Terminal device, base station device, and communication method

Abstract

This terminal device comprises a reception unit that receives a frame. The frame includes a UHR operation element, and UHR STA is controlled by the UHR operation element. The UHR operation element includes a first field, and the first field indicates whether NPCA is enabled. When the first field indicates that NPCA is enabled, NPCA may be performed.

Description

Terminal device, base station device, and communication method

[0001] The present invention relates to a terminal device, a base station device, and a communication method.This application claims priority to Japanese Patent Application No. 2024-101456, filed on June 24, 2024, the contents of which are incorporated herein by reference.

[0002] The Institute of Electrical and Electronics Engineers Inc. (IEEE) is currently studying ways to increase the speed and efficiency of frequency usage in wireless LAN (Local Area Network) communications. Currently, standardization of IEEE802.11bn, the successor to IEEE802.11be, has begun.

[0003] One aspect of the present invention provides a terminal device, a base station device, and a communication method that enable efficient communication.

[0004] (1) A first aspect of the present invention is a terminal device comprising a receiving unit that receives a frame, the frame including a UHR operation element, a UHR STA controlled by the UHR operation element, the UHR operation element including a first field, the first field indicating whether NPCA is enabled, and the terminal device may perform NPCA if the first field indicates that NPCA is enabled.

[0005] (2) A second aspect of the present invention is a base station device including a transmitter that transmits a frame, the frame including a UHR operation element, a UHR STA being controlled by the UHR operation element, the UHR operation element including a first field, the first field indicating whether NPCA is enabled, and if the first field indicates that NPCA is enabled, the base station device may perform NPCA.

[0006] (3) A third aspect of the present invention is a communication method used in a terminal device, comprising the step of receiving a frame, the frame including a UHR operation element, a UHR STA being controlled by the UHR operation element, the UHR operation element including a first field, the first field indicating whether NPCA is enabled, and if the first field indicates that NPCA is enabled, the communication method may perform NPCA.

[0007] An efficient wireless communication system can be realized.

[0008] FIG. 1 is a diagram illustrating an example of a wireless LAN system according to an aspect of the present embodiment. FIG. 2 is a diagram illustrating an example of an OBSS according to an aspect of the present embodiment. FIG. 3 is a diagram illustrating an example of a configuration of an STA according to an aspect of the present embodiment. FIG. 4 is a diagram illustrating an example of a configuration of an AP according to an aspect of the present embodiment. FIG. 5 is a diagram illustrating an example of a MAC frame format according to an aspect of the present embodiment. FIG. 6 is a diagram illustrating an example of an A-MSDU according to an aspect of the present embodiment. FIG. 7 is a diagram illustrating an example of an A-MPDU according to an aspect of the present embodiment. FIG. 8 is a diagram illustrating an example of fragmentation according to an aspect of the present embodiment. FIG. 9 is a diagram illustrating an example of a PPDU according to an aspect of the present embodiment. FIG. 10 is a diagram illustrating an example of a backoff procedure according to an aspect of the present embodiment. FIG. 11 is a diagram illustrating an example of a NAV according to an aspect of the present embodiment. FIG. 12 is a diagram illustrating an example of channel bonding according to an aspect of the present embodiment. FIG. 13 is a diagram illustrating an example of a backoff procedure on an NPCA primary channel of a STA according to an aspect of the present embodiment. FIG. 14 is a diagram illustrating an example of processing related to NAV update according to an aspect of the present embodiment.

[0009] Hereinafter, an embodiment of the present invention will be described.

[0010] "A and / or B" may be a term that includes "A", "B", or "A and B".

[0011] The wireless LAN system in this embodiment includes an access point (AP) and stations (STAs). A network consisting of the access point and stations is called a basic service set (BSS). The wireless LAN system may be composed of one or more stations. When the wireless LAN system is composed of two or more STAs, the wireless LAN system may be called a BSS.

[0012] An access point (AP) may be referred to as a base station device, and a station (STA) may be referred to as a terminal device.

[0013] Fig. 1 is a diagram showing an example of a wireless LAN system according to an aspect of the present embodiment. In Fig. 1, the wireless LAN system includes STA 103, STA 104, and AP 102. 101 may also be referred to as BSS.

[0014] An STA may be a logical entity that is a single addressable instance of a Medium Access Control (MAC) and physical layer interface to a wireless medium (WM). An STA may also be a communication device over a wireless medium. An STA may also include an Access Point (AP) with base station functionality and / or a non-AP STA with terminal functionality. That is, an STA may be an AP. An STA may also be a non-AP STA. An STA may also refer to both an AP and a non-AP STA. An STA may also be referred to as a terminal device.

[0015] The wireless medium may be a medium used to implement the transfer of Protocol Data Units (PDUs) between peer physical layer entities of a Wireless LAN. The wireless medium may also be referred to as a medium. The medium may also be referred to as a Medium.

[0016] A channel may be an instance of a wireless medium used to transmit PPDUs between two or more STAs.

[0017] An AP may be an entity that contains one STA and provides associated STA(s) access to distribution system services (DSS) over a wireless medium. An AP may include a STA and a distribution system access function (DSAF). An AP may also be referred to as an STA. That is, an AP may also be an STA.

[0018] A non-AP STA (non-access point station) may be a STA that is not included in an AP. For example, a non-AP STA may be an HT STA. A non-AP STA may be a VHT STA. A non-AP STA may be an HE STA. A non-AP STA may be an EHT STA. A non-AP STA may be a UHR STA. A non-AP STA may be a STA other than the aforementioned STAs. A non-AP STA may also be referred to as an STA.

[0019] Distribution system services may be the set of services provided by a distribution system (DS). A distribution system access function may be a function within an AP that provides access between the distribution system and the wireless medium using MAC services and distribution system services. A distribution system may be a system used to interconnect a set of BSSs and an integrated LAN to create an Extended Service Set (ESS).

[0020] A BSS may be a set of STAs that have successfully synchronized using JOIN service primitives and one STA that has used a START primitive. For example, MLME-JOIN.confirm may be used as the JOIN service primitive. MLME-JOIN.confirm may be a primitive for confirming synchronization with the BSS. MLME-JOIN.request may be used as the JOIN service primitive. MLME-JOIN.request may be a primitive for requesting synchronization with the BSS. For example, MLME-START.request may be used as the START primitive. MLME-START.request may be a primitive for requesting that a MAC entity start a new BSS. A primitive may be an internal signal in a STA or AP. The internal signal here may be an internal signal used for information exchange between entities in different layers or different protocols, such as between an SME and an MLME, between an SME and a PLME, or between an MLME and a PLME.

[0021] An ESS may be a set of one or more interconnected BSSs that appear as a single BSS at the Logical Link Control (LLC) layer of a STA associated with any of these BSSs. An ESS (Extended Service Set) may have a connection path between one of the APs that are members of the ESS and a non-AP STA via a WM. An ESS may have overlapping communication areas (coverage) formed by multiple BSSs. An ESS may have multiple BSSs separated by a large distance, or may arrange the coverage areas of multiple BSSs as a larger coverage area. In other words, the communication area of ​​an ESS may be the same as or larger than the communication area of ​​a single BSS. A communication area formed by an ESS may be referred to as an Extended Service Area (ESA).

[0022] An Overlapping Basic Service Set (OBSS) may be a BSS that operates on the same channel as the STA's BSS and within (partially or entirely) its Basic Service Area (BSA).

