Methods and mechanisms for enabling multilink mmWave requests and reports

Abstract

A crosslink signaling method and device are described in which a multilink device (MLD) communicates with another device using a first wireless link and a second wireless link. Control and response information for establishing / maintaining the second wireless link is communicated in a signaling field of a frame on the first wireless link, thereby enabling a more reliable control information exchange than over the second wireless link. In one embodiment, the first wireless link is a sub-7 GHz link and the second wireless link is a millimeter wave link. Signaling used to configure parameters of the first wireless link (e.g., a control field, an A-Control subfield of the HT control field, a control frame, a BQR control subfield, an HLA control subfield, a TRS control field, etc.) may be extended to provide associated signaling for another separate link (the second link) between the devices that does not carry signaling information.

Description

[Technical Field]

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 424,010, filed November 9, 2022, the contents of which are incorporated herein by reference. [Background technology]

[0002] A wireless local area network (WLAN) in infrastructure basic service set (BSS) mode has an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or from the BSS. Traffic to a STA originating from outside the BSS arrives through the AP and is delivered to the STA. Traffic originating from a STA to a destination outside the BSS is sent to the AP and delivered to the respective destination. Traffic between STAs within the BSS may be sent through the AP, where the source STA sends traffic to the AP and the AP delivers the traffic to the destination STA.

[0003] Recent efforts have targeted improving WLAN connection reliability, reducing latency, improving manageability, and increasing throughput consumption. Millimeter wave (mmW or mmWave) operation has been proposed as a potential feature that can help achieve one or more of these goals, especially considering the recently defined multi-link operation (MLO) in WLAN standardization efforts.

[0004] mmWave operation can help achieve the above objectives. From one perspective, all devices operating on mmWave bands / links must be MLO-enabled and have at least one active sub-7 GHz link. The discovery and association procedures for this purpose may occur on the lower band / link, and scheduling and broadcasting may be provided on the lower band / link. Beamforming (BF) training using sector sweep (SS) may be performed on the mmWave band / link, but the BF training sequence may be triggered or scheduled from the lower band, and feedback may be provided on the lower band. For widespread adoption and successful communications, various potential options must be addressed. Summary of the Invention

[0005] Embodiments disclosed herein may relate to addressing the aforementioned objectives by providing an extended MAC header capable of conveying mmW link request and response information via a Frame Control field carried within control / management frames transmitted in sub-7 GHz bands. To leverage multi-link operation, embodiments relating to a crosslink signaling mechanism allow a frame transmitted on one link to carry request / response information for another link different from the link used to transmit the frame. In certain embodiments, this crosslink signaling can be achieved by extending the design of an existing Frame Control field. Particular aspects relate to signaling, in a first radio link, extended control frames or extended data / management frames, capabilities, and link establishment information for a second radio link different from the first radio link. Additionally or alternatively, other embodiments relate to crosslink signaling by extending the design of an existing A-Control field in an MLO system.

[0006] According to one aspect, a method and device for a multilink (ML) station (STA) is disclosed that includes transmitting a frame of the ML STA to an ML device over a first wireless link, the frame including a high throughput control (+HTC) field indicating that the frame includes control information for a second wireless link with the ML device and that the second wireless link is different from the first wireless link.

[0007] In one aspect, the control information includes request or response information for establishing or maintaining a second wireless link. In some embodiments, the first wireless link includes a sub-7 GHz link and the second wireless link includes an mmWave link. In other embodiments, the first wireless link includes a 3GPP link and the second wireless link includes an 802.11 link, or vice versa. In some embodiments, the control information includes an A-Control subfield of a high-efficiency (HE) variant high-throughput (HT) control field.

[0008] The ML STA may receive a frame from the ML device over the first wireless link, the received frame including a high throughput (+HTC) field indicating that the received frame includes second control information for the second wireless link. In one embodiment, the second control information includes request or response information for establishing or maintaining the second wireless link. In one embodiment, the second wireless link is established or operated using the second control information received over the first wireless link.

[0009] In some aspects, the control information may be included in an HEHT control field having an extended A-Control subfield. According to another aspect, the control information is present in an extended Bandwidth Query Report (BQR) subfield. In another aspect, the control information is present in an extended High Efficiency Link Adaptation (HLA) control subfield. In another aspect, the control information is present in an extended Trigger Response Scheduling (TRS) control field. In yet another aspect, the control information may include an enhanced transmission opportunity (TXOP) sharing resource request. Various alternatives and additional features are also disclosed herein. [Brief explanation of the drawings]

[0010] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, in which like reference numerals refer to like elements and in which:

[0011] [Figure 1A] FIG. 1 is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented. [Figure 1B] 1B is a system diagram illustrating an exemplary wireless transmit / receive unit (WTRU) that may be used within the communications system shown in FIG. 1A, according to one embodiment. [Figure 1C] 1B is a system diagram illustrating an exemplary radio access network (RAN) and an exemplary core network (CN) that may be used within the communications system illustrated in FIG. 1A, according to one embodiment. [Figure 1D] 1B is a system diagram illustrating a further exemplary RAN and a further exemplary CN that may be used within the communication system shown in FIG. 1A according to one embodiment. [Figure 2] FIG. 1 illustrates an exemplary Medium Access Control (MAC) header, according to various embodiments. [Figure 3]FIG. 10 illustrates an example of an A-Control subfield of a high-efficiency (HE) variant of the high-throughput (HT) control field format. [Figure 4] FIG. 10 illustrates an example of a control subfield format according to a specific embodiment. [Figure 5] FIG. 10 is a diagram illustrating an example of a format of an HE MAC capability information field according to an embodiment. [Figure 6] FIG. 2 illustrates an example of a control frame with an extended frame control field format utilized in certain embodiments. [Figure 7] FIG. 10 illustrates an exemplary sequence diagram of operations using an extended control frame of an embodiment. [Figure 8] FIG. 2 is a flow diagram illustrating in greater detail a method for communicating in a wireless network according to one embodiment. [Figure 9] FIG. 1 illustrates a representative example of a High Efficiency (HE) High Throughput (HT) control field with an extended A-Control subfield, according to one embodiment. [Figure 10] 1 illustrates an example of a control information subfield of an Extended Bandwidth Query Report (BQR) control subfield of various embodiments. [Figure 11] 1 illustrates a sequence diagram of an exemplary operation using an extended BQRP (BQR Poll) trigger frame of various embodiments. [Figure 12] FIG. 1 illustrates an example of a control information subfield format using an enhanced high-efficiency (HE) link adaptation (HLA) control subfield in one embodiment. [Figure 13] FIG. 10 illustrates another option for the control information subfield within the extended HLA control subfield in various embodiments. [Figure 14] 1 is an example sequence diagram illustrating a method for communicating in a wireless network using unsolicited modulation and coding scheme (MCS) feedback (MFB) with enhanced HLA control, according to one embodiment. [Figure 15]1 is a sequence diagram illustrating a method for communicating in a wireless network using a soliciting MFB with extended HLA control, according to one embodiment. [Figure 16] FIG. 10 illustrates an exemplary control information subfield format in an embodiment using an extended trigger response scheduling (TRS) control field. [Figure 17] 10 illustrates an example of a control field in an embodiment where a control ID is set for an extended transmit opportunity (TXOP) shared resource request. [Figure 18] 10 illustrates an example of the format of a control information subfield within an extended TXOP shared resource request subfield as one option of various embodiments. [Figure 19] FIG. 10 illustrates an example of the format of a control information subfield within an extended TXOP shared resource request subfield as a second option of various embodiments. [Figure 20] 1 illustrates a method of communication in a wireless network using unsolicited TXOP shared resource requests, according to an exemplary embodiment. [Figure 21] 1 illustrates a method of communication in a wireless network utilizing a solicited TXOP shared resource request, according to an exemplary embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] 1A illustrates an exemplary communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple-access system that provides content, such as voice, data, video, messaging, and broadcasts, to multiple wireless users. The communication system 100 may enable the multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communication system 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tailed unique word discrete Fourier transform spread OFDM (ZT UW DFT-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multicarrier (FBMC), etc.

