Cooperative Scheduling and Signaling for Restricted Target Wake Time (R-TWT) Service Periods

Abstract

The present disclosure provides methods, devices, and systems for protecting latency-sensitive communications during a restricted target wake time (r-TWT) service period (SP). Some implementations relate more specifically to coordinated scheduling of r-TWT SPs between BSSs. In some aspects, a first AP may coordinate with a second AP in scheduling r-TWT SPs such that latency-sensitive traffic in the first BSS does not interfere or collide with latency-sensitive traffic in a second BSS that overlaps with the first BSS. In some implementations, the first and second APs may schedule their respective r-TWT SPs to be orthogonal in time. In some other implementations, the first and second APs may schedule their r-TWT SPs to overlap in time when allocating coordinated resources to simultaneous or overlapping latency-sensitive traffic in the first and second BSSs (e.g., according to one or more multi-AP cooperation techniques).

Description

[Technical field]

[0001] cross reference

[0001] This patent application claims the benefit of U.S. patent application Ser. No. 17 / 516,375, entitled "COORDINATED SCHEDULING AND SIGNALING OF RESTRICTED TARGET WAKE TIME (R-TWT) SERVICE PERIODS," by AJAMI et al., filed on November 1, 2021, which is assigned to the assignee of this application and expressly incorporated by reference into this specification.

[0002] FIELD OF THE DISCLOSURE

[0002] The present disclosure relates generally to wireless communications, and more specifically, to coordinated scheduling and signaling for restricted Target Wake Time (r-TWT) service periods.

[0003] 2. Description of Related Art

[0003] A wireless local area network (WLAN) may be formed by one or more access points (APs) that provide a shared wireless communication medium for use by several client devices, also called stations (STAs). The basic building block of a WLAN conforming to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 family is the Basic Service Set (BSS) managed by the AP. Each BSS is identified by a Basic Service Set Identifier (BSSID) advertised by the AP. The AP periodically broadcasts a beacon frame to enable any STA within wireless range of the AP to establish or maintain a communication link with the WLAN.

[0004]

[0004] Some wireless communication devices may be associated with low-latency applications that have strict end-to-end latency, throughput, and timing requirements for data traffic. Exemplary low-latency applications include, but are not limited to, real-time gaming applications, video communications, and augmented reality (AR) and virtual reality (VR) applications (collectively referred to as extended reality (XR) applications). Such low-latency applications may specify various latency, throughput, and timing requirements for wireless communication systems that provide connectivity to these applications. It is therefore desirable to ensure that a WLAN can meet the various latency, throughput, and timing requirements of such low-latency applications. Summary of the Invention

[0005]

[0005] The systems, methods, and devices of the present disclosure each have several innovative aspects, no single aspect of which is solely responsible for the desirable properties disclosed herein.

[0006]

[0006] One innovative aspect of the subject matter described in this disclosure may be realized as a method of wireless communication. The method may be performed by a wireless communication device and includes receiving coordinated restricted target wake time (r-TWT) signaling information associated with a first r-TWT service period (SP) associated with an overlapping basic service set (OBSS), transmitting r-TWT schedule information indicating a second r-TWT SP associated with a basic service set (BSS) associated with the wireless communication device based on the coordinated r-TWT signaling information, and communicating with one or more first wireless stations (STAs) during the second r-TWT SP based on a respective latency requirement of each of the one or more first STAs.

[0007] In some aspects, the first r-TWT SP may be orthogonal in time with the second r-TWT SP. In some other aspects, the first r-TWT may overlap in time with the second r-TWT SP. In some implementations, communicating with the one or more first STAs may include transmitting a multi-user request-to-send (MU-RTS) frame to the one or more first STAs. In some other implementations, the coordinated r-TWT signaling information may include shared SP information indicating a multiple access point (multi-AP) coordination opportunity associated with the first r-TWT SP. In such implementations, communicating with the one or more first STAs may include coordinating with an access point (AP) associated with the OBSS based on the shared SP information such that communication with the one or more first STAs occurs simultaneously with communication in the OBSS.

[0008] In some implementations, coordinating with the AP may include exchanging transmit power information with the AP indicating at least one of a transmit power associated with communication with the one or more first STAs or a transmit power associated with communication in the OBSS. In some other implementations, coordinating with the AP may include exchanging frequency resource information with the AP indicating at least one of an allocation of frequency resources for communication with the one or more first STAs or an allocation of frequency resources for communication in the OBSS.

[0009] In some aspects, the cooperative r-TWT signaling information may indicate an allocation of resources for the second r-TWT SP. In some other aspects, the cooperative r-TWT signaling information may indicate an allocation of resources for the first r-TWT SP. In some implementations, the method may further include negotiating an allocation of resources for the second r-TWT SP with an AP associated with the OBSS based on the cooperative r-TWT signaling information. In some implementations, the cooperative r-TWT signaling information may be carried in one or more packets transmitted by the AP associated with the OBSS to the wireless communication device. In some other implementations, the cooperative r-TWT signaling information may be carried in one or more management frames transmitted by the AP associated with the OBSS to one or more STAs associated with the OBSS. In some implementations, the cooperative r-TWT signaling information may be received from a STA associated with the BSS that overhears one or more management frames transmitted by the AP associated with the OBSS.

[0010] In some aspects, the method may further include transmitting r-TWT coordination information indicating a first r-TWT SP associated with the OBSS. In some implementations, the r-TWT schedule information and the r-TWT coordination information may be carried in a broadcast target wake time (TWT) information element (IE) included in one or more packets transmitted by the wireless communication device. In some other implementations, the r-TWT schedule information and the r-TWT coordination information may be carried in a broadcast TWT IE and a coordinated r-TWT IE, respectively, included in one or more packets transmitted by the wireless communication device, where the coordinated r-TWT IE is different from the broadcast TWT IE.

[0011] Another innovative aspect of the subject matter described in this disclosure may be implemented in a wireless communication device. In some implementations, the wireless communication device may include at least one processor and at least one memory communicatively coupled to the at least one processor and storing processor-readable code. In some implementations, execution of the processor-readable code by the at least one processor causes the wireless communication device to perform operations including receiving cooperative r-TWT signaling information associated with a first r-TWT SP associated with a BSS, transmitting r-TWT schedule information indicating a second r-TWT SP associated with a BSS associated with the wireless communication device based on the cooperative r-TWT signaling information, and communicating with one or more STAs during the second r-TWT SP based on a respective latency requirement of each of the one or more STAs.

[0012] Another innovative aspect of the subject matter described in this disclosure may be realized as a method of wireless communication. The method may be performed by a wireless communication device and may include transmitting first cooperative r-TWT signaling information indicating a first r-TWT SP associated with a first BSS, and transmitting second cooperative r-TWT signaling information indicating a second r-TWT SP associated with a second BSS based on the first r-TWT SP. In some aspects, the first r-TWT SP may be orthogonal in time to the second r-TWT SP.

[0013]

[0013] In some other aspects, the first r-TWT SP may overlap in time with the second r-TWT SP. In some implementations, the first coordinated r-TWT signaling information may indicate a transmit power associated with a communication in a first BSS during the first r-TWT SP, and the second coordinated r-TWT signaling information may indicate a transmit power associated with a communication in a second BSS during the second r-TWT SP. In some other implementations, the first coordinated r-TWT signaling information may indicate an allocation of a first frequency resource for a communication in a first BSS during the first r-TWT SP, and the second coordinated r-TWT signaling information may indicate an allocation of a second frequency resource for a communication in a second BSS during the second r-TWT SP. In such implementations, the first frequency resource may be orthogonal to the second frequency resource.

[0014] In some implementations, the first and second cooperative r-TWT signaling information may be carried in a broadcast TWT IE included in one or more packets transmitted by the wireless communication device. In some other implementations, the first and second cooperative r-TWT signaling information may be carried in first and second cooperative r-TWT IEs, respectively, included in one or more packets transmitted by the wireless communication device.

[0015]

[0015] In some aspects, the method may further include transmitting r-TWT schedule information indicating a third r-TWT SP associated with a third BSS associated with the wireless communication device based on the first r-TWT SP and the second r-TWT SP, and communicating with one or more STAs during the third r-TWT SP based on respective latency requirements of each of the one or more STAs.

[0016] Another innovative aspect of the subject matter described in this disclosure may be implemented in a wireless communication device. In some implementations, the wireless communication device may include at least one processor and at least one memory communicatively coupled to the at least one processor and storing the processor-readable code. In some implementations, execution of the processor-readable code by the at least one processor causes the wireless communication device to perform operations including transmitting first cooperative r-TWT signaling information indicating a first r-TWT SP associated with a first BSS and transmitting second cooperative r-TWT signaling information indicating a second r-TWT SP associated with a second BSS based on the first r-TWT SP. [Brief description of the drawings]

[0017]

[0017] Details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the following description. Other features, aspects, and advantages will become apparent from the description, drawings, and claims. Please note that the relative dimensions of the following figures may not be drawn to scale.

[0018] [Figure 1]

[0018] An illustration of an exemplary wireless communication network is shown. [Figure 2A]

[0019] 1 illustrates an exemplary protocol data unit (PDU) that may be used for communication between an access point (AP) and one or more wireless stations (STAs). [Figure 2B]

[0020] 2B illustrates exemplary fields within the PDU of FIG. 2A. [Diagram 3]

[0021] 1 illustrates an example physical layer convergence protocol (PLCP) protocol data unit (PPDU) that can be used for communication between an AP and one or more STAs. [Figure 4]

[0022] 1 illustrates a block diagram of an exemplary wireless communication device. [Figure 5A]

[0023] 1 shows a block diagram of an exemplary AP. [Figure 5B]

[0024] 1 shows a block diagram of an exemplary STA. [Figure 6]

[0025] FIG. 1 shows a timing diagram illustrating example wireless communications associated with a basic service set (BSS) supporting restricted target wake time (r-TWT) operation. [Figure 7]

[0026] 1 illustrates an example communication environment having overlapping basic service sets (OBSS), according to some implementations. [Figure 8]

[0027] 1 shows a timing diagram illustrating example wireless communications associated with an OBSS supporting r-TWT operation, according to some implementations. [Figure 9]

[0028] 1 shows a timing diagram illustrating example wireless communications associated with an OBSS supporting r-TWT operation, according to some implementations. [Figure 10A]

[0029] 1 shows a sequence diagram illustrating an example message exchange between OBSSs supporting coordinated scheduling of r-TWT service periods (SPs) according to some implementations. [Figure 10B]

[0030] 1 shows a sequence diagram illustrating an example message exchange between OBSSs supporting cooperative scheduling of r-TWT SPs according to some implementations. [Figure 11A]

[0031] 1 shows a sequence diagram illustrating an example message exchange between OBSSs supporting cooperative scheduling of r-TWT SPs according to some implementations. [Figure 11B]

[0032] 1 shows a sequence diagram illustrating an example message exchange between OBSSs supporting cooperative scheduling of r-TWT SPs according to some implementations. [Figure 12]

[0033] 1 illustrates an example packet that may be used for coordinated r-TWT signaling between one or more APs and one or more STAs, according to some implementations. [Figure 13]

[0034] 13 illustrates another example packet that may be used for coordinated r-TWT signaling between one or more APs and one or more STAs, according to some implementations. [Figure 14]

[0035] 1 shows a flowchart illustrating an example process for wireless communication supporting coordinated scheduling and signaling of r-TWT SPs. [Figure 15A]

[0036] 1 shows a flowchart illustrating an example process for wireless communication supporting coordinated scheduling and signaling of r-TWT SPs. [Figure 15B]

[0037] 1 shows a flowchart illustrating an example process for wireless communication supporting coordinated scheduling and signaling of r-TWT SPs. [Figure 16]

[0038] 1 shows a block diagram of an example wireless communication device according to some implementations. [Figure 17]

[0039] 1 shows a block diagram of an example wireless communication device according to some implementations.

[0019]

[0040] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020]

[0041] The following description is directed to several implementations for the purpose of describing the innovative aspects of the present disclosure. However, those skilled in the art will readily recognize that the teachings herein can be applied in many different ways. The described implementations can be realized in any device, system, or network capable of transmitting and receiving radio frequency (RF) signals according to one or more of the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, the IEEE 802.15 standard, the Bluetooth standard defined by the Bluetooth Special Interest Group (SIG), or the Long Term Evolution (LTE), 3G, 4G, or 5G (New Radio (NR)) standards promulgated by the 3rd Generation Partnership Project (3GPP), among others. The described implementations may be realized in any device, system, or network capable of transmitting and receiving RF signals according to one or more of the following technologies or techniques: code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), single-user (SU) multiple-input multiple-output (MIMO), and multi-user (MU) MIMO.The described implementations may also be realized using other wireless communications protocols or RF signals suitable for use in one or more of a wireless personal area network (WPAN), a wireless local area network (WLAN), a wireless wide area network (WWAN), or an internet of things (IOT) network.

[0021]

[0042] The IEEE 802.11be amendment to the IEEE 802.11 standard describes a restricted target wake time (r-TWT) service period (SP) that may be allocated to latency-sensitive traffic. As used herein, the term "non-legacy STA" refers to any wireless station (STA) that supports the amendment IEEE 802.11be or a future generation of the IEEE 802.11 standard, while the term "low latency STA" refers to any non-legacy STA that has latency-sensitive traffic to transmit or receive. In contrast, the term "legacy STA" may refer to any STA that supports only IEEE 802.11ax or an earlier generation of the IEEE 802.11 standard. Non-legacy STAs that support r-TWT operation and acquire transmit opportunities (TXOPs) outside of an r-TWT SP must terminate their respective TXOPs prior to the start of an r-TWT SP of which they are not a member. Additionally, the AP may throttle traffic from all legacy STAs during the r-TWT SP by scheduling quiet intervals to overlap with the r-TWT SP, so that the r-TWT SP may provide more reliable, more predictable latency, reduced worst-case latency, or reduced jitter for latency-sensitive traffic.

[0022]

[0043] Aspects of the present disclosure recognize that overlapping basic service sets (OBSSs) exist in many wireless communication environments, especially in dense or congested environments. An OBSS is any basic service set (BSS) that has overlapping coverage areas and operates on the same wireless channel as another BSS. Thus, wireless communications in a given BSS may interfere or collide with wireless communications in an OBSS, resulting in increased latency for communications in the BSS, the OBSS, or both. Wireless communication devices (including access points (APs) and STAs) that operate in accordance with existing versions of the IEEE 802.11 standard (including the initial release (R1) of the revised IEEE 802.11be) may not recognize latency-sensitive traffic in the OBSS. Accordingly, new communication protocols and signaling are required to prevent latency-sensitive traffic in a given BSS from interfering with or colliding with latency-sensitive traffic in the OBSS.