[0023] FIG. 2 is a diagram illustrating an example of an OBSS according to one aspect of the present embodiment. In FIG. 2, 202 may be AP#1. 203 may be STA#1. 204 may be STA#2. 201 may be BSS#1 composed of 202, 203, and 204. 203 may be synchronized with 202. 204 may be synchronized with 202. 206 may be AP#2. 207 may be STA#3. 208 may be STA#4. 205 may be BSS#2 composed of 206, 207, and 208. 207 may be synchronized with 206. 208 may be synchronized with 206. 202 may not be synchronized with 207. 202 may not be synchronized with 208. 206 may not be synchronized with 203. 206 may not be synchronized with 204. 201 and 205 may be BSSs operating on the same channel. 205 may be considered an OBSS by 201. 201 may be considered an OBSS by 205. For example, 202 may receive a frame transmitted by 207. 204 may receive a frame transmitted by 207. 207 may receive a frame transmitted by 202. 207 may receive a frame transmitted by 204. For example, 202 may determine that the channel is busy while 207 is transmitting. 204 may determine that the channel is busy while 207 is transmitting. 207 may determine that the channel is busy while 202 is transmitting. 207 may determine that the channel is busy while 204 is transmitting.

[0024] A BSA may be a region that includes members of a BSS. A BSA may also include members of other BSSs. For example, in Figure 2, 201 may be a BSA that includes 203, 204, and 207, where 207 may be a member of another BSS.

[0025] An IBSS (Independent Basic Service Set) is a BSS that forms a self-contained network and does not provide access to the DS.

[0026] An addressable unit may be a station (STA). Physical and operational characteristics may be defined by modifiers placed before the STA term. For example, in the case of location and mobility, addressable units may be fixed STA, mobile STA, and mobility STA. A STA is an addressable destination, but may not (generally) have a fixed location. A STA may have multiple different characteristics, each of which may shape its function. For example, a single addressable unit may simultaneously have the characteristics of a portable STA, a QoS STA, a dependent STA, and a hidden STA.

[0027] The architecture may consist of several components that interact to provide a WLAN that supports STA mobility transparently to higher layers. A BSS may be a fundamental building block of a LAN. The range over which member STAs of a BSS can communicate may be considered a coverage area. The set of all possible directional transmissions by member STAs may be referred to as a BSA.

[0028] Physical limitations may determine the distance between direct STAs. An infrastructure BSS may be part of a network consisting of multiple BSSs. The architecture component for interconnecting infrastructure BSSs may be a DS for non-General Link (non-GLK) operation. DS and Extended Service Sets (ESSs) may be mechanisms for extending connectivity for non-GLK operation. GLK operation may involve the use of bridges to form an extended network. The wireless medium and Distribution System Medium (DSM) may be logically separated. Each logical medium may be used for different purposes by different components of the architecture. Recognizing that multiple media are logically distinct is important to understanding the flexibility of the architecture. The LAN architecture is specified independently of the physical characteristics of a particular implementation. A Distribution System (DS) may enable support for mobile devices by providing the logical services necessary for address-to-destination mapping and seamless integration of multiple BSSs. An AP is an entity with STA functionality and a Distribution System Access Function (DSAF) that may enable associated STAs to access the Distribution System (DS) over the wireless medium. Data between the BSS and Distribution System (DS) may travel via the Distribution System Access Function (DSAF) within the AP. An AP may contain STAs, addressable on the wireless medium using their STA addresses. The addresses an AP uses to communicate on the wireless medium and on the DSM may not necessarily be the same. Data sent from one of the STAs associated with an AP addressed to the AP's STA address may always be received on an uncontrolled port and processed by a port access entity. If a controlled port is authorized, the frame may conceptually pass through the DS.

[0029] A wireless network of any size and complexity may be constructed using a DS and an infrastructure BSS. This network may be referred to as an ESS (Extended Service Set). An ESS is a collection of infrastructure BSSs connected by the same SSID and may be connected by a DS. An ESS may not include a DS. An ESS may appear the same as an IBSS to the LLC layer. STAs within an ESS can communicate, and mobile STA(s) may move between BSSs (within the same ESS) transparently to the LLC. In an ESS, BSSs may partially overlap. This may be commonly used to allocate coverage within a physical range. In an ESS, BSSs may be physically separated. In an ESS, there may be no logical limit on the distance between BSSs. In an ESS, BSSs may be physically co-located. This may be done to provide redundancy. In an ESS, one or more IBSSs or ESSs may be physically co-located with one or more ESSs.

[0030] 3 is a diagram illustrating an example of the device configuration of an STA according to one aspect of this embodiment. The STA may include an antenna unit SU1, an RF (Radio Frequency) unit SU2, a physical layer processing unit (PHY layer processing unit) SU3, a MAC layer processing unit SU4, and an upper layer packet processing unit SU5. The STA may also include a radio transceiver unit SU6 and a frame processing unit SU7. The radio transceiver unit SU6 may be configured to include the antenna unit SU1 and the RF unit SU2. The frame processing unit SU7 may be configured to include the physical layer processing unit SU3 and the MAC layer processing unit SU4. The RF unit SU2 receives radio signals via the antenna unit SU1.

[0031] The signal received by the RF unit SU2 is converted into a baseband signal and sent to the physical layer processing unit SU3. The physical layer processing unit SU3 performs processing related to the physical layer function (PHY function) on the converted baseband signal. The signal that has undergone physical layer processing in the physical layer processing unit SU3 is sent to the MAC layer processing unit SU4. The MAC layer processing unit SU4 performs processing related to the MAC layer function (MAC function) on the baseband signal. The signal that has undergone MAC layer processing in the MAC layer processing unit SU4 is sent as an upper layer packet to the upper layer packet processing unit SU5. The upper layer packet processing unit SU5 performs processing related to the upper layer function on the upper layer packets extracted from the received signal.

[0032] The upper layer packet processing unit SU5 performs processing related to upper layer functions when transmitting an upper layer packet. The upper layer packet to be transmitted is sent from the upper layer packet processing unit SU5 to the MAC layer processing unit SU4. The MAC layer processing unit SU4 performs processing related to MAC layer functions on the upper layer packet. A frame that has undergone MAC layer processing in the MAC layer processing unit SU4 (a frame generated by processing the upper layer packet) is sent to the physical layer processing unit SU3. The physical layer processing unit SU3 performs processing related to physical layer functions on the frame that has undergone MAC layer processing. The frame sent from the physical layer processing unit SU3 to the RF unit SU2 is converted into an RF signal and transmitted as a radio signal via the antenna unit SU1.

[0033] The processing of the physical layer processing unit SU3 may be controlled by a Physical Layer Management Entity (PLME), which is an entity that controls the physical layer. The processing of the MAC processing unit SU4 may be controlled by a MAC Layer Management Entity (MLME), which is an entity that controls the MAC layer. The PLME and MLME provide their own layer management service interfaces. The PLME and MLME may also be controlled by a Station Management Entity (SME), which is an entity independent of the layers. The PLME, MLME, and SME may be included in the frame processing unit SU7.

[0034] 4 is a diagram illustrating an example of the device configuration of an AP according to one aspect of this embodiment. The AP may include an antenna unit AU1, an RF unit AU2, a physical layer processing unit AU3, a MAC layer processing unit AU4, and a DSAF unit AU5. The DSAF unit AU5 may have an upper layer packet processing function. The AP may also include a wireless transceiver unit AU6 and a frame processing unit AU7. The wireless transceiver unit AU6 may be configured to include the antenna unit AU1 and the RF unit AU2. The frame processing unit AU7 may be configured to include the physical layer processing unit AU3 and the MAC layer processing unit AU4.

[0035] The signal received by the RF unit AU2 is converted into a baseband signal and sent to the physical layer processing unit AU3. The physical layer processing unit AU3 performs processing related to physical layer functions on the converted baseband signal. The signal that has undergone physical layer processing in the physical layer processing unit AU3 is sent to the MAC layer processing unit AU4. The MAC layer processing unit AU4 performs processing related to MAC layer functions on the baseband signal. The signal that has undergone MAC layer processing in the MAC layer processing unit AU4 is sent to the DSAF unit AU5 as an upper layer packet. The DSAF unit AU5 performs processing related to upper layer functions on the upper layer packets extracted from the received signal. The DSAF unit AU5 may also provide the upper layer packets to the DS.

