Flexible restricted target wake-up time operation

Abstract

Methods and apparatus for facilitating TWT operation between devices in a wireless local area network. A non-access point (AP) multi-link device (MLD) includes a processor and stations (STAs), each STA including a transceiver configured to form a link with an AP affiliated to the AP MLD. A first one of the transceivers is further configured to transmit to or receive from the AP MLD a target wakeup time (TWT) information frame supporting multi-link operation (MLO) on a first one of the links, the TWT information frame including an indication of pausing or resuming a TWT service period (SP) on a second one of the links. The processor is operably coupled to the transceivers and is configured to suspend or restore the TWT SP on the second link based on the TWT information frame being successfully transmitted or received on the first link.

Description

Technical Field

[0001] The present disclosure generally relates to power management in wireless communication systems including multi-link devices. Embodiments of the present disclosure relate to methods and apparatus for enhancing target wake-up time operations in wireless local area network communication systems. Background Art

[0002] Wireless Local Area Network (WLAN) technology allows devices to access the Internet in the 2.4GHz, 5GHz, 6GHz, or 60GHz frequency bands. WLAN is based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. The IEEE 802.11 family of standards is designed to increase speed and reliability and extend the operating range of wireless networks.

[0003] The next generation of extremely high throughput (EHT) WI-FI systems (e.g., IEEE 802.11be) supports multiple operating bands (called links) through which access points (APs) and non-AP devices can communicate with each other. Therefore, both APs and non-AP devices are able to communicate on different bands / links, which is called multi-link operation (MLO). WI-FI devices that support MLO are called multi-link devices (MLDs). Using MLO, non-access point (non-AP) MLDs can discover, authenticate, associate, and establish multiple links with AP MLDs. On each link established between AP MLDs and non-AP MLDs, channel access and frame exchange are possible. The component of the MLD responsible for transmission and reception on a link is called a station (STA).

[0004] Target Wake Time (TWT) is one of the most important features of power management in WI-FI networks, which was developed by IEEE802.11ah and later adopted and modified to IEEE 802.11ax. With TWT operation, it is sufficient for the STA to wake up only at a pre-scheduled time negotiated with another STA or AP in the network. In the IEEE 802.11ax standard, two types of TWT operations are possible: individual TWT operation and broadcast TWT operation. A separate TWT agreement can be established between two STAs or between a STA and an AP. On the other hand, with broadcast TWT operation, the AP can set up a shared TWT session for a group of STAs.

[0005] Restricted TWT (rTWT or r-TWT) operation is a newly introduced feature in IEEE 802.11be (WI-FI 7), which provides more protection for STAs scheduled with restricted TWT to serve delay-sensitive applications in a timely manner. Restricted TWT is based on the broadcast TWT mechanism, however, there are some key characteristics that make restricted TWT operation an important feature for supporting low-latency applications in next-generation WLAN systems. Restricted TWT provides protected service periods for its member STAs by sending silent elements to other STAs in the basic service set (BSS) that are not members of the rTWT schedule, where the silent interval corresponding to the silent element overlaps with the initial part of the restricted TWT service period (SP). Therefore, it gives more channel access opportunities to STAs scheduled with rTWT members, which helps delay-sensitive business flows. Summary of the invention

[0006] Various embodiments of the present disclosure provide methods and apparatus for facilitating improved TWT operations between devices in a WLAN.

[0007] In one embodiment, a non-AP MLD is provided, which includes a STA and a processor operably coupled to the STA. Each STA includes a transceiver, which is configured to form a link with an AP attached to the AP MLD, respectively. The first transceiver among these transceivers is further configured to send or receive a TWT information frame supporting multi-link operation (MLO) to the AP MLD on a first link among these links, and the TWT information frame includes an indication to suspend or resume the TWT SP on a second link among these links. The processor is operably coupled to these transceivers and is configured to suspend or resume the TWT SP on the second link based on the TWT information frame being successfully sent or received on the first link.

[0008] In one embodiment, an AP MLD is provided, which includes an AP and a processor operably coupled to the AP. The AP includes transceivers configured to form links with STAs attached to non-AP MLDs, respectively. A first transceiver among the transceivers is further configured to send or receive a TWT information frame supporting multi-link operation (MLO) to or from the non-AP MLD on a first link among the links, the TWT information frame including an indication of pausing or resuming the TWT SP on a second link among the links. The processor is operably coupled to the transceivers and is configured to suspend or resume the TWT SP on the second link based on the TWT information frame being successfully sent or received on the first link.

[0009] In one embodiment, a method for wireless communication performed by a non-AP MLD including a STA is provided. The method includes the following steps: sending or receiving a TWT information frame supporting MLO including an indication of suspending or resuming the TWT SP on the second link of the links formed between the STA and the AP attached to the AP MLD to the AP MLD, and suspending or resuming the TWT SP on the second link based on the TWT information frame being successfully sent or received on the first link.

[0010] Other technical features may be apparent to those skilled in the art from the following drawings, descriptions and claims.

[0011] Before the following detailed description, it may be advantageous to set forth the definitions of certain words and phrases used throughout this patent document.The term "coupling" and its derivatives refer to any direct or indirect communication between two or more elements, whether or not these elements are in physical contact with each other.The terms "send", "receive" and "communication" and their derivatives include direct and indirect communication.The terms "include" and "comprise" and their derivatives mean including but not limited to this.The term "or" is inclusive, meaning and / or.The phrase "associated with..." and its derivatives mean including, included in, interconnected with, included in, connected to or connected with, coupled to or coupled with, can communicate with, collaborate with, interweave, juxtapose, be close to, be bound to or bound with, have, have the property of, have a relationship with, etc.The term "controller" means any device, system or part thereof that controls at least one operation.Such a controller can be implemented with hardware or a combination of hardware and software and / or firmware. Functionality associated with any particular controller may be centralized or distributed, whether local or remote. When used with a list of items, the phrase "at least one of..." means that different combinations of one or more of the listed items may be used, and only one item in the list may be required. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C. As used herein, terms such as "first" and "second" or "first" and "second" may be used to simply distinguish a corresponding component from another component, and do not limit the component in other aspects (e.g., importance or order). It should be understood that if an element (e.g., a first element) is referred to as "coupled with another element (e.g., a second element)", "coupled to another element", "connected to another element", or "connected to another element" with or without the term "operably" or "communicatively", it means that the element may be coupled to another element directly (e.g., wired), wirelessly, or via a third element.

[0012] As used herein, the term "module" may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with other terms (e.g., "logic," "logic block," "component," or "circuit"). A module may be a single integrated component or its smallest unit or portion suitable for performing one or more functions. For example, according to an embodiment, a module may be implemented in the form of an application specific integrated circuit (ASIC).

[0013] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classes, instances, related data or a portion thereof suitable for implementation in a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disc (DVD) or any other type of memory. "Non-transitory" computer-readable media does not include wired, wireless, optical or other communication links that transmit temporary electrical signals or other signals. Non-transitory computer-readable media include media that can permanently store data and media that can store data and rewrite data later, such as rewritable optical disks or erasable memory devices.

