Medium protection during dynamic power-saving operation

Abstract

The embodiment includes an access point (AP) that can perform state transitions while operating under dynamic power saving conditions, thereby determining that the AP can transition between reduced and enhanced operating parameter states without causing loss of media synchronization at the AP and preventing frame loss, including by transmitting frames to itself to set a duration sufficient for performing the state transition or by requesting assistance from a station (STA) to perform the state transition, or by identifying ongoing transmissions not addressed to the AP (during which the transition can be performed).

Description

Technical Field

[0001] This disclosure generally relates to wireless communication systems, and more specifically, to media protection during dynamic power saving (DPS) operation at access points (APs) in wireless networks, for example, but not limited to. Background Technology

[0002] Since the late 1990s, Wireless Local Area Network (WLAN) technology has evolved towards increasing data rates and continues to grow in various markets such as homes, businesses, and hotspots. WLAN allows devices to access the Internet in the 2.4 GHz, 5 GHz, 6 GHz, or 60 GHz frequency bands. WLAN is based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. The IEEE 802.11 standard family aims to improve speed and reliability and extend the operational range of wireless networks.

[0003] WLAN devices increasingly need to support a variety of latency-sensitive or real-time applications, such as augmented reality (AR), robotics, artificial intelligence (AI), cloud computing, and autonomous vehicles. To achieve the extremely low latency and extremely high throughput required for such applications, Multi-Link Operation (MLO) has been proposed for WLANs. A WLAN is formed by WLAN devices within a limited area such as a home, school, apartment, or office building. Each WLAN device can have one or more stations (STAs), such as access point (AP) STAs and non-access point (non-AP) STAs.

[0004] MLO enables non-AP multi-link devices (MLDs) to establish multiple links with AP MLDs. Each of these links can independently enable channel access and frame switching between the non-AP MLD and the AP MLD, which can reduce latency and increase throughput.

[0005] The descriptions set forth in the Background section should not be assumed to be prior art simply because they are set forth in the Background section. The Background section may describe aspects or embodiments of this disclosure. Summary of the Invention

[0006] Solution to the problem

[0007] One aspect of this disclosure provides an access point (AP) in a wireless network, including: a memory; and a processor coupled to the memory. The processor is configured to operate in a first state of a dynamic power-saving mode. The processor is configured to determine a capability to transition to a second state of the dynamic power-saving mode. The processor is configured to transition to the second state of the dynamic power-saving mode based on the determined capability during a Network Assignment Vector (NAV) duration.

[0008] In some embodiments, the first state is a reduced operating parameter state, and the second state is an enhanced operating parameter state; the first state is the enhanced operating parameter state, and the second state is the reduced parameter state; or the first state is a reduced operating parameter state without transmission capability, and the second state is a reduced operating parameter state with transmission capability.

[0009] In some embodiments, the processor is further configured to detect the preamble of a frame that is not addressed to the AP, and the NAV duration is associated with the frame.

[0010] In some embodiments, the processor is further configured to send frames to set the NAV for at least the time period required to transition to the second state.

[0011] In some embodiments, the processor is further configured to: send a first frame to a station (STA) indicating that the AP intends to transition from a first state to a second state; and receive from the STA a second frame in response to the first frame, the second frame including padding, wherein the AP transitions to the second state at or before the end of the padding.

[0012] In some embodiments, the processor is further configured to receive a frame including padding from a slave station (STA), wherein the AP transitions to a second state at or before the end of the padding.

[0013] In some embodiments, frames are transmitted over the full bandwidth of the transmission opportunity (TXOP) or over the primary 20 MHz bandwidth of the TXOP.

[0014] In some embodiments, the processor is further configured to send an acknowledgment frame to the STA in response to the frame.

[0015] In some embodiments, the processor is further configured to apply one or more transmission parameters associated with the current state to which the AP belongs.

[0016] One aspect of this disclosure provides a station (STA) in a wireless network, including: a memory; and a processor coupled to the memory. The processor is configured to: receive a first frame from an access point (AP), the first frame indicating that the AP intends to transition from a first state of dynamic power-saving mode to a second state. The processor is configured to send a second frame to the AP in response to the first frame, the second frame including padding, wherein the AP transitions to the second state at or before the end of the padding.

[0017] In some embodiments, the processor is further configured to send a third frame to the AP to indicate one or more of the following: the ability to support dynamic power-saving operation at the AP; and the ability to send a frame to provide media protection for the AP's dynamic power-saving state transition.

[0018] In some embodiments, the processor is further configured to receive an acknowledgment frame from the AP in response to the second frame.

[0019] One aspect of this disclosure provides a computer-implemented method for wireless communication by an access point (AP) in a wireless network. The method includes operating in a first state of a dynamic power-saving mode. The method includes determining a capability to transition to a second state of the dynamic power-saving mode. The method further includes transitioning to the second state of the dynamic power-saving mode based on the determined capability during a Network Allocation Vector (NAV) duration.

[0020] In some embodiments, the first state is a reduced operating parameter state and the second state is an enhanced operating parameter state; the first state is an enhanced operating parameter state and the second state is a reduced parameter state; or the first state is a reduced operating parameter state without transmission capability and the second state is a reduced operating parameter state with transmission capability.

[0021] In some embodiments, the method further includes detecting a preamble to a frame that is not addressed to the AP, and the duration is associated with the frame.

[0022] In some embodiments, the method further includes: sending frames to set the NAV for at least the time period required to transition to the second state.

[0023] In some embodiments, the method further includes: sending a first frame to a station (STA) indicating that the AP intends to transition from a first state to a second state; and receiving a second frame from the STA in response to the first frame, the second frame including padding, wherein the AP transitions to the second state at or before the end of the padding.

[0024] In some embodiments, the method further includes: receiving a frame including padding from a station (STA), wherein the AP transitions to a second state at or before the end of the padding.

[0025] In some embodiments, frames are transmitted over the full bandwidth of the transmission opportunity (TXOP) or over the primary 20 MHz bandwidth of the TXOP.

[0026] In some embodiments, the method further includes: sending an acknowledgment frame to the STA in response to the frame. Attached Figure Description

[0027] Figure 1 An example of a wireless network according to an embodiment is shown.

[0028] Figure 2a An example of an AP according to an embodiment is shown.

[0029] Figure 2b An example of a STA according to an embodiment is shown.

[0030] Figure 3 An example of multi-link communication operation according to an embodiment is shown.

[0031] Figure 4 An EHT capability element according to an embodiment is shown.

[0032] Figure 5 An example of uplink frame exchange between a STA and an AP operating in DPS mode, according to an embodiment, is shown.

[0033] Figure 6 A general scenario is illustrated, according to an embodiment, in which an AP operation has a basic service set (BSS) with several associated STAs.

[0034] Figure 7a The illustration shows the use of a transmission opportunity (TXOP) not addressed to an AP to perform a transition from reduced operating parameters to enhanced operating parameters, according to an embodiment.

[0035] Figure 7b The example illustrates using a TXOP not addressed to an AP to perform a conversion from enhanced operating parameters to reduced operating parameters.

[0036] Figure 8a This illustrates, according to an embodiment, using Clear Send (CTS)-to-self (CTS to itself) as a TXOP holder to perform media protection for the transition from reduced operating parameters to enhanced operating parameters.

[0037] Figure 8b This illustrates, according to an embodiment, using Clear Send to itself (CTS) as a TXOP holder to provide media protection for the transition from enhanced operating parameters to reduced operating parameters.

[0038] Figure 9a The illustration shows the use of STA assistance for media protection during the transition from reduced operating parameters to enhanced operating parameters in the downlink TXOP, according to an embodiment.

[0039] Figure 9b The illustration shows the use of STA assistance for media protection during the transition from enhanced to reduced operating parameters in the downlink TXOP, according to an embodiment.

[0040] Figure 9c The illustration shows, according to an embodiment, media protection for the transition from enhanced operating parameters to reduced operating parameters after a non-AP STA performs downlink transmission using non-triggered transmission.

[0041] Figure 10 The illustration shows an indication of the intent of an AP in DPS mode to switch to another DPS state in the A control field, according to an embodiment.

[0042] Figure 11a Media protection for conversion-back reduction operation parameters is shown according to an embodiment for using subsequent frames after uplink transmission.

[0043] Figure 11b Media protection for conversion-back reduction operation parameters with padding after uplink transmission is shown according to an embodiment.

[0044] Figure 12a Media protection according to an embodiment is shown for switching from reduced operating parameters to enhanced operating parameters after uplink transmission.

[0045] Figure 12b Media protection according to an embodiment is shown for switching from reduced operating parameters to enhanced operating parameters after uplink transmission.

[0046] Figure 13 A flowchart illustrating an example process of the AP performing DPS state transitions according to an embodiment is shown.

[0047] Figure 14 A flowchart illustrating an example process performed by the STA when the AP performs a DPS state transition, according to an embodiment, is shown.

[0048] In one or more embodiments, not all components depicted in each figure are necessary, and one or more embodiments may include additional components not shown in the figures. Variations in the arrangement and type of components may be made without departing from the scope of this subject matter disclosure. Additional components, different components, or fewer components may be utilized within the scope of this subject matter disclosure. Detailed Implementation

[0049] The detailed description set forth below in conjunction with the accompanying drawings is intended to describe various embodiments and is not intended to represent the only embodiments in which the subject matter can be practiced. Rather, this detailed description includes specific details to provide a thorough understanding of the subject matter of the invention. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the scope of this disclosure. Therefore, the drawings and description are to be considered illustrative rather than restrictive in nature. The same reference numerals denote the same elements.

[0050] The following description pertains to certain implementations for the purpose of describing the innovative aspects of this disclosure. However, those skilled in the art will readily recognize that the teachings herein can be applied in a variety of different ways. The examples in this disclosure are based on WLAN communication in accordance with the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, including the IEEE 802.11be standard and any future revisions to the IEEE 802.11 standard. However, the described embodiments can be implemented in any device, system, or network capable of transmitting and receiving radio frequency (RF) signals according to the IEEE 802.11 standard, Bluetooth standard, Global System for Mobile Communications (GSM), GSM / General Packet Radio Service (GPRS), Enhanced Data GSM Environment (EDGE), Terrestrial Trunking Radio (TETRA), Wideband CDMA (W-CDMA), Evolved Data Optimized (EV-DO), 1xEV-DO, EV-DO Rev A, EV-DO Rev B, High-Speed ​​Packet Access (HSPA), High-Speed ​​Downlink Packet Access (HSDPA), High-Speed ​​Uplink Packet Access (HSUPA), Evolved High-Speed ​​Packet Access (HSPA+), Long Term Evolution (LTE), 5G NR (New Radio), AMPS, or other known signals used for communication within wireless, cellular, or Internet of Things (IoT) networks, such as systems utilizing 3G, 4G, 5G, 6G, or further implementations of their technologies.