[0023]

[0044] Various aspects relate generally to protecting latency-sensitive communications during r-TWT SPs, and more specifically, to coordinated scheduling of r-TWT SPs between BSSs. In some aspects, a first AP may coordinate with a second AP in scheduling r-TWT SPs such that latency-sensitive traffic in the first BSS does not interfere or collide with latency-sensitive traffic in a second BSS that overlaps with the first BSS. In some implementations, the first and second APs may schedule their respective r-TWT SPs to be orthogonal in time. In some other implementations, the first and second APs may schedule their r-TWT SPs to overlap in time when allocating coordinated resources to simultaneous or overlapping latency-sensitive traffic in the first and second BSSs (e.g., according to one or more multi-AP coordination techniques). In some aspects, the coordinated r-TWT SPs may be scheduled by a central coordinator (e.g., an AP or a network controller). For example, the central coordinator may communicate a cooperative r-TWT SP schedule to each of the first and second APs. In some other aspects, the cooperative r-TWT SPs may be scheduled in a distributed manner. For example, a first AP may communicate its r-TWT SP schedule to a second AP, and the second AP may schedule its r-TWT SPs based on the r-TWT SP schedule of the first AP.

[0024]

[0045] Particular implementations of the subject matter described in this disclosure may be realized to achieve one or more of the following potential advantages: By scheduling r-TWT SPs among multiple APs belonging to an OBSS in a cooperative manner, aspects of the present disclosure may significantly improve the latency gain achievable by latency-sensitive traffic through the application of r-TWT SPs. As explained above, simultaneous data transmissions in an OBSS may interfere or collide with one another, thereby increasing the latency of communications in such OBSSs. By scheduling r-TWT SPs that are orthogonal in time, aspects of the present disclosure may ensure that latency-sensitive data transmissions in a given BSS occur at different times than latency-sensitive data transmissions in an OBSS, thereby avoiding interference or collisions between OBSSs. By allocating cooperative resources to latency-sensitive traffic in different OBSSs, aspects of the present disclosure may enable simultaneous transmission of latency-sensitive traffic within the same or shared r-TWT SPs (e.g., at relatively low power or on orthogonal time or frequency resources). Therefore, as a result of cooperative scheduling, the r-TWT SP may provide more reliable, more predictable latency, reduced worst-case latency, or reduced jitter to latency-sensitive traffic in the OBSS.

[0025]

[0046] FIG. 1 illustrates a block diagram of an exemplary wireless communication network 100. According to some aspects, the wireless communication network 100 may be an example of a wireless local area network (WLAN), such as a Wi-Fi network (and hereinafter referred to as WLAN 100). For example, the WLAN 100 may be a network implementing at least one of the IEEE 802.11 family of wireless communication protocol standards (as defined in the IEEE 802.11-2020 specification or amendments thereof, including but not limited to 802.11ah, 802.11ad, 802.11ay, 802.11ax, 802.11az, 802.11ba, and 802.11be). The WLAN 100 may include multiple wireless communication devices, such as an access point (AP) 102 and multiple stations (STAs) 104. Although only one AP 102 is shown, the WLAN network 100 may include multiple APs 102.

[0026]

[0047] Each of the STAs 104 may also be referred to as a mobile station (MS), mobile device, mobile handset, wireless handset, access terminal (AT), user equipment (UE), subscriber station (SS), or subscriber unit, among other possible examples. The STAs 104 may represent a variety of devices, such as mobile phones, personal digital assistants (PDAs), other handheld devices, netbooks, notebook computers, tablet computers, laptops, display devices (e.g., TVs, computer monitors, navigation systems, among others), music or other audio or stereo devices, remote control devices ("remotes"), printers, kitchen appliances or other household appliances, key fobs (e.g., for passive keyless entry and start (PKES) systems), among other possible examples.

[0027]

[0048] A single AP 102 and an associated set of STAs 104 may be referred to as a basic service set (BSS) managed by each AP 102. FIG. 1 additionally illustrates an example coverage area 108 of the AP 102, which may represent a basic service area (BSA) of the WLAN 100. The BSS may be identified to users by a service set identifier (SSID) and to other devices by a basic service set identifier (BSSID), which may be the medium access control (MAC) address of the AP 102. The AP 102 periodically broadcasts a beacon frame ("beacon") containing the BSSID to enable any STAs 104 within wireless range of the AP 102 to "associate" or reassociate with the AP 102 to establish a respective communication link 106 (hereinafter also referred to as a "Wi-Fi link") with the AP 102 or to maintain a communication link 106 with the AP 102. For example, the beacon may include an identification of the primary channel used by each AP 102, as well as a timing synchronization function to establish or maintain timing synchronization with the AP 102. The APs 102 may provide access to external networks to various STAs 104 in the WLAN via respective communication links 106.

[0028]

[0049] To establish a communication link 106 with an AP 102, each of the STAs 104 is configured to perform passive or active scanning operations ("scans") on frequency channels within one or more frequency bands (e.g., the 2.4 GHz, 5 GHz, 6 GHz, or 60 GHz bands). To perform passive scanning, the STAs 104 listen for beacons transmitted by the respective APs 102 at regular time intervals called target beacon transmission times (TBTTs) (measured in time units (TUs), where one TU may equal 1024 microseconds (μs)). To perform active scanning, the STAs 104 generate probe requests and transmit them continuously on each channel to be scanned, and listen for probe responses from the APs 102. Each STA 104 may be configured to perform authentication and association operations to identify or select an AP 102 to associate with based on scan information obtained through passive or active scanning, and establish a communication link 106 with the selected AP 102. Upon completing the association operation, the AP 102 assigns an association identifier (AID) to the STA 104, which the AP 102 uses to track the STA 104.

[0029]

[0050] As a result of the increasing ubiquity of wireless networks, a STA 104 may have the opportunity to select one of many BSSs within range of the STA, or among multiple APs 102 that together form an extended service set (ESS) that includes multiple connected BSSs. The extended network stations associated with the WLAN 100 may be connected to a wired or wireless distribution system that may allow multiple APs 102 to be connected in such an ESS. Thus, a STA 104 may be covered by more than one AP 102 and may associate with different APs 102 at different times for different transmissions. Additionally, after association with an AP 102, the STA 104 may also be configured to periodically scan its surroundings to find a more suitable AP 102 to associate with. For example, a STA 104 moving with respect to its associated AP 102 may perform a "roaming" scan to find another AP 102 with more desirable network characteristics, such as a greater received signal strength indicator (RSSI) or reduced traffic load.

[0030]

[0051] In some cases, the STAs 104 may form a network without involving the AP 102 or other devices other than the STAs 104 themselves. One example of such a network is an ad-hoc network (or wireless ad-hoc network). An ad-hoc network may alternatively be referred to as a mesh network or a peer-to-peer (P2P) network. In some cases, the ad-hoc network may be implemented within a larger wireless network, such as the WLAN 100. In such an implementation, the STAs 104 may be able to communicate with each other via the AP 102 using the communication link 106, but the STAs 104 may also communicate with each other directly via a direct wireless link 110. In addition, two STAs 104 may communicate via the direct communication link 110 regardless of whether both STAs 104 are associated with and served by the same AP 102. In such an ad-hoc system, one or more of the STAs 104 may assume the role filled by the AP 102 in the BSS. Such STAs 104 may be referred to as group owners (GOs) and may coordinate transmissions within the ad-hoc network. Examples of direct wireless links 110 include Wi-Fi direct connections, connections established by using Wi-Fi Tunneled Direct Link Setup (TDLS) links, and other P2P group connections.

[0031]

[0052] The AP 102 and the STAs 104 may function and communicate (via their respective communication links 106) in accordance with the IEEE 802.11 family of wireless communication protocol standards (such as those defined in the IEEE 802.11-2016 specification or amendments thereto, including, but not limited to, 802.11ah, 802.11ad, 802.11ay, 802.11ax, 802.11az, 802.11ba, and 802.11be). These standards define WLAN radio and baseband protocols for the PHY layer and medium access control (MAC) layer. The AP 102 and the STAs 104 transmit and receive wireless communications (hereinafter also referred to as "Wi-Fi communications") between each other in the form of Physical Layer Convergence Protocol (PLCP) Protocol Data Units (PPDUs). The AP 102 and the STAs 104 in the WLAN 100 may transmit PPDUs over an unlicensed spectrum, which may be a portion of a spectrum that includes frequency bands traditionally used by Wi-Fi technology, such as the 2.4 GHz band, the 5 GHz band, the 60 GHz band, the 3.6 GHz band, and the 700 MHz band. Some implementations of the AP 102 and the STAs 104 described herein may also communicate in other frequency bands, such as the 6 GHz band, which may support both licensed and unlicensed communications. The AP 102 and the STAs 104 may also be configured to communicate over other frequency bands, such as shared licensed frequency bands, in which multiple operators may have licenses to operate in the same or overlapping frequency bands.

[0032]

[0053] Each of the frequency bands may include multiple sub-bands or frequency channels. For example, PPDUs conforming to IEEE 802.11n, 802.11ac, 802.11ax, and 802.11be standard amendments may be transmitted over the 2.4 GHz, 5 GHz, or 6 GHz bands, each of which is divided into multiple 20 MHz channels. Thus, these PPDUs are transmitted over physical channels with a minimum bandwidth of 20 MHz, but larger channels may be formed through channel bonding. For example, PPDUs may be transmitted over physical channels with bandwidths of 40 MHz, 80 MHz, 160 MHz, or 320 MHz by bonding together multiple 20 MHz channels.

[0033]

[0054] Each PPDU is a composite structure that includes a PHY preamble and a payload in the form of a PHY service data unit (PSDU). Information provided in the preamble may be used by a receiving device to decode subsequent data in the PSDU. In instances where a PPDU is transmitted over bonded channels, the preamble field may be duplicated and transmitted in each of the multiple constituent channels. The PHY preamble may include both a legacy portion (or "legacy preamble") and a non-legacy portion (or "non-legacy preamble"). The legacy preamble may be used for packet detection, automatic gain control, and channel estimation, among other applications. The legacy preamble may also generally be used to maintain compatibility with legacy devices. The format, coding, and information provided therein of the non-legacy portion of the preamble is based on the particular IEEE 802.11 protocol that will be used to transmit the payload.

[0034]

[0055] 2A illustrates an exemplary protocol data unit (PDU) 200 usable for wireless communication between an AP 102 and one or more STAs 104. For example, the PDU 200 may be configured as a PPDU. As shown, the PDU 200 includes a PHY preamble 202 and a PHY payload 204. For example, the preamble 202 may include a legacy portion that itself includes a legacy short training field (L-STF) 206, which may consist of two BPSK symbols, a legacy long training field (L-LTF) 208, which may consist of two BPSK symbols, and a legacy signal field (L-SIG) 210, which may consist of two BPSK symbols. The legacy portion of the preamble 202 may be configured in accordance with the IEEE 802.11a wireless communication protocol standard. The preamble 202 may also include a non-legacy portion that includes one or more non-legacy fields 212 that conform to an IEEE wireless communication protocol, such as, for example, an IEEE 802.11ac, 802.11ax, 802.11be, or later wireless communication protocol standard.

[0035]

[0056] The L-STF 206 generally enables the receiving device to perform automatic gain control (AGC) and coarse timing and frequency estimation. The L-LTF 208 generally enables the receiving device to perform fine timing and frequency estimation, and also enables the receiving device to perform an initial estimation of the wireless channel. The L-SIG 210 generally enables the receiving device to determine the duration of a PDU and use the determined duration to avoid transmitting over the PDU. For example, the L-STF 206, the L-LTF 208, and the L-SIG 210 may be modulated according to a binary phase shift keying (BPSK) modulation scheme. The payload 204 may be modulated according to a BPSK modulation scheme, a quadrature BPSK (Q-BPSK) modulation scheme, a quadrature amplitude modulation (QAM) modulation scheme, or another suitable modulation scheme. The payload 204 may include a PSDU that includes a data field (DATA) 214, which may carry higher layer data, for example in the form of Medium Access Control (MAC) protocol data units (MPDUs) or aggregated MPDUs (A-MPDUs).

[0036]

[0057] 2B illustrates an example L-SIG 210 in the PDU 200 of FIG. 2A. The L-SIG 210 includes a data rate field 222, a reserved bit 224, a length field 226, a parity bit 228, and a tail field 230. The data rate field 222 indicates a data rate (note that the data rate indicated in the data rate field 212 may not be the actual data rate of the data carried in the payload 204). The length field 226 indicates the length of the packet, for example, in units of symbols or bytes. The parity bit 228 may be used to detect bit errors. The tail field 230 includes tail bits that may be used by a receiving device to terminate the operation of a decoder (e.g., a Viterbi decoder). The receiving device may utilize the data rate and length indicated in the data rate field 222 and the length field 226 to determine the duration of the packet, for example, in units of microseconds (μs) or other time units.

[0037]

[0058] 3 illustrates an exemplary PPDU 300 that may be used for communication between an AP 102 and one or more STAs 104. As discussed above, each PPDU 300 includes a PHY preamble 302 and a PSDU 304. Each PSDU 304 may represent (or "carry") one or more MAC Protocol Data Units (MPDUs) 316. For example, each PSDU 304 may carry an aggregate MPDU (A-MPDU) 306 that includes an aggregation of multiple A-MPDU subframes 308. Each A-MPDU subframe 306 may include an MPDU frame 310 that includes a MAC delimiter 312 and a MAC header 314 prior to an associated MPDU 316 that comprises a data portion ("payload" or "frame body") of the MPDU frame 310. Each MPDU frame 310 may include a frame check sequence (FCS) field 318 for error detection (e.g., the FCS field may include a cyclic redundancy check (CRC)) and padding bits 320. The MPDU 316 may carry one or more MAC service data units (MSDUs) 326. For example, the MPDU 316 may carry an aggregate MSDU (A-MSDU) 322 that includes multiple A-MSDU subframes 324. Each A-MSDU subframe 324 includes a corresponding MSDU 330 preceded by a subframe header 328 and possibly followed by padding bits 332.

