Coordinated channel access in wireless communication system

Abstract

The invention relates to coordinated channel access in a wireless communication system. The present disclosure relates to methods, systems, and apparatus for enhanced coordinated channel access including an access point (AP) and a non-access point (non-AP). A first non-AP of a set of at least two non-access points (non-APs) may receive signaling including information corresponding to a transmit opportunity (TXOP) from a second non-AP of the set of at least two non-APs. Additionally, the first non-AP may transmit first data to one or more devices according to the information corresponding to the TXOP and scheduling information for the set of at least two non-APs, where the first data is transmitted to the one or more devices in at least a portion of the TXOP.

Description

Technical Field

[0001] The present application relates to wireless communications, including techniques for wireless communications between wireless stations and / or access points in a wireless networking system.

[0002] Related technical description

[0003] The use of wireless communication systems is growing rapidly. In addition, wireless communication technology has evolved from voice communications only to also include the transmission of data such as the Internet and multimedia content. A common short-range / medium-range wireless communication standard is the Wireless Local Area Network (WLAN). Most modern WLANs are based on the IEEE 802.11 standard (and / or 802.11 for short) and are sold under the Wi-Fi brand name. A WLAN network links one or more devices to a wireless access point, which in turn provides a connection to the wider area Internet.

[0004] In an 802.11 system, devices that are wirelessly connected to each other are referred to as "stations," "mobile stations," "user devices," "user equipment," or STAs or UEs for short. A wireless station may be a wireless access point or a wireless client (and / or a mobile station). An access point (AP), also known as a wireless router, acts as a base station for a wireless network. The AP sends and receives radio frequency signals for communicating with wireless client devices. The AP may also be coupled to the Internet by wire and / or wireless means. A wireless client operating on an 802.11 network may be any of a variety of devices, such as a laptop, tablet device, smart phone, smart watch, or fixed device such as a desktop computer. Wireless client devices are referred to herein as user equipment (and / or UE for short). Some wireless client devices are also collectively referred to herein as mobile devices or mobile stations (but as mentioned above, wireless client devices may also be stationary devices as a whole).

[0005] Mobile electronic devices may take the form of smartphones or tablets that are commonly carried by users. Wearable devices (also known as accessory devices) are a newer form of mobile electronic devices, an example being smart watches. Additionally, low-cost, low-complexity wireless devices intended for static or dynamic deployment are also increasing rapidly as part of the development of the "Internet of Things". In other words, the complexity, capabilities, business models and other features of the devices required are becoming increasingly broad.

[0006] Some WLANs may utilize multi-link operation (MLO), for example, to use multiple channels (e.g., links) concurrently. APs and / or STAs with MLO capabilities may be referred to as multi-link devices (MLDs). For example, an AP with MLO capabilities may be referred to as an AP-MLD, and an MLO-capable STA that does not act as an AP may be referred to as a non-AP MLD. Improvements in the art are desired. Summary of the invention

[0007] Embodiments described herein relate to methods, systems, and apparatus for enhanced coordinated channel access in a wireless networking system including access points (APs) and non-access points (non-APs).

[0008] In some embodiments, a first non-access point (non-AP) station in a group of at least two non-AP stations may receive signaling including information corresponding to a transmit opportunity (TXOP) from a second non-AP station in the group of at least two non-AP stations. Additionally, the first non-AP station may send first data to one or more devices based on the information corresponding to the TXOP and scheduling information associated with the group of at least two non-AP stations, wherein the first data is sent to the one or more devices in at least a portion of the TXOP.

[0009] According to some embodiments, the signaling including information corresponding to the TXOP may indicate that only the first non-AP station is to use at least a portion of the TXOP to send the first data. In addition, according to some embodiments, when the first non-AP station completes sending the first data before the end of the TXOP, the method may further include: sending a control frame to a group address associated with the group of at least two non-AP stations to terminate the TXOP, the control frame message including one or more parameters.

[0010] According to further embodiments, the method may further include: sending one or more multi-user block acknowledgement requests (MU-BARs) to the at least two non-AP sites, and receiving one or more block acknowledgements (BAs) from the at least two non-AP sites. Additionally or alternatively, the signaling including information corresponding to the TXOP may instruct the first non-AP site and one or more other non-AP sites in the group of at least two non-AP sites to use at least a portion of the TXOP to send data to the one or more devices, respectively. In addition, according to some embodiments, when one of the at least two non-AP sites completes corresponding data transmission before the end of the TXOP, the method may further include: receiving a control frame to terminate the TXOP based on a group address associated with the group of at least two non-AP sites, the control frame including one or more parameters.

[0011] In some embodiments, the group of at least two non-AP sites may be associated with a group address or a group identifier (ID). Additionally or alternatively, the first data may be sent to one or more devices, the one or more devices including at least one of the following: one or more APs, one or more mobile APs, one or more non-APs, or one or more non-AP sites (STAs). According to some embodiments, the signaling including information corresponding to a transmit opportunity (TXOP) may further include a control frame including addresses of the group of at least two non-AP sites. In some embodiments, the method may be performed after one or more contention periods have passed.

[0012] According to some embodiments, a processor may include a memory storing instructions that, when executed, cause a first non-access point (non-AP) station to: establish a wireless link with an access point (AP) via an access channel. Additionally, the instructions are further executable to cause the first non-AP station to: send a request corresponding to a transmit opportunity (TXOP) and including an address of the first non-AP station to the AP. Furthermore, the instructions are further executable to cause the first non-AP station to: receive a response from the AP, and send first data in at least a portion of the TXOP according to scheduling information associated with the first non-AP station.

[0013] In some embodiments, when the first non-AP station completes sending the first data before the end of the TXOP, the instructions are further executable to cause the first non-AP station to: broadcast one or more control frames to a group address of at least two non-AP stations to invite the at least two non-AP stations to send. In addition, the request may include an instruction to cause only one of the at least two non-AP stations to send data using at least a portion of the TXOP. Additionally or alternatively, the instructions are further executable to cause the first non-AP station to: receive one or more invitation to send (ITS) messages from one or more non-AP stations of the at least two non-AP stations. In some embodiments, the one or more ITS messages may indicate to the first non-AP station that the non-AP station has no data to send or that the non-AP station has completed data transmission before a portion of the TXOP ends.

[0014] According to a further embodiment, an access point (AP) may include a radio component and a processor that is operably coupled to the radio component. In addition, the processor may be configured to cause the AP to: establish a wireless link with a first non-AP site in a group of at least two non-access points (non-APs) via an access channel. Additionally, the processor may be configured to cause the AP to: receive signaling from the first non-AP site, the signaling including at least one of an address of the group of at least two non-APs or a single non-AP site and a transmit opportunity (TXOP) sharing request indication. In addition, the processor may be configured to cause the AP to: send a response including a TXOP sharing indication to the first non-AP site, and send additional responses including TXOP sharing indications to additional non-AP sites in the group of at least two non-AP sites.

[0015] In some embodiments, the processor may be further configured to cause the AP to: send one or more null data packet feedback report polls (NFRPs) to one or more non-AP stations in the group of at least two non-AP stations. Additionally, the processor may be further configured to cause the AP to: send one or more request to transmit (RTS) messages to one or more non-AP stations in the group of at least two non-AP stations. Additionally or alternatively, according to some embodiments, the duration of the RTS message may be the maximum allowed shared duration. In some embodiments, the processor may be further configured to cause the AP to: receive one or more control frames from one or more non-AP stations in the group of at least two non-AP stations. Additionally, according to some embodiments, the duration of the control frame may indicate that the requested duration is less than or equal to the maximum allowed shared duration. In addition, the processor may be further configured to cause the AP to: perform point coordination function inter-frame space (PIFS) recovery of the access channel in response to one or more non-AP stations in the group of at least two non-AP stations completing transmission before the assigned time.

[0016] This disclosure is intended to provide a brief overview of some of the topics described in this document. Therefore, it should be understood that the above features are only examples and should not be construed as narrowing the scope or essence of the topics described herein in any way. Other features, aspects, and advantages of the topics described herein will become apparent through the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] A better understanding of the present subject matter may be obtained when the following detailed description of the embodiments is considered in conjunction with the accompanying drawings.

[0018] Figure 1 An example wireless communication system is illustrated in accordance with some embodiments.

[0019] Figure 2 An example simplified block diagram of a wireless device according to some embodiments is illustrated.

[0020] Figure 3 An example WLAN communication system is illustrated in accordance with some embodiments.

[0021] Figure 4 An example simplified block diagram of a WLAN access point (AP) is illustrated in accordance with some embodiments.

[0022] Figure 5 An example simplified block diagram of a wireless station (STA) according to some embodiments is illustrated.

[0023] Figure 6 An example simplified block diagram of a wireless node according to some embodiments is illustrated.

[0024] Figures 7 and 8 Various examples of MLDs according to some embodiments are illustrated.

[0025] FIG. 9A to FIG. 9B Example aspects of channel access contention between devices according to some embodiments are illustrated.

[0026] FIG. 10A to FIG. 10C Example aspects of transmit opportunity (TXOP) sharing according to some embodiments are illustrated.

[0027] Fig.11 Various example aspects of TXOP sharing groups according to some embodiments are illustrated.

[0028] Fig.12 is a communication flow diagram illustrating an example method of enhanced STA coordinated channel access according to some embodiments.

[0029] Fig.13 is a communication flow diagram illustrating additional example methods for enhanced STA coordinated channel access according to some embodiments.

[0030] Fig.14 is a communication flow diagram illustrating an example method of enhanced AP coordinated channel access according to some embodiments.

[0031] FIG. 15A to FIG. 27 Various example aspects of enhanced coordinated channel access according to some embodiments are illustrated.

[0032] Although the features described herein are susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and described in detail herein. However, it should be understood that the drawings and detailed description thereof are not intended to be limited to the specific forms disclosed, but on the contrary, are intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the appended claims. DETAILED DESCRIPTION

[0033] Acronyms

[0034] Various acronyms are used throughout this patent application. The definitions of the most prominent acronyms used that may appear throughout this patent application are as follows:

[0035] UE: User Equipment

[0036] AP: Access Point

[0037] STA: Wireless Station

[0038] TX: Send / Transmit

[0039] RX: Receive / Receive

[0040] DL: Downlink

[0041] UL: Uplink

[0042] MLD: Multi-Link Device

[0043] LAN: Local Area Network

[0044] WLAN: Wireless Local Area Network

[0045] RAT: Radio Access Technology

[0046] ACK: Acknowledgement

[0047] BA: Block Acknowledgement

[0048] NACK: Negative Acknowledgement

[0049] N-BA: Negative Block Acknowledgement

[0050] OTA: Over the air

[0051] SU: Single User

[0052] MU: Multi-User

[0053] MAC: Media Access Control

[0054] CPE: Enhanced client privacy

[0055] BSS: Basic Service Set

[0056] OBSS: Overlapping Basic Service Set

[0057] SN: Serial number

[0058] PN: Group Number

[0059] TID: Transaction Identifier

[0060] AID: Association Identifier

[0061] SSID: Service Set Identifier

[0062] SAP: Service Access Point

[0063] EDCA: Enhanced Distributed Channel Access

[0064] PPDU: Physical Protocol Data Unit

[0065] TXOP: Transmit Opportunity

[0066] TWT SP: Target wake-up time service period

[0067] P2P: Peer to Peer

[0068] RDG: Reverse Direction Grant

[0069] NAN: Neighborhood Area Network

[0070] RTS: Request to Send

[0071] CTS: Clear to send

[0072] MU-BAR: Multi-User Block Acknowledgement Request

[0073] ITS: Invitation to Send

[0074] PCF: Point Coordination Function

[0075] PIFS: PCF interframe space

[0076] TXS: Triggered Transmit Opportunity Sharing

[0077] TA: sender address

[0078] RA: Receiver Address

[0079] ICF: Initial Control Frame

[0080] NAV: Network Allocation Vector

[0081] CF: No competition

[0082] NDP: Null Data Packet

[0083] NFRP: NDP Feedback Report Poll

[0084] RD UL MU-MIMO: Reverse Direction Multi-User - Multiple Input Multiple Output

[0085] the term

[0086] The following is a glossary of terms used in this disclosure:

[0087] Memory medium—any of various types of non-transitory memory devices or storage devices. The term "memory medium" is intended to include installation media, such as CD-ROM, floppy disk, or tape devices; computer system memory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory, such as flash memory, magnetic media, for example, hard disk drives or optical storage devices; registers or other similar types of memory elements, etc. The memory medium may also include other types of non-transitory memory or combinations thereof. In addition, the memory medium may be located in a first computer system executing a program, or may be located in a different second computer system connected to the first computer system via a network such as the Internet. In the latter case, the second computer system may provide program instructions to the first computer for execution. The term "memory medium" may include two or more memory media that may reside in different locations in different computer systems connected, for example, via a network. The memory medium may store program instructions (e.g., embodied as a computer program) that may be executed by one or more processors.

[0088] Carrier Media—Memory media as described above, as well as physical transmission media such as a bus, network, and / or other physical transmission media that convey signals such as electrical, electromagnetic, or digital signals.

[0089] Computer System—Any of various types of computing or processing systems, including a personal computer system (PC), a mainframe computer system, a workstation, a network appliance, an Internet appliance, a personal digital assistant (PDA), a television system, a grid computing system, or other devices or combinations of devices. In general, the term "computer system" may be broadly defined to encompass any device (and / or combination of devices) having at least one processor that executes instructions from a memory medium.

[0090] Mobile Device (and / or Mobile Station)—Any of various types of computer system devices that are mobile or portable and that perform wireless communications using WLAN communications. Examples of mobile devices include mobile phones or smart phones (e.g., iPhone TM , based on Android TM phones), and tablets such as iPads TM、Samsung Galaxy TM etc. Various other types of devices would fall into this category if they include Wi-Fi or both cellular and Wi-Fi communication capabilities, such as laptop computers (e.g., MacBooks TM ), portable gaming devices (e.g., Nintendo DS TM , PlayStation Portable TM 、Gameboy Advance TM , iPhone TM ), portable Internet devices and other handheld devices, and wearable devices such as smart watches, smart glasses, headphones, pendants, earbuds, etc. In general, the term "mobile device" can be broadly defined to include any electronic, computing and / or communication device (and / or combination of devices) that a user can easily transport and that is capable of wireless communication using WLAN or Wi-Fi.

[0091] Wireless device (and / or wireless station) - any of various types of computer system devices that perform wireless communications using WLAN communications. As used herein, the term "wireless device" may refer to a mobile device as defined above or a fixed device such as a fixed wireless client or wireless base station. For example, a wireless device may be any type of wireless station for an 802.11 system, such as an access point (AP) or a client station (STA or UE). Other examples include televisions, media players (e.g., AppleTV TM ,Roku TM , Amazon FireTV TM , Google Chromecast TM etc.), refrigerators, washing machines, thermostats, etc.

[0092] WLAN—The term "WLAN" has the full scope of its ordinary meaning and includes at least a wireless communication network or RAT that is served by WLAN access points and provides connectivity to the Internet through these access points. Most modern WLANs are based on the IEEE 802.11 standard and are marketed under the name "Wi-Fi". WLAN networks are distinct from cellular networks.

[0093] Processing Element - refers to various specific implementations of digital circuits that perform functions in a computer system. Additionally, a processing element may refer to various specific implementations of analog or mixed-signal (a combination of analog and digital) circuits that perform functions (and / or multiple functions) in a computer or computer system. Processing elements include, for example, circuits such as integrated circuits (ICs), ASICs (application specific integrated circuits), portions or circuits of individual processor cores, entire processor cores, individual processors, programmable hardware devices such as field programmable gate arrays (FPGAs), and / or larger portions of systems including multiple processors.