[0051] Depending on the network type, other well-known terms may be used instead of "access point" or "AP," such as "router" or "gateway." For convenience, the term "AP" is used in this disclosure to refer to a network infrastructure component that provides wireless access to remote terminals. In a WLAN, assuming that the AP also contends for the wireless channel, the AP may also be referred to as a STA. Furthermore, depending on the network type, other well-known terms may be used instead of "station" or "STA," such as "mobile station," "subscriber station," "remote terminal," "user equipment," "wireless terminal," or "user device." For convenience, the terms "station" and "STA" are used in this disclosure to refer to a remote wireless device that wirelessly accesses an AP or contends for a wireless channel in a WLAN, whether the STA is a mobile device (such as a mobile phone or smartphone) or is generally considered a fixed device (such as a desktop computer, AP, media player, fixed sensor, television, etc.).

[0052] Multilink Operation (MLO) is a key feature currently being developed by the standards body for next-generation Ultra High Throughput (EHT) Wi-Fi systems in IEEE 802.11be. Wi-Fi devices that support MLO are called Multilink Devices (MLDs). Using MLO, a non-AP MLD can discover, authenticate, associate, and establish multiple links with an AP MLD. Channel access and frame switching can occur on each link between the AP MLD and non-AP MLDs.

[0053] Figure 1 An example of a wireless network 100 according to an embodiment is shown. Figure 1 The illustrated embodiment of the wireless network 100 is for illustrative purposes only. Other embodiments of the wireless network 100 may be used without departing from the scope of this disclosure.

[0054] like Figure 1 As shown, wireless network 100 may include multiple wireless communication devices. Each wireless communication device may include one or more stations (STAs). An STA may be a logical entity that is a separate addressable instance of an interface to the Media Access Control (MAC) layer and Physical (PHY) layer of the wireless medium. STAs may be classified as Access Point (AP) STAs and Non-Access Point (Non-AP) STAs. An AP STA may be an entity that provides access to distribution system services to an associated STA via the wireless medium. A Non-AP STA may be a STA not included within an AP-STA. For simplicity, an AP STA may be referred to as an AP, and a Non-AP STA may be referred to as a STA. Figure 1In the example, AP 101 and AP 103 are wireless communication devices, each of which may include one or more AP STAs. In such an embodiment, AP 101 and AP 103 may be AP multilink devices (MLDs). Similarly, STAs 111-114 are wireless communication devices, each of which may include one or more non-AP STAs. In such an embodiment, STAs 111-114 may be non-AP MLDs.

[0055] AP 101 and AP 103 communicate with at least one network 130, such as the Internet, a proprietary Internet Protocol (IP) network, or other data network. AP 101 provides wireless access to network 130 to multiple stations 111-114 in the coverage area 120 of AP 101. AP 101 and AP 103 can communicate with each other and with STAs using Wi-Fi or other WLAN communication technologies.

[0056] Depending on the network type, other well-known terms may be used instead of "access point" or "AP," such as "router" or "gateway." For convenience, the term "AP" is used in this disclosure to refer to a network infrastructure component that provides wireless access to remote terminals. In a WLAN, assuming that the AP also contends for the wireless channel, the AP may also be referred to as a STA. Furthermore, depending on the network type, other well-known terms may be used instead of "station" or "STA," such as "mobile station," "subscriber station," "remote terminal," "user equipment," "wireless terminal," or "user device." For convenience, the terms "station" and "STA" are used in this disclosure to refer to a remote wireless device that wirelessly accesses an AP or contends for a wireless channel in a WLAN, whether the STA is a mobile device (such as a mobile phone or smartphone) or is generally considered a fixed device (such as a desktop computer, AP, media player, fixed sensor, television, etc.).

[0057] exist Figure 1 In the diagram, the dashed lines indicate the approximate extent of coverage areas 120 and 125 of AP 101 and AP 103, which are shown as approximately circular for illustrative and explanatory purposes. It should be clearly understood that, depending on the configuration of the APs, the coverage areas associated with the APs (such as coverage areas 120 and 125) may have other shapes, including irregular shapes.

[0058] As described in more detail below, one or more APs in an AP may include circuitry and / or programming for managing MU-MIMO and OFDMA channel detection in a WLAN. Although Figure 1 An example of a wireless network 100 is shown, but more details can be found on other wireless networks. Figure 1Various modifications can be made. For example, wireless network 100 can include any number of APs and any number of STAs in any suitable arrangement. Furthermore, AP 101 can communicate directly with any number of STAs and provide them with wireless broadband access to network 130. Similarly, each AP 101 and AP 103 can communicate directly with network 130 and provide STAs with direct wireless broadband access to network 130. Additionally, AP 101 and / or AP 103 can provide access to other or additional external networks, such as external telephone networks or other types of data networks.

[0059] Figure 2a An example of AP 101 according to an embodiment is shown. Figure 2a The embodiment of AP 101 shown is for illustrative purposes, and Figure 1 AP 103 can have the same or similar configuration. However, APs have a wide variety of configurations, and Figure 2a This disclosure is not intended to limit the scope to any particular implementation of AP.

[0060] like Figure 2a As shown, AP 101 may include multiple antennas 204a-204n, multiple radio frequency (RF) transceivers 209a-209n, transmit (TX) processing circuitry 214, and receive (RX) processing circuitry 219. AP 101 may also include a controller / processor 224, a memory 229, and a backhaul or network interface 234. RF transceivers 209a-209n receive incoming RF signals from antennas 204a-204n, such as signals transmitted by STAs in network 100. RF transceivers 209a-209n down-convert the incoming RF signals to generate intermediate frequency (IF) or baseband signals. The IF or baseband signals are sent to RX processing circuitry 219, which generates processed baseband signals by filtering, decoding, and / or digitizing the baseband or IF signals. RX processing circuitry 219 sends the processed baseband signals to controller / processor 224 for further processing.

[0061] TX processing circuit 214 receives analog or digital data (such as voice data, network data, email, or interactive video game data) from controller / processor 224. TX processing circuit 214 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. RF transceivers 209a-209n receive the processed baseband or IF signal from TX processing circuit 214 and up-convert the baseband or IF signal into an RF signal transmitted via antennas 204a-204n.

[0062] The controller / processor 224 may include one or more processors or other processing devices that control the overall operation of the AP 101. For example, the controller / processor 224 may control the RF transceivers 209a-209n, the RX processing circuitry 219, and the TX processing circuitry 214 to receive uplink signals and transmit downlink signals, based on well-known principles. The controller / processor 224 may also support additional functions, such as more advanced wireless communication capabilities. For example, the controller / processor 224 may support beamforming or directional routing operations, where outgoing signals from multiple antennas 204a-204n are weighted differently to effectively direct outgoing signals in a desired direction. The controller / processor 224 may also support OFDMA operations, where outgoing signals are assigned to different subsets of subcarriers for different receivers (e.g., different STAs 111-114). The controller / processor 224 may support any of a variety of other functions in the AP 101, including combining DLMU-MIMO and OFDMA in the same transmission opportunity. In some embodiments, controller / processor 224 may include at least one microprocessor or microcontroller. Controller / processor 224 is also capable of executing programs and other processes, such as an operating system, residing in memory 229. Controller / processor 224 may move data into or out of memory 229 as needed by the executing process.

[0063] The controller / processor 224 is also coupled to a backhaul or network interface 234. The backhaul or network interface 234 allows the AP 101 to communicate with other devices or systems via a backhaul connection or over a network. Interface 234 can support communication via any suitable wired or wireless connection. For example, interface 234 can allow the AP 101 to communicate with a larger network (such as the Internet) via a wired or wireless local area network or via a wired or wireless connection. Interface 234 may include any suitable structure that supports communication via a wired or wireless connection, such as an Ethernet or RF transceiver. Memory 229 is coupled to the controller / processor 224. A portion of memory 229 may include RAM, and another portion of memory 229 may include flash memory or other ROM.

[0064] As described in more detail below, AP 101 may include circuitry and / or procedures for managing the channel detection process in a WLAN. Although Figure 2a An example of AP 101 is shown, but it is possible to compare it with other versions. Figure 2a Various changes can be made. For example, AP101 can include any number of... Figure 2aEach component shown. As a specific example, the AP may include multiple interfaces 234, and the controller / processor 224 may support routing functionality to route data between different network addresses. As another example, although shown as a single instance including TX processing circuitry 214 and a single instance including RX processing circuitry 219, AP 101 may include multiple instances of each (e.g., one for each RF transceiver). Alternatively, only one antenna and RF transceiver path may be included, as in a conventional AP. Moreover, Figure 2a The various components can be combined, further subdivided, or omitted, and additional components can be added as needed.

[0065] like Figure 2a As shown, in some embodiments, AP 101 may be an AP MLD comprising multiple APs 202a-202n. Each AP 202a-202n is attached to AP MLD 101 and includes multiple antennas 204a-204n, multiple radio frequency (RF) transceivers 209a-209n, transmit (TX) processing circuitry 214, and receive (RX) processing circuitry 219. Each AP 202a-202n may communicate independently with the controller / processor 224 and other components of AP MLD 101. Figure 2a The diagram shows that each AP 202a-202n has multiple antennas individually, but each AP 202a-202n can share multiple antennas 204a-204n without requiring separate multiple antennas. Each AP 202a-202n can represent the physical (PHY) layer and the lower media access control (MAC) layer.

[0066] Figure 2b An example of STA 111 according to an embodiment is shown. Figure 2b The embodiment of STA 111 shown is for illustrative purposes, and Figure 1 STAs 111-114 can have the same or similar configurations. However, STAs appear in a wide variety of configurations, and Figure 2b This disclosure is not intended to limit the scope to any particular implementation of STA.

[0067] like Figure 2b As shown, STA 111 may include one or more antennas 205, an RF transceiver 210, a TX processing circuit 215, a microphone 220, and an RX processing circuit 225. STA 111 may also include a speaker 230, a controller / processor 240, an input / output (I / O) interface (IF) 245, a touchscreen 250, a display 255, and a memory 260. The memory 260 may include an operating system (OS) 261 and one or more applications 262.

[0068] RF transceiver 210 receives incoming RF signals transmitted by the AP of network 100 from antenna 205. RF transceiver 210 down-converts the incoming RF signals to generate IF or baseband signals. The IF or baseband signals are sent to RX processing circuitry 225, which generates processed baseband signals by filtering, decoding, and / or digitizing the baseband or IF signals. RX processing circuitry 225 sends the processed baseband signals to speaker 230 (e.g., for voice data) or to controller / processor 240 for further processing (e.g., for web browsing data).