[0013] 1A, communications system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, and 102d, a radio access network (RAN) 104, a core network (CN) 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, although it will be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of WTRUs 102a, 102b, 102c, and 102d may be any type of device configured to operate and / or communicate in a wireless environment. For example, the WTRUs 102a, 102b, 102c, 102d may be referred to as stations (STAs), which may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile subscriber units, subscription-based units, pagers, cellular phones, personal digital assistants (PDAs), smartphones, laptops, notebooks, personal computers, wireless sensors, hotspot or Mi-Fi devices, IoT devices, watches or other wearables, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. The WTRUs 102a, 102b, 102c, and 102d may be referred to interchangeably as UEs.

[0014] The communications system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communications networks, such as the CN 106, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be any of a Base Transceiver Station (BTS), a NodeB (NB), an eNodeB (eNB), a Home NodeB (HNB), a Home eNodeB (HeNB), a Next Generation NodeB such as a gNodeB (gNB), a New Radio (NR) NodeB (NR NB), a site controller, an access point (AP), a wireless router, etc. Although the base stations 114a, 114b are each depicted as a single element, it will be understood that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0015] The base station 114a may be part of the RAN 104, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and / or base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for wireless services in a particular geographic area, which may be relatively fixed or may change over time. A cell may be further divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In one embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell or for any sector of the cell. For example, beamforming may be used to transmit and / or receive signals in desired spatial directions.

[0016] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0017] More particularly, as noted above, the communications system 100 may be a multiple-access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a and the WTRUs 102a, 102b, 102c in the RAN 104 may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 116 using Wideband CDMA (WCDMA). WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High Speed ​​Uplink (UL) Packet Access (HSUPA).

[0018] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE Advanced (LTE-A) and / or LTE Advanced Pro (LTE-A Pro).

[0019] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access, which may establish the air interface 116 using NR.

[0020] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may jointly implement LTE and NR radio access, e.g., using a dual connectivity (DC) principle. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions sent to and from multiple types of base stations (e.g., eNBs and gNBs).

[0021] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement a wireless technology such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), GSM EDGE (GERAN), or the like.

[0022] 1A may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a workplace, a home, a vehicle, a premises, an industrial facility, an air corridor (e.g., for use by drones), a road, etc. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a small cell, a picocell, or a femtocell. 1A, the base station 114b may have a direct connection to the Internet 110. Therefore, the base station 114b may not need to access the Internet 110 via the CN 106 / 115.

[0023] The RAN 104 may be in communication with the CN 106, which may be any type of network configured to provide voice, data, application, and / or VoIP services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have various quality of service (QoS) requirements, such as different throughput, latency, error resilience, reliability, data throughput, mobility, etc. The CN 106 may provide call control, billing services, mobile location services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions such as user authentication. Although not shown in FIG. 1A , it will be understood that the RAN 104 and / or CN 106 may be in direct or indirect communication with other RANs employing the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which may utilize NR radio technology, the CN 106 may also be in communication with another RAN (not shown) that employs GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0024] The CN 106 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network providing plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as TCP, UDP, and / or IP in the TCP / IP Internet protocol suite. The networks 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the network 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 or a different RAT.

[0025] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with a base station 114a, which may employ a cellular-based wireless technology, and with a base station 114b, which may employ an IEEE 802.2 wireless technology.

[0026] 1B is a system diagram illustrating an example of a WTRU 102. As shown in FIG. 1B, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a GPS chipset 136, and / or other peripherals 138. It will be understood that the WTRU 102 may include any subcombination of the foregoing elements while remaining consistent with an embodiment.

[0027] The processor 118 may be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), other types of integrated circuits (ICs), a state machine, etc. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. While FIG. 1B depicts the processor 118 and the transceiver 120 as separate components, it will be understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0028] The transmit / receive element 122 may be configured to transmit and receive signals to and from a base station (e.g., base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In one embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals, for example. In another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be understood that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0029] 1B depicts the transmit / receive element 122 as a single element, the WTRU 102 may include any number of transmit / receive elements 122. More particularly, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0030] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As mentioned above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as, for example, NR and IEEE 802.11.

[0031] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. Furthermore, the processor 118 may access information and store data in any type of suitable memory, such as non-removable memory 130 and / or removable memory 132. The non-removable memory 130 may include RAM, ROM, a hard disk, or any other type of memory storage device. The removable memory 132 may include a SIM card, a memory stick, a secure digital (SD) memory card, etc. In other embodiments, the processor 118 may access information and store data in memory that is not physically located on the WTRU 102, such as on a server or home computer (not shown).

[0032] The processor 118 may receive power from the power source 134 and may be configured to distribute and / or control the power to other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0033] The processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or instead of, information from the GPS chipset 136, the WTRU 102 may receive location information from base stations (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may obtain location information by way of any suitable location-determination method while remaining consistent with an embodiment.

[0034] The processor 118 may also be coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photos and / or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, etc. The peripherals 138 may include one or more sensors. The sensors may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor, a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, a humidity sensor, etc.

[0035] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with a particular subframe for both the uplink (e.g., for transmission) and the downlink (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit 139 to reduce and / or substantially eliminate self-interference through either hardware (e.g., chokes) or signal processing via a processor (e.g., a separate processor (not shown) or processor 118). In one embodiment, the WTRU 102 may include a half-duplex radio for transmission and reception of some or all of the signals (e.g., associated with a particular subframe for either the uplink (e.g., for transmission) or the downlink (e.g., for reception)).

[0036] 1C is a system diagram illustrating the RAN 104 and the CN 106, according to one embodiment. As noted above, the RAN 104 may employ E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0037] The RAN 104 may include eNode-Bs 160a, 160b, and 160c, although it will be understood that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, and 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, and 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, and 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0038] Each of the eNodeBs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the uplink (UL) and / or downlink (DL), etc. As shown in FIG. 1C, the eNodeBs 160a, 160b, 160c may communicate with each other via an X2 interface.

[0039] 1C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. While the above elements are shown as part of the CN 106, it will be understood that these elements may be owned and / or operated by entities other than the CN operator.

[0040] The MME 162 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface and may act as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, activating / deactivating bearers, selecting a particular serving gateway during initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies such as GSM and / or WCDMA.

[0041] The SGW 164 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to and from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions such as anchoring the user plane during handovers between eNodeBs, triggering paging when DL data is available to the WTRUs 102a, 102b, 102c, and managing and storing the context of the WTRUs 102a, 102b, 102c.

[0042] The SGW 164 may be connected to a PGW 166 that may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0043] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional fixed communication devices. For example, the CN 106 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. Additionally, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0044] Although the WTRU is depicted in FIGS. 1A-1D as a wireless terminal, it is contemplated that in some representative embodiments such a terminal may use a wired communication interface with the communication network (e.g., temporarily or permanently).

