Method, apparatus and process for CSMA and spatial reuse in sub-channelized WLAN

Abstract

Provided are methods, apparatus, and systems for using at least one subchannel of a physical channel for uplink communication, wherein the physical channel may include a set of resources within a first and second channel boundary, whereby the physical channel may include multiple subchannels, each of which may include a subset of physical channel resources and may have at least one subchannel boundary that does not overlap with the first or second channel boundary. A typical apparatus includes a station (STA), the STA including: a processor, and a transmit / receive unit configured to: transmit control information including a subchannel SIG field for indicating a STA identity via an uplink, receive a trigger frame for indicating one or more subchannels that can be obtained from multiple subchannels, determine a subchannel to be obtained from the one or more subchannels, and use the obtained one or more subchannels and transmit data via an uplink.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications, and in particular to a method, device and system for carrier sense multiple access (CSMA) and spatial reuse processes (eg in a wireless local area network (WLAN)). Background Art

[0002] Typically, a WLAN using an infrastructure basic service set (BSS) mode has an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. Traffic between STAs can be sent through the AP. The AP can receive traffic from a source STA and can transmit the traffic to a destination STA. Alternatively, the traffic can also be sent directly between the source and destination STAs. A WLAN using an independent BSS (IBSS) mode may not have an AP and can allow all STAs to communicate directly with each other. Summary of the invention

[0003] Provided are methods, devices, and systems for using at least one subchannel of a physical channel for uplink communication. The physical channel may include a set of resources within a first and second channel boundary, whereby the physical channel may include multiple subchannels, each of which may include a subset of physical channel resources and may have at least one subchannel boundary that does not overlap with the first or second channel boundary. A typical device includes a station (STA), the STA including: a processor, and a transmit / receive unit, which is configured to: transmit control information including a subchannel SIG field for indicating a STA identity via an uplink, receive a trigger frame for indicating one or more subchannels that can be obtained from multiple subchannels, determine one or more subchannels to be acquired, and use the acquired one or more subchannels and transmit data via an uplink.

[0004] Another typical apparatus may include an access point (AP) configured to allocate subchannels of a physical channel for uplink communication of a station (STA). The physical channel may include a set of resources within a first and a second channel boundary, whereby the physical channel may include a plurality of subchannels, each of which may include a subset of physical channel resources and may have at least one subchannel boundary that does not coincide with the first or second channel boundary. The AP may include a transmit / receive unit configured to: receive control information including a subchannel SIG field indicating an identity of the station (STA) via an uplink, transmit a trigger frame to the STA indicating one or more subchannels that may be obtained from the plurality of subchannels, and use the obtained one or more subchannels and receive data via an uplink.

[0005] A typical method may be implemented by a station (STA) that uses at least one subchannel of a physical channel for uplink communication. The typical method may include: transmitting control information including a subchannel SIG field indicating an identity of the STA via an uplink, receiving a trigger frame indicating one or more subchannels that can be obtained from a plurality of subchannels, determining one or more subchannels to be obtained, and using the obtained one or more subchannels and transmitting data via an uplink.

[0006] Another typical method may be implemented by an access point (AP) that allocates a subchannel of a physical channel for uplink communication of a station (STA). The typical method may include: receiving control information including a subchannel SIG field indicating an identity of the station (STA) via an uplink, transmitting a trigger frame indicating one or more subchannels that can be obtained from a plurality of subchannels to the STA, using the obtained one or more subchannels and receiving data via an uplink.

[0007] Another typical apparatus includes a station (STA) configured to use at least one subchannel of a physical channel for uplink communication. The STA may include: a processor configured to: obtain information about at least one neighboring STA, and a transmitting / receiving unit configured to: transmit information about the at least one neighboring STA, and receive (1) a group identity of a group including the STA, and (2) information indicating one or more subchannels among a plurality of subchannels allocated to the STA.

[0008] Another typical apparatus may include an access point (AP) configured to allocate subchannels of a physical channel to a first STA among a plurality of stations (STAs) and one or more other STAs among the plurality of STAs. The AP may include: a transmit / receive unit configured to: for each corresponding STA among one or more STAs among the plurality of STAs, receive information including one or more neighboring STAs of the corresponding STA, and a processor configured to: assign a group identity to and allocate subchannels of a physical channel to a first STA and one or more other STAs that are group members of a multi-user group based on the received report. The transmit / receive unit may be configured to transmit at least (1) a group identity and (2) allocation information associated with one or more subchannels to the first STA and the one or more other STAs that are group members of the multi-user group.

[0009] Another typical method may be implemented by a station (STA) for grouping a station into a multi-user group using at least one subchannel of a physical channel. The physical channel may include a resource set associated with a plurality of subchannels, wherein each subchannel may include a subset of physical channel resources. The typical method may include: the STA obtaining information related to at least one neighboring STA, the STA transmitting the information related to the at least one neighboring STA to an AP, and the STA receiving: (1) a group identity of a group including the STA, and (2) information indicating one or more subchannels of a plurality of subchannels allocated to the STA.

[0010] Another typical method may be implemented by an access point (AP) that allocates subchannels of a physical channel to a first STA among a plurality of stations (STAs) and one or more other STAs among the plurality of STAs. The typical method may include: for each corresponding STA among one or more STAs among the plurality of STAs, receiving information including one or more neighboring STAs of the corresponding STA, assigning a group identifier to and allocating subchannels of a physical channel to a first STA and one or more other STAs that are group members of a multi-user group based on the received report, and transmitting (1) a group identifier and (2) allocation information associated with one or more subchannels to at least the first STA and the one or more other STAs that are group members of the multi-user group. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] A more detailed understanding can be obtained from the following detailed description section given by way of example in conjunction with the accompanying drawings attached hereto. As with the detailed description section, the figures in the drawings are examples. As such, the drawings and detailed description section should not be considered limiting, and other equally effective examples are also feasible and possible. In addition, the same reference numerals in the drawings indicate the same elements, and among them:

[0012] Figure 1 is a system diagram of an example communication system in which one or more disclosed embodiments may be implemented;

[0013] Figure 2 Yes, you can Figure 1 A system diagram of an example wireless transmit / receive unit (WTRU) used within the communication system shown;

[0014] Figure 3 It shows that it can be Figure 1 A system diagram of an example radio access network and another example core network used within the communication system shown;

[0015] Figure 4 It shows that it can be Figure 1 A system diagram of another exemplary radio access network and another exemplary core network for use within the illustrated communication system;

[0016] Figure 5 It shows that it can be Figure 1 A system diagram of another exemplary radio access network and another exemplary core network for use within the illustrated communication system;

[0017] Figure 6 is a system diagram showing an example station (STA) and an example access point (AP);

[0018] Figure 7 is a diagram showing the operation of Enhanced Distributed Channel Access (EDCA);

[0019] Figure 8 is a diagram showing the operation of energy detection clear channel assessment (CCA);

[0020] Fig. 9 is a diagram showing reduced frequency reuse for carrier sense multiple access (CSMA) operation;

[0021] Fig.10 is a diagram showing a typical neighbor report frame;

[0022] Fig.11 is a diagram showing a typical discovery frame;

[0023] Fig.12 is a diagram showing the operation of sub-channelized CSMA;

[0024] Fig.13 is a diagram showing CSMA operation with sub-channelization with dual triggering;

[0025] Fig.14 is a diagram showing slotted sub-channelized CSMA operation;

[0026] Fig.15 is a diagram showing CSMA operation with time slot sub-channelization with dual triggering;

[0027] Fig.16 is a flow chart illustrating a method for performing sub-channelized CSMA operation; and

[0028] Fig.17 is a flow chart illustrating a method for performing sub-channelized CSMA operation with dual triggering. DETAILED DESCRIPTION

[0029] Illustrative embodiments will now be described in detail with reference to the accompanying drawings. However, although the present invention is described in conjunction with typical embodiments, it is not limited thereto, and it should be understood that other embodiments may be used without departing from the present invention, and the described embodiments may also be modified and supplemented to perform the same functions of the present invention.

[0030] Although a wireless network architecture is used below to generally illustrate exemplary embodiments, any number of different networks may be used, including, by way of example, networks having wired components and / or wireless components.

[0031] Figure 1 1 is a diagram showing 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, broadcast, etc. to multiple wireless users. The communication system 100 allows multiple wireless users to access such content by sharing system resources including wireless bandwidth. As an example, the communication system 100 may use 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), and single carrier FDMA (SC-FDMA), etc.

[0032] like Figure 1 As shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 103 / 104 / 105, a core network 106 / 107 / 109, a public switched telephone network (PSTN) 108, the Internet 110 and other networks 112, however it should be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network components. Each WTRU 102a, 102b, 102c, 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” and / or “STAs” and may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile subscriber units, pagers, cellular phones, personal digital assistants (PDAs), smart phones, laptops, netbooks, personal computers, wireless sensors, consumer electronic devices, etc. The WTRUs 102a, 102b, 102c, 102d are also interchangeably referred to as UEs.

[0033] The communication system 100 may also include a base station 114a and / or a base station 114b. Each base station 114a, 114b may be any type of device configured to facilitate access to one or more communication networks, such as the core network 106 / 107 / 109, the Internet 110, and / or other networks 112, by wirelessly interfacing with at least one of the WTRUs 102a, 102b, 102c, 102d. For example, the base stations 114a, 114b may be base transceiver stations (BTS), node-Bs, e-node-Bs, home node-Bs, home e-node-Bs, site controllers, access points (APs), wireless routers, and the like. Although each base station 114a, 114b is depicted as a single component, it should be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network components.

[0034] The base station 114a may be part of the RAN 103 / 104 / 105, and the RAN may also include other base stations and / or network components (not shown), such as a base station controller (BSC), a radio network controller (RNC), and relay nodes, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals within a specific geographic area called a cell (not shown). The 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., each transceiver corresponds to a sector of the cell. In another embodiment, the base station 114a may use MIMO technology, whereby multiple transceivers may be used for each sector of the cell.

[0035] The base stations 114a, 114b may communicate with one or more WTRUs 102a, 102b, 102c, 102d via an air interface 115 / 116 / 117, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 115 / 116 / 117 may be established using any suitable radio access technology (RAT).

[0036] More specifically, as described above, the communication system 100 may be a multiple access system and may use one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, and SC-FDMA, among others. For example, the base station 114a in the RAN 103 / 104 / 105 and the WTRUs 102a, 102b, 102c, 102d may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), and the technology may use Wideband CDMA (WCDMA) to establish the air interface 115 / 116 / 117. 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 ​​UL Packet Access (HSUPA).

[0037] In another embodiment, the base station 114a and the WTRUs 102a, 102b, 102c, 102d may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 115 / 116 / 117 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A).

[0038] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio access technologies such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (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), and the like.

[0039] As an example, Figure 1The base station 114b in the example may be a wireless router, a Home NodeB, a Home eNodeB, or an access point (AP), and may use any appropriate RAT to facilitate wireless connectivity in a local area, such as a business location, a residence, a vehicle, a campus, and the like. In one embodiment, the base station 114b and the WTRUs 102c and 102d may establish a wireless local area network (WLAN) by implementing a radio technology such as IEEE802.11. In another embodiment, the base station 114b and the WTRUs 102c and 102d may establish a wireless personal area network (WPAN) by implementing a radio technology such as IEEE 802.15. In yet another embodiment, the base station 114b and the WTRUs 102c and 102d may establish a picocell or a femtocell by using a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.). Figure 1 As shown, the base station 114b may be directly connected to the Internet 110. Thus, the base station 114b does not need to access the Internet 110 via the core network 106 / 107 / 109.

[0040] The RAN 103 / 104 / 105 may be in communication with a core network 106 / 107 / 109, which may be any type of network configured to provide voice, data, applications, and / or voice over Internet Protocol (VoIP) services to one or more WTRUs 102a, 102b, 102c, 102d. For example, the core network 106 / 107 / 109 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions such as user authentication. Although in Figure 1 Not shown, however, it will be appreciated that the RAN 103 / 104 / 105 and / or the core network 106 / 107 / 109 may be in direct or indirect communication with other RANs that employ the same RAT or a different RAT as the RAN 103 / 104 / 105. For example, in addition to being connected to the RAN 103 / 104 / 105 employing E-UTRA radio technology, the core network 106 / 107 / 109 may also be in communication with another RAN (not shown) employing GSM, UMTS, CDMA 2000, WiMAX, or WiFi radio technology.

[0041] The core network 106 / 107 / 109 may also act 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 that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer network devices that use a common communication protocol, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and / or the Internet Protocol (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 networks 112 may include another core network connected to one or more RANs, where the one or more RANs may use the same RAT or a different RAT as the RAN 103 / 104 / 105.

[0042] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication 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). Figure 1 The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0043] Figure 2 is a system diagram showing an example WTRU 102. Figure 2 As shown, the WTRU 102 may include a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a numeric keypad 126, a display / touchpad 128, a non-removable memory 130, a removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It should be appreciated that the WTRU 102 may include any sub-combination of the foregoing components while remaining consistent with an embodiment.

[0044] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of 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) circuit, any other type of integrated circuit (IC), a state machine, and the like. 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. Although Figure 2 The processor 118 and the transceiver 120 are depicted as separate components, however it should be appreciated that the processor 118 and the transceiver 120 may be integrated into one electronic component or chip.

[0045] The transmit / receive component 122 may be configured to transmit or receive signals to or from a base station (e.g., base station 114a) via an air interface 115 / 116 / 117. For example, in one embodiment, the transmit / receive component 122 may be an antenna configured to transmit and / or receive RF signals. In another embodiment, as an example, the transmit / receive component 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals. In yet another embodiment, the transmit / receive component 122 may be configured to transmit and / or receive RF and light signals. It should be appreciated that the transmit / receive component 122 may be configured to transmit and / or receive any combination of wireless signals.

[0046] Although in Figure 2 102 as a single component, however, the WTRU 102 may include any number of transmit / receive components 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive components 122 (e.g., multiple antennas) for transmitting and receiving radio signals via the air interface 115 / 116 / 117.

[0047] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive component 122 and to demodulate signals received by the transmit / receive component 122. As described above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers that allow the WTRU 102 to communicate via multiple RATs, such as UTRA and IEEE 802.11.

[0048] The processor 118 of the WTRU 102 may be coupled to a speaker / microphone 124, a numeric 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), and may receive user input data from these components. The processor 118 may also output user data to the speaker / microphone 124, the numeric keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store information in any suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0049] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power for use by 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 (Ni-Cd), nickel-zinc (Ni-Zn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0050] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) related to the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) via the air interface 115 / 116 / 117 and / or determine its location based on the timing of signals received from two or more nearby base stations. It should be appreciated that the WTRU 102 may acquire location information using any suitable positioning method while remaining consistent with an embodiment.

[0051] 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 electronic compass, a satellite transceiver, a digital camera (for photos and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, modules, FM radio units, digital music players, media players, video game console modules, Internet browsers, and more.

[0052] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all signals (e.g., associated with UL (e.g., for transmission) and downlink (e.g., for reception)) may occur and / or be performed simultaneously. The full-duplex radio may include an interference management unit 139 that reduces or substantially eliminates self-interference by means of hardware (e.g., chokes) or by signal processing with a processor (e.g., a separate processor (not shown) or with the processor 118).

[0053] Figure 3 1 is a system diagram showing the RAN 103 and the core network 106 according to another embodiment. As described above, the RAN 103 may employ a UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 115. In addition, the RAN 103 may also be in communication with the core network 106. Figure 3 As shown, the RAN 103 may include Node-Bs 140a, 140b, 140c, each of which may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c via the air interface 115. Each of the Node-Bs 140a, 140b, 140c may be associated with a particular cell (not shown) within the RAN 103. The RAN 103 may also include RNCs 142a, 142b. It will be appreciated that the RAN 103 may include any number of Node-Bs and RNCs while remaining consistent with the embodiment.

[0054] like Figure 3As shown, Node B 140a, 140b can communicate with RNC 142a. In addition, Node B 140c can communicate with RNC 142b. Node B 140a, 140b, 140c can communicate with corresponding RNC 142a, 142b via Iub interface. RNC 142a, 142b can communicate with each other via Iur interface. Each RNC 142a, 142b can be configured to control the corresponding Node B 140a, 140b, 140c connected thereto. In addition, each RNC 142a, 142b can be configured to perform or support other functions, such as outer loop power control, load control, admission control, packet scheduling, switching control, macro diversity, security functions and data encryption, etc.