[0038]

[0059] Referring again to the MPDU frame 310, the MAC delimiter 312 serves as a marker of the start of the associated MPDU 316 and may indicate the length of the associated MPDU 316. The MAC header 314 may include multiple fields containing information that defines or indicates characteristics or attributes of the data encapsulated within the frame body 316. The MAC header 314 includes a duration field that indicates a duration that lasts from the end of the PPDU to at least the end of an acknowledgment (ACK) or Block ACK (BA) of the PPDU to be transmitted by the receiving wireless communication device. The use of the duration field helps to reserve the wireless medium for the indicated duration, allowing the receiving device to establish its network allocation vector (NAV). The MAC header 314 also includes one or more fields that indicate the address of the data encapsulated within the frame body 316. For example, the MAC header 314 may include a combination of a source address, a transmitter address, a receiver address, or a destination address. The MAC header 314 may further include a frame control field that includes control information. The frame control field may specify the frame type, for example, a data frame, a control frame, or a management frame.

[0039]

[0060] 4 shows a block diagram of an example wireless communication device 400. In some implementations, the wireless communication device 400 may be an example of a device for use in a STA, such as one of the STAs 104 described with reference to FIG 1. In some implementations, the wireless communication device 400 may be an example of a device for use in an AP, such as the AP 102 described with reference to FIG 1. The wireless communication device 400 is capable of transmitting (or outputting for transmission) and receiving wireless communications (e.g., in the form of wireless packets). For example, a wireless communication device may be configured to transmit and receive packets in the form of Physical Layer Convergence Protocol (PLCP) Protocol Data Units (PPDUs) and Medium Access Control (MAC) Protocol Data Units (MPDUs) that conform to IEEE 802.11 wireless communications protocol standards, such as those defined in the IEEE 802.11-2016 specification or amendments thereof, including, but not limited to, 802.11ah, 802.11ad, 802.11ay, 802.11ax, 802.11az, 802.11ba, and 802.11be.

[0040]

[0061] The wireless communication device 400 may be or include a chip, system on chip (SoC), chipset, package, or device including one or more modems 402, such as a Wi-Fi (IEEE 802.11 compliant) modem. In some implementations, the one or more modems 402 (collectively "modems 402") additionally include a WWAN modem (e.g., a 3GPP 4G LTE or 5G compliant modem). In some implementations, the wireless communication device 400 also includes one or more radios 404 (collectively "radios 404"). In some implementations, the wireless communication device 406 further includes one or more processors, processing blocks or processing elements 406 (collectively "processors 406") and one or more memory blocks or elements 408 (collectively "memory 408").

[0041]

[0062] The modem 402 may include an intelligent hardware block or device, such as, for example, an application-specific integrated circuit (ASIC), among other possible examples. The modem 402 is generally configured to implement a PHY layer. For example, the modem 402 is configured to modulate packets and output the modulated packets to the radio 404 for transmission over a wireless medium. The modem 402 is similarly configured to obtain modulated packets received by the radio 404 and demodulate the packets to provide demodulated packets. In addition to the modulator and demodulator, the modem 402 may further include digital signal processing (DSP) circuitry, an automatic gain control (AGC), a coder, a decoder, a multiplexer, and a demultiplexer. For example, while in a transmit mode, data obtained from the processor 406 is provided to a coder, which encodes the data to provide coded bits. The coded bits are then mapped to points in a modulation constellation (using a selected MCS) to provide modulated symbols. The modulated symbols are then N SS number of spatial streams or N STSThe modulated symbols in each spatial or space-time stream may then be multiplexed and converted via an inverse fast Fourier transform (IFFT) block, followed by being provided to a DSP circuit for TX windowing and filtering. The digital signal may then be provided to a digital-to-analog converter (DAC). The resulting analog signal may then be provided to a frequency up-converter and ultimately to the radio 404. In an implementation involving beamforming, the modulated symbols in each spatial stream are precoded via a steering matrix prior to their provision to the IFFT block.

[0042]

[0063] While in the receive mode, the digital signal received from the radio 404 is provided to the DSP circuit, which is configured to acquire the received signal, for example, by detecting the presence of a signal and estimating an initial timing and frequency offset. The DSP circuit is further configured to digitally condition the digital signal, for example, using channel (narrowband) filtering, analog impairment adjustment (such as correcting I / Q imbalance), and finally applying a digital gain to obtain a narrowband signal. The output of the DSP circuit may then be provided to an AGC, which is configured to use information extracted from the digital signal in one or more received training fields, for example, to determine an appropriate gain. The output of the DSP circuit is also coupled to a demodulator, which is configured to extract modulated symbols from the signal and calculate, for example, logarithm likelihood ratios (LLRs) for each bit position of each subcarrier in each spatial stream. The demodulator is coupled to a decoder, which may be configured to process the LLRs to provide decoded bits. The decoded bits from all of the spatial streams are then provided to a demultiplexer for demultiplexing, which may then be descrambled and provided to the MAC layer (processor 406) for processing, evaluation, or interpretation.

[0043]

[0064] The radio 404 generally includes at least one radio frequency (RF) transmitter (or “transmitter chain”) and at least one RF receiver (or “receiver chain”), which may be combined into one or more transceivers. For example, the RF transmitter and RF receiver may each include various DSP circuits, including at least one power amplifier (PA) and at least one low-noise amplifier (LNA). The RF transmitter and RF receiver may then be coupled to one or more antennas. For example, in some implementations, the wireless communication device 400 may include or be coupled to multiple transmit antennas (each with a corresponding transmit chain) and multiple receive antennas (each with a corresponding receive chain). Symbols output from the modem 402 are provided to the radio 404, which then transmits the symbols via the coupled antenna. Similarly, symbols received via the antennas are obtained by the radio 404, which then provides the symbols to the modem 402.

[0044]

[0065] The processor 406 may include intelligent hardware blocks or devices, such as, for example, a processing core, processing block, central processing unit (CPU), microprocessor, microcontroller, digital signal processor (DSP), application specific integrated circuit (ASIC), programmable logic device (PLD) such as field programmable gate array (FPGA), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The processor 406 processes information received via the radio 404 and modem 402, and processes information to be output via the modem 402 and radio 404 for transmission over a wireless medium. For example, the processor 406 may implement a control plane and MAC layer configured to perform various operations related to the generation and transmission of MPDUs, frames, or packets. The MAC layer is configured to perform or facilitate frame coding and decoding, spatial multiplexing, space-time block coding (STBC), beamforming, and OFDMA resource allocation, among other operations or techniques. In some implementations, the processor 406 may generally control the modem 402 to cause the modem to perform various operations described above.

[0045]

[0066] The memory 408 may include a tangible storage medium, such as a random-access memory (RAM) or a read-only memory (ROM), or a combination thereof. The memory 408 may also store non-transitory processor or computer-executable software (SW) code that includes instructions that, when executed by the processor 406, cause the processor to perform various operations described herein for wireless communication, including generating, transmitting, receiving, and interpreting MPDUs, frames, or packets. For example, various functions of the components disclosed herein, or various blocks or steps of the methods, operations, processes, or algorithms disclosed herein, may be implemented as one or more modules of one or more computer programs.

[0046]

[0067] FIG. 5A illustrates a block diagram of an exemplary AP 502. For example, the AP 502 may be an exemplary implementation of the AP 102 described with reference to FIG. 1. The AP 502 includes a wireless communication device (WCD) 510 (although the AP 502 itself may also be generally referred to as a wireless communication device as used herein). For example, the wireless communication device 510 may be an exemplary implementation of the wireless communication device 400 described with reference to FIG. 4. The AP 502 also includes multiple antennas 520 coupled to the wireless communication device 510 for transmitting and receiving wireless communications. In some implementations, the AP 502 additionally includes an application processor 530 coupled to the wireless communication device 510 and a memory 540 coupled to the application processor 530. The AP 502 further includes at least one external network interface 550 that enables the AP 502 to communicate with a core network or a backhaul network to provide access to external networks, including the Internet. For example, the external network interface 550 may include one or both of a wired (e.g., Ethernet) network interface and a wireless network interface (such as a WWAN interface). Some of the above-mentioned components may communicate directly or indirectly with some of the other components via at least one bus. The AP 502 further includes a housing that contains the wireless communication device 510, the application processor 530, the memory 540, and at least a portion of the antenna 520 and the external network interface 550.

[0047]

[0068] FIG. 5B illustrates a block diagram of an exemplary STA 504. For example, the STA 504 may be an exemplary implementation of the STA 104 described with reference to FIG. 1. The STA 504 includes a wireless communication device 515 (although the STA 504 itself may also be generally referred to as a wireless communication device as used herein). For example, the wireless communication device 515 may be an exemplary implementation of the wireless communication device 400 described with reference to FIG. 4. The STA 504 also includes one or more antennas 525 coupled with the wireless communication device 515 for transmitting and receiving wireless communications. The STA 504 additionally includes an application processor 535 coupled with the wireless communication device 515 and a memory 545 coupled with the application processor 535. In some implementations, the STA 504 further includes a user interface (UI) 555 (such as a touch screen or keypad) and a display 565, which may be integrated with the UI 555 to form a touch screen display. In some implementations, the STA 504 may further include one or more sensors 575, such as, for example, one or more inertial sensors, accelerometers, temperature sensors, pressure sensors, or altitude sensors. Some of the above-mentioned components may communicate directly or indirectly with other components via at least one bus. The STA 504 further includes a housing that contains the wireless communication device 515, the application processor 535, the memory 545, and at least a portion of the antenna 525, the UI 555, and the display 565.

[0048]

[0069] The IEEE 802.11be amendment to the IEEE 802.11 standard describes a restricted target wake time (r-TWT) service period (SP) that may be allocated for latency-sensitive traffic. As used herein, the term "non-legacy STA" refers to any STA that supports the amendment IEEE 802.11be or a future generation of the IEEE 802.11 standard, while the term "low latency STA" refers to any non-legacy STA that has latency-sensitive traffic to transmit or receive. In contrast, the term "legacy STA" may refer to any STA that only supports IEEE 802.11ax or an earlier generation of the IEEE 802.11 standard. Non-legacy STAs that support r-TWT operation and acquire TXOPs outside of an r-TWT SP must terminate their respective TXOPs prior to the start of an r-TWT SP of which they are not a member. Additionally, the AP may suppress traffic from all legacy STAs during the r-TWT SP by scheduling quiet intervals to overlap with the r-TWT SP, so that the r-TWT SP may provide more reliable, more predictable latency, reduced worst-case latency, or reduced jitter for latency-sensitive traffic.

[0049]

[0070] FIG. 6 shows a timing diagram 600 illustrating an example wireless communication associated with a BSS supporting r-TWT operation. In the example of FIG. 6, the BSS may include multiple non-legacy STAs 602 and 604 that support r-TWT operation. More specifically, the STA 602 receives a r-TWT signal at time t 3 From 86A and 6B, while STA 604 may be a low latency STA that is a member of the r-TWT SP for a duration up to 10 ms, while STA 604 may be a non-member STA. In some implementations, each of STAs 602 and 604 may be an example of either STA 104 or 504 of Figures 1 and 5B, respectively. Although two non-legacy STAs 602 and 604 are shown in the example of Figure 6 in an actual implementation, the BSS may include any number of legacy or non-legacy STAs.

[0050]

[0071] The non-member STAs 604 attempt to access the shared wireless channel prior to the start of the r-TWT SP. More specifically, the non-member STAs 604 determine based on a channel sensing operation (e.g., clear channel assessment (CCA)) that the non-member STAs 604 will not access the shared wireless channel until a time t 0 From 1 t t t t t 1 From 2 Count down the random backoff (RBO) duration until the threshold duration (time t 0 From 1 The RBO duration (up to time t 1 From 2 The time t 2 At time t , the non-member STA 604 detects that the wireless channel is still idle and proceeds to acquire a TXOP, for example, by starting transmission over the shared channel. In the example of FIG. 6, the desired TXOP is obtained at time t 3However, since the existing rules for r-TWT operation require that non-member STAs terminate their TXOPs at the start of an r-TWT SP, the non-member STAs 604 may not terminate their TXOPs until time t 2 and 3 The TXOP must be shortened between

[0051]

[0072] The low-latency STA 602 attempts to access the shared wireless channel at the beginning of the r-TWT SP. In the example of FIG. 6, the low-latency STA 602 attempts to access the shared wireless channel at time t 3 From 4 Detects that the channel is idle for an AIFS duration up to and including time t 4 From 6 As shown in FIG. 6, the non-member STA 604 also attempts to access the shared wireless channel at the start of the r-TWT SP. For example, the non-member STA 604 counts down the TXOP duration until the 3 From 5 Detects that the channel is idle for an AIFS duration up to time t 5 In some implementations, the data traffic associated with the low-latency STAs 602 may be assigned to a higher priority AC than the data traffic associated with the non-member STAs 604. Thus, the AIFS or RBO duration associated with the low-latency STAs 602 may be shorter than the AIFS or RBO duration associated with the non-member STAs 604, respectively. As a result, the low-latency STAs 602 count down the RBO duration starting at time t 6 In, a mobile station wins access to the wireless channel and obtains a TXOP, for example by initiating a transmission over the shared channel.

[0052]

[0073] The non-member STA 604 receives the 6At , it detects that the wireless medium is busy and holds the TXOP for the duration (t 6 From 7 After the TXOP ends, the 7 At time t , the non-member STA 604 may once again attempt to access the wireless channel. In this manner, r-TWT operation may prioritize latency-sensitive traffic in the BSS, for example, by requiring other non-member STAs to end their TXOPs at the beginning of an r-TWT SP of which they are not members. Furthermore, the AP (not shown for simplicity) may request that the AP terminate their TXOPs at at least a portion of the r-TWT SP (time t 3 A BSS may suppress all traffic from legacy STAs associated with the BSS by scheduling a quiet interval to overlap with a r-TWT SP (e.g., one or more time units (TUs) following a r-TWT SP). For example, the duration of the quiet interval may be indicated by one or more quiet elements included in management frames (e.g., beacon and probe response frames) transmitted by the AP prior to the start of the r-TWT SP.

[0053]

[0074] As described above, OBSSs exist in many wireless communication environments, especially in dense or congested environments. An OBSS is any BSS that has overlapping coverage areas and operates on the same wireless channel as another BSS. Thus, wireless communications in a given BSS may interfere or collide with wireless communications in an OBSS, resulting in increased latency for communications in the BSS, the OBSS, or both. Wireless communication devices (including APs and STAs) that operate according to existing versions of the IEEE 802.11 standard (including the initial release (R1) of the revised IEEE 802.11be) may not recognize latency-sensitive traffic in an OBSS. Accordingly, new communication protocols and signaling are required to prevent latency-sensitive traffic in a given BSS from interfering or colliding with latency-sensitive traffic in an OBSS.