[0045] In an exemplary embodiment, the other network 112 may be a WLAN.

[0046] A WLAN in infrastructure basic service set (BSS) mode has an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or from the BSS. Traffic to a STA originating from outside the BSS may arrive through the AP and be sent to the STA. Traffic originating from a STA to a destination outside the BSS may be sent to the AP and delivered to the respective destination. Traffic between STAs within a BSS may be sent through the AP; for example, a source STA may send traffic to the AP, which then delivers the traffic to the destination STA. Traffic between STAs within a BSS may be considered or referred to as peer-to-peer traffic. Peer-to-peer traffic may be sent (e.g., directly) between a source STA and a destination STA using direct link setup (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and STAs within or using the IBSS (e.g., all STAs) may communicate directly with each other. The IBSS communication mode is sometimes referred to herein as an "ad hoc" communication mode.

[0047] When using 802.11ac infrastructure mode operation or a similar mode of operation, an AP may transmit beacons on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., a wide 20 MHz bandwidth) or a dynamically configured width. The primary channel may be the operating channel of the BSS and may be used by STAs to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access with collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. With CSMA / CA, STAs (e.g., all STAs), including the AP, may sense the primary channel. If the primary channel is sensed / detected by a particular STA and / or determined to be busy, the particular STA may back off. One STA (e.g., only one station) may transmit on a given BSS at any time.

[0048] High-throughput (HT) STAs may use 40 MHz wide channels for communication, for example, by combining a primary 20 MHz channel with adjacent or non-adjacent 20 MHz channels to form the 40 MHz wide channel.

[0049] A Very High Throughput (VHT) STA can support channels of 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz width. A 40 MHz and / or 80 MHz channel can be formed by combining contiguous 20 MHz channels. A 160 MHz channel can be formed by combining eight contiguous 20 MHz channels or two non-contiguous 80 MHz channels, sometimes referred to as an 80+80 configuration. In the 80+80 configuration, the channel-encoded data passes through a segment parser, which splits the data into two streams. Inverse Fast Fourier Transform (IFFT) processing and time-domain processing can be performed separately on each stream. The streams are mapped to two 80 MHz channels, and the data is transmitted by the transmitting STA. At the receiver of the receiving STA, the above operations for the 80+80 configuration can be reversed, and the combined data can be transmitted to the Medium Access Control (MAC).

[0050] Sub-1 GHz operating modes are supported by 802.11af and 802.11ah. The channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, while 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to representative embodiments, 802.11ah can support meter-type control / machine-type communication (MTC), such as MTC devices in macro coverage areas. MTC devices may have limited functionality, including specific features, such as support for (e.g., only support for) specific and / or limited bandwidths. MTC devices may include batteries with above-threshold battery life (e.g., maintaining a very long battery life).

[0051] A WLAN system may support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, and the WLAN system includes a channel that may be designated as a primary channel. The bandwidth of the primary channel may be equal to the largest common operating bandwidth supported by all STAs in a BSS. The bandwidth of the primary channel may be configured and / or limited by the STA from among all STAs operating in the BSS that support the smallest bandwidth operating mode. In an 802.11ah example, the primary channel of a STA (e.g., an MTC-type device) that supports (e.g., only supports) 1 MHz mode may be 1 MHz wide, even if the AP and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) configuration may depend on the status of the primary channel. For example, if the primary channel is busy because a STA (that only supports a 1 MHz mode of operation) is transmitting to the AP, all available frequency bands may be considered busy, even if most of the available frequency bands remain idle.

[0052] In the United States, the available frequency bands available for 802.11ah are 902MHz to 928MHz. In South Korea, the available frequency bands are 917.5MHz to 923.5MHz. In Japan, the available frequency bands are 916.5MHz to 927.5MHz. The total available bandwidth for 802.11ah is 6MHz to 26MHz depending on the country code.

[0053] 1D is a system diagram illustrating the RAN 104 and the CN 106, according to one embodiment. As noted above, the RAN 104 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0054] While the RAN 104 may include gNBs 180a, 180b, and 180c, it will be understood that the RAN 104 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, and 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, and 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, and 180c may implement MIMO technology. For example, the gNBs 180a and 180b may transmit and / or receive signals to and from the WTRUs 102a, 102b, and 102c using beamforming. Thus, for example, the gNB 180a may transmit and / or receive wireless signals to and from the WTRU 102a using multiple antennas. In one embodiment, the gNBs 180a, 180b, and 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on the unlicensed spectrum, and the remaining component carriers may be on the licensed spectrum. In one embodiment, the gNBs 180a, 180b, and 180c may implement Coordinated Multi-Point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNBs 180a and 180b (and / or 180c).

[0055] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with scalable numerology. For example, the OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or transmission time intervals (TTIs) of different or scalable lengths (e.g., including different numbers of OFDM symbols and / or different lengths of absolute time duration).

[0056] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c can communicate with the gNBs 180a, 180b, 180c without accessing another RAN (e.g., eNodeBs 160a, 160b, 160c, etc.). In a standalone configuration, the WTRUs 102a, 102b, 102c can utilize one or more gNBs 180a, 180b, 180c as mobility anchor points. In a standalone configuration, the WTRUs 102a, 102b, 102c can communicate with the gNBs 180a, 180b, 180c using signals in unlicensed bands. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with a gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as an eNode-B 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement a DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c at approximately the same time. In a non-standalone configuration, the eNode-Bs 160a, 160b, 160c may act as mobility anchors for the WTRUs 102a, 102b, 102c, and the gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0057] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, support for network slicing, DC, interworking between NR and E-UTRA, routing of user plane data to User Plane Functions (UPFs) 184a, 184b, routing of control plane information to Access and Mobility Management Functions (AMFs) 182a, 182b, etc. As shown in FIG. 1D , the gNBs 180a, 180b, 180c may communicate with each other via an Xn interface.

[0058] 1D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While the above elements are shown as part of the CN 106, it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0059] The AMF 182a, 182b may be connected to one or more gNBs 180a, 180b, 180c in the RAN 104 via an N2 interface and may function as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, supporting network slicing (e.g., handling different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, managing registration areas, terminating non-access stratum (NAS) signaling, mobility management, etc. Network slicing may be used by the AMF 182a, 182b to customize CN support for the WTRUs 102a, 102b, 102c based on the type of service being utilized by the WTRUs 102a, 102b, 102c. Different network slices may be established for different use cases, for example, services relying on Ultra-Reliable Low-Latency (URLLC) access, services relying on enhanced Massive Mobile Broadband (eMBB) access, services for MTC access, etc. The AMFs 182a, 182b may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that use other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies, such as WiFi.

[0060] The SMFs 183a, 183b may be connected to the AMFs 182a, 182b in the CN 106 via an N11 interface. The SMFs 183a, 183b may also be connected to the UPFs 184a, 184b in the CN 106 via an N4 interface. The SMFs 183a, 183b may select and control the UPFs 184a, 184b and configure the routing of traffic through the UPFs 184a, 184b. The SMFs 183a, 183b may perform other functions such as managing and assigning UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0061] The UPFs 184a, 184b may be connected to one or more gNBs 180a, 180b, 180c in the RAN 104 via an N3 interface, which provides the WTRUs 102a, 102b, 102c with access to packet-switched networks such as the Internet 110 and facilitates communication between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPFs 184, 184b may perform other functions such as routing and forwarding packets, enforcing user plane policy, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing a mobility anchor, etc.