[0055] Figure 3 The illustrated core network 106 may include a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS node switching center (SGSN) 148, and / or a gateway GPRS support node (GGSN) 150. Although each of the aforementioned components are described as being part of the core network 106, it should be understood that entities other than the core network operator may also own and / or operate any of these components.

[0056] The RNC 142a in the RAN 103 may be connected to the MSC 146 in the core network 106 via an IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and the MGW 144 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 land-line communications devices.

[0057] The RNC 142a in the RAN 103 may also be connected to the SGSN 148 in the core network 106 via an IuPS interface. The SGSN 148 may be connected to the GGSN 150. The SGSN 148 and the GGSN 150 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.

[0058] As described above, the core network 106 may also be connected to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0059] Figure 41 is a system diagram showing the RAN 104 and the core network 106 according to one embodiment. As described above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. In addition, the RAN 104 may also be in communication with the core network 106.

[0060] The RAN 104 may include eNode-Bs 160a, 160b, 160c, however it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. Each of the eNode-Bs 160a, 160b, 160c may include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, for example, the eNode-B 160a may use multiple antennas to transmit wireless signals to, and / or receive wireless signals from, the WTRU 102a.

[0061] Each eNodeB 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, user scheduling in the uplink and / or downlink, and the like. Figure 4 As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0062] Figure 4 The illustrated core network 106 may include a mobility management gateway (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. Although each of the foregoing components are described as being part of the core network 106, it should be appreciated that entities other than the core network operator may also own and / or operate any of these components.

[0063] The MME 162 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface and may serve 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 an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may also provide a control plane function to facilitate handover between the RAN 104 and other RANs (not shown) that employ other radio technologies such as GSM and / or WCDMA.

[0064] The serving gateway 164 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The serving gateway 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The serving gateway 164 may also perform other functions, such as anchoring the user plane during inter-eNode-B handovers, triggering paging when downlink data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0065] The serving gateway 164 may also be connected to the PDN gateway 166, which 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.

[0066] The core network 106 may facilitate communications with other networks. For example, the core network 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 land-line communications devices. As an example, the core network 106 may include or communicate with an IP gateway, such as an IP Multimedia Subsystem (IMS) server, which serves as an interface between the core network 106 and the PSTN 108. The core network 106 may also 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.

[0067] Figure 5 1 is a system diagram showing the RAN 105 and the core network 109 according to one embodiment. The RAN 105 may be an access service network (ASN) that communicates with the WTRUs 102a, 102b, 102c over the air interface 117 using IEEE 802.16 radio technology. As discussed further below, communication links between the different functional entities of the WTRUs 102a, 102b, 102c, the RAN 105, and the core network 109 may be defined as reference points.

[0068] like Figure 5As shown, the RAN 105 may include base stations 180a, 180b, 180c and an ASN gateway 182, however it should be appreciated that the RAN 105 may include any number of base stations and ASN gateways while remaining consistent with the embodiments. Each base station 180a, 180b, 180c may be associated with a particular cell (not shown) in the RAN 105, and each base station may include one or more transceivers to communicate with the WTRUs 102a, 102b, 102c over the air interface 117. In one embodiment, the base stations 180a, 180b, 180c may implement MIMO technology. Thus, for example, the base station 180a may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a. The base stations 180a, 180b, 180c may also provide mobility management functions, such as handover triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, and the like. The ASN gateway 182 may act as a traffic aggregation point and may be responsible for implementing paging, subscriber profile caching, routing to the core network 109, and the like.

[0069] The air interface 117 between the WTRUs 102a, 102b, 102c and the RAN 105 may be defined as an R1 reference point implementing the IEEE 802.16 specification. In addition, each of the WTRUs 102a, 102b, 102c may establish a logical interface (not shown) with the core network 109. The logical interface between the WTRUs 102a, 102b, 102c and the core network 109 may be defined as an R2 reference point, which may be used for authentication, authorization, IP host configuration management, and / or mobility management.

[0070] The communication link between each base station 180a, 180b, 180c may be defined as an R8 reference point, which includes protocols for facilitating WTRU handovers and data transfer between base stations. The communication link between the base stations 180a, 180b, 180c and the ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include protocols for facilitating mobility management based on mobility events associated with each WTRU 102a, 102b, 180c.

[0071] like Figure 5As shown, the RAN 105 may be connected to a core network 109. The communication link between the RAN 105 and the core network 109 may be defined as an R3 reference point, which, as an example, includes protocols for facilitating data transfer and mobility management capabilities. The core network 109 may include a mobile IP home agent (MIP-HA) 184, an authentication authorization accounting (AAA) server 186, and a gateway 188. Although each of the aforementioned components are described as being part of the core network 109, it should be appreciated that an entity other than the core network operator may own and / or operate any of these components.

[0072] The MIP-HA 184 may be responsible for implementing IP address management and may enable the WTRUs 102a, 102b, 102c to roam between different ASNs and / or different core networks. The MIP-HA 184 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. The AAA server 186 may be responsible for implementing user authentication and supporting user services. The gateway 188 may facilitate interworking with other networks. For example, the gateway 188 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 landline communications devices. In addition, the gateway 188 may also provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks that are owned and / or operated by other service providers.

[0073] Although in Figure 5 Not shown, however, it should be appreciated that the RAN 105 may also be connected to other ASNs, and other RANs (e.g., RAN 103 and / or 104) and / or the core network 109 may be connected to other core networks (e.g., core networks 106 and / or 107). The communication link between the RAN 105 and the other ASNs may be defined as an R4 reference point, which may include protocols for coordinating the mobility of the WTRUs 102a, 102b, 102c between the RAN 105 and the other ASNs. The communication link between the core network 109 and the other core networks may be defined as an R5 reference point (not shown), which may include protocols for facilitating interworking between a home core network and a visited core network.

[0074] Although in Figure 1-5The WTRU is described as a wireless terminal, however it should be appreciated that in certain typical embodiments such a terminal may also use a (temporary or permanent) wired communication interface to interface with a communication network.

[0075] In a typical embodiment, the other network 112 may be a WLAN.

[0076] A WLAN using an infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more STAs associated with the AP. The AP may have an entry or interface connected to a distributed system (DS) or other type of wired / wireless network for transporting traffic entering and / or leaving the BSS. Traffic from outside the BSS to the STA may arrive through the AP and may be delivered to the STA. Traffic from the STA to a destination outside the BSS may be sent to the AP and thereby delivered to the corresponding destination. Traffic between STAs inside the BSS may be sent through the AP, for example, the source STA may send traffic to the AP, and the AP may deliver traffic to the destination STA. Traffic between STAs inside the BSS may be considered and / or referred to as point-to-point traffic. Point-to-point traffic may be sent using a direct link setup (DLS) between the source and destination STAs (e.g., directly therebetween). In certain typical 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 (eg, all STAs) within or using the IBSS may communicate directly with each other. This IBSS communication mode is sometimes referred to as an "ad hoc" communication mode.

[0077] When using the 802.11ac infrastructure mode of operation or a similar mode of operation, the AP may transmit beacons on a fixed channel (e.g., a primary channel). The primary channel may have a fixed width (e.g., a bandwidth of 20 MHz) or a width that is dynamically set by means of signaling. The primary channel may be a working channel of the BSS and may be used by the STA to establish a connection with the AP. In certain typical embodiments, carrier sense multiple access with collision avoidance (CSMA / CA) may be implemented, such as in an 802.11 system. For CSMA / CA, the STA (e.g., each STA) and / or the AP may sense the primary channel. If a particular STA senses / detects and / or determines that the primary channel is busy, the particular STA may back off. In a given BSS, only one STA (e.g., only one station) may transmit at any given time.

[0078] A high throughput (HT) STA may communicate using a 40 MHz bandwidth channel, for example, by combining a 20 MHz primary channel with an adjacent 20 MHz channel and thereby forming a 40 MHz continuous channel.

[0079] Very high throughput (VHT) STA can support 20MHz, 40MHz, 80MHz and / or 160MHz channels. 40MHz and / or 80MHz channels can be formed by combining continuous 20MHz channels. 160MHz channels can be formed by combining eight continuous 20MHz channels or by combining two discontinuous 80MHz channels, which can be referred to as 80+80 configuration. For the 80+80 configuration, data can be passed through a segment parser after channel coding, wherein the segment parser divides the data into two streams. Inverse fast Fourier transform (IFFT) processing and time domain processing can be performed separately on each stream. These streams can be mapped to two 80MHz channels, and the data can be transmitted by the STA performing the transmission. At the receiver of the STA performing the reception, the above operations for the 80+80 configuration can be reversed, and the combined data can be sent to the medium access control (MAC) layer.

[0080] 802.11af and 802.1ah support sub-1GHz operating modes. Compared with the channel operating bandwidth and carrier used in 802.11n and 802.11ac, 802.11af and 802.11ah use reduced channel operating bandwidth and carrier. 802.11af supports 5MHz, 10MHz and 20MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz and 16MHz bandwidths using non-TVWS spectrum. According to a typical embodiment, 802.11ah can support meter type control / machine type communication (MTC), such as MTC devices in macro coverage areas. MTC devices can have certain capabilities, such as limited capabilities including providing support for (e.g., only supporting) certain and / or restricted bandwidths. MTC devices can include a battery, and the battery life of the battery is higher than a threshold (e.g., for maintaining a very long battery life).

[0081] For WLAN systems that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah), these systems include a channel designated as a primary channel. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a specific STA that supports the minimum bandwidth operating mode among all STAs operating in the BSS. In an example regarding 802.11ah, the width of the primary channel may be 1 MHz, thereby accommodating STAs (such as MTC type devices) that support (e.g., only support) a 1 MHz mode, 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) settings may depend on the state of the primary channel. If the primary channel is busy because, for example, a STA (supporting only 1 MHz operation) is transmitting to the AP, the entire available frequency band is considered busy even though most of the frequency band remains idle and available.

[0082] In the United States, the available frequency band for 802.11ah is 902MHz to 928MHz. In South Korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. Depending on the country code, the total bandwidth available for 802.11ah is 6MHz to 26MHz.

[0083] Figure 6 is a system diagram showing an example station (STA) 601 and an example access point (AP) 602 that can communicate via a wired and / or wireless connection (eg, an RF connection). Figure 6As shown, STA 601 may include a processor 615, a transceiver 613, a transmitting / receiving component 603, a speaker / microphone 605, a numeric keypad 607, a display / touch pad 609, a non-removable memory 611, a removable memory 617, a power supply 619, a global positioning system (GPS) chipset 621, other peripheral devices 623, and an interface management unit 625, etc. It should be understood that while remaining consistent with the embodiment, the station STA may also include any sub-combination of the foregoing components. AP 602 may include a processor 616, a transceiver 614, a transmitting / receiving component 604, a speaker / microphone 606, a numeric keypad 608, a display / touch pad 610, a non-removable memory 612, a removable memory 618, a power supply 620, a global positioning system (GPS) chipset 622, other peripheral devices 624, and an interface management unit 626, etc. It should be understood that while remaining consistent with the embodiment, the AP 602 may include any sub-combination of the foregoing components. In addition, the components included in the AP 602 identified above may operate in a similar manner as similarly identified components included in the STA 601. The description of the components included in the AP 602 is the same and / or similar to the components included in the STA 601, and for the sake of brevity, a separate description of the components included in the AP 602 will not be provided below.

[0084] The processor 615 can be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of 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) circuit, any other type of integrated circuit (IC), a state machine, and the like. The processor 615 can perform signal encoding, data processing, power control, input / output processing, and / or any other functions that enable the STA 601 to operate in a wireless environment. The processor 615 can be coupled to the transceiver 613, and the transceiver 613 can be coupled to the transmit / receive component 603. Although Figure 6 The processor 615 and the transceiver 613 are depicted as separate components, however it should be appreciated that the processor 615 and the transceiver 613 may be integrated into one electronic component or chip.

[0085] The transmit / receive component 603 may be configured to transmit or receive signals to or from a base station (e.g., AP 602) via an air interface 627. For example, in one embodiment, the transmit / receive component 603 may be an antenna configured to transmit and / or receive RF signals. In another embodiment, as an example, the transmit / receive component 603 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals. In yet another embodiment, the transmit / receive component 603 may be configured to transmit and / or receive RF and light signals. It should be appreciated that the transmit / receive component 603 may be configured to transmit and / or receive any combination of wireless signals.

[0086] Although in Figure 6 601 is described as a single component, but the STA 601 may include any number of transmit / receive components 603. More specifically, the STA 601 may use MIMO technology. Therefore, in one embodiment, the STA 601 may include two or more transmit / receive components 603 (e.g., multiple antennas) that transmit and receive radio signals via the air interface 627.

[0087] The transceiver 613 may be configured to modulate the signal to be transmitted by the transmit / receive component 603 and demodulate the signal received by the transmit / receive component 603. As described above, the STA 601 may have multi-mode capabilities. Thus, the transceiver 603 may include multiple transceivers that allow the STA 601 to communicate via multiple RATs (e.g., UTRA and IEEE 802.11).

[0088] The processor 615 of the STA 601 may be coupled to the speaker / microphone 605, the numeric keypad 607, and / or the display / touchpad 609 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit), and may receive user input data from these components. The processor 615 may also output user data to the speaker / microphone 605, the numeric keypad 607, and / or the display / touchpad 609. In addition, the processor 615 may access information from any appropriate memory (e.g., a non-removable memory 611 and / or a removable memory 617), and store information in these memories. The non-removable memory 611 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 617 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 615 may access information from and store data in memories that are not actually located in the STA 601, and as an example, such memories may be located in a server or a home computer (not shown).

[0089] The processor 615 may receive power from a power source 619 and may be configured to distribute and / or control power to other components in the STA 601. The power source 619 may be any suitable device for powering the STA 601. For example, the power source 619 may include one or more dry cell batteries (e.g., nickel-cadmium (Ni-Cd), nickel-zinc (Ni-Zn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0090] The processor 615 may also be coupled to a GPS chipset 621, which may be configured to provide location information (e.g., longitude and latitude) related to the current location of the STA 601. In addition to or in lieu of the information from the GPS chipset 621, the STA 601 may receive location information from an AP (e.g., AP 602) via an air interface 627, and / or determine its location based on the timing of signals received from two or more nearby base stations. It should be appreciated that the STA 601 may obtain location information by any suitable positioning method while remaining consistent with the embodiment.

[0091] The processor 615 may also be coupled to other peripherals 623, 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 623 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, modules, FM radio units, digital music players, media players, video game console modules, Internet browsers, and more.

[0092] The STA 601 may include a full-duplex radio for which transmission and reception of some or all signals (e.g., associated with UL (e.g., for transmission) and downlink (e.g., for reception)) may occur and / or be performed simultaneously. The full-duplex radio may include an interference management unit 625 that reduces or substantially eliminates self-interference by means of hardware (e.g., chokes) or by means of signal processing by a processor (e.g., a separate processor (not shown) or by means of the processor 615). Although the WTRU 102, STA 601, and AP 602 are described separately, it is contemplated that any combination of components, capabilities, functions, and / or operations of the WTRU 102, STA 601, and AP 602 may be incorporated into a multi-mode device.

[0093] Channel access scheme in 802.11

[0094] Figure 7 is a diagram showing a typical enhanced distributed channel access (EDCA) operation.

[0095] The channel access scheme may include EDCA operation and may be an extension of the basic distributed coordination function (DCF). EDCA operation may support prioritized quality of service (QoS) and contention-based access for a communication medium (e.g., a radio frequency (RF) channel) channel access scheme. Figure 7 One or more EDCA operations (eg, in 802.11n) are shown in FIG.