[0094] Automatically—refers to an action or operation being performed by a computer system (e.g., software executed by a computer system) or a device (e.g., a circuit, a programmable hardware element, an ASIC, etc.) without the action or operation being directly specified or performed by a user input. Thus, the term "automatically" is in contrast to an operation being manually performed or specified by a user, where the user provides input to directly perform the operation. An automatic procedure may be initiated by input provided by a user, but the subsequent "automatically" performed actions are not specified by the user, such as not being performed "manually," where the user specifies each action to be performed. For example, a user filling out an electronic form by selecting each field and providing input specifying information (e.g., by typing in information, selecting checkboxes, radio selections, etc.) is not manually filling out the form, even though the computer system must update the form in response to the user action. The form may be automatically filled out by a computer system, where the computer system (e.g., software executed on the computer system) analyzes the fields of the form and fills out the form without any user input specifying the answers to the fields. As indicated above, a user may invoke automatic filling out of a form, but not participate in the actual filling out of the form (e.g., the user does not manually specify the answers to the fields but rather they are automatically completed). This specification provides various examples of operations that are automatically performed in response to actions that a user has taken.

[0095] Concurrency - refers to parallel execution or implementation, where tasks, processes, signaling, messages, or programs are executed in a manner that at least partially overlaps. For example, concurrency can be achieved using "strong" or strict parallelism, where tasks are executed (at least partially) in parallel on corresponding computing elements, or using "weak parallelism", where tasks are executed in an interleaved manner (e.g., by time multiplexing of execution threads).

[0096] Configured to - Various components may be described as being "configured to" perform one or more tasks. In such contexts, "configured to" is a broad statement that generally means "having a structure" that performs one or more tasks during operation. Thus, a component can be configured to perform a task even when the component is not currently performing the task (e.g., a set of electrical conductors can be configured to electrically connect a module to another module even when the two modules are not connected). In some contexts, "configured to" can be a broad statement that generally means "having a structure" that performs one or more tasks during operation. Thus, the component can be configured to perform a task even when the component is not currently turned on. Typically, the circuitry that forms the structure corresponding to "configured to" may include hardware circuitry.

[0097] For ease of description, various components may be described as performing one or more tasks. Such descriptions should be interpreted as including the phrase "configured to". The statement that a component is configured to perform one or more tasks is expressly intended not to invoke the interpretation of 35 U.S.C. §112(f) for that component.

[0098] Figure 1 to Figure 2 —Wireless communication system

[0099] Figure 1 An exemplary (and simplified) wireless communication system is illustrated in which various aspects of the present disclosure may be implemented. Figure 1 The system is only one example of possible systems, and embodiments of the present disclosure may be implemented in any of a variety of systems as desired.

[0100] As shown, the exemplary wireless communication system includes a ("first") wireless device 102 communicating with another ("second") wireless device. The first wireless device 102 and the second wireless device 104 may communicate wirelessly using any of a variety of wireless communication techniques, including possibly ranging wireless communication techniques.

[0101] As one possibility, the first wireless device 102 and the second wireless device 104 may perform ranging using a wireless local area network (WLAN) communication technology (e.g., IEEE 802.11 / Wi-Fi based communication) and / or a technology based on WLAN wireless communication. One or both of the wireless device 102 and the wireless device 104 may also be able to communicate via one or more additional wireless communication protocols, such as any of Bluetooth (BT), Bluetooth Low Energy (BLE), Near Field Communication (NFC), LTE, Advanced LTE (LTE-A), NR, Ultra Wideband (UWB), etc.

[0102] Wireless device 102 and wireless device 104 may be any of various types of wireless devices. As one possibility, one or more of wireless devices 102 and / or 104 may be substantially portable wireless user equipment (UE) devices, such as a smartphone, a handheld device, a wearable device (such as a smart watch), a tablet, a motor vehicle, or virtually any type of wireless device. As another possibility, one or more of wireless device 102 and / or wireless device 104 may be substantially stationary devices, such as a set-top box, a media player (e.g., an audio or audio-visual device), a game console, a desktop computer, an appliance, a door, an access point, a base station, or any of various other types of devices.

[0103] Each of the wireless device 102 and the wireless device 104 may include wireless communication circuitry configured to facilitate the performance of wireless communications, which may include various digital and / or analog radio frequency (RF) components, a processor configured to execute program instructions stored in a memory, a programmable hardware element such as a field programmable gate array (FPGA), and / or any of various other components. The wireless device 102 and / or the wireless device 104 may use any or all of such components to perform any method implementation described herein, or any portion of any method implementation described herein.

[0104] Each of the wireless devices 102 and 104 may include one or more antennas for communicating using one or more wireless communication protocols. In some cases, one or more portions of the receive chain and / or transmit chain may be shared between multiple wireless communication standards; for example, the device may be configured to communicate using either Bluetooth or Wi-Fi using partially or fully shared wireless communication circuits (e.g., using shared radio components or at least shared radio components). The shared communication circuit may include a single antenna, or may include multiple antennas for performing wireless communication (e.g., for MIMO). Alternatively, the device may include an independent transmit chain and / or receive chain (e.g., including independent antennas and other radio components) for each wireless communication protocol configured to communicate with it. As another possibility, the device may include one or more radios or radio components shared between multiple wireless communication protocols, and one or more radios or radio components used exclusively by a single wireless communication protocol. For example, the device may include a shared radio component for communicating using one or more of LTE and / or 5G NR, and a separate radio component for communicating using each of Wi-Fi, UWB, and Bluetooth. Other configurations are also possible.

[0105] As mentioned above, it can be combined with Figure 1A wireless communication system of the present disclosure may be implemented to implement aspects of the present disclosure. For example, a wireless device (e.g., either of the wireless devices 102 or 104) may be configured to perform methods for robust discovery of new APs in an access point (AP) MLD, robust link addition to AP MLD association, AP beacon mode when adding an AP to or deleting an AP from an AP MLD, and robust BSS transition management (BTM) signaling for directing non-AP MLDs to the best AP MLD and the most suitable AP, and privacy improvement for associated non-AP MLDs.

[0106] Figure 6 An exemplary wireless device 100 (e.g., corresponding to wireless device 102 and / or wireless device 104) that may be configured for use in conjunction with various aspects of the present disclosure is illustrated. Device 100 may be any of a variety of types of devices and may be configured to perform any of a variety of types of functionality. Device 100 may be a substantially portable device, or may be a substantially fixed device, possibly including any of a variety of types of devices. Device 100 may be configured to perform one or more ranging wireless communication techniques or features, such as any of the techniques or features shown and / or described subsequently herein with respect to any or all of the figures.

[0107] As shown, device 100 may include processing element 101. Processing element may include or be coupled to one or more memory elements. For example, device 100 may include one or more storage media (e.g., memory 105), which may include any of various types of memory and may be used for any of various functions. For example, memory 105 may be RAM used as system memory for processing element 101. Other types and functions are also possible.

[0108] Additionally, device 100 may include wireless communication circuitry 130. The wireless communication circuitry may include any of a variety of communication elements (e.g., an antenna for wireless communication, analog and / or digital communication circuitry / controllers, etc.), and may enable the device to communicate wirelessly using one or more wireless communication protocols.

[0109] Note that in some cases, wireless communication circuitry 130 may include its own processing element (e.g., a baseband processor) in addition to processing element 101, for example. For example, processing element 101 may be an "application processor" whose primary function may be to support application layer operations in device 100, while wireless communication circuitry 130 may be a "baseband processor" whose primary function may be to support baseband layer operations in device 100 (e.g., to facilitate wireless communications between device 100 and other devices). In other words, in some cases, device 100 may include multiple processing elements (e.g., may be a multi-processor device). Other configurations utilizing a multi-processor architecture (e.g., instead of or in addition to an application processor / baseband processor configuration) are also possible.

[0110] Depending on the intended functionality of device 100, device 100 may additionally include any of a variety of other components (not shown) for implementing device functionality, which may also include processing elements and / or memory elements (e.g., audio processing circuitry), one or more power elements (which may rely on battery power and / or an external power source), user interface elements (e.g., a display, a speaker, a microphone, a camera, a keyboard, a mouse, a touch screen, etc.), and / or any of a variety of other components.

[0111] Components of device 100, such as processing element 101, memory 105 and wireless communication circuit 130, can be operably coupled via one or more interconnect interfaces, and the interconnect interface may include any of various types of interfaces, and may include a combination of multiple types of interfaces. As an example, a USB high-speed chip-to-chip (HSIC) interface can be provided for inter-chip communication between processing elements. Alternatively (and / or in addition), any of a universal asynchronous receiver-transmitter (UART) interface, a serial peripheral interface (SPI), an internal integrated circuit (I2C), a system management bus (SMBus) and / or various other communication interfaces can be used for communication between various device components. Other types of interfaces (e.g., an intra-chip interface for communication within processing element 101, a peripheral device interface for communicating with peripheral components inside or outside device 100, etc.) can also be provided as part of device 100.

[0112] Figure 3 —WLAN system

[0113] Figure 3An example WLAN system according to some embodiments is illustrated. As shown, the exemplary WLAN system includes a plurality of wireless client sites or devices (e.g., STA or user equipment (UE)) 106, which are configured to communicate with an access point (AP) 112 via a wireless communication channel 142. AP 112 may be a Wi-Fi access point. AP 112 may communicate with one or more other electronic devices (not shown) and / or another network 152 (such as the Internet) via a wired and / or wireless communication channel 150. Additional electronic devices (such as remote devices 154) may communicate with components of the WLAN system via network 152. For example, remote device 154 may be another wireless client site, a server associated with an application executed on one of STAs in STA 106, etc. The WLAN system may be configured to operate according to any of various communication standards such as various IEEE 802.11 standards. In some embodiments, at least one wireless device 106 is configured to communicate directly with one or more neighboring mobile devices without using access point 112.

[0114] Additionally, in some embodiments, the wireless device 106 (which may be an exemplary implementation of the device 100) may be configured to perform methods for robust discovery of new access point (AP) MLDs, robust link addition to AP MLD associations, AP beacon mode when an AP is added to or deleted from an AP MLD, and robust BSS transition management (BTM) signaling for directing non-AP MLDs to the best AP MLD and the most appropriate AP, and privacy improvements for associated non-AP MLDs.

[0115] Figure 4 —Access Point Block Diagram

[0116] Figure 4 An exemplary block diagram of an access point (AP) 112 is shown, which may be Figure 4 A possible exemplary implementation of the device 100 is shown. Note that Figure 4 The block diagram of the AP 112 is only one example of a possible system. As shown, the AP 112 may include one or more processors 204 that may execute program instructions for the AP 112. The processor 204 may also be coupled (directly or indirectly) to a memory management unit (MMU) 240 or other circuit or device, which may be configured to receive addresses from the processor 204 and convert these addresses to locations in memory (e.g., memory 260 and read-only memory (ROM) 250).

[0117] AP 112 may include at least one network port 270. Network port 270 may be configured to couple to a wired network and provide access to the Internet for multiple devices, such as mobile device 106. For example, network port 270 (and / or additional network ports) may be configured to couple to a local network, such as a home network or an enterprise network. For example, port 270 may be an Ethernet port. The local network may provide a connection to an additional network, such as the Internet.

[0118] The AP 112 may include at least one antenna 234, which may be configured to operate as a wireless transceiver and may be further configured to communicate with the mobile device 106 via the wireless communication circuit 230. The antenna 234 communicates with the wireless communication circuit 230 via the communication chain 232. The communication chain 232 may include one or more receive chains, one or more transmit chains, or both. The wireless communication circuit 230 may be configured to communicate via Wi-Fi or WLAN (e.g., 802.11). For example, when the AP is co-located with the base station in the case of a small cell, or in other situations where it may be desirable for the AP 112 to communicate via a variety of different wireless communication technologies, the wireless communication circuit 230 may also or alternatively be configured to communicate via various other wireless communication technologies, including, but not limited to, Long Term Evolution (LTE), Advanced LTE (LTE-A), 5G NR, UWB, etc.

[0119] Additionally, in some embodiments, as further described below, AP 112 may be configured to perform methods for robust discovery of new APs in access point (AP) MLDs, robust link addition to AP MLD associations, AP beacon mode when APs are added to or deleted from an AP MLD, and robust BSS transition management (BTM) signaling for directing non-AP MLDs to the best APMLD and most appropriate AP, and privacy improvements for associated non-AP MLDs.

[0120] Figure 5 —Client site diagram

[0121] Figure 5 An example simplified block diagram of a client station 106 is illustrated, which may be Figure 4A possible exemplary implementation of the device 100 shown. According to various embodiments, the client site 106 may be a user equipment (UE) device, a mobile device or mobile station and / or a wireless device or wireless station. As shown, the client site 106 may include a system on a chip (SOC) 300, which may include parts for various purposes. The SOC 300 may be coupled to various other circuits of the client site 106. For example, the client site 106 may include various types of memory (e.g., including NAND flash memory 310), a connector interface (I / F) (and / or dock) 320 (e.g., for coupling to a computer system, a docking station, a charging station, etc.), a display 360, cellular communication circuits (e.g., cellular radio components) 330 (such as for 5G NR, LTE, etc.), and medium- and short-range wireless communication circuits (e.g., Bluetooth TM and WLAN radio components) 329 (e.g., Bluetooth TM The client site 106 may further include one or more smart cards 315 incorporating SIM (Subscriber Identity Module) functionality, such as one or more UICCs (one or more Universal Integrated Circuit Cards). The cellular communication circuit 330 may be coupled to one or more antennas, such as antennas 335 and 336 as shown. The short-range to medium-range wireless communication circuit 329 may also be coupled to one or more antennas, such as antennas 337 and 338 as shown. Alternatively, in addition to or in lieu of being coupled to antennas 337 and 338, the short-range to medium-range wireless communication circuit 329 may be coupled to antennas 335 and 336. The short-range to medium-range wireless communication circuit 329 may include multiple receive chains and / or multiple transmit chains for receiving and / or transmitting multiple spatial streams in a configuration such as multiple input multiple output (MIMO). Some or all of the components of the short- and medium-range wireless communication circuit 329 and / or the cellular communication circuit 330 may be used for ranging communication, for example, ranging communication using WLAN communication, Bluetooth communication, and / or cellular communication.

[0122] As shown, the SOC 300 may include a processor 302 that may execute program instructions for the client station 106 and a display circuit 304 that may perform graphics processing and provide display signals to a display 360. The SOC 300 may also include a motion sensing circuit 370 that may detect motion of the client station 106, for example, using any of a gyroscope, an accelerometer, and / or various other motion sensing components. The one or more processors 302 may also be coupled to a memory management unit (MMU) 340 and / or other circuits or devices (such as the display circuit 304, the cellular communication circuit 330, the short-range wireless communication circuit 329, the connector interface (I / F) 320, and / or the display 360), which may be configured to receive addresses from the one or more processors 302 and convert those addresses to locations in a memory (e.g., the memory 306, the read-only memory (ROM) 350, the NAND flash memory 310). The MMU 340 may be configured to perform memory protection and page table translation or setup. In some embodiments, MMU 340 may be included as part of processor 302 .

[0123] As described above, the client station 106 may be configured to communicate directly with one or more neighboring client stations wirelessly. The client station 106 may be configured to communicate according to the WLAN RAT to enable communication in environments such as Figure 3 WLAN network communication as shown in Figure 1 The ranging shown in .