[0036] The DSAF unit AU5 may acquire upper layer packets from the DS. The DSAF unit AU5 performs processing related to upper layer functions when transmitting upper layer packets. The upper layer packets to be transmitted are sent from the DSAF unit AU5 to the MAC layer processing unit AU4. The MAC layer processing unit AU4 performs processing related to MAC layer functions on the upper layer packets. A frame that has undergone MAC layer processing in the MAC layer processing unit AU4 (a frame generated by processing the upper layer packet) is sent to the physical layer processing unit AU3. The physical layer processing unit AU3 performs physical layer function processing on the frame that has undergone MAC layer processing. The frame sent from the physical layer processing unit AU3 to the RF unit AU2 is converted into an RF signal and transmitted as a wireless signal via the antenna unit AU1.

[0037] The processing of the physical layer processing unit AU3 may be controlled by the PLME. The processing of the MAC processing unit AU4 may be controlled by the MLME. The PLME and MLME may also be controlled by an SME, which is an entity independent of the layers. The PLME, MLME, and SME may be included in the frame processing unit AU7.

[0038] A High-Throughput STA (HT STA) may provide PHY and MAC functionality capable of supporting a throughput of 100 Mb / s or more as measured at the MAC data service access point (SAP). HT STAs may also be QoS STAs. HT features may be utilized by HT STAs associated with a High-Throughput AP (HT AP). A subset of HT features may be used between two HT STAs that are members of the same IBSS. Some PHY features that distinguish HT STAs from non-HT STAs may be multiple-input multiple-output (MIMO) operation, spatial multiplexing (SM), spatial mapping (including transmit beamforming), space-time block coding (STBC), low-density parity check (LDPC) coding, and antenna selection (ASEL). PPDU formats permitted by HT STAs may be non-HT format, HT-mixed format, and HT-greenfield format. In HT STAs, PPDUs may be transmitted in a 20 MHz bandwidth. In HT STAs, PPDUs may be transmitted in a 40 MHz bandwidth. HT STAs may have MAC functionality including frame aggregation, several block ack features, Power Save Multi-Poll (PSMP) operation, reverse direction (RD), and protection mechanisms to support coexistence with non-HT STAs.

[0039] A VHT STA (Very High-Throughput STA) may be an HT STA that supports VHT functions in addition to the functions supported by an HT STA. The primary PHY function of the VHT STA may support 40 MHz and 80 MHz channel widths. The primary PHY function of the VHT STA may support VHT single-user (SU) PPDUs. The primary PHY function of the VHT STA may support 160 MHz and 80+80 MHz channel widths. The primary PHY function of the VHT STA may support VHT multi-user (MU) PPDUs. The primary PHY function of the VHT STA may not be present in an HT STA. The primary MAC function of the VHT STA may support A-MPDU padding of VHT PPDUs. The primary MAC function of the VHT STA may support S-MPDU. The primary MAC function of the VHT STA may support bandwidth indication responses. The primary MAC function of the VHT STA may not be present in an HT STA. VHT functionality may be utilized by a VHT STA associated with a Very High-Throughput AP (VHT AP). A subset of VHT functionality may be used between two VHT STAs that are members of the same IBSS.

[0040] A High Efficiency (HE) STA may be a VHT STA when operating in the 5 GHz band. A 20 MHz-only HE STA may not support 40 MHz and 80 MHz channel widths. Support for a 20 MHz operating channel width may be mandatory for an HE STA. A 20 MHz-only non-AP HE STA may be required to support 40 MHz and 80 MHz operating channel widths. Support for 160 MHz and 80+80 MHz operating channel widths may be optional for an HE STA. An HE STA may also be an HT STA. A primary PHY feature of an HE STA that is not present in an HT or VHT STA may be support for DL ​​and UL OFDMA (Uplink Orthogonal Frequency Division Multiple Access). A primary PHY feature of an HE STA that is not present in an HT or VHT STA may be support for DL ​​MU-MIMO (Downlink Multi-User Multiple Input Multiple Output) with an HE AP supporting four or more spatial streams when MU-MIMO is performed across the entire PPDU bandwidth. A primary PHY function of an HE STA that is not present in an HT STA or VHT STA may be support for DL ​​MU-MIMO reception for non-AP HE STAs. A primary MAC function of an HE STA that is not present in an HT STA or VHT STA may be support for an AP's OMI (Operating Mode Indication) responder and OMI initiator. A primary MAC function of an HE STA that is not present in an HT STA or VHT STA may be support for an AP's individual TWT (Target Wake Time).A key MAC function of an HE STA that is not present in an HT STA or a VHT STA may be support for two NAV operation for non-AP STAs.

[0041] An Extreme High Throughput (EHT) STA may operate in the band between 1 GHz and 7.250 GHz. For example, an EHT STA may be an HE STA in 5 GHz and 6 GHz. For example, an EHT STA may be an HE STA in 2.4 GHz. An EHT STA may use operation elements for HT and / or VHT and / or HE STA.

[0042] An Ultra High Reliability (UHR) STA may operate in a band between 1 GHz and 7.250 GHz. For example, a UHR STA may be an EHT STA in 5 GHz and 6 GHz. For example, a UHR STA may be an HE STA in 5 GHz and 6 GHz. For example, a UHR STA may be a VHT STA in 5 GHz and 6 GHz. For example, a UHR STA may be an HE STA in 2.4 GHz. For example, a UHR STA may be an HT STA in 2.4 GHz. A UHR STA may support Non Primary Channel Access. A UHR STA may use operation elements for HT, VHT, HE, and / or UHR STAs. That is, a UHR STA may be controlled by an HT operation element, a VHT operation element, a HE operation element, an EHT operation element, and / or a UHR operation element. The UHR STA may receive information related to Non-Primary Channel Access transmitted from the AP. The UHR STA may receive information related to Non-Primary Channel Access transmitted from other STAs.

[0043] The APs and STAs within a BSS may transmit based on Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA), which may be a protocol designed to reduce the probability of collisions between multiple STAs accessing the medium at the most likely points.

[0044] An HT BSS may be a BSS in which a beacon frame transmitted by an HT STA includes an HT Capabilities element. A VHT BSS may be a BSS in which a beacon frame transmitted by a VHT STA includes a VHT Operation element. An HE BSS may be a BSS in which a beacon frame transmitted by an HE STA includes an HE Operation element. An EHT BSS may be a BSS in which a beacon frame transmitted by an HE STA includes an EHT Operation element. For example, an HT BSS may be configured with STAs supporting the HT STA capability. For example, a VHT BSS may be configured with STAs supporting the VHT STA capability. For example, an HE BSS may be configured with STAs supporting the HE capability. For example, an EHT BSS may be configured with STAs supporting the EHT capability.

[0045] In this embodiment, the STA may be, for example, an HT STA, a VHT STA, an HE STA, an EHT STA, or a UHR STA. The STA may be a STA other than the above-mentioned STAs.

[0046] The AP and STA may transmit frames of multiple frame types with a common frame format, which may be defined at the physical layer, MAC layer, and Logical Link Control (LLC) layer.

[0047] A MAC frame may be a unit of data exchanged between MAC entities. A synonym for a MAC frame may be MPDU. A MAC Protocol Data Unit (MPDU) may be a unit of data exchanged between two peer MAC entities using a physical layer (PHY) data service. A synonym for an MPDU may be MAC frame. A MAC Service Data Unit (MSDU) may be information delivered as a single unit between MAC Service Access Points (SAPs). A MAC frame in a STA may be processed by a MAC layer processing unit SU4. A MAC frame in a STA may be processed by a frame processing unit SU7. A MAC frame in an AP may be processed by a MAC layer processing unit AU4. A MAC frame in an AP may be processed by a frame processing unit AU7.