[0096] The channel access scheme 700 (e.g., in 802.11) may be a point coordination function (PCF) that may support time-critical services using contention-free channel access, where the AP polls STAs (e.g., each STA) in the BSS. After a medium busy period 701 in which the medium is used by one or more STAs / APs, the AP may send a polling message after waiting for a PCF interframe space (IFS). If a client (e.g., a STA) has no information to send, the client may transmit an empty data frame. In addition, after the medium busy period 701, a QoS / non-QoS AP / STA 710 may perform data access. For example, after waiting for a short IFS (SIFS), the QoS / non-QoS AP / STA may perform a burst and response access (703), such as by transmitting an acknowledgement (ACK), a block acknowledgement (BA), and / or a clear to send (CTS), etc. The QoS / non-QoS AP / STA 710 may also perform a priority access 704 after waiting for a PCF IFS (PIFS), such as by transmitting a beacon. The QoS / non-QoS AP / STA 710 may perform legacy data / management access 705 after the DCF IFS (DIFS) and the backoff period. The QoS AP / STA 711 may perform access based on different priorities and / or QoS and / or access categories (AC) of different data types. For example, the QoS AP / STA 711 may perform a voice transmission opportunity (TXOP) access 706 after waiting for the arbitration IFS (AIFS) and the AC backoff (AC_VO) for voice data in order to transmit voice data. The QoS AP / STA 711 may perform a video TXOP access 707 after waiting for the arbitration IFS (AIFS) and the AC backoff (AC_VI) for video data in order to transmit video data. The QoS AP / STA 711 may perform a best-effort (BE) TXOP access 708 after waiting for the arbitration IFS (AIFS) and the AC backoff (AC_BE) for BE data in order to transmit BE data. QoS AP / STA 711 may perform background (BK) TXOP access 709 to transmit BK data after waiting for arbitration IFS (AIFS) and AC fallback (AC_BK) for BK data. PCF channel access scheme is deterministic, fair and / or efficient for low duty cycle and / or heavy / burst traffic. Hybrid coordination function (HCF) controlled channel access (HCCA) may be an enhancement to PCF, where the AP may poll the STA during one or both of the contention period (CP) and / or the contention-free period (CFP). The AP may transmit multiple frames by means of one poll (e.g., by means of one instance of polling the STA).

[0097] High-efficiency WLAN (HEW)

[0098] As an example, in high-density scenarios (e.g., in 2.4 GHz and / or 5 GHz bands), HEW can enhance the QoS user experience. Potential applications for HEW can include usage scenarios (e.g., data delivery for stadium events), high user density scenarios (e.g., train stations), and / or enterprise / retail environments, etc. Other usage scenarios can be based on the growing reliance on video and / or media content delivery, wireless services for medical applications, and / or other data-rich services.

[0099] OFDMA in 802.11ax

[0100] As an example, in 802.11 (which may also be referred to as a Wi-Fi system, such as 802.11a / g / n / ac / ah), a transmission and / or reception process may use the entire allocated bandwidth to perform transmission and / or reception. In certain typical embodiments, orthogonal frequency division multiple access (OFDMA) may be implemented in WLAN to solve the inefficiency caused by resource scheduling that allocates the entire allocated bandwidth (e.g., the entire channel) to a single user. If OFDMA is directly applied to WiFi, backward compatibility issues may be introduced.

[0101] Cooperative orthogonal block-based resource allocation (COBRA) can address WiFi backward compatibility by introducing OFDMA methods and / or operations, and / or can address the inefficiencies caused by channel-based resource scheduling. For example, COBRA can enable transmission on multiple small frequency-time resource units. Multiple users can be assigned to non-overlapping frequency-time resource units and can perform transmission and / or reception at the same time. A subchannel can generally be defined as a basic frequency resource unit (e.g., time / frequency resource) that can be allocated to a STA by an AP. For example, considering backward compatibility with 802.11n and / or 802.11ac, etc., a subchannel can be defined as a 20MHz channel. It is conceivable that the bandwidth of these subchannels can be less than 20MHz, or it can be limited to having a bandwidth of 20MHz.

[0102] Techniques in COBRA may include multi-carrier modulation, filtering, time domain, frequency domain, spatial domain and / or polarization domain as the basis for transmission and / or coding schemes. The COBRA scheme may be implemented using one or more of OFDMA sub-channelization, single carrier frequency division multiple access (SC-FDMA) sub-channelization and / or filter bank multi-carrier sub-channelization. According to one embodiment, to enable COBRA transmission, any one or more of the following features may be implemented: (1) coverage extension method; (2) user grouping method; (3) channel access method; (4) low overhead preamble design; (5) beamforming and / or sounding method; (6) frequency and / or timing synchronization method. And / or (7) link adaptation method.

[0103] Frequency and / or time synchronization algorithms for COBRA may be used. For example, in addition to the method implemented using COBRA, multi-user concurrent channel access (MU-PCA) and single-user concurrent channel access (SU-PCA) schemes may also include several methods.

[0104] As an example, MU / SU-PCA may include a multi-user / single-user parallel channel access method using transmission / reception operations with symmetric bandwidth, which may provide any of the following: (1) downlink parallel channel access for multi-user / single user; (2) uplink parallel channel access for multi-user / single user; (3) combined downlink and uplink parallel channel access for multi-user / single user; (4) a design that supports unequal MCS and unequal transmit power for SU-PCA and / or COBRA; (5) a PHY design and / or process that supports multi-user / single-user parallel channel access using transmission / reception with symmetric bandwidth; and / or (6) a hybrid MAC / physical (PHY) MU-PCA.

[0105] As another example, MU-PCA may include a MU-SU-PCA transmission / reception method for using asymmetric bandwidth, wherein the method may provide MAC layer design and procedures for downlink, uplink, and combined uplink and downlink for multi-user / single-user parallel channel access using asymmetric bandwidth; and / or may provide a PHY layer design and procedures for supporting multi-user / single-user parallel channel access using transmission / reception with asymmetric bandwidth. Additional techniques may also be implemented, such as a scalable channel usage method that allows STAs to scale their transmission bandwidth based on channel or traffic availability.

[0106] Fixed and dynamic CCA adaptation

[0107] Figure 8is a diagram showing a typical energy detection clear channel assessment (CCA) operation.

[0108] refer to Figure 8 , STA 601 and / or AP 602 may use a CCA threshold to determine whether a channel is available for use. For example, in operation 801, STA 601 and / or AP 602 may measure energy (which may be referred to as transmission energy (Et)) in a channel (e.g., a transmission channel or a transmission bandwidth (BW)) in order to decide (e.g., determine) whether the channel can be used for transmission based on whether the energy in the channel exceeds a CCA threshold. The CCA threshold may be fixed or dynamic. In operation 802, STA 601 and / or AP 602 may determine whether Et measured in operation 801 exceeds a CCA threshold. In operation 803, if Et exceeds the CCA threshold, then STA 601 and / or AP 602 may determine that the medium is busy, or in operation 804, if Et does not exceed the CCA threshold, then it may be determined that the medium is idle.

[0109] Typical Mobile Slotted Aloha Protocol (MS-Aloha)

[0110] MS-Aloha is expected to be a hybrid solution between scheduled and unscheduled MAC packets and can be categorized between packet-based and contention-free MAC approaches. MS-Aloha does not contain any reserved parts separate from the data exchange.

[0111] For example, in a vehicle network, MS-Aloha may be used during the connection and establishment phase of a phone call (e.g., phases including reservation request, confirmation, data exchange, and / or teardown, etc.). MS-Aloha may be applied and / or used based on one or more of the following conditions: (1) the reception signal is obstructed by hidden stations; (2) the device is difficult to manage due to high packet loss; (3) the device has mobility; and / or (4) the device has a time-varying channel, etc. MS-Aloha may be connection-oriented and may continuously refresh the reservation portion (e.g., each reservation portion) in conjunction with the STA performing the transmission in each period.

[0112] As an example, MS-Aloha can use a periodic frame structure, thereby including fixed-length time slots that can represent different resources to be allocated and / or used. The fixed-length time slots can be referred to as the "time slot" structure of the time slot. MS-Aloha can include absolute synchronization for Coordinated Universal Time (UTC). Any node can know the current position in the frame based on UTC, and can know this independently of the received frame. Absolute synchronization can prevent time misalignment, signal misalignment and / or clock cycles. In order to reduce propagation delays, MS-Aloha can include protection time. For example, the MS-Aloha frame considered by the receiver can float within the boundaries of the ideal time slot. The header of the MS-Aloha frame can be used to properly restore the beginning of each MS-Aloha frame.

[0113] A node (e.g., a WTRU and / or STA) attempting to reserve a slot may pick up an idle slot and may reserve the slot if the node performs a transmission in the current frame and continues to transmit in the next frame. The transmission may be an implicit reserved portion for the next frame. If a node uses a slot in a frame to perform a transmission, then the slot in the next frame will be reserved for the transmitting node and the node will use that slot. If a node does not use a slot in the current frame to perform a transmission, then the slot will not be used and the slot in the next frame may be used for other nodes.

[0114] By using OFDMA (e.g., in 802.11), techniques may be provided that enable scalable channel usage and / or improved spatial reuse, among other things. In certain exemplary embodiments, these techniques may enable legacy devices (e.g., WTRUs, APs, STAs) that are compatible with the 802.11 standard to improve their spatial reuse and implement sub-channel usage.

[0115] Fig. 9 is a diagram showing a reduced frequency reuse approach using OFDMA in conjunction with a legacy CCA procedure.

[0116] refer to Fig. 9 , which shows an example scenario. Fig. 9As shown, when using OFDMA and the existing standard CCA process, the network may suffer from reduced frequency reuse. In the legacy scenarios 1 and 2, the AP and / or STA of BSS-B are able to reuse the same 20 MHz spectrum to transmit or receive packets (e.g., 20 MHz physical layer convergence protocol (PLCP) protocol data unit (PPDU) 901) because neither the BSS-B AP nor the BSS-B STA can sense that the BSS-A AP uses the 20 MHz channel in the coverage area 903 of the BSS-A AP, and cannot sense that the BSS-A STA-1 uses the 20 MHz channel in the coverage area 904 of the BSS-A STA-1. In the UL-OFDMA scenario, BSS-A STA-1 and BSS-A STA-2 can transmit packets, such as 10 MHz PPDU 902, to the BSS-A AP, respectively. As shown Fig. 9 As shown, as an example, a 10 MHz PPDU 902 may be transmitted using an adjacent 10 MHz sub-channel. In this case, a BSS-B STA arranged in the coverage area 905 of BSS-A STA-2 will not be able to communicate with the BSS-B AP (e.g., transmit / receive packets to / from the BSS-B AP) because the BSS-BSTA may sense or detect ongoing communications performed by BSS-A STA-2 in the coverage area 905 of BSS-A STA-2, such as transmission of a 10 MHz PPDU 902 by BSS-A STA-2 via a 10 MHz sub-channel.

[0117] As an example, since the BSS-A AP schedules UL-OFDMA transmissions from two STAs that are not close to each other, and since the BSS-B STA adjacent to one of the BSS-A STAs is likely to determine whether the medium is busy / idle by following the legacy CCA procedure for sensing the 20 MHz channel as a whole, the BSS-B STA will not be able to transmit / receive packets.

[0118] In other words, in the uplink direction, although the BSS-B AP will receive the signal without any interference, the BSS-B STA may sense that the channel is busy and may not perform transmission. In the downlink direction, if Ready to Send (RTS) / Clear to Send (CTS) is used, there will be no transmission from the BSS-B AP, which may be because the BSS-B STA may not be able to successfully decode the RTS frame from the BSS-B AP, or because the BSS-B STA senses that the channel is busy and will not respond to the BSS-B AP using a CTS frame. If RTS / CTS is not used, the BSS-B AP can sense that the channel is idle and can transmit the signal. In this case, since half of the channels will encounter interference from the signal from BSS-A STA 2, the BSS-B STA will not be able to successfully decode the signal.

[0119] If BSS-A STA1 is power limited (e.g. in legacy scenarios), the frequency reuse process may be further reduced. When using uplink OFDMA, the power will have a small amount of scaling based on and / or associated with bandwidth (BW), and if Fig. 9 As shown, the two thick circles in the UL-OFDMA scenario are larger than the red circles in the legacy scenario. The larger circles may indicate that more neighboring BSS STAs are prohibited from transmitting due to interference from neighboring devices.

[0120] CSMA / CA with OFDMA

[0121] In order to use the OFDMA system for uplink transmission in WLAN, a set of operations may include using the AP as a resource scheduler and assignor for different STAs. At the beginning of uplink OFDMA transmission (e.g., at the beginning of each), the AP may send a trigger frame to the scheduled STAs. The trigger frame may inform which STA will transmit data and in which subchannel the STA will transmit data. If a trigger frame is transmitted at the beginning of each uplink OFDMA transmission, one or more of the following situations will be caused and / or resulted: (1) inefficient resource allocation may cause and / or result in a scenario in which the amount of data to be transmitted by STAs varies greatly, or different modulation and coding schemes (MCS) are used to perform transmissions due to changing channel quality (for example, STAs with small amounts of data must pad their transmissions with zeros to compensate for the packet transmission length; and / or (2) in scenarios in which the transmission data frames are very long, other STAs waiting to access the medium may cause traffic delays. By implementing a method for addressing the inefficient resource utilization caused by padding processing implemented for STAs with large differences in data amounts and channel access delays, CSMA / CA using OFDMA can be supported.

[0122] Method for alleviating reuse reduction during OFDMA-based transmission in a WLAN system

[0123] like Fig. 9 As shown, when using OFDMA and the existing standard CCA process, the network may suffer from the impairment of reduced frequency reuse.

[0124] This frequency reuse reduction can be mitigated by implementing and / or using methods, apparatus (e.g., STAs and APs), and systems. For example, a STA can send control and / or management frames to an AP associated with it, and can inform the AP associated with it of the overlapping BSS (OBSS) / color observed by the STA. This information enables the AP to schedule uplink (UL)-OFDMA to STAs that are geographically close to each other. For example, refer to Fig. 9 , BSS-A STA 1 can report its neighbor BSS as BSS-C. BSS-A STA 2 can report its neighbor BSS as BSS-B. With the information of the corresponding neighbor BSSs, the BSS-A AP can avoid scheduling these two STAs in the same UL-OFDMA transmission.

[0125] A STA may use passive and / or active processes to discover and / or report to its AP its neighboring STAs that are close in location. For example, a STA may passively and / or actively report neighboring STAs that are close in geographic location and / or neighbors that may receive a strong signal.

[0126] According to one embodiment, in a typical passive process, a STA may discover and / or report neighbors whose geographical locations (and / or working locations) are close to it according to any one or more of the following processes.

[0127] Upon receiving a packet, the STA may extract information from one or more of the following: a preamble, a MAC header, a frame body, and / or any portion of the received packet. The information extracted by the STA from the received packet may include one or more of the following: a MAC address of the transmitting STA and / or the receiving STA, a BSSID, a BSS color, an association ID (AID), a local AID (PAID), a group ID, and / or a received power of the packet (e.g., a received signal strength indicator (RSSI), a received channel power indicator (RCPI), and / or any other power metric).

[0128] The receiving STA may record the extracted information to memorize all transmitting STAs or a subset of the STAs directly adjacent to the receiving STA. For example, the receiving STA may record the received STA with a receiving power level exceeding the receiving power level RX thres In some examples, the receiving STA may record (e.g., only record) the transmitting STAs from the same BSS as the receiving STA. In different examples, the receiving STA may record (e.g., only record) the transmitting STAs from the same BSS as the receiving STA and whose packets are transmitted at a power level exceeding the received power level RX. thres The power level received by the STA performing the transmission.

[0129] Receive power level threshold RX thres It can be determined based on an absolute received power measurement. For example, if it is known that the STA performing the transmission is using a uniform transmit power, the uniform transmit power can be used to determine the RX thres In some cases (for example, when the STAs performing transmission use different channel widths to perform transmission), the receive power level threshold RX thres The power density may be used as an indication. In some embodiments, the receive power level threshold RX thres It can be adjusted for the actual transmission frequency bandwidth. Different transmission frequency bandwidths can be used, for example, 1 MHz, 2 MHz, 2.5 MHz, 4 MHz, 5 MHz, 7.5 MHz, 8 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz, 160 MHz, 80+80 MHz, and / or any bandwidth therebetween or any combination thereof can be used.

[0130] Receive power level threshold RX thres The determination may be based on an indicated transmit power, which may in particular be comprised in the transmitted frame or any control frame, management frame, extended frame, NDP frame, action frame or any other similar and / or appropriate frame.

[0131] According to one embodiment, a passive process for discovering and / or reporting STA neighbors may include monitoring the medium occasionally and / or periodically to scan neighboring STAs in a passive manner. The STA may monitor the medium to passively scan neighboring STAs when requested by another STA (e.g., an AP or any other STA) from the same or another BSS. The STA may report neighbors observed from its own BSS and / or neighbors observed from neighboring BSSs to any of the following: (1) its AP, (2) other STAs, (3) coordinating STAs, and / or (4) peer STAs, etc. The STA may use a typical neighbor report element or frame to report observed neighbors, in Fig.10 An example of this is shown in .