[0014] Definitions for certain other words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, wherein like reference numerals represent like parts:

[0016] Figure 1 An example wireless network according to one embodiment of the present disclosure is shown;

[0017] Figure 2a An example AP according to one embodiment of the present disclosure is shown;

[0018] Figure 2b An example STA according to one embodiment of the present disclosure is shown;

[0019] Figure 3 shows examples of different timing components related to a TWT SP according to an embodiment of the present disclosure;

[0020] Figure 4 An example format of a TWT information field in a TWT information frame of Table 1 according to an embodiment of the present disclosure is shown;

[0021] Figure 5 An example of a broadcast TWT schedule pause for a specific broadcast TWT schedule according to an embodiment of the present disclosure is shown;

[0022] Figure 6 An example of broadcast TWT schedule suspension for a specific broadcast TWT schedule while maintaining other broadcast TWT schedules according to an embodiment of the present disclosure is shown;

[0023] Figure 7 An example format of an EHT variant TWT information field including a broadcast TWT ID subfield according to an embodiment of the present disclosure is shown;

[0024] Figure 8 An example format of an EHT variant TWT information field including a negotiation type subfield according to an embodiment of the present disclosure is shown;

[0025] Fig. 9 An example format of a broadcast TWT information field according to an embodiment of the present disclosure is shown;

[0026] Fig.10 An example format of an EHT variant TWT information field including a restricted TWT exclusion subfield according to an embodiment of the present disclosure is shown;

[0027] Fig.11 An example format of an EHT variant TWT information field including all restricted TWT subfields according to an embodiment of the present disclosure is shown;

[0028] Fig.12 An example format of an EHT variant TWT information field including all restricted TWT subfields when the negotiation type subfield is set to 0 and all TWT subfields are set to 0 according to an embodiment of the present disclosure is shown;

[0029] Fig.13 An example format of an EHT variant TWT information field including all restricted TWT subfields when the negotiation type subfield is set to 0 and all TWT subfields are set to 0 according to an embodiment of the present disclosure is shown;

[0030] Fig.14 An example format of an EHT variant TWT information field including all restricted TWT subfields according to an embodiment of the present disclosure is shown;

[0031] Fig.15 An example format of an EHT variant TWT information field that enables selective exclusion of restricted TWT scheduling using an rTWT scheduling exclusion information subfield according to an embodiment of the present disclosure is shown;

[0032] Fig.16 An example format of the generalized TWT information field of the general TWT information frame of Table 6 according to an embodiment of the present disclosure is shown;

[0033] Fig.17An example format of a TWT information set subfield according to an embodiment of the present disclosure is shown;

[0034] Fig.18 An example format of a generalized restricted TWT information field of a generalized restricted TWT information frame of Table 7 according to an embodiment of the present disclosure is shown;

[0035] Fig.19 shows an example format of the Restricted TWT Pause Information field of the Restricted TWT Pause Information frame of Table 8 according to an embodiment of the present disclosure;

[0036] Fig. 20 A flowchart illustrating example behavior of an AP in the context of using a restricted TWT pause information frame according to an embodiment of the present disclosure;

[0037] Fig.21 A flowchart illustrating example behavior of a non-APSTA in the context of using a restricted TWT pause information frame according to an embodiment of the present disclosure;

[0038] Fig. 22 An example format of the Generalized Restricted TWT Pause Information field of the Generalized Restricted TWT Pause Information frame of Table 10 according to an embodiment of the present disclosure is shown;

[0039] Fig.23 An example format of the MLO Support TWT Information field of the MLO Support TWT Information frame of Table 11 according to an embodiment of the present disclosure is shown; and

[0040] Fig.24 An example process for facilitating TWT operations between MLDs using MLO support TWT information frames according to one embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0041] Discussed below Figures 1 to 24 The various embodiments used to describe the principles of the present disclosure in this patent document are for illustration only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will appreciate that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0042] The various embodiments of the present disclosure recognize that, for individual TWT, there is a mechanism for suspending or resuming a specific individual TWT agreement followed by a TWT requester STA while maintaining other TWT agreements, and for suspending or resuming all individual TWT agreements followed by a TWT requester STA. For broadcast TWT, there is a mechanism for suspending or resuming all broadcast TWT schedules followed by STAs scheduled by the TWT. In addition, the various embodiments of the present disclosure recognize that a flexible TWT is a TWT whose value may or may not be selected from a set of available TWT values ​​in accordance with TWT negotiation. The flexible TWT value can be any positive value, regardless of the set of values ​​negotiated for the TWT.

[0043] The various embodiments of the present disclosure further recognize that, according to the current 802.11 specifications, although the TWT information frame can be used to pause and resume all broadcast TWT schedules followed by the STA of the broadcast TWT schedule, the TWT information frame cannot be used to pause or resume the broadcast TWT SP on a per-schedule basis. That is, if the STA of the broadcast TWT schedule is a member of multiple broadcast TWT schedules, it is currently impossible to pause a specific broadcast TWT schedule while maintaining other broadcast TWT schedules. In addition, in 802.11be, with the introduction of restricted TWT scheduling (which is a variant of broadcast TWT scheduling), it would be useful to better manage broadcast TWT scheduling or restricted TWT scheduling. Therefore, a mechanism for pausing and resuming specific broadcast or restricted TWT schedules while maintaining other TWT schedules would be useful.

[0044] Accordingly, various embodiments of the present disclosure provide a mechanism for selectively suspending a specific broadcast TWT schedule or a restricted TWT schedule of which the STA is a member while maintaining other TWT schedules.

[0045] The various embodiments of the present disclosure further recognize that, currently, when all TWT subfields in the TWT information field in the TWT information frame are set to 1, all individual TWT agreements or broadcast TWT schedules are indicated by the TWT information field of the TWT information frame as being intended to be suspended or resumed. That is, all individual TWT agreements or broadcast TWT schedules are currently intended to be suspended or resumed by the TWT information frame, and it is not possible to selectively exclude any specific individual TWT agreement or broadcast TWT schedule from the schedule or agreement group being suspended or resumed. This is not very advantageous for restricted TWT operations, because an r-TWT scheduled STA may have multiple broadcast TWT schedules and restricted TWT schedules, and for some purpose (e.g., power saving), the scheduled STA may want to suspend the broadcast TWT schedule, but may still want to maintain the r-TWT schedule for the purpose of low-latency services.

[0046] Accordingly, various embodiments of the present disclosure provide mechanisms for selectively excluding TWT agreements or schedules from all TWT suspensions.

[0047] The various embodiments of the present disclosure further recognize that the current flexible TWT feature is not available for broadcast TWT operations. For broadcast TWT, the next TWT subfield value can only be a value from the set of available values ​​negotiated for the TWT. Accordingly, the broadcast TWT scheduling AP or the broadcast TWT scheduled STA cannot set an arbitrary value in the next TWT, even if this is allowed for individual TWT operations. For r-TWT operations, it would be beneficial for the r-TWT scheduled STA to have the flexibility to set the next TWT value to any positive value (not necessarily one of the available TWT value set) as needed. This will facilitate any changes in business patterns without the need to negotiate a new r-TWT schedule with the r-TWT scheduling AP.

[0048] Accordingly, various embodiments of the present disclosure provide a mechanism for flexible TWT value selection utilizing broadcast TWT scheduling and restricted TWT scheduling.

[0049] The various embodiments of the present disclosure further recognize that the current TWT information frame is a unicast frame. It cannot be sent to multiple STAs at the same time. The r-TWT scheduling AP can be attached to the AP MLD, and for various reasons (e.g., power saving), the AP may want to disable the associated link for a specific time period. Currently, there is no way to use the TWT information frame to notify all or multiple STAs in the BSS of the event.

[0050] Therefore, embodiments of the present disclosure provide a mechanism for an AP attached to an AP MLD to notify multiple STAs in a BSS that the AP is temporarily disabling a link.

[0051] The various embodiments of the present disclosure further recognize that the current TWT information frame cannot operate at the MLD level. The MLD may want to suspend individual TWT agreements or broadcast TWT schedules on multiple links to save power. It would be beneficial to have a mechanism for indicating which of the multiple links between the AP MLD and the non-AP MLD the TWT information frame is intended for.

[0052] Accordingly, various embodiments of the present disclosure provide a mechanism for the MLD to indicate which link a particular TWT information frame is intended for.

[0053] Figure 1 An example wireless network 100 is shown according to one embodiment of the present disclosure. Figure 1 The embodiment of the wireless network 100 shown is for illustration only. Other embodiments of the wireless network 100 may be used without departing from the scope of the present disclosure.