[0069] TX processing circuitry 215 receives analog or digital voice data from microphone 220, or other outgoing baseband data (such as web data, email, or interactive video game data) from controller / processor 240. TX processing circuitry 215 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. RF transceiver 210 receives the processed outgoing baseband or IF signal from TX processing circuitry 215 and up-converts the baseband or IF signal into an RF signal transmitted via antenna 205.

[0070] The controller / processor 240 may include one or more processors and executes a basic OS program 261 stored in memory 260 to control the overall operation of STA 111. In one such operation, the controller / processor 240 controls the RF transceiver 210, RX processing circuitry 225, and TX processing circuitry 215 to receive downlink signals and transmit uplink signals according to well-known principles. The controller / processor 240 may also include processing circuitry configured to provide management of the channel detection process in the WLAN. In some embodiments, the controller / processor 240 may include at least one microprocessor or microcontroller.

[0071] The controller / processor 240 is also capable of executing other processes and programs residing in the memory 260, such as operations for managing the channel sensing process in the WLAN. The controller / processor 240 can move data into or out of the memory 260 as needed by the executing processes. In some embodiments, the controller / processor 240 is configured to execute multiple applications 262, such as applications for channel sensing, including feedback calculations based on received Null Data Packet Advertisements (NDPA) and Null Data Packets (NDP), and sending beamforming feedback reports in response to trigger frames (TF). The controller / processor 240 can operate the multiple applications 262 based on the OS program 261 or in response to signals received from the AP. The controller / processor 240 is also coupled to an I / O interface 245, which provides the STA 111 with the ability to connect to other devices such as laptops and handheld computers. The I / O interface 245 is the communication path between these accessories and the main controller / processor 240.

[0072] The controller / processor 240 is also coupled to input 250 (e.g., a touchscreen) and display 255. An operator of STA 111 can use input 250 to input data into STA 111. Display 255 may be a liquid crystal display, a light-emitting diode display, or other display capable of displaying text and / or at least limited graphics (such as from a website). Memory 260 is coupled to the controller / processor 240. A portion of memory 260 may include random access memory (RAM), and another portion of memory 260 may include flash memory or other read-only memory (ROM).

[0073] although Figure 2b An example of STA 111 is shown, but it is possible to compare it with other models. Figure 2b Make various changes. For example, Figure 2b The various components can be combined, further subdivided, or omitted, and additional components can be added as needed. In a specific example, STA 111 may include any number of antennas 205 for MIMO communication with AP 101. In another example, STA 111 may not include voice communication, or the controller / processor 240 may be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). Furthermore, although... Figure 2b The STA 111 is shown configured as a mobile phone or smartphone, but the STA can be configured to operate as other types of mobile or fixed devices.

[0074] like Figure 2bAs shown, in some embodiments, STA 111 may be a non-AP MLD comprising multiple STAs 203a-203n. Each STA 203a-203n is attached to the non-AP MLD 111 and includes an antenna 205, an RF transceiver 210, a TX processing circuit 215, and an RX processing circuit 225. Each STA 203a-203n may independently communicate with the controller / processor 240 and other components of the non-AP MLD 111. Figure 2b It is shown that each STA 203a-203n has a separate antenna, but each STA 203a-203n can share antenna 205 without requiring a separate antenna. Each STA 203a-203n can represent the physical (PHY) layer and the lower medium access control (MAC) layer.

[0075] Figure 3 An example of multi-link communication operation according to an embodiment is shown. Multi-link communication operation can be used in the IEEE 802.11be standard and any future revisions of the IEEE 802.11 standard. Figure 3 In the middle, AP MLD 310 can be Figure 1 Wireless communication devices 101 and 103 are included, and the non-AP MLD 220 can be... Figure 1 One of the wireless communication devices 111-114 in the series.

[0076] like Figure 3 As shown, AP MLD 310 may include multiple auxiliary APs, such as AP 1, AP 2, and AP 3. Each auxiliary AP may include a PHY interface to the wireless medium (Link 1, Link 2, or Link 3). AP MLD 310 may include a single MAC Service Access Point (SAP) 318 through which the auxiliary APs of AP MLD 310 communicate with higher layers (Layer 3 or network layer). Each auxiliary AP of AP MLD 310 may have a different MAC address (lower MAC address) than any other auxiliary AP of AP MLD 310. AP MLD 310 may have an MLD MAC address (higher MAC address), and the auxiliary APs share a single MAC SAP 318 to Layer 3. Therefore, the auxiliary APs share a single IP address, and Layer 3 identifies AP MLD 310 by assigning a single IP address.

[0077] A non-AP MLD 320 may include multiple affiliated STAs, such as STA 1, STA 2, and STA 3. Each affiliated STA may include a PHY interface to the wireless medium (Link 1, Link 2, or Link 3). A non-AP MLD 320 may include a single MAC SAP 328, through which affiliated STAs communicate with higher layers (Layer 3 or network layer). Each affiliated STA of a non-AP MLD 320 may have a different MAC address (lower MAC address) than any other affiliated STA of the non-AP MLD 320. A non-AP MLD 320 may have an MLD MAC address (higher MAC address), and the affiliated STAs share the single MAC SAP 328 to Layer 3. Therefore, the affiliated STAs share a single IP address, and Layer 3 identifies the non-AP MLD 320 by assigning this single IP address.

[0078] AP MLD 310 and non-AP MLD 320 can establish multiple links between their associated APs and STAs. In this example, AP 1 and STA 1 can establish Link 1, operating in the 2.4 GHz band. Similarly, AP 2 and STA 2 can establish Link 2, operating in the 5 GHz band, and AP 3 and STA 3 can establish Link 3, operating in the 6 GHz band. Each link can independently enable channel access and frame exchange between AP MLD 310 and non-AP MLD 320, which can increase data throughput and reduce latency. When associated with an AP MLD on a set of links (link establishment), each non-AP device is assigned a unique Association Identifier (AID).

[0079] The entire contents of the following documents are incorporated herein by reference, as if fully set forth herein: 1) IEEE 802.11-2020, “Wireless LAN Media Access Control (MAC) and Physical Layer (PHY) Specification”; 2) IEEE 802.11ax-2021, “Wireless LAN Media Access Control (MAC) and Physical Layer (PHY) Specification”; and 3) IEEE P 802.11be / D5.0, “Wireless LAN Media Access Control (MAC) and Physical Layer (PHY) Specification”.

[0080] A wireless network station (STA) can be in one of two states: wake-up or sleep. In wake-up mode, the STA continuously monitors the channel and can send or receive packets. In sleep mode, the STA does not monitor the channel, for example, for power saving purposes.

[0081] Non-AP STAs can operate in one of two power management modes: Active mode and Power Saving (PS) mode. In Active mode, the STA receives and transmits frames at any time and remains awake. In Power Saving (PS) mode, the STA enters a wake-up state to receive or transmit frames, otherwise remains in sleep mode.

[0082] To allow power saving for non-AP STAs, existing standards support several power-saving methods that determine how a STA behaves in PS mode and how it switches between power-saving and active modes. These include Normal Power Saving (PS), Automatic Power Saving Delivery (APSD), Wireless Network Management (WNM) power saving, Power Saving Multi-Polling Mode, Spatial Multiplexing PS, Independent Basic Service Set (IBSS) power saving, Very High Throughput (VHT) Transmission Opportunity (TXOP) power saving, and Target Wake-Up Time (TWT).

[0083] When operating in various power-saving modes, STAs may be unable to sense the radio medium status or receive traffic. This can cause their Network Assignment Vector (NAV) to become outdated, and the STA may not maintain synchronization with the radio medium, which will be referred to herein as loss of medium synchronization. To prevent such loss of medium synchronization from affecting other transmissions in the network, the standard defines a medium synchronization recovery procedure that an STA that has lost medium synchronization can follow after being able to reliably sense the channel again. For example, after the completion of a transmission from another STA in a Non-Simultaneous Transmit and Receive (NSTR) pair. Specifically, the medium synchronization recovery procedure may involve the affected STA initializing a timer (which may be referred to as a MediumSyncDelay timer) and pursuing a more conservative channel access procedure until the timer expires or medium synchronization is restored, whichever occurs earlier. This conservative approach of initiating a transmission opportunity (TXOP) when a non-AP STA has MediumSyncDelay > 0 may involve: i) sending a request to transmit (RTS) as the first frame to obtain the TXOP; and ii) not attempting more than MSD_TXOP_MAX TXOP (default 1) and using a CCA_ED threshold equal to dot11MSDOFDMEDthreshold (default -72dBm).

[0084] Conservative channel access procedures used for STAs during MediumSyncDelay>0 can be inefficient and potentially very detrimental to their performance.

[0085] Many of the power-saving features mentioned above may not apply to access points (APs). To provide power-saving mechanisms for APs (and STAs) operating in wake-up mode, the IEEE 802.11-2020 standard defines a power-saving mechanism called "Operating Mode Change." By using Operating Mode Change, a STA can change its operating channel width (CW) and / or the maximum number of spatial streams (NSS) it can support. Therefore, a STA can save power by reducing the channel width or the number of spatial streams when needed. An AP or non-AP STA can change its RX operating mode by: i) sending an Operating Mode Notification frame, which can be a Very High Throughput (VHT) Action frame (Class 3 Management), ii) sending an Operating Mode Notification element within a beacon frame, (re)association request, or response frame, or iii) sending an Operating Mode (OM) control subfield or an EHT OM control subfield in the A control field of a Quality of Service (QoS) data, QoS empty, or Class 3 Management frame. Each STA can also send a Capability element to indicate the different channel widths, modulation and coding schemes (MCS), and number of spatial streams (NSS) supported by the STA.

[0086] Figure 4 An EHT capability element according to an embodiment is shown. In the Supported Channel Width Set field of the capability element, the STA indicates the different channel widths it supports. For the AP, this is a superset of the current BSS channel width indicated in the Operation element. The Supported MCS and NSS Set field of the capability element indicates the MCS and NSS that can be supported at each CW. The encodings for VHT, HE, and EHT are completely different.

[0087] For HT, there is a 77-bit bitmap, and if MCS i is supported, bit i is set to 1. These values ​​are common to all channel widths.

[0088] For VHT, the supported MCS for each NSS can be indicated in the range {0-7, 0-8, 0-9} within the 16-bit Supported MCS and NSS Set fields. These values ​​are common to all channel widths. The differences in NSS supported for each CW are identified from the "Supported Channel Width Set" + "Extended NSS CW Support" fields.

[0089] For HE, the “Tx / Rx HE-MCS Mapping” subfield of the “Supported HE MCS and NSS Sets” field in the HE capability element (similar to VHT) indicates the MCS that can be supported for each NSS. However, the mapping is separate for each bandwidth range.

[0090] For EHT, the maximum NSS for each MCS (for TX and RX) is indicated in the "EHT-MCS Mapping" subfield of the "Supported EHT MCS and NSS Sets" field of the EHT capability element. The indication is separate for each MCS range {0-9, 10-11, 12-13} and is different for each bandwidth.