[0132] Fig.10 is a diagram showing a typical neighbor report frame.

[0133] After collecting information about STAs whose locations (e.g., geographic locations, communication locations, and / or working locations) are close to each other (e.g., by or with the aid of receiving a set of neighbor report elements and / or frames from one or more STAs (e.g., neighboring STAs), the STAs (e.g., APs) may assign some or all of the STAs whose locations are close to each other to one or more multi-user groups (e.g., MU OFDMA groups and / or high-efficiency (HE) MU OFDMA groups). In some examples, the STAs may assign STAs whose locations are close to each other (e.g., located nearby) and that can hear interference / packets from one or more OBSSs (e.g., specific OBSSs) to a multi-user group (e.g., MU OFDMA groups and / or HE MU OFDMA groups). In different examples, the AP may assign STAs that can hear interference / packets from one or more OBSSs (e.g., specific OBSSs) to a multi-user group (e.g., MU OFDMA groups and / or HE MU OFDMA groups).

[0134] A STA (e.g., an AP) may assign one or more resources (e.g., one or more specific channels, one or more subcarrier sets, and / or one or more resource blocks (RBs)) to a MU group (e.g., a MU OFDMA group and / or a HE MU OFDMA group), wherein the group includes or is composed of STAs that are located close to each other. A MU group may be used for and / or may be beneficial for a group of STAs that have a relatively fixed location over a period of time. A BSS and / or AP (e.g., each BSS and / or AP) may maintain a relatively interference-free set of resources (e.g., a subcarrier and / or RB set) in a coordinated manner with neighboring BSSs or APs. The resource set may be assigned to a STA that has high mobility (e.g., changes BSS and / or AP at a certain frequency threshold) and / or is transitioning and / or in transition mode.

[0135] If a STA (e.g., an AP) learns a STA (e.g., any STA) or a group of STAs from a specific OBSS (e.g., having a specific BSS color and / or BSSID) that can be heard by one or more STAs in its own BSS (e.g., STAs in a HE MU OFDMA group in the same BSS as the STA), the STA can provide such information to the AP or STA of the specific OBSS as part of the coordination process. For example, if a STA (e.g., an AP) learns a STA that is in the same BSS as the STA and hears one or more STAs of the OBSS, the STA can report information about the STA that hears the one or more STAs of the OBSS to the AP and / or STA of the OBSS. STAs (e.g., APs) in neighboring BSSs can perform coordination processes so that different resources (e.g., RBs, TXOPs, and / or time slots / access windows) are allocated to the STAs (e.g., STAs from different HE MU OFDMA groups belonging to different BSSs that may cause interference to each other), thereby reducing interference between BSSs.

[0136] After receiving one or more neighbor report frames, the STA (e.g., an AP or a STA performing coordination) may use the contents of the neighbor report frames to evaluate resource allocation in its BSS. After receiving a resource reallocation request in one or more neighbor report frames, the STA (e.g., an AP or a STA performing coordination) may evaluate resource allocation in its BSS, and / or may use the contents of the one or more neighbor report frames to implement resource reallocation. Additionally or alternatively, after receiving one or more neighbor report frames, the STA (e.g., an AP or a STA performing coordination) may use the contents of the one or more neighbor report frames to implement coordination processing with one or more OBSSs. After receiving a request for coordination / change (e.g., in one or more neighbor report frames), the STA (e.g., an AP or a STA performing coordination) may evaluate resource allocation in its BSS, may use the contents of the one or more neighbor report frames to implement coordination processing with one or more OBSSs, and / or may implement resource reallocation in its own BSS.

[0137] refer to Fig.10 , the neighbor report frame 1000 may include or comprise one or more of the following fields: a preamble 1001, a MAC header 1002, a frame body 1003, and / or a frame check sequence (FCS) 1004. One or more parts and / or fields of the neighbor report frame 1000 may include or comprise one or more of the following information: (1) a BSS identifier (BSSID) field 1005, which may be used to indicate the BSSID, compressed BSSID, BSS color and / or local BSSID of the STA performing the transmission, or any type of identifier similar to the BSSID and / or service set identifier (SSID); (2) a location field 1006 that may be used to indicate the location of the STA performing the report; (3) a same BSSID indicator 1006. 07, the same BSSID indicator 1007 can be used to indicate that the STAs contained or included in the neighbor report frame are from (for example, all from) the same BSS as the STA performing the transmission or the first neighbor indicated in the neighbor report frame; (4) the neighbor field number field 1008, the neighbor field number field 1008 can be used to indicate the number of neighbor fields contained or included in the neighbor report frame 1000; and / or (5) one or more neighbor fields 1009 from 1 to N, each of which can be used to indicate information about one or more STAs close to the STA performing the transmission or nearby it.

[0138] Each neighbor field may contain or include one or more of the following information: (1) a same BSSID indicator 1010, which may be used to indicate that the STA indicated in each neighbor field belongs to the same BSS as the STA performing the transmission or that the STA indicated in each neighbor field is in the same BSS as the STA indicated in the previous neighbor field. If the same BSSID indicator is turned on, the BSSID field may be skipped and / or not included; (2) a BSSID field 1011, which may be used to indicate the BSSID of one or more STAs indicated in the neighbor field 909 (e.g., a corresponding neighbor field, where if the neighbor report frame or the neighbor field contains or includes the same BSSID indicator that is turned on (e.g., at a first logical level), the BSSID field may be skipped or not included (the BSSID may be implemented as a BSSID, a compressed BSSID, a BSS color, a local BSSID, any type of BSSID identifier and / or SSID, etc.); and / or (3) a STA 1-STA N field 1012, which may be used to indicate the BSSID of one or more STAs indicated in the neighbor field 909 (e.g., a corresponding neighbor field, where if the neighbor report frame or the neighbor field contains or includes the same BSSID indicator that is turned on (e.g., at a first logical level), the BSSID field may be skipped or not included (the BSSID may be implemented as a BSSID, a compressed BSSID, a BSS color, a local BSSID, any type of BSSID identifier and / or SSID, etc.); and / or The N field 1012 may be used to respectively indicate information of observed neighboring STAs (eg, each, a portion, or all observed neighboring STAs).

[0139] Each STA field may contain or include one or more of the following information: (1) an ID field 1013 that may identify one or more neighboring STAs, such as a MAC address, AID, local AID, group ID, and / or any other type of ID that can be agreed upon by the STA and the AP; (2) a destination ID field 1014 that may identify a destination STA of one or more neighboring STAs (the destination ID may be implemented as a MAC address, AID, local AID, group ID, and / or any other type of ID that can be agreed upon by the STA and the AP (for example, if one or more neighboring STAs use different transmission powers when performing transmissions at different times or when performing transmissions for different destinations, then the destination ID may be used); (3) a receive power information field 1015 (such as an absolute level, a relative level, a range, and / or an average value, etc.) that may be used to indicate a receive power level (such as an absolute level, a relative level, a range, and / or an average value, etc.) used to receive the packet. (a) if the reporting STA knows the transmit power used by one or more neighboring STAs, the received power information may include the transmit power); (b) a resource usage field 1016 containing information that can be used to indicate the resources used by one or more observed neighboring STAs (e.g., access window, beacon interval, time slot, frequency bandwidth, one or more channels, one or more subcarrier sets, and / or one or more RBs, etc.); and (c) a location / distance field 1017 containing information that can be used to indicate the location and / or distance of the neighboring STA. The location / distance field 1017 may contain location information of the neighboring STA. In addition or alternatively, the location / distance field 1017 may contain a distance (e.g., an estimated distance) from the reporting STA to the neighboring STA. Such a distance may be determined based on the reported location and the location of the reporting STA, or may be estimated based on a received signal (e.g., a received power level).

[0140] Although in Fig.10Not shown, but the neighbor report frame may include or contain one or both of the following indicators: (1) resource reallocation request; and / or (2) coordination / change request. The resource reallocation request indicator may be used by the STA performing transmission to request that the STA performing reception (e.g., AP) should or will reallocate resources for it, and the reallocation may be based on the content of the neighbor report frame. The neighbor report frame may contain or include one or more coordination / change request indicators that may be used to indicate to the STA performing reception (e.g., AP or STA performing coordination) that it is about to implement coordination processing regarding resources / scheduling with one or more OBSSs. Such coordination / change regarding resource scheduling may be implemented using the content of the neighbor report frame. After receiving one or more neighbor report frames, the STA (e.g., AP or STA performing coordination) may use the content of the neighbor report frame to evaluate resource allocation in its BSS. After receiving the resource reallocation request (e.g., in one or more neighbor report frames), the STA (e.g., AP or STA performing coordination) may evaluate resource allocation in its BSS and / or may use the content of the neighbor report frame to implement resource reallocation. In addition or alternatively, after receiving one or more neighbor report frames, the STA (e.g., an AP or a STA performing coordination) may use the contents of the neighbor report frames to implement coordination processing with one or more OBSSs. After receiving a coordination / change request (e.g., in one or more neighbor report frames), the STA (e.g., an AP or a STA performing coordination) may evaluate resource allocation in its BSS and may use the contents of the neighbor report frames to implement coordination processing with one or more OBSSs and / or may implement resource reallocation in its own BSS.

[0141] According to one embodiment, any part of the neighbor report frame or any combination thereof may be implemented as a new control frame and / or a new management frame, such as an action frame, an action no-response frame and / or any other type of management frame, control frame, extended frame, NDP frame, NDP frame with MAC information, or any other similar and / or appropriate frame type, etc. The neighbor report frame may be implemented as an information element (IE), a sub-element, or a set and / or subset of fields or sub-fields of a management frame, a control frame, an extended frame, an NDP frame, and / or a data frame, and / or as part of a MAC / PLCP header. The neighbor report frame or any part thereof may be sent as part of an aggregated MAC protocol data unit (A-MPDU) or an aggregated MAC service data unit (A-MSDU).

[0142] Fig.11 is a diagram showing a typical discovery frame.

[0143] refer to Fig.11, a STA may use the discovery frame 1100 to advertise its presence to its neighbors so that its neighbors can determine the proximity of the transmitting STA. Fig.11 A discovery frame 1100 according to an exemplary embodiment is shown in FIG. The discovery frame 1100 may include or comprise one or more of the following fields: a preamble 1101 , a MAC header 1102 , a frame body 1103 , and / or a FCS 1104 . One or more parts of the discovery frame may contain or include one or more of the following information: (1) a BSSID field 1005, which may be used to indicate the BSSID, compressed BSSID, BSS color and / or local BSSID of the STA performing the transmission, or any type of identifier of the BSSID and / or SSID, etc.; (2) a location field 1106 that may indicate the location of the STA performing the transmission; (3) an ID field 1107 that may identify the STA performing the transmission (e.g., a MAC address, AID, local AID, group ID and / or any other type of ID that may be agreed upon by the STA and the AP); (4) a same BSSID field 1108 indicator that may indicate that the STA performing the transmission only requests responses from STAs of the same BSS; (5) a filter condition field 1109, which may be used to indicate that the STA performing the transmission only requests responses from STAs of the same BSS; (5) a TX power field 1110 that can be used to indicate the transmit power of the current frame; (6) a receive power threshold field 1111 that can be used to indicate a receive power threshold (as an example, a STA that receives a discovery frame with a receive power exceeding the indicated receive power threshold can respond to the discovery frame); and / or (7) a resource allocation field 1112 that can be used to indicate resources (e.g., time slots, beacon intervals, frequency channels, bandwidths, RBs and / or subcarrier sets, etc. allocated to the STA that performs the transmission).

[0144] According to one embodiment, any part of the discovery frame 1100 or any combination thereof can be implemented as a new control frame and / or a new management frame, such as an action frame, an action no-response frame and / or any other type of management frame, control frame, extended frame, NDP frame and / or NDP frame with MAC information. The discovery frame 1100 can be implemented as a set or subset of information elements, sub-elements, fields or sub-fields of a management frame, a control frame, an extended frame, an NDP frame and / or a data frame, and / or as part of a MAC / PLCP header. The discovery frame 1100 or any part thereof can be sent as part of an A-MPDU or an A-MSDU. It is conceivable that the discovery frame 1100 can be transmitted encrypted. In certain typical embodiments, as an example, the discovery frame 1100 can be transmitted without encryption to ensure that a predetermined neighboring STA can decode the frame.

[0145] According to one embodiment, a STA may use a proactive process to advertise its presence, and discover and report neighbors located near its geographic or communication and / or operating location according to any one or more of the following processes.

[0146] A STA can transmit a discovery frame to announce its presence to its neighbors. The transmission of discovery frames can be random, periodic, or based on a request from another STA (such as an AP). Fig.10 An example architecture / design for a discovery frame is shown in FIG. 1 . In some embodiments, a STA may transmit a Null Data Packet (NDP) frame as its discovery frame. A STA may request a response from a nearby neighboring STA by indicating a receive power threshold level in a discovery frame. A STA may request a response from a neighboring STA belonging to the same BSS by turning on the same BSSID indicator (e.g., setting the same BSSID indicator to “1”) in a discovery frame.

[0147] The STA may request responses from a set of neighbors by adding a filter condition corresponding to one or more of a BSSID, a BSS color, a SSID, a group ID, a MAC address, and / or an AID in a discovery frame. As an example, the filter condition may identify neighbors based on one or more BSSs, one or more SSIDs, one or more group IDs, a range of MAC addresses, and / or a range of AIDs, etc.

[0148] When receiving a discovery packet, a neighbor STA may extract one or more of the following information from the preamble, MAC header, and / or any part of the received discovery packet: (1) the MAC address of the STA performing the transmission and / or the STA performing the reception; (2) the BSSID; (3) the local AID (PAID); (4) the group ID; and / or (5) the packet reception power (e.g., RSSI, RCPI, and / or any other power metric).

[0149] The STA uses the information about all transmitting STAs or a subset thereof provided in the received discovery packet as the direct neighbors of the STA. For example, the receiving STA may record (e.g., only record) in the memory the STAs that are above or beyond a certain receive power level RX thres The STA performing the transmission (e.g., the identifier of the STA performing the transmission) provided in the received discovery packet, wherein the received power level can be indicated in the discovery frame. In some examples, the STA can record (e.g., only record) the STA performing the transmission (e.g., the STA identifier) ​​from the same BSS as itself. In a different example, the STA can record (e.g., only record) the STA performing the transmission from the same BSS as itself and whose packets have been received and are above and / or exceed the RX thres In some embodiments, the STA may record the received RX thres The STA performing the transmission of all packets (eg, STA identifier).

[0150] RX thres The determination may be based on an absolute received power measurement (e.g., if it is known that the transmitting STA uses a uniform transmit power). For example, if the transmitting STA can transmit with different channel bandwidths, and / or the RX power may be adjusted for the actual transmission frequency bandwidth. thres , then the power density can be used to indicate RX thres As an example, the different transmit frequency bandwidths may be 1 MHz, 2 MHz, 2.5 MHz, 4 MHz, 5 MHz, 7.5 MHz, 8 MHz, 10 MHz, 20 MHz, 40 MHz, 80 MHz, 160 MHz, 80+80 MHz, and / or any bandwidth therebetween or any combination thereof.

[0151] RX thresThe transmit power may be determined based on the indicated transmit power, which may be included in the transmitted discovery frame, and / or in any control frame, management frame, extended frame, NDP frame, action frame, and / or similar frame. The STA may monitor the medium sporadically or periodically to scan for neighboring STAs. The STA may monitor the medium to scan for neighboring STAs when requested by another STA (e.g., an AP) or another STA from the same or another BSS.

[0152] After receiving a discovery frame requesting a response frame, the STA may respond using a response discovery frame. For example, if the STA satisfies the filtering conditions (e.g., all filtering conditions) and / or criteria indicated in the discovery frame, the STA may respond using a response discovery frame. In some embodiments, the response discovery frame may be conditioned on the response criteria determined on the STA performing the reception. The transmission timing of the response discovery frame may be scheduled and / or set to have a random delay (as an example, thereby helping to prevent different STAs from responding at the same time). In some embodiments, after receiving one or more discovery frames requesting a response frame, if the STA satisfies the filtering conditions and criteria indicated in the discovery frame, the STA may respond by transmitting a neighbor report frame to another STA (e.g., its AP). In some embodiments, the response discovery frame may be conditioned on the response criteria determined on the STA performing the reception. The transmission timing of the neighbor report frame may be scheduled and / or set to have a random delay (as an example, thereby helping to prevent different STAs from responding at the same time).