[0054] The wireless network 100 includes APs 101 and 103. The APs 101 and 103 communicate with at least one network 130, such as the Internet, a proprietary Internet Protocol (IP) network, or other data network. The AP 101 provides wireless access to the network 130 for a plurality of STAs 111-114 within a coverage area 120 of the AP 101. The APs 101-103 may communicate with each other and with the STAs 111-114 using Wi-Fi or other WLAN communication technologies.

[0055] 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 a remote terminal. In a WLAN, assuming that the AP also contends for a wireless channel, the AP may also be referred to as a STA (e.g., APSTA). In addition, 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 remote wireless equipment 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 smart phone) or is generally considered to be a fixed device (such as a desktop computer, AP, media player, fixed sensor, TV, etc.). This type of STA may also be referred to as a non-AP STA.

[0056] In one embodiment of the present disclosure, each of the APs 101 and 103 and each of the STAs 111-114 may be an MLD. In such an embodiment, the APs 101 and 103 may be AP MLDs, and the STAs 111-114 may be non-AP MLDs. Each MLD is attached to more than one STA. For ease of explanation, an AP MLD is described herein as being attached to more than one AP (e.g., more than one AP STA), and a non-AP MLD is described herein as being attached to more than one STA (e.g., more than one non-AP STA).

[0057] Dashed lines illustrate the approximate extents of coverage areas 120 and 125, which are shown as approximately circular for purposes of illustration and explanation only. It should be clearly understood that coverage areas associated with APs, such as coverage areas 120 and 125, may have other shapes, including irregular shapes, depending on the configuration of the AP and variations in the radio environment associated with natural and man-made obstacles.

[0058] As described in more detail below, one or more of the APs may include circuitry and / or programming for facilitating improved TWT operations between devices in a WLAN. Figure 1 One example of a wireless network 100 is shown, but may be Figure 1 Various changes may be made. For example, the wireless network 100 may include any number of APs and any number of STAs in any suitable arrangement. In addition, the AP 101 may communicate directly with any number of STAs and provide these STAs with wireless broadband access to the network 130. Similarly, each AP 101-103 may communicate directly with the network 130 and provide the STAs with direct wireless broadband access to the network 130. In addition, the APs 101 and / or 103 may provide access to other or additional external networks (such as an external telephone network or other types of data networks).

[0059] Figure 2a An example AP 101 is shown according to one embodiment of the present disclosure. Figure 2a The embodiment of AP 101 shown in FIG. 1 is for illustration only, and Figure 1 The APs 103 of FIG. 104 may have the same or similar configurations. In the embodiments discussed below, the AP 101 is an AP MLD. However, the APs have a variety of configurations, and Figure 2a The scope of the present disclosure is not limited to any particular implementation of the AP.

[0060] The AP MLD 101 is attached to a plurality of APs 202a-202n (which may be referred to as, for example, AP1-APn). Each of the attached APs 202a-202n includes a plurality of antennas 204a-204n, a plurality of RF transceivers 209a-209n, a transmit (TX) processing circuit 214, and a receive (RX) processing circuit 219. The AP MLD 101 also includes a controller / processor 224, a memory 229, and a backhaul or network interface 234.

[0061] The illustrated components of each subordinate AP 202a-202n may represent the physical (PHY) layer and the lower media access control (LMAC) layer in the open systems interconnection (OSI) networking model. In such an embodiment, the illustrated components of the AP MLD 101 represent a single upper MAC (UMAC) layer and other higher layers in the OSI model, which are shared by all subordinate APs 202a-202n.

[0062] For each satellite AP 202a-202n, an RF transceiver 209a-209n receives an incoming RF signal from an antenna 204a-204n, such as a signal transmitted by a STA in the network 100. In some embodiments, each satellite AP 202a-202n operates at a different bandwidth (e.g., 2.4 GHz, 5 GHz, or 6 GHz), and thus the incoming RF signal received by each satellite AP may be at a different RF frequency. The RF transceiver 209a-209n down-converts the input RF signal to generate an IF or baseband signal. The IF or baseband signal is sent to the RX processing circuit 219, which generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuit 219 sends the processed baseband signal to the controller / processor 224 for further processing.

[0063] For each of the attached APs 202a-202n, the TX processing circuitry 214 receives analog or digital data (such as voice data, network data, email, or interactive video game data) from the controller / processor 224. The TX processing circuitry 214 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceivers 209a-209n receive the outgoing processed baseband or IF signals from the TX processing circuitry 214 and up-convert the baseband or IF signals to RF signals that are transmitted via the antennas 204a-204n. In embodiments where each of the attached APs 202a-202n operates at a different bandwidth (e.g., 2.4 GHz, 5 GHz, or 6 GHz), the outgoing RF signals transmitted by each of the attached APs may be at different RF frequencies.

[0064] The controller / processor 224 may include one or more processors or other processing devices that control the overall operation of the AP MLD 101. For example, the controller / processor 224 may control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceivers 209a-209n, the RX processing circuit 219, and the TX processing circuit 214 according to well-known principles. The controller / processor 224 may also support additional functions, such as more advanced wireless communication functions. For example, the controller / processor 224 may support beamforming or directional routing operations, in which the output signals from the multiple antennas 204a-204n are weighted differently to effectively guide the output signals to the desired direction. The controller / processor 224 may also support OFDMA operations, in which outgoing signals are assigned to different subcarrier subsets of different receivers (e.g., different STAs 111-114). The controller / processor 224 may support any of a variety of other functions in the AP MLD 101, including facilitating improved TWT operations between devices in a WLAN. In some embodiments, the controller / processor 224 includes at least one microprocessor or microcontroller. The controller / processor 224 is also capable of executing programs and other processes, such as an OS, that reside in the memory 229. The controller / processor 224 may move data into or out of the memory 229 as required by the executing process.

[0065] The controller / processor 224 is also coupled to a backhaul or network interface 234. The backhaul or network interface 234 allows the AP MLD 101 to communicate with other devices or systems over a backhaul connection or over a network. The interface 234 can support communication over any suitable wired or wireless connection. For example, the interface 234 can allow the AP MLD 101 to communicate over a wired or wireless local area network or over a wired or wireless connection to a larger network (such as the Internet). The interface 234 includes any suitable structure that supports communication over a wired or wireless connection (such as Ethernet or an RF transceiver). The memory 229 is coupled to the controller / processor 224. A portion of the memory 229 may include RAM, and another portion of the memory 229 may include flash memory or other ROM.

[0066] As described in more detail below, AP MLD 101 may include circuitry and / or programming for facilitating improved TWT operations between devices in a WLAN. Figure 2a An example of AP MLD 101 is shown, but the same may be applied to Figure 2a For example, AP MLD 101 may include Figure 2a. As a specific example, the AP MLD 101 may include multiple interfaces 234, and the controller / processor 224 may support routing functions to route data between different network addresses. As another specific example, although each satellite AP 202a-202n is shown as including a single instance of the TX processing circuit 214 and a single instance of the RX processing circuit 219, the AP MLD 101 may include multiple instances of each AP in one or more of the satellite APs 202a-202n (such as one for each RF transceiver). Alternatively, in one or more of the satellite APs 202a-202n, such as in a traditional AP, only one antenna and RF transceiver path may be included. In addition, Figure 2a The various components in may be combined, further subdivided, or omitted, and additional components may be added according to specific needs.

[0067] Figure 2b An example STA 111 is shown according to one embodiment of the present disclosure. Figure 2b The embodiment of STA 111 shown in FIG. is for illustration only, and Figure 1 STAs 111-115 may have the same or similar configurations. In the embodiments discussed below, STA 111 is a non-AP MLD. However, STAs may have a variety of configurations, and Figure 2b The scope of the present disclosure is not limited to any particular implementation of a STA.