[0048] A PHY frame may be a unit of data exchanged between PHY entities. A synonym for a PHY frame may be a PPDU. A PPDU (PHY Protocol Data Unit) may be a unit of data exchanged between two peer PHY entities using a physical layer (PHY) data service. A synonym for a PPDU may be a PHY frame. A PHY frame in a STA may be processed by a physical layer processing unit SU4. A PHY frame in a STA may be processed by a frame processing unit SU7. A PHY frame in an AP may be processed by a physical layer processing unit AU4. A PHY frame in an AP may be processed by a frame processing unit AU7.

[0049] The MAC frame format may consist of a MAC header, a Frame body, and an FCS. The MAC frame format may consist of a set of fields that occur in a fixed order in every frame.

[0050] The MAC header may be composed of a Frame Control field, a Duration / ID field, an Address 1 field, an Address 2 field, an Address 3 field, a Sequence Control field, an Address 4 field, a QoS Control field, an HT Control field, etc. The MAC header may be composed of all of the above fields. The MAC header may be composed of some of the above fields.

[0051] Fig. 5 is a diagram showing an example of a MAC frame format according to one aspect of this embodiment. In Fig. 5, the MAC frame format may be composed of a MAC header, a Frame Body, and an FCS. In Fig. 5, the MAC header may be composed of a Frame Control field, a Duration field, an Address 1 field, an Address 2 field, an Address 3 field, a Sequence Control field, an Address 4 field, and a QoS Control field. The MAC frame format may be an MPDU.

[0052] The Frame Control field of the MAC header may be composed of subfields such as the Protocol Version subfield, Type subfield, Subtype subfield, To DS subfield, From DS subfield, More Fragments subfield, Retry subfield, Power Management subfield, More data subfield, Protected Frame subfield, +HTC subfield, Control Frame Extension subfield, Compressed SSID Present subfield, ANO Present subfield, BSS BW subfield, Security subfield, and AP PM subfield. The Frame Control field of the MAC header may be composed of some of the above subfields. The Frame Control field of the MAC header may be composed of all of the above subfields. The Frame Control field of the MAC header may be composed of a specific combination of subfields depending on the frame type.

[0053] The type of frame may be indicated by the Type subfield included in the Frame Control field of the MAC header. Control frame, Management frame, or Data frame may be defined as the frame type. The Type subfield may indicate any of Control frame, Management frame, or Data frame. For example, the Type subfield may be a 2-bit subfield. When 00 is set in the Type subfield, the frame type may be Management frame. When 01 is set in the Type subfield, the frame type may be Control frame. When 10 is set in the Type subfield, the frame type may be Data frame.

[0054] The management frame may be a frame for managing the connection status between devices, the control frame may be a frame for managing the communication status between devices, and the data frame may be a frame containing actual transmission data.

[0055] The frame subtype may be indicated by the Subtype subfield included in the Frame Control field of the MAC header. The following frame subtypes may be defined: Association Request, Association Response, Reassociation Request, Reassociation Response, Probe Request, Probe Response, Beacon, ATIM, Disassociation, Authentication, Deauthentication, Action, Block Ack Request, Block Ack, PS-Poll, RTS, CTS, Ack, CF-End, Data, QoS Data, etc. Subtypes other than those listed above may also be defined.

[0056] The frame subtype may be determined from the Type subfield and Subtype subfield included in the Frame Control field of the MAC header. The Subtype subfield may be a 4-bit subfield. If the Type subfield is set to 00, the Type subfield may indicate a Management frame. If the Type subfield is set to 01, the Type subfield may indicate a Control frame. If the Type subfield is set to 10, the Type subfield may indicate a Data frame.

[0057] For example, if the Type subfield indicates a Management frame and the Subtype subfield is set to 0000, the subtype may be Association Request. If the Type subfield indicates a Management frame and the Subtype subfield is set to 0001, the subtype may be Association Response. If the Type subfield indicates a Management frame and the Subtype subfield is set to 0010, the subtype may be Reassociation Request. If the Type subfield indicates a Management frame and the Subtype subfield is set to 0011, the subtype may be Reassociation Response. If the Type subfield indicates a Management frame and the Subtype subfield is set to 0100, the subtype may be Probe Request. If the Type subfield indicates a Management frame and the Subtype subfield is set to 0101, the subtype may be Probe Response. If the Type subfield indicates a Management frame and the Subtype subfield is set to 1000, the subtype may be Beacon.

[0058] The Beacon frame may be a frame including information such as the Beacon period and SSID. The Beacon frame may be a frame that is periodically transmitted to STAs within a BSS. The Association Response frame may be a frame including information such as a Status code. The Association Response frame may be a frame that is transmitted in response to a received Association Request frame. The Reassociation Response frame may be a frame that includes information such as a Status code. The Reassociation Response frame may be a frame that is transmitted in response to a received Reassociation Request frame. The Probe Response frame may be a frame that includes information such as the Beacon period and SSID. The Probe Response frame may be a frame that is transmitted in response to a received Probe Request frame.

[0059] For example, if the Type subfield indicates a Control frame and the Subtype subfield is set to 1011, the subtype may be RTS. If the Type subfield indicates a Control frame and the Subtype subfield is set to 1100, the subtype may be CTS. If the Type subfield indicates a Control frame and the Subtype subfield is set to 1101, the subtype may be Ack.

[0060] For example, if the Type subfield indicates a Data frame and the Subtype subfield is set to 0000, the subtype may be Data. If the Type subfield indicates a Data frame and the Subtype subfield is set to 1000, the subtype may be QoS Data.

[0061] The Frame body field of a MAC frame format may consist of fields and elements defined for each management frame subtype. Fields and elements may appear in a specified relative order, and non-existent fields or elements may be skipped. An STA that encounters an unrecognized element ID in the frame body of a received management frame ignores that element and continues parsing the remainder of the management frame body (if any) for additional elements with recognizable element IDs. That is, the Frame body of a management frame may contain one or more elements.

[0062] The element format of each element included in the Frame body may be defined by an Element ID field, a Length field, an Element ID Extension field, an information field, etc. The Information field may include information specific to the element. For example, an Element ID of 61 may indicate an element for HT Operation. For example, an Element ID of 191 may indicate an element for VHT Capabilities. For example, an Element ID of 192 may indicate an element for VHT Operation. For example, an Element ID of 255 may indicate an element for HE Capabilities. For example, an Element ID of 255 may indicate an element for HE Operation.

[0063] The Operation element may be information for controlling the operation of a STA within a BSS. The Operation element may be composed of multiple fields.

[0064] The HT Operation element may be defined by an Element ID field, a Length field, a Primary Channel field, an HT Operation information field, and a Basic HT-MCS Set field. The Primary Channel field may indicate the channel number of the primary channel. As described above, the channel location may be indicated by the channel number. The HT Operation information field may consist of a Secondary Channel Offset field, an STA Channel Width field, etc. The Secondary Channel Offset field may indicate the offset of the secondary channel relative to the primary channel. If the Secondary Channel Offset field is set to 1, the secondary channel may be located above the primary channel. If the Secondary Channel Offset field is set to 3, the secondary channel may be located below the primary channel. If the Secondary Channel Offset field is set to 0, the secondary channel may not exist. The STA Channel Width field may define the channel width that the STA can use for transmission. The STA Channel Width field may be set to 0 for 20 MHz. The STA Channel Width field may be set to 1 to allow the use of any channel within the supported channel width set. The operation of the HT STA(s) within the BSS may be controlled by the HT Operation element, i.e., the HT Operation element may be an operation element that controls the operation of the HT STA(s) within the BSS.