[0153] A STA may report its observed neighbors in its own BSS and / or its observed neighbors from neighboring BSSs to its AP and / or one or more of the following: other STAs, STAs performing coordination, and / or peer STAs. A STA may report such information using a neighbor report element or a neighbor report frame, an example of which is in Fig. 9 Displayed in.

[0154] A STA (e.g., an AP) may collect information about STAs located close to each other from multiple STAs (e.g., by receiving a set of neighbor report elements, neighbor report frames, and / or discovery frames). After collecting such information, the STA may assign STAs that are determined to be close to each other and / or located close to each other to one or more multi-user groups (e.g., MU OFDMA groups and / or HE MU OFDMA groups). In some examples, a STA (e.g., an AP) may assign STAs that are located close to each other and can hear interference / packets from one or more OBSSs (e.g., specific OBSSs) to one or more multi-user groups (e.g., MU OFDMA groups and / or HE MU OFDMA groups). In a different example, an AP may assign STAs that are able to hear interference / packets from one or more OBSSs (e.g., specific OBSSs) to one or more multi-user groups (e.g., MU OFDMA groups and / or HE MU OFDMA groups).

[0155] A STA (e.g., an AP) may assign one or more resources (e.g., one or more specific channels, one or more subcarrier sets, and / or one or more resource blocks (RBs)) to one or more MU groups (e.g., MU OFDMA groups and / or HE MU OFDMA groups), wherein the groups may include or consist of STAs that are located close to each other. Such MU groups are very beneficial for groups of STAs that have relatively fixed positions over a period of time (e.g., a period exceeding a threshold). Each, some or all BSSs and / or APs may maintain a relatively interference-free set of resources, such as a certain subcarrier and / or RB set, by potentially coordinating with neighboring BSSs or APs. Such a set of resources may be assigned to STAs that have higher mobility (e.g., based on mobility parameters) and that are likely to be performing transmissions and / or may be in transmission mode.

[0156] If a STA (e.g., an AP) is aware of any STA or STA group from a particular OBSS that can be heard by one or more STAs in its own BSS (e.g., STAs of a HE MU OFDMA group in its own BSS), then the STA may provide such information to the AP or STA in the particular OBSS as part of the coordination process and / or operation. STAs (e.g., APs) in neighboring BSSs may perform coordination processes so that STAs (e.g., STAs from HE MU OFDMA groups that belong to different BSSs and may interfere with each other) may be allocated different resources (e.g., different RBs, different TXOPs, and / or different time slots / access windows), thereby reducing interference between BSSs. After receiving one or more neighbor report frames, a STA (e.g., an AP or a STA performing coordination) may use the contents of the neighbor report frames to evaluate resource allocations in its BSS.

[0157] After receiving a resource reallocation request (e.g., in one or more neighbor report frames), a STA (e.g., an AP or a STA performing coordination) may evaluate resource allocation in its BSS and may use the contents of the neighbor report frames to implement resource reallocation. Alternatively or additionally, after receiving one or more neighbor report frames, a STA (e.g., an AP or a STA performing coordination) may use the contents of the neighbor report frames to implement coordination processing with one or more OBSSs. After receiving a coordination / change request (e.g., in one or more neighbor report frames), a STA (e.g., an AP or a STA performing coordination) may evaluate resource allocation in its BSS, use the contents of the one or more neighbor report frames to implement coordination processing with one or more OBSSs, and may implement resource reallocation in its own BSS.

[0158] In certain typical embodiments, a process for configuring a STA to perform transmission and / or reception may be implemented by establishing a new or modified CCA process when a portion of a 20 MHz channel is busy. These CCA processes for 20 MHz channels may include the use of a PHY preamble. The PHY preamble may be enhanced to facilitate more flexible frequency reuse in 20 MHz CCA (e.g., by responding to BW / tone assignments from the AP in the PHY preamble). This process of responding to BW / tone assignments may facilitate STAs in neighboring BSSs to correctly and / or quickly determine which frequency resources are not occupied. For example, in Figure 8 In the UL-OFMDA scenario, the BSS-B STA and the BSS-C STA that are in the UL-OFMDA scenario and cannot hear the BSS-A AP can benefit from the information carried by the 10 MHz UL PPDU preamble from the BSS-A STA2 and / or the BSS-A STA1.

[0159] According to one embodiment, for DL ​​transmission in OBSS, as described below with reference to Figure 8 As described, the OBSSSTA can reply to the bandwidth signaling RTS transmitted by the OBSS AP on multiple 20MHz channels. If a CTS frame and / or an NDP frame are used on multiple 20MHz channels to reply to a non-high throughput (HT) repeated RTS for initiating DL transmission from a BSS-B / C AP, the CTS frame and / or the NDP frame may include one or more of the following information: (1) available frequency resources below 20MHz in 20MHz channels not used by BSS-B; (2) timing adjustment regarding DL data frames; (3) PPDU length restrictions, such as upper and / or lower limits; (4) RSSI of channels below 20MHz used by the OBSS; and / or 4) signal configuration parameters of channels below 20MHz used by the OBSS, etc.

[0160] As an example, if Figure 8In the UL-OFDMA scenario, if the BSS-B STA and / or BSS-C STA can receive the bandwidth signaling RTS frame and / or NDP frame in a channel adjacent to / different from the channel on which the BSS-B operates, then for the 20 MHz channel used by the BSS-B, the BSS-B STA and / or BSS-C STA can reply with a CTS frame and / or NDP frame containing or including one or more of the following information: (1) an indication to its corresponding BSS-B / C AP regarding which resource data frames can be received without interference; (2) an indication to the BSS-C / B AP regarding adjustments associated with OFDM symbol boundaries in the RTS frame, wherein the adjustments cause the received DL data frame to be aligned with the OFDM symbols sent by BSS-A STA1 and / or STA2, thereby minimizing the inter-symbol interference of the UL frame from the BSS-A STA; (3) an indication to the BSS-B and / or BSS-C AP regarding which resource data frames can be received without interference; (4) an indication to the BSS-C / B AP regarding adjustments associated with the OFDM symbol boundaries in the RTS frame; and (5) an indication to the BSS-B and / or BSS-C AP regarding adjustments associated with the OFDM symbol boundaries in the RTS frame. (4) an indication of the AP regarding a DL data length limit, wherein the limit causes the BSS-B and / or BSS-C STA not to transmit an ACK regarding a DL frame at the same time that the BSS-A STA1 and / or BSS-A STA2 can receive its ACK; (5) an indication of the BSS-B and / or BSS-C AP regarding the signal strength (e.g., by means of RSSI) that may be introduced by adjacent channel interference (ACI) of an occupied subchannel. The BSS-B and / or BSS-C AP may choose to change the transmit power of the MCS level in order to perform reliable signal reception on its STAs; and (6) an indication of other signal configuration parameters (e.g., FFT size and / or GI length, etc.) for the BSS-B and / or BSS-C AP (for example, thereby avoiding ACI caused by inconsistencies in system parameters used between adjacent channels and / or subchannels).

[0161] Typical process for CSMA / CA using OFDMA

[0162] In some representative embodiments, a STA process for contending for the medium may be implemented. As an example, different STAs may contend for subchannels (e.g., each subchannel, a portion of subchannels, and / or all subchannels) at the beginning of a frame. In some exemplary embodiments, a resource contention method for subchannelized transmission may be implemented using a mobile slotted Aloha process. In some exemplary embodiments, as an example, the above process may be modified to counter interference from hidden nodes.

[0163] Fig.12 is a diagram illustrating sub-channelized carrier sense multiple access (CSMA) operation.

[0164] refer to Fig.12, the sub-channelized CSMA operation can be performed according to the following process. A STA (e.g., each STA, a part of the STAs, or all STAs) can have a preferred transmission sub-channel. In some embodiments, a STA can use a common sub-channel as its preferred transmission sub-channel. A STA can have any number of prioritized preferred sub-channels (e.g., the second, third, and Mth preferred sub-channels). As an example, each STA can have M ordered preferred sub-channels labeled from 1, 2, ..., M. When the AP knows or determines that multiple STAs are going to send data in the UL, the AP can send a trigger frame 1201 for UL-OFDMA transmission, where this trigger frame can be referred to as the AP trigger 1201 or the AP trigger frame 1201. The trigger frame 1201 can contain or include a legacy preamble for reserving a transmission opportunity (TXOP) for the length of the subsequent uplink OFDMA frame. After the trigger frame 1201 and the SIFS duration 1209, N STF periods (this period can also be referred to as the HE-SUB-STF period 1210) will be reserved for STF transmission. The maximum number of the N STF periods can be 10, 15, 20, and / or any other similar and / or appropriate number of STF periods. These STFs can have periods of 0.8, 1.6, 3.2, and / or any other similar and / or appropriate amount of microseconds.

[0165] During the process of competing for the transmission opportunity in any sub-channel, each STA can generate a random integer y from a uniform distribution U[0,N]. If y < x, and where x depends on the traffic access category, sub-channel ID, and / or the maximum period N, then the STA can back off for y periods. Each STA can compete (e.g., contend) for and / or acquire a sub-channel in the same transmission band. The back-off unit for each STA is the period of the HE-SUB-STF. For x that depends on the traffic access category, an example of the x can be xsub_id = min(N, AC-Psub_id).

[0166] If the data has a higher access category (AC), then the value of x will be higher, and if the STA has priority in one of the subchannels (e.g., a lower priority number Psub_id), then the value of x for the subchannel will be higher. The value of x may have an upper limit based on N. For example, the value of x may be an upper limit bounded by N, where N is the maximum number of STF cycles. The number xsub_id may determine the priority of the STA in the subchannel indicated by sub_id. Any other appropriate and / or similar linear or nonlinear function of N, AC, Psub_id may be used to calculate the value of x. In addition, without loss of generality, reverse logic may be applied, where a lower value of x may represent a higher priority. For this logic, the random integer generated by the STA must be greater than the priority xsub_id. Before transmission, the STA may perform CCA on the subchannel indicated by sub_id. The method and threshold for such CCA may be similar to the method described above.

[0167] If the subchannel is determined to be idle, the STA may send Ny HE-SUB-STFs corresponding to the remaining amount of time allocated. The STF transmissions from all STAs may be completed simultaneously, where the time is when they (e.g., each STA) may send a subchannelized LTF (which may be part of a physical layer convergence protocol (PLCP) header) to assist in subchannel estimation on the AP. If a conflict occurs, the value of Psub_id or x may be changed (e.g., reduced or increased). A conflict may indicate the presence of a hidden node, whereby the priority of the STA in the subchannel may be reduced.

[0168] If the subchannel is not idle, the STA may attempt to sense another prioritized and / or preferred channel assigned by the AP (a second preferred channel or a third preferred channel, etc.). If no transmission exists on a particular channel sensed, the STA may send one or more remaining STFs on that channel and may continue to perform data transmission. In some embodiments, the STA may postpone transmission until the next available uplink trigger.

[0169] refer to Fig.12, as an example, AP 602 may transmit an AP trigger 1201. After the AP trigger frame 1201, STAs 1 to 5 may contend for and / or acquire a subchannel after a SIFS duration 1209. In operation 1202, STA 1 may obtain a medium located at the fifth HE-SUB-STF, such as a first subchannel. In operation 1203, STA 2 may obtain another medium located at the second HE-SUB-STF, such as a second subchannel. In operation 1204, STA 3 may sense a second subchannel located at the sixth HE-SUB-STF and may determine that the subchannel is busy. In operation 1205, STA 4 may obtain a medium located at the first HE-SUB-STF, such as a third subchannel. In operation 1206, STA 5 may attempt to obtain a medium located at the fifth HE-SUB_STF, such as a third subchannel, but may determine that the third subchannel is busy. In operation 1207, STA 5 may obtain a medium located at the sixth HE-SUB-STF, such as a fourth subchannel. In operation 1208, STA 3 may sense the fourth subchannel located at the seventh HE-SUB-STF and may determine that the subchannel is busy. STAs 1 to 5 that have respectively acquired the medium may respectively transmit HE-SUB-LTF 1211 and HE-SIG and HE-data 1212 after respectively transmitting HE-SUB-STF 1210.

[0170] In certain exemplary embodiments described herein, the overhead for scheduling can be reduced while still maintaining fairness to all STAs. If there are hidden nodes, and if the hidden nodes perform transmissions on the same subchannel at the same time, there may be contention. To minimize any contention, the AP can avoid assigning the same preferred subchannel to STAs that are sensed by the AP to be in two physically opposite sectors.

[0171] The data length duration may be assigned and / or may be announced by the AP in a trigger frame. It is conceivable that if a STA wakes up from sleep, then the STA may scan the entire band to check if there is an ongoing transmission on any band. The STA may assume that there is an ongoing transmission from a hidden node and may avoid transmitting on any subchannel until the next trigger frame.

[0172] Fig.13 is a diagram showing a typical sub-channelized CSMA operation with dual triggering.

[0173] refer to Fig.13 As an example, to avoid hidden nodes, sub-channelized CSMA operation can be performed in the following manner and by using double triggering:

[0174] The trigger frame 1301 (which may be referred to as the first AP trigger frame 1301 or the first AP trigger 1301) may be sent by the AP 602 and may be considered as trigger information for starting a CSMA backoff process in a subchannel (e.g., each subchannel). Once a STA (e.g., STA 1, STA 2, STA 3, STA 4, or STA5 or each of STAs 1-5) finishes competing for a subchannel and acquires a subchannel, the STA (e.g., STA 1) may send a SIG field with its information to the AP 602. The information may include its own local AID (PAID), and by using the PAID information, the AP 602 will know and / or may determine which STAs (e.g., STA 1, STA 2, STA 3, STA 4, and / or STA5) have acquired the medium. If there is a conflict in the subchannel due to a hidden node, the AP 602 will not be able to decode the SIG in the subchannel and may be aware of the conflict. In this case, the AP 602 will not allocate the subchannel to any STA (e.g., STA 1). If no node (e.g., STA) contends for any particular subchannel, the AP 602 does not allocate the subchannel. According to some embodiments, the AP 602 may allocate the subchannel to a safe STA (e.g., STA 1), which may be a STA that is known and / or determined by the AP 602 to be not affected by hidden nodes, for example.

[0175] The AP 602 may announce the IDs of one or more STAs (e.g., STA 1, STA 2, STA 3, STA 4, or STA 5) that have acquired the TXOP and the subchannels allocated thereto in a second trigger frame 1313 (which may be referred to as a second AP trigger frame 1313 or a second AP trigger 1313). The process of using the second trigger frame 1313 to announce one or more IDs may generally be referred to as a group clear to send (G-CTS) frame. The TXOP may be for a DL-OFDMA frame. This frame may have a PLCP header (e.g., only a PLCP header) and may include a sub-channelization or regular SIG field. All STAs can read the channelized SIG field (e.g., a combined SIG field containing common and / or individual information of each / all STAs (e.g., STA 1, STA 2, STA 3, STA 4, or STA 5) transmitted on all sub-channels) or the sub-channelized SIG field (e.g., a sub-channelized SIG field transmitted for each STA (e.g., STA 1, STA 2, STA 3, STA 4, or STA 5) within its sub-channel) so that the corresponding STA can determine whether it obtains the TXOP. These STAs (e.g., STA 1, STA 2, STA 3, STA 4, or STA 5) can obtain the data to be transmitted in the TXOP until the end of the TXOP. If the buffer is empty, then these STAs (e.g., STA 1, STA 2, STA 3, STA 4, or STA 5) can fill the data with zero values.