[0068] The non-AP MLD 111 is attached to a plurality of STAs 203a-203n (which may be referred to as, for example, STA1-STAn). Each of the attached STAs 203a-203n includes an antenna 205, a radio frequency (RF) transceiver 210, a TX processing circuit 215, and a receive (RX) processing circuit 225. The non-AP MLD 111 also includes a microphone 220, a speaker 230, a controller / processor 240, an input / output (I / O) interface (IF) 245, a touch screen 250, a display 255, and a memory 260. The memory 260 includes an operating system (OS) 261 and one or more applications 262.

[0069] The illustrated components of each dependent STA 203a-203n may represent the PHY layer and LMAC layer in the OSI networking model. In such an embodiment, the illustrated components of the non-AP MLD 111 represent a single UMAC layer and other higher layers in the OSI model, which are shared by all dependent STAs 203a-203n.

[0070] For each affiliated STA 203a-203n, the RF transceiver 210 receives an incoming RF signal sent by the AP of the network 100 from the antenna 205. In some embodiments, each affiliated STA 203a-203n operates at a different bandwidth (e.g., 2.4GHz, 5GHz, or 6GHz), and thus the incoming RF signal received by each affiliated STA can be at a different RF frequency. The RF transceiver 210 down-converts the input RF signal to generate an intermediate frequency (IF) or baseband signal. The IF or baseband signal is sent to the RX processing circuit 225, which generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuit 225 sends the processed baseband signal to the speaker 230 (such as for voice data) or to the controller / processor 240 for further processing (such as for web browsing data).

[0071] For each affiliated STA 203a-203n, the TX processing circuit 215 receives analog or digital voice data from the microphone 220, or receives other outgoing baseband data (such as web data, email, or interactive video game data) from the controller / processor 240. The TX processing circuit 215 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 210 receives the outgoing processed baseband or IF signal from the TX processing circuit 215 and up-converts the baseband or IF signal to an RF signal that is transmitted via the antenna 205. In embodiments where each affiliated STA 203a-203n operates at a different bandwidth (e.g., 2.4 GHz, 5 GHz, or 6 GHz), the outgoing RF signal transmitted by each affiliated STA may be at a different RF frequency.

[0072] The controller / processor 240 may include one or more processors and execute a basic OS program 261 stored in the memory 260 to control the overall operation of the non-AP MLD 111. In one such operation, the main controller / processor 240 controls the reception of forward channel signals and the transmission of reverse channel signals by the RF transceiver 210, the RX processing circuit 225, and the TX processing circuit 215 according to well-known principles. The main controller / processor 240 may also include a processing circuit system configured to facilitate improved TWT operations between devices in the WLAN. In some embodiments, the controller / processor 240 includes at least one microprocessor or microcontroller.

[0073] The controller / processor 240 is also capable of executing other processes and programs resident in the memory 260, such as operations for facilitating improved TWT operations between devices in the WLAN. The controller / processor 240 can move data into or out of the memory 260 as needed for the execution process. In some embodiments, the controller / processor 240 is configured to execute multiple applications 262, such as applications for facilitating improved TWT operations between devices in the WLAN. The controller / processor 240 can operate multiple applications 262 based on the OS program 261 or in response to signals received from the AP. The main controller / processor 240 is also coupled to the I / O interface 245, which provides the non-AP MLD 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 240.

[0074] The controller / processor 240 is also coupled to a touch screen 250 and a display 255. An operator of the non-AP MLD 111 can use the touch screen 250 to input data into the non-AP MLD 111. The display 255 can be a liquid crystal display, a light emitting diode display, or other display capable of presenting text and / or at least limited graphics, such as from a website. A memory 260 is coupled to the controller / processor 240. A portion of the memory 260 can include random access memory (RAM), and another portion of the memory 260 can include flash memory or other read-only memory (ROM).

[0075] although Figure 2b An example of a non-AP MLD 111 is shown, but the Figure 2b Make various changes. For example, Figure 2b The various components in the embodiment may be combined, further subdivided, or omitted, and additional components may be added as required. In a specific example, one or more of the affiliated STAs 203a-203n may include any number of antennas 205 for MIMO communication with the AP 101. In another example, the non-AP MLD 111 may not include voice communications, 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). In addition, although Figure 2b The non-AP MLD 111 is shown configured as a mobile phone or smart phone, but the non-AP MLD may be configured to operate as other types of mobile or fixed devices.

[0076] Figure 3An example of different timing components related to TWT SP according to various embodiments of the present disclosure is shown. In this example, STA1 may be a non-AP STA, such as STA 111. STA1 is a TWT scheduled STA, and AP1 (not shown) is its associated TWT scheduled AP.

[0077] STA1 establishes a broadcast TWT schedule with AP1. t1 is the value of the target wake-up time indicated in the target wake-up time field in the broadcast TWT parameter set field of the TWT element. Therefore, t1 is the time when STA1 should ideally be able to start frame exchange with AP1. Starting from t1, the duration that STA is required to remain awake is the value of the nominal wake-up time (T) indicated in the nominal minimum TWT wake-up duration field in the broadcast TWT parameter set field. Due to various reasons, STA1 may not be able to start frame exchange with AP1 at the nominal SP start time t1. The actual SP start time may be much later. In the figure, the actual SP start time is represented as time t2. Using the delayed actual SP start time, the minimum wake-up duration of STA1 is also adjusted and is indicated as adjusted minimum wake-up duration = T-(t2-t1).

[0078] The TWT information frame is sent by a STA to request or deliver information about TWT, and is transmitted by a STA having a TWT agreement or TWT schedule, or by a STA to its peer STA. The format of the TWT information frame is shown in Table 1.

[0079] Table 1

[0080]

[0081]

[0082] Figure 4 An example format of the TWT information field 402 in the TWT information frame of Table 1 according to an embodiment of the present disclosure is shown.

[0083] According to one embodiment, using a variation of the TWT information frame, a specific broadcast TWT schedule for STAs that are members of the corresponding schedule may be paused or resumed.

[0084] Figure 5 An example of a broadcast TWT schedule suspension for a specific broadcast TWT schedule according to an embodiment of the present disclosure is shown. In this example, the AP may be AP 101, and STA1 may be a non-AP STA, such as STA 111. Figure 5 In the example, TWT information frame 502 is used by STA1 to suspend the broadcast TWT schedule until time t7.

[0085] According to one embodiment, using a variation of the TWT information frame, a specific broadcast TWT schedule for STAs that are members of the corresponding schedule may be suspended or resumed while maintaining any other TWT agreements or schedules for the STAs (which may be uninterrupted members).

[0086] Figure 6 An example of pausing a broadcast TWT schedule for a specific broadcast TWT schedule while maintaining other broadcast TWT schedules according to an embodiment of the present disclosure is shown. In this example, the AP may be AP 101, and STA1 may be a non-AP STA, such as STA 111. Figure 6 In the example of , STA1 uses the TWT information frame 602 to suspend the broadcast TWT schedule indicated as schedule-1 until time t13. At the same time, the broadcast TWT schedule indicated as schedule-2 is maintained.

[0087] According to one embodiment, in order to indicate that the TWT information frame is intended for a specific broadcast TWT schedule, an identifier for specifying the corresponding broadcast TWT schedule may be included in the TWT information field. According to one embodiment, a broadcast TWT ID subfield may be included in the TWT information field. This modified (relative to the existing specification) TWT information field may be referred to as an EHT variant TWT information field.

[0088] Figure 7 An example format of an EHT variant TWT information field 702 including a broadcast TWT ID subfield 704 according to an embodiment of the present disclosure is shown. The interpretation and use of the TWT stream identifier subfield, the response request subfield, the next TWT request subfield, the next TWT subfield size subfield, all TWT subfields, and the next TWT subfield in the EHT variant TWT information field 702 are similar to those of the TWT information field (e.g., Figure 4 The broadcast TWT ID subfield 704 in the EHT variant TWT information field 702 may be the same value as the value of the broadcast TWT ID subfield in the broadcast TWT information subfield in the broadcast TWT parameter set field corresponding to the broadcast TWT schedule intended to be paused or resumed by the TWT information field.