[0054]

[0075] Various aspects relate generally to latency-sensitive communications, and more specifically, to coordinating latency-sensitive communications between BSSs. In some aspects, a first AP may coordinate with a second AP in scheduling r-TWT SPs such that latency-sensitive traffic in the first BSS does not interfere or collide with latency-sensitive traffic in a second BSS that overlaps with the first BSS. In some implementations, the first and second APs may schedule their respective r-TWT SPs to be orthogonal in time. In some other implementations, the first and second APs may schedule their r-TWT SPs to overlap in time when allocating cooperative resources to simultaneous or overlapping latency-sensitive traffic in the first and second BSSs (e.g., according to one or more multi-AP cooperation techniques). In some aspects, the cooperative r-TWT SPs may be scheduled by a central coordinator (e.g., an AP or a network controller). For example, the central coordinator may communicate a cooperative r-TWT SP schedule to each of the first and second APs. In some other aspects, the cooperative r-TWT SPs may be scheduled in a distributed manner. For example, a first AP may communicate its r-TWT SP schedule to a second AP, and the second AP may schedule its r-TWT SPs based on the r-TWT SP schedule of the first AP.

[0055]

[0076] Particular implementations of the subject matter described in this disclosure may be realized to achieve one or more of the following potential advantages: By scheduling r-TWT SPs in a cooperative manner among multiple APs belonging to an OBSS, aspects of the present disclosure may significantly improve the latency gain achievable by latency-sensitive traffic through the application of r-TWT SPs. As explained above, simultaneous data transmissions in an OBSS may interfere or collide with one another, thereby increasing the latency of communications in such OBSSs. By scheduling r-TWT SPs that are orthogonal in time, aspects of the present disclosure may ensure that latency-sensitive data transmissions in a given BSS occur at different times than latency-sensitive data transmissions in an OBSS, thereby avoiding interference or collisions between OBSSs. By allocating cooperative resources to latency-sensitive traffic in different OBSSs, aspects of the present disclosure may enable simultaneous transmission of latency-sensitive traffic within the same or shared r-TWT SPs (e.g., at relatively low power or on orthogonal time or frequency resources). As a result of the cooperative scheduling, the r-TWT SP may provide more reliable, more predictable latency, reduced worst-case latency, or reduced jitter to latency-sensitive traffic within the OBSS.

[0056]

[0077] 7 illustrates an example communication environment 700 having an OBSS according to some implementations. More specifically, the example communication environment 700 includes several STAs 701-706 and several APs 711-713. In some implementations, each of the STAs 701-706 may be an example of either the STAs 104 or 504 of FIG. 1 and FIG. 5B, respectively. In some implementations, each of the APs 711-713 may be an example of either the APs 102 or 502 of FIG. 1 and FIG. 5A, respectively. The APs 711-713 may represent BSSs (BSS1-BSS3) having coverage areas 711-713, respectively.

[0057]

[0078] As shown in FIG. 7, STAs 701 and 702 are associated with AP 711 (or BSS1) and are located within coverage area 721, STAs 703-705 are associated with AP 712 (or BSS2) and are located within coverage area 722, and STA 706 is associated with AP 713 (or BSS3) and is located within coverage area 723. In the example of FIG. 7, each of APs 711-713 may be configured to operate on the same wireless channel. Furthermore, APs 711 and 712 have overlapping coverage areas 721 and 722, respectively. Thus, APs 711 and 712 represent OBSSs. Similarly, APs 712 and 713 have overlapping coverage areas 722 and 723, respectively. Thus, APs 712 and 713 represent OBSSs.

[0058]

[0079] In some aspects, each of the STAs 701-706 and each of the APs 711-713 may support r-TWT operation. More specifically, the AP 711 may schedule one or more r-TWT SPs that may be used by its associated STAs 701 and 702 to communicate latency-sensitive traffic, the AP 712 may schedule one or more r-TWT SPs that may be used by its associated STAs 703-705 to communicate latency-sensitive traffic, and the AP 713 may schedule one or more r-TWT SPs that may be used by its associated STAs 706 to communicate latency-sensitive traffic. Because BSS2 overlaps with BSS1 and BSS3, wireless communications in BSS2 may interfere or collide with wireless communications in either BSS1 or BSS3. Similarly, wireless communications in either BSS1 or BSS3 may interfere or collide with wireless communications in BSS2.

[0059]

[0080] In some aspects, the APs 711 and 712 may coordinate the scheduling of their respective r-TWT SPs to avoid interference or collisions between latency-sensitive data traffic in BSS1 and latency-sensitive data traffic in BSS2. Thus, the APs 711 and 712 may be referred to herein as "r-TWT coordinated APs." In some implementations, the APs 711 and 712 may schedule their respective r-TWT SPs to be orthogonal in time. For example, the AP 711 may schedule one or more r-TWT SPs to occur during a time period that does not overlap with any r-TWT SPs scheduled by the AP 712. Similarly, the AP 712 may schedule one or more r-TWT SPs to occur during a time period that does not overlap with any r-TWT SPs scheduled by the AP 711. In some other implementations, APs 711 and 712 may schedule their r-TWT SPs to overlap in time when allocating cooperative resources to simultaneous or overlapping latency-sensitive traffic in BSS1 and BSS2 (such as by using one or more multi-AP cooperation techniques). For example, within the same or overlapping r-TWT SPs, latency-sensitive traffic may be transmitted at relatively lower power or on different time or frequency resources across BSS1 and BSS2.

[0060]

[0081] In some aspects, the cooperative r-TWT SPs may be scheduled by a central coordinator. For example, the central coordinator may schedule r-TWT SPs for each of the APs 711 and 712 and communicate the r-TWT SP schedule to the APs 711 and 712 via cooperative r-TWT signaling. In some implementations, the central coordinator may be an AP, such as, for example, one of the APs 711 or 712. In some other implementations, the central coordinator may be a network controller that communicates with the APs 711 and 712 via a (wired or wireless) backhaul. In some other aspects, the cooperative r-TWT SPs may be scheduled in a distributed manner. For example, the AP 711 may communicate its r-TWT SP schedule to the AP 712, and the AP 712 may schedule its r-TWT SPs based on the r-TWT SP schedule of the AP 711. In some implementations, the AP 711 may "explicitly" signal its r-TWT SP schedule to the AP 712 over the wired backhaul or in one or more packets transmitted to (or intended for reception by) the AP 712. In some other implementations, the AP 711 may "implicitly" signal its r-TWT SP schedule to the AP 712. In such implementations, the AP 712 may obtain the r-TWT SP schedule of the AP 711 by eavesdropping on one or more packets transmitted by the AP 711 to its associated STAs (such as STAs 701 or 702).

[0061]

[0082] In some implementations, each of the r-TWT cooperative APs 711 and 712 may transmit or broadcast cooperative r-TWT signaling information to other APs or STAs in its vicinity. For example, the AP 711 may broadcast its r-TWT SP schedule as well as the r-TWT SP schedule of the AP 712 to its associated STAs 701 and 702, as well as to any other APs within wireless communication range. In response, the STAs 701 and 702 (with other APs) may schedule their latency-sensitive communications to occur simultaneously with the r-TWT SP of the AP 712, while avoiding the r-TWT SP of the AP 711. Similarly, the AP 712 may broadcast its r-TWT SP schedule as well as the r-TWT SP schedule of the AP 711 to its associated STAs 703-705 as well as to any other APs within wireless communication range. In response, STAs 703-705 may schedule their latency-sensitive communications to occur simultaneously with the r-TWT SP of AP 711 while avoiding the r-TWT SP of AP 712.

[0062]

[0083] In some aspects, the AP 713 may not coordinate the scheduling of its r-TWT SPs with the AP 712 (or may not support coordinated r-TWT scheduling). Thus, the AP 713 may be referred to herein as an "r-TWT non-cooperative AP." In some implementations, the AP 712 may obtain the AP 713's r-TWT SP schedule by eavesdropping on beacon frames, management frames, or other packets transmitted by the AP 713 to its associated STAs (such as the STA 706). In response, the AP 712 may schedule its r-TWT SPs based on the AP 713's r-TWT SP schedule. In some implementations, the AP 712 may schedule its r-TWT SPs to be orthogonal in time to (or avoid) the r-TWT SPs scheduled by the AP 713. In some other implementations, the AP 712 may utilize other information associated with the AP 713 in addition to the AP 713's r-TWT SP schedule when scheduling its own r-TWT SPs. For example, AP712 may assess the level of interference from AP713 based on a received signal strength indication (RSSI) of a wireless signal received from AP713 and may adjust the transmit power or timing of latency-sensitive traffic in BSS2 to avoid interference or collision with latency-sensitive traffic in BSS3.

[0063]

[0084] In some other aspects, the AP 713 may be hidden (or undetectable) from the AP 712. In some implementations, the AP 712 may obtain the r-TWT SP schedule of the AP 713 from one or more associated STAs (such as the STA 705) located within the coverage area 723 of the AP 713. For example, the STA 705 may eavesdrop on one or more beacon frames, management frames, or other packets transmitted by the AP 713 to its associated STAs (such as the STA 706). The STA 705 may analyze the eavesdropped packets for r-TWT schedule information indicative of the r-TWT SP schedule of the AP 713 and relay the r-TWT SP schedule to the AP 712. In response, the AP 712 may schedule its r-TWT SP based on the r-TWT SP schedule of the AP 713. In some implementations, AP712 may schedule its r-TWT SPs to be orthogonal in time with (or avoid) r-TWT SPs scheduled by AP713. In some other implementations, AP712 may utilize other information associated with AP713 (such as RSSI of wireless signals received from AP713) in addition to AP713's r-TWT SP schedule when scheduling its own r-TWT SPs. For example, AP712 may adjust the transmit power or timing of latency-sensitive traffic in BSS2 to avoid interference or collision with latency-sensitive traffic in BSS3.

[0064]

[0085] FIG. 8 shows a timing diagram 800 illustrating an example wireless communication associated with OBSSs (BSS1-BSS3) supporting r-TWT operation according to some implementations. In the example of FIG. 8, BSS1, BSS2, and BSS3 are represented by access points AP1, AP2, and AP3, respectively. In some implementations, access points AP1, AP2, and AP3 may be examples of APs 711, 712, and 713, respectively, of FIG. 7. As shown in FIG. 8, access points AP1 and AP2 belong to a cooperative r-TWT scheduling group. Thus, access points AP1 and AP2 may schedule their r-TWT SPs in a cooperative manner such that latency-sensitive data traffic in BSS1 does not interfere or collide with latency-sensitive data traffic in BSS2. In contrast, access point AP3 does not belong to a cooperative r-TWT scheduling group. Thus, access point AP3 does not schedule its r-TWT SPs in a cooperative manner with either access point AP1 or AP2.

[0065]

[0086] In some implementations, access points AP1 and AP2 may schedule their r-TWT SPs orthogonal in time while avoiding the r-TWT SPs scheduled by access point AP3. As shown in FIG. 8, access point AP3 schedules r-TWT SPs at time t 3 From 4 In response, the access points AP1 and AP2 schedule an r-TWT SP (r-TWT SP3) to occur by t 3 and 4 In the example of FIG. 8, the access point AP1 may avoid scheduling a time 1 From 2 The access point AP2 schedules the r-TWT SP (r-TWT SP1) to occur until t 2 From 3In some implementations, each of the service periods r-TWT SP1, r-TWT SP2, and r-TWT SP3 is scheduled to occur until time t 3 From 8 6 (up to 100 Mbps) in BSS1 during r-TWT SP1. Accordingly, a first access point AP1 may communicate latency-sensitive data with one or more low-latency STAs in BSS1 during r-TWT SP1, a second access point AP2 may communicate latency-sensitive data with one or more low-latency STAs in BSS2 during r-TWT SP2, and a third access point AP3 may communicate latency-sensitive data with one or more low-latency STAs in BSS3 during r-TWT SP3.

[0066]

[0087] Aspects of the present disclosure recognize that STAs located at the edge of an AP's coverage area (such as STAs 702, 703, and 705 in FIG. 7) are more susceptible to interference from OBSSs than STAs located closer to the AP. Thus, allocating such STAs to r-TWT SPs that are orthogonal in time may significantly improve the quality of their latency-sensitive data communications compared to other means of cooperative r-TWT scheduling. In some aspects, each of the access points AP1, AP2, and AP3 may assign or allocate low-latency STAs to service periods r-TWT SP1, r-TWT SP2, and r-TWT SP3, respectively, based on r-TWT schedule information carried in a beacon or other management frame transmitted prior to (or during) one or more r-TWT SPs. In some implementations, the r-TWT schedule information associated with a particular r-TWT SP may assign one or more STAs to that r-TWT SP. In some other implementations, a STA may request to join a particular r-TWT SP in response to receiving r-TWT schedule information associated with that r-TWT SP.

[0067]

[0088] As shown in FIG. 8, the access point AP1 0 At time t , the access point AP2 transmits a beacon frame 801 carrying r-TWT schedule information indicating a schedule associated with the r-TWT SP1. For example, referring to FIG. 7, the beacon frame 801 may be transmitted by the AP 711 to assign or allocate the STA 702 to the r-TWT SP1. 0 7, the access point AP3 may transmit a beacon frame 802 carrying r-TWT schedule information indicating a schedule associated with the r-TWT SP2. For example, referring to FIG. 7, the beacon frame 802 may be transmitted by the AP 712 and may assign or allocate one or more of the STAs 703 or 705 to the r-TWT SP2. 0 At the same time (t 0 ), in some other implementations, one or more of the beacon frames 801-803 may be transmitted at different times.