[0176] refer to Fig.13, as an example, AP 602 may transmit an AP trigger frame 1301. After a SIFS duration 1309 has passed after the AP trigger frame 1301, STA 1-5 may contend for and / or acquire a subchannel. In operation 1302, STA 1 may acquire a medium located at the fifth HE-SUB-STF, such as a first subchannel, from HE-SUB-STF 1310. In operation 1303, STA 2 may acquire another medium located at the second HE-SUB-STF, such as a second subchannel. In operation 1304, STA 3 may sense a second subchannel located at the sixth HE-SUB-STF and may determine that the subchannel is busy. In operation 1305, STA 4 may acquire a medium located at the first HE-SUB-STF, such as a third subchannel. In operation 1306, STA 5 may attempt to acquire a medium located at the fifth HE-SUB_STF, such as a third subchannel, but may determine that the third subchannel is busy. At operation 1307, the STA may acquire the medium located at the sixth HE-SUB-STF, for example, the fourth subchannel. At operation 1308, STA 3 may sense the fourth subchannel located at the seventh HE-SUB-STF and may determine that the subchannel is busy. STAs 1-5 may receive a second AP trigger 1313, wherein the trigger indicates the IDs of STAs 1-5 that have respectively acquired the medium and the subchannels allocated thereto. STAs 1-5 (for example, Fig.13 As shown, STA 1, STA 2, STA 4 or STA 5) can transmit HE-SUB-LTF and HE-SIG 1311 and HE-SIG and HE-data 1312 respectively.

[0177] Fig.14 is a diagram showing a typical slotted sub-channelized CSMA operation.

[0178] The frame can be extended (for example, approximately 4 times compared to the previous WLAN PHY standard), which can increase the duration of each PPDU. For time-varying channels, the channel can change during the transmission of the PPDU. As an example, by implementing a midamble, channel estimation errors caused by time-varying channels can be corrected. The midamble can use a portion of the PLCP header and can be repeated one or more times in the middle of the frame. The midamble can be sub-channelized. As a derivative, the midamble can create time slots in an existing transmission. If the transmission on the subchannel (for example, part of an existing transmission) ends, then these time slots can allow other STAs to contend for the subchannel during the existing transmission.

[0179] Unlike the MS-Aloha mentioned above, the WLAN frame does not have "Coordinated Universal Time". The HE-SUB-STF in the midamble can serve as an anchor point for other STAs to join the ongoing transmission on an idle subchannel. A STA that wants to transmit data in the uplink but does not have a TXOP can constantly sense the lack of power of the ongoing subchannelized transmission. If the subchannel is found to be empty, the WTRU will wait for the HE-SUB-STF of the midamble on other subchannels to start contention and / or competition for the subchannel. Each STA can have its preferred transmission subchannel, and multiple STAs can have the same subchannel (e.g., a common subchannel) as their preferred transmission subchannel. Each STA can have a second and / or third preferred subchannel. In one example, each STA can have M ordered and preferred subchannels labeled from 1, 2, ..., M. When the AP knows and / or determines that multiple STAs are to send data in the uplink, the AP can send a trigger frame for uplink OFDMA. The trigger frame may include scheduling information about which STAs will perform transmissions on which subchannels.

[0180] In some typical embodiments, the trigger frame may indicate (e.g., may only indicate or just indicate) the start of the contention period, and the STA may contend for the subchannel in the manner described above. The trigger frame may contain or include an old preamble that retains the TXOP related to the subsequent subchannelized frame length. Each STA may transmit a subchannelized PLCP header containing a subchannelized SIG and a predetermined number of data OFDMA symbols (e.g., d_segment). The number of data OFDMA symbols (d) may be negotiated within each BSS or extended service set (ESS). In some embodiments, d may be preset. It is conceivable that a midamble may be inserted after d_segment data OFDMA symbols. If the STA has to send data after d_segment OFDMA symbols, they can reacquire the subchannel by sending a midamble, and can continue to send data through the same subchannel. If the STA has no more data to send after sending d_segment OFDMA symbols, it can avoid sending a midamble. Doing so means releasing the subchannel.

[0181] For a STA that cannot perform a transmission in this segment of the frame, it can monitor the subchannel availability on each intermediate code. Since there will be multiple STAs waiting for the subchannel to be available, these STAs may compete for it. If one of the subchannels is released (e.g., just released) and the STA wants to send data, then as described here, the STA can generate a random integer y from the uniform distribution U[0,N]. If y < x (where x depends on the access category, subchannel ID, and / or the maximum period (N)), then the said station will back off for y periods. Before transmission, the STA can perform CCA again on this subcarrier. If the subchannel is or is found to be idle, then the STA can send N - y STFs, where the STFs can be calibrated with the intermediate codes of the HE-SUB-STFs from other STAs that may have regained the medium for continuous transmission. The STA and other STAs can send the intermediate code LTF (e.g., the subchannelized LTF, which can be part of the intermediate code PLCP) to re-estimate the channel. If the subchannel is not or was not idle, then the STA can sense another preferred channel assigned to it (e.g., the second preferred channel related to the priority ranking of the preferred channels). If there is no ongoing transmission on the preferred channel, then the STA can send the remaining STFs and data on this preferred channel.

[0182] The STA can continue to use the subchannel until the main TXOP of the said AP is completed (e.g., ends). This channel assignment scheme can enable continuous data transmission and can enable reduced overhead long frames similar to MS-Aloha. This channel assignment scheme can maintain CSMA-like fairness for STAs (e.g., all STAs). If there are hidden nodes and if the hidden node performs a transmission on the same subchannel simultaneously, then there may be contention. To minimize this contention, the AP can avoid assigning the same preferred subchannel to different STAs that are sensed and / or determined by the AP to be in two physically opposite sectors (directions) relative to itself. In this exemplary embodiment, the number of OFDMA symbols (d_segment) between each intermediate code and / or preamble and the intermediate code can be known, pre-assigned, or announced by the AP in the trigger frame. It should be contemplated that if the STA wakes up from sleep, then the STA can scan the entire frequency band, and if there is an ongoing transmission in any frequency band, then the STA can determine that the existing transmission is from a hidden node and can avoid transmitting on any subchannel until the next trigger frame.

[0183] Reference Fig.14, as an example, AP 602 may send an AP trigger frame 1401. After a SIFS duration 1413 has passed after the AP trigger frame 1401, STAs 1-6 may contend for and / or acquire a subchannel. In operation 1402, STA 1 may acquire a first subchannel located at a fifth HE-SUB-STF from the HE-SUB-STF 1415 of the first time slot 1419, and may release the first subchannel after the end of the first time slot 1419. In operation 1403, STA2 may acquire a second subchannel located at a second HE-SUB-STF in the first time slot 1419, and may transmit a midamble 1418 (e.g., by transmitting the HE-SUB-STF 1415 in the second time slot 1420), and continue to send the HE-SUB-LTF and the HE-SIG 1416 and the HE-data 1417 in the second time slot 1420. In operation 1404, STA 5 may sense the second subchannel of the sixth HE-SUB-STF located in the first time slot 1419, and may determine that the subchannel is busy. In operation 1408, STA 5 may sense the fourth subchannel of the seventh HE-SUB-STF located in the first time slot 1419, and may determine that the subchannel is busy.

[0184] In operation 1405, STA 3 may acquire a third subchannel located on the first HE-SUB-STF of the first slot 1419, and may release the third subchannel after the first slot 1419 ends. In operation 1406, STA 4 may attempt to acquire a third subchannel located on the fifth HE-SUB_STF of the first slot 1419, and may determine that the third subchannel is busy. In operation 1407, STA 4 may acquire a fourth subchannel located on the sixth HE-SUB-STF of the first slot 1419, and may send data in the first slot 1419 and the second slot 1420. In operation 1409, STA 5 may acquire a first subchannel in the first HE-SUB-STF of the second slot 1420. In operation 1410, STA 6 may attempt to obtain a first subchannel in a second HE-SUB-STF located in a second slot 1420, and in operation 1411, STA 6 may attempt to obtain a second subchannel located on a third HE-SUB-STF located in the second slot 1420, and may determine that the first and second subchannels are busy, respectively. In operation 1412, STA 6 may obtain a third subchannel located on a fourth HE-SUB-STF located in the second slot 1420.

[0185] Fig.15 is a diagram showing a typical slotted sub-channelized CSMA operation with dual triggering.

[0186] For slotted sub-channelized CSMA operation, after a midamble (e.g., each midamble), the AP 602 may send a trigger frame, such as a second trigger frame 1509 (which may also be referred to as a second AP trigger frame 1509) or a third trigger frame 1518 (which may also be referred to as a third AP trigger frame 1518), thereby updating the TXOP. As an example, the first trigger frame 1501 (which may also be referred to as a first AP trigger frame 1501) may be a trigger for initiating a CSMA backoff process or procedure in a subchannel (e.g., each subchannel). The first trigger frame 1501 may have an initial schedule, wherein the initial schedule includes information indicating the STAs 1-6 that are to perform transmissions and the subchannels for the STAs 1-6 to perform transmissions. The STAs 1-6 may perform a backoff process or procedure after the first trigger frame 1501. After the STAs 1-6 (e.g., one or more specific STAs or each STA) have finished competing for the subchannels and acquired the one or more subchannels, the STAs 1-6 may send a corresponding SIG field with their information. This information may include its own PAID.

[0187] By using the PAID information of the STAs 1-6 (e.g., each STA) that have obtained the subchannel, the AP 602 can learn or determine which STA 1-6 has obtained the medium. If there is or has been any conflict in any subchannel due to a hidden node, the AP 602 will not be able to decode the SIG field in the subchannel, and based on the fact that the AP 602 does not decode the SIG field, the AP 602 can learn or determine the existence of the hidden node and information related to the conflict itself. If there is no contention for any particular subchannel, the AP 602 will not allocate the particular subchannel to any STA 1-6. In some embodiments, the AP 602 can allocate the subchannel to a safe STA (e.g., a STA that has been known and / or determined by the AP 602 to not be affected by the hidden node). The AP 602 can announce the IDs of one or more STAs 1-6 that have obtained the TXOP and the corresponding subchannels allocated to them in the second trigger frame. The STAs 1-6 that have obtained the TXOP can then start to perform transmission until the end of the first time slot.

[0188] If a STA (e.g., STA 1) wants to continue transmitting after the midamble, then the STA (e.g., STA 1) can have priority on the subchannel until the initial TXOP for the AP 602 ends. After transmitting d_segment OFDMA symbols in one or more of its OFDMA symbols, STA 1 can continue to send the midamble. STAs 1-6 that cannot perform transmission in this segment of the frame (e.g., after the midamble) can monitor the subchannel availability on the midamble (e.g., each midamble). Since multiple STAs 1-6 will wait for the subchannel to be available, each STA 1-6 will compete for an open subchannel. After successfully competing for an open subchannel and being able to send a complete midamble, STA 1 can send a subchannelized SIG message including its PAID.

[0189] By using the SIG information, the AP 602 can know or determine which STAs 1-6 have obtained the medium. If there is a conflict in any subchannel due to a hidden node, the AP 602 will not be able to decode the SIG field in the subchannel, and the AP 602 will be aware of the conflict (as an example, it may be attributed to the hidden node). The AP 602 will not allocate the subchannel (e.g., the subchannel in which the SIG field is not successfully decoded) to any STA 1-6. If STA 1-6 does not compete for one or more specific subchannels, the AP 602 will not allocate the one or more specific subchannels. The AP 602 may announce the ID of one or more STAs 602 that have obtained the TXOP and the one or more corresponding subchannels allocated thereto in the second trigger frame. The second trigger may be considered as a group clear to send (G-CTS) frame and may be a DL-OFDMA frame. The second trigger frame may have (e.g., may only have) a PLCP header including a subchannelized SIG field or a regular SIG field. All STAs 602 are able to read the SIG field of the second trigger and may know whether they have obtained the TXOP. STAs 1-6 that have obtained the TXOP may continue to perform transmission until d_segment OFDMA symbols are transmitted.

[0190] After transmitting d_segment OFDMA symbols, if STA 1-6 determines that it still wants to continue transmission, it can continue transmission by sending a midamble and can reacquire the subchannel. After transmitting d_segment OFDMA symbols, if any STA 1-6 has no data to send in the uplink, then the STA can avoid sending a midamble. Avoiding sending a midamble can imply releasing the subchannel. This process of continuing to reacquire the subchannel by STA 1-6 and sending a trigger frame by AP 602 after each midamble can continue until the initial TXOP acquired by AP 602 is completed (e.g., ended). After the midamble for STA 1-6 (e.g., all STAs) that have ended transmission, AP 602 can piggyback an ACK or BA along with the trigger frame.

[0191] In some embodiments, the second trigger may include one or more fields for use by the manufacturer (eg, for manufacturer-related information) and / or one or more reserved fields, and the like.

[0192] refer to Fig.15 , as an example, AP 602 may transmit an AP trigger frame 1501. After a SIFS duration 1526 has passed after the AP trigger frame 1501, STA 1-STA 6 may contend for and / or acquire a subchannel. In operation 1502, STA 1 may obtain a medium, e.g., a first subchannel, on the fifth HE-SUB-STF located in the first time slot 1527, and may release the first subchannel after the end of the first time slot 1527. In operation 1503, STA 2 may obtain a second subchannel on the second HE-SUB-STF located in the first time slot 1527, and may transmit a midamble 1529 (e.g., by transmitting in the HE-SUB-STF 1523 in the second time slot 1528), and may continue to transmit the HE-SUB-LTF and HE-SIG 1524 and HE-data 1525 in the second time slot 1528. In operation 1504, STA 5 may sense the second subchannel on the sixth HE-SUB-STF located in the first time slot 1527, and may determine that the subchannel is busy. In operation 1508, STA 5 may sense the fourth subchannel on the seventh HE-SUB-STF located in the first time slot 1527, and may determine that the subchannel is busy.

[0193] In operation 1505, STA3 may obtain the third subchannel of the first HE-SUB-STF located in the first time slot 1527, and may release the third subchannel after the first time slot 1527 ends. In operation 1506, STA 4 may attempt to obtain the third subchannel of the fifth HE-SUB_STF located in the first time slot 1527, and may determine that the third subchannel is busy. In operation 1507, STA 4 may obtain the fourth subchannel of the sixth HE-SUB-STF located in the first time slot 1527, and may transmit data in the first time slot 1527 and the second time slot 1528. In operation 1510, STA 1 may transmit HE-data 1525 after receiving the second AP trigger frame 1509. Similarly, in operations 1511, 1512, and 1513, STA2, STA3, and STA4 may transmit HE-data 1525, respectively, after receiving the second AP trigger frame 1509. In operation 1514, STA 5 may obtain a first subchannel in a first HE-SUB-STF located in a second slot 1528. In operation 1515, STA 6 may attempt to obtain a first subchannel in a second HE-SUB-STF located in the second slot 1528, and in operation 1516, STA 6 may attempt to obtain a second subchannel of a third HE-SUB-STF located in the second slot 1528, and may determine that the first and second subchannels are busy, respectively. In operation 1517, STA 6 may obtain a third subchannel of a fourth HE-SUB-STF located in the second slot 1528. In operation 1519, STA 5 may transmit HE-data 1525 after receiving the third AP trigger frame 1518. Similarly, in operations 1520, 1521, and 1522, STA 2, STA 6, and STA 4 may transmit HE-data 1525, respectively, after receiving the third AP trigger frame 1518.

[0194] Fig.16 is a flow chart illustrating a typical method of performing sub-channelized CSMA operation by a STA.

[0195] like Fig.16As shown, according to one embodiment, STA 601 may perform subchannelized CSMA operation 1600 as described below. In operation 1601, STA 601 may send control information including a subchannel SIG field indicating the identity of STA 601 via an uplink. The control information may include a SIG field indicating that STA 601 is capable of receiving subfield allocations and / or is capable of performing operations in accordance with subchannel allocations. The control information may include a preamble 1001. In operation 1603, STA 601 may receive a trigger frame 1201 indicating one or more subchannels that can be obtained from a plurality of subchannels, wherein the one or more subchannels may be indicated based on a subchannel set. In operation 1605, STA 601 may determine which of the one or more subchannels are to be acquired. In operation 1505, STA 601 may use the acquired one or more acquired subchannels and send data via an uplink.

[0196] Fig.17 is a flow chart illustrating an exemplary method by the AP 602 to perform sub-channelized CSMA operation using dual triggering.

[0197] like Fig.17 As shown, according to one embodiment, AP 602 may perform sub-channelized CSMA operation 1700 as described below. At operation 1701, AP 602 may receive control information including a sub-channel SIG field indicating an identity of station (STA) 601 via an uplink. The control information may include a SIG field indicating that STA 601 is capable of receiving sub-channel allocation and / or is capable of performing operations in accordance with sub-channel allocation, and may include a preamble 1001. At operation 1703, AP 602 may transmit a trigger frame indicating one or more sub-channels that can be obtained from a plurality of sub-channels to STA 601, wherein the one or more sub-channels may be indicated based on a sub-channel set. At operation 1705, AP 602 may use the acquired one or more sub-channels and receive data via an uplink.