[0124] As described herein, the client site 106 may include hardware and software components for implementing the features described herein. For example, the processor 302 of the client site 106 may be configured to implement some or all of the features described herein, for example by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium). Alternatively (and / or in addition), the processor 302 may be configured as a programmable hardware element, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). Alternatively (and / or in addition), in combination with one or more of the other components 300, 304, 306, 310, 315, 320, 329, 330, 335, 336, 337, 338, 340, 350, 360, 370, the processor 302 of the UE 106 may be configured to implement some or all of the features described herein.

[0125] Furthermore, as described herein, processor 302 may include one or more processing elements. Thus, processor 302 may include one or more integrated circuits (ICs) configured to perform the functions of processor 302. Furthermore, each integrated circuit may include circuits (e.g., a first circuit, a second circuit, etc.) configured to perform the functions of processor 204.

[0126] In addition, as described herein, the cellular communication circuit 330 and the short-range wireless communication circuit 329 may each include one or more processing elements. In other words, one or more processing elements may be included in the cellular communication circuit 330 and may also be included in the short-range wireless communication circuit 329. Therefore, each of the cellular communication circuit 330 and the short-range wireless communication circuit 329 may include one or more integrated circuits (ICs) configured to perform the functions of the cellular communication circuit 330 and the short-range wireless communication circuit 329, respectively. In addition, each integrated circuit may include circuits (e.g., first circuits, second circuits, etc.) configured to perform the functions of the cellular communication circuit 330 and the short-range wireless communication circuit 329.

[0127] Figure 6 —Wireless Node Block Diagram

[0128] Figure 6 A possible block diagram of a wireless node 107 is shown. The wireless node may be Figure 6 . As shown, the wireless node 107 may include a system on a chip (SOC) 400, which may include parts for various purposes. For example, as shown, the SOC 400 may include one or more processors 402 that may execute program instructions for the wireless node 107 and a display circuit 404 that may perform graphics processing and provide display signals to a display 460. The SOC 400 may also include a motion sensing circuit 470, which may detect the motion of the wireless node 107, for example, using any of a gyroscope, an accelerometer, and / or various other motion sensing components. The one or more processors 402 may also be coupled to a memory management unit (MMU) 440, which may be configured to receive addresses from the one or more processors 402 and convert these addresses to locations in a memory (e.g., a memory 406 and a read-only memory (ROM) 450, a flash memory 410). The MMU 440 may be configured to perform memory protection and page table translation or setup. In some embodiments, MMU 440 may be included as part of processor 402 .

[0129] As shown, the SOC 400 may be coupled to various other circuits of the wireless node 107. For example, the wireless node 107 may include various types of memory (e.g., including NAND flash memory 410), a connector interface 420 (e.g., for coupling to a computer system, a docking station, a charging station, etc.), a display 460, and wireless communication circuitry 430 (e.g., for 5G NR, LTE, LTE-A, Bluetooth, Wi-Fi, NFC, UWB, etc.).

[0130] The wireless node 107 may include at least one antenna, and in some embodiments, may include multiple antennas 435 and 436 for performing wireless communications with base stations and / or other devices. For example, the wireless node 107 may perform wireless communications using antennas 435 and 436. As described above, the wireless node 107 may be configured in some embodiments to perform wireless communications using multiple wireless communication standards or radio access technologies (RATs).

[0131] Wireless communication circuitry 430 may include Wi-Fi logic 432, cellular modem 434, and Bluetooth logic 439. Wi-Fi logic 432 is used to enable wireless node 107 to perform Wi-Fi communications over, for example, an 802.11 network. Bluetooth logic 439 is used to enable wireless node 107 to perform Bluetooth communications. Cellular modem 434 may be capable of performing cellular communications according to one or more cellular communication technologies. Some or all of wireless communication circuitry 430 may be used for ranging communications, for example, using WLAN communications, Bluetooth communications, and / or cellular communications.

[0132] As described herein, the wireless node 107 may include hardware components and software components for implementing embodiments of the present disclosure. For example, one or more components of the wireless communication circuitry 430 (e.g., Wi-Fi logic component 432) of the wireless node 107 may be configured to implement part or all of the methods described herein, for example, by executing program instructions stored on a memory medium (e.g., a non-transitory computer-readable memory medium), a processor configured as an FPGA (field programmable gate array), and / or using dedicated hardware components that may include an ASIC (application-specific integrated circuit).

[0133] Figures 7 and 8 —Multi-Link Device (MLD) Operation

[0134] One or more IEEE 802.11 versions, such as IEEE 802.11bi, may include multi-link device (MLD) capabilities. In the current implementation, an access point (AP) multi-link device (MLD) node may manage its subordinate APs. Thus, the APMLD node may modify, add, and / or remove subordinate APs to increase capacity, manage basic service set (BSS) interference and coverage, including switching APs to operate in channels with less interference, and / or manipulate associated non-AP MLD nodes to operate on better performing APs and / or AP MLD nodes.

[0135] Figure 7 An AP MLD 112 is shown according to some embodiments. The AP MLD may operate any number of subordinate APs, such as APs 712a, 712b, 712c, and 712d in the illustrated example. The subordinate APs may operate on any of a variety of frequency bands. The subordinate APs may operate on different frequency ranges (e.g., channels) of the same frequency band or on different frequency bands.

[0136] The AP MLD may provide accessory APs from a single physical device (e.g., a single shared housing, and potentially using the same antennas). In some embodiments, the AP MLD may provide APs from multiple different devices (e.g., a first device may provide one or more APs, a second device may provide a different one or more APs, etc.). In some embodiments, the various accessory APs may be spatially separated (e.g., using beams in different directions, using different antennas with a shared housing (e.g., antennas of the same physical device) and / or different antennas for different devices, etc.).

[0137] In some embodiments, spatially separated subsidiary APs may operate on the same (or overlapping) channels.

[0138] Figure 8 AP MLD 112 is shown communicating with non-AP MLD 106 according to some embodiments.

[0139] As shown, AP MLD 112 can operate three subordinate APs. In the illustrated example, AP 812a can operate in the 2.4 GHz band, AP 812b can operate in the 5 GHz band, and AP 812c can operate in the 6 GHz band. It should be understood that any number of subordinate APs can be used in any combination of frequency bands. For example, the AP MLD can operate multiple subordinate APs in one frequency band and / or it is possible not to operate any subordinate AP in the frequency band. The subordinate APs can include various layers, such as a medium access control (MAC) and / or a physical (PHY) layer and various possibilities. The subordinate APs can use different basic service sets (BSSs) and / or different BSS identifiers (BSSIDs), such as BSSID 1 to BSSID 3.

[0140] As shown, the non-AP MLD 106 may operate, for example, three subordinate STAs corresponding to three subordinate APs. In the illustrated example, STA 806a may operate in the 2.4 GHz band, STA 806b may operate in the 5 GHz band, and STA 806c may operate in the 6 GHz band. The STA may communicate with the corresponding AP. It should be understood that any number of subordinate STAs may be used in any combination of frequency bands. For example, the non-AP MLD may operate multiple subordinate STAs in one frequency band and / or it may not operate any subordinate STA in the frequency band. The non-AP MLD may operate STAs corresponding to some or all of the APs of the AP MLD, or STAs that do not correspond to the AP MLD. The subordinate STA may include various layers, for example, PHY and / or MAC layers and various possibilities. The subordinate STA may use different addresses, for example, address 1 to address 3.

[0141] A non-AP MLD may provide attached STAs from a single physical device (e.g., a single shared housing, and potentially using the same antenna). In some embodiments, a non-AP MLD may provide STAs from multiple different devices (e.g., a first device may provide one or more STAs, a second device may provide a different one or more STAs, etc.). In some embodiments, the various attached STAs may be spatially separated (e.g., using beams in different directions, using different antennas with a shared housing (e.g., antennas of the same physical device) and / or different antennas of different devices, etc.).

[0142] Various affiliated STAs and APs may communicate concurrently / simultaneously. For example, STA 806a may exchange uplink data and / or downlink data with AP 812a on a first link, while STA 806b may exchange uplink data and / or downlink data with AP 812b on a second link, and so on. It should be understood that such concurrent communications may include exchanging (e.g., different) data on different links at the same time, overlapping times, and / or different times. For example, data between an AP MLD and a non-AP MLD may be routed via a first available link and / or a link selected based on other criteria (e.g., minimum energy usage, etc.). For example, a first packet or portion of data may be transmitted via a first link, and concurrently, a second packet or portion of data may be transmitted via a second link.

[0143] In some embodiments, the AP MLD and the non-AP MLD may include a corresponding ML entity. The ML entity may provide upper layer MAC functionality to control individual APs and / or STAs, and may control the delivery of traffic over available links between, for example, various APs and STAs. A corresponding MLD (e.g., AP and non-AP) may have only one corresponding MAC SAP interface. The ML entity may manage the interface. The ML entity may manage the transmit buffering (e.g., bookkeeping and link selection in the sender) and the data reordering buffering in the receive (e.g., the combination of data sent in different links).

[0144] The AP MLD 112 and the non-AP MLD 106 may exchange information regarding their respective operations, operating parameters, and / or capabilities.

[0145] The non-AP MLD may have various capabilities for operating a STA in a specific frequency band. The capabilities may be different for different frequency bands. For example, the capabilities in a frequency band may describe the maximum (e.g., fastest, most flexible, most powerful, highest throughput, etc.) parameter values ​​that a STA of the non-AP MLD can use. Operations or operation parameters may describe parameter values ​​that are currently used or planned to be used at a future time.

[0146] For example, the parameter may include the applicable PHY version and its parameters. The parameter may describe the available supported services and transmission formats. The parameter may also describe the available resources, bandwidth, and number of spatial streams. The parameter may describe power saving support parameters that may enable low power transmission. For example, the AP may support target wake time (TWT) power saving.

[0147] In some embodiments, the links may be located too close together (e.g., spatially and / or in frequency) so that the non-AP STAs may not be able to operate the links independently (e.g., due to device limitations and / or to manage resources or performance). The AP may support STAs that are not able to transmit and receive simultaneously on a link pair (e.g., non-AP MLDs).

[0148] In some embodiments, a non-AP MLD may operate a STA that communicates with multiple AP-MLDs. For example, a first STA may communicate with a first AP MLD, and a second STA may communicate with a second AP MLD. Similarly, an AP MLD may communicate with multiple STAs. For example, one subordinate AP may communicate with multiple STAs.

[0149] In the illustrated example, the non-AP MLD operates a number of STAs equal to the number of APs provided by the AP MLD. However, different numbers are possible. For example, the AP MLD may provide more APs than the number of STAs operated by the non-AP MLD, or vice versa. The number of APs and / or the number of STAs may change over time.

[0150] According to some embodiments, it may be beneficial for a client privacy enhancement (CPE) station (STA) or client to change or adjust certain parameters used to perform communications with an AP. For example, an eavesdropper may attempt to intercept, extract, or listen to certain communications between a CPE STA and an AP. Therefore, the client may attempt to use various techniques involving address changes or related parameter adjustments to perform more secure communications between a CPE STA and an AP.

[0151] For example, when reassociating from one CPE AP to another, it may be beneficial for the CPE client to change its own over-the-air (OTA) media access control (MAC) address used to communicate with the AP. Additionally or alternatively, it may be beneficial for the CPE client to initiate a change to its own OTA MAC address used with the CPE AP in an associated state (e.g., STA state 4) without any connection loss. In some embodiments, it may be beneficial for the CPE client to simultaneously initiate a change to the OTA MAC address of all associated CPE clients (e.g., those CPE clients in associated STA state 4) in a base station system (BSS) without any connection loss. In addition, according to some embodiments, it may be beneficial for the CPE client and the CPE AP to change the sent sequence number (SN), packet number (PN), and transaction identifier (TID) to unrelated new values ​​on the downlink and uplink, new values ​​in associated STA state 4 without any connection loss. In addition, it may be further beneficial for the CPE client and the CPE AP to change the association identifier (AID) of the CPE client to an unrelated new value in associated STA state 4 without any connection loss.

[0152] Enhanced coordinated channel access in wireless networking systems

[0153] Channel access delay can be considered as one of the main sources of latency, and therefore can significantly affect situations involving low latency between STAs and APs. For example, according to some embodiments, a STA competes with other STAs (including APs) in the BSS (and OBSS) to obtain channel access. In addition, UL-triggered channel access relies on the AP to obtain access to the channel and the AP to schedule UL traffic. Therefore, as an example, WLAN channel access may be particularly inefficient when many users compete for short transmissions. In this scenario, the channel may be segmented and conflicts may occur occasionally. In addition, according to some embodiments, short TXOPs may result in inefficient use of channels, while long TXOPs may increase latency for other users to access the channel.

[0154] FIG. 9A to FIG. 9B - Channel access contention

[0155] FIG. 9A to FIG. 9B Various example aspects of channel access contention between devices according to some embodiments are illustrated. For example, Fig.9A The present invention illustrates a scenario involving uplink (UL) enhanced distributed channel access (EDCA) delays that may occur when a STA is competing with other STAs in the same BSS and due to AP traffic and OBSS traffic. More specifically, Fig.9A Four STAs (STA 1 to STA 4) are illustrated trying to access the channel in such an environment. Fig.9A As shown in , STA 1 may gain access to the channel after the backoff counter has expired and continue to send data (e.g., UL data to the AP or P2P data to the STA). Therefore, according to some embodiments, when STA 1 is sending the data, STA 2 to STA 3 may be considered busy. Then, STA 2 may subsequently gain access to the channel and send its data. However, due to OBSS traffic and traffic of other STAs (e.g., manufacturers different from those of STA 1 to STA 4) in the channel, STA 3 and STA 4 may experience additional longer periods (during which they are busy), which ultimately results in longer channel access delays. In addition, according to some embodiments, in such a congested environment, the probability of accessing the channel decreases as the number of STAs increases.

[0156] Fig. 9B FIG9A illustrates a scenario involving UL TXOP sharing and delay that may occur when a STA competes with other STAs in the same BSS and due to AP traffic and OBSS traffic. More specifically, Fig. 9BFour STAs (STA 1 to STA 4) are illustrated, and these four STAs can form a group because they share the same or similar manufacturer, and further coordinate with each other to access the channel. Fig. 9B 1 to STA 4), the STA may be the TXOP holder and share the TXOP with other STAs in the same group (e.g., STA 2 to STA 4). Therefore, after each STA transmission, the TXOP may be shared with the next STA in the group. Additionally, due to OBSS traffic in the channel and traffic from other STAs (e.g., manufacturers different from those of STA 1 to STA 4), the group of STAs may all experience additional longer periods during which they are busy. Furthermore, after another round of contention, STA 2 may first gain access to the channel (e.g., be the TXOP holder) and may then share the TXOP with STA 3, STA 4, and STA 1, respectively. Fig. 9B It is illustrated that the probability of accessing the channel increases as the number of STAs in the coordination group increases. However, according to some embodiments, the TXOP duration shared in the STA group may decrease as the number of STAs in the coordination group increases.

[0157] In some cases, it may be necessary to periodically send a small amount of traffic by multiple STAs. For example, multiple STAs may compete to share a TXOP between them. More specifically, according to some embodiments, in infra-UL boost, multiple STAs may compete to increase the probability of accessing a channel. Additionally, according to some embodiments, P2P example communications may include periodically accessing a channel at a fast pace to send a small amount of data.

[0158] Furthermore, according to some embodiments, multiple STAs may compete on behalf of other STAs. Alternatively, according to some embodiments, some STAs may compete for channels to help one (or more) users (eg, other STAs) improve their services.