[0065] The HT operation element may be transmitted in a Management frame. The HT operation element may be transmitted in a Control frame. The HT operation element may be transmitted in a Data frame. For example, the HT operation element may be transmitted in a Beacon frame. For example, the HT operation element may be transmitted in an Association Response frame. For example, the HT operation element may be transmitted in a Reassociation Response frame. For example, the HT operation element may be transmitted in a Probe Response frame.

[0066] The VHT Operation element may be defined by an Element ID field, a Length field, a VHT Operation information field, and a Basic VHT-MCS And NSS Set field. The VHT Operation information field may consist of a Channel Width field, a Channel Center Frequency Segment 0 field, and a Channel Center Frequency Segment 1 field. The operation of VHT STA(s) within a BSS may be controlled by the HT Operation element and the VHT Operation element. In other words, the VHT Operation element may be an operation element that controls the operation of VHT STAs within a BSS.

[0067] The VHT operation element may be transmitted in a Management frame. The VHT operation element may be transmitted in a Control frame. The VHT operation element may be transmitted in a Data frame. For example, the VHT operation element may be transmitted in a Beacon frame. For example, the VHT operation element may be transmitted in an Association Response frame. For example, the VHT operation element may be transmitted in a Reassociation Response frame. For example, the VHT operation element may be transmitted in a Probe Response frame.

[0068] The Channel Width field in the VHT Operation information field, together with the STA channel width field of the HT operation element, may define the BSS bandwidth. The Channel Width field may be set to 0 for 20 MHz or 40 MHz BSS bandwidth. The Channel Width field may be set to 1 for 80 MHz, 160 MHz, or 80+80 MHz BSS bandwidth. The Channel Width field may be set to 2 for 160 MHz BSS bandwidth. The Channel Width field may be set to 3 for 80+80 MHz BSS bandwidth. Values ​​in the Channel Width field range from 4 to 255 may be reserved.

[0069] The Channel Center Frequency Segment 0 field in the VHT Operation Information field may define the channel center frequency for a VHT BSS of 20 MHz, 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz. For a BSS bandwidth of 20 MHz, 40 MHz, or 80 MHz, the Channel Center Frequency Segment 0 field may indicate the channel center frequency index of the 20 MHz, 40 MHz, or 80 MHz channel on which the VHT BSS operates. For a BSS bandwidth of 160 MHz and the Channel Width subfield is 1, the Channel Center Frequency Segment 0 field may indicate the channel center frequency index of the 80 MHz channel segment containing the primary channel. For a BSS bandwidth of 160 MHz and the Channel Width subfield is 2, the Channel Center Frequency Segment 0 field may indicate the channel center frequency index of the 160 MHz channel on which the VHT BSS operates. The Channel Center Frequency Segment 0 field may indicate the channel center frequency index of the primary 80 MHz channel of the VHT BSS when the BSS bandwidth is 80 + 80 MHz and the Channel Width subfield is 1 or 3.

[0070] The Channel Center Frequency Segment 1 field in the VHT Operation information field may define the channel center frequency for a 160 MHz or 80+80 MHz VHT BSS. The Channel Center Frequency Segment 1 field may be set to 0 for a BSS bandwidth of 20 MHz, 40 MHz, or 80 MHz. The Channel Center Frequency Segment 1 field may indicate the channel center frequency index of the 160 MHz channel on which the VHT BSS operates when the BSS bandwidth is 160 MHz and the Channel Width subfield is 1. The Channel Center Frequency Segment 1 field may be set to 0 when the BSS bandwidth is 160 MHz and the Channel Width subfield is 2. The Channel Center Frequency Segment 1 field may indicate the channel center frequency index of the secondary 80 MHz channel of the VHT BSS when the BSS bandwidth is 80+80 MHz and the Channel Width subfield is 1 or 3.

[0071] The HE Operation element format may consist of an Element ID field, a Length field, an Element ID Extension field, an HE Operation Parameter field, a BSS Color Information field, a Basic HE-MCS And NSS Set field, a VHT Operation Information field, a Max Co-Hosted BSSID Indicator field, a 6 GHz Operation Information field, etc. When operating in the 2.4 GHz band, HE STAs in an HE BSS may be controlled by the HT Operation element and the HE Operation element. When operating in the 5 GHz band, HE STAs in an HE BSS may be controlled by the HT Operation element, the VHT Operation element (if present), and the HE Operation element. When operating in the 6 GHz band, HE STAs in an HE BSS may be controlled by the HE Operation element. In other words, the HE Operation element may be an operation element that controls the operation of HE STAs in a BSS.

[0072] The HE operation element may be transmitted in a Management frame. The HE operation element may be transmitted in a Control frame. The HE operation element may be transmitted in a Data frame. For example, the HE operation element may be transmitted in a Beacon frame. For example, the HE operation element may be transmitted in an Association Response frame. For example, the HE operation element may be transmitted in a Reassociation Response frame. For example, the HE operation element may be transmitted in a Probe Response frame.

[0073] The HE Operation Parameter field format of the HE Operation element format may be composed of a Default PE Duration subfield, a TWT Required subfield, a TXOP Duration RTS Threshold subfield, a VHT Operation Information Present subfield, a Co-Hosted BSS subfield, an ER SU Disabled subfield, a 6 GHz Operation Information Present subfield, a Reserved subfield, etc. The VHT Operation Information Present subfield may be set to 1 to indicate that the VHT Operation Information field is present in the HE Operation element, and may be set to 0 otherwise. The 6 GHz Operation Information Present field may be set to 1 to indicate that the 6 GHz Operation Information field is present, and may be set to 0 otherwise.

[0074] The BSS Color Information field format of the HE Operation element format may be configured with a BSS Color subfield, a Partial BSS Color subfield, a BSS Color Disabled subfield, and the like.

[0075] The 6GHz Operation Information field in the HE Operation element format may provide channel and bandwidth information related to 6GHz operation. The 6GHz Operation Information field format may consist of a Primary Channel field, a Control field, a Channel Center Frequency Segment 0 field, a Channel Center Frequency Segment 1 field, a Minimum Rate field, etc. The Primary Channel field may indicate the channel number of the primary channel in 6GHz. The Channel Center Frequency Segment 0 field may indicate the channel center frequency index of a 20MHz, 40MHz, 80MHz, 160MHz, or 80+80MHz channel of a BSS operating in 6GHz. The Channel Center Frequency Segment 0 field may indicate the channel center frequency index of a primary 80MHz channel when the BSS channel width is 160MHz or 80+80MHz. The Channel Center Frequency Segment 1 field may indicate the channel center frequency index of a 160MHz channel of a BSS operating in 6GHz. The Channel Center Frequency Segment 1 field may indicate the channel center frequency index of the secondary 80 MHz channel when the channel width is 80+80 MHz. The Control field format within the 6 GHz Operation Information field format may be composed of a Channel Width field, a Duplicate Beacon subfield, a Regulatory Info subfield, a Reserved subfield, etc.The Channel Width field indicates the BSS channel width and may be set to 0 for 20 MHz, 1 for 40 MHz, 2 for 80 MHz, or 3 for 80+80 MHz or 160 MHz.

[0076] The EHT Operation element format may be an Operation element for controlling EHT STAs operating in an EHT BSS. When operating in the 2.4 GHz band, EHT STAs in an EHT BSS may be controlled by the HT Operation element, the HE Operation element, and the EHT Operation element. When operating in the 5 GHz band, EHT STAs in an EHT BSS may be controlled by the HT Operation element, the VHT Operation element (if present), the HE Operation element, and the EHT Operation element. When operating in the 6 GHz band, EHT STAs in an EHT BSS may be controlled by the HE Operation element and the EHT Operation element.