[0198] Although the features and elements are described above in specific combinations, one of ordinary skill in the art will recognize that each feature or element may be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware that is incorporated into a computer-readable medium for execution by a computer or processor. Examples of non-transitory computer-readable media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, buffer memory, semiconductor storage 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 associated with the software may be used to implement a radio frequency transceiver for use in a WTRU 102, UE, terminal, base station, RNC, or any computer host.

[0199] In addition, processing platforms, computing systems, controllers and other devices including processors are mentioned in the above embodiments. These devices may include at least one central processing unit ("CPU") and memory. According to the practice of technicians in the field of computer programming, references to the behavior or symbolic representation of operations or instructions may be performed by different CPUs and memories. Such behaviors and operations or instructions may be referred to as "running", "computer running" or "CPU running".

[0200] Those of ordinary skill in the art will appreciate that the behavior and symbolically represented operations or instructions include the manipulation of electronic signals by the CPU. The electronic system represents data bits that may cause the electronic signals to be transformed or reduced thereby, and the data bits are stored in memory locations in the memory system, thereby reconfiguring or otherwise changing the CPU operation and other signal processing. The memory location that holds the data bit is a physical location with specific electrical, magnetic, optical or organic properties that correspond to or represent the data bit. It should be understood that the exemplary embodiments herein are not limited to the above-mentioned platforms or CPUs, and other platforms and CPUs can also support the provided methods.

[0201] The data bits may also be stored on a computer-readable medium, including a magnetic disk, an optical disk, or any other volatile (e.g., random access memory ("RAM")) or non-volatile (e.g., read-only memory ("ROM")) mass storage system readable by the CPU. The computer-readable medium may include cooperating or interconnected computer-readable media, which may exist alone on a processing system or distributed among multiple interconnected processing systems located locally or remotely from the processing system. It should be understood that these exemplary embodiments are not limited to the above-mentioned memories, and other platforms and memories may also support the described methods.

[0202] In an illustrative embodiment, any operations, processes, etc. described herein may be implemented as computer-readable instructions stored on a computer-readable medium. The computer-readable instructions may be executed by a processor of a mobile unit, a network component, and / or any other computing device.

[0203] There is little distinction between hardware and software implementations of various aspects of the system. Whether to use hardware or software is often (but not always, as the choice between hardware and software may be important in certain contexts) a design choice that represents a compromise between cost and efficiency. The processes and / or systems and / or other techniques described herein may be implemented by a variety of carriers (e.g., hardware, software, and / or firmware), and the preferred carrier may change with the context in which the processes and / or systems and / or other techniques are deployed. For example, if the implementation determines that speed and accuracy are primary, then the implementer may choose to primarily use hardware and / or firmware carriers. Alternatively, the implementer may choose some combination of hardware, software, and / or firmware.

[0204] The above detailed description has been described with the aid of block diagrams, flow charts and / or examples to describe different embodiments of the device and / or process. Just as such block diagrams, flow charts and / or examples contain one or more functions and / or operations, those skilled in the art will understand that each function and / or operation within such block diagrams, flow charts or examples can be implemented individually and / or collectively by a wide range of hardware, software, firmware or nearly any combination thereof. As an example, suitable processors include general-purpose processors, special-purpose processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with a DSP core, controllers, microcontrollers, application-specific integrated circuits (ASICs), application-specific standard products (ASSPs); field-programmable gate array (FPGA) circuits, any other type of integrated circuit (IC), and / or state machines.

[0205] Although features and elements are provided in a specific combination in the above, it will be understood by those skilled in the art that each feature or element can be used alone or in combination with other features and elements. The present disclosure is not limited according to the embodiments described in the present application, wherein the purpose of the embodiments is to illustrate different aspects. It will be understood by those skilled in the art that numerous modifications and changes are possible without departing from the essence and scope. Unless provided in an explicit manner, the elements, behaviors or instructions used in the specification of the present application should not be interpreted as being essential to the present invention. In addition to the methods and devices enumerated here, those skilled in the art can clearly understand from the above description that the functionally equivalent methods and devices within the scope of the present disclosure. Such modifications and changes should all fall within the scope of the appended claims. The present disclosure is limited only in accordance with the appended claims and the full range of equivalents that such claims have. It should be understood that the present disclosure is not limited to a specific method or system.

[0206] It should also be understood that the terms used herein are used only to describe specific embodiments and are not intended to be limiting. When referred to herein, the terms "station" and their abbreviations "STA", "user equipment" and their abbreviations "UE" used herein may refer to (i) a wireless transmit and / or receive unit (WTRU) as described below; (ii) any one of the multiple embodiments of the WTRU described below; (iii) a device with wireless capabilities and / or wired capabilities (e.g., connectable), in particular, the device is configured with some or all of the structures and functions of the WTRU described above; (iii) a device with wireless capabilities and / or wired capabilities configured with relatively fewer structures and functions than all of the structures and functions of the WTRU described above; or (iv) a similar device. Details regarding an exemplary WTRU that may represent any UE described herein are referenced below. Figure 1-5 Provided.

[0207] In certain typical embodiments, several portions of the subject matter described herein may be implemented with the aid of an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal processor (DSP), and / or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein may be implemented in whole or in part in an integrated circuit in an equivalent manner, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as nearly any combination thereof, and that circuit design and / or code writing for software and / or firmware are also within the technical scope of those skilled in the art in accordance with the present disclosure. In addition, those skilled in the art will appreciate that the mechanisms of the subject matter described herein may be distributed in various forms as a program product, and that the illustrative embodiments of the subject matter described herein are applicable regardless of the particular type of signal-bearing medium used to actually perform the distribution. Examples of signal bearing media include, but are not limited to, the following: recordable media, such as floppy disks, hard drives, CDs, DVDs, digital tapes, computer memory, etc., and transmission type media, such as digital and / or analog communication media (e.g., optical cables, waveguides, wired communication links, wireless communication links, etc.).

[0208] The subject matter described here sometimes shows different components contained in or connected to other different components.It should be understood that the architecture described in this way is only some examples, and other numerous architectures for implementing the same function are actually all implementable.Conceptually, any arrangement of the components that realize the same function is effectively "associated", so that the desired function can be realized.Therefore, any two components that are combined here to realize a specific function can be considered to be "associated" with each other, so that the desired function will be realized, without considering architecture or intermediate components.Similarly, any two components associated in this way can also be considered to be "operably connected" or "operably coupled" to each other, so as to realize the desired function, and any two components that can be associated in this way can also be considered to be "operably coupled" to each other, so as to realize the desired function.About the specific example that can be operably coupled, include but are not limited to components that can be physically paired and / or physically interacted and / or components that can be wirelessly interacted and / or wirelessly interacted and / or components that can be logically interacted and / or components that can be logically interacted.

[0209] As for the use of substantially any plural and / or singular terms herein, those skilled in the art may appropriately convert from the plural to the singular and / or from the singular to the plural, depending on the context and / or application. For the sake of clarity, various singular / plural permutations may be explicitly set forth herein.

[0210] Those skilled in the art will understand that, in general, terms used herein, and particularly in the appended claims (e.g., the body of the appended claims), should generally be treated as "open" terms (for example, the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "comprising" should be interpreted as "including but not limited to," etc.). Those skilled in the art will further understand that if an introduced claim recitation is directed to a specific quantity, such intent should be expressly recited in the claim, and if such recitation is absent, such intent is absent. For example, if only one item is intended, the term "single" or similar language may be used. As an aid to understanding, subsequent appended claims and / or the description herein may include the use of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed as a way of introducing claim recitations by the indefinite article "a" or "an" to limit any particular claim containing claim recitations introduced in this manner to embodiments containing only one such recitation, even if the same claim contains the introductory phrases "one or more" or "at least one" and an indefinite article such as "a" or "an" (e.g., "a" and / or "an" should be construed to mean "at least one" or "one or more"). Furthermore, even if a specific number of claim recitations introduced is explicitly recited, one skilled in the art will recognize that such recitation should be construed to refer to at least the recited number (e.g., an unmodified recitation of "two recitations" without other modifiers means at least two recitations or two or more recitations). Furthermore, in these examples, if a convention similar to "at least one of A, B, and C, etc." is used, such a structure should generally have the meaning of the convention understood by those skilled in the art (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems having only A, only B, only C, A and B, A and C, B and C, and / or A, B, and C, etc.). In examples where a convention similar to "at least one of A, B, or C, etc." is used, such a structure should generally have the meaning of the convention understood by those skilled in the art (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems having only A, only B, only C, A and B, A and C, B and C, and / or A, B, and C, etc.). Those skilled in the art will further understand that almost any disjunctive word and / or phrase that proposes two or more alternatives, whether in the specification, claims, or drawings, should be understood to contemplate the possibility of including one, any, or both of these items.For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B." In addition, the term "any one" followed by a list of multiple items and / or multiple categories of items as used herein is intended to include "any one," "any combination," "any plurality," and / or "any combination of a plurality" of the items and / or categories of items, alone or in combination with other items and / or other categories of items. In addition, the terms "set" or "group" as used herein shall include any number of items, including zero. In addition, the term "number" as used herein is intended to include any number, including zero.

[0211] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is thereby described in terms of any individual member or subgroup of members of the Markush group.

[0212] Those skilled in the art will appreciate that, for any and all purposes (e.g., in providing a written description), all ranges disclosed herein also include any and all possible sub-ranges and combinations of sub-ranges thereof. Any range listed can be easily considered to fully describe and enable the same range to be decomposed into at least two equal parts, three equal parts, four equal parts, five equal parts, ten equal parts, etc. As a non-limiting example, each range discussed herein can be easily decomposed into a lower third, a middle third, and an upper third range. Those skilled in the art will appreciate that all languages ​​such as "at most", "at least", "greater than", "less than", etc. include the narrated numbers and refer to ranges that can be subsequently decomposed into sub-ranges as described above. Finally, as those skilled in the art understand, a range includes each individual member. Thus, for example, a group having 1-3 cells refers to a group having 1, 2, or 3 cells. Similarly, a group having 1-5 cells refers to a group having 1, 2, 3, 4, or 5 cells, and so on.

[0213] Furthermore, the claims should not be construed as limited to the described order or elements unless otherwise indicated. In addition, the term "means for..." used in any claim is intended to invoke 35 U.S.C. § 112, 6 or “means-plus-function” claim format, and any claim without the word “means” shall not have this meaning.

[0214] A processor in association with software may be used to implement a radio frequency transceiver for use in a wireless transmit receive unit (WTRU), user equipment (UE), terminal, base station, mobility management entity (MME) or evolved packet core (EPC) or any host computer. The WTRU may be used in conjunction with modules implemented in hardware and / or software, including software defined radios (SDRs) and other components such as cameras, video camera modules, video phones, speaker amplifiers, vibration devices, speakers, microphones, television transceivers, hands-free headsets, keyboards, module, a frequency modulation (FM) radio unit, a near field communication (NFC) module, a liquid crystal display (LCD) display unit, an organic light emitting diode (OLED) display unit, a digital music player, a media player, a video game console module, an Internet browser and / or any wireless local area network (WLAN) or ultra-wideband (UWB) module.

[0215] Although the present invention is described in terms of communication systems, it should be appreciated that these systems may also be implemented in software on a microprocessor / general purpose processor (not shown). In some embodiments, one or more functions of the various components may be implemented in software controlling a general purpose computer.

[0216] In addition, although specific embodiments are used to illustrate and describe the present invention, the present invention is not limited to the details shown. On the contrary, various modifications can be made in the details within the equivalent scope and scope of the claims and without departing from the scope of the present invention.

[0217] Typical embodiments

[0218] In a first exemplary embodiment, a typical apparatus for using at least one subchannel of a physical channel for uplink communication is provided, wherein the physical channel includes a resource set within a first channel boundary and a second channel boundary, whereby the physical channel includes a plurality of subchannels, each of which includes a subset of resources of the physical channel and has at least one subchannel boundary that does not overlap with the first or second channel boundary. The typical apparatus includes: a station (STA), including: a processor; and a transmitting / receiving unit, which is configured to: transmit control information including a subchannel SIG field indicating an identity of the STA via an uplink, receive a trigger frame indicating one or more subchannels that can be obtained from a plurality of subchannels, determine which subchannels of the one or more subchannels are to be obtained, and transmit data via an uplink and using the one or more obtained subchannels.

[0219] In a second typical embodiment, another typical device includes an access point (AP), which is configured to allocate subchannels of a physical channel for uplink communication of a station (STA), the physical channel including a set of resources within a first and a second channel boundary so that the physical channel includes multiple subchannels, each of which includes a resource subset of the physical channel and has at least one subchannel boundary that does not overlap with the first or second channel boundary, the AP includes: a transmitting / receiving unit, which is configured to: receive control information including a subchannel SIG field for indicating an identity of the station (STA) via an uplink, transmit a trigger frame to the STA for indicating one or more subchannels that can be obtained from multiple subchannels, and receive data via an uplink using the acquired one or more subchannels.

[0220] In a third typical embodiment, a typical method includes a method implemented by a station (STA) for using at least one subchannel in a physical channel for uplink communication, the method including: transmitting control information including a subchannel SIG field for indicating an identity of the STA via an uplink, receiving a trigger frame for indicating one or more subchannels that can be obtained from multiple subchannels, determining which subchannels of the one or more subchannels to obtain, and transmitting data via an uplink and using the obtained one or more subchannels.

[0221] In a fourth typical embodiment, another typical method includes a method implemented by an access point (AP) for allocating subchannels in a physical channel for uplink communication of a station (STA), the method comprising: receiving control information including a subchannel SIG field indicating an identity of the station (STA) via an uplink, transmitting a trigger frame to the STA indicating one or more subchannels that can be obtained from multiple subchannels, and receiving data via the uplink using the obtained one or more subchannels.

[0222] In a fifth typical embodiment, another typical apparatus includes a station (STA) configured to use at least one subchannel in a physical channel for uplink communication, the STA including: a processor configured to: obtain information about at least one neighboring STA, and a transmit / receive unit configured to: transmit information about the at least one neighboring STA, and receive (1) a group identity of a group including the STA; and (2) information indicating one or more subchannels among a plurality of subchannels allocated to the STA.

[0223] In a sixth typical embodiment, another typical device includes an access point (AP) configured to allocate subchannels in a physical channel to a first station (STA) among a plurality of STAs and one or more other STAs among the plurality of STAs, the AP including: a transmit / receive unit configured to: for each corresponding STA of the one or more STAs among the plurality of STAs: receive a report including information about one or more neighboring STAs of the corresponding STA; and a processor configured to: based on the received report, assign a group identifier to and allocate subchannels of the physical channel to a first STA and one or more other STAs that are group members of a multi-user group, wherein the transmit / receive unit may be configured to transmit at least (1) a group identifier and (2) allocation information associated with one or more subchannels to the first STA and the one or more other STAs that are group members of the multi-user group.

[0224] In a seventh exemplary embodiment, another exemplary method includes a method implemented by a station (STA) for grouping STAs into a multi-user group using at least one subchannel of a physical channel, the physical channel including a resource set, whereby the physical channel includes a plurality of subchannels, wherein each subchannel may include a subset of physical channel resources. The method may include: the STA acquiring information related to at least one neighboring STA, the STA transmitting information related to at least one neighboring STA to an AP, and the STA receiving: (1) a group identity of a group including the STA, and (2) information indicating one or more subchannels of the plurality of subchannels allocated to the STA.

[0225] In an eighth typical embodiment, another typical method includes a method implemented by an access point (AP) for allocating sub-channels of a physical channel to a first STA among multiple stations (STA) and one or more other STAs among the multiple STAs, the method including: for each corresponding STA among one or more STAs among the multiple STAs: receiving information including one or more neighboring STAs of the corresponding STA, assigning a group identifier to and allocating sub-channels of the physical channel to the first STA and one or more other STAs that are group members of a multi-user group based on the received report, and transmitting (1) the group identifier and (2) allocation information associated with one or more sub-channels to at least the first STA and the one or more other STAs that are group members of the multi-user group.

[0226] In the first exemplary embodiment, the processor is further configured to perform any of the following processes: initiating uplink data transmission or ending uplink data transmission on a sub-channel boundary that does not coincide with the first channel boundary or the second channel boundary.