[0089] A STA in a BSS may be a member of one or more broadcast TWT schedules and a member of one or more individual TWT agreements. In order to distinguish whether the EHT variant TWT information field is intended for a specific broadcast TWT schedule or a separate TWT agreement, an indicator subfield may be introduced in the EHT variant TWT information field. For example, if the indicator subfield is set to 0, it may indicate that the corresponding EHT variant TWT information field is intended for the individual TWT agreement to which the STA subscribes. Otherwise, it may indicate that the corresponding EHT variant TWT information field is intended for a broadcast TWT schedule of which the STA is a member, or vice versa.

[0090] According to one embodiment, a negotiation type subfield may be included in the EHT variant TWT information field to specify whether the TWT information frame is intended for an individual TWT agreement, a broadcast TWT schedule, or both.

[0091] Figure 8 An example format of the EHT variant TWT information field 802 including the negotiation type subfield 804 according to an embodiment of the present disclosure is shown. Table 2 shows the encoding of the negotiation type subfield 804 value in the EHT variant TWT information field 802.

[0092] Table 2

[0093]

[0094]

[0095] According to one embodiment, the value 2 in Table 2 may be used in conjunction with all TWT subfields of the EHT variant TWT information field 802. For example, if all TWT subfields in the EHT variant TWT information field 802 are set to 1, the negotiation type subfield 804 in the EHT variant TWT information field 802 may be set to 2 to indicate that all TWTs (both individual TWT agreements and broadcast TWT schedules) are intended to be intended by the EHT variant TWT information field (i.e., intended to be suspended or resumed).

[0096] According to one embodiment, if the Negotiation Type subfield in the EHT Variant TWT Information field is set to 0, the Broadcast TWT ID subfield in the EHT Variant TWT Information field is reserved.

[0097] According to one embodiment, if the Negotiation Type subfield in the EHT Variant TWT Information field is set to 1, the TWT Stream Identifier subfield in the EHT Variant TWT Information field is reserved.

[0098] According to one embodiment, if all TWT subfields are set to 1, it indicates that all individual TWT agreements subscribed by the STA are intended by the EHT variant TWT information field. According to one embodiment, it may indicate that all broadcast TWT schedules of which the STA is a member are intended by the EHT variant TWT information field. According to another embodiment, it may indicate that both individual TWT agreements and broadcast TWT schedules are intended by the EHT variant TWT information field.

[0099] According to one embodiment, if all TWT subfields in the EHT variant TWT information field are set to 1, the TWT stream identifier subfield and the broadcast TWT ID subfield may be reserved. According to one embodiment, if all TWT subfields are set to 1, the negotiation type subfield may be reserved.

[0100] According to one embodiment, if all TWT subfields in the EHT variant TWT information field are set to 1 and the negotiation type subfield is set to 0, it may indicate that all individual TWT agreements subscribed by the STA are intended by the EHT variant TWT information field. In such a case, according to one embodiment, the TWT stream identifier subfield may be reserved and the broadcast TWT ID subfield may also be reserved. According to one embodiment, if all TWT subfields in the EHT variant TWT information field are set to 1 and the negotiation type subfield is set to 1, it may indicate that all broadcast TWT schedules of which the STA is a member are intended by the EHT variant TWT information field. In such a case, according to one embodiment, the broadcast TWT ID subfield in the EHT variant TWT information field may be reserved and the TWT stream identifier subfield may also be reserved.

[0101] According to one embodiment, if all TWT subfields in the EHT variant TWT information field are set to 0, the EHT variant TWT information field may be intended for a specific broadcast TWT schedule indicated by the broadcast TWT ID subfield or a specific individual TWT agreement indicated by the TWT stream identifier subfield, as specified by the negotiation type subfield.

[0102] Possible interpretations and usages of all TWT subfields in conjunction with the Negotiation Type subfield in the EHT variant TWT Information field are shown in Table 3. Other interpretations and usages are also possible.

[0103] Table 3

[0104]

[0105]

[0106] According to one embodiment, a frame carrying an EHT variant TWT information field may be referred to as an EHT variant TWT information frame. Table 4 shows a possible EHT variant TWT information frame format.

[0107] Table 4

[0108] order information 1 category 2 Unprotected S1G action 3 EHT variant TWT information field

[0109] According to one embodiment, the unprotected S1G action field value may contain a value for the EHT variant TWT information field. For example, according to one embodiment, a value of 10 may be used, or any currently reserved value from values ​​12-255 may be used, as shown in Table 4A.

[0110] Table 4A

[0111]

[0112]

[0113] According to one embodiment, both the TWT information field and the EHT variant TWT information field may be included in the EHT variant TWT information frame, as shown in Table 5.

[0114] Table 5

[0115] order information 1 category 2 Unprotected S1G action 3 TWT Information Fields 4 EHT variant TWT information field

[0116] According to one embodiment, the TWT information frame may be specific to the broadcast TWT. Such a TWT information frame may be referred to as a broadcast TWT information frame. The broadcast TWT information frame may include a broadcast TWT information field.

[0117] Fig. 9 An example format of the broadcast TWT information field 902 according to an embodiment of the present disclosure is shown.

[0118] According to one embodiment, the broadcast TWT information frame is intended for a broadcast TWT schedule subscribed by a STA and identified by a broadcast TWT ID subfield of the broadcast TWT information field 902. According to one embodiment, if all TWT subfields of the broadcast TWT information field 902 are set to 1, the broadcast TWT information frame is intended for all broadcast TWT schedules subscribed by the STA, in which case the broadcast TWT ID subfield may be retained.

[0119] According to one embodiment, the TWT information frame may be specific to a restricted TWT. Such a TWT information frame may be referred to as a restricted TWT information frame. The restricted TWT information frame may include a restricted TWT information field. The format of the restricted TWT information field may be the same as the format of the broadcast TWT information field 902. According to one embodiment, the restricted TWT information frame is intended for one or more restricted TWT schedules and may not be applicable to other broadcast TWT schedules that are not restricted TWT schedules, or to other individual TWT agreements.

[0120] Restricted TWT operation supports delay-sensitive applications of STAs. STAs may need to prioritize their delay-sensitive applications over their power saving needs. When pausing or resuming all TWT SPs by setting all TWT subfields of the TWT information frame, an r-TWT scheduled STA may want to exclude its restricted TWT scheduling from suspension (or resumption). In order to achieve such operation, a restricted TWT exclusion subfield may be included in the EHT variant TWT information field as an indicator for excluding or including restricted TWT scheduling.

[0121] Fig.10 An example format of the EHT variant TWT information field 1002 including the restricted TWT exclusion subfield 1004 according to an embodiment of the present disclosure is shown. If all TWT subfields are set to 1 and the restricted TWT exclusion subfield 1004 is set to 1, it may indicate that the EHT variant TWT information field 1002 is intended for all broadcast TWT schedules or individual TWT agreements (e.g., for suspending or resuming a TWT SP) except for the restricted TWT schedule of which the STA is a member.

[0122] According to one embodiment, reference Fig.10 and Table 3, if all TWT subfields are set to 0, the restricted TWT exclusion subfield 1004 may be retained.

[0123] According to one embodiment, reference Fig.10 and Table 3, if all TWT subfields are set to 1 and the negotiation type subfield is set to 0, the restricted TWT exclusion subfield 1004 may be retained.

[0124] According to one embodiment, reference Fig.10 and Table 3, if all TWT subfields are set to 1 and the negotiation type subfield is set to 3, the restricted TWT exclusion subfield 1004 can be retained.