[0062] The CN 106 may facilitate communication with other networks. For example, the CN 106 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. Additionally, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to their local DNs 185a, 185b through the UPFs 184a, 184b via an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

[0063] 1A-1D and the corresponding description thereof, one or more, or all, of the functions described herein with respect to one or more of the WTRUs 102a-d, base stations 114a-b, eNodeBs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-b, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and / or other elements / devices described herein may be performed by one or more emulation devices (not shown). An emulation device may be one or more devices configured to emulate one or more or all of the functions described herein. For example, the emulation device may be used to test other devices and / or to simulate network and / or WTRU functionality.

[0064] The emulation device can be designed to implement one or more tests of other devices in a lab environment and / or an operator network environment. For example, one or more emulation devices can be fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to perform one or more, or all, functions for testing other devices in the communication network. One or more emulation devices can be temporarily implemented / deployed as part of a wired and / or wireless communication network to perform one or more, or all, functions. The emulation device can be directly coupled to another device for testing purposes and / or can perform testing using wireless communication.

[0065] One or more emulation devices may also perform one or more functions (including all functions) without being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in test scenarios in a test lab and / or in test scenarios in non-deployed (e.g., test) wired and / or wireless communication networks to implement testing of one or more components. One or more emulation devices may be test equipment. Direct RF coupling and / or wireless communication via RF circuitry (which may, for example, include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0066] Various embodiments will be described below for clarity with reference to examples relating to 802.11 networks and related standards, with the understanding that reference to specific standards is not intended to limit the embodiments but is merely for illustrative purposes.

[0067] To improve spectral efficiency, 802.11ac introduced the concept of downlink multi-user MIMO (MU-MIMO) transmission, which transmits to multiple STAs in the same symbol time frame, for example, during a downlink OFDM symbol. The potential use of downlink MU-MIMO is currently being considered for 802.11ah as well. It is important to note that the downlink MU-MIMO used in 802.11ac uses the same symbol timing for multiple STAs, so interference of waveform transmissions to multiple STAs is not an issue. However, all STAs involved in MU-MIMO transmission with the AP must use the same channel or band, which limits the operating bandwidth to the smallest channel bandwidth supported by the STAs involved in MU-MIMO transmission with the AP.

[0068] Referring to FIG. 2, an exemplary medium access control (MAC) frame format 200 is described. Upon reception and verification, a STA shall be able to properly construct a subset of frames designated for transmission and decode a potentially different subset of frames. The specific subset of frames that a STA constructs and decodes is determined by the capabilities supported by that particular STA. A STA shall validate all received frames using a Frame Check Sequence (FCS) 205 and shall be able to interpret specific fields from the MAC header of every frame. A STA may transmit frames using frame formats defined in various 802.11 standards. A MAC frame format includes a set of fields that appear in a fixed order in every frame. FIG. 2 illustrates a general MAC frame format 200 for a Protocol Version 0 (PV0) MAC Protocol Data Unit (MPDU).

[0069] The High Throughput (HT) Control field 210 can be present in Control Wrapper frames and is present in QoS Data frames, (802.11ax) QoS Null frames, and management frames as determined by the +HTC subfield of the Frame Control field. The HT Control field 210 transmitted by non-Chinese mmWave Multi-Gigabit (non-CMMG) STAs can have three different variants: an HT variant, a Very High Throughput (VHT) variant, and a High Efficiency (HE) variant. These variant formats are distinguished by the values ​​of B0 and B1, as defined in Table 1 below.

[0070] [Table 1]

[0071] Figure 3 shows the format 300 of the A-Control (Aggregated Control) subfield of the HT Control field of the HE variant. The A-Control subfield is 30 bits long. The Control List subfield 305 contains one or more control subfields. Figure 4 shows the format 400 of each control subfield.

[0072] The Control ID subfield 405 indicates the type of information carried in the Control Information subfield 410. The length of the Control Information subfield 410 is fixed for each non-reserved value of the Control ID subfield 405. The Control ID subfield 405 values ​​and their corresponding lengths of the Control Information subfield 410 are defined in Table 2 below.

[0073] [Table 2]

[0074] Referring to Figure 5, there is shown the format of the HE MAC capabilities information field 500. An HE STA declares itself as an HE STA by sending an HE Capabilities element. The HE Capabilities element includes the following subfields: Element ID, Length, Element ID Extension, HE MAC Capability Information, HE PHY Capability Information, Supported HE-MCS and NSS Set, and PPE Threshold (optional).

[0075] The HE Link Adaptation Support subfield 505 of the HE MAC Capability Information field 500 is shown in Table 3 below.

[0076] [Table 3]

[0077] Link adaptation using the HE Link Adaptation (HLA) control subfield was previously defined in 802.11ax. Multiple instances of the HLA control subfield with the Modulation and Coding Scheme (MCS) Request (MRQ) field equal to 1 appearing within a single PPDU shall be interpreted by the receiver as a single request for link adaptation feedback.

[0078] An MFB feedback (MFB) requester can specify the resource unit (RU) index and bandwidth (BW) for which link adaptation feedback is requested. Upon receiving an HLA control subfield with an MRQ subfield equal to 1, the MFB responder calculates the HE-MCS, NSS, and DCM for the RU and BW specified in the MRQ, but these estimates are based on the same RU in the PPDU carrying the MRQ. The PPDU carrying the MRQ can contain the RU requested for the MFB. The MFB responder labels the result of this calculation using the MRQ sequence identifier (MSI) value from the HLA control subfield in the received frame carrying the MRQ. The MFB responder can include the received MSI value in the MSI field of the corresponding response frame. In the case of a delayed response, this allows the MFB requester to associate the MFB with the soliciting MRQ.

[0079] Estimates of the unsolicited HE-MCS, NSS, DCM, BW, and RU reported in the HLA control subfield transmitted by the STA may be calculated based on the most recent PPDU received by the STA that matches the descriptions indicated by the PPDU format, Tx beamforming, and coding type subfields in the same HLA control subfield.

[0080] Multi-link operation (MLO) was introduced in 802.11be to allow a non-AP multi-link device (MLD) to discover, authenticate, associate, and establish multiple links with an AP MLD. An AP associated with an AP MLD (referred to as a reporting AP) can advertise the operating capabilities and parameters of another AP associated with the same AP MLD (referred to as a reporting AP) by including a multi-link element. Each link allows channel access and frame exchange between the non-AP MLD and the AP MLD based on the supported capabilities exchanged during association.

[0081] An initial problem may arise in requests and / or responses via the frame control field in an MLO system. In 802.11 mmW operation, robust communication suitable for exchanging control information over an mmW link may require strong directionality between the transmitter and receiver, and establishing this communication may take longer than lower-bandwidth communication, e.g., sub-7 GHz. Furthermore, in mmW bands, communication quality may be easily affected by multiple factors, e.g., the movement of surrounding objects, which may make the transmission of control / management frames more susceptible. Therefore, an extended MAC header that can convey mmW link request and response information via the frame control field carried in control / management frames transmitted in sub-7 GHz bands may be preferable. In general, to take advantage of multi-link operation, it would be beneficial to introduce a cross-link signaling mechanism that allows a frame transmitted on one link to carry request / response information for another link different from the link used to transmit this frame. In certain embodiments, this cross-link signaling can be achieved by extending the existing frame control field design.