[0068]

[0089] In some implementations, the beacon frames 801 and 802 broadcast by the cooperative access points AP1 and AP2, respectively, may further carry cooperative r-TWT signaling information. As described above, the cooperative r-TWT signaling information may indicate an r-TWT SP schedule associated with one or more OBSSs. For example, the beacon frame 801 may carry cooperative r-TWT signaling information indicating a schedule for one or more of the service periods r-TWT SP2 or r-TWT SP3, and the beacon frame 802 may carry cooperative r-TWT signaling information indicating a schedule for one or more of the service periods r-TWT SP1 or r-TWT SP3. As used herein, the term "schedule" may include timing information, resource allocation information, or various other communication parameters associated with an r-TWT SP. For example, a schedule for r-TWT SP1 may indicate that r-TWT SP1 is scheduled to operate from time t 1 From 2 and the schedule for r-TWT SP2 can be shown to occur by time t 2 From 3 It can be shown that the schedule for r-TWT SP3 occurs by time t 3 From 4 It may be shown that the

[0069]

[0090] FIG. 9 shows a timing diagram 900 illustrating an example wireless communication associated with OBSSs (BSS1-BSS3) supporting r-TWT operation according to some implementations. In the example of FIG. 9, BSS1, BSS2, and BSS3 are represented by access points AP1, AP2, and AP3, respectively. In some implementations, access points AP1, AP2, and AP3 may be examples of APs 711, 712, and 713, respectively, of FIG. 7. As shown in FIG. 9, access points AP1 and AP2 belong to a cooperative r-TWT scheduling group. Thus, access points AP1 and AP2 may schedule their r-TWT SPs in a cooperative manner such that latency-sensitive data traffic in BSS1 does not interfere or collide with latency-sensitive data traffic in BSS2. In contrast, access point AP3 does not belong to a cooperative r-TWT scheduling group. Thus, access point AP3 does not schedule its r-TWT SPs in a cooperative manner with either access point AP1 or AP2.

[0070]

[0091] In some implementations, access points AP1 and AP2 may schedule their r-TWT SPs to overlap in time while avoiding the r-TWT SP scheduled by access point AP3. As shown in FIG. 9, access point AP3 schedules r-TWT SPs at time t 2 From 3 In response, the access points AP1 and AP2 schedule an r-TWT SP (r-TWT SP3) to occur by t 2 and 3 In the example of FIG. 9, access points AP1 and AP2 may avoid scheduling a time 1 From 2In some implementations, each of the service periods r-TWT SP1, r-TWT SP2, and r-TWT SP3 is scheduled to occur until time t 3 From 8 6 (up to 100 Mbps) in BSS1 during r-TWT SP1. Accordingly, a first access point AP1 may communicate latency-sensitive data with one or more low-latency STAs in BSS1 during r-TWT SP1, a second access point AP2 may communicate latency-sensitive data with one or more low-latency STAs in BSS2 during r-TWT SP2, and a third access point AP3 may communicate latency-sensitive data with one or more low-latency STAs in BSS3 during r-TWT SP3.

[0071]

[0092] In some aspects, to prevent latency-sensitive traffic in BSS1 from interfering or colliding with latency-sensitive traffic in BSS2, access points AP1 and AP2 may coordinate their allocation of resources for wireless communication during overlapping service periods r-TWT SP1 and r-TWT SP2. Exemplary suitable resources include transmit power, timing, or frequency allocations for latency-sensitive traffic, among other examples. In some implementations, access points AP1 and AP2 may coordinate the transmission times of wireless communication in BSS1 and BSS2 during r-TWT SP1 and r-TWT SP2. In such implementations, the timing of the latency-sensitive traffic in BSS1 may be orthogonal to the timing of the latency-sensitive traffic in BSS2. For example, each of access points AP1 and AP2 may initiate a TXOP during r-TWT SP1 and r-TWT SP2 by transmitting a multi-user (MU) request-to-send (RTS) frame requesting simultaneous clear-to-send (CTS) frames from multiple STAs, thereby protecting the TXOP from interference by STAs in the OBSS.

[0072]

[0093] In some other implementations, the access points AP1 and AP2 may coordinate frequency resources (e.g., RUs) allocated to wireless communications in BSS1 and BSS2 during r-TWT SP1 and r-TWT SP2. In such implementations, frequency resources allocated to latency-sensitive traffic in BSS1 may be orthogonal to frequency resources allocated to latency-sensitive traffic in BSS2. For example, prior to (or during) r-TWT SP1 and r-TWT SP2, the access points AP1 and AP2 may exchange coordination information indicating allocation of frequency resources for wireless communications in at least one of BSS1 or BSS2 (e.g., in accordance with coordinated OFDMA (C-OFDMA) operation). The access points AP1 and AP2 may utilize the coordination information exchange to propose, grant, or negotiate orthogonal frequency resources to be allocated to wireless communications in BSS1 and BSS2 during the overlapping service periods r-TWT SP1 and r-TWT SP2.

[0073]

[0094] Still further, in some implementations, access points AP1 and AP2 may coordinate transmit powers of wireless communications in BSS1 and BSS2 during r-TWT SP1 and r-TWT SP2. In such implementations, transmit powers of latency-sensitive traffic in BSS1 may be appropriately lowered so as not to interfere with latency-sensitive traffic in BSS2, and transmit powers of latency-sensitive traffic in BSS2 may be appropriately lowered so as not to interfere with latency-sensitive traffic in BSS1. For example, prior to (or during) r-TWT SP1 and r-TWT SP2, access points AP1 and AP2 may exchange coordination information indicating transmit powers to be used for wireless communications in at least one of BSS1 or BSS2 (such as in accordance with coordinated spatial reuse (C-SR) operation). Access points AP1 and AP2 may utilize cooperative information exchange to propose, agree, or negotiate a transmit power to be used for wireless communications in BSS1 and BSS2 during overlapping service periods r-TWT SP1 and r-TWT SP2.

[0074]

[0095] Aspects of the present disclosure recognize that STAs located near an AP (such as STAs 701 and 704 in FIG. 7) are more susceptible to interference from OBSSs than STAs located farther from the AP. Thus, lowering the transmission power of wireless communications associated with such STAs may effectively suppress interference between OBSSs in overlapping r-TWT SPs. In some aspects, each of the access points AP1, AP2, and AP3 may assign or allocate low-latency STAs to service periods r-TWT SP1, r-TWT SP2, and r-TWT SP3, respectively, based on r-TWT schedule information carried in a beacon or other management frame transmitted prior to (or during) one or more r-TWT SPs. In some implementations, the r-TWT schedule information associated with a particular r-TWT SP may assign one or more STAs to that r-TWT SP. In some other implementations, a STA may request to join a particular r-TWT SP in response to receiving r-TWT schedule information associated with that r-TWT SP.

[0075]

[0096] As shown in FIG. 9, the access point AP1 0 At time t , the access point AP2 transmits a beacon frame 901 carrying r-TWT schedule information indicating a schedule associated with the r-TWT SP1. For example, referring to FIG. 7, the beacon frame 901 may be transmitted by the AP 711 to assign or allocate the STA 701 to the r-TWT SP1. 0 At time t , the access point AP3 transmits a beacon frame 902 carrying r-TWT schedule information indicating a schedule associated with the r-TWT SP2. For example, referring to FIG. 7, the beacon frame 902 may be transmitted by the AP 712 to assign or allocate the STA 704 to the r-TWT SP2. 07, the STA 706 transmits a beacon frame 903 carrying r-TWT schedule information indicating a schedule associated with the r-TWT SP3. For example, referring to FIG. 7, the beacon frame 903 may assign or allocate the STA 706 to the r-TWT SP3. FIG. 9 shows a diagram of the STA 706 at the same time (t 0 ), in some other implementations, one or more of the beacon frames 901-903 may be transmitted at different times.

[0076]

[0097] In some implementations, the beacon frames 901 and 902 broadcast by the cooperative access points AP1 and AP2, respectively, may further carry cooperative r-TWT signaling information. As explained above, the cooperative r-TWT signaling information may indicate an r-TWT SP schedule associated with one or more OBSSs. For example, the beacon frame 901 may carry cooperative r-TWT signaling information indicating a schedule for one or more of the service periods r-TWT SP2 or r-TWT SP3, and the beacon frame 902 may carry cooperative r-TWT signaling information indicating a schedule for one or more of the service periods r-TWT SP1 or r-TWT SP3. More specifically, the schedule for r-TWT SP1 may indicate a schedule for r-TWT SP1 to be transmitted from time t 1 From 2 It can be shown that the schedule for r-TWT SP2 also occurs at time t 1 From 2 It can be shown that the schedule for r-TWT SP3 occurs until time t 2 From 3 It can be shown that up to

[0077]

[0098] 10A shows a sequence diagram 1000 illustrating an example message exchange between BSSs (BSS1 and BSS2) supporting cooperative scheduling of r-TWT SPs according to some implementations. As shown in FIG. 10A, BSS1 includes AP 1001 and STA 1003, and BSS2 includes AP 1002 and STA 1004. In some implementations, each of AP 1001 and 1002 may be an example of AP 711 and 712, respectively, in FIG. 7, STA 1003 may be an example of either STA 701 or 702, and STA 1004 may be an example of any of STAs 703 to 705.

[0078]

[0099] In some aspects, the network controller 1005 may coordinate the scheduling of r-TWT SPs for BSS1 and BSS2 such that latency-sensitive communications in BSS1 do not interfere or collide with latency-sensitive communications in BSS2. For example, the network controller 1005 may be coupled to or in communication with APs 1001 and 1002 via a backhaul (wired or wireless). In the example of FIG. 10A, the network controller 1005 may schedule a first r-TWT SP (r-TWT SP1) for BSS1 and a second r-TWT SP (r-TWT SP2) for BSS2. In some implementations, the r-TWT SP1 and the r-TWT SP2 may be orthogonal in time (as described with reference to FIG. 8). In some other implementations, the r-TWT SP1 and the r-TWT SP2 may overlap in time (as described with reference to FIG. 9). In such an implementation, the network controller 1005 may coordinate the allocation of resources (such as transmit power, timing, or frequency allocations) for wireless communications during overlapping service periods r-TWT SP1 and r-TWT SP2.

[0079]

[0100] The network controller 1005 communicates the cooperative r-TWT signaling information to each of the APs 1001 and 1002. More specifically, the cooperative r-TWT signaling information provided to the AP 1001 may include a schedule for r-TWT SP1, and the cooperative r-TWT signaling information provided to the AP 1002 may include a schedule for r-TWT SP2. In some implementations, the cooperative r-TWT signaling information provided to the AP 1001 may also include a schedule for r-TWT SP2, and the cooperative r-TWT signaling information provided to the AP 1002 may also include a schedule for r-TWT SP1.

[0080]

[0101] The AP 1001 schedules the r-TWT SP1 based on the received cooperative r-TWT signaling information and transmits or broadcasts r-TWT schedule information indicating the schedule for the r-TWT SP1. For example, the r-TWT schedule information may be carried in a broadcast r-TWT information element (IE) included in a beacon frame or other management frame transmitted by the AP 1001 to the STA 1003 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1001, the STA 1003 joins (as a member) the r-TWT SP1. In some implementations, the r-TWT schedule information may assign the STA 1003 to the r-TWT SP1. In some other implementations, the STA 1003 may request to join the r-TWT SP1 based on the received r-TWT schedule information. AP1001 and STA1003 may then exchange latency-sensitive traffic during r-TWT SP1.

[0081]

[0102] In some aspects, the AP 1001 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP2. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1001 to the STA 1003. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1001 to the STA 1003. Furthermore, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STA 1003 may schedule its communications based on the cooperative r-TWT signaling information to avoid interfering with latency-sensitive traffic in BSS2 (during r-TWT SP2).

[0082]

[0103] The AP 1002 schedules the r-TWT SP2 based on the received cooperative r-TWT signaling information and transmits or broadcasts r-TWT schedule information indicating the schedule for the r-TWT SP2. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1002 to the STAs 1004 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1002, the STAs 1004 join (as members) the r-TWT SP2. In some implementations, the r-TWT schedule information may assign the STA 1004 to the r-TWT SP2. In some other implementations, the STAs 1004 may request to join the r-TWT SP2 based on the received r-TWT schedule information. The AP 1002 and the STAs 1004 may then exchange latency-sensitive traffic during the r-TWT SP2.

[0083]

[0104] In some aspects, the AP 1002 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP1. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1002 to the STA 1004. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1002 to the STA 1004. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STA 1004 may schedule its communications to avoid interfering with latency-sensitive traffic in BSS1 (during r-TWT SP1) based on the cooperative r-TWT signaling information.

[0084]

[0105] 10B shows a sequence diagram 1010 illustrating an example message exchange between BSSs (BSS1 and BSS2) supporting cooperative scheduling of r-TWT SPs according to some implementations. As shown in FIG. 10B, BSS1 includes AP 1011 and STA 1013, and BSS2 includes AP 1012 and STA 1014. In some implementations, each of AP 1011 and 1012 may be an example of AP 711 and 712, respectively, of FIG. 7, STA 1013 may be an example of either STA 701 or 702, and STA 1014 may be an example of any of STAs 703 to 705.

[0085]

[0106] In some aspects, the AP 1011 may coordinate the scheduling of r-TWT SPs of BSS1 and BSS2 such that latency-sensitive communications in BSS1 do not interfere or collide with latency-sensitive communications in BSS2. In the example of FIG. 10B, the AP 1011 may schedule a first r-TWT SP (r-TWT SP1) for BSS1 and a second r-TWT SP (r-TWT SP2) for BSS2. In some implementations, the r-TWT SP1 and the r-TWT SP2 may be orthogonal in time (as described with reference to FIG. 8). In some other implementations, the r-TWT SP1 and the r-TWT SP2 may overlap in time (as described with reference to FIG. 9). In such implementations, the AP 1011 may coordinate the allocation of resources (such as transmit power, timing, or frequency allocation) for wireless communications during the overlapping service periods r-TWT SP1 and r-TWT SP2.

[0086]

[0107] The AP 1011 communicates the cooperative r-TWT signaling information to the AP 1012. In some implementations, the AP 1011 may communicate the cooperative r-TWT signaling information to the AP 1012 via a backhaul (wired or wireless). In some other implementations, the AP 1011 may transmit the cooperative r-TWT signaling information to the AP 1012 via one or more wireless communication packets or frames (such as a new action frame or an enhanced broadcast services (EBCS) frame). More specifically, the cooperative r-TWT signaling information may include a schedule for the r-TWT SP2. In some implementations, the cooperative r-TWT signaling information may also include a schedule for the r-TWT SP1.

[0087]

[0108] The AP 1011 further transmits or broadcasts r-TWT schedule information indicating a schedule for the r-TWT SP1. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1011 to the STA 1013 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1011, the STA 1013 joins (as a member) the r-TWT SP1. In some implementations, the r-TWT schedule information may assign the STA 1013 to the r-TWT SP1. In some other implementations, the STA 1013 may request to join the r-TWT SP1 based on the received r-TWT schedule information. The AP 1011 and the STA 1013 may then exchange latency-sensitive traffic during the r-TWT SP1.