[0125] According to one embodiment, reference Fig.10and Table 3, if all TWT subfields are set to 1 and the negotiation type subfield is set to 1, and if the restricted TWT exclusion subfield 1004 is set to 1, it may indicate that the EHT variant TWT information field is intended for all broadcast TWT schedules (e.g., for pause or resume) of which the STA is a member, except for the restricted TWT schedule of which the STA is a member. According to one embodiment, if all TWT subfields are set to 1 and the negotiation type subfield is set to 1, and if the restricted TWT exclusion subfield 1004 is set to 0, it may indicate that the EHT variant TWT information field is intended for all broadcast TWT schedules (e.g., for pause or resume) of which the STA is a member, including the restricted TWT schedule of which the STA is a member.

[0126] According to one embodiment, referring to Fig.10 and Table 3, if all TWT subfields are set to 1 and the negotiation type subfield is set to 2, and if the restricted TWT exclusion subfield 1004 is set to 1, it may indicate that the EHT variant TWT information field is intended to be used for (e.g., for suspending or resuming) all individual TWT agreements and broadcast TWT schedules of which the STA is a member, except for the restricted TWT schedule of which the STA is a member. According to one embodiment, if all TWT subfields are set to 1 and the negotiation type subfield is set to 2, and if the restricted TWT exclusion subfield 1004 is set to 0, it may indicate that the EHT variant TWT information field is intended to be used for (e.g., for suspending or resuming) all individual TWT agreements and broadcast TWT schedules of which the STA is a member, including the restricted TWT schedule of which the STA is a member.

[0127] According to one embodiment, if all TWT subfields are set to 1, the restricted TWT exclusion subfield 1004 may be retained.

[0128] Fig.11 An example format of an EHT variant TWT information field 1102 including an all restricted TWT subfield 1104 according to an embodiment of the present disclosure is shown. If all restricted TWT subfields 1104 are set to 1, it indicates that the TWT information frame is intended for (e.g., for pausing and resuming) all restricted TWT schedules of which the STA of the R-TWT schedule receiving or transmitting the EHT variant TWT information field 1102 is a member. According to one embodiment, if all restricted TWT subfields 1104 are set to 1, the restricted TWT exclusion subfield may be retained. According to one embodiment, if the restricted TWT exclusion subfield is set to 1, all restricted TWT subfields 1104 may be retained. According to one embodiment, if all restricted TWT subfields 1104 are set to 1, the TWT stream identifier subfield and the broadcast TWT ID subfield may be retained.

[0129] Fig.12 FIG. 10 shows an example format of the EHT variant TWT information field 1202 including all restricted TWT subfields 1104 when the negotiation type subfield is set to 0 and all TWT subfields are set to 0 according to an embodiment of the present disclosure. Fig.11 , if the negotiation type subfield is set to 0 and all TWT subfields are set to 0, the format of the EHT variant TWT information field 1202 may be used.

[0130] Fig.13 An example format of the EHT variant TWT information field 1302 including all restricted TWT subfields 1104 when the negotiation type subfield is set to 0 and all TWT subfields are set to 0 according to an embodiment of the present disclosure is shown. Fig.11 , if the negotiation type subfield is set to 0 and all TWT subfields are set to 0, the format of the EHT variant TWT information field 1302 may be used.

[0131] Fig.14 An example format of the EHT variant TWT information field 1402 including all restricted TWT subfields 1104 according to an embodiment of the present disclosure is shown. Fig.11 , the EHT variant TWT information field 1402 may be used when any of the following occurs: all TWT subfields are set to 1, the negotiation type subfield is set to 2 or 3, or all restricted TWT subfields are set to 1.

[0132] According to one embodiment, restricted TWT scheduling can be selectively excluded. To achieve this, another format of the EHT variant TWT information field can be used.

[0133] Fig.15 An example format of an EHT variant TWT information field 1502 according to an embodiment of the present disclosure is shown, which enables the use of the rTWT schedule exclusion information subfield 1504 to selectively exclude restricted TWT schedules. According to one embodiment, the number of excluded rTWT schedules subfield 1506 indicates the number of rTWT schedules excluded from the list of TWT schedules or agreements intended by the EHT variant TWT information field 1502.

[0134] exist Fig.15In the example, "N" may be the number of excluded r-TWT schedules. The value may be the value set in the number of excluded rTWT schedules subfield 1506. For example, if the number of excluded rTWT schedules subfield is set to 2, there may be two broadcast TWT ID subfields 1508 in the rTWT schedule exclusion information subfield 1504 following the number of excluded rTWT schedules subfield 1506: the first broadcast TWT ID corresponds to the first restricted TWT schedule that is excluded (e.g., schedule-1), and the second broadcast TWT ID corresponds to the second restricted TWT schedule that is excluded (e.g., schedule-2). Accordingly, the number of reserved bits in the rTWT schedule exclusion information subfield 1504 may be 3 (i.e., the number of bits required to make the total number of bits in the rTWT schedule exclusion information subfield an integer multiple of 8).

[0135] According to one embodiment, if the restricted TWT exclusion subfield in the EHT variant TWT information field 1502 is set to 0, the rTWT scheduling exclusion information subfield 1504 may be retained.

[0136] According to one embodiment, reference Fig.15 , the length subfield may be included in the rTWT scheduling exclusion information subfield in the EHT variant TWT information field to indicate the length of the rTWT scheduling exclusion information subfield. The length may be represented in octets.

[0137] According to one embodiment, reference Fig.15 , all R-TWT subfields may be included in the rTWT scheduling exclusion information subfield in the EHT variant TWT information field. All R-TWT subfields may indicate that all restricted TWT scheduling of which the STA is a member is intended by the EHT variant TWT information field.

[0138] According to one embodiment, the same information frame can be used to suspend or resume multiple TWT schedules or agreements. To achieve this, a generalized TWT information frame can be used. The format of the generalized TWT information frame is shown in Table 6.

[0139] Table 6

[0140] order information 1 category 2 Unprotected S1G action 3 Generalized TWT information field

[0141] Fig.16 An example format of the generalized TWT information field 1602 of the generalized TWT information frame of Table 6 according to an embodiment of the present disclosure is shown. Fig.16, the TWT schedule / agreement number subfield 1604 indicates the number of broadcast TWT schedules or individual TWT agreements whose information is provided by the generalized TWT information frame 1602. The TWT information set subfield 1606 contains one or more TWT information set subfields as specified by the value set in the TWT schedule / agreement number subfield 1604.

[0142] Fig.17 An example format of a TWT information set subfield 1702 according to an embodiment of the present disclosure is shown. One or more TWT information set subfields 1702 may be included in Fig.16 In the TWT information set subfield 1606.

[0143] exist Fig.17 The Negotiation Type subfield indicates whether the TWT information set is for an individual TWT agreement as identified by the TWT Stream Identifier subfield in the TWT Information Set subfield, or for a broadcast TWT schedule as identified by the Broadcast TWT ID subfield in the TWT Information Set subfield.

[0144] According to one embodiment, the frame for providing TWT information may be specific to the restricted TWT. For this purpose, a generalized restricted TWT information frame may be used. The format of the generalized restricted TWT information frame is shown in Table 7.

[0145] Table 7

[0146] order information 1 category 2 Unprotected S1G action 3 Generalized restricted TWT information field

[0147] Fig.18 An example format of the generalized restricted TWT information field 1802 of the generalized restricted TWT information frame of Table 7 according to an embodiment of the present disclosure is shown.

[0148] According to one embodiment, if the r-TWT scheduling of an r-TWT scheduled STA is suspended (for example, by using an EHT variant TWT information frame, or a generalized TWT information frame, or a generalized restricted TWT information frame), the STA may behave as if the STA is not a member of the corresponding restricted TWT scheduling during the suspended restricted TWT SP until the r-TWT scheduling is resumed. For example, according to this embodiment, the STA may terminate any transmission opportunity (TXOP) it may have obtained before the start of the restricted TWT SP suspended for the STA. As another example, according to this embodiment, the STA may observe any silent interval announced by the r-TWT scheduling AP to protect the corresponding restricted TWT SP suspended for the STA. According to one embodiment, even during the suspended r-TWT SP for the STA, the STA may not end its TXOP before the r-TWT SP start time, and may not follow the silent interval announced by the r-TWT scheduling AP to protect the corresponding r-TWT SP.