[0227] In the first, second, third and fourth exemplary embodiments, the at least one sub-channel boundary is indicated by any one of a time value or a frequency value.

[0228] In the first, second, third and fourth exemplary embodiments, the respective subchannels comprise time / frequency resources, whereby a first set of subchannel boundaries constrains a subset of the time / frequency resources in time and a second set of subchannel boundaries constrains a subset of the time / frequency resources in frequency.

[0229] In a first exemplary embodiment, the transmitting / receiving unit is further configured to transmit the control information upon receiving another trigger frame indicating the start of the contention period.

[0230] In the first exemplary embodiment, the transmitting / receiving unit is further configured to transmit control information for indicating that the STA is capable of performing sub-channel allocation.

[0231] In the first exemplary embodiment, the transmit / receive unit is further configured to obtain a legacy preamble for reserving a transmission opportunity (TXOP) of the entire uplink frame from the received trigger frame.

[0232] In the first typical embodiment, the transmitting / receiving unit is further configured to obtain the duration of the AP transmission opportunity (TXOP) assigned or announced by the access point (AP) from the received trigger frame, and the TXOP duration is the duration for the STA to transmit data of a certain length.

[0233] In a first typical embodiment, the transmit / receive unit is configured to transmit a preamble prior to data communication, transmit a predefined or signaled number of data OFDMA symbols, and transmit a midamble after the predefined or signaled number of data OFDMA symbols have been transmitted.

[0234] In a first typical embodiment, a processor is configured to determine the availability of one or more subchannels after a preamble, and a transmit / receive unit is further configured to: acquire at least one subchannel of the one or more subchannels determined to be available for use by the processor, receive a subsequent trigger frame after a midamble, and transmit data using the acquired subchannel when a transmission opportunity (TXOP) duration of an access point (AP) has not yet been reached.

[0235] In the first exemplary embodiment, the processor is further configured to perform channel estimation.

[0236] In a first exemplary embodiment, the transmit / receive unit is further configured to determine one or more subchannels to be acquired after sending the preamble, and to acquire another one or more subchannels during or after transmitting the midamble.

[0237] In the second exemplary embodiment, a processor is further included, the processor being configured to perform any of the following processes: determining the start or end of uplink data transmission based on at least one sub-channel boundary that does not coincide with the first channel boundary or the second channel boundary.

[0238] In a second exemplary embodiment, the transmit / receive unit is further configured to receive further control information in case a further trigger frame indicating the start of a subsequent contention period is transmitted.

[0239] In a second typical embodiment, the processor is further configured to determine from the control information whether the STA has subchannel allocation capability; and generate a trigger frame: (1) when the STA has subchannel allocation capability, the trigger frame includes a first subchannel allocation for allocating one or more subchannels to the STA, or (2) when the STA does not have subchannel allocation capability, the trigger frame does not include a first subchannel allocation for allocating one or more subchannels to the STA.

[0240] In the second exemplary embodiment, the transmitting / receiving unit is further configured to transmit the generated trigger frame to the STA.

[0241] In the second exemplary embodiment, the transmitting / receiving unit is further configured to transmit a trigger frame including allocation information for allocating a transmission opportunity (TXOP) for the entire uplink frame to the STA if the STA does not have a subchannel allocation capability.

[0242] In a second exemplary embodiment, the processor is further configured to: determine a duration of a transmission opportunity (TXOP) for a STA; and generate a trigger frame including information indicating the determined duration; and the transmit / receive unit is further configured to transmit the trigger frame.

[0243] In a second exemplary embodiment, the transmit / receive unit is further configured to: transmit the first subchannel allocation after receiving the preamble; and transmit the second subchannel allocation during or after receiving the midamble.

[0244] In a third typical embodiment, the method may further include any one of the following: initiating uplink data transmission or ending uplink data transmission at a sub-channel boundary that does not coincide with the first sub-channel boundary or the second channel boundary.

[0245] In a third exemplary embodiment, transmitting the control information includes transmitting the control information upon receiving another trigger frame indicating the start of the contention period.

[0246] In the third exemplary embodiment, transmitting the control information includes transmitting control information for indicating that the STA has sub-channel allocation capability.

[0247] In a third exemplary embodiment, the method may further include obtaining a legacy preamble that reserves a transmission opportunity (TXOP) for the entire uplink frame from the received trigger frame.

[0248] In a third typical embodiment, the method may further include acquiring a duration of an AP transmission opportunity (TXOP) assigned or announced by an access point (AP) from a received trigger frame, wherein the duration of the TXOP is a duration for a STA to transmit data of a certain length.

[0249] In a third exemplary embodiment, the method may further include transmitting a preamble prior to data communication, transmitting a predefined or signaled number of data OFDMA symbols, and transmitting a midamble after the predefined or signaled number of data OFDMA symbols have been transmitted.

[0250] In a third typical embodiment, the method may further include determining the availability of one or more subchannels after the preamble, acquiring at least one subchannel of the one or more subchannels determined to be available for use by the processor, receiving a subsequent trigger frame after the midamble, and transmitting data using the acquired subchannel when the TXOP duration of the AP has not yet been reached.

[0251] In a third exemplary embodiment, the method may further include performing channel estimation.

[0252] In a third exemplary embodiment, the method may further include: determining one or more sub-channels to be acquired after sending the preamble, and acquiring another one or more sub-channels after transmitting the midamble.

[0253] In a fourth exemplary embodiment, the method may further include any one of the following: determining the start or end of uplink data transmission based on at least one sub-channel boundary that does not coincide with the first channel boundary or the second channel boundary.

[0254] In a fourth exemplary embodiment, the method may further include: receiving another control information in case another trigger frame indicating the start of a subsequent contention period is transmitted.

[0255] In a fourth typical embodiment, the method may further include: determining from control information whether the STA has subchannel allocation capability; and generating a trigger frame: (1) when the STA has subchannel allocation capability, the trigger frame includes a first subchannel allocation for allocating one or more subchannels to the STA, or (2) when the STA does not have subchannel allocation capability, the trigger frame does not include a first subchannel allocation for allocating one or more subchannels to the STA.

[0256] In a fourth exemplary embodiment, the method may further include: transmitting the generated trigger frame to the STA.

[0257] In a fourth exemplary embodiment, in a case where the STA does not have a subchannel allocation capability, transmitting the trigger frame includes transmitting the trigger frame including allocation information for allocating a transmission opportunity (TXOP) with respect to the entire uplink frame to the STA.

[0258] In a fourth exemplary embodiment, the method may further include determining a duration of a transmission opportunity (TXOP) of the STA, generating a trigger frame including information indicating the determined duration, and transmitting the trigger frame.

[0259] In a fourth exemplary embodiment, the method may further include transmitting the first sub-channel allocation after receiving the preamble, and transmitting the second sub-channel allocation during or after receiving the midamble.

[0260] In the fifth exemplary embodiment, the resource set included in the physical channel is time / frequency resources.

[0261] In a fifth exemplary embodiment, the processor is further configured to transmit data according to the group identity and one or more sub-channels among the plurality of sub-channels allocated to the STA.

[0262] In a fifth exemplary embodiment, the transmit / receive unit is configured to receive a discovery frame transmitted by at least one neighboring STA, and the processor is configured to determine information about the at least one neighboring STA based on information associated with the discovery frame.

[0263] In the fifth exemplary embodiment, the information associated with the discovery frame includes any one of: (1) information included in the discovery frame; and / or (2) metrics associated with the discovery frame.

[0264] In the fifth exemplary embodiment, the discovery frame includes information for indicating any one of the following: (1) the STA is a legacy STA and / or (2) the STA performs an Orthogonal Frequency Division Multiple Access (OFDMA) operation.

[0265] In a fifth typical embodiment, the transmit / receive unit is configured to receive a discovery frame containing information related to a neighboring STA, wherein the information is any one of: (1) location information associated with at least one neighboring STA, (2) power level information associated with the at least one neighboring STA, (3) direction information associated with the at least one neighboring STA, or (4) speed information associated with the at least one neighboring STA, and the processor is configured to determine a group identity based on the information associated with the neighboring STA.

[0266] In a fifth typical embodiment, the transmit / receive unit is configured to receive a filter condition indicating a criterion for processing information about at least one neighboring STA, and the processor is configured to store and / or transmit information about the at least one neighboring STA based on information associated with the received discovery frame when the criterion indicated by the filter condition is met.

[0267] In the fifth exemplary embodiment, information on at least one neighboring STA is transmitted as a Neighbor Report Element.

[0268] In a fifth typical embodiment, the neighbor report element includes one or more of information about neighbors included in a basic subscriber set (BSS) of the STA and information about neighbors included in one or more neighboring BSSs, and the information about neighbors included in the BSS and the information about neighbors included in the neighboring BSSs respectively include information associated with the neighboring STA about at least one neighbor.

[0269] In a sixth typical embodiment, the processor is configured to assign STAs that are located close to each other into a multi-user group based on information associated with the neighboring STAs: the information is any one of the following: (1) location information associated with the at least one neighboring STA, (2) power level information associated with the at least one neighboring STA, (3) direction information associated with the at least one neighboring STA, or (4) speed information associated with the at least one neighboring STA contained in the received report.

[0270] In a sixth exemplary embodiment, the processor is configured to assign mutually interfering STAs from one or more overlapping BSSs (OBSSs) into a multi-user group based on information included in the received reports.

[0271] In a sixth exemplary embodiment, the transmit / receive unit is configured to send a discovery frame including information associated with any of: (1) an AP, or (2) one or more neighboring STAs.

[0272] In the sixth exemplary embodiment, each of the received reports includes a neighbor report element having information for indicating any one of the following: (1) the corresponding STA is a legacy STA; or (2) the corresponding STA performs orthogonal frequency division multiple access (OFDMA) operation.

[0273] In the seventh exemplary embodiment, the resource set included in the physical channel is time / frequency resources.

[0274] In a seventh exemplary embodiment, the method further comprises transmitting data according to the group identity and one or more sub-channels among the plurality of sub-channels allocated to the STA.

[0275] In the seventh exemplary embodiment, the method further includes receiving a discovery frame transmitted by at least one neighboring STA, and determining information about the at least one neighboring STA based on information associated with the discovery frame.

[0276] In the seventh exemplary embodiment, the information associated with the discovery frame includes any one of the following: (1) information included in the discovery frame, or (2) a metric associated with the discovery frame.

[0277] In the seventh exemplary embodiment, the discovery frame includes information for indicating any one of the following: (1) the STA is a legacy STA, or (2) the STA performs an orthogonal frequency division multiple access (OFDMA) operation.

[0278] In a seventh typical embodiment, the method further includes: receiving a discovery frame including information associated with a neighboring STA, wherein the information is any one of the following: (1) location information associated with the at least one neighboring STA, (2) power level information associated with the at least one neighboring STA, (3) direction information associated with the at least one neighboring STA, or (4) speed information associated with the at least one neighboring STA, and determining the group identity based on the information associated with the neighboring STA.

[0279] In a seventh typical embodiment, the method further includes: receiving a filtering condition, wherein the filtering condition indicates a criterion for processing information about the at least one neighboring STA, and based on information associated with the received discovery frame, storing or transmitting information about the at least one neighboring STA when the criterion indicated by the filtering condition is met.

[0280] In an eighth typical embodiment, the method further includes: assigning STAs that are located close to each other into a multi-user group based on information associated with the neighboring STAs, wherein the information is any one of the following: (1) location information associated with the at least one neighboring STA, (2) power level information associated with the at least one neighboring STA, (3) direction information associated with the at least one neighboring STA, or (4) speed information associated with the at least one neighboring STA contained in the received report.

[0281] In an eighth exemplary embodiment, the method further comprises assigning mutually interfering STAs from one or more overlapping BSSs (OBSSs) into a multi-user group based on information contained in the received inclusion.

[0282] In an eighth exemplary embodiment, the method further comprises: transmitting a discovery frame including information associated with any one of: an AP and / or one or more neighboring STAs.

[0283] In the eighth exemplary embodiment, each of the received reports includes a neighbor report element having information for indicating any one of the following: (1) the corresponding STA is a legacy STA; or (2) the corresponding STA performs orthogonal frequency division multiple access (OFDMA) operation.

Claims

1. First Station (STA), including: transceiver; as well as The processor is configured as: receiving, via the transceiver, a plurality of packets from a plurality of second STAs; Determine one or more neighbor STAs from among the plurality of second STAs located in a geographically adjacent area to the first STA; Determining the neighbor information associated with each of the one or more neighbor STAs by extracting neighbor information from corresponding packets received from the one or more neighbor STAs, the neighbor information comprising one or more of: an identifier associated with a basic service set (BSS), a medium access control (MAC) address, a BSS color, or a power indication; assigning the one or more neighbor STAs to a multi-user (MU) group based on the one or more neighbor STAs having a specific BSS color; as well as Information associated with neighbor STAs in the assigned MU group that sense one or more fourth STAs in an overlapping BSS (OBSS) is sent to the third STA via the transceiver. 2 . The first STA of claim 1 , wherein the processor is further configured to send a discovery frame to the one or more neighbor STAs via the transceiver. 3 . The first STA according to claim 2 , wherein the discovery frame indicates one or more of the following: a BSS identifier, a STA identifier, a filter condition field, a power field, or an allocated resource field.

4. The first STA of claim 2, wherein the power field comprises a receive power threshold level for requesting a response from the one or more second STAs within the geographic proximity of the first STA. The first STA according to claim 2 , wherein the discovery frame is transmitted periodically.

6. The first STA according to claim 1, wherein the processor is configured to: Determine a received power level associated with each of the plurality of groups, wherein the one or more neighbor STAs are determined to be located within the geographic proximity to the first STA based on the received power level being above a predetermined threshold, wherein the predetermined threshold is determined based on one or more of a transmit frequency bandwidth or a transmit power indication.

7. The first STA according to claim 6, wherein the processor is configured to send one or more neighbor information fields, wherein each of the one or more neighbor information fields indicates the neighbor information for a corresponding neighbor STA of the one or more neighbor STAs.

8. The first STA according to claim 1, wherein the third STA is in the OBSS. 9 . The first STA of claim 1 , wherein each of the one or more neighbor STAs in the MU group is in the same BSS.

10. The first STA according to claim 1, wherein the processor is configured to: receiving a resource allocation in response to sending the neighbor report frame; and An uplink OFDMA transmission is sent via the transceiver using one or more resources indicated in the resource allocation.

11. A method performed by a first station (STA), the method comprising: receiving a plurality of packets from a plurality of second STAs; Determine one or more neighbor STAs from among the plurality of second STAs located in a geographically adjacent area to the first STA; Determining the neighbor information associated with each of the one or more neighbor STAs by extracting neighbor information from corresponding packets received from the one or more neighbor STAs, the neighbor information comprising one or more of: an identifier associated with a basic service set (BSS), a medium access control (MAC) address, a BSS color, or a power indication; assigning the one or more neighbor STAs to a multi-user (MU) group based on the one or more neighbor STAs having a specific BSS color; as well as Information associated with neighbor STAs in the assigned MU group that sense one or more fourth STAs in an overlapping BSS (OBSS) is sent to the third STA via the transceiver. 12 . The method of claim 11 , further comprising sending a discovery frame to the one or more neighbor STAs.

13. The method of claim 12, wherein the discovery frame indicates one or more of: a BSS identifier, a STA identifier, a filter condition field, a power field, or an allocated resources field.

14. The method of claim 12, wherein the power field comprises a receive power threshold level for requesting a response from the one or more second STAs within the geographic proximity of the first STA. The method of claim 12 , wherein the discovery frame is sent periodically.

16. The method of claim 11, further comprising determining a received power level associated with each of the plurality of groups, wherein the one or more neighbor STAs are determined to be located within the geographic proximity to the first STA based on the received power level being above a predetermined threshold, wherein the predetermined threshold is determined based on one or more of a transmit frequency bandwidth or a transmit power indication. 17 . The method of claim 16 , further comprising transmitting one or more neighbor information fields, wherein each of the one or more neighbor information fields indicates the neighbor information for a corresponding neighbor STA of the one or more neighbor STAs. The method according to claim 11 , wherein the third STA is in the OBSS.

19. The method of claim 11, wherein each of the one or more neighbor STAs in the MU group is in the same BSS.

20. The method according to claim 11, further comprising: receiving a resource allocation in response to sending the neighbor report frame; as well as An uplink OFDMA transmission is sent using the one or more resources indicated in the resource allocation.

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