[0077] The EHT Operation element format may consist of an Element ID, Length, Element ID Extension, EHT Operation Parameter, Basic EHT-MCS And NSS Set, and EHT Operation Information field. The EHT Operation Information field may consist of a Control subfield, a CCFS0 subfield, a CCFS1 subfield, and a Disabled Subchannel Bitmap subfield. The Control subfield may include a Channel Width subfield. The Channel Width subfield may be a subfield for defining the EHT BSS bandwidth. The Channel Width subfield may define 0 for a 20 MHz EHT BSS bandwidth. The Channel Width subfield may define 1 for a 40 MHz EHT BSS bandwidth. The Channel Width subfield may define 2 for an 80 MHz EHT BSS bandwidth. The Channel Width subfield may define 3 for a 160 MHz EHT BSS bandwidth. The Channel Width subfield may define 4 for a 320 MHz EHT BSS bandwidth. The CCFS0 subfield may define the center frequency of the primary 80 MHz channel of a 20 MHz EHT BSS, a 40 MHz EHT BSS, an 80 MHz EHT BSS, a 160 MHz EHT BSS, or a 160 MHz channel of a 320 MHz EHT BSS. The CCFS0 subfield may indicate the channel center frequency index of the 20 MHz channel, 40 MHz channel, or 80 MHz channel on which the EHT BSS operates for the 20 MHz BSS bandwidth, 40 MHz BSS bandwidth, or 80 MHz BSS bandwidth.The CCFS0 subfield may indicate the channel center frequency index of the primary 80 MHz channel for a 160 MHz BSS bandwidth. The CCFS0 subfield may indicate the channel center frequency index of the primary 160 MHz channel for a 320 MHz BSS bandwidth. The CCFS1 subfield may define the center frequency of the 160 MHz EHT BSS or the 320 MHz EHT BSS. The CCFS1 subfield may be set to 0 for a 20 MHz BSS bandwidth, a 40 MHz BSS bandwidth, or an 80 MHz BSS bandwidth. The CCFS1 subfield may indicate the center frequency index of the 160 MHz channel for a 160 MHz BSS bandwidth. The CCFS1 subfield may indicate the center frequency index of the 320 MHz channel for a 320 MHz BSS bandwidth.

[0078] An Aggregate MSDU (A-MSDU) may be a sequence of A-MSDU subframes. Each A-MSDU subframe may consist of an A-MSDU subframe header followed by an MSDU and 0 to 3 padding. In an A-MSDU subframe, the A-MSDU subframe header may contain the DA, SA, and Length fields. The DA and SA fields may contain the values ​​passed in the MA-UNITDATA.request and MAUNITDATA.indication primitives. The Length field may contain the length of the MSDU in octets (i.e., 8-bit units).

[0079] Fig. 6 is a diagram showing an example of an A-MSDU according to one aspect of this embodiment. In Fig. 6, the MAC frame format may be composed of a MAC header, a Frame Body, and an FCS. Here, the MAC header may be composed of a Frame Control field, a Duration field, an Address 1 field, an Address 2 field, an Address 3 field, a Sequence Control field, an Address 4 field, and a QoS Control field. The MAC frame format may be an MPDU. The Frame Body may be composed of n A-MSDU subframes. Each A-MSDU may be composed of an A-MSDU subframe header, an MSDU, and Padding. The A-MSDU subframe header may be composed of a DA field, an SA field, and a Length field.

[0080] An Aggregate MPDU (A-MPDU) may consist of a sequence of one or more A-MPDU subframes and a variable amount of EOF adding. Each A-MPDU subframe may consist of an MPDU optionally followed by an MPDU delimiter. Each nonfinal A-MPDU subframe within an A-MPDU may have padding octets added to make the subframe length a multiple of four octets. The EOF Padding field may consist of the EOF Padding subframe field and the EOF Padding Octets field. The A-MPDU pre-EOF padding may refer to the contents of the A-MPDU, excluding the EOF Padding field. The MPDU delimiter may consist of the EOF field, Reserved field, MPDULength field, CRC field, and Delimiter Signature field.

[0081] 7 is a diagram showing an example of an A-MPDU according to one aspect of this embodiment. In FIG. 7, the A-MPDU may be composed of n A-MPDU subframe fields and an EOF Padding field. The n A-MPDU subframe fields may be referred to as A-MPDU pre-EOF padding. Each A-MPDU subframe field may be composed of an MPDU delimiter field, an MPDU field, and a padding field. The MPDU delimiter field may be composed of an EOF field, a Reserved field, an MPDU Length field, a CRC field, and a Delimiter Signature field. The EOF Padding field may be composed of an EOF Padding subframe field and an EOF Padding Octets field.

[0082] The process of dividing an MSDU or MMPDU (MAC Management Protocol Data Unit) into smaller MAC-level frames, MPDUs, may be referred to as fragmentation. The MAC may fragment and reassemble MSDUs or MMPDUs carried in individually addressed MPDUs.

[0083] 8 is a diagram showing an example of fragmentation according to one aspect of this embodiment. In FIG. 8, an MSDU may be fragmented into n pieces. The MSDU may be divided into n Frame Bodies, and a MAC HDR (header) and a CRC (Cyclic Redundancy Check) may be added to each Frame Body.

[0084] The PPDU may be composed of a PHY preamble, a PHY header, a PSDU (PHY Service Data Unit), etc. The PPDU may be provided with L-STF, L-LTF, and L-SIG. The PPDU may be provided with HT-STF, HT-LTF, and HT-SIG. The PPDU may be provided with VHT-STF, VHT-LTF, VHT-SIG-A, and VHT-SIG-B. The PPDU may be provided with HE-STF, HE-LTF, HE-SIG-A, and HE-SIG-B. The PPDU may be provided with HT-STF, HT-LTF, and HT-SIG in addition to L-STF, L-LTF, and L-SIG. The PPDU may be provided with VHT-STF, VHT-LTF, VHT-SIG-A, and VHT-SIG-B in addition to L-STF, L-LTF, and L-SIG. In addition to L-STF, L-LTF, and L-SIG, HE-STF, HE-LTF, HE-SIG-A, and HE-SIG-B may be added to the PPDU.

[0085] Fig. 9 is a diagram showing an example of a PPDU according to one aspect of the present embodiment. In Fig. 9, an L-STF and an L-LTF may be added to the PPDU in the PHY layer. In Fig. 9, the PPDU may be composed of a PSDU, a PHY preamble, a PHY header, a tail, and padding. Here, the PSDU may be an A-MPDU in the MAC sublayer. The A-MPDU may be composed of multiple MAC frame formats. Here, one MAC frame format may be composed of a MAC header field, an A-MSDU field, and an FCS field.

[0086] The time interval between frames may be referred to as an IFS (Inter Frame Space). The STA may determine whether the medium is idle by using a carrier sense function at a specified time interval. That is, the STA may perform carrier sense for the IFS period to determine whether the medium is idle.

[0087] A plurality of types of IFS may be defined. For example, the following may be defined as IFS: Reduced Inter Frame Space (RIFS), Short Inter Frame Space (SIFS), Priority Inter Frame Space (PIFS), DCF Inter Frame Space (DIFS), Arbitration Inter Frame Space (AIFS), Extended Inter Frame Space (EIFS), Short Beamforming Inter Frame Space (SBIFS), Beam Refinement Inter Frame Space (BRPIFS), Medium Beamforming Inter Frame Space (MBIFS), and Long Beamforming Inter Frame Space (LBIFS).

[0088] The time interval may differ depending on the type of IFS. For example, a PIFS may be an IFS with a longer time interval than a SIFS. A DIFS may be an IFS with a longer time interval than a PIFS. A priority level for accessing the wireless medium may be provided depending on the type of IFS. In other words, an IFS with a shorter time interval may be an IFS with a higher priority level for accessing the wireless medium.