[0149] According to one embodiment, if the r-TWT scheduling is suspended for an STA scheduled for r-TWT, and if there are no other STAs that are members of the r-TWT scheduling, STAs that are not STAs of the r-TWT scheduling corresponding to the suspended scheduling may not need to end their TXOPs before the suspended r-TWT SP starts. According to one embodiment, STAs that are not STAs of the r-TWT scheduling corresponding to the suspended scheduling may ignore the silent interval corresponding to the protection of the suspended R-TWT SP.

[0150] According to one embodiment, if multiple STAs are members of r-TWT scheduling, and the r-TWT scheduling is suspended for the member STAs at least until time t1, the r-TWT scheduling AP may send a notification message in a message in its BSS, which indicates that the r-TWT scheduling is suspended in the BSS until time t1. The notification message may be broadcast in nature, or may be incorporated into a beacon frame or a probe response frame or a (re) association response frame. The notification message may include the following information:

[0151] -Identifier of the suspended restricted TWT schedule. For example, the identifier may be the broadcast TWT ID corresponding to the restricted TWT schedule.

[0152] - At least one STA that is a member of the schedule will resume the minimum time of its r-TWT schedule. For example, there may be three member STAs for the r-TWT schedule. The schedules for the three STAs are respectively suspended until times t1, t2, and t3, where t1 < t2 < t3. In the notification message, the AP may include the value of t1. This value may be the next target wake-up time (next TWT) value of the schedule.

[0153] - The size of the next TWT value.

[0154] - An indication of whether a response has been requested from the recipient of the message.

[0155] According to one embodiment, the AP may use a restricted TWT pause information frame to convey the above information. A possible format of the restricted TWT pause information frame is shown in Table 8.

[0156] Table 8

[0157] order information 1 category 2 Unprotected S1G action 3 Restricted TWT Pause Information Field

[0158] Fig.19 Shows an example format of the restricted TWT pause information field 1902 of the restricted TWT pause information frame of Table 8 according to an embodiment of the present disclosure.

[0159] The broadcast TWT ID subfield in the restricted TWT pause information field 1902 specifies the broadcast TWT ID corresponding to the restricted TWT schedule that is suspended and whose information is carried in the restricted TWT pause information frame.

[0160] The response request subfield in the restricted TWT pause information field 1902 indicates whether the sender of the restricted TWT pause information frame requests a response frame when the receiver receives the frame.

[0161] The next TWT subfield size subfield in the restricted TWT pause information field 1902 indicates the size of the next TWT subfield of the restricted TWT pause information field. The encoding of the next TWT subfield size subfield 1902 is shown in Table 9.

[0162] Table 9

[0163]

[0164] The next TWT subfield in the restricted TWT pause information field 1902 has a variable size, which is determined by the value set in the next TWT subfield size subfield based on the encoding described in Table 9. The next TWT subfield contains the value of the least significant part of the TSF of the next TWT value of the corresponding restricted TWT schedule whose information is carried in the restricted TWT pause information frame.

[0165] Fig. 20 Flowchart example 2002 is shown illustrating example behavior of an AP in the context of using a restricted TWT pause information frame according to an embodiment of the present disclosure.

[0166] Fig.21 A flowchart example 2102 is shown of example behavior of a non-AP STA in the context of using a restricted TWT-PAUSE information frame according to an embodiment of the present disclosure.

[0167] According to one embodiment, the generalized restricted TWT pause information frame may carry r-TWT pause information for multiple r-TWT schedules. An example format of the generalized restricted TWT pause information frame is shown in Table 10.

[0168] Table 10

[0169] order information 1 category 2 Unprotected S1G action 3 Generalized Restricted TWT Pause Information Field

[0170] Fig. 22 An example format of the generalized restricted TWT pause information field 2202 of the generalized restricted TWT pause information frame of Table 10 according to an embodiment of the present disclosure is shown.

[0171] According to one embodiment, the information contained in the restricted TWT pause information frame and the generalized restricted TWT pause information frame may also be carried in an element format, for example, by using a restricted TWT pause information element and a generalized restricted TWT pause information element, respectively. The formats of the restricted TWT pause information element and the generalized restricted TWT pause information element may be similar to the formats of the restricted TWT pause information field and the generalized restricted TWT pause information field, respectively. The restricted TWT pause information element and the generalized restricted TWT pause information element may be carried in a beacon frame, a probe response frame, a (re)association response frame or other management or data frames.

[0172] According to one embodiment, the AP may use a restricted TWT pause information frame or a generalized restricted TWT pause information frame to notify the STAs in its BSS that the AP is unavailable until the time indicated in the next TWT subfield in the corresponding frame. According to this embodiment, a STA that receives a restricted TWT pause information frame or a generalized restricted TWT pause information frame from an AP may not be able to perform frame exchange with the AP until the time indicated in the next TWT subfield, regardless of whether the STA supports TWT operation. An AP attached to an AP MLD may use this mechanism to temporarily disable a link (e.g., for power saving purposes).

[0173] According to one embodiment, a STA affiliated to a non-AP MLD or an AP affiliated to an AP MLD operating on a link may suspend or resume a TWT agreement or TWT schedule established on another link between the same AP MLD and the non-AP MLD.

[0174] According to one embodiment, when a non-AP MLD is associated with an AP MLD, a STA attached to the non-AP MLD and operating on a link between the AP MLD and the non-AP MLD, or an AP attached to the AP MLD and operating on a link between the AP MLD and the non-AP MLD, may send an MLO supported TWT information frame on the link to suspend or resume a TWT agreement or TWT schedule established on another link between the same AP MLD and the non-AP MLD. The format and usage of the MLO supported TWT information frame may be similar to the format and usage of the EHT variant TWT information frame with additional link-specific TWT information disclosed above. For example, a link ID may be included in the MLO supported TWT information frame to indicate which link among multiple links between the AP MLD and the non-AP MLD the TWT information carried in the MLO supported TWT information frame is intended for.

[0175] According to one embodiment, instead of link ID information, a link ID bitmap may also be used. Table 11 shows a possible format of a TWT information frame supporting MLO.

[0176] Table 11

[0177] order information 1 category 2 Unprotected S1G action 3 TWT information frame supporting MLO

[0178] Fig.23 An example format of the MLO-supported TWT information field 2302 of the MLO-supported TWT information frame of Table 11 according to an embodiment of the present disclosure is shown.

[0179] exist Fig.23 In the TWT information, the link ID bitmap subfield 2304 specifies the MLO link for which TWT information (e.g., for pausing or resuming the TWT SP for the corresponding TWT scheduling or TWT agreement) is provided in the TWT information field 2302 supporting MLO. If the bit in the bitmap is set to 1, it may indicate that the TWT information of the corresponding link is provided in the TWT information field supporting MLO carrying the bitmap. Otherwise, the TWT information of the corresponding link is not provided in the TWT information field supporting MLO.

[0180] exist Fig.23 , the TWT information subfield 2306 for the link set contains one or more per-link TWT information subfields 2308 , depending on the total number of 1s in the link ID bitmap of the TWT information subfield 2304 .

[0181] exist Fig.23 In the example, the example TWT information set subfield 2310 has Fig.15The same format as the EHT variant TWT information field 1502. However, it should be understood that the TWT information set subfield 2310 may use another format, such as the format of any of the EHT variant TWT information fields disclosed above.