[0159] FIG. 10A to FIG. 10C —Send opportunity sharing

[0160] FIG. 10A to FIG. 10C Various example aspects of transmit opportunity (TXOP) sharing according to some embodiments are illustrated. For example, according to some embodiments, although TXOP sharing may not increase the probability of a group of STAs accessing a channel, it can increase the efficiency of using the channel and sharing the channel with the group so that when the STAs have data to send, they can compete for channel access.

[0161] FIG. 10A to FIG. 10C Different examples of TXOP sharing involving four STAs (STA 1 to STA 4) are illustrated. For example, Fig. 10AA full buffer scenario is illustrated, where if there is no sharing, STA 1 to STA 4 can send their data in a separate TXOP and can utilize the full buffer (e.g., the entire TXOP). Alternatively, if the STAs are sharing a TXOP, STA 1 to STA 4 can use the medium (e.g., TXOP) in the same manner, except that the resources are redistributed among the group members (e.g., STA 1 to STA 4). In other words, according to some embodiments, STA 1 to STA 4 can transmit across the full buffer (e.g., TXOP) but using an equal amount of resources distributed for each STA to transmit.

[0162] Fig. 10B A non-full buffer scenario is illustrated, where if there is no sharing, the STAs can send data individually in different TXOPs and do not utilize the full buffer. Alternatively, according to some embodiments, if STA 1 to STA 4 are sharing a TXOP, STA 1 to STA 4 can use the medium more efficiently, where the TXOP is extended to allow other STAs to reuse it.

[0163] Alternatively, Fig. 10C A scenario involving mixed TXOP sharing and legacy equipment is illustrated. More specifically, according to some embodiments, although STA 1 and STA 3 may share a common manufacturer, STA 2 and STA 4 may be manufactured by different entities (or multiple entities) other than the manufacturers of STA 1 and STA 3. For example, if there is no sharing, STA 1 to STA 4 may send their data in a separate TXOP and may utilize a full buffer (e.g., the entire TXOP). Alternatively, if there is mixed sharing, STA 1 to STA 4 may share the medium by redistributing their resources among other STAs in the same group. For example, according to some embodiments, STA 1 and STA 3 may redistribute their resources to share the TXOP because they may share common capabilities and / or components (due to being manufactured by the same manufacturer). In addition, according to some embodiments, STA 1 and STA 3 may also be configured to be different from the configuration of STA 2 and STA 4, and they may all be from the same manufacturer.

[0164] Fig.11 —Send opportunity sharing group

[0165] Fig.11Various example aspects of TXOP sharing groups according to some embodiments are illustrated. For example, according to some embodiments, a TXOP sharing group may be formed by a STA that initiates a protocol to discover an available group. Thus, if an available group is found, the STA may join the group. Alternatively, according to some embodiments, if no group or available group is found, the STA may create a new group including itself. Once a STA joins a TXOP sharing group, the STA may receive a group scheduling plan and sharing rules, including a cadence and a sharing quota (as some examples).

[0166] Furthermore, a neighborhood area network (NAN) or any other higher layer application may be used to assist in the process or task of joining or creating a TXOP sharing group. Additionally, according to some embodiments, maintaining, terminating, or updating TXOP sharing group parameters may be facilitated via the use of a NAN.

[0167] In some cases, coordinating channel access may include providing a cadence for accessing the channel to group members, and each user shares the cadence upon joining or upon any update. In other words, the cadence of channel access may be shared upon joining (NAN) or by updating. In some embodiments, any access beyond this cadence may not be covered by sharing. Therefore, all group members may begin competing for channel access at the scheduled time. Additionally, once the channel is accessed by one of these members, the TXOP may be shared by the TXOP holder among the TXOP sharing group members.

[0168] According to some embodiments, in order to share a TXOP between STAs in a TXOP sharing group, a TXOP holder may use a portion of the TXOP and release the remaining portion to other STAs in the group. Additionally, according to some embodiments, if the amount of resources required is less than the scheduled resources or if the resources are not required (e.g., the STA has no data to send), the STA may release the resources.

[0169] In some embodiments, the STAs in a group may ideally be located close together to see the same state of the channel (e.g., busy / ideal). In addition, due to the fact that increasing the number of STAs in a group increases the probability of accessing the channel and also increases the probability of collisions, the number of STAs in the group should ideally be balanced.

[0170] In some embodiments, a sharing group may be formed using higher layer formation criteria (devices sharing the same manufacturer ID at the same network). In addition, a TXOP sharing group may be formed in an opportunistic manner (e.g., when other users or STAs are willing to coordinate). For example, according to some embodiments, it may be possible to reuse the WiFi-NAN protocol to form a group.

[0171] For example, Fig.11An example of a TXOP sharing group (e.g., group A) including STA 1 to STA 3 (and possibly more STAs) that contend with the AP for channel access every "x" seconds (e.g., contend for channel access according to a configured cadence) is illustrated. In addition, STA 1 may first gain access to the channel (e.g., win the TXOP). Therefore, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send data communications to the AP (or to other STAs via P2P communications). Therefore, after completing its data transmission, STA 1 may release the remainder of the TXOP to STA 2 and STA 3 so that they may also perform data transmission during the TXOP.

[0172] In addition, after another round of contention, STA 3 may first obtain access to the channel (e.g., win the TXOP). Therefore, STA 3 may become the TXOP holder, and may therefore access and utilize the channel to send data communications to the AP (or to other STAs via P2P communication). Therefore, after completing its data transmission, STA 3 may release the remainder of the TXOP to STA 1 and STA 2, so that they may also perform data transmission during the TXOP. After another round of contention, STA 2 may first obtain access to the channel and become the TXOP holder. Therefore, STA 2 may access and utilize the channel to send data communications to the AP (or to other STAs via P2P communication). Therefore, according to some embodiments, after completing its data transmission, STA 2 may release the remainder of the TXOP to STA 3 and STA 1, so that they may also perform data transmission during the TXOP.

[0173] Therefore, according to some embodiments, there may be a motivation for STAs to coordinate with other STAs or APs to obtain channel access (compared to OBSS STAs and non-cooperative STAs). For example, devices made by the same (or similar) manufacturer may be able to coordinate with each other to obtain lower channel access latency. More specifically, in order to improve channel access latency for devices that share common capabilities and components (e.g., due to sharing the same or similar manufacturers), it may be beneficial for such STAs to form one or more groups to coordinate channel access. Therefore, according to some embodiments, when a STA is able to access a channel, the STA (or AP) may be able to more efficiently coordinate the distribution of TXOP resources with other STAs in the same group.

[0174] Fig.12 —Example method for enhanced STA coordinated channel access

[0175] Fig.12 is a communication flow diagram illustrating an example method of enhanced STA coordinated channel access according to some embodiments. More specifically, Fig.12Embodiments of systems, methods, and mechanisms for non-APs to coordinate with other non-APs to more efficiently use transmit opportunities (TXOPs) are illustrated. Such techniques may help reduce latency and / or reduce power consumption.

[0176] Fig.12 Aspects of the method may be implemented by a non-AP (or non-AP MLD) communicating with an AP MLD (or non-MLD AP) and one or more other non-APs. The AP and / or non-AP may be illustrated and described as in the various figures herein, or more generally, may be illustrated and described in conjunction with any of the computer circuits, systems, devices, elements, or components shown in the above figures as needed. For example, a processor (and / or other hardware) of such a device may be configured to cause the device to perform any combination of the illustrated method elements and / or other method elements. For example, one or more processors (or processing elements) (e.g., processors 101, 204, 302, 402, 432, 434, 439, baseband processors, processors associated with communication circuits such as 130, 230, 232, 329, 330, 430, and various possibilities) may cause a wireless device, STA, UE, non-AP, and / or AP or other device to perform such method elements.

[0177] Note that although described in terms of using communication techniques and / or features associated with IEEE and / or 802.11 (e.g., 802.11be) specification documents, Fig.12 but such description is not intended to limit the present disclosure, and Fig.12 Various aspects of the method may be used in any suitable wireless communication system as desired. Similarly, although described in terms of being related to a non-AP that may not be an MLD Fig.12 However, such description is not intended to limit the present disclosure, and Fig.12 Aspects of the method may be used by a non-AP (which is an MLD) as desired.

[0178] In addition to other devices, the method shown can also be used with any one of the systems, methods or devices shown in the accompanying drawings. In various embodiments, some of the method elements shown can be performed concurrently in an order different from the order shown, or can be omitted. Additional method elements can also be performed as needed. As shown in the figure, the method can be operated as follows.

[0179] In 1202, according to some embodiments, the first non-AP 106A may receive information corresponding to the TXOP from the second non-AP. More specifically, the first non-AP belonging to a group of at least two non-APs may receive signaling including information corresponding to the TXOP from the second non-AP in the group of at least two non-APs. For example, according to some embodiments, the first non-AP and the second non-AP (106A and 106B) may be grouped in a TXOP sharing group. Therefore, no matter which non-AP in the TXOP sharing group obtains access to the channel, the non-AP may be considered a TXOP winner. In addition, according to some embodiments, the TXOP winner may send signaling to another non-AP in the TXOP sharing group in order to share the TXOP and make the other non-AP of the TXOP sharing group a TXOP beneficiary. For example, in 1202, the second non-AP 106B of the TXOP group may be the TXOP winner, and may then transmit information signaling to the first non-AP 106A, so that the first non-AP 106A becomes the TXOP beneficiary and can use the TXOP to send data to one or more devices.

[0180] In some embodiments, the signaling may include information indicating that the first non-AP is to use only at least a portion of the TXOP to transmit data to the one or more devices. Additionally, according to some embodiments, if the first non-AP completes the transmission of the first data to the one or more devices before the end of the TXOP, the first non-AP may send a clear to transmit (CTS) message including one or more parameters to the group address of the group of at least two non-APs to terminate the TXOP.

[0181] According to some embodiments, the first non-AP may send one or more multi-user block acknowledgement requests (MU-BARs) to the at least two non-APs, and receive one or more block acknowledgements (BAs) from the at least two non-APs. Additionally or alternatively, the signaling including information corresponding to a transmit opportunity (TXOP) may be a clear to transmit (CTS) message including addresses of the group of at least two non-APs. Furthermore, the signaling may be performed after one or more contention periods have elapsed. Fig.12 method.

[0182] In some embodiments, the signaling may include information indicating that the first non-AP and one or more other non-APs in the group of at least two non-APs are caused to respectively transmit data to one or more devices using at least a portion of the TXOP. In addition, if one of the at least two non-APs completes the corresponding data transmission to the one or more devices before the end of the TXOP, the first non-AP may further receive a clear to transmit (CTS) message including one or more parameters at the group address of the group of at least two non-APs to terminate the TXOP.

[0183] In 1204, according to some embodiments, the first non-AP may use the TXOP to send data. More specifically, the first non-AP may send first data to one or more devices based on information corresponding to the TXOP and scheduling information of the group of at least two non-APs, wherein the first data is sent to the one or more devices in at least a portion of the TXOP. For example, according to some embodiments, after having received information about the TXOP and becoming a TXOP beneficiary in 1202, the first non-AP may continue to use the TXOP to send data (e.g., send UL data to the AP or send P2P data to other non-APs).

[0184] According to further embodiments, the group of at least two non-APs may be associated with a group address or a group identifier (ID). Additionally or alternatively, the one or more devices may include at least one of the following: one or more APs, one or more mobile APs, one or more non-APs, or one or more non-AP stations (STAs).

[0185] Fig.13 — Additional method for enhanced STA coordinated channel access

[0186] Fig.13 is a communication flow diagram illustrating an example method for coordinating channel access by STAs according to some embodiments. More specifically, Fig.13 Embodiments of systems, methods, and mechanisms for non-APs to coordinate with other non-APs and APs to more efficiently use transmit opportunities (TXOPs) are illustrated. Such techniques may help reduce latency and / or reduce power consumption.

[0187] Fig.13 Aspects of the method may be implemented by a non-AP (or non-AP MLD) communicating with an AP MLD (or non-MLD AP) and one or more other non-APs. The AP and / or non-AP may be illustrated and described as in the various figures herein, or more generally, may be illustrated and described in conjunction with any of the computer circuits, systems, devices, elements, or components shown in the above figures as needed. For example, a processor (and / or other hardware) of such a device may be configured to cause the device to perform any combination of the illustrated method elements and / or other method elements. For example, one or more processors (or processing elements) (e.g., processors 101, 204, 302, 402, 432, 434, 439, baseband processors, processors associated with communication circuits such as 130, 230, 232, 329, 330, 430, and various possibilities) may cause a wireless device, STA, UE, non-AP, and / or AP or other device to perform such method elements.

[0188] Note that although described in terms of using communication techniques and / or features associated with IEEE and / or 802.11 (e.g., 802.11be) specification documents, Fig.13 but such description is not intended to limit the present disclosure, and Fig.13 Various aspects of the method may be used in any suitable wireless communication system as desired. Similarly, although described in terms of being related to a non-AP that may not be an MLD Fig.13 However, such description is not intended to limit the present disclosure, and Fig.13 Aspects of the method may be used by a non-AP (which is an MLD) as desired.

[0189] In addition to other devices, the method shown can also be used with any one of the systems, methods or devices shown in the accompanying drawings. In various embodiments, some of the method elements shown can be performed concurrently in an order different from the order shown, or can be omitted. Additional method elements can also be performed as needed. As shown in the figure, the method can be operated as follows.

[0190] At 1302, according to some embodiments, the first non-AP 106A may establish a link with the AP 112. More specifically, at 1302, the first non-AP 106A may establish a wireless link with the AP 112 via an access channel. For example, the first non-AP 106A in the TXOP sharing group may be the first non-AP in the group to gain access to the channel via establishing a link with the AP 112. Thus, the first non-AP 106 may be considered a TXOP winner.

[0191] In 1304, according to some embodiments, the first non-AP 106A may send a request with the group address to the AP 112. More specifically, at 1304, the first non-AP 106A may send a request corresponding to the TXOP and including the addresses of the group of at least two non-APs to the AP 112. In some embodiments, the request may include an indication that only one of the at least two non-APs is to use at least a portion of the TXOP to send data to the one or more devices. In 1306, according to some embodiments, the AP 112 may send a response to the first non-AP 106A. For example, the response may be a clear to send (CTS) message indicating to the first non-AP 106A that it may send data.

[0192] In 1308, according to some embodiments, the first non-AP 106A may use the TXOP to send data. More specifically, at 1308, the first non-AP 106A may send data to the one or more devices according to the scheduling information of the group of at least two non-APs, wherein the first data is sent to the one or more devices in at least a portion of the TXOP.

[0193] According to some embodiments, if the first non-AP completes transmission of the first data to the one or more devices before the TXOP ends, the first non-AP 106A may broadcast one or more invitation to send (ITS) messages to the group address of the at least two non-APs in the group. Additionally or alternatively, the first non-AP 106A may receive one or more invitation to send (ITS) messages from one or more non-APs of the at least two non-APs. Furthermore, the one or more ITS messages may indicate to the first non-AP that the non-AP has no data to send or that the non-AP has completed transmission of data to the one or more devices before a portion of the TXOP ends.

[0194] Fig.14 — Example method for enhanced AP coordinated channel access

[0195] As previously discussed, according to some embodiments, channel access delay may be considered one of the main sources of latency due to a STA competing with other STAs (including APs) in the BSS (and OBSS) to gain channel access.