[0091] The capability element is a "per-link indication" and is sent by a non-AP STA according to the following: mandatory inclusion in association or reassociation request frames sent by a non-AP STA; mandatory presence in probe request frames sent by a non-AP STA; or mandatory presence in TDLS discovery request / response frames.

[0092] The capability element is a "per-link indication" and is sent by the AP STA according to the following: mandatory inclusion in beacon frames sent by the AP; mandatory inclusion in association or reassociation response frames sent by the AP; or mandatory inclusion in probe response frames sent by the AP.

[0093] To improve channel access capability or spectral efficiency with limited hardware cost and power consumption, IEEE 802.11be also supports an operating mode for non-AP MLD devices called Enhanced Multi-Link Single Radio (EMLSR). In EMLSR mode, the non-AP device behaves like a single radio device, capable of performing channel sensing and basic packet reception simultaneously on multiple frequency bands or links (which may be referred to herein as EMLSR listening mode), but only performing reliable data communication on one link at a time. Therefore, by opportunistically selecting the link that wins channel contention for data communication, EMLSR can improve system spectral efficiency.

[0094] In the discussions of IEEE 802.11bn, the need to reduce power consumption on the AP side has been noted. To this end, several strategies have been discussed, including scheduling the periodic sleep duration of the AP, enabling cross-link AP wake-up requests, and achieving dynamic power saving of the AP by using EMLSR "listening" operations.

[0095] In some embodiments, to save power and minimize performance degradation of latency-sensitive services, the AP can operate in Dynamic Power Saving (DPS) mode. In DPS mode, the AP can operate with reduced capabilities by default, such as one or more of the following: reduced channel width, support for limited Physical Protocol Data Unit (PPDU) formats, reduced MCS and NSS sets, etc. The AP can operate with reduced receive capabilities, reduced transmit capabilities, or both. Operating with reduced capabilities allows the AP to save power. Without loss of generality, reduced channel width, limited PPDU formats, MCS sets, and NSS values ​​may be referred to herein as reduced operating parameters. The AP can indicate the reduced operating parameters to be applied during DPS mode operation. The STA can receive this indication from the AP and communicate with the AP according to the indicated reduced capabilities. However, upon receiving a request within a TXOP, the AP can increase one or more of its operating parameters, including supported bandwidth (BW), supported PPDU formats, MCS sets, and NSS sets, at least for the duration of the TXOP. Without loss of generality, this channel width and MCS and NSS values ​​may be referred to herein as enhanced operating parameters. Therefore, after sending a request to the AP to increase its capabilities, the TXOP holder can perform communication with enhanced operating parameters, including enhanced channel width, PPDU format, MCS, and NSS values ​​for the remainder of the TXOP. After the TXOP ends or after a predetermined amount of time from the end of the TXOP, the AP can return to its reduced operating parameters. In some embodiments, the STA holding the TXOP or the STA monitoring requests and responses during the TXOP can assume that the AP will remain in enhanced operating state for at least a predetermined amount of time. When operating in DPS mode, the AP may require a DPS fill delay to transition from reduced operating parameters to enhanced operating parameters, and a DPS transition delay for the reverse transition. These parameters can be indicated by the AP in its UHR capability element.

[0096] Figure 5 An example of uplink frame exchange between a STA and an AP operating in DPS mode, according to an embodiment, is shown. Specifically, Figure 5The diagram illustrates uplink frame exchange between a STA and an AP operating in DPS mode, where the STA requests the AP to switch to enhanced capability. As shown, the STA can send a request frame 501. Request frame 501 may include padding 503 for a DPS padding delay, which represents the time it may take for the AP to switch from reduced operating parameters to enhanced operating parameters. The AP can transmit an acknowledgment (ACK) frame 505, and the AP switches to operating with enhanced operating parameters. During the time the AP operates with enhanced operating parameters, the STA can send an uplink PPDU 507 and padding 509 for the DPS switching delay to allow the AP to switch from enhanced to reduced operating parameters. After padding 509, the AP switches to reduced operating parameters and sends an ACK frame 509 to the STA.

[0097] DPS mode can also be considered an extension of the AP's EMLSR operation or an extension of the AP's Enhanced Multi-Link Multi-Radio (EMLMR) operation, and some of the same notification frames can be reused.

[0098] Dynamic Power Saving (DPS) provides an AP with a power-saving mechanism that does not degrade the performance of latency-sensitive services and maintains compatibility with legacy equipment. When operating in DPS mode, the AP can frequently switch between reduced and enhanced operating parameter states, and vice versa. During such transitions, the AP may be unable to sense the radio medium status or receive services. This "blindness" can persist for the duration of DPS fill delay when switching from reduced to enhanced operating parameters, and for the duration of DPS transition delay when switching from enhanced to reduced operating parameters. When this transition occurs, it can cause the AP's Network Assignment Vector (NAV) to become outdated and may lead to loss of medium synchronization at the AP. Conservative channel access procedures during medium synchronization loss can be detrimental to the performance of the AP's Basic Service Set (BSS).

[0099] Figure 6A general scenario is illustrated where the AP operates with a number of associated STAs (Basic Service Sets, BSSs) according to an embodiment. As shown, some STAs may be UHR STA 601, and some may be conventional STAs 603 and 605. There may also be several unassociated STAs 607, which may be intended to be associated with AP 609 later. For reasons varying depending on the implementation, AP 609 may intend to reduce its operating parameters (such as channel width, number of spatial streams, physical protocol data unit format capabilities, etc.) for power saving purposes. However, in doing so, AP may also intend to limit the performance degradation of UHR STA 601 by being able to perform dynamic expansion of its operating parameters. As described herein, the terms "channel width" and "bandwidth" are used interchangeably. For this purpose, AP may decide to operate in Dynamic Power Saving (DPS) mode. The mechanism by which AP instructs DPS operating parameters and the process by which AP instructs a transition to DPS mode are beyond the scope of this disclosure.

[0100] This document describes transmission parameters for downlink and uplink transmissions according to this disclosure. In some embodiments, for downlink transmissions operating in DPS mode, the AP may use transmission parameters (e.g., bandwidth, NSS, MCS, etc.) that conform to the AP's reduced operating parameters and the ability to receive STAs. In some embodiments, for downlink transmissions operating in DPS mode, the AP may internally decide whether it wants to operate with enhanced or reduced operating parameters, which may be referred to herein as the current operating parameters. Thus, when winning a transmission opportunity, the AP may send a frame with transmissions conforming to the current AP operating parameters and the ability to receive STAs. In some embodiments, the AP may use transmission parameters (bandwidth, NSS, MCS, etc.) that conform to the AP's reduced operating parameters and the ability to receive STAs when the receiving STA is prior to a specific WiFi generation (e.g., prior to IEEE 802.11bn). In some embodiments, the AP may internally decide whether it wants to operate with enhanced or reduced operating parameters, and when winning a transmission opportunity, if the STA is after a specific WiFi generation (e.g., IEEE 802.11bn), it may send a frame with transmissions conforming to the current AP operating parameters and the ability to receive STAs.

[0101] In some embodiments, for uplink transmissions and triggered uplink transmissions, the STA can use transmission parameters conforming to the AP's reduced operating parameters by default. If the STA supports DPS operation and intends to use enhanced operating parameters for the remainder of frame switching transmissions, the STA can send a request frame to the AP to request a switch to enhanced capability. All subsequent frames switched during a Transport Opportunity (TXOP) can then be sent in accordance with the AP's enhanced operating parameters. This request frame may be referred to herein as a DPS wake-up request frame, and it can be sent at the start of a TXOP or at any time during a TXOP.

[0102] In some embodiments, if the STA knows that the AP is currently using other instructions to enhance its operating parameters, the STA can directly send a frame with parameters that conform to the AP's enhanced operating parameters (without sending a request frame).

[0103] In some embodiments, a non-AP STA can indicate whether it is capable of sending a request frame to an AP operating in DPS to transition to enhanced capabilities by setting the capability bit in the UHR capability element sent by the STA in the probe request and associated response frames to 1. Otherwise, the bit can be set to 0. This bit may be referred to, for example, as the DPS support subfield. In some embodiments, a non-AP STA can use a separate bit to indicate its capability to support media protection for APs transitioning between DPS states by setting the capability bit in the UHR capability element sent by the STA in the probe request and associated response frames to 1. This bit may be, for example, the DPS media protection support subfield.

[0104] As described herein, DPS operation may require frequent transitions of the AP's state between enhanced and reduced operating parameter states, and if not properly handled, these transitions may potentially lead to loss of media synchronization and packet failure at the AP. Several solutions to this problem are provided according to embodiments of this disclosure and are discussed herein. As described herein, the TXOP holder or TXOP initiator can be a device that has already obtained the right to transmit on the radio medium through a channel contention process. The TXOP responder can be a device addressed by a frame transmitted by the TXOP holder in a TXOP.

[0105] As described herein, the term "padding" can be used loosely and can refer to padding fields or any frame or element included in the transmission and not expected to be decoded by the receiver. This can include, for example, padding fields of trigger frames, packet extension fields, QoS frames with garbage bits, and other fields. In some embodiments, new padding elements can be defined that carry padding bits. This element can include one or more of the following: an element ID field, a length field, a duration field indicating the duration of the element, and a padding field. In some embodiments, the padding element can be included by the transmitter within the frame to provide the necessary padding.

[0106] This document describes a method for ensuring media synchronization during DPS state transitions by not acting as either a TXOP holder or a TXOP responder, according to this disclosure. In some embodiments, it may be assumed that the AP is neither a TXOP holder nor a TXOP responder. During a transition from a reduced operating parameter state to an enhanced operating parameter state or vice versa, the AP may be unable to sense the media state or receive traffic. When such a transition occurs, it may result in a loss of media synchronization at the AP.

[0107] In some embodiments, if the AP is initially in a reduced parameter state and intends to transition to an enhanced parameter state, the AP can perform the transition during the duration of the TXOP if it can detect the preamble of a frame that is not addressed and whose Network Allocation Vector (NAV) time is longer than the DPS padding delay. In some embodiments, it may be sufficient if the detected frame overlaps with the AP's primary 20MHz channel of its BSS.

[0108] Figure 7a This illustration demonstrates the use of a TXOP not addressed to the AP to perform a transition from reduced operating parameters to enhanced operating parameters according to an embodiment. As shown, the AP initially operates with reduced operating parameters 701 and detects a preamble to a PPDU 703 not addressed to the AP. The PPDU includes a NAV duration 707 longer than the DPS padding delay 705, and thus provides the DPS padding delay 705 to the time the AP may need to transition from reduced operating parameters 701 to enhanced operating parameters 709. Therefore, the AP transitions from reduced operating parameters 701 to enhanced operating parameters 707 after the DPS padding delay 705.