[0182] Fig.24 An example process for facilitating TWT operations between MLDs using a TWT information frame supporting MLO according to one embodiment of the present disclosure is shown. Fig.24 The process is discussed as being performed by a non-AP MLD, but it should be understood that the corresponding AP MLD performs the corresponding process. Fig.24 The processes are discussed as being performed by a WI-FI non-AP MLD including a plurality of STAs, each STA including a transceiver configured to form a link with a corresponding AP attached to a WI-FI AP MLD. However, it should be understood that any suitable wireless communication device may perform these processes.

[0183] refer to Fig.24 The process begins with the non-AP MLD sending or receiving a TWT information frame supporting MLO to or from the AP MLD through the first link in the links formed between the STA and the AP attached to the AP MLD, the TWT information frame supporting MLO including an indication of suspending or resuming the TWT SP on the second link in the links (step 2405).

[0184] In some embodiments, the indication is an indication to suspend or resume an individual TWT agreement established on the second link, and the TWT SP corresponds to the individual TWT agreement. In other embodiments, the indication is an indication to suspend or resume a broadcast TWT schedule established on the second link, and the TWT SP corresponds to the broadcast TWT schedule.

[0185] In some embodiments, the TWT information frame (possibly in conjunction with another frame) includes the TWT information and a link ID of the second link, the link ID indicating that the TWT information is intended for the second link and that the TWT information indicates pausing or resuming the TWT SP.

[0186] In other embodiments, the TWT information frame (possibly in conjunction with another frame) includes TWT information sets intended for one or more links, respectively, and a link ID bitmap indicating the one or more links including a second link, and each TWT information set indicates that the TWT SP on the corresponding link is to be suspended or resumed. In some such embodiments, each TWT information set includes at least one broadcast TWT ID or TWT stream ID. The broadcast TWT ID identifies a broadcast TWT schedule established on the corresponding link, and the TWT stream ID identifies an individual TWT agreement established on the corresponding link. In some such embodiments, the TWT SP is not suspended or resumed on a link not indicated in the link ID bitmap.

[0187] Next, based on the successful transmission or reception of the TWT information frame on the first link in step 2405, the non-AP MLD suspends or resumes the TWT SP on the second link (step 2410).

[0188] The above flow charts illustrate example methods or processes that can be implemented according to the principles of the present disclosure, and various changes can be made to the methods or processes shown in the flow charts. For example, although shown as a series of steps, various steps can overlap, occur in parallel, occur in different orders, or occur multiple times. In another example, a step can be omitted or replaced by another step.

[0189] According to one embodiment, the value set as the scheduling recovery time in the next TWT subfield in any proposed frame in the present disclosure may be extracted from a TWT set for broadcast or restricted TWT scheduling negotiated between the TWT scheduling AP and the TWT scheduled STA. According to one embodiment, the value set in the next TWT subfield may not necessarily be extracted from the TWT set negotiated between the TWT scheduling AP and the TWT scheduled STA, that is, the next TWT subfield in the proposed frame may be any positive value (i.e., flexible TWT).

[0190] According to one embodiment, the EHT variant TWT information frame or the generalized TWT information frame may also be a protected information frame. In this case, the second field of the corresponding frame may be a protected action field.

[0191] Although the present disclosure has been described with exemplary embodiments, various changes and modifications may be suggested to those skilled in the art. The present disclosure is intended to cover these changes and modifications that fall within the scope of the appended claims. The description in this application should not be interpreted as implying that any particular element, step or function is an essential element that must be included in the scope of the claims. The scope of the patent subject matter is defined by the claims.

Claims

1. A non-access point AP multi-link device MLD, comprising: A station (STA) including a transceiver, the transceiver being configured to form a link with an AP, respectively, the AP being affiliated with an APMLD; as well as a processor operatively coupled to the transceiver, wherein a first transceiver among the transceivers is further configured to send or receive a target wake-up time (TWT) information frame supporting multi-link operation (MLO) to or from the AP MLD on a first link among the links, the TWT information frame including an indication of suspending or resuming a TWT service period (SP) on a second link among the links, and The processor is configured to suspend or resume the TWT SP on the second link based on the TWT information frame being successfully sent or received on the first link.

2. The non-AP MLD according to claim 1, wherein: The indication is an indication to suspend or resume an individual TWT agreement established on the second link, and TWT SP corresponds to an individual TWT agreement.

3. The non-AP MLD according to claim 1 or claim 2, wherein: The indication is an indication to suspend or resume the broadcast TWT schedule established on the second link, and TWT SP corresponds to the broadcast TWT schedule.

4. A non-AP MLD according to any one of the preceding claims, wherein: The TWT information frame includes, in combination with another frame, TWT information and a link identifier (ID) of the second link, the link identifier (ID) indicating that the TWT information is intended for the second link, and The TWT information indicates pausing or resuming the TWT SP.

5. A non-AP MLD according to any one of the preceding claims, wherein: The TWT information frame includes, in combination with another frame, TWT information sets intended for one or more links respectively and a link ID bitmap indicating the one or more links including the second link, and Each TWT information set indicates pausing or resuming the TWT SP on the corresponding link.

6. A non-AP MLD according to any one of the preceding claims, wherein: Each TWT information set includes at least one broadcast TWT ID or TWT stream ID, The broadcast TWT ID identifies the broadcast TWT schedule established on the corresponding link, and The TWT flow ID identifies the individual TWT protocol established on the corresponding link.

7. A non-AP MLD according to any one of the preceding claims, wherein: On links not indicated in the link ID bitmap, the TWT SP is not suspended or resumed.

8. An access point AP multi-link device MLD, comprising: The AP includes a transceiver configured to form a link with a station (STA), respectively, the STA being affiliated with the non-AP MLD; as well as a processor operatively coupled to the transceiver, wherein a first transceiver among the transceivers is further configured to send or receive a target wake-up time (TWT) information frame supporting multi-link operation (MLO) to or from the non-AP MLD on a first link among the links, the TWT information frame including an indication of suspending or resuming a TWT service period (SP) on a second link among the links, and The processor is configured to suspend or resume the TWT SP on the second link based on the TWT information frame being successfully sent or received on the first link.

9. The AP MLD according to claim 8, wherein: The indication is an indication to suspend or resume an individual TWT agreement established on the second link, and TWT SP corresponds to an individual TWT agreement.

10. The AP MLD according to claim 8 or 9, wherein: The indication is an indication to suspend or resume the broadcast TWT schedule established on the second link, and TWT SP corresponds to the broadcast TWT schedule.

11. The AP MLD according to any one of claims 8 to 10, wherein: The TWT information frame includes, in combination with another frame, TWT information and a link identifier (ID) of the second link, the link identifier (ID) indicating that the TWT information is intended for the second link, and The TWT information indicates pausing or resuming the TWT SP.

12. The AP MLD according to any one of claims 8 to 11, wherein: The TWT information frame includes, in combination with another frame, TWT information sets intended for one or more links respectively and a link ID bitmap indicating the one or more links including the second link, and Each TWT information set indicates pausing or resuming the TWT SP on the corresponding link.

13. The AP MLD according to any one of claims 8 to 12, wherein: Each TWT information set includes at least one broadcast TWT ID or TWT stream ID, The broadcast TWT ID identifies the broadcast TWT schedule established on the corresponding link, and The TWT flow ID identifies the individual TWT protocol established on the corresponding link.

14. The AP MLD according to any one of claims 8 to 13, wherein: The TWT SP is not suspended or resumed on links not indicated in the link ID bitmap.

15. A method of wireless communication performed by a non-access point (AP) multi-link device (MLD) including a station (STA), the method comprising: Sending or receiving a target wake-up time (TWT) information frame supporting multi-link operation (MLO) to or from the AP MLD on a first link among links formed between the STA and an AP affiliated to the AP MLD, the TWT information frame including an indication of suspending or resuming a TWT service period (SP) on a second link among the links; and Based on the TWT information frame being successfully sent or received on the first link, suspend or resume the TWT SP on the second link.

Images