[0196] However, most low-latency UL applications may not have high data rate requirements for each channel access. Therefore, it may be beneficial for the AP to help coordinate the sharing of one TXOP between multiple APs or multiple STAs in the time domain and frequency domain to support low-latency applications. For example, although STAs may coordinate with each other to obtain channel access (compared to OBSS STAs and non-cooperative STAs), it is possible for the AP to help or enhance the coordination to better or more efficiently and flexibly distribute resources among a group of devices. For example, if STAs form a group to coordinate channel access, once the STA of the group accesses the channel, the STA can use the AP to help trigger other members of the group. Therefore, such enhanced coordination can improve the channel access latency of P2P devices or UL devices.

[0197] For example, it is possible that the AP helps coordinate TXOP sharing between STAs in a group, because it may be expected that the AP will implement TXOP sharing between other APs. Therefore, the tool may already be reused for triggered TXOP sharing (e.g., TXS). Therefore, according to some embodiments, a STA interested in sharing its TXOP for a group may use a group address to indicate the interest. Therefore, any STA in the group list that accesses the channel can share the TXOP with the AP. The AP can then manage the sharing of the TXOP between the STAs in the group. In some cases, according to some embodiments, the AP may share the TXOP only with a predefined group of STAs in the TXOP sharing group. For example, according to some embodiments, the AP may manage the sharing of the TXOP between a group of stays in a manner similar to or via a predefined scheduling plan in time or frequency for reverse direction multi-user-multiple input and multiple output (RD UL MU-MIMO). In addition, according to some embodiments, the STA may have a use case in which multiple STAs need to access the channel using the same rhythm (live P2P session, visual audio, etc.). Therefore, by sharing TXOPs between STAs and APs, it is possible for the AP to better coordinate channel access without imposing power constraints on STAs.

[0198] Fig.14 is a communication flow diagram illustrating an example method of enhanced AP coordinated channel access according to some embodiments. More specifically, Fig.14 Embodiments of systems, methods, and mechanisms for APs to coordinate with non-APs to more efficiently use transmit opportunities (TXOPs) are illustrated. Such techniques may help reduce latency and / or reduce power consumption.

[0199] Fig.14 Aspects of the method may be implemented by an AP (or AP MLD) communicating with one or more non-APs (or MLD non-APs). The AP and / or non-AP may be illustrated and described as in the various figures of this document, or more generally, may be illustrated and described in conjunction with any of the computer circuits, systems, devices, elements, or components shown in the above figures as needed. For example, a processor (and / or other hardware) of such a device may be configured to cause the device to perform any combination of the method elements shown and / or other method elements. For example, one or more processors (or processing elements) (e.g., processors 101, 204, 302, 402, 432, 434, 439, baseband processors, processors associated with communication circuits such as 130, 230, 232, 329, 330, 430, and various possibilities) may cause a wireless device, STA, UE, non-AP and / or AP or other device to perform such method elements.

[0200] Note that although described in terms of using communication techniques and / or features associated with IEEE and / or 802.11 (e.g., 802.11be) specification documents, Fig.14 but such description is not intended to limit the present disclosure, and Fig.14 Various aspects of the method may be used in any suitable wireless communication system as desired. Similarly, although described in terms of being related to a non-AP that may not be an MLD Fig.14 However, such description is not intended to limit the present disclosure, and Fig.14 Aspects of the method may be used by a non-AP (which is an MLD) as desired.

[0201] In addition to other devices, the method shown can also be used with any one of the systems, methods or devices shown in the accompanying drawings. In various embodiments, some of the method elements shown can be performed concurrently in an order different from the order shown, or can be omitted. Additional method elements can also be performed as needed. As shown in the figure, the method can be operated as follows.

[0202] At 1402, according to some embodiments, the first non-AP 106A may establish a link with the AP 112. More specifically, at 1402, the first non-AP 106A may establish a wireless link with the AP 112 via an access channel. For example, the first non-AP 106A in the TXOP sharing group may be the first non-AP in the group to gain access to the channel via establishing a link with the AP 112. Thus, the first non-AP 106 may be considered a TXOP winner.

[0203] In 1404, according to some embodiments, the first non-AP 106A may send a request with a group address to the AP 112. More specifically, at 1404, the first non-AP 106A may send a request corresponding to the TXOP and including a group of addresses of at least two non-APs to the AP 112. In some embodiments, the request may include an indication that only one of the at least two non-APs is to use at least a portion of the TXOP to send data to the one or more devices. In 1306, according to some embodiments, the AP 112 may send a response to the first non-AP 106A. For example, the response may be a clear to send (CTS) message indicating to the first non-AP 106A that it may send data.

[0204] At 1406, according to some embodiments, the AP 112 may send a response to the first non-AP 106A. More specifically, at 1406, the AP 112 may send a response including a TXOP sharing indication to the first non-AP 106A.

[0205] In accordance with some embodiments, the first non-AP 106A may transmit data using the TXOP at 1408. More specifically, at 1408, the first non-AP 106A may transmit data to one or more devices according to the scheduling information of the group of at least two non-APs, wherein the data is transmitted to the one or more devices in at least a portion of the TXOP.

[0206] At 1410, according to some embodiments, the non-AP or AP 112 may send a response to the second non-AP 106B. More specifically, at 1410, the AP 112 may send an additional response including a TXOP sharing indication to the second non-AP 106B.

[0207] Thus, at 1412, according to some embodiments, the second non-AP 106B may use the TXOP to send data. More specifically, at 1412, the second non-AP 106B may send data to one or more devices according to the scheduling information of the group of at least two non-APs, wherein the data is sent to the one or more devices in at least a portion of the TXOP.

[0208] According to some embodiments, AP 112 may send one or more null data packet feedback report polls (NFRPs) to one or more non-APs in the group of at least two non-APs. Additionally or alternatively, AP 112 may send one or more request to send (RTS) messages to one or more non-APs in the group of at least two non-APs, wherein the duration of the RTS message is the maximum shared duration allowed.

[0209] In some embodiments, AP 112 may receive one or more clear to send (CTS) messages from one or more non-APs in the group of at least two non-APs, wherein the duration of the CTS messages indicates that the requested duration is less than or equal to the allowed maximum shared duration. Additionally or alternatively, in response to one or more non-APs in the group of at least two non-APs completing transmission before the assigned time, AP 112 may perform point coordination function interframe space (PIFS) recovery of the access channel.

[0210] FIG. 15A to FIG. 24 — Example aspects of STA coordinated channel access

[0211] According to some embodiments, Figure 12 to Figure 13 The method can further correspond to FIG. 15A to FIG. 24 For example, FIG. 15A to FIG. 15EVarious examples of TXOP sharing scenarios among four STAs according to some embodiments are illustrated (e.g., without further coordination assistance from an AP), where a dedicated coordinator (e.g., one of the four STAs) may not be required to stay awake. Therefore, these scenarios and their STA coordination have the potential to not only reduce the complexity of TXOP sharing, but also further save power for STAs by not requiring one of the STAs to stay awake constantly.

[0212] More specifically, Fig.15A An example scenario is illustrated in which one of four STAs (e.g., STA 1) is promoted by other STAs in the group (e.g., STA 2 to STA 4) according to some embodiments. For example, after a backoff timer (which may specify a random time interval before retrying to access the channel), one of the STAs in the group may gain access to the channel. Therefore, the STA (e.g., STA 2) that first gains access to the channel may send a message (such as a Clear to Transmit (CTS) message) using the receive (RX) address of the STA to be promoted (e.g., STA 1) or using a group ID (e.g., an identifier of a group including STA 1 to STA 4) or using any other new control frame carrying the same information. Therefore, according to some embodiments, STA 1 may benefit from the promotion and may utilize the entire TXOP by sending data to the AP via uplink (UL) transmission or communicating with other STAs via point-to-point (P2P) communication. In addition, after STA 1 completes its transmission in the TXOP, the STAs in the group may utilize their backoff timers again before retrying to access the channel. For example, a STA in a channel may be considered busy (e.g., inaccessible) due to traffic from an overlapping basic service set (OBSS) or other STAs in the channel (e.g., STAs outside the group). However, once the channel becomes accessible again, the STAs in the group may attempt to access the channel again after their backoff timers have expired. For example, a different STA in the group (e.g., STA 4) may be granted access to the channel in the second channel access attempt from the group. Therefore, STA 4 may also promote STA 1 by sending a CTS or a new control frame so that STA 1 can access the channel and send communications (e.g., UL or P2P) during the TXOP. In other words, Fig.15A An example scenario is illustrated in accordance with some embodiments, where STAs in one group may promote one STA via transmitting a frame indicating that the STA should access a channel, such that the promoted STA gains access to the channel and is able to perform communications utilizing the TXOP.

[0213] Similar to Fig.15A , Fig. 15BAn alternative scenario according to some embodiments is illustrated, in which the STAs in the group (e.g., STA 1 to STA 4) may have a predefined or assigned scheduling plan to alternate the TXOP beneficiaries to be promoted. For example, the STA that first obtains access to the channel (e.g., STA 2) may be considered the TXOP winner, and may use the receive (RX) address of the STA to be promoted (e.g., STA 1) or use the group ID (e.g., the identifier of the group containing STA 1 to STA 4) or use any other new control frame carrying the same information to send a message (such as a CTS message). Therefore, STA 1 may be characterized as a TXOP beneficiary and further benefit from being promoted to transmit data using the full TXOP. However, at the second channel access attempt (after the busy period and backoff timer due to OBSS traffic / other STA traffic expires), a different STA in the group (e.g., STA 4) may be granted access to the channel. Therefore, STA 4 can promote the STA (eg, STA 2) that was not previously promoted by sending a CTS or a new control frame so that STA 2 can access the channel and send communications (eg, UL or P2P) during the TXOP. In other words, Fig. 15B A mechanism for alternately promoting a particular STA (e.g., being granted access to a channel to transmit during a TXOP) according to some embodiments is illustrated. FIG. 15A to FIG. 15B Example mechanisms for promoting channel access without sharing overhead and complexity are illustrated.

[0214] Fig. 15C An example scenario is illustrated in which STAs in a group may have a predefined or assigned scheduling plan to alternate the first TXOP STA to use the channel (e.g., utilize a portion of the shared TXOP) and then share the remaining duration of the TXOP with other STAs in the group. Fig. 15CIn the shared TXOP, STA 2 may obtain access to the channel after the backoff timer expires, and send a CTS or a new control frame according to a predefined or assigned scheduling plan, so that STA 1 can access the channel and perform UL transmission or P2P transmission using a portion of the shared TXOP. Therefore, according to some embodiments, after receiving the CTS from STA 2 (e.g., the STA-TXOP winner that initially obtains access to the channel), STA 1 may be considered a TXOP beneficiary and / or TXOP holder of the shared TXOP. In addition, once the TXOP holder (e.g., STA 1) has completed its transmission in the shared TXOP, the remaining STAs in the group (e.g., STA 2 to STA 4) may then sequentially (STA 2, STA 3 and then STA 4) send their UL communications or P2P communications for the remaining duration of the TXOP. Additionally, in the second channel access attempt (after the busy period and backoff timer due to OBSS traffic / other STA traffic expire), a different STA in the group (e.g., STA 3) may be granted access to the channel and send a CTS or a new control frame to reassign the TXOP TXOP holder (e.g., STA 2). Therefore, STA 2 may continue to perform UL communication or P2P communication during a portion of the TXOP, and then share the remaining duration of the shared TXOP with other STAs in the group. For example, STA 3, STA 4, and STA 1 may then send their UL signaling / P2P signaling, respectively, during the corresponding remaining portions of the shared TXOP. In other words, the TXOP winner (e.g., the STA that first obtains access to the channel) may decide or determine which STA to share the channel with (e.g., which STA to make the TXOP holder). Therefore, the TXOP holder may first perform its UL communication / P2P communication, and then the other STAs may take turns using portions of the TXOP for their UL communication / P2P communication, respectively.

[0215] Fig.15D Illustrated with Fig. 15C A scenario similar to that of , but where the STAs may have a scheduling plan with predefined assignments, so that TXOP access is always given to a specific STA to use the channel first and then share the channel with other STAs. Fig.15DIn the shared TXOP, STA 2 may obtain access to the channel after the backoff timer expires, and send a CTS or a new control frame according to a predefined or assigned scheduling plan, so that STA 1 can access the channel and perform UL transmission or P2P transmission using a portion of the shared TXOP. Therefore, according to some embodiments, after receiving the CTS from STA 2 (e.g., the STA-TXOP winner that initially obtains access to the channel), STA 1 may be considered a TXOP beneficiary and / or TXOP holder of the shared TXOP. In addition, once the TXOP holder (e.g., STA 1) has completed its transmission in the shared TXOP, the remaining STAs in the group (e.g., STA 2 to STA 4) may then sequentially (STA 2, STA 3 and then STA 4) send their UL communications or P2P communications for the remaining duration of the TXOP. However, in the second channel access attempt (after the busy period and backoff timer due to OBSS traffic / other STA traffic expire), a different STA in the group (e.g., STA 3) may be granted access to the channel and send a CTS or a new control frame according to a predefined or assigned scheduling plan to reassign the TXOP holder again (e.g., to STA 1). Therefore, STA 1 can continue to perform UL communication or P2P communication during a portion of the TXOP, and then share the remaining duration of the shared TXOP with other STAs in the group. For example, STA 2, STA 3, and STA 4 may then send their UL signaling / P2P signaling respectively during the corresponding remaining portions of the shared TXOP. In other words, the TXOP winner (e.g., the STA that first obtains access to the channel) may be configured to always share the channel with a specific STA, so that one STA is always the TXOP holder (e.g., the TXOP beneficiary). More specifically, according to some embodiments, the STAs in the group may include a dedicated STA that may act as a dedicated helper to facilitate TXOP sharing.

[0216] Fig.15E Illustrated according to some embodiments FIG. 15C to FIG. 15D A scenario similar to that of , but in which the STAs may be configured such that whichever STA first gains access to the channel (e.g., the TXOP winner) utilizes the TXOP first and then shares the TXOP with other STAs. Fig.15E, STA 1 may gain access to the channel after the backoff timer expires and, as a TXOP holder, utilize a portion of the shared TXOP to perform UL transmission or P2P transmission. Thus, once the TXOP holder (e.g., STA 1) has completed its transmission in the shared TXOP, the remaining STAs in the group (e.g., STA 2 to STA 4) may then sequentially (as an example, STA 2, STA 3 and then STA 4) transmit their UL communications or P2P communications for the remaining duration of the TXOP. However, in a second channel access attempt (after a busy period due to OBSS traffic / other STA traffic and the backoff timer expires), a different STA in the group (e.g., STA 2) may be granted access to the channel first and transmit UL communications or P2P communications as a new TXOP winner and then as a TXOP holder during the first portion of the TXOP. Thus, STA 2 may then share the remaining duration of the shared TXOP with the other STAs in the group. For example, STA 3, STA 4, and STA 1 may then send their UL signaling / P2P signaling respectively during the corresponding remaining parts of the shared TXOP. In other words, according to some embodiments, the TXOP winner (e.g., the STA that first obtains access to the channel) may be configured to always be the TXOP holder. More specifically, according to some embodiments, the STA in the group that wins the TXOP (e.g., the STA that first obtains access to the channel) may act as a dedicated helper to facilitate TXOP sharing. In other words, according to some embodiments, although these STAs may compete for channel access, once the STA accesses the channel, the STA may use the TXOP position allocated to it and share the remaining part with the remaining STAs in the coordinated group according to a predefined ratio.