[0109] In some embodiments, the decision to use a PPDU (or a corresponding TXOP) to perform a DPS state transition may be based on one or more of the following: i) the physical layer (PHY) version format of the PPDU (non-HT / HT / VHT / HE / EHT / UHR, etc.); ii) the duration of the PPDU (e.g., as indicated in the L-SIG field); iii) the NAV set by the PPDU (e.g., as indicated in the PHY header or MAC header in HE+ format); iv) the BSS color of the PPDU; v) the TA and RA of the PPDU; or vi) the DPS padding delay value.

[0110] In some embodiments, after a PPDU is detected, if the remaining PPDU duration (e.g., after determining that the frame is erroneous or not addressed to the STA) is greater than the DPS padding delay, the AP can perform a transition. For any frame, after receiving the RA and TA in the MAC header, the receiving STA can determine that the PPDU is erroneous or not addressed to it. If the frame is in HE format or higher and comes from another BSS, the receiving STA can make a determination about whether the PPDU is erroneous or not addressed to the STA earlier based on the BSS color in the PHY header.

[0111] In some embodiments, after detecting a PPDU, if the remaining TXOP duration after verifying the NAV is greater than the DPS padding delay, the AP can perform a transition. For any frame, the receiver STA can determine that the NAV information is valid after performing an FCS check. If the frame is in HE format or higher, the receiver STA can determine this earlier based on the TXOP subfield in the PHY header.

[0112] In some embodiments where the AP is initially in an enhanced parameter state and intends to transition to a reduced parameter state, the AP can perform the transition during the duration of the TXOP if it can detect the preamble of a frame that is not addressed and whose Network Allocation Vector (NAV) time is longer than the DPS transition delay. In some embodiments, it may be sufficient if the detected frame overlaps with the AP's primary 20MHz channel of its BSS.

[0113] Figure 7bThis illustration demonstrates the use of a TXOP not addressed to the AP to perform a transition from enhanced operating parameters to reduced operating parameters according to an embodiment. As shown, the AP initially operates with enhanced operating parameters 7B01 and detects a preamble for a PPDU 7B03 not addressed to the AP. The PPDU includes a NAV duration 7B07 that is longer than the DPS transition delay 7B05, and thus provides a DPS transition delay 7B05 that represents the time the AP might need to transition from enhanced operating parameters 7B01 to reduced operating parameters 7B09. Therefore, the AP transitions from enhanced operating parameters 7B01 to reduced operating parameters 7B09 after a DPS transition delay 7B05.

[0114] In some embodiments, the decision to use a PPDU (or a corresponding TXOP) to perform a DPS state transition may be based on one or more of the following: i) the PHY version format of the PPDU (non-HT / HT / VHT / HE / EHT / UHR, etc.); ii) the duration of the PPDU (e.g., as indicated in the L-SIG field); iii) the NAV set by the PPDU (e.g., as indicated in the PHY header or MAC header in HE+ format); iv) the BSS color of the PPDU; v) the TA and RA of the PPDU; or vi) the DPS transition delay value.

[0115] In some embodiments, after a PPDU is detected, if the remaining duration of the PPDU after determining that the frame is erroneous or not addressed to the STA is greater than the DPS conversion delay, the AP may perform a conversion. For any frame, after receiving the Receiver Address (RA) and Transmitter Address (TA) in the Media Access Control (MAC) header, the receiving STA can determine that the PPDU is erroneous or not addressed to it. If the frame is in High Efficiency (HE) format or higher and originates from another BSS, the receiving STA can determine this slightly earlier based on the BSS color in the PHY header.

[0116] In some embodiments, after a PPDU is detected, the AP can perform a conversion if the remaining TXOP duration (after NAV verification) is greater than the DPS conversion delay. For any frame, the receiver STA can determine that the NAV information is valid after performing a Frame Check Sequence (FCS) check. If the frame is in High Efficiency (HE) format or higher, the receiver STA can determine this slightly earlier based on the TXOP subfield in the PHY header.

[0117] In some embodiments, the preamble of the PPDU may need to satisfy some additional constraints for the AP to use it to perform a conversion. Such constraints may be based on, for example, the BSS color of the PPDU, the signal power of the detected preamble, the format of the detected PPDU, the duration of the PPDU, the spatial reuse flag of the PPDU, etc. In some embodiments, the constraints may be: i) the BSS color of the preamble detected by the AP does not match the AP's BSS; ii) the BSS color of the preamble detected by the AP matches the AP's BSS; iii) the measured signal power of the PPDU's preamble is higher than a given threshold (e.g., -62dBm or -72dBm); v) the format of the first PPDU transmitted in the TXOP may be a non-HT format; or vi) the preamble of the PPDU can prevent spatial reuse on the TXOP. In some embodiments, a combination of constraints of the above types can be used to determine whether a PPDU (or its corresponding TXOP) can be used to perform a conversion. In some embodiments, an AP may not use such a TXOP to perform a state transition if one or more of the following conditions are met: 1) the AP allows non-primary channel access (NPCA) mechanisms in its BSS, 2) the TXOP is eligible for NPCA, and 3) the NPCA handover delay is insufficient for the AP to perform a state transition and also perform a channel handover to a non-primary channel.

[0118] In some embodiments, APs operating in DPS mode may also disable the use of space reuse mechanisms in their BSS. In some embodiments, APs operating in DPS mode may not support or participate in all or some of the multi-AP coordination mechanisms. In some embodiments, APs operating in DPS mode may not allow the use of NPCA in their BSS.

[0119] This document describes how to ensure media synchronization during DPS state transitions as a TXOP holder, according to this disclosure. In some embodiments described below, it may be assumed that the AP is a TXOP holder. During transitions from a reduced operating parameter state to an enhanced operating parameter state or vice versa, the AP may be unable to sense the media state or receive traffic. When such a transition occurs as a TXOP holder, it can lead to a loss of media synchronization at the AP and can also cause collisions with frames transmitted by other STAs.

[0120] In some embodiments, the AP may not perform the DPS state transition as a TXOP holder.

[0121] In some embodiments, it can be ensured that the AP can perform a listening operation during the conversion to prevent loss of media synchronization.

[0122] In some embodiments, it can be ensured that the DPS fill delay and / or DPS conversion delay of the AP is shorter than a predetermined threshold interval. This interval can be, for example, a DIFS interval or an SIFS interval.

[0123] In some embodiments, when an AP is initially in a reduced-parameter state and intends to transition to an enhanced-parameter state, after winning the TXOP, the AP can transmit a CTS-to-self frame in a non-HT format to set the Network Allocation Vector (NAV), the duration of which is at least the DPS padding delay after the CTS-to-self frame ends, during which time it can then transition to enhanced operating parameters. This process prevents associated STAs capable of eavesdropping on the AP from initiating transmissions to the AP during the transition, thereby preventing frame loss.

[0124] Figure 8a This illustration demonstrates how, according to an embodiment, the AP, as a TXOP holder, uses CTS-to-self to provide media protection for the transition from reduced operating parameters to enhanced operating parameters. As shown, the AP is initially in reduced operating parameter state 801 and intends to transition to enhanced operating parameter state 809. Upon winning the TXOP, the AP sends a CTS-to-self frame 803 in non-HT format to set the NAV duration 805 to the duration of at least the DPS fill delay 807 after the end of the CTS-to-self frame 803. Therefore, the AP transitions to enhanced operating parameters 809.

[0125] In some embodiments, instead of a CTS-to-self frame, a new frame can be defined to set the NAV for the transition. This new frame may be referred to herein as, for example, an unavailability indication frame, and may include an indication of the duration of AP unavailability. In some embodiments, this duration may be the same as or different from the NAV duration of the frame. The unavailability indication frame may also include a reason code for the unavailability, and / or an indication of the AP's capabilities during the unavailability period. Note that although the process is shown as Figure 8a The first operation in a TXOP is performed, but this can also be performed in the middle or at the end of the TXOP after some frame swapping has been completed. In some embodiments, the unavailability indication can be carried in the frame as a new element or a new field (e.g., unavailability indication A control field, etc.).

[0126] In some embodiments, when the AP is initially in enhanced parameter state and intends to transition to reduced parameter state, upon winning the TXOP, the AP can send a CTS-to-self frame in non-HT format on the primary 20MHz channel to set the Network Allocation Vector (NAV) for a duration exceeding at least the DPS transition delay after the end of the CTS-to-self frame. The AP can then transition to reduced operating parameters during this time. This process prevents associated STAs capable of eavesdropping on the AP from initiating transmissions to the AP during the transition, thus preventing frame loss.

[0127] Figure 8b This illustration demonstrates how, according to an embodiment, the AP, as the TXOP holder, uses CTS-to-self to provide media protection for the transition from enhanced to reduced operating parameters. As shown, the AP is initially in enhanced operating parameter state 8B01 and intends to transition to reduced operating parameter state 8B09. Upon winning the TXOP, the AP sends a CTS-to-self frame 8B03 in non-HT format to set the NAV duration 8B05 to at least the duration of the DPS transition delay 8B07 after the end of the CTS-to-self frame 8B03. Therefore, the AP transitions to reduced operating parameters 8B09.

[0128] In some embodiments, instead of the CTS-to-self frame, a new frame can be defined to set the NAV for the transition. This new frame may be referred to herein as, for example, an unavailability indication frame, and may include an indication of the duration of AP unavailability (which may be the same as or different from the NAV time of the frame), a reason code for the unavailability, and / or an indication of the AP's capabilities during the unavailability period. Note that although the process is shown as... Figure 8b The first operation in a TXOP is performed, but this can also be performed in the middle or at the end of a TXOP after some frame swapping has been completed. In some embodiments, the unavailability indication can be carried in the frame as a new element or a new field (e.g., unavailability indication A control field, etc.).

[0129] In some embodiments, when the AP is initially in a reduced parameter state and intends to transition to an enhanced parameter state, upon winning the TXOP, the AP may first send a frame to a non-AP STA that supports DPS operation, indicating the AP's intention to transition from reduced operating parameters to enhanced operating parameters. The sent frame may include indications of one or more of the following: i) an indication that the AP is requesting padding in a response frame; ii) an identifier of the non-AP STA from which it requested padding; iii) an indication of the reason for padding; iv) the required duration of padding; v) the AP's current DPS state; vi) the AP's new DPS state; or vii) the required transmission bandwidth for the response frame.

[0130] In some embodiments, in a response frame, the non-AP STA may include sufficient padding to protect the medium until the AP performs a conversion to enhanced operating parameters (DSP padding delay). The term padding, as used herein, may include any bits included in the STA that are not expected to be decoded by the AP.