[0082] Additional issues may be related to requests and / or responses via the Aggregation Control (A-Control) field in currently defined MLO systems. In the current A-Control field (e.g., 300 in FIG. 3), the content of the control information subfield (e.g., 410 in FIG. 4) refers to information about the link for which the frame carries the control information subfield. However, in mmW operation, the mmW link may be fragile. It may be easily affected by changes in the surrounding environment, e.g., the movement of surrounding objects, which may require more frequent beam configuration / reconfiguration in the mmW link. Therefore, it may be beneficial to allow some request and / or response information related to the mmW link to be transmitted over a more stable link, e.g., a sub-7 GHz link. Therefore, embodiments disclosed herein use an extended A-Control field, whereby the A-Control field carried by frames transmitted in sub-7 GHz can include request and / or response information for the mmW link. Thus, certain embodiments disclosed herein relate to a crosslink signaling mechanism that allows a frame transmitted on one link to carry request / response information for another link different from the link used to transmit the frame. In one embodiment, this crosslink signaling can be achieved by extending the existing A-Control field design in MLO systems.

[0083] In one embodiment, referring to FIG. 6 , the extended frame control field 600 may be used to exchange response or request information for another link different from the link over which the frame carrying the frame control field is transmitted. For example, in one embodiment, a STA supporting an mmW link may be capable of supporting multi-link operation (MLO). In this example, when the mmW link is enabled, additional links, e.g., sub-7 GHz links, may also be enabled. In this example, the mmW link may be referred to as a “subordinate” link, and the enabled sub-7 GHz link may be referred to as a “primary” or “anchor” link. Note that the multi-link operation of the embodiments described herein may apply to any type of primary and / or secondary link where it may be beneficial to communicate control information over the primary link to operate the secondary link. Examples of different links may include 802.11, 3GPP, Bluetooth, UWB links, or any other existing or future primary / secondary links where similar advantages may be obtained. Therefore, the embodiments described herein are not limited to any particular primary or secondary link, except as claimed herein.

[0084] Extended Control Frame: In one embodiment, a control frame can be used to indicate that the frame includes an HT Control field and that this HT Control field may contain information for another link. With reference to FIG. 6 , for example, if a control frame 600 is transmitted on a sub-7 GHz band (e.g., 2.4 GHz, 5 GHz, or 6 GHz) link, i.e., Link 1, and the +HTC subfield 605 is set to 1, the information carried in the HT Control field can indicate request or response information for another link (e.g., an mmW or tributary link), i.e., Link 2. In other words, the +HTC subfield 605 can be set to 1 in a control frame 600 transmitted by a STA to another STA on one link to indicate that the frame includes an HT Control field that carries a response or request for another link. FIG. 6 illustrates an exemplary frame control field format 600 when the Type subfield 610 is set to 1 (representing a control frame) and the Subtype subfield 615 is set to 15 (or 0 or 1). Alternatively, it may be a combination of any value in the Subtype subfield 615 and one in the Type subfield 610. Table 4 below shows exemplary valid Type and Subtype combinations for the enhanced control frame signaling of FIG. 6, according to certain embodiments.

[0085] [Table 4]

[0086] 6 shows an exemplary extended frame control field format 600 present when the frame is a control frame, e.g., when the Type subfield is set to 1 and the Subtype subfield is set to 15 (or 0, 1, or other value). If the Type subfield 610 is set to 1 (representing a control frame), the Subtype subfield 615 is set to 15 (or 0 or 1 or any other value), and the +HTC subfield 605 is set to 1, the extended control frame identifies the presence of request or response information for another link (e.g., mmW or tributary link). The signaling here is for a different link than the link on which the extended control frame is transmitted. This is referred to in one embodiment as "cross-link signaling."

[0087] For example, if it is an HE Link Adaptation (HLA) control in the A-Control subfield, it represents link adaptation information (e.g., requested MCS / Nss or unsolicited MCS / Nss) for another link, e.g., an mmW link or a subordinate link. If it is a Bandwidth Query Report (BQR) control in the A-Control subfield, it includes a Bandwidth Query Report based on a Bandwidth Query Report operation to support UL MU transmission in another link, e.g., an mmW link or a subordinate link.

[0088] In another example, if it is a TRS control in the A-Control subfield, it contains trigger response scheduling (TRS) information to request a TB PPDU that may be transmitted on another link different from the link carrying the extended control frame. The information carried in the control information subfield in the TRS control subfield may indicate information about the link on which the TB PPDU is transmitted.

[0089]

[0046] Embodiments of an extended data / management frame will now be described. In one embodiment, an extended HT control field may be carried in an extended data / management frame. This extended HT control field may indicate response / request information for subordinate links other than the link over which the data / management frame is transmitted, e.g., mmW links or subordinate links. Table 5 below shows exemplary valid type and subtype combinations for extended management / data frames, according to some embodiments.

[0090] [Table 5]

[0091] In one embodiment, a capability to indicate HT control information of another link (e.g., mmW link, subordinate link) other than the link over which the frame is transmitted using the extended frame control field may be included in a subfield of the MAC Capability Information field. If a STA indicates that it supports the extended frame control field, e.g., if this subfield of the MAC Capability Information field is set to 1, an AP can request a non-AP STA to transmit information of the other link, or the STA can transmit unsolicited information of the other link carried in the extended frame control field to another STA. If a STA does not indicate that it supports the extended frame control field, e.g., if this subfield of the MAC Capability Information field is set to 0, an AP cannot request a non-AP STA to transmit the extended frame control field, or the STA cannot transmit unsolicited information carried in the extended frame control field to another STA.

[0092] Referring to FIG. 7, a method for communicating within a wireless network using an extended control frame for crosslink signaling is shown and described. In one embodiment, a STA multilink device (MLD) can send a request to another STA MLD via an extended control frame for information on link m, e.g., an mmW link or a tributary link. Link m may be different from the link on which the extended control frame is transmitted (e.g., link n). As shown in FIG. 7, a first station (STA MLD1) transmits an extended control frame 705 with the +HTC subfield set to 1 (as described above). It can request crosslink information, e.g., HLA, BQR, etc., from a second station (STA MLD2). Upon receiving the extended control frame 705 with +HTC=1 from MLD1, STA MLD2 can respond with an extended control frame 710 with +HTC set to 1. The extended control frame can carry the information requested by STA MLD1. This information can represent a crosslink different from the link on which the extended control frame is transmitted, e.g., link m. Furthermore, STA MLD2 can also send unsolicited information of link m (e.g., mmW link / subordinate link) to STA MLD1 on link n (e.g., anchor link / primary link) different from link m. In other words, STA MLD2 may directly send an extended control frame 710 with +HTC set to 1 carrying information of link m on link n, where link m may not be the same as link n.

[0093] It should be noted that the method 700 described with reference to FIG. 7 may additionally or alternatively utilize the aforementioned extended data / management frames using extended control frame operations.

[0094] We now describe another embodiment that utilizes an extended A-Control subfield for crosslink signaling, which can be used to obtain response or request information for another link different from the link over which the frame carrying this A-Control subfield is transmitted in a manner similar to the previous embodiment.