[0088]

[0109] In some aspects, the AP 1011 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP2. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1011 to the STA 1013. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1011 to the STA 1013. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STA 1013 may schedule its communications to avoid interfering with latency-sensitive traffic in BSS2 (during r-TWT SP2) based on the cooperative r-TWT signaling information.

[0089]

[0110] The AP 1012 schedules the r-TWT SP2 based on the received cooperative r-TWT signaling information and transmits or broadcasts r-TWT schedule information indicating the schedule for the r-TWT SP2. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1012 to the STAs 1014 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1012, the STAs 1014 join (as members) the r-TWT SP2. In some implementations, the r-TWT schedule information may assign the STA 1014 to the r-TWT SP2. In some other implementations, the STAs 1014 may request to join the r-TWT SP2 based on the received r-TWT schedule information. The AP 1012 and the STAs 1014 may then exchange latency-sensitive traffic during the r-TWT SP2.

[0090]

[0111] In some aspects, the AP 1012 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP1. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1012 to the STAs 1014. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1012 to the STAs 1014. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STAs 1014 may schedule their communications to avoid interfering with latency-sensitive traffic in BSS1 (during r-TWT SP1) based on the cooperative r-TWT signaling information.

[0091]

[0112] 11A shows a sequence diagram 1100 illustrating an example message exchange between BSSs (BSS1 and BSS2) supporting cooperative scheduling of r-TWT SPs according to some implementations. As shown in FIG. 11A, BSS1 includes AP 1101 and STA 1103, and BSS2 includes AP 1102 and STA 1104. In some implementations, each of AP 1101 and 1102 may be an example of AP 711 and 712, respectively, in FIG. 7, STA 1103 may be an example of either STA 701 or 702, and STA 1104 may be an example of any of STAs 703 to 705.

[0092]

[0113] In some aspects, APs 1101 and 1102 may coordinate the scheduling of r-TWT SPs of BSS1 and BSS2 in a distributed manner such that latency-sensitive communications in BSS1 do not interfere or collide with latency-sensitive communications in BSS2. In the example of FIG. 11A, AP 1101 schedules a first r-TWT SP (r-TWT SP1) for BSS1 and communicates coordinated r-TWT signaling information indicating the schedule for r-TWT SP1 to AP 1102. In some implementations, AP 1101 may communicate the coordinated r-TWT signaling information to AP 1102 via a backhaul (wired or wireless). In some other implementations, AP 1101 may transmit the coordinated r-TWT signaling information to AP 1102 via one or more wireless communication packets or frames (such as a new action frame or an enhanced broadcast service (EBCS) frame).

[0093]

[0114] The AP 1102 schedules a second r-TWT SP (r-TWT SP2) for BSS2 based on the received coordinated r-TWT signaling information. More specifically, the AP 1102 may coordinate its schedule for r-TWT SP2 based on the schedule for r-TWT SP1. In some implementations, the AP 1102 may schedule the r-TWT SP2 to be orthogonal in time with the r-TWT SP1 (as described with reference to FIG. 8). In some other implementations, the AP 1102 may schedule the r-TWT SP2 to overlap in time with the r-TWT SP1 (as described with reference to FIG. 9). In such implementations, the access points AP 1101 and 1102 may further coordinate the allocation of resources (such as transmit power, timing, or frequency allocation) for wireless communication during the overlapping service periods r-TWT SP1 and r-TWT SP2.

[0094]

[0115] In some implementations, the AP 1102 may negotiate with the AP 1101 to schedule the r-TWT SP2 based on the coordinated r-TWT signaling information received from the AP 1101. For example, the AP 1102 may determine that the intended schedule for the r-TWT SP1 cannot allow a suitable schedule to be allocated to the r-TWT SP2. Thus, the AP 1102 may reject one or more aspects of the intended schedule for the r-TWT SP1 (such as the intended transmit power or resource allocation). Similarly, the AP 1101 may negotiate with the AP 1102 to schedule the r-TWT SP1. As a result of the negotiation process, the APs 1101 and 1102 may coordinate their schedules for the r-TWT SP1 and r-TWT SP2, respectively, in a manner suitable for latency-sensitive traffic in the BSS1 and BSS2.

[0095]

[0116] The AP 1101 further transmits or broadcasts r-TWT schedule information indicating a schedule for the r-TWT SP1. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1101 to the STA 1103 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1101, the STA 1103 joins (as a member) the r-TWT SP1. In some implementations, the r-TWT schedule information may assign the STA 1103 to the r-TWT SP1. In some other implementations, the STA 1103 may request to join the r-TWT SP1 based on the received r-TWT schedule information. The AP 1101 and the STA 1103 may then exchange latency-sensitive traffic during the r-TWT SP1.

[0096]

[0117] In some aspects, the AP 1101 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP2. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1101 to the STAs 1103. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1101 to the STAs 1103. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STAs 1103 may schedule their communications based on the cooperative r-TWT signaling information to avoid interfering with latency-sensitive traffic in BSS2 (during r-TWT SP2).

[0097]

[0118] The AP 1102 further transmits or broadcasts r-TWT schedule information indicating a schedule for the r-TWT SP2. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1102 to the STAs 1104 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1102, the STAs 1104 join (as members) the r-TWT SP2. In some implementations, the r-TWT schedule information may assign the STA 1104 to the r-TWT SP2. In some other implementations, the STAs 1104 may request to join the r-TWT SP2 based on the received r-TWT schedule information. The AP 1102 and the STAs 1104 may then exchange latency-sensitive traffic during the r-TWT SP2.

[0098]

[0119] In some aspects, the AP 1102 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP1. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1102 to the STAs 1104. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1102 to the STAs 1104. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STAs 1104 may schedule their communications to avoid interfering with latency-sensitive traffic in BSS1 (during r-TWT SP1) based on the cooperative r-TWT signaling information.

[0099]

[0120] 11B shows a sequence diagram 1110 illustrating an example message exchange between BSSs (BSS1 and BSS2) supporting cooperative scheduling of r-TWT SPs according to some implementations. As shown in FIG. 11B, BSS1 includes AP 1111 and STA 1113, and BSS2 includes AP 1112 and STA 1114. In some implementations, each of AP 1111 and 1112 may be an example of AP 711 and 712, respectively, of FIG. 7, STA 1113 may be an example of either STA 701 or 702, and STA 1114 may be an example of any of STAs 703 to 705.

[0100]

[0121] In some aspects, APs 1111 and 1112 may coordinate the scheduling of r-TWT SPs for BSS1 and BSS2 in a distributed manner such that latency-sensitive communications in BSS1 do not interfere or collide with latency-sensitive communications in BSS2. In the example of FIG. 11B, AP 1111 schedules a first r-TWT SP (r-TWT SP1) for BSS1 and transmits or broadcasts r-TWT schedule information indicating the schedule for r-TWT SP1. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by AP 1111 to STA 1113 (such as in accordance with existing versions of the IEEE 802.11 standard). STA 1113 joins (as a member) r-TWT SP1 in response to receiving the r-TWT schedule information from AP 1111. In some implementations, the r-TWT schedule information may assign the STA 1113 to r-TWT SP1. In some other implementations, the STA 1113 may request to join the r-TWT SP1 based on the received r-TWT schedule information. The AP 1111 and the STA 1113 may then exchange latency-sensitive traffic during the r-TWT SP1.

[0101]

[0122] The AP 1112 obtains r-TWT schedule information from the AP 1111 and schedules a second r-TWT SP (r-TWT SP2) for BSS2 based on the obtained r-TWT schedule information. For example, the AP 1112 may obtain the r-TWT schedule information by eavesdropping on one or more frames transmitted by the AP 1111 to the STA 1113 (or other STAs in BSS1). As a result, the AP 1112 may coordinate its schedule for the r-TWT SP2 based on the schedule for the r-TWT SP1. In some implementations, the AP 1112 may schedule the r-TWT SP2 to be orthogonal in time with the r-TWT SP1 (as described with reference to FIG. 8). In some other implementations, the AP 1112 may schedule the r-TWT SP2 to be overlapped in time with the r-TWT SP1 (as described with reference to FIG. 9). In such an implementation, the access points AP1111 and 1112 may further coordinate the allocation of resources (such as transmit power, timing, or frequency allocations) for wireless communication during the overlapping service periods r-TWT SP1 and r-TWT SP2.

[0102]

[0123] The AP 1112 further transmits or broadcasts r-TWT schedule information indicating a schedule for the r-TWT SP2. For example, the r-TWT schedule information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1112 to the STAs 1114 (such as in accordance with existing versions of the IEEE 802.11 standard). In response to receiving the r-TWT schedule information from the AP 1112, the STAs 1114 join (as members) the r-TWT SP2. In some implementations, the r-TWT schedule information may assign the STA 1114 to the r-TWT SP2. In some other implementations, the STAs 1114 may request to join the r-TWT SP2 based on the received r-TWT schedule information. The AP 1112 and the STAs 1114 may then exchange latency-sensitive traffic during the r-TWT SP2.

[0103]

[0124] In some aspects, the AP 1112 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP1. In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1112 to the STAs 1114. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1112 to the STAs 1114. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, the STAs 1114 may schedule their communications to avoid interfering with latency-sensitive traffic in BSS1 (during r-TWT SP1) based on the cooperative r-TWT signaling information.

[0104]

[0125] In some aspects, the AP 1111 may also transmit cooperative r-TWT signaling information indicating a schedule for r-TWT SP2. For example, the AP 1111 may obtain the schedule for r-TWT SP2 by eavesdropping on one or more frames transmitted by the AP 1112 to the STA 1114 (or other STAs in BSS2). In some implementations, the cooperative r-TWT signaling information may be carried in a broadcast r-TWT IE included in a beacon frame or other management frame transmitted by the AP 1111 to the STA 1113. In some other implementations, the cooperative r-TWT signaling information may be carried in a new cooperative r-TWT IE in a beacon frame or other management frame transmitted by the AP 1111 to the STA 1113. Still further, in some implementations, the cooperative r-TWT signaling information may be carried in a new frame or packet (such as an MPDU or PPDU) designed for cooperative r-TWT signaling. As a result, STA 1113 may schedule its communications based on the cooperative r-TWT signaling information to avoid interfering with latency-sensitive traffic in BSS2 (during r-TWT SP2).

[0105]

[0126] FIG. 12 illustrates an exemplary packet 1200 that can be used for cooperative r-TWT signaling between one or more APs and one or more STAs, according to some implementations. In the example of FIG. 12, the packet 1200 is illustrated as an MPDU frame. For example, referring to FIG. 3, the packet 1200 can be an example of an MPDU frame 310. In some implementations, the packet 1200 can be a management frame type (such as a beacon or probe response frame) defined in existing versions of the IEEE 802.11 standard. In some other implementations, the packet 1200 can be a new type of frame (such as an action frame or an EBCS frame) designed for cooperative r-TWT signaling.

[0106]

[0127] In some aspects, the packet 1200 may be transmitted by an AP to one or more STAs associated with its BSS. In some implementations, the packet 1200 may be used to assign STAs associated with one or more r-TWT SPs to be allocated to latency-sensitive communications in the current BSS. In some other implementations, the packet 1200 may be used to prevent the associated STAs from interfering with latency-sensitive communications in one or more OBSSs. In some other aspects, the packet 1200 may be transmitted by an AP to other APs associated with one or more OBSSs. In some implementations, the packet 1200 may be used to coordinate r-TWT SP schedules with other APs. In some other implementations, the packet 1200 may be used to prevent other APs from interfering with latency-sensitive communications in the current BSS.

[0107]

[0128] The packet 1200 includes a MAC header 1210 followed by a frame body 1220 and an FCS 1230. Although not shown for simplicity, the MAC header 1210 may include a frame control field, a duration field, a receiver address (RA) field, and a transmitter address (TA) field. The frame body 1220 includes one or more IEs that carry information regarding r-TWT operation. In some implementations, the frame body 1220 may include a broadcast TWT element 1221 and a quiet element 1222. The broadcast TWT element 1221 includes several (N) restricted TWT parameter sets 1231(1)-1231(N), each carrying information associated with a respective r-TWT SP. In some implementations, at least one of the restricted TWT parameter sets 1231(1)-1231(N) is used to carry r-TWT schedule information 1224, and at least one of the restricted TWT parameter sets 1231(1)-1231(N) is used to carry coordinated r-TWT signaling information 1225.

[0108]

[0129] In some implementations, the r-TWT schedule information 1224 may be an example of any of the r-TWT schedule information described with reference to Figures 7-11B. More specifically, the r-TWT schedule information 1224 may indicate an r-TWT SP schedule for the current BSS. In some implementations, the cooperative r-TWT signaling information 1225 may be an example of any of the cooperative r-TWT signaling information described with reference to Figures 7-11B. More specifically, the cooperative r-TWT signaling information 1225 may indicate an r-TWT SP schedule for the OBSS. The quiet element 1222 may carry information indicating one or more quiet durations (as defined in existing versions of the IEEE 802.11 standard). In some implementations, the one or more quiet durations may span the duration of one or more r-TWT SPs allocated to the current BSS. In some other implementations, the quiet duration or durations may span the duration of one or more r-TWT SPs allocated to the OBSS.

[0109]

[0130] In some implementations, the broadcast TWT element 1221 may conform to an existing broadcast TWT element format as defined in the IEEE 802.11be amendment to the IEEE 802.11 standard. In such implementations, the cooperative r-TWT signaling information 1225 may be implemented with only minor modifications to the IEEE 802.11 standard. However, aspects of the present disclosure recognize that each restricted TWT parameter set may include information that is unrelated or unnecessary for cooperative r-TWT signaling (such as information used to set up or establish an r-TWT SP with one or more low latency STAs). Thus, in some implementations, the cooperative r-TWT signaling information 1225 may represent only a subset of the information conveyed in the restricted TWT parameter set.

[0110]

[0131] FIG. 13 illustrates another exemplary packet 1300 that can be used for cooperative r-TWT signaling between one or more APs and one or more STAs, according to some implementations. In the example of FIG. 13, the packet 1300 is illustrated as an MPDU frame. For example, referring to FIG. 3, the packet 1300 can be an example of an MPDU frame 310. In some implementations, the packet 1300 can be a management frame type (such as a beacon or probe response frame) defined in existing versions of the IEEE 802.11 standard. In some other implementations, the packet 1300 can be a new type of frame (such as an action frame or an EBCS frame) designed for cooperative r-TWT signaling.