[0131] In some embodiments, the frame can be a trigger frame, such as a Buffer Status Report Polling (BSRP) frame or a basic trigger frame. The trigger frame may have new fields within the common information field or special user information field, as well as other fields, to indicate that the AP is requesting padding in the response frame to support the DPS state transition. The AP may use the UL length field to indicate the duration of the required padding. The trigger frame can occupy up to the AP's reduced operating channel width bandwidth. Non-AP STAs in the response frame to the trigger frame may include sufficient padding to protect the channel until the AP performs the transition to enhanced operating parameters (DPS padding delay).

[0132] Figure 9a This illustration demonstrates media protection using the assistance of a STA for the transition from reduced operating parameters to enhanced operating parameters during a downlink TXOP, according to an embodiment. Note that although this process is shown herein as the first operation of the TXOP, it can also be performed in the middle or at the end of the TXOP after some frame switching has been completed. In some embodiments, frame switching following the transition within the TXOP can be limited to the TXOP bandwidth of the trigger frame. As shown, the AP is initially in reduced parameter state 901 and intends to transition to enhanced parameter state 903. Upon winning the TXOP, the AP may first transmit a trigger frame 905 to a non-AP STA supporting DPS operation, indicating the AP's intention to transition from reduced operating parameters to enhanced operating parameters. After SIFS, the AP receives a trigger response 907 with padding, which provides a DPS padding delay 909 to protect the channel until the AP performs the transition to enhanced operating parameters 903. During the time the AP operates with enhanced operating parameters 903, the AP transmits a downlink PPDU 911.

[0133] In some embodiments, when the AP is initially in an enhanced parameter state and intends to transition to a reduced parameter state, after winning the TXOP, the AP may first send a frame to a non-AP STA that supports DPS operation, indicating that the AP intends to transition from enhanced operating parameters to reduced operating parameters. The sent frame may include indications of one or more of the following: i) an indication that the AP is requesting padding in a response frame; ii) an identifier of the non-AP STA from which it requested padding; iii) an indication of the reason for padding; iv) the required duration of padding; v) the AP's current DPS state; vi) the AP's new DPS state; or vii) the required transmission bandwidth for the response frame.

[0134] In some embodiments, the non-AP STA in the response frame may include sufficient padding to protect the medium until the AP performs a conversion to reduced operating parameters (DSP conversion delay).

[0135] In some embodiments, the frame may be a trigger frame, such as a Buffer Status Report Polling (BSRP) frame or a basic trigger frame. The trigger frame may have new fields within a common information field or a special user information field to indicate that the AP is requesting padding in the response frame to support the DPS state transition. The AP may use a UL length field to indicate the duration of the required padding. In some embodiments, the trigger frame may occupy up to the AP's reduced operating channel width bandwidth. Non-AP STAs in the response frame to the trigger frame may include sufficient padding to protect the channel until the AP performs the transition to reduced operating parameters (DPS transition delay).

[0136] Figure 9b This illustration demonstrates media protection using STA assistance during the transition from enhanced to reduced operating parameters in a downlink TXOP, according to an embodiment. Note that although this process is shown here as the first operation of the TXOP, it can also be performed in the middle or at the end of the TXOP after some frame switching has been completed. In some embodiments, frame switching following the transition within the TXOP can be limited to the smaller of the TXOP bandwidth and the AP's reduced capability bandwidth. As shown, the AP is initially in the enhanced operating parameter state 9B01 and intends to transition to the reduced operating parameter state 9B03. Upon winning the TXOP, the AP may first send a trigger frame 9B05 to a non-AP STA supporting DPS operation, indicating the AP's intention to transition from enhanced to reduced operating parameters. After SIFS, the AP receives a trigger response 9B07 with padding, which provides a DPS transition delay 9B09 to protect the channel until the AP performs the transition to reduced operating parameters 9B03. During the time the AP operates with reduced operating parameters 9B03, the AP sends a downlink PPDU 9B11.

[0137] In some embodiments, if a STA with DPS capability expects the AP to perform a transition from reduced operating parameters to enhanced operating parameters or vice versa during a TXOP, the STA can automatically send a frame with sufficient padding to the AP to enable the handover, without the AP sending an explicit trigger frame. In some embodiments, new frames can be defined, which may carry padding and can be sent by the TXOP responder. In some embodiments, frames can be sent over the full bandwidth of the TXOP.

[0138] Figure 9c This illustration demonstrates media protection for the transition from enhanced to reduced operating parameters after downlink transmission using non-triggered transmission from a non-AP STA, according to an embodiment. As shown, the AP initially operates with enhanced operating parameters 9C01. During TXOP, the AP transmits a downlink PPDU 9C05, and after SIFS, receives a BA 9C07. After SIFS, the AP receives a frame 9C09 with padding to protect the media, which allows the AP to switch during the DPS transition delay 9C11 without sending an explicit trigger frame. Therefore, after the DPS transition delay 9C11, the AP transitions to reduced operating parameters 9C03, during which time the AP transmits an ACK frame 9C13 on the primary 20 MHz bandwidth.

[0139] In some embodiments, frames can be transmitted on the primary 20MHz bandwidth. After the transition, the AP can transmit an acknowledgment (ACK) frame for the new frame on the lesser of: (i) the TXOP bandwidth and (ii) the AP's current operating bandwidth, or it can transmit the ACK on the primary 20MHz channel. In some embodiments, the frame may not request an ACK response. Such a frame can be, for example, a new variant of an ACK frame or a block acknowledgment (BA) frame. Note that although this process... Figure 9c The operation is shown as the last operation of the TXOP, but it can also be performed in the middle of the TXOP or at the beginning of the TXOP after some frame swapping has been completed.

[0140] In some embodiments, the AP may indicate within the TXOP its intention to switch to reduced or enhanced operating parameters at the end of the TXOP. In some embodiments, the AP may also indicate one or more STAs requested by the AP to assist in protecting the medium when the AP switches from enhanced operating parameters to reduced operating parameters or vice versa. These STAs may be among STAs that have already indicated support for DPS operation. When the AP is the TXOP holder, such an indication may be included, for example, within the A control field of a trigger frame sent by the AP or a frame sent by the AP.

[0141] Figure 10This illustration shows an indication, according to an embodiment, of an AP in DPS mode's intention to transition to another DPS state in the A control field. The A control field may include a control ID field, a DPS state field, a next DPS state field, an AID12 field, a reserved field, and a padding field. The control ID field can provide control identifier information. The DPS state field can indicate the AP's current DPS state and can be set to 1 to indicate enhanced operating parameters and to 0 to indicate reduced operating parameters. The next DPS state field can indicate the AP's next DPS state after a TXOP of a transmission including A control. In some embodiments, if the DPS state and next DPS state fields are different, an AID12 subfield may be present in the A control field. Here, the STA requesting assistance can be identified by the 12 least significant bits of its associated ID indicated in the AID12 subfield. In some embodiments, where A control is transmitted in a separately addressed frame, the STA addressed to by the frame (as indicated in the MAC header) may be the STA from which the AP is requesting transition. Reserved fields may be reserved. In some embodiments, assuming the receiver knows the current DPS state, the current DPS state field and the next DPS state field may not exist, and the A control field is only included when a DPS state transition is requested.

[0142] In some embodiments, new elements or fields may be defined, which the AP may include in the frame, to indicate to one or more receiving non-AP STAs that the AP is requesting padding to transition to its DPS state in the following TXOP. In the first TXOP initiated by any addressed STA following this indication, the STA may include the necessary padding to assist the AP in transitioning its DPS state. Note that the state transition may occur in a different TXOP than the one in which the AP provided the indication.

[0143] Note that although the above procedures have been mentioned for the case where the AP is the TXOP initiator, all or some of these procedures can also be applied to the case where the AP is the TXOP responder. They can also be applied to the case where the AP is not the TXOP holder but the TXOP has been shared with the AP via a triggered TXOP sharing procedure.

[0144] This document describes how to ensure media synchronization during DPS transitions as a TXOP responder according to this disclosure. In some embodiments, it may be assumed that the AP is a TXOP responder. During a transition from a reduced operating parameter state to an enhanced operating parameter state or vice versa, the AP may be unable to sense the media state or receive traffic. When such a transition occurs as a TXOP responder, it may result in a loss of media synchronization at the AP and may also lead to the failure of transmissions initiated by other STAs addressed to the AP.

[0145] In some embodiments, the AP may not perform one or both of the DPS state transitions (enhancement to reduction or reduction to enhancement) as a TXOP responder.

[0146] In some embodiments, it can be ensured that the AP can perform a listening operation to prevent loss of media synchronization during the transition from enhanced operating parameters to reduced operating parameters.

[0147] In some embodiments, the DPS filling delay and / or DPS conversion delay of the AP can be ensured to be shorter than a predetermined threshold interval. This interval can be, for example, an SIFS or DIFS interval. In some embodiments, if the delay is shorter than the DIFS interval, the conversion can be performed at the end of the TXOP after sending an acknowledgment frame.

[0148] In some embodiments, when a non-AP STA (supporting DPS operation) initiates a transmission with an AP operating in DPS mode and anticipates that the AP will switch from enhanced capability to reduced capability at the end of the transmission, the non-AP STA may terminate its transmission, allowing the AP sufficient time to send an acknowledgment of the transmission (if necessary) and switch back to reduced capability before the TXOP ends (DPS transition delay). In some embodiments, after receiving an acknowledgment for any frame sent to the AP, the non-AP STA may also send an empty data packet, a new frame, or a DPS wake-up request frame, including sufficient MAC padding to protect the medium for the time (DPS transition delay) sufficient for the AP to switch back to reduced capability. In some embodiments, frames may be transmitted over the full bandwidth of the TXOP. In some embodiments, frames may be transmitted over the AP's primary 20MHz channel.

[0149] Figure 11aThis illustration shows media protection for switching back to reduced operating parameters after uplink transmission using subsequent frames, according to an embodiment. As shown, the AP operates in DPS mode, and the AP anticipates switching from enhanced operating parameters 1103 to reduced operating parameters 1105 at the end of the TXOP. Initially, the AP operates with reduced operating parameters 1101 and receives a DPS wake-up request frame 1107, which includes padding with a DPS padding delay to allow the AP to switch from reduced operating parameters to enhanced operating parameters 1103. After SIFS, the AP transmits an ACK frame 1111. After SIFS, the AP receives an uplink PPDU 1113. After SIFS, the AP transmits a BA 1115. The AP receives a padded frame 1117 from a non-AP STA to protect the media for a sufficient time (DPS switching delay 1119) for the AP to switch back to reduced operating capabilities. After switching to reduced capability, the AP can transmit an ACK frame for an empty data packet, new frame, or DPS wake-up request frame on the primary 20MHz channel or at the lesser of: (i) TXOP bandwidth and (ii) the AP's reduced operation bandwidth, or the frame may not request an ACK response. Note that although in Figure 11a The process is shown as the final operation of the TXOP, but it can also be performed in the middle of the TXOP or at the beginning of the TXOP after some frame swapping has been completed.