[0095] Referring to FIG. 8, a method 800 for a multilink STA to communicate with a multilink device in a wireless network is shown. In method 800, a first wireless link m, e.g., a sub-7 GHz link, is used to communicate between ML STA1 and ML STA2. ML STA1 transmits a frame to ML STA2 via link m (805). The frame includes a high-throughput control (+HTC) field, a newly defined control field, or another type of field indicating that the frame contains control information for operating a different wireless link n, e.g., an mmWave link, with ML STA2. ML STA2 transmits a second frame back to ML STA1 via link m (810). The second frame includes a high-throughput control (+HTC) field, a newly defined control field, or another type of field indicating that the second frame contains control information for operating link n with ML STA1. The operations on the second wireless link n 815 are based on information contained in frames exchanged between ML STA1 and ML STA2 over wireless link m, and ML STA1 and ML STA2 can simultaneously communicate with each other over both link m and link n 820. Although not shown in FIG. 8, control information for maintaining the second wireless link n may be continuously communicated over the first wireless link m.

[0096] Referring to Figure 9, in one embodiment, a STA may utilize an extended A-Control subfield. In the example of Figure 9, an exemplary HE HT control field 900 is shown including an extended A-Control subfield 905, which signals request or response information for a secondary link different from the primary link used to transmit the frame carrying the extended A-Control subfield 905. Of note, depending on the STA capabilities or control ID of the A-Control field, the HE HT control field may also be a legacy A-Control field. The HE HT control field 900 including the extended A-Control subfield 905 may also be referred to herein as an "extended" HT control field.

[0097] An embodiment of the extended BQR control will now be described with reference to Figure 10. The extended BQR control subfield 1000 may contain a bandwidth query report (BQR) used for a bandwidth query report operation on the link used for transmission of the frame carrying the BQR control (i.e., the primary link) or another link different from the link used for transmission of this frame (i.e., the secondary link). In a particular embodiment, the link indication subfield 1005 carries information indicating that the available channel bitmap represents the link on which the frame carrying the extended BQR control information is transmitted or another link not used for transmission of this frame. For example, when the link indication subfield 1005 is set to 0, the available channel bitmap subfield 1010 indicates available channels for STAs on a link used for transmissions carrying the extended BQR control, e.g., a low-bandwidth link (or a sub-7 GHz link), whereas when the link indication subfield 1005 is set to 1, the available channel bitmap subfield 1010 indicates available channels for STAs on a link not used for transmissions containing the extended BQR control (secondary link), e.g., an mmW link or a tributary link. FIG. 9 illustrates an exemplary control information subfield format for the extended BQR control subfield 1000, according to one embodiment. Note that one or more bits may be used to indicate a particular link. In other words, the link indication subfield 1005 may include one or more bits. FIG. 10 illustrates an exemplary control information subfield format for the extended BQR control subfield 1000, according to a particular embodiment.

[0098] Referring to FIG. 11, a method 1100 of communicating in a wireless network using an extended BQRP trigger frame will be described. A non-AP MLD can transmit an extended BQR to assist its AP MLD in allocating DL MU and UL MU resources (i) on the link on which the frame carries BQR information, or (ii) on another link different from the link on which the frame carries BQR information. A non-AP MLD can implicitly transmit a BQR in the extended BQR control subfield of a frame sent to the AP MLD (unsolicited extended BQR) or explicitly transmit a BQR in a frame sent to the AP MLD in response to a BQRP trigger frame (solicited extended BQR). A solicited or unsolicited extended BQR can be carried in an extended data frame with an extended HT control field (as described above) or in an extended control frame with an extended HT control field (as shown in FIG. 10).

[0099] In one embodiment, one bit in the EHT variant common information field of the trigger frame 1105 may be used to indicate to the receiving STA (MLD) of the trigger frame that the BQR information of another link other than the link on which the trigger frame is transmitted is requested. For example, one option is to use B22 (or any bit from B56 to B63) of the EHT variant common information field as a "different link request," which indicates request information of another link, e.g., an mmW link or a subordinate link other than the link on which the trigger frame is transmitted. In another embodiment, an option is to add one bit to the trigger-dependent common information subfield of the EHT variant common information field when the trigger type is a BQRP trigger frame. For example, if this bit is set to 1, it indicates that BQR information of a secondary link, e.g., an mmW link or a subordinate link, is requested, while if this bit is set to 0, it indicates that BQR information of the primary link on which the trigger frame 1105 is transmitted is requested. Alternatively, N (N>1) bits may be used for "link indication." For example, N (e.g., N=4) bits may be carried in the Trigger Dependent Common Information subfield of the EHT Variant Common Information field or any N (e.g., N=4) bits of B22, B56-B63, where N bits follow the definition of the Link ID subfield of the Link ID Information subfield of the Common Information field of the Basic Multilink Element.

[0100] 11 illustrates a method 1100 for a WTRU to communicate in a wireless network using an extended BQRP trigger frame. When an AP-MLD transmits an extended BQRP trigger frame 1105 to a non-AP MLD requesting a BQR from the non-AP MLD on another link / secondary link different from the link on which the extended BQRP trigger frame 1105 is transmitted (e.g., the other link may be an mmW link or a subordinate link), the non-AP MLD sends back an extended data frame 1110 carrying an extended HT control field indicating a BQR on the secondary link / subordinate link.

[0101] In another embodiment, the response frame 1110 may be an extended control or management frame carrying an extended HT control field. The link used to send back the extended data / management / control frame 1110 carrying the extended HT control field may be the same link over which the AP MLD sends the trigger frame 1105.

[0102] Disclosed herein are embodiments of cross-link signaling using extended HLA control. In some embodiments, the extended HLA control subfield may include link adaptation related information (e.g., requested MCS / Nss or unsolicited MCS / Nss) for another link (e.g., an mmW link or a subordinate link) different from the link over which the frame carrying the extended HLA control subfield is transmitted.

[0103] 12 and 13 show exemplary formats of the control information subfield in the extended HLA control subfields 1200 and 1300, respectively, according to different embodiments. FIG. 12 shows that one bit is allocated to the link indication subfield 1205, which indicates whether the HLA control subfield represents link quality information (e.g., MCS, Nss) of the link over which the frame carrying this HLA control subfield is transmitted. For example, if the link indication subfield is 1, this indicates that the information carried in the HLA control subfield is for another link (e.g., mmW link, dependent link) different from the link over which the frame carrying this HLA control subfield is transmitted. Alternatively, if the link indication subfield is 0, this indicates that the information carried in the HLA control subfield is for the link associated with the frame carrying this HLA control subfield, i.e., the primary link.

[0104] Figure 13 illustrates an embodiment in which two bits are allocated to the link / format indication subfield 1305. An example encoding of these two bits is shown in Table 6 below, and an example encoding of the link / format indication subfield 1305 in the control information subfield in the extended HLA control is shown in Figure 13.

[0105] [Table 6]

[0106] Referring to FIG. 14, a method 1400 of wireless communication using extended HLA control that enables extended unsolicited MCS feedback (MFB) operation is shown. In the example method 1400, MLD1 transmits a frame 1405 on link m without requesting MFB. MLD2 transmits an extended unsolicited MFB 1410 (with the unsolicited MFB subfield set to 1 and the link indication subfield set to 1). The information carried in the extended HLA A-Control subfield may include the MCS, Nss, of the RU indicated by the RU Allocation subfield combined with the PS 160 and BW subfields. This information is based on the most recent PPDU received by MLD2 for link m that matches the description indicated by the PPDU Format, Tx Beamforming, and Coding Type subfields in the extended HLA control. Link n may not be the same as link m.