[0217] also, FIG. 16A to FIG. 16BVarious example scenarios of shared TXOP termination according to some embodiments are illustrated. For example, when a STA shares a TXOP between multiple STAs, there may be a situation in which the STA completes transmission early during part of its TXOP. Therefore, according to some embodiments, the STA that completes its transmission early may deliver the remaining part of the TXOP to the STA scheduled after the STA or alternatively keep transmitting until the end of the STA's allocation period. In other words, according to some embodiments, the promoted STA (e.g., the TXOP beneficiary) may end the TXOP early, or the last STA in the TXOP sharing STA may end the TXOP early. Therefore, in order to enable a STA that may not be a TXOP holder to terminate the TXOP, the send request (RTS) message and CTS message for TXOP reservation should use the group address associated with the group of STAs. Therefore, according to some embodiments, any STA in a group can use the RTS or CTS with the group address to initiate or terminate a shared TXOP.

[0218] For example, Fig.16A It is illustrated that the STA (e.g., STA 2) that first obtains access to the channel may send a CTS message to the group address (e.g., associated with the group ID including STA 1 to STA 4) to the STA to be promoted (e.g., STA 1). Therefore, according to some embodiments, STA 1 can benefit from being promoted and utilize the TXOP by sending UL data to the AP or conducting P2P communication with another STA. In addition, if STA 1 completes its transmission in the TXOP before the end of the TXOP duration, STA 1 may terminate the TXOP early by sending a CTS (or alternatively, a contention-free end (CF-end frame)) to the group address including an indication that the TXOP has been terminated. For example, the CTS may include an indication such as a network allocation vector (NAV) value set to zero (e.g., NAV=0). For example, according to some embodiments, CF-end may indicate the end of the contention-free period and / or NAV=0 may indicate the number of microseconds (e.g., 0 microseconds) that the transmitting STA intends to keep the medium busy.

[0219] Alternatively, Fig. 16BIt is illustrated that the STA (e.g., STA 2) that first obtains access to the channel may send a CTS message to STA 1 to a group address (e.g., associated with a group ID including STA 1 to STA 4) to share the TXOP and make STA 1 the TXOP holder. Therefore, STA 1 may send UL communication / P2P communication and then share the remaining duration of the TXOP with other STAs in the group (e.g., STA 2 to STA 4). Therefore, STA 2, STA 3, and STA 4 may continue their respective UL communication / P2P communication in the TXOP. However, in some cases, the last STA (e.g., STA 4) may complete its UL signaling / P2P signaling before the end of the TXOP duration and then terminate the TXOP early. Therefore, according to some embodiments, STA 4 may terminate the TXOP early by sending a CTS including an indication that the TXOP has been terminated to the group address (e.g., including NAV=0 or alternatively by sending a CF-end frame).

[0220] Additionally, Fig.17 An example of boosting channel access according to some embodiments is illustrated. More specifically, Fig.17 An example according to some embodiments is illustrated, in which the coordination group promotes a STA to access a channel so that the STA can send P2P traffic to one or more STAs in or outside the coordination group in a unicast transmission. For example, according to some embodiments, once one of the STAs in the TXOP sharing group obtains access to the channel, the STA can promote the STA in the group so that one of the STAs is the beneficiary of the TXOP. In other words, the STAs in the coordination group can compete for channel access, and once any of the STAs accesses the channel (e.g., the TXOP winner), the STA can give access to the TXOP to STA 1 (e.g., the TXOP beneficiary). For example, the TXOP winner can transmit a frame to reserve the channel and allow the TXOP beneficiary to use the channel. In some embodiments, the frame can be a CTS message or signal addressed to the TXOP winner, or utilize / include a destination address (DA) to the coordination group address. Therefore, if the group address is used for the CTS destination, the group address can be pre-configured during group formation to specify which STA among the group members should use the channel when a CTS to the group address frame is received. Therefore, according to some embodiments, a STA that becomes a TXOP beneficiary may start sending data after receiving the CTS. In some embodiments, STA 1 may be a mobile AP or a non-AP STA.

[0221] For example, Fig.17A TXOP sharing group including STA 1 to STA 4 (and possibly more STAs) that contend for channel access every "x" seconds (e.g., contend for channel access according to a configured cadence) is illustrated. In addition, STA 3 may first gain access to the channel (e.g., win the TXOP) and send a CTS to STA 1 (or alternatively to the group address). As a result, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send P2P communications to other STAs in the coordination group. For example, during the TXOP sharing duration in which the TXOP is protected, STA 1 may send P2P communications to STA 2 to STA 4 (and additional STAs in the TXOP sharing group) and receive corresponding block acknowledgments (BAs) from the corresponding STAs.

[0222] In addition, after another round of contention, STA 2 may first obtain access to the channel (e.g., win the TXOP) and send a CTS to STA 1 (or alternatively to the group address). Therefore, STA 1 may again become the TXOP beneficiary and may therefore access and utilize the channel to send P2P communications to other STAs in the coordination group (e.g., TXOP sharing group) and receive corresponding BAs from the respective STAs. Similarly, according to some embodiments, after another round of contention for accessing the channel, STA 1 may first obtain access to the channel and then send P2P communications to other STAs in the TXOP sharing group and receive corresponding BAs from the respective STAs.

[0223] 18A to 18D Various additional examples of enhancing channel access according to some embodiments are illustrated. For example, Fig.18A An example scenario is illustrated in which the coordination group promotes STA 1 to access the channel. Therefore, STA 1 can send P2P services (e.g., data) to one or more STAs within or outside the coordination group in a broadcast transmission or a multi-user (MU) transmission. More specifically, Fig.18AA TXOP sharing group is illustrated that includes STA 1 to STA 4 (and possibly additional STAs) that contend for channel access every "x" seconds according to a configured cadence. In addition, STA 3 may first win the TXOP (e.g., gain access to the channel) and send a CTS to STA 1 (or alternatively to a group address). As a result, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send P2P communications to other STAs in the coordination group. For example, during the TXOP sharing duration in which the TXOP is protected, STA 1 may send P2P communications to STA 2 to STA 4 (and additional STAs in the TXOP sharing group). In addition, as part of or in addition to P2P communications, STA 1 may send a multi-user block acknowledgement request (MU-BAR) so that STA 2 to STA 4 simultaneously respond to STA 1 with corresponding BAs.

[0224] In addition, after another round of contention, STA 2 may first gain access to the channel (e.g., win the TXOP) and send a CTS to STA 1 (or alternatively to the group address). As a result, STA 1 may again become the TXOP beneficiary and send P2P communications (with one or more MU-BARs) to other STAs in the coordination group and simultaneously receive corresponding BAs from the respective STAs. Similarly, according to some embodiments, after another round of contention for access to the channel, STA 1 may first gain access to the channel and then send P2P communications (with one or more MU-BARs) to other STAs in the coordination group and simultaneously receive corresponding BAs from the respective STAs.

[0225] Alternatively, Fig.18B An example scenario is illustrated in which a coordination group promotes a STA to access a channel and the STA sends UL traffic to an AP after obtaining access to the channel according to some embodiments. More specifically, Fig.18B A TXOP sharing group including STA 1 to STA 4 (and possibly additional STAs) competing for channel access every "x" seconds according to a configured cadence is illustrated. In addition, STA 3 may first win the TXOP (e.g., gain access to the channel) and send a CTS to STA 1 (or alternatively to the group address). As a result, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send UL communications to the AP. For example, during the TXOP sharing duration in which the TXOP is protected, STA 1 may send UL data to the AP and subsequently receive a BA from the AP.

[0226] In addition, after another round of contention, STA 2 may first gain access to the channel (e.g., win the TXOP) and send a CTS to STA 1 (or alternatively to the group address). As a result, STA 1 may again become the TXOP beneficiary and send UL data to the AP and receive another BA from the AP. Similarly, according to some embodiments, after another round of contention for access to the channel, STA 1 may first gain access to the channel and then send additional UL data to other APs and receive another BA from the AP.

[0227] Fig.18C An example scenario for STA coordinated channel access for a TXOP sharing group of STAs according to some embodiments is illustrated. For example, Fig.18C A TXOP sharing group is illustrated including STA 1 to STA 4 (and possibly more STAs) contending for channel access every "x" seconds (e.g., contending for channel access according to a configured cadence and as indicated by three converging lines on each STA). In addition, STA 3 may first obtain access to the channel (e.g., win the TXOP) and send an RTS to STA 1 where TA is the group address and RA is STA 1. In addition, according to some embodiments, the RTS may include an indication of the RTS NAV duration. For example, according to some embodiments, the RTS NAV duration may correspond to a duration extending from the end of the RTS to the end of the TXOP sharing duration. Therefore, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send a CTS to the group (e.g., RA=group address) and further send P2P communications to other STAs in the coordination group. For example, during the TXOP sharing duration in which the TXOP is protected, STA 1 may send P2P communications to STA 2 to STA 4 (and additional STAs in the TXOP sharing group) and receive corresponding block acknowledgements (BAs) from the corresponding STAs.

[0228] In addition, according to some embodiments, after another round of contention, STA 2 may first obtain access to the channel (e.g., win the TXOP) and send an RTS to STA 1, the RTS including the TA as the group address, the RA as STA 1, and an indication of the RTS NAV duration. Therefore, STA 1 may become the TXOP beneficiary again, and may therefore access and utilize the channel to send another CTS with the group address as the RA and additional P2P communication to other STAs in the TXOP sharing group (during the TXOP sharing duration (e.g., CTS NAV duration) in which the TXOP is protected). Therefore, STA 1 may receive the corresponding BA from the corresponding STA. Similarly, according to some embodiments, after another round of contention for accessing the channel, STA 1 may first obtain access to the channel, and then send an RTS (including TA as the group address and RA (itself) as STA 1) and a CTS with the group address as RA and P2P communication (during the TXOP sharing duration (e.g., CTS NAV duration) during which the TXOP is protected) to other STAs in the TXOP sharing group, and receive corresponding BAs from the corresponding STAs. In other words, Fig.18C A mechanism according to some embodiments is directed to where a TXOP beneficiary determines a TXOP duration (which may be less than or equal to the RTS NAV duration) to reserve a medium (eg, channel) based on its traffic needs.

[0229] Fig.18D An example scenario for STA coordinated channel access for a TXOP sharing group of STAs according to some embodiments is illustrated. For example, Fig.18D A TXOP sharing group including STA 1 to STA 4 (and possibly more STAs) that contend for channel access every "x" seconds (e.g., contend for channel access according to a configured cadence) is illustrated. In addition, STA 3 may first obtain access to the channel (e.g., win the TXOP) and send an RTS to STA 1 where TA is the group address and RA is STA 1. Additionally, according to some embodiments, the RTS may include an indication of NAV=0. Therefore, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send a CTS to the group (e.g., RA=group address) and further send P2P communications to other STAs in the coordination group. For example, during the TXOP sharing duration (e.g., also shown as CTS NAV duration) in which the TXOP is protected, STA 1 may send P2P communications to STA 2 to STA 4 (and other STAs in the TXOP sharing group) and receive corresponding block acknowledgments (BAs) from the corresponding STAs.

[0230] In addition, according to some embodiments, after another round of contention, STA 2 may first gain access to the channel (e.g., win the TXOP) and send an RTS to STA 1, which includes TA as the group address, RA as STA 1, and NAV = 0. Therefore, STA 1 may become the TXOP beneficiary again, and may therefore access and utilize the channel to send another CTS with the group address as the RA and additional P2P communication to other STAs in the TXOP sharing group (during the TXOP sharing duration (e.g., CTS NAV duration) during which the TXOP is protected). Therefore, STA 1 may receive the corresponding BA from the corresponding STA. Similarly, according to some embodiments, after another round of competition for access to the channel, STA 1 may first obtain access to the channel, and then send an RTS (including TA as the group address, RA (itself) as STA 1, and NAV=0) and a CTS with the group address as the RA and P2P communication to other STAs in the TXOP sharing group (during the TXOP sharing duration (e.g., CTSNAV duration) in which the TXOP is protected), and receive a corresponding BA from the corresponding STA.

[0231] in other words, Fig.18D For a mechanism, where a TXOP beneficiary transmits a CTS TXOP based on its traffic needs to reserve the medium (e.g., channel) with an exact TXOP duration. Therefore, according to some embodiments, the RA of the CTS may be a group address, and in the case of no traffic at STA 1, the CTS duration may be set such that NAV=0 or the CTS duration may be set long enough to transmit the CF-end.

[0232] Fig.19 An example scenario according to some embodiments is illustrated, where when one of the STAs in the coordination group accesses a channel, the STA gives access in turn to the appropriate STA. More specifically, Fig.19 A TXOP sharing group including STA 1 to STA 4 (and possibly additional STAs) competing for channel access every "x" seconds according to a configured cadence is illustrated. In addition, STA3 may first win the TXOP (e.g., be the first STA to gain access to the channel) and send a CTS to STA 1 (or alternatively to the group address). As a result, STA 1 may become a TXOP beneficiary and may therefore access and utilize the channel to send P2P communications to other STAs in the coordination group or UL data / traffic to the AP during the protected TXOP sharing duration.

[0233] Additionally, after another round of contention, STA 1 may first gain access to the channel (e.g., win the TXOP) and send a CTS to STA 2 (or alternatively to the group address). Thus, STA 2 may become the new TXOP beneficiary and send P2P communications to other STAs or UL data traffic to the AP. Similarly, after another round of contention for access to the channel, STA 4 may first gain access to the channel and then send a CTS to STA 32 (or alternatively to the group address). Thus, according to some embodiments, STA 3 may become the TXOP beneficiary and continue to send P2P communications to other STAs in the coordination group or UL data traffic to the AP.

[0234] In other words, Fig.19 An example implementation of STA coordinated channel access is described, in which the STA can be configured to make a specific STA a TXOP beneficiary. In addition, according to some embodiments, a specific STA can be made a TXOP beneficiary in a specific order. In other words, when one of the STAs in the coordination group accesses the channel, the STA will give access to the STA whose turn it is to become the TXOP beneficiary. According to some embodiments, the order of accessing the channel can be determined or indicated to the STA (e.g., the STA in the coordination group) during the configuration phase. Therefore, the TXOP winner can transmit a frame (e.g., CTS) to reserve the channel and allow the TXOP beneficiaries to use the channel in turn. In some embodiments, the CTS frame can be addressed to the TXOP winner or have a destination address to the coordination group address. Additionally or alternatively, if the group address is used for the CTS destination, the group address can be pre-configured during group formation to indicate which STA among the group members will use the channel (when a CTS to the group address frame is received). Therefore, no matter which STA is indicated as the TXOP beneficiary, the STA can start sending data after receiving the CTS.

[0235] In some embodiments, if a STA is not served by a TXOP due to channel blocking or congestion, the STA may lose its turn and the original order for sharing may continue. Therefore, according to some embodiments, STAs may compete separately outside the regular scheduling plan. In other words, according to some embodiments, if a STA is indicated as the next TXOP beneficiary but cannot utilize the TXOP due to channel blocking or congestion (and various other reasons), then this particular STA may be skipped and the TXOP winner STA may send a CTS to the next indicated TXOP beneficiary in the configured order.

[0236] Fig. 20 An example scenario utilizing coordinated TXOP sharing with an AP according to some embodiments is illustrated. More specifically, Fig.19A scenario according to some embodiments is illustrated, where when one of the STAs in the coordinating group accesses the channel, the TXOP winner STA transmits an RTS to the AP to facilitate data transmission from the STAs in the TXOP sharing group in a preconfigured (or agreed upon) portion of the TXOP.