[0150] In some embodiments, the padding required for the conversion (DPS conversion delay) may be included only in the last frame sent by the TXOP holder to the AP. Accordingly, the AP may perform the conversion to the reduced operating parameters during the padding period and may send an acknowledgment on the primary 20MHz bandwidth, or on the smaller of (i) the TXOP bandwidth and (ii) the AP's reduced bandwidth (corresponding to the reduced operating parameters).

[0151] Figure 11bThe diagram illustrates the use of padding in uplink frames, according to an embodiment, to protect the medium when switching back to reduced operating parameters after uplink transmission. Note that the last frame here could also be an Aggregated MAC Protocol Data Unit (A-MPDU), and the padding could be provided by an empty MPDU included in the A-MPDU. Note that although this process is shown here as the final operation of a TXOP, it could also be performed in the middle of a TXOP or at the beginning of a TXOP after some frame switching has been completed. As shown, the AP operates in DPS mode, and the AP anticipates switching from enhanced operating parameters 11B03 to reduced operating parameters 11B05 at the end of the TXOP. Initially, the AP operates with reduced operating parameters 11B01 and receives a DPS wake-up request frame 11B07, which includes padding with a DPS padding delay 11B09, so that the AP can switch from reduced operating parameters 11B01 to enhanced operating parameters 11B03. After SIFS, the AP sends an ACK frame 11B11. After SIFS, the AP receives an uplink PPDU 11B13. The AP receives an MPDU frame 11B15 with padding from a non-AP STA to protect the medium within a time sufficient for the AP to switch back to reduced capability (DPS switching delay 11B17). After switching to reduced operation parameters 11B05, the AP may transmit a BA frame 11B19 on the primary 20MHz channel for empty data packets, new frames, or DPS wake-up request frames, or the lesser of (i) the TXOP bandwidth and (ii) the AP's reduced operation bandwidth, or the frame may not request an ACK response.

[0152] In some embodiments, when a non-AP STA (supporting DPS operation) initiates a transmission with an AP operating in DPS mode, and anticipates that the AP will transition from reduced capability to enhanced capability at the end of the transmission, the non-AP STA may terminate its transmission so that the AP has sufficient time to send a transmission acknowledgment (if necessary) and transition to enhanced capability (DPS padding delay) before the TXOP ends. In some embodiments, after receiving acknowledgment for any frame sent to the AP, the non-AP STA may also send an empty data packet, a new frame, or a DPS wake-up request frame, including sufficient MAC padding to protect the medium for the time (DPS padding delay) sufficient for the AP to transition to enhanced capability. In some embodiments, frames may be sent over the full bandwidth of the TXOP, such as... Figure 12a As depicted in the text.

[0153] Figure 12aThis illustration shows media protection using subsequent frames to transition from reduced operating parameters to enhanced operating parameters after uplink transmission, according to an embodiment. As shown, the AP operates with reduced operating parameters 1201, during which time the AP receives an uplink PPDU 1205. After SIFS, the AP transmits BA 1207. After SIFS, non-AP STAs transmit frames 1209 with padding to protect the media for a time sufficient for the AP to transition to enhanced operating parameters 1203 (DPS padding delay 1211). After transitioning to enhanced capability, the AP can transmit an ACK frame 1213.

[0154] In some embodiments, the padding required for the transition (DPS padding delay) may be included only in the last frame sent by the TXOP holder to the AP. Accordingly, the AP may perform the transition to enhanced operating parameters during the padding period and may send an acknowledgment over the primary 20MHz bandwidth or over the full TXOP bandwidth.

[0155] Figure 12b The illustration shows the use of padding in uplink frames according to an embodiment to protect the medium when transitioning from reduced operating parameters to enhanced operating parameters after uplink transmission. Note that the last frame here can also be an A-MPDU, and the padding can be provided by an empty MPDU included in the A-MPDU.

[0156] like Figure 12b As shown, the AP operates with reduced operating parameters 12B01, during which time the AP receives uplink PPDU 12B05. Non-AP STAs send MPDU 12B07 with padding to protect the medium within a time sufficient for the AP to transition to enhanced operating parameters 12B03 (DPS padding delay 12B11). After transitioning to enhanced operating parameters 12B03, the AP sends ACK frame 12B09.

[0157] In some embodiments, the AP may indicate within the TXOP its intention to switch to reduced or enhanced operating parameters at the end of the TXOP. The AP may also indicate one or more STA indications to assist the protection medium when the AP requests to switch from enhanced to reduced operating parameters or vice versa. These STAs may be among STAs that have already indicated support for DPS operation. When the AP is a TXOP responder, such indications may be included in a field of an acknowledgment frame sent by the AP. This may be helpful for non-AP STAs (supporting DPS operation) to determine whether the AP intends to switch to reduced capability midway or at the end of a transmission, and whether it assumes the STA will transmit empty packets, new frames, or DPS wake-up request frames.

[0158] Note that although the above procedures have been mentioned for the case where the AP is the TXOP responder, all or some of them can also be applied to the case where the AP is the TXOP initiator and a non-AP STA is performing a triggered uplink transmission. They can also be applied to the case where the AP is the TXOP holder but the TXOP has already been shared with a non-AP STA via a triggered TXOP sharing procedure.

[0159] This document describes the media protection mechanism to be selected according to this disclosure. In some embodiments, when an AP operating in DPS mode determines to perform a transition of its DPS state, it may have several options for protecting the media, including: i) waiting to sniff packets on the media on which it is neither a TXOP holder nor a responder; ii) waiting for an uplink frame from the relevant STA to perform a state transition as a TXOP responder; or iii) competing to win channel access as a TXOP holder and performing media protection, etc.

[0160] In some embodiments, each type of media protection mechanism may have different overheads in terms of reliability, power consumption, handover delay, etc. Accordingly, the AP can make an internally implementation-specific decision on the mechanism to use. In some embodiments, the AP can set a threshold time T and wait for that time to see if an air packet is present, which the AP can use to perform a state transition. If no such frame is observed, the AP can initiate contention for channel access for performing a state transition as a TXOP holder. In some embodiments, the AP can initiate contention for channel access immediately after determining that a DPS state transition is needed. If the medium becomes busy due to transmissions not directed to the AP, the AP can follow a media protection mechanism that is neither directed to the TXOP holder nor to the responder. If the medium becomes busy due to transmissions addressed to the AP, the AP can follow a media protection mechanism that is directed to the TXOP responder. If the AP wins the media contention, the AP can follow a media protection mechanism that is directed to the TXOP holder.

[0161] Figure 13 A flowchart illustrating an example process of an AP performing a DPS state transition according to an embodiment is shown. Although one or more operations are described or shown in a specific order, in other embodiments, the operations may be rearranged in a different order, which may include performing multiple operations in at least partially overlapping time periods. Figure 13 The flowchart depicted in the diagram illustrates the process in AP (such as...) Figure 3 The operations performed in the AP shown in the figure.

[0162] Specifically, Figure 13A flowchart is shown, illustrating a sequence of steps performed by the AP to change its DPS state without losing media synchronization. In process 1300, in operation 1301, the AP determines that a DPS state transition needs to be performed.

[0163] In operation 1303, the AP determines the mechanism to use for media synchronization protection. In some embodiments, when an AP operating in DPS mode determines to perform a transition of its DPS state, it may have several options for protecting the media, including i) waiting to sniff data packets on the medium on which it is neither a TXOP holder nor a responder, ii) waiting for an uplink frame from the relevant STA to perform a state transition as a TXOP responder, or iii) competing to win channel access and performing media protection as a TXOP holder, etc.

[0164] In operation 1305, if the AP is neither the TXOP holder nor the responder, the AP checks whether the TXOP meets the necessary criteria. In some embodiments where the AP is initially in a reduced parameter state and intends to transition to an enhanced parameter state, if the AP can detect the preamble of a frame that is not addressed and whose Network Allocation Vector (NAV) time is longer than the DPS padding delay, the AP can perform a transition during the duration of the TXOP. In some embodiments where the AP is initially in an enhanced parameter state and intends to transition to a reduced parameter state, if the AP can detect the preamble of a frame that is not addressed and whose Network Allocation Vector (NAV) time is longer than the DPS transition delay, the AP can perform a transition during the duration of the TXOP. In some embodiments, the PPDU preamble may need to satisfy certain constraints for the AP to use it to perform a transition. Such constraints may be based on, for example, the PPDU's BSS color, the signal power of the detected preamble, the format of the detected PPDU, the PPDU duration, the PPDU's spatial reuse flag, and other constraints.

[0165] In Operation 1307, if the AP is the TXOP holder, the AP sends an appropriate frame and / or requests assistance to protect the medium. In some embodiments where the AP is initially in a reduced-parameter state and intends to transition to an enhanced-parameter state, after winning the TXOP, the AP can transmit a CTS-to-self frame in a non-HT format to set the Network Allocation Vector (NAV), the duration of which is at least the DPS padding delay after the end of the CTS-to-self frame, during which time it can then transition to enhanced operating parameters. This process prevents associated STAs capable of eavesdropping on the AP from initiating transmissions to the AP during the transition, thereby preventing frame loss.

[0166] In some embodiments where the AP intends to change its DPS state, upon winning the TXOP, the AP may first send a frame to a non-AP STA that supports DPS operation, indicating that the AP intends to change its DPS state. The transmitted frame may include indications regarding one or more of the following: an indication that the AP requests padding in the response frame; the identifier of the non-AP STA requesting padding; an indication of the reason for padding; the required padding duration; the AP's current DPS state; the AP's new DPS state; or the required transmission bandwidth in the response frame. In the response frame, the non-AP STA may include sufficient padding to protect the medium until the AP performs a DPS state transition (DSP padding delay from reduced parameters to enhanced parameters and DPS transition delay from enhanced parameters to reduced parameters).

[0167] In operation 1309, if the AP is a TXOP responder, the AP sends an appropriate indication to the STA to request assistance to protect the medium (if needed). In some embodiments, when a non-AP STA (supporting DPS operation) initiates a transmission with an AP operating in DPS mode, and it is anticipated that the AP will change its DPS state at the end of the transmission, the non-AP STA may terminate its transmission so that the AP has sufficient time to send a transmission acknowledgment (if needed) and change the DPS state (DPS padding delay for the transition from reduced parameters to enhanced parameters and DPS transition delay for the transition from enhanced parameters to reduced parameters) before the TXOP ends.

[0168] In operation 1311, the AP performs DPS state transitions at appropriate time intervals.

[0169] In operation 1313, the AP sends one or more response frames, if applicable. In some embodiments, after a DPS state change, the AP may transmit an ACK frame for an empty data packet, a new frame, or a DPS wake-up request frame on the full bandwidth of the primary 20MHz channel or TXOP, or the frame may not request an ACK response.