[0107] For example, when these two bits are set to 00, it means that it is an HLA control subfield, when these two bits are set to 01, it means that it is an ELA (EHT Link Adaptation) control subfield, when these two bits are set to 10, it means that the frame is an ELA control subfield or an extended ELA subfield that carries associated link information (e.g., MCS / Nss) for another simultaneous link (e.g., an MMW link or a subordinate link) different from the link that carries this extended HLA control subfield, when these two bits are set to 11, it means that it is an ELA subfield or an extended ELA subfield that carries associated link information (e.g., MCS / Nss) for another AP (e.g., a shared AP or a slave AP or a coordinating AP) or AP-MLD (e.g., a shared AP-MLD or a slave AP-MLD or a coordinating AP-MLD).

[0108] Referring to FIG. 15, a wireless communication method 1500 using crosslink signaling with extended HLA control can be used to enable extended solicited MFB operation. FIG. 14 illustrates an example operation of solicited MFB. In this example, MLD1 transmits a frame 1505 carrying an extended HLA subfield with MRQ=1 and link indication=1 on link m. MLD2 transmits an extended solicited MFB 1510 (MRQ=0, unsolicited MFB subfield set to 0, and link indication subfield set to 1) on link n. Information carried in the response frame 1510 (sent from MLD2 on link n) with an extended HLA A-Control subfield may include the MCS, Nss, of the RU indicated by the RU Allocation subfield combined with the PS 160 and BW subfields specified in the frame carrying the extended HLA subfield with MRQ=1. Link n may not be the same as link m. Alternatively, in the request MFB, the STA may include an extended HLA for one link but request an estimate for the PPDU transmitted on another link, and the receiving STA of this PPDU can transmit the estimated MCS / Nss on the link on which the requested MFB is transmitted.

[0109] An embodiment of the extended TRS control is also described with reference to FIG. 16. In one embodiment, the extended trigger response scheduling (TRS) control may be used to request a TB PPDU to be transmitted on a link other than the link carrying the extended TRS control. FIG. 16 illustrates an example format of the control information subfield in the extended TRS control field 1600. In this example, the link indication field 1605 requests the receiving MLD whether to transmit the TB PPDU on the same link as the frame carrying the extended TRS control field. For example, if the link indication subfield 1605 is set to 0, it indicates that the requested TB PPDU is to be transmitted on the same link as the link carrying the extended TRS control field, and if the link indication subfield 1605 is set to 1, it indicates that the requested TB PPDU is to be transmitted on a link other than the link carrying the extended TRS control field 1600 (e.g., an mmW link or a tributary link).

[0110] In another embodiment, referring to Figure 17, crosslink signaling may utilize an extended TXOP shared resource request configuration 1700. In one embodiment, the extended TXOP shared resource request may indicate a request for resource allocation for P2P (PC5) traffic. Specifically, this embodiment may indicate whether the STA transmitting the frame carrying the extended TXOP shared resource request includes low-latency traffic. For example, the extended TXOP shared resource request is included in the A-Control subfield as a new type of control information, an example of which is shown in Table 7 below. Figure 17 illustrates the control subfield when the control ID 1705 represents the extended TXOP shared resource request 1710.

[0111] [Table 7]

[0112] 18, embodiments having an extended TXOP shared resource request subfield 1800 may include additional information regarding restricted target wake time (TWT) or R-TWT traffic (i.e., latency sensitive traffic) for a peer STA, such as Restricted TWT Presence 1805 and / or Restricted TWT Information 1810. For example, Restricted TWT Traffic Information subfield Presence 1805 is set to 1 if Restricted TWT Traffic Information subfield 1810 is present, and is set to 0 otherwise. If a STA has latency sensitive traffic for its peer STA, it sets Restricted TWT Traffic Information subfield Presence 1805 to 1.

[0113] 18 illustrates an embodiment with one option (Option 1) of an example format of the control information subfield in the extended TXOP shared resource request subfield 1800. There may be multiple options for defining the restricted TWT traffic information subfield 1810.

[0114] Option 1a: The Constrained TWT Traffic Information subfield 1810 may include a Delta Delay Bound subfield (not shown). The Delta Delay Bound subfield may contain an unsigned integer representing the difference between the actual delay bound and a delay bound threshold that may be defined by the system. The actual delay bound specifies the maximum amount of time, in microseconds, allowed for the transfer of an MSDU or A-MSDU belonging to a P2P traffic flow, as measured between the arrival of the first MDU of the MSDUs that make up the MDU or A-MSDU from the local MAC SAP to the local MAC sublayer and the completion of successful transmission or retransmission of the MSDU or A-MSDU to its destination. This delta delay bound has a value only if it is less than the threshold. For example, if the actual delay bound is greater than or equal to the threshold, the Delay Bound subfield is set to 0; otherwise, the Delay Bound subfield is set to the integer difference between the actual delay bound and the threshold. The threshold may or may not be included in the Limited TWT Traffic Information subfield 1810.

[0115] Option 1b: The Constrained TWT Traffic Information subfield 1810 may include a Delta Bound subfield (not shown). The Delay Bound subfield may contain a value that specifies the maximum amount of time, in microseconds, allowed for the transfer of an MSDU or A-MSDU belonging to a P2P traffic flow, as measured between the time the first MDU of the MSDUs that make up the MDU or A-MSDU arrives at the local MAC sublayer from the local MAC SAP and the time successful transmission or retransmission of the MSDU or A-MSDU to its destination is completed. The value set in the Delay Bound subfield may be a quantized value.

[0116] Referring to FIG. 19, an alternative embodiment with another option for the format of the control information subfield in the extended TXOP shared resource request subfield 1900 is shown. In the example of FIG. 19, a link indication subfield 1905 is shown, which indicates the link for which a channel width (i.e., the maximum bandwidth of the P2P link) and requested medium time are requested for P2P transmission. The link indication subfield 1905 includes N bits, where N >= 1. For example, for N = 1, if the link indication subfield 1905 is set to 1, the maximum channel width (indicated in the channel width subfield 1902) and requested medium time (indicated in the requested medium time subfield 1904) may apply to a secondary link (e.g., an mmW link or a tributary link) other than the link over which the frame carrying the extended TXOP share is transmitted. Otherwise, it may indicate that the maximum channel width (indicated in the channel width subfield 1902) and requested medium time (indicated in the requested medium time subfield 1904) apply to the link over which the frame carrying the extended TXOP share is transmitted. If the link indication subfield 1905 indicates a link ID, the maximum channel width (indicated in the channel width subfield 1902) and required medium time (indicated in the required medium time subfield 1904) apply to the link whose link ID is indicated in the link indication subfield 1905.

[0117] This TXOP shared resource request may be set by the AP or the AP-MLD. When a frame carrying a TXOP shared resource request is sent from an AP, the AP can use one or more bits in the TXOP shared resource request to indicate to another MLD that it requests the AP / AP-MLD to indicate whether there is P2P traffic in any link. When the sender of a frame carrying a TXOP shared resource request is an AP / AP-MLD, the Restricted TWT Traffic Information Presence subfield 1910 and the Restricted TWT Traffic Information subfield 1915 are reserved.

[0118] Here, embodiments related to the operation of an enhanced TXOP shared resource request are described. In various embodiments, enhanced TXOP sharing may be unsolicited or solicited. In other words, a non-AP MLD can transmit P2P traffic information via an extended TXOP A-Control subfield triggered by an AP MLD. Alternatively, P2P traffic information can be transmitted via an extended TXOP A-Control subfield without a request from the AP MLD.