[0111]

[0132] In some aspects, the packet 1300 may be transmitted by an AP to one or more STAs associated with its BSS. In some implementations, the packet 1300 may be used to assign STAs associated with one or more r-TWT SPs to be allocated to latency-sensitive communications in the current BSS. In some other implementations, the packet 1300 may be used to prevent the associated STAs from interfering with latency-sensitive communications in one or more OBSSs. In some other aspects, the packet 1300 may be transmitted by an AP to other APs associated with one or more OBSSs. In some implementations, the packet 1300 may be used to coordinate r-TWT SP schedules with other APs. In some other implementations, the packet 1300 may be used to prevent other APs from interfering with latency-sensitive communications in the current BSS.

[0112]

[0133] The packet 1300 includes a MAC header 1310 followed by a frame body 1320 and an FCS 1330. Although not shown for simplicity, the MAC header 1310 may include a frame control field, a duration field, an RA field, and a TA field. The frame body 1320 includes one or more IEs that carry information regarding r-TWT operation. In some implementations, the frame body 1320 may include a broadcast TWT element 1321, a quiet element 1322, and a cooperative r-TWT element 1323. In the example of FIG. 13, the broadcast TWT element 1321 carries r-TWT schedule information 1324, and the cooperative r-TWT element 1323 carries cooperative r-TWT signaling information 1325.

[0113]

[0134] In some implementations, the r-TWT schedule information 1324 may be an example of any of the r-TWT schedule information described with reference to Figures 7-11B. More specifically, the r-TWT schedule information 1324 may indicate an r-TWT SP schedule for the current BSS. In some implementations, the cooperative r-TWT signaling information 1325 may be an example of any of the cooperative r-TWT signaling information described with reference to Figures 7-11B. More specifically, the cooperative r-TWT signaling information 1325 may indicate an r-TWT SP schedule for the OBSS. The quiet element 1322 may carry information indicating one or more quiet durations (as defined in existing versions of the IEEE 802.11 standard). In some implementations, the one or more quiet durations may span the duration of one or more r-TWT SPs allocated to the current BSS. In some other implementations, the quiet duration or durations may span the duration of one or more r-TWT SPs allocated to the OBSS.

[0114]

[0135] For simplicity, only one coordinated r-TWT element 1323 is shown in FIG. 13, but in some other implementations, the packet 1300 may include any number (N) of coordinated r-TWT elements to carry coordinated r-TWT signaling information for N OBSSs, respectively. In some implementations, the coordinated r-TWT signaling information 1325 may include only a set of parameters required for coordinated r-TWT signaling (or scheduling). For example, referring to FIG. 12, the coordinated r-TWT signaling information 1325 may include only a subset of information carried in the restricted TWT parameter set 1223(N). In some implementations, the coordinated r-TWT signaling information 1325 may include one or more additional parameters not included in the restricted TWT parameter set 1223(N). For example, the additional parameters may represent information specific to coordinated r-TWT signaling.

[0115]

[0136] As shown in FIG. 13, the cooperative r-TWT signaling information 1325 may include TWT information indicating the time (relative to the TBTT) that a low latency STA associated with an r-TWT SP must be awake, i.e., a nominal minimum TWT wake duration indicating the duration of an r-TWT SP (in wake duration units), a TWT wake interval indicating the average time between r-TWT SPs (which may be calculated using the TWT wake interval mantissa and the TWT wake interval exponent), wake duration units (μs or TU), a broadcast TWT ID used to identify the r-TWT SP, and broadcast TWT persistence information indicating the duration (in TBTT) for which the cooperative r-TWT signaling information 1325 is valid.

[0116]

[0137] In some implementations, the cooperative r-TWT signaling information 1325 may include trigger information indicating whether the latency-sensitive communication during the r-TWT SP is trigger-based, non-trigger-based, or a hybrid thereof, i.e., a TID bitmap indicating one or more traffic identifiers (TIDs) supported by the r-TWT SP, a link ID bitmap indicating one or more communication links that may be used to communicate latency-sensitive data traffic during the r-TWT SP, an indication of the number of member STAs assigned (or subscribed) to the r-TWT SP, a sharing bit indicating whether the r-TWT SP may be shared by overlapping r-TWT SPs (e.g., multi-AP cooperation opportunities), an indication of whether the r-TWT SP is allocated for peer-to-peer (P2P) communication, infrastructure BSS (infrastructure) communication, or a hybrid thereof, SP type information indicating whether the cooperative r-TWT signaling information 1325 is associated with a current BSS or an OBSS ... It may further include SP status information indicating whether membership in the SP is full or not, TBTT information that may be used to coordinate TBTT timing or frequency among multiple APs, maximum TXOP duration information indicating the maximum duration that may be allocated to a TXOP during an r-TWT SP, and an indication of one or more EDCA parameters supported by the r-TWT SP.

[0117]

[0138] In some aspects, parameters associated with the cooperative r-TWT signaling information 1325 may vary depending on whether the intended recipient of the packet 1300 is a STA (associated with the current BSS) or an AP (associated with the OBSS). For example, one or more parameters (such as a shared bit or TBTT information) may be omitted from the cooperative r-TWT signaling information 1325 provided to STAs in the current BSS to reduce signaling overhead for the packet 1300. Similarly, one or more parameters (such as a TID bitmap or SP status information) may be omitted from the cooperative r-TWT signaling information 1325 provided to APs in one or more OBSSs.

[0118]

[0139] 14 shows a flowchart illustrating an example process 1400 of wireless communication supporting coordinated scheduling and signaling of r-TWT SPs. In some implementations, the process 1400 may be performed by a wireless communication device operating as or within an AP, such as one of the APs 102 or 502, described above with reference to FIG. 1 and FIG. 5A, respectively.

[0119]

[0140] In some implementations, process 1400 begins at block 1402 with receiving cooperative r-TWT signaling information associated with a first r-TWT SP associated with the BSS associated with the wireless communication device. At block 1404, process 1400 proceeds to transmit r-TWT schedule information indicating a second r-TWT SP associated with the BSS associated with the wireless communication device based on the cooperative r-TWT signaling information. At block 1406, process 1400 proceeds to communicate with one or more first STAs during the second r-TWT SP based on respective latency requirements of each of the one or more first STAs.

[0120]

[0141] In some aspects, the first r-TWT SP may be orthogonal in time with the second r-TWT SP. In some other aspects, the first r-TWT may overlap in time with the second r-TWT SP. In some implementations, the wireless communication device may communicate with one or more first STAs by transmitting a MU-RTS frame to the one or more first STAs. In some other implementations, the coordinated r-TWT signaling information may include shared SP information indicating a multi-AP coordination opportunity associated with the first r-TWT SP. In such implementations, the wireless communication device may coordinate with an AP associated with the OBSS based on the shared SP information such that communication with the one or more first STAs occurs simultaneously with communication in the OBSS.

[0121]

[0142] In some implementations, the wireless communication devices may coordinate with the AP by exchanging transmit power information indicating at least one of a transmit power associated with communication with one or more first STAs or a transmit power associated with communication in an OBSS. In some other implementations, the wireless communication devices may coordinate with the AP by exchanging frequency resource information indicating at least one of an allocation of frequency resources for communication with one or more first STAs or an allocation of frequency resources for communication in an OBSS.

[0122]

[0143] In some aspects, the cooperative r-TWT signaling information may indicate an allocation of resources for the second r-TWT SP. In some other aspects, the cooperative r-TWT signaling information may indicate an allocation of resources for the first r-TWT SP. In some implementations, the wireless communication device may negotiate an allocation of resources for the second r-TWT SP with an AP associated with the OBSS based on the cooperative r-TWT signaling information. In some implementations, the cooperative r-TWT signaling information may be carried in one or more packets transmitted by an AP associated with the OBSS to the wireless communication device. In some other implementations, the cooperative r-TWT signaling information may be carried in one or more management frames transmitted by an AP associated with the OBSS to one or more STAs associated with the OBSS. In some implementations, the cooperative r-TWT signaling information may be received from a STA associated with a BSS that overhears one or more management frames transmitted by an AP associated with the OBSS.

[0123]

[0144] In some aspects, the wireless communication device may further transmit r-TWT coordination information indicating a first r-TWT SP associated with the OBSS. In some implementations, the r-TWT schedule information and the r-TWT coordination information may be carried in a broadcast TWT IE included in one or more packets transmitted by the wireless communication device. In some other implementations, the r-TWT schedule information and the r-TWT coordination information may be carried in a broadcast TWT IE and a coordinated r-TWT IE, respectively, included in one or more packets transmitted by the wireless communication device, where the coordinated r-TWT IE is different from the broadcast TWT IE.

[0124]

[0145] 15A shows a flowchart illustrating an example process 1500 of wireless communication supporting coordinated scheduling and signaling of r-TWT SPs. In some implementations, the process 1500 may be performed by a wireless communication device operating as or within an AP, such as one of the APs 102 or 502, described above with reference to FIGS. 1 and 5A, respectively.

[0125]

[0146] In some implementations, process 1500 begins with transmitting first coordinated r-TWT signaling information indicating a first r-TWT SP associated with a first BSS at block 1502. At block 1504, process 1500 proceeds to transmitting second coordinated r-TWT signaling information indicating a second r-TWT SP associated with a second BSS based on the first r-TWT SP. In some aspects, the first r-TWT SP may be orthogonal in time to the second r-TWT SP.

[0126]

[0147] In some other aspects, the first r-TWT SP may overlap in time with the second r-TWT SP. In some implementations, the first coordinated r-TWT signaling information may indicate a transmit power associated with a communication in a first BSS during the first r-TWT SP, and the second coordinated r-TWT signaling information may indicate a transmit power associated with a communication in a second BSS during the second r-TWT SP. In some other implementations, the first coordinated r-TWT signaling information may indicate an allocation of a first frequency resource for a communication in a first BSS during the first r-TWT SP, and the second coordinated r-TWT signaling information may indicate an allocation of a second frequency resource for a communication in a second BSS during the second r-TWT SP. In such implementations, the first frequency resource may be orthogonal to the second frequency resource.

[0127]

[0148] In some implementations, the first and second cooperative r-TWT signaling information may be carried in a broadcast TWT IE included in one or more packets transmitted by the wireless communication device. In some other implementations, the first and second cooperative r-TWT signaling information may be carried in first and second cooperative r-TWT IEs, respectively, included in one or more packets transmitted by the wireless communication device.

[0128]

[0149] 15B shows a flowchart illustrating an example process 1510 of wireless communication supporting coordinated scheduling and signaling of r-TWT SPs. In some implementations, the process 1510 may be performed by a wireless communication device operating as or within an AP, such as one of the APs 102 or 502, described above with reference to FIGS. 1 and 5A, respectively.

[0129]

[0150] 15A, process 1510 may begin at block 1512 after transmitting the first cooperative r-TWT signaling information at block 1502 and after transmitting the second cooperative r-TWT signaling information at block 1504. In some implementations, process 1510 begins at block 1512 with transmitting r-TWT schedule information indicating a third r-TWT SP associated with a third BSS associated with the wireless communication device based on the first r-TWT SP and the second r-TWT SP. At block 1514, process 1510 proceeds to communicate with one or more STAs during the third r-TWT SP based on respective latency requirements of each of the one or more STAs.

[0130]

[0151] Figure 16 shows a block diagram of an example wireless communication device 1600 according to some implementations. In some implementations, the wireless communication device 1600 is configured to perform the process 1400 described above with reference to Figure 14. The wireless communication device 1600 may be an example implementation of the wireless communication device 400 described above with reference to Figure 4. For example, the wireless communication device 1600 may be a chip, SoC, chipset, package, or device including at least one processor and at least one modem (e.g., a Wi-Fi (IEEE 802.11) modem or a cellular modem).

[0131]

[0152] The wireless communication device 1600 includes a receiving component 1610, a communications manager 1620, and a transmitting component 1630. The communications manager 1620 further includes an r-TWT coordination component 1622, an r-TWT scheduling component 1624, and an r-TWT communication component 1626. One or more portions of the components 1622, 1624, and 1626 may be implemented at least in part in hardware or firmware. In some implementations, at least some of the components 1622, 1624, or 1626 are implemented at least in part as software stored in a memory (such as memory 408). For example, one or more portions of the components 1622, 1624, and 1626 may be implemented as non-transitory instructions (or “code”) executable by a processor (such as processor 406) to perform the functions or operations of the respective components.

[0132]

[0153] The receiving component 1610 is configured to receive RX signals from one or more other wireless communication devices over a wireless channel. The transmitting component 1630 is configured to transmit TX signals to one or more other wireless communication devices over a wireless channel. The communications manager 1620 is configured to control or manage communications with one or more other wireless communication devices. In some implementations, the r-TWT adjustment component 1622 may receive cooperative r-TWT signaling information associated with a first r-TWT SP associated with the OBSS, the r-TWT scheduling component 1624 may transmit r-TWT schedule information indicating a second r-TWT SP associated with a BSS associated with the wireless communication device based on the cooperative r-TWT signaling information, and the r-TWT communication component 1626 may communicate with one or more STAs during the second r-TWT SP based on a respective latency requirement of each of the one or more STAs.

[0133]

[0154] FIG. 17 shows a block diagram of an example wireless communication device 1700 according to some implementations. In some implementations, the wireless communication device 1700 is configured to perform the process 1500 described above with reference to FIG. 15. The wireless communication device 1700 may be an example implementation of the wireless communication device 400 described above with reference to FIG. 4. For example, the wireless communication device 1700 may be a chip, SoC, chipset, package, or device including at least one processor and at least one modem (e.g., a Wi-Fi (IEEE 802.11) modem or a cellular modem).

[0134]

[0155] The wireless communication device 1700 includes a receiving component 1710, a communications manager 1720, and a transmitting component 1730. The communications manager 1720 further includes a cooperative r-TWT scheduling component 1722. Portions of the cooperative r-TWT scheduling component 1722 may be implemented at least in part in hardware or firmware. In some implementations, the cooperative r-TWT scheduling component 1722 is implemented at least in part as software stored in a memory (such as the memory 408). For example, portions of the cooperative r-TWT scheduling component 1722 may be implemented as non-transitory instructions (or “code”) executable by a processor (such as the processor 406) to perform the functions or operations of the respective components.