[0170] Figure 14 A flowchart illustrating an example process of a DPS-enabled STA when an AP (associated with a DPS-enabled STA) performs a DPS state transition, according to an embodiment, is shown. Although one or more operations are described or shown in a specific order, in other embodiments, the operations may be rearranged in a different order, which may include performing multiple operations in at least partially overlapping time periods. Figure 14 The flowchart depicted in the diagram illustrates the process in STA (such as...) Figure 3 The operations performed in the STA shown in the figure.

[0171] In process 1400, during operation 1401, the STA performs frame exchange with the AP according to the DPS operation.

[0172] In operation 1403, if the STA is the TXOP holder and the AP has requested assistance from the STA for DPS state transition, the STA sends a frame with appropriate padding. In some embodiments, the non-AP STA may include sufficient padding in the frame to protect the medium until the AP performs a transition from reduced operating parameters to enhanced operating parameters (DSP padding delay) or a transition from enhanced operating parameters to reduced operating parameters (DPS transition delay).

[0173] In operation 1405, if the AP is the TXOP holder, the STA sends a response frame with appropriate padding upon receiving a trigger frame from the AP requesting assistance for media protection. In some embodiments, the non-AP STA may include sufficient padding in the frame to protect the media until the AP performs a transition from reduced operating parameters to enhanced operating parameters (DSP padding delay) or a transition from enhanced operating parameters to reduced operating parameters (DPS transition delay).

[0174] In operation 1407, if the STA is the TXOP holder and the AP is expected to perform a DPS state transition, the STA sends a frame with appropriate padding. In some embodiments, the non-AP STA may include sufficient padding in the frame to protect the medium until the AP performs a transition from reduced operating parameters to enhanced operating parameters (DSP padding delay) or from enhanced operating parameters to reduced operating parameters (DPS transition delay).

[0175] In operation 1409, if the AP is the TXOP holder and the AP is expected to perform a DPS state transition, the STA sends a frame with appropriate padding. In some embodiments, the non-AP STA may include sufficient padding in the frame to protect the medium until the AP performs a transition from reduced operating parameters to enhanced operating parameters (DSP padding delay) or from enhanced operating parameters to reduced operating parameters (DPS transition delay).

[0176] In operation 1411, if neither the STA nor the AP is a TXOP holder or responder, then the STA will avoid using space reuse and / or NPCA on the TXOP, if applicable.

[0177] In operation 1414, if applicable, the STA performs frame exchange with the AP according to the AP's new DPS state.

[0178] In some embodiments, when operating in a reduced capability state, the AP may have limited or no transmission capability. Accordingly, the AP may require some time to enable its transmitter, a phenomenon known as the DPS transmission delay. In some embodiments, this delay can be ensured to be less than the SIFS duration, allowing the AP to transmit a response frame within the SIFS duration of any frame addressed to it. In some embodiments, the mechanisms described above for transitioning as a TXOP holder, responder, or neither can be extended to consider three or more capability states. In some embodiments, these states may be: i) a reduced capability state with the transmitter off; ii) a reduced capability state with the transmitter on; or iii) an enhanced capability state with the transmitter on.

[0179] In some embodiments, if the sending capability is unavailable at the AP in DPS state, the AP may use a mechanism defined for TXOP responders or those who are neither TXOP holders nor responders to open the transmitter.

[0180] Embodiments of this disclosure may provide a mechanism to prevent loss of media synchronization at the AP during DPS state transitions, thereby improving wireless communication and allowing the AP to save power without degrading the performance of latency-sensitive services.

[0181] Unless otherwise specified, references to singular elements are not intended to indicate one and only one, but rather one or more. For example, a “one” module can refer to one or more modules. In the absence of further constraints, elements preceded by “a,” “an,” “the,” or “and” do not preclude the presence of additional identical elements.

[0182] Titles and subtitles (if any) are used for convenience only and do not limit the invention. The terms "exemplary" are used to indicate that they are intended as examples or illustrations. Within the scope of the use of terms such as "comprising," "having," etc., such terms are intended to be inclusive in a manner similar to the term "comprising," as "comprising" is interpreted as a conversion word in the claims. Relational terms such as "first" and "second" may be used to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between these entities or actions.

[0183] Phrases such as aspect, that aspect, on the other hand, some aspects, one or more aspects, implementation, that implementation, another implementation, some implementations, one or more implementations, embodiment, that embodiment, another embodiment, some embodiments, one or more embodiments, configuration, that configuration, another configuration, some configurations, one or more configurations, subject matter, disclosure, this disclosure, other variations thereof, etc., are used for convenience and do not imply that disclosures associated with such phrases are essential to the subject matter, or that such disclosures apply to all configurations of the subject matter. Disclosures associated with such phrases may apply to all configurations or one or more configurations. Disclosures associated with such phrases may provide one or more examples. Phrases such as aspect or some aspects may refer to one or more aspects, and vice versa, and this similarly applies to other foregoing phrases.

[0184] The phrase "at least one" following a series of items, along with the terms "and" or "or" used to separate any items, modifies the list as a whole, rather than each member of the list. The phrase "at least one of..." does not require the selection of at least one item; rather, it allows for the inclusion of at least one of any one item, and / or at least one of any combination of items, and / or at least one of each item. For example, each of the phrases "at least one of A, B, and C" or "at least one of A, B, or C" refers to only A, only B, or only C; any combination of A, B, and C; and / or at least one of each of A, B, and C.

[0185] It should be understood that the specific order or hierarchy of the disclosed steps, operations, or processes is an illustration of exemplary methods. Unless otherwise expressly stated, it should be understood that the specific order or hierarchy of steps, operations, or processes may be performed in a different order. Some steps, operations, or processes may be performed simultaneously, or may be performed as part of one or more other steps, operations, or processes. The appended method claims (if any) present elements of various steps, operations, or processes in a sample order, but this does not imply limitation to the specific order or hierarchy presented. These may be performed serially, linearly, in parallel, or in different orders. It should be understood that the described instructions, operations, and systems can generally be integrated together in a single software / hardware product or packaged into multiple software / hardware products.

[0186] This disclosure is provided to enable any person skilled in the art to practice the various aspects described herein. In some cases, well-known structures and components are shown in block diagram form to avoid obscuring the concept of the subject matter. This disclosure provides various examples of the subject matter, and the subject matter is not limited to these examples. Various modifications to these aspects will be apparent to those skilled in the art, and the principles described herein can be applied to other aspects.

[0187] All elements of the various aspects described herein, and all structural and functional equivalents known now or hereafter to those skilled in the art, are expressly incorporated herein by reference and are intended to be covered by the claims. Furthermore, nothing disclosed herein is intended to be made public, whether or not such disclosure is explicitly stated in the claims.

[0188] The title, background information, description of the drawings, abstract, and figures are incorporated herein by reference and are provided as illustrative examples rather than as limiting descriptions. It should be understood at the time of filing that they are not intended to limit the scope or meaning of the claims. Furthermore, in the detailed description, it will become apparent that the description provides illustrative examples and that various features are combined in various embodiments for the purpose of simplifying the disclosure. The approach of this disclosure should not be construed as reflecting an intention to require more features than expressly recited in each claim. Rather, as reflected in the following claims, the inventive subject matter lies in all features of fewer than those in a single disclosure configuration or operation. The appended claims are incorporated herein by reference, wherein each claim is independently claimed as a separate subject matter.

[0189] The claims are not intended to be limited to the aspects described herein, but rather to conform to the full scope consistent with the language claims and to include all legal equivalents. Nevertheless, no claim is intended to include subject matter that does not meet the requirements of applicable patent law, nor should they be interpreted in this manner.

Claims

1. An access point (AP) in a wireless network, comprising: Memory; and A processor coupled to the memory, the processor being configured to: Operates in the first state of dynamic power saving mode; The ability to determine the second state of the dynamic power-saving mode; and During the duration of the Network Assignment Vector (NAV), the system transitions to a second state of the dynamic power-saving mode based on the determined capabilities.

2. The AP according to claim 1, wherein: The first state is the state of reducing operating parameters, and the second state is the state of increasing operating parameters; The first state is the enhanced operation parameter state, and the second state is the reduced parameter state; or The first state is the reduced operation parameter state without the ability to send data, and the second state is the reduced operation parameter state with the ability to send data.

3. The AP according to claim 1, wherein, The processor is also configured to: The preamble of a frame that is not addressed to the AP is detected, and the duration of the NAV is associated with the frame.

4. The AP according to claim 1, wherein, The processor is also configured to: Frames are sent to set the NAV for at least the time period required to transition to the second state.

5. The AP according to claim 1, wherein, The processor is also configured to: Send a first frame to the station (STA) indicating that the AP intends to transition from the first state to the second state; and The STA receives a second frame in response to the first frame, the second frame including padding, wherein the AP transitions to a second state at or before the end of the padding.

6. The AP according to claim 1, wherein, The processor is also configured to: The slave station (STA) receives a frame including padding, wherein the AP transitions to a second state at or before the end of padding.

7. The AP according to claim 6, wherein, The frame is transmitted over the full bandwidth of the transmission opportunity (TXOP) or over the primary 20 MHz bandwidth of the TXOP.

8. The AP according to claim 6, wherein, The processor is also configured to: Send an acknowledgment frame in response to the frame to the STA.

9. The AP according to claim 1, wherein, The processor is also configured to: Apply one or more transmission parameters associated with the current state to which the AP belongs.

10. A station (STA) in a wireless network, comprising: Memory; and A processor coupled to the memory, the processor being configured to: Receive a first frame from the access point (AP), the first frame indicating that the AP intends to switch from a first state of dynamic power saving mode to a second state; and A second frame responding to the first frame is sent to the AP, the second frame including padding, wherein the AP transitions to a second state at or before the end of the padding.

11. The STA according to claim 10, wherein, The processor is also configured to send a third frame to the AP to indicate one or more of the following: Supports the ability to perform dynamic power-saving operations at the AP; and The ability to send frames that provide media protection for the dynamic power-saving state transitions of the AP.

12. The STA according to claim 10, wherein, The processor is also configured to: Receive an acknowledgment frame in response to the second frame from the AP.

13. A computer-implemented method for performing wireless communication by an access point (AP) in a wireless network, the method comprising operations performed by at least a processor in the AP according to any one of claims 1 to 9.

14. A computer-implemented method for performing wireless communication by a station (STA) in a wireless network, the method comprising operations performed by at least a processor in an AP according to any one of claims 10 to 12.

15. A non-transitory computer-readable storage medium storing instructions that, when executed individually or jointly by at least one processor of an access point (AP) in a wireless network, cause the AP to perform one or more operations as described in any one of claims 1 to 9.

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