[0089] SIFS (Short Inter Frame Space) may be the time from the end of the last symbol or signal extension (if present) of the previous frame to the first symbol of the preamble of the next frame seen on the wireless medium.

[0090] Priority Inter Frame Space (PIFS) may be used to control access to the medium to obtain priority access. PIFS may also be used to perform CCA on the secondary 20 MHz channel, secondary 40 MHz channel, and secondary 80 MHz channel before transmission on 40 MHz, 80 MHz, and 160 MHz channels.

[0091] The DCF Inter Frame Space (DIFS) may be used by STAs operating using DCF to transmit data frames (MPDUs) and management frames (MMPDUs). After successfully receiving a frame, a STA using DCF may transmit if the carrier sense (CS) mechanism determines that the medium is idle on a TxDIFS slot boundary and the STA's backoff counter is zero.

[0092] The Arbitration Inter Frame Space (AIFS) may be used for QoS STAs that use EDCAF to access the medium.

[0093] The EIFS (Extended Inter Frame Space) may be used in DCF when the medium is immediately determined to be idle after receiving a frame with an incorrect FCS value.

[0094] The basic access method of the MAC used by the STA may be a Distributed Coordination Function (DFC). DCF may be a class of coordination function in which the same coordination function logic is always active in each STA within a BSS when the network is operating. DCF may be a type of CSMA / CA. DCF may be a function that must be implemented in all STAs.

[0095] To transmit, a STA senses the medium to determine if another STA is transmitting. If the medium is not busy, the STA may transmit. If the medium is determined to be busy, the STA postpones until the current transmission is completed.

[0096] In the CSMA / CA distributed algorithm, there is a gap of a specified duration between frame exchange sequences. The gap of a specified duration between frame exchange sequences may be referred to as an IFS. A transmitting STA ensures that the medium is idle for a required period of time before attempting to transmit. The required period may be a gap of a specified duration between frame exchange sequences. The required period of time may be referred to as an IFS.

[0097] A STA may initialize its backoff counter to a random backoff counter before attempting to transmit again after a deferral or immediately after a successful transmission. The STA may decrement its backoff counter once every aSlotTime while the medium is idle. aSlotTime may be the length of a slot, which may be the slot time used by the MAC to define the IFS. Alternatively, aSlotTime may be a predetermined length of time (e.g., a fixed length in microseconds).

[0098] The basic medium access protocol may be DCF. DCF allows automatic sharing of the medium between compatible PHYs through the use of CSMA / CA and a random backoff counter after the medium is busy. All individually addressed traffic uses immediate positive acknowledgment (Ack frame), and if an Ack frame is not received, a retransmission is scheduled by the sender. Multiple STAs may be waiting for the medium to become available, and collisions are most likely when the medium goes from busy to idle. This necessitates a random backoff procedure to resolve medium contention. STA transmissions may interfere (collision) with other STA transmissions even if the carrier sense function (CS function) indicates the medium is not busy. Interference may be identified when an expected response frame is not received.

[0099] A STA that wants to start transmitting data or management frames using DCF may use the carrier sense mechanism to determine the busy / idle state of the medium. If the medium is busy, the STA waits without interruption for an IFS until the medium is determined to be idle. Here, the type of IFS may be EIFS if the last transition to idle was due to the detection of a frame that was not correctly received on the medium. Otherwise, the type of IFS may be DIFS. After the medium is idle in a DIFS or EIFS, the STA may generate a random backoff count for additional deferral time before transmitting. However, if the backoff counter already contains a non-zero value, random selection may not be performed. The backoff counter may be a pseudorandom integer drawn from a uniform distribution between [0, CW]. CW may be an integer within the range of aCWmin and aCWmax, which is a PHY characteristic. CW may be greater than or equal to aCWmin and less than or equal to aCWmax. CW may also be referred to as the contention window.

[0100] The contention window parameter may take on an initial value of aCWmin. The contention window takes on a series of successive values ​​with each failed MPDU transmission attempt and increment of any STA's retries until the contention window reaches the value of aCWmax. The contention window maintains the value of aCWmax until the contention window is reset when aCWmax is reached. The contention window may be reset to aCWmin upon successful transmission of a data frame or management frame. The contention window may be reset to aCWmin if the SSRC reaches dot11ShortRetryLimit. The set of contention window values ​​may be in ascending order as integer values, powers of two minus one, starting from the PHY-specific aCWmin value and continuing up to the PHY-specific aCWmax. For example, if aCWmin is 7 and aCWmax is 255, the set of contention windows may include 7, 15, 31, 63, 127, and 255.

[0101] For example, in the case of OFDM PHY characteristics with 20 MHz channel spacing, aSlotTime may be 9 μs, in the case of OFDM PHY characteristics with 20 MHz channel spacing, aCWmin may be 15, and in the case of OFDM PHY characteristics with 20 MHz channel spacing, aCWmax may be 1023.

[0102] The QoS facility may include an additional coordination function called the Hybrid Coordination Function (HCF), which is available only in QoS network configurations. The HCF may be implemented in all QoS STAs. The HCF is a coordination function that combines aspects of contention-based and contention-free access methods to provide prioritized, parameterized QoS access to the wireless medium for QoS STAs while continuing to support non-QoS STAs for best-effort transmission. The HCF may include functionality provided by both Enhanced Distributed Channel Access (EDCA) and HCF controlled channel access (HCCA). The HCF may use a contention-based channel access method called the EDCA mechanism for contention-based transmission. The HCF may use a controlled channel access method called the HCCA mechanism for contention-free transmission.

[0103] HCF Controlled Channel Access (HCCA) may be a channel access mechanism used by a Hybrid Coordinator (HC) to coordinate contention-free medium usage by QoS STAs for individually addressed downlink, uplink, and direct link transmissions.

[0104] The EDCA mechanism may provide STAs with differentiated and distributed access to the wireless medium using eight different User Priorities (UPs). UPs may be values ​​associated with MAC Service Data Units (MSDUs) and indicate how to process the MSDUs. UPs may be assigned to MSDUs by MAC-over-layers. UPs may take values ​​from 0 to 7. The EDCA mechanism may define four Access Categories (ACs) to support the delivery of traffic using STA UPs. An AC may be a label for a common set of EDCA parameters used by QoS STAs to contend for the channel and transmit MSDUs with a specific priority. An AC may take one of the values ​​AC_BE, AC_BK, AC_VI, or AC_VO. AC_BE, AC_BK, AC_VI, and AC_VO may indicate access categories corresponding to best effort, background, video, and voice, respectively.

[0105] A Quality of Service (QoS) facility may be an extension, channel access rule, frame format, frame exchange sequence, or managed object used to provide parameterized and prioritized QoS. A QoS STA may be an STA that implements the QoS facility. A QoS AP may be an AP that supports the QoS facility. A QoS BSS may be a BSS that provides the QoS facility. An Infrastructure QoS BSS may include a QoS AP.

[0106] The Enhanced Distributed Channel Access Function (EDCAF) may be a logical function within a QoS STA that uses EDCA to determine when frames in a transmit queue with an associated AC are allowed to transmit over the wireless medium. There may be one EDCAF per AC. DCFs and HCFs may be defined to operate within the same BSS.