[0119] Referring to FIG. 20, a wireless communication method 2000 using an unsolicited TXOP shared resource request is shown. An unsolicited AP MLD can transmit an unsolicited frame 2005 carrying an extended TXOP shared resource request in the A-Control field to an AP MLD. The extended TXOP shared resource request can indicate to the AP that there is P2P traffic requiring resource allocation and that there is delayed traffic, i.e., the presence of R-TWT traffic. FIG. 18 illustrates an example operation of the control information subfield 1800 for an unsolicited TXOP shared resource request. In this example, R-TWT traffic (delay-sensitive traffic) is present in P2P traffic, e.g., the presence of restricted TWT traffic information subfield 1805 is set to 1.

[0120] FIG. 21 illustrates a wireless communication method 2100 for soliciting TXOP shared resource requests using extended crosslink signaling. After receiving a TXOP shared resource request 2105 from an AP / AP MLD, the non-AP MLD can transmit a request frame 2110 to the AP / AP MLD, with the extended TXOP shared resource request in the A-Control field. FIG. 18 illustrates an example configuration of a solicited TXOP shared resource request. In this example, the non-AP MLD is requesting resource allocation for P2P traffic and indicates the presence of R-TWT traffic (delay-sensitive traffic) within the P2P traffic (e.g., the Restricted TWT Traffic Information subfield 1805 is set to 1). The P2P traffic may be on a link different from the link on which the frame exchange is performed.

[0121] In the various embodiments described above, it is important for the MLD to notify neighboring devices of its ability to perform crosslink signaling. In one embodiment, a report or request via the extended A-Control subfield (e.g., the extended A-Control subfield may include BQR, HLA, etc.) for another link (e.g., mmW link, subordinate link) different from the link carrying the report or request information may be included in one or more subfields of the MAC Capabilities Information field. In other words, the ability to support the extended BQR control, the extended HLA control, or any control ID included in the A-Control subfield may be indicated as a whole or individually. For example, if a STA indicates that it supports the extended A-Control subfield (e.g., the corresponding subfield in the MAC Capabilities Information field is set to 1), it means that it supports the extended A-Control subfield including all control IDs. Conversely, if a STA indicates that it does not support the extended A-Control subfield (e.g., the corresponding subfield in the MAC Capabilities Information field is set to 0), it means that it does not support the extended A-Control subfield including all control IDs.

[0122] Alternatively, the MAC Capability Information field may include multiple subfields that individually indicate whether a STA supports a particular extended control ID. For example, if a STA indicates support for the extended BQR control subfield (e.g., if the corresponding subfield in the MAC Capability Information field is set to 1), an AP can request the STA to transmit the extended BQR control subfield, or the STA can transmit unsolicited information carried in the extended BQR control subfield to another STA (if both STAs support the extended BQR control subfield). If a STA does not indicate support for the extended BQR control subfield (e.g., if the corresponding subfield in the MAC Capability Information field is set to 0), an AP cannot request a non-AP STA to transmit the extended BQR control subfield, or the STA cannot transmit unsolicited information carried in the extended BQR control subfield to another STA (if either the receiving STA or the transmitting STA does not support the extended BQR subfield). Similar rules apply to whether support for the extended HLA control subfield or the extended TXOP sharing subfield can be communicated.

[0123] While features and elements of the present embodiments are described in preferred embodiments and in specific combinations, each feature or element can be used alone without other features and elements of the preferred embodiments, or in various combinations with or without other features and elements of the present embodiments. Furthermore, while the embodiments described herein contemplate 802.11-specific protocols, it will be understood that the embodiments are not limited thereto and may be applied to other wireless systems where appropriate advantages are obtained. Furthermore, even in 802.11-specific embodiments, other existing or future signaling and control fields can be utilized for crosslink signaling without departing from the scope of the embodiments described herein.

[0124] In the example designs and procedures, SIFS is used to denote various frame intervals, however, all other frame intervals, such as RIFS, AIFS, DIFS, or other agreed time intervals, are applicable to similar solutions. Additionally, while sub-7 GHz links / bands are used to denote links in MLO systems where control / management frames may be transmitted in mmW links / bands, there are no limitations on the frequency spectrum, and any link in a multi-link system, for example, with more stable and efficient capabilities for control information, may be applied to the embodiments described herein.

[0125] Additionally, although reference is made to a first field / subfield / element / subelement within a second field / subfield / element / subelement / frame, the first field / subfield / element / subelement may also be transmitted in other fields / subfields / elements / subelements / frames to indicate the same information.

[0126] Although features and elements are described above in particular combinations, those skilled in the art will understand that each feature or element can be used alone or in any combination with the other features and elements. Furthermore, the methods described herein can be implemented in a computer program, software, or firmware embodied in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted via wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random-access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). A processor in combination with software can be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. 1. A method for use in a multi-link (ML) STA, comprising:

11. A method comprising: transmitting a frame to an ML device over a first wireless link, the frame including a high throughput control (+HTC) field indicating that the frame includes control information for a second wireless link between the ML STA and the ML device, the second wireless link being different from the first wireless link.

2. The method of claim 1 , wherein the control information includes request or response information for establishing or maintaining the second wireless link.

3. The method of claim 1 , wherein the first wireless link is in a sub-7 GHz frequency band and the second wireless link is in a millimeter wave frequency band.

4. 2. The method of claim 1, wherein the control information is contained in an A-Control subfield of a high-efficiency (HE) variant high-throughput (HT) control field.

5. 2. The method of claim 1, further comprising receiving a frame from the ML device over the first wireless link, the frame including a high throughput control (+HTC) field indicating that the received frame includes second control information for the second wireless link.

6. The method of claim 5 , wherein the second control information includes request or response information for establishing or maintaining the second wireless link.

7. The method of claim 6 , further comprising operating the second wireless link with the ML device using the second control information received over the first wireless link.

8. The method of claim 1 , wherein the control information includes an extended bandwidth query report (BQR) subfield.

9. The method of claim 1 , wherein the control information includes a high-efficiency link adaptation (HLA) control subfield.

10. The method of claim 1 , wherein the control information includes an enhanced trigger response scheduling (TRS) control field.

11. The method of claim 1 , wherein the control information includes an extended transmission opportunity (TXOP) shared resource request.

12. A multi-link (ML) STA, A transceiver; a processor in communication with the transceiver; wherein the processor and the transceiver an ML STA configured to transmit a frame to an ML device over a first wireless link, the frame including a high throughput control (+HTC) field indicating that the frame includes control information for a second wireless link between the ML STA and the ML device, the second wireless link being different from the first wireless link.

13. The ML STA of claim 12 , wherein the control information includes request or response information for establishing or maintaining the second wireless link.

14. 13. The ML STA of claim 12, wherein the first wireless link is in a sub-7 GHz frequency band and the second wireless link is in a millimeter wave frequency band.

15. The ML STA of claim 12, wherein the control information is included in an A-Control subfield of a high-efficiency (HE) variant high-throughput (HT) control field.

16. 13. The ML STA of claim 12, wherein the processor and the transceiver are further configured to receive a frame from the ML device over the first wireless link, the frame including a high throughput control (+HTC) field indicating that the received frame includes second control information for the second wireless link.

17. 17. The ML STA of claim 16, wherein the second control information includes request information or response information for establishing or maintaining the second wireless link.

18. 18. The ML STA of claim 17, wherein the processor and the transceiver are further configured to establish the second wireless link with the ML device using the second control information received over the first wireless link.

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