[0135]

[0156] The receiving component 1710 is configured to receive RX signals from one or more other wireless communication devices over a wireless channel. The transmitting component 1730 is configured to transmit TX signals to one or more other wireless communication devices over a wireless channel. The communications manager 1720 is configured to control or manage communications with one or more other wireless communication devices. In some implementations, the cooperative r-TWT scheduling component 1722 may transmit first cooperative r-TWT signaling information indicating a first r-TWT SP associated with a first BSS and may further transmit second cooperative r-TWT signaling information indicating a second r-TWT SP associated with a second BSS based on the first r-TWT SP.

[0136]

[0157] The following numbered clauses describe example implementations.

[0137] Clause 1. A method of wireless communication by a wireless communication device, comprising: receiving cooperative restricted target wake time (r-TWT) signaling information associated with a first r-TWT service period (SP) associated with an overlapping basic service set (OBSS); transmitting r-TWT schedule information indicating a second r-TWT SP associated with a basic service set (BSS) associated with the wireless communication device based on the cooperative r-TWT signaling information; and communicating with one or more first wireless stations (STAs) during a second r-TWT SP based on a respective latency requirement of each of the one or more first STAs.

[0138] Clause 2. The method of clause 1, wherein the first r-TWT SP is orthogonal in time to the second r-TWT SP.

[0139] Clause 3. The method of clause 1, wherein the first r-TWT overlaps in time with the second r-TWT SP.

[0140] Clause 4: Communicating with one or more first STAs 4. The method of any one of clauses 1 or 3, comprising transmitting a multi-user request to send (MU-RTS) frame to one or more first STAs.

[0141] Clause 5. The method of any one of clauses 1 or 3, wherein the cooperative r-TWT signaling information includes shared SP information indicating a multiple access point (multi-AP) cooperation opportunity associated with a first r-TWT SP.

[0142] Clause 6. Communicating with one or more first STAs The method of any one of clauses 1, 3 or 5, comprising coordinating with an access point (AP) associated with an OBSS based on shared SP information so that communication with one or more first STAs occurs simultaneously with communication in the OBSS.

[0143] Article 7 Cooperation with AP The method of any one of clauses 1, 3, 5 or 6, comprising exchanging transmission power information with an AP indicating at least one of a transmission power associated with communication with one or more first STAs or a transmission power associated with communication in an OBSS.

[0144] Article 8 Cooperation with AP 7. The method of any one of clauses 1, 3, 5 or 6, comprising exchanging frequency resource information with an AP indicating at least one of an allocation of frequency resources for communication with one or more first STAs or an allocation of frequency resources for communication in an OBSS.

[0145] Clause 9. The method of any one of clauses 1 to 8, wherein the cooperative r-TWT signaling information indicates an allocation of resources for a second r-TWT SP.

[0146] Clause 10. The method of any one of clauses 1 to 8, wherein the cooperative r-TWT signaling information indicates an allocation of resources for a first r-TWT SP.

[0147] Clause 11 further includes negotiating with an AP associated with the OBSS an allocation of resources for the second r-TWT SP based on the cooperative r-TWT signaling information. 11. The method according to any one of clauses 1 to 8 or 10.

[0148] Clause 12. The method of any one of clauses 1 to 8 or 10, wherein the cooperative r-TWT signaling information is carried in one or more packets transmitted to the wireless communication device by an AP associated with the OBSS.

[0149] Clause 13. The method of any one of clauses 1 to 8 or 10, wherein the cooperative r-TWT signaling information is carried in one or more management frames transmitted by an AP associated with the OBSS to one or more STAs associated with the OBSS.

[0150] Clause 14. The method of any one of clauses 1 to 8 or 10, wherein the cooperative r-TWT signaling information is received from a STA associated with a BSS that intercepts one or more management frames transmitted by an AP associated with the BSS.

[0151] Clause 15 further comprising transmitting r-TWT cooperation information indicating a first r-TWT SP associated with the OBSS. 15. The method according to any one of clauses 1 to 14.

[0152] Clause 16. The method of any one of clauses 1 to 15, wherein the r-TWT schedule information and the r-TWT coordination information are carried in a broadcast target wake time (TWT) information element (IE) included in one or more packets transmitted by the wireless communication device.

[0153] Clause 17. The method of any one of clauses 1 to 15, wherein the r-TWT schedule information and the r-TWT coordination information are respectively carried in a broadcast TWT IE and a coordinated r-TWT IE included in one or more packets transmitted by the wireless communication device, and the coordinated r-TWT IE is different from the broadcast TWT IE.

[0154] Clause 18 At least one processor; at least one memory communicatively coupled to the at least one processor, the memory storing processor readable code configured, when executed by the at least one processor, to perform a method according to any one or more of clauses 1 to 17; Wireless communication devices.

[0155] Clause 19. A method of wireless communication performed by a wireless communication device, comprising: transmitting first cooperative restricted target wake time (r-TWT) signaling information indicating a first r-TWT service period (SP) associated with a first basic service set (BSS); and transmitting, based on the first r-TWT SP, second coordinated r-TWT signaling information indicating a second r-TWT SP associated with a second BSS.

[0156] Clause 20. The method of clause 19, wherein the first r-TWT SP is orthogonal in time to the second r-TWT SP.

[0157] Clause 21. The method of clause 19, wherein a first r-TWT SP overlaps in time with a second r-TWT SP.

[0158] Clause 22. The method of any one of clauses 19 or 21, wherein the first coordinated r-TWT signaling information indicates a transmit power associated with a communication in a first BSS in a first r-TWT SP, and the second coordinated r-TWT signaling information indicates a transmit power associated with a communication in a second BSS in a second r-TWT SP.

[0159] Clause 23. The method of any one of clauses 19, 21, or 22, wherein the first coordinated r-TWT signaling information indicates an allocation of a first frequency resource for communication in a first BSS in a first r-TWT SP, and the second coordinated r-TWT signaling information indicates an allocation of a second frequency resource for communication in a second BSS in a second r-TWT SP.

[0160] Clause 24. The method of any one of clauses 19 or 21 to 23, wherein the first frequency resource is orthogonal to the second frequency resource.

[0161] Clause 25. The method of any one of clauses 19 to 24, wherein the first cooperative r-TWT signaling information and the second cooperative r-TWT signaling information are carried in a broadcast target wake time (TWT) information element (IE) included in one or more packets transmitted by the wireless communication device.

[0162] Clause 26. The method of any one of clauses 19 to 24, wherein the first cooperative r-TWT signaling information and the second cooperative r-TWT signaling information are carried in first and second cooperative r-TWT IEs, respectively, included in one or more packets transmitted by the wireless communication device.

[0163] Clause 27 transmitting r-TWT schedule information indicating a third r-TWT SP associated with a third BSS associated with the wireless communication device based on the first r-TWT SP and the second r-TWT SP; and communicating with one or more wireless stations (STAs) during the third r-TWT SP based on a respective latency requirement of each of the one or more STAs. 27. The method according to any one of clauses 19 to 26.

[0164] Clause 28 At least one processor; at least one memory communicatively coupled to the at least one processor, the memory storing processor readable code configured, when executed by the at least one processor, to perform a method according to any one or more of clauses 19 to 27; Wireless communication devices.

[0165]

[0158] As used herein, phrases referring to "at least one of" or "one or more of" a list of items refer to any combination of those items, including single elements. For example, "at least one of a, b, or c" is intended to encompass the possibilities of a only, b only, c only, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a, b, and c.

[0166]

[0159] The various exemplary components, logic, logic blocks, modules, circuits, operations, and algorithmic processes described with respect to the implementations disclosed herein may be implemented as electronic hardware, firmware, software, or a combination of hardware, firmware, or software, including the structures disclosed herein and their structural equivalents. The compatibility of hardware, firmware, and software is generally described in terms of functionality and is shown in the various exemplary components, blocks, modules, circuits, and processes described above. Whether such functionality is implemented in hardware, firmware, or software depends on the specific application and design constraints imposed on the overall system.

[0167]

[0160] Various modifications of the implementations described in this disclosure may be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other implementations without departing from the spirit or scope of this disclosure. Thus, the claims are not limited to the implementations shown in this specification, but should be accorded the widest scope consistent with this disclosure, the principles and novel features disclosed herein.

[0168]

[0161] In addition, various features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Thus, although features are described above as working in a particular combination and may even be initially claimed as such, in some cases, one or more features from the claimed combination can be deleted from the combination, and the claimed combination may be directed to a subcombination or a variation of the subcombination.

[0169]

[0162] Similarly, although operations are illustrated in the drawings in a particular order, this should not be understood as requiring such operations to be performed in the particular order or sequential order shown, or all of the operations shown to achieve a desired result. Furthermore, the drawings may generally illustrate another exemplary process in the form of a flow chart or flow diagram. However, other operations not shown may be incorporated into the exemplary process generally illustrated. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the illustrated operations. In some circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the program components and systems described may generally be integrated together in a single software product or packaged in multiple software products.

Claims

1. A method for wireless communication by a wireless communication device operating as or within an access point (AP), comprising: receiving cooperative r-TWT signaling information associated with a first restricted target wake time (r-TWT) service period (SP) associated with an overlapping basic service set (OBSS); transmitting r-TWT schedule information indicating a second r-TWT SP associated with a basic service set (BSS) associated with the wireless communication device based on the cooperative r-TWT signaling information; and communicating with one or more first wireless stations (STAs) during the second r-TWT SP based on a respective latency requirement of each of the one or more first STAs.

2. The method of claim 1 , wherein the first r-TWT SP is orthogonal in time to the second r-TWT SP.

3. the first r-TWT overlaps in time with the second r-TWT SP; The communicating with the one or more first STAs comprises: transmitting a multi-user request to send (MU-RTS) frame to the one or more first STAs; the cooperative r-TWT signaling information includes shared SP information indicating a multiple access point (multi-AP) cooperation opportunity associated with the first r-TWT SP; The communicating with the one or more first STAs comprises: coordinating with an access point (AP) associated with the OBSS based on the shared SP information so that the communication with the one or more first STAs occurs simultaneously with communication in the OBSS; The coordinating with the AP comprises: exchanging transmit power information with the AP indicating at least one of a transmit power associated with the communication with the one or more first STAs or a transmit power associated with the communication in the OBSS; or The coordinating with the AP comprises:

2. The method of claim 1, comprising exchanging frequency resource information with the AP indicating at least one of an allocation of frequency resources for the communication with the one or more first STAs or an allocation of frequency resources for the communication in the OBSS.

4. The method of claim 1 , wherein the cooperative r-TWT signaling information indicates allocation of resources for the second r-TWT SP.

5. The method of claim 1 , wherein the cooperative r-TWT signaling information indicates allocation of resources for the first r-TWT SP.

6. and negotiating, based on the cooperative r-TWT signaling information, an allocation of resources for the second r-TWT SP with an AP associated with the OBSS. The method of claim 5.

7. 6. The method of claim 5, wherein the cooperative r-TWT signaling information is carried in one or more packets transmitted to the wireless communication device by an AP associated with the OBSS.

8. the cooperative r-TWT signaling information is carried in one or more management frames transmitted by an AP associated with the OBSS to one or more STAs associated with the OBSS; The method of claim 5, wherein the cooperative r-TWT signaling information is received from a STA associated with the BSS that overhears the one or more management frames transmitted by the AP associated with the OBSS.

9. transmitting r-TWT coordination information indicating the first r-TWT SP associated with the OBSS; The r-TWT scheduling information and the r-TWT coordination information are carried in a Broadcast Target Wake Time (TWT) information element (IE) included in one or more packets transmitted by the wireless communication device; or the r-TWT schedule information and the r-TWT coordination information are carried in a broadcast TWT IE and a coordinated r-TWT IE, respectively, included in one or more packets transmitted by the wireless communication device, and the coordinated r-TWT IE is different from the broadcast TWT IE; The method of claim 1.

10. A wireless communication device operating as or within an access point (AP), comprising: at least one processor; at least one memory communicatively coupled to the at least one processor and storing processor-readable code; The processor-readable code, when executed by the at least one processor, receiving cooperative restricted target wake time (r-TWT) signaling information associated with a first r-TWT service period (SP) associated with an overlapping basic service set (OBSS); transmitting r-TWT schedule information indicating a second r-TWT SP associated with a basic service set (BSS) associated with the wireless communication device based on the cooperative r-TWT signaling information; and a wireless communication device configured to communicate with one or more first wireless stations (STAs) during the second r-TWT SP based on a respective latency requirement of each of the one or more first STAs.

11. A method for wireless communication by a wireless communication device operating as or within an access point (AP), comprising: Transmitting first cooperative restricted target wake time (r-TWT) signaling information indicating a first r-TWT service period (SP) associated with a first basic service set (BSS); and transmitting second cooperative r-TWT signaling information indicating a second r-TWT SP associated with a second BSS based on the first r-TWT SP.

12. The method of claim 11 , wherein the first r-TWT SP is orthogonal in time to the second r-TWT SP.

13. the first r-TWT SP overlaps in time with the second r-TWT SP; The first cooperative r-TWT signaling information indicates a transmit power associated with a communication in the first BSS during the first r-TWT SP, and the second cooperative r-TWT signaling information indicates a transmit power associated with a communication in the second BSS during the second r-TWT SP; or the first cooperative r-TWT signaling information indicates allocation of a first frequency resource for communication in the first BSS during the first r-TWT SP, and the second cooperative r-TWT signaling information indicates allocation of a second frequency resource for communication in the second BSS during the second r-TWT SP; The method of claim 11 , wherein the first frequency resource is orthogonal to the second frequency resource.

14. A wireless communication device operating as or within an access point (AP), comprising: at least one processor; at least one memory communicatively coupled to the at least one processor and storing processor-readable code; The processor-readable code, when executed by the at least one processor, Transmitting first cooperative restricted target wake time (r-TWT) signaling information indicating a first r-TWT service period (SP) associated with a first basic service set (BSS); and transmitting, based on the first r-TWT SP, second cooperative r-TWT signaling information indicating a second r-TWT SP associated with a second BSS.

15. A computer program comprising instructions: The instructions, when executed by at least one processor of a wireless communication device operating as or within an access point (AP) according to claim 10, cause the at least one processor to perform the method of any one of claims 1 to 9; 15. A computer program product comprising instructions, when executed by at least one processor of a wireless communication device operating as or within an access point (AP) as claimed in claim 14, that cause the at least one processor to perform the method of any one of claims 11 to 13.

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