power save mode.

45. The method of claim 44, wherein the first frame comprises a buffer status report (BSR) frame, an Ack frame, a blockack (BA) frame, a control frame, a management frame, a quality of service (QoS) data frame, a QoS null frame, or an action frame.

46. The method of any of claims 44-45, wherein the first condition comprises one of:Docket No.: 24-3051 PCT receiving, by the STA from the AP and during a first time period, a third frame that is not addressed to the STA; or not receiving, by the STA from the AP and during the first time period, any frame.

47. The method of claim 46, further comprising transmitting, by the STA to the AP, a fourth frame indicating the first time period.

48. The method of claim 47, wherein the fourth frame comprises a probe request frame, an association request frame, an individually addressed management frame, a control frame, a QoS data / null frame, or an action frame.

49. The method of claim 46, further comprising receiving, by the STA from the AP, a fifth frame indicating the first time period.

50. The method of claim 49, wherein the fifth frame comprises a probe response frame, an association response frame, an individually addressed( / group addressed) management frame, a control frame, a QoS data / null frame, or an individually addressed( / group addressed) action frame.51 . The method of claim 46, wherein the first time period has a fixed value.

52. The method of claim 51 , wherein the first time period is pre-configured.

53. The method of any of claims 46-52, wherein the AP does not transmit an initial control frame to the STA during the first time period.

54. The method of any of claims 46-53, wherein the third frame is addressed to another STA.

55. The method of any of claims 46-54, wherein the first time period starts after transmitting the first frame.

56. The method of any of claims 44-55, wherein the second frame comprises an immediate response frame.

57. A method comprising: receiving, by a station (STA) from an access point (AP) and while in a high capability mode of a power save mode, a first frame not soliciting a second frame; and based on a first condition, transitioning, by the STA, from the high capability mode to a low capability mode of the power save mode.

58. The method of claim 57, wherein the first frame comprises an Ack frame, a blockack (BA) frame, a multi-STA BA frame, a control frame, a management frame, a QoS data frame, a QoS null frame, or an action frame.

59. The method of any of claims 57-58, wherein the first condition comprises one of: receiving, by the STA from the AP and during a first time period, a third frame that is not addressed to (is not indicating) the STA (is addressed to or other STA); or not receiving, by the STA from the AP and during the first time period, any frame.Docket No.: 24-3051 PCT60. The method of claim 59, wherein the third frame is a frame not addressed to (not indicating) the STA or a frame addressed to another STA.61 . The method of any of claims 59-60, wherein the first time period starts after receiving the first frame.

62. The method of any of claims 57-61 , wherein the second frame comprises an immediate response frame.

63. A method comprising: receiving, by a station (STA) from an access point (AP) and while in a high capability mode of a power save mode, a first frame: soliciting a second frame; and indicating absence at the AP of a buffered bufferable unit (BU) for the STA; transmitting, by the STA to the AP, the second frame; and based on the first frame indicating the absence at the AP of the buffered BU for the STA and after transmitting the second frame, transitioning, by the STA, from the high capability mode to a low capability mode of the power save mode.

64. The method of claim 63, wherein the first frame comprises a downlink (DL) frame, a control frame, a management frame, a quality of service (QoS) data frame, a QoS null frame, an acknowledgment (Ack) frame, a blockack (BA) frame, a multi-STA BA frame, or an action frame.

65. The method of any of claims 63-64, wherein the second frame comprises an immediate response frame (Ack or BA).

66. The method of any of claims 63-65, wherein the first frame soliciting the second frame comprises the first frame having an Ack policy subfield equal to implicit BAR (00) or HETP Ack (01)67. The method of any of claims 63-66, further comprising: receiving, by the STA from the AP, a third frame: soliciting a fourth frame; and indicating a presence at the AP of at least one buffered BU for the STA; transmitting, by the STA to the AP, the fourth frame; and based on the third frame indicating the presence at the AP of at least one buffered BU for the STA and after transmitting the fourth frame, maintaining, by the STA, ( / retaining / keeping) the high capability mode.

68. The method of any of claims 63-67, further comprising: receiving, by the STA from the AP, a fifth frame: not soliciting a sixth frame; and indicating an absence at the AP of buffered BUs for the STA; andDocket No.: 24-3051 PCT based on the fifth frame indicating the absence at the AP of buffered BUs for the STA and after receiving the fifth frame, transitioning, by the STA, from the high capability mode to the low capability mode.

69. The method of any of claims 63-68, further comprising: receiving, by the STA from the AP, a seventh frame: not soliciting an eighth frame; and indicating a presence at the AP of buffered BUs for the STA; and based on the seventh frame indicating the presence at the AP of buffered BUs for the STA and after receiving the seventh frame, maintaining, by the STA, ( / retaining / keeping) the high capability mode.

70. The method of claim 69, wherein the seventh frame not soliciting the eighth frame comprises the seventh frame having an Ack policy subfield equal to no Ack (10) or BA (11 ).71 . A method comprising: receiving, by a first station (STA) from an access point (AP) and while in a first power state of a power save mode, a first frame indicating absence at the AP of a downlink (DL) buffered bufferable unit (BU) for the first STA; and based on receiving the first frame, transitioning, by the STA, from the first power state to a second power state (low capability mode) of the power save mode.

72. A device comprising: one or more processors; and memory storing instructions that, when executed by the one or more processors, cause the device to perform a method according to any of claims 1-71 .

73. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors, cause the one or more processors to perform a method according to any of claims 1-

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