[0237] For example, Fig. 20 It is illustrated that STAs in the coordination group compete for channel access and STA 1 obtains channel access with the AP. Therefore, once STA 1 has obtained channel access, the STA can transmit an RTS with a group address ID to the AP. In addition, the AP can transmit a CTS as a response to the RTS so that STA 1 can continue to send UL data or services to the AP during its pre-configured time duration or time portion (e.g., TXOP sharing duration). Therefore, the group address of the RTS / CTS can allow the STAs in the TXOP sharing group to identify or determine that the TXOP is shared between the STAs in the TXOP sharing group. In other words, if an RTS and / or CTS with a destination address (equal to the group address of the TXOP sharing group) is transmitted (e.g., RTS and CTS are transmitted through the group address), the STAs in the group can be expected to share the TXOP, and the STAs in the group can identify or determine the TXOP to be shared. In addition, according to some embodiments, an access order can be predefined. According to some embodiments, the STAs in the TXOP sharing group can be expected to be awakened during the expected TXOP sharing time. However, the STA may be allowed to go to sleep after completing utilizing its share.

[0238] Thus, once STA 1 has received the CTS from the AP, STA 1 may use the portion of the TXOP agreed upon in the coordination setup, and may further stop transmitting (after completing its UL transmission to the AP) to allow other STAs in the TXOP sharing group to use the remaining portion of the TXOP (e.g., other pre-configured portions of the TXOP / TXOP sharing duration). In some embodiments, the TXOP shared portion may be fully used by all STAs, such that each STA in the TXOP sharing group uses the pre-agreed portion of the TXOP and completes transmitting its data before the next scheduled shared portion. According to some embodiments, although Fig. 20 Portions of the TXOP including UL data traffic to an AP are illustrated, but the portion of the TXOP assigned to each STA may alternatively be used for P2P data, DL data (if the STA is an AP or a mobile AP), UL data transmission to an AP / mobile AP, or AP transmission to an AP / mobile AP.

[0239] FIG. 21A to FIG. 21B Various examples of early termination of the shared portion by explicit signaling or via channel monitoring according to some embodiments are illustrated. For example, Fig.21A An example scenario of prematurely terminating a shared portion by using explicit signaling according to some embodiments is illustrated. More specifically, Fig.21A A case is illustrated in which a STA may send an invitation transmission (ITS) to the next member or to the group address if the STA completes transmission in advance before the end of its assigned period or has no data to send. In some embodiments, the ITS may be a simple CTS frame with a destination equal to the next STA whose turn it is (e.g., the next STA according to the order or scheduling plan indicated in the configuration information). In other words, according to some embodiments, the next shared STA may start sending its data when triggered by other group member STAs or when it is time for it to be scheduled to transmit. Additionally or alternatively, if a STA receives an early ITS frame, the STA may extend its data transmission time until the boundary of the STA's originally allocated resources. In addition, according to some embodiments, if there is no additional data to be shared, the last STA in the TXOP sharing group may terminate the TXOP early. Additionally, according to some embodiments, a portion of the TXOP assigned to each STA may be used for P2P data, DL data (if the STA is an AP or mobile AP), or UL data transmission to the AP / mobile AP.

[0240] For example, Fig.21A It is illustrated that STA 1 sends an RTS to the AP after obtaining access to the channel and then receives a CTS from the AP. Therefore, STA 1 may continue to send UL data to the AP and then broadcast an ITS to the TXOP sharing group. Therefore, after having received the ITS from STA 1, STA 2 may then continue to send its uplink data in the remaining TXOP sharing duration (e.g., the first TXOP sharing duration) of STA 1's portion of the TXOP. In addition, at the end of the first TXOP sharing duration, STA 3 may continue to send its UL data to the AP and, if the STA completes its transmission in advance, continue to send ITS to the TXOP sharing group. Therefore, according to some embodiments, after having received the ITS from STA 3, STA 4 may continue to send during another TXOP sharing duration, or if STA 4 has no data to send, the STA may send a message including a CF-end parameter to the TXOP sharing group so that the shared portion is terminated in advance.

[0241] Alternatively, Fig. 21BAn example scenario of early termination of a shared portion through channel monitoring according to some embodiments is illustrated. For example, a STA may monitor the transmitted packets in order to decide or determine whether it is the STA's turn to transmit before its scheduled time. In some cases, the UL packet may be followed by a DL acknowledgment (ACK) message such as a BA. Therefore, if a STA in a TXOP sharing group is to monitor and potentially receive a BA from an AP, the STA may determine that the data sent by another STA is successfully delivered to the AP. Alternatively, according to some embodiments, it is possible for a STA in a TXOP sharing group to decode the medium access control (MAC) header of a physical protocol data unit (PPDU) of a previously shared STA to determine that the data sent by another STA is successfully delivered to the AP. Additionally, according to some embodiments, a portion of the TXOP assigned to each STA may be used for P2P data, DL data (if the STA is an AP / mobile AP), or UL data transmission to the AP / mobile AP.

[0242] For example, Fig. 21B The example illustrates that STA 1 sends an RTS to the AP after obtaining access to the channel and subsequently receives a CTS from the AP. Therefore, STA 1 may continue to send UL data to the AP and may transmit a BA from the AP to the TXOP sharing group. Therefore, after having received the BA from the AP, STA 2 may then continue to send its UL data in the allowed TXOP sharing portion of the TXOP, which may include a portion of the first TXOP sharing portion and a portion of the second TXOP sharing portion. In addition, once STA 2 has completed its UL data transmission to the AP, the AP may again send a BA to the TXOP sharing group. Therefore, STA 3 may continue to send its UL data to the AP. Again, in response to the UL transmission from STA 3, the AP may send a BA to the TXOP sharing group. Therefore, according to some embodiments, after having received the BA from the AP, STA 4 may continue to send UL data to the AP during the allowed TXOP sharing portion, or as Fig. 21B As shown, if STA 4 has no data to send, the STA may send a message including a CF-end parameter to the TXOP sharing group so that the shared part is terminated early.

[0243] Fig. 22Another variation of TXOP sharing between STAs in a TXOP sharing group according to some embodiments is illustrated. In some cases, the order of access to the channel may determine how many resources each STA may have. For example, if any STA in the STA does not use some or all of its resources within its protected TXOP sharing duration, then at the end of the TXOP, these STAs may obtain (or access) more or additional resources of the TXOP. In addition, according to some embodiments, it is possible for the STA to go to sleep earlier at the beginning of the TXOP, and therefore it may not be necessary to monitor the channel during the entire TXOP until these STAs receive their resource assignments. Therefore, in order to create a balanced transmission schedule (which does not cause STAs to gain access to the channel more frequently than the order), the order of access to the channel may be adjusted so that the resource gain and power loss tradeoffs are taken into account.

[0244] For example, if there is a need for STAs to prefer TXOP resources rather than power consumption, it may be possible to adjust the channel access order by assigning these STAs to the end of the TXOP shared schedule. In other words, since some STAs may need or prioritize available resources, these STAs may benefit from the possibility of additional resources being available near the end of the TXOP due to the previous STA completing transmission early. Alternatively, if there is a need for STAs to prefer or prioritize power savings rather than additional TXOP resources, it may be beneficial to adjust the channel access order (e.g., sequence) so that these STAs are assigned to the beginning of the TXOP. In other words, since these STAs may need additional power savings, it may be beneficial for these STAs to access the channel early (or first) in the TXOP so that they can go to sleep (e.g., save power) after transmission.

[0245] For example, Fig. 22 TXOP sharing groups are illustrated that contend for channel access every "x" seconds according to a configured cadence. In addition, Fig. 22 The scenario in which STA 3 first obtains access to the channel and then sends a CTS to STA 1 (or the group address) is illustrated. Therefore, it is possible that STA 3 makes STA 1 (according to the adjusted channel access order or sequence) the TXOP beneficiary due to its need or priority for power saving rather than TXOP resources. Similarly, Fig. 22It is illustrated that STA 4 according to some embodiments may be placed at the end of the adjusted channel access order or sequence because it prioritizes TXOP resources rather than power saving. For example, according to some embodiments, if any of STA 1 to STA 3 is able to terminate its transmission early, STA 4 may benefit from the additional resources of the protected TXOP shared duration by being at the end of the channel access order or sequence. As another alternative, according to some embodiments, the STA may be configured so that the assignment of resources is static. In other words, each STA accessing the medium may be allocated the same amount of resources so that the protected TXOP shared duration portion of each STA is the same. In addition, according to some embodiments, the assigned resources may be used for P2P services, UL services, or DL ​​services. In other words, according to some embodiments, the data block may be a P2P service, a UL service, or a DL service.

[0246] Fig.23 Additional variations of TXOP sharing among STAs in a TXOP sharing group according to some embodiments are illustrated. In some cases, it may be beneficial to balance power and resource distribution among STAs in a TXOP sharing group. Therefore, the scheduled channel access order may be adjusted so that the scheduled channel access order rotates based on the access time. For example, Fig.23 An example scenario is illustrated in which the first channel access order is implemented by the TXOP winner (e.g., STA 3) so that the channel access order is first given to STA 1 as the TXOP beneficiary and then to STA 2, STA 3, and finally to STA 4. However, after the next round of access contention, STA 4 may obtain the first access to the channel and accordingly proceed to make STA 2 the TXOP beneficiary so that the STA can send data first. Therefore, STA 3, STA 4, and STA 1 will then be able to transmit during the TXOP sharing duration, respectively. In other words, according to some embodiments, the channel access order or sequence may be adjusted so that the beneficiaries of the TXOP are evenly distributed so as to provide each STA in the TXOP sharing group with an opportunity to become a TXOP beneficiary (e.g., to transmit first in the TXOP sharing duration). Additionally or alternatively, if the channel is blocked or congested for one access period, this order or sequence may be passed or skipped to avoid synchronization problems. In addition, according to some embodiments, the assigned resources may be used for P2P services, UL services, or DL ​​services. In other words, according to some embodiments, the data block may be P2P traffic, UL traffic or DL ​​traffic.

[0247] Fig.24 Additional example scenarios of TXOP sharing among STAs in a TXOP sharing group according to some embodiments are illustrated. More specifically, Fig.24The example illustrates a scenario where TXOP sharing is coordinated by the TXOP winner (eg, first to access the channel). Fig.24 A TXOP sharing group including STA 1 that first obtains access to the channel is illustrated. Therefore, STA 1 (as the TXOP holder) may send an RTS to the AP and subsequently receive a CTS from the AP. STA 1 may then continue to send UL data to the AP and then send an ITS to the next user in the scheduling plan (e.g., the next STA in order or sequence) after all of its data has been sent before the end of the TXOP sharing duration. In other words, the TXOP holder (e.g., STA 1 in this example) may transmit an ITS frame to the next STA in the TXOP sharing group according to the channel access order or sequence. Therefore, after STA 2 has sent its UL data to the AP, STA 1 may transmit another ITS to the next STA in the TXOP sharing group (e.g., STA 3). Therefore, STA 3, which may not have any data to send, may send an ITS to the TXOP holder (e.g., STA 1) to indicate the lack of data to send. Therefore, STA 1 may send another ITS to STA 4 (as the next STA in the channel access order), and STA 4 may send its UL data to the AP accordingly. In addition, according to some embodiments, if STA 4 finishes sending its UL data before the TXOP sharing duration has elapsed, the STA may additionally transmit an ITS to the TXOP holder STA 1. In other words, Fig.24 A mechanism is illustrated in which the TXOP holder transmits an ITS to the next user (e.g., STA) in the scheduling plan. Thus, the STA group member sends its data when it is time to transmit or when it is triggered in advance by the TXOP holder. In addition, the ITS frame can alternatively be a CTS frame for the coordinator (e.g., STA 1) or a newly defined frame.

[0248] Figure 25 to Figure 2 8—Example Aspects of AP Coordination of Channel Access

[0249] Figure 25 to Figure 2 8 illustrates example aspects of AP coordinated channel access for a TXOP sharing group according to some embodiments. Additionally, according to some embodiments, Fig.14 The method can also correspond to Figure 25 to Figure 2 The examples shown in 8.

[0250] For example, Fig.25 A scenario is illustrated in which a TXOP sharing group has been formed and resource allocation has been set for the TXOP group (e.g., according to a configuration). Thus, according to some embodiments, STAs in the TXOP sharing group (e.g., STA 1 to STA3 and additional STAs) may be associated with a group ID. More specifically, Fig.25It is illustrated that STA 1 first obtains access to the channel as a TXOP winner and then transmits an initial control frame (ICF) from the group address to the AP. Therefore, the AP may determine that the TXOP is a shared TXOP based at least in part on receiving a frame with a group address. Therefore, according to some embodiments, the AP may respond to STA 1 with a CTS and control the TXOP. In addition, according to some embodiments, the AP may continue to transmit triggered TXOP sharing (TXS) frames to the STAs in the TXOP sharing group in a preconfigured order or sequence. In addition, according to some embodiments, if one of the STAs completes transmission before the assigned time (e.g., the TXOP sharing duration), the AP may utilize a point coordination function (PCF) interframe space (PIFS) recovery procedure to acquire or control the medium (e.g., channel). In addition, according to some embodiments, the data sent by the STA during the shared TXOP may be UL data services or P2P services.

[0251] FIG. 26A to FIG. 26B Various example scenarios for AP coordinated channel access for a TXOP sharing group according to some embodiments are illustrated. More specifically, Fig.26A The mechanism for the AP to receive feedback from STAs in the TXOP sharing group if they have traffic to transmit is illustrated. For example, Fig.26AIt is illustrated that STA 1 first obtains access to the channel as a TXOP winner and then transmits an ICF to the AP using a transmitter address (TA) as a group address. Therefore, the AP may determine that the TXOP is a shared TXOP based at least in part on receiving a frame with a group address. Therefore, according to some embodiments, the AP may respond to STA 1 with a CTS using a receiver address (RA) as the group address of the TXOP sharing group, and then control the TXOP. Additionally, according to some embodiments, as part of or in addition to the CTS, the AP may send a null data packet (NDP) feedback report poll (NFRP) to the STAs (e.g., STA 1 to STA 3, etc.) of the TXOP sharing group. Therefore, STA 1 to STA 3 (and any other STAs in the TXOP sharing group) may continue to send NDP feedback (FB) to the AP. According to some embodiments, after having received the NDP FB, the AP may then send TXS frames to the STAs, which indicate via the NDP FB that they have data to send. Therefore, in response to receiving TXS frames from the AP respectively, these STAs may respectively send data (e.g., P2P data traffic or UL data traffic). In other words, it is possible for the AP to get feedback from the shared group STAs to determine whether they have traffic to transmit. The AP may achieve this by transmitting an NFRP trigger frame (TF) to the shared group STAs and receiving an NDP feedback report to indicate whether they have traffic. If the STA responds affirmatively (e.g., indicating that they do have data to send), the AP may schedule TXS for these STAs. Alternatively, according to some embodiments, if the AP receives feedback that one of the STAs has no traffic, the AP may terminate the TXOP early for the STA.

[0252] In addition, after another round of contention for channel access, STA 3 may be the first STA to gain access to the channel as a TXOP winner, and thus STA 3 may subsequently transmit an ICF to the AP using TA as the group address. Thus, the AP may determine that the TXOP is a shared TXOP based at least in part on receiving a frame with the group address. Thus, according to some embodiments, the AP may respond to STA 3 with a CTS using an RA as the group address of the TXOP sharing group, and then control the TXOP. Additionally, according to some embodiments, as part of or in addition to the CTS, the AP may send an NFRP to the STAs of the TXOP sharing group (e.g., STA 1 to STA 3, etc.). Thus, STA 1 to STA 3 (and any additional STAs in the TXOP sharing group) may continue to send NDP FBs to the AP.

[0253] According to some embodiments, after having received the NDP FB, the AP may then send a TXS frame to the STAs (e.g., STA 1 and STA 3) in the TXOP sharing group, which indicate via the NDP FB that they have data to transmit. Therefore, in response to receiving the TXS frame from the AP, respectively, these STAs may respectively send data (e.g., P2P data traffic or UL data traffic). In addition, according to some embodiments, after having determined that STA 2 has no data to send (e.g., as indicated in the NDP FB), the AP may send a CTS including a CF-end value to terminate the TXOP sharing duration early.

[0254] Fig.26B Additional example scenarios for AP coordinated channel access for a TXOP sharing group of STAs according to some embodiments are illustrated. For example, it is possible for the AP to obtain more information about the duration required to transmit a TXS to the STAs in the TXOP sharing group. More specifically, Fig.26B It is illustrated that STA 1 first obtains access to the channel as a TXOP winner and then transmits an ICF to the AP using a transmitter address (TA) as a group address. Therefore, the AP may determine that the TXOP is a shared TXOP based at least in part on receiving a frame with a group address. Therefore, according to some embodiments, the AP may respond to STA 1 with a CTS using a receiver address (RA) as the group address of the TXOP sharing group, and then control the TXOP. Additionally, according to some embodiments, as part of or in addition to the CTS, the AP may send an RTS message to STA 1 of the TXOP sharing group (e.g., STA 1 to STA 4, etc.). In some embodiments, the duration of the RTS may be the maximum allowed shared duration of the STAs of the TXOP sharing group. Therefore, according to some embodiments, STA 1 may continue to send CTS to the AP, wherein the duration of the CTS may represent the requested duration (wherein the CTS duration is less than or equal to the RTS duration).

[0255] According to some embodiments, after having received a CTS with a requested duration, the AP may then send a TXS frame to the STAs, which indicate the requested duration for TXOP transmission via the corresponding CTS frame. Therefore, in response to receiving TXS frames from the AP respectively, these STAs may respectively transmit data (e.g., P2P data traffic or UL data traffic). In other words, if the STA responds affirmatively (e.g., indicating a specified duration for transmitting data), the AP may schedule TXS for these STAs and these STAs may continue their transmission. Alternatively, according to some embodiments, if the AP receives feedback that one of these STAs has no traffic (e.g., if the requested duration in the CTS is zero), the AP may terminate the TXOP early for the STA. In other words, by transmitting an RTS before each STA data transmission in order to determine the requested duration of each STA's transmission, this may allow the AP to coordinate the TXOP sharing group and its data transmission more flexibly and efficiently.

[0256] Fig. 27 Another example scenario of AP coordinated channel access for a TXOP sharing group of STAs according to some embodiments is illustrated. More specifically, Fig. 27 It is illustrated that STA 1 is the first STA to access the channel in the TXOP sharing group and then transmits an ICF to the AP using TA as the group address. Therefore, the AP can determine that the TXOP is a shared TXOP based at least in part on receiving a frame with the group address. Therefore, according to some embodiments, the AP can respond to STA 1 with a CTS using RA as the group address of the TXOP sharing group and then control the TXOP.

[0257] According to some embodiments, STA 1 may then continue to transmit its UL data to the AP without further waiting for AP scheduling. Additionally, once the STA has completed its intended UL data transmission, the STA may transmit a CTS frame (or ICF frame) to the AP to indicate that it is willing to share the remainder of the TXOP with the AP. In some embodiments, according to some embodiments, the group address may be used as the TA to transmit the CTS or ICF, and the receiving party (e.g., the AP) may use the group address as the RA. Again, when a frame with a group address is received, this may indicate that the TXOP is a shared TXOP, and the AP may control the TXOP again. The AP may then continue to transmit TXS frames to the STAs in the TXOP sharing group as pre-configured. Additionally, according to some embodiments, if one of the STAs completes before the assigned time, it is possible for the AP to utilize PIFS recovery to control the channel.

[0258] As previously discussed, TXOP sharing group formation and resource allocation may be established before any of the STAs attempts to gain access to the channel. For example, according to some embodiments, the STAs in the TXOP sharing group form a group with a group ID. Additionally, according to some embodiments, the data transmitted during the shared resource period may be UL data or P2P traffic.

[0259] Additionally, according to some embodiments, the data frames in any of the previous figures may be represented as one or more PPDUs and their BA responses. In addition, at least in some cases, the data or frames (e.g., RTS, CTS, P2P, BA, etc.) sent and received in any of the previous figures may generally not overlap in time. For example, according to some embodiments, although not explicitly shown in at least some of the figures, there may be at least one short interframe space (SIF) between the frames. In addition, according to some embodiments, although not explicitly shown in at least some of the figures, the backoff counter may start or continue after the start of the contention period. For example, according to some embodiments, before the backoff counter is started, this may correspond to the start of the contention period for obtaining access to the channel.

[0260] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

[0261] In some embodiments, a first non-access point (non-AP) station in a group of at least two non-AP stations may receive signaling including information corresponding to a transmit opportunity (TXOP) from a second non-AP station in the group of at least two non-AP stations. Additionally, the first non-AP station may send first data to one or more devices based on the information corresponding to the TXOP and scheduling information associated with the group of at least two non-AP stations, wherein the first data is sent to the one or more devices in at least a portion of the TXOP.

[0262] According to some embodiments, the signaling including information corresponding to the TXOP may indicate that only the first non-AP station is to use at least a portion of the TXOP to send the first data. In addition, according to some embodiments, when the first non-AP station completes sending the first data before the end of the TXOP, the method may further include: sending a control frame to a group address associated with the group of at least two non-AP stations to terminate the TXOP, the control frame message including one or more parameters.

[0263] According to further embodiments, the method may further include: sending one or more multi-user block acknowledgement requests (MU-BARs) to the at least two non-AP sites, and receiving one or more block acknowledgements (BAs) from the at least two non-AP sites. Additionally or alternatively, the signaling including information corresponding to the TXOP may instruct the first non-AP site and one or more other non-AP sites in the group of at least two non-AP sites to use at least a portion of the TXOP to send data to the one or more devices, respectively. In addition, according to some embodiments, when one of the at least two non-AP sites completes corresponding data transmission before the end of the TXOP, the method may further include: receiving a control frame to terminate the TXOP based on a group address associated with the group of at least two non-AP sites, the control frame including one or more parameters.

[0264] In some embodiments, the group of at least two non-AP sites may be associated with a group address or a group identifier (ID). Additionally or alternatively, the first data may be sent to one or more devices, the one or more devices including at least one of the following: one or more APs, one or more mobile APs, one or more non-APs, or one or more non-AP sites (STAs). According to some embodiments, the signaling including information corresponding to a transmit opportunity (TXOP) may further include a control frame including addresses of the group of at least two non-AP sites. In some embodiments, the method may be performed after one or more contention periods have passed.

[0265] According to some embodiments, a processor may include a memory storing instructions that, when executed, cause a first non-access point (non-AP) station to: establish a wireless link with an access point (AP) via an access channel. Additionally, the instructions are further executable to cause the first non-AP station to: send a request corresponding to a transmit opportunity (TXOP) and including an address of the first non-AP station to the AP. Furthermore, the instructions are further executable to cause the first non-AP station to: receive a response from the AP, and send first data in at least a portion of the TXOP according to scheduling information associated with the first non-AP station.

[0266] In some embodiments, when the first non-AP station completes sending the first data before the end of the TXOP, the instructions are further executable to cause the first non-AP station to: broadcast one or more control frames to a group address of at least two non-AP stations to invite the at least two non-AP stations to send. In addition, the request may include an instruction to cause only one of the at least two non-AP stations to send data using at least a portion of the TXOP. Additionally or alternatively, the instructions are further executable to cause the first non-AP station to: receive one or more invitation to send (ITS) messages from one or more non-AP stations of the at least two non-AP stations. In some embodiments, the one or more ITS messages may indicate to the first non-AP station that the non-AP station has no data to send or that the non-AP station has completed data transmission before a portion of the TXOP ends.

[0267] According to a further embodiment, an access point (AP) may include a radio component and a processor that is operably coupled to the radio component. In addition, the processor may be configured to cause the AP to: establish a wireless link with a first non-AP site in a group of at least two non-access points (non-APs) via an access channel. Additionally, the processor may be configured to cause the AP to: receive signaling from the first non-AP site, the signaling including at least one of an address of the group of at least two non-APs or a single non-AP site and a transmit opportunity (TXOP) sharing request indication. In addition, the processor may be configured to cause the AP to: send a response including a TXOP sharing indication to the first non-AP site, and send additional responses including TXOP sharing indications to additional non-AP sites in the group of at least two non-AP sites.

[0268] In some embodiments, the processor may be further configured to cause the AP to: send one or more null data packet feedback report polls (NFRPs) to one or more non-AP stations in the group of at least two non-AP stations. Additionally, the processor may be further configured to cause the AP to: send one or more request to transmit (RTS) messages to one or more non-AP stations in the group of at least two non-AP stations. Additionally or alternatively, according to some embodiments, the duration of the RTS message may be the maximum allowed shared duration. In some embodiments, the processor may be further configured to cause the AP to: receive one or more control frames from one or more non-AP stations in the group of at least two non-AP stations. Additionally, according to some embodiments, the duration of the control frame may indicate that the requested duration is less than or equal to the maximum allowed shared duration. In addition, the processor may be further configured to cause the AP to: perform point coordination function inter-frame space (PIFS) recovery of the access channel in response to one or more non-AP stations in the group of at least two non-AP stations completing transmission before the assigned time.

[0269] The embodiments of the present disclosure may be implemented in any of a variety of forms. For example, some embodiments may be implemented as computer-implemented methods, computer-readable storage media, or computer systems. Other embodiments may be implemented using one or more custom-designed hardware devices such as ASICs. Other embodiments may be implemented using one or more programmable hardware elements such as FPGAs.

[0270] In some embodiments, a non-transitory computer-readable storage medium may be configured such that it stores program instructions and / or data, wherein if executed by a computer system, the program instructions cause the computer system to perform a method, such as any one of the method embodiments described herein, or any combination of the method embodiments described herein, or any subset of any of the method embodiments described herein or any combination of such subsets.

[0271] In some embodiments, the wireless device may be configured to include a processor (and / or a set of processors) and a memory medium, wherein the memory medium stores program instructions, wherein the processor is configured to read and execute the program instructions from the memory medium, wherein the program instructions are executable to cause the wireless device to implement any of the various method implementations described herein (or any combination of the method implementations described herein, any combination of these subsets). The device may be implemented in any of various forms.

[0272] Although the above embodiments have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to include all such variations and modifications.

Claims

1. A method, comprising: At a first non-access point (non-AP) station in a group of at least two non-AP stations: receiving signaling including information corresponding to a transmit opportunity (TXOP) from a second non-AP station in the set of at least two non-AP stations; as well as First data is transmitted to one or more devices based on the information corresponding to the TXOP and scheduling information associated with the set of at least two non-AP stations, wherein the first data is transmitted to the one or more devices in at least a portion of the TXOP.

2. The method according to claim 1, wherein the signaling instruction including the information corresponding to the TXOP causes only the first non-AP station to send the first data using at least a portion of the TXOP.

3. The method according to claim 2, wherein: When the first non-AP station completes sending the first data before the TXOP ends, the method further includes: A control frame is sent to a group address associated with the group of at least two non-AP stations to terminate the TXOP, the control frame including one or more parameters.

4. The method according to claim 2, wherein the method further comprises: sending one or more multi-user block acknowledgement requests (MU-BARs) to the at least two non-AP stations; as well as One or more block acknowledgements (BAs) are received from the at least two non-AP stations.

5. The method of claim 1 , wherein the signaling instruction including information corresponding to the TXOP causes the first non-AP station and one or more additional non-AP stations in the group of at least two non-AP stations to respectively send data to the one or more devices using at least a portion of the TXOP.

6. The method according to claim 5, wherein: When one of the at least two non-AP stations completes corresponding data transmission before the TXOP ends, the method further includes: A control frame is received to terminate the TXOP based on a group address associated with the group of at least two non-AP stations, the control comprising one or more parameters.

7. The method of claim 1, wherein the group of at least two non-AP stations is associated with a group address or a group identifier (ID).

8. The method of claim 1, wherein the first data is sent to one or more devices, the one or more devices comprising at least one of the following: One or more APs; One or more mobile APs; One or more non-APs; or One or more non-AP stations (STAs).

9. The method of claim 1, wherein the signaling including information corresponding to a transmit opportunity (TXOP) includes a control frame, the control frame including addresses of the group of at least two non-AP stations.

10. The method of claim 1, wherein the method is performed after one or more contention periods have elapsed.

11. A processor, comprising: a memory storing instructions that, when executed, cause a first non-access point (non-AP) station to: Establishing a wireless link with an access point (AP) via an access channel; sending a request corresponding to a transmit opportunity (TXOP) and including an address of the first non-AP station to the AP; receiving a response from the AP; as well as First data is sent in at least a portion of the TXOP according to scheduling information associated with the first non-AP station.

12. The processor of claim 11, wherein: When the first non-AP station completes sending the first data before the TXOP ends, the instructions are further executable to enable the first non-AP station to: One or more control frames are broadcast to a group address of at least two non-AP stations to invite the at least two non-AP stations to transmit.

13. The processor of claim 11, wherein the request comprises an indication for only one of the at least two non-AP stations to transmit data using at least a portion of the TXOP.

14. The processor of claim 11, wherein the instructions are further executable to cause the first non-AP station to: One or more Invite to Send (ITS) messages are received from one or more non-AP stations of the at least two non-AP stations.

15. The processor of claim 14, wherein the one or more ITS messages indicate to the first non-AP station that the non-AP station has no data to transmit or that the non-AP station has completed data transmission before a portion of the TXOP ends.

16. An access point (AP), the AP comprising: Radio components; and a processor operably coupled to the radio and configured to cause the AP to: establishing a wireless link with a first non-AP station in a group of at least two non-access points (non-APs) via an access channel; receiving signaling from the first non-AP station, the signaling comprising at least one of addresses of the group of at least two non-APs or an address of a single non-AP station and a transmit opportunity (TXOP) sharing request indication; sending a response including a TXOP sharing indication to the first non-AP station; as well as Additional responses each including a TXOP sharing indication are sent to additional non-AP stations in the set of at least two non-AP stations.

17. The AP of claim 16, wherein the processor is further configured to cause the AP to: One or more Null Data Packet Feedback Report Polls (NFRPs) are sent to one or more non-AP stations in the set of at least two non-AP stations.

18. The AP of claim 16, wherein the processor is further configured to cause the AP to: One or more request to send (RTS) messages are sent to one or more non-AP stations in the set of at least two non-AP stations, wherein the duration of the RTS messages is a maximum shared duration allowed.

19. The AP of claim 18, wherein the processor is further configured to cause the AP to: One or more control frames are received from one or more non-AP stations in the set of at least two non-AP stations, wherein a duration of the control frames indicates that a requested duration is less than or equal to the allowed maximum sharing duration.

20. The AP of claim 19, wherein the processor is further configured to cause the AP to: In response to one or more non-AP stations in the group of at least two non-AP stations completing transmission before an assigned time, performing a point coordination function inter-frame space (PIFS) recovery of the access channel.

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