[0107] Each EDCAF may maintain a backoff counter measured in backoff slots. When the backoff procedure is invoked, the backoff counter may be set to an integer value randomly selected with a uniform distribution between 0 and CW. AIFS may be defined as AIFSN × aSlotTime + aSIFSTime. For example, for 20 MHz channel spacing in OFDM PHY characteristics, aSlotTime may be 9 μs and aSIFSTime may be 16 μs. AIFSN may be different for each AC. For example, if the AC is AC_BK, AIFSN may be 7. If the AC is AC_BE, AIFSN may be 3. If the AC is AC_VI, AIFSN may be 2. If the AC is AC_VO, AIFSN may be 2. CW may be ascending as integer values ​​calculated by multiplying the number by 1 by a power of 2, starting from a PHY-specific CWmin value and continuing to a PHY-specific CWmax. CWmin and CWmax may be different for each AC. For example, if AC is AC_BK, CWmin may be aCWmin and CWmax may be aCWmax. If AC is AC_BE, CWmin may be aCWmin and CWmax may be aCWmax. If AC is AC_VI, CWmin may be {(aCWmin + 1) / 2} - 1 and CWmax may be aCWmin. If AC is AC_VO, CWmin may be {(aCWmin + 1) / 4} - 1 and CWmax may be {(aCWmin + 1) / 2} - 1. For OFDM PHY characteristics with 20 MHz channel spacing, aCWmin may be 15. For OFDM PHY characteristics with 20 MHz channel spacing, aCWmax may be 1023. A STA may decrement its backoff counter once every aSlotTime period while the medium is idle. The counter takes the next value in the series each time an MPDU transmission attempt fails and any STA's retries increase.

[0108] In HCF, the basic unit of allocation of transmission rights to the wireless medium may be a TXOP. A TXOP (Transmission Opportunity) may be a time interval during which a specific QoS STA has the right to initiate a frame exchange sequence on the wireless medium. A TXOP may be defined by a start time and a maximum duration. A TXOP may be acquired by EDCA. That is, a STA may acquire a TXOP if it performs EDCA.

[0109] FIG. 10 is a diagram illustrating an example of a backoff procedure according to one aspect of the present embodiment. In FIG. 10, the horizontal axis may represent time. 1001 may represent a transmission from STA#1. 1002 may represent an IFS. 1003 may represent a backoff counter. 1003 may be referred to as a contention window. 1004 may represent a transmission from STA#2. In FIG. 10, STA#2 may detect 1001 on the channel. While detecting 1001, STA#2 may determine that the channel is busy. In other words, 1001 may represent a period during which the channel is determined to be busy. STA#2 may perform carrier sensing to determine whether the channel is busy. After the period 1001 ends and STA#2 determines that the channel is idle, it may perform carrier sensing during the period 1002. For example, 1002 may represent a DIFS. 1002 may represent an AIFS. If STA#2 is idle during the period 1002, it may start 1003. 1003 decrements the backoff counter while the channel is idle. For example, six backoff counters may be generated in 1003. While the channel is idle, the backoff counter is decremented, and when the backoff counter reaches 0, STA#2 may transmit (1004). Here, the backoff counter may be determined between 0 and CW. CW may be a value selected from a range of values ​​between aCWmin and aCWmax. The channel may be referred to as a wireless medium.

[0110] The carrier sensing mechanism may be a mechanism that determines whether the medium is busy or idle by combining the Network Allocation Vector (NAV) status and the physical carrier sense of the STA transmitter. The NAV is maintained by each STA and may be an indicator of the period during which the STA does not initiate transmission on the wireless medium, regardless of whether the STA's Clear Channel Assessment (CCA) function senses the medium is busy.

[0111] The carrier sensing mechanism in the STA may be performed in the physical layer processing unit SU3 and / or the MAC layer processing unit SU3, and the carrier sensing mechanism in the AP may be performed in the physical layer processing unit AU3 and / or the MAC layer processing unit AU3.

[0112] The NAV may be a counter that counts down to zero at a constant rate. The STA may indicate that the virtual carrier sense is idle if the NAV counter is zero. The STA may indicate that the virtual carrier sense is busy if the NAV counter is not zero. The physical carrier sense function and the virtual carrier sense function may be used to determine the state of the medium. If either the physical carrier sense function or the virtual carrier sense function indicates busy, the medium may be considered busy. If both the physical carrier sense function and the virtual carrier sense function indicate idle, the medium may be considered idle. The virtual carrier sense may be referred to as the NAV. The NAV may be provided by all MACs. The NAV counter may be referred to as the NAV timer.

[0113] The physical carrier sense function in the STA may be controlled by the physical layer processing unit SU3. The virtual carrier sense function in the STA may be controlled by the MAC layer processing unit SU4. The physical carrier sense function in the AP may be controlled by the physical layer processing unit AU3. The virtual carrier sense function in the AP may be controlled by the MAC layer processing unit AU4. The NAV in the STA may be controlled by the MAC layer processing unit SU4. The NAV in the AP may be controlled by the MAC layer processing unit AU4.

[0114] A STA may set its NAV if the address field of a received frame is not its own address. If a STA receives at least one valid frame in a PSDU, it may update its NAV using the information in any valid Duration field in the PSDU. If the value indicated in the Duration field of a received frame is greater than the current NAV value, the STA may update its NAV. If the RA (address) of a received frame is equal to the STA's own MAC address, the STA does not update its NAV.

[0115] Carrier sensing (CS) may be performed through both physical and virtual mechanisms. Carrier sensing may also be referred to as a carrier sense function. Carrier sensing may also be referred to as a carrier sense mechanism. The virtual carrier sense mechanism distributes reservation information that notifies advance notice of medium usage. Exchanging RTS and CTS frames before the actual data frames may be one means of distributing medium reservation information. RTS and CTS frames may include a Duration field that defines the period during which the medium is reserved for transmitting the actual data and Ack frames. STAs that receive an RTS frame (sent by the originating STA) or a CTS frame (sent by the destination STA) process the medium reservation. STAs can know that the medium will be used to transmit data frames even if they cannot receive from the originating STA. Medium reservation information may be distributed in the Duration / ID field of individually addressed frames. The Duration / ID field may indicate the time (duration) for which the medium is reserved. The Duration / ID field may indicate the period of time for which the medium is reserved, which ends with the immediately following Ack frame. In the case of a fragment sequence, the Duration / ID field may indicate the time the medium is reserved until the end of the Ack frame following the next fragment. The RTS / CTS mechanism may also work in the case of overlapping BSSs using the same channel. The medium reservation mechanism may also work across BSS boundaries.

[0116] The RTS (Request To Send) frame format may include a Frame Control field, a Duration field, an RA field, a TA field, and an FCS field. The Duration field of the RTS frame format may indicate the time (in microseconds) required to transmit the pending data or management frame, one CTS frame, one Ack frame, and three SIFS. The RA field of the RTS frame may be the address of the STA that is the intended direct recipient of the pending individually addressed frame. The TA field may be the address of the STA sending the RTS frame or the bandwidth signal TA of the STA sending the RTS frame.

[0117] The CTS (Clear To Send) frame format may include a Frame Control field, a Duration field, an RA field, and an FCS field. The Duration field of a CTS frame format transmitted in response to an RTS frame may be the Duration field of the immediately preceding RTS frame minus the time required to transmit the CTS frame and its corresponding SIFS. That is, it may be the time required to transmit the pending data or management frame, one Ack frame, and two SIFS. If the CTS frame is the first frame of an exchange and the pending data or management frame requires acknowledgment, the Duration field may be the time (in microseconds) required to transmit the pending data or management frame, two SIFS, and one Ack frame. If the CTS frame is the first frame of an exchange and the pending data or management frame does not require immediate acknowledgment, the Duration field may be the time required to transmit the pending data or management frame and one SIFS. If the CTS frame is a response to an RTS frame, the RA field of the CTS frame may be set to the address in the TA field of the RTS frame and the Individual / Group bit may be set to 0. If the CTS frame is the first frame in a frame exchange, the RA field may be set to the sender's MAC address.

[0118] FIG. 11 is a diagram illustrating an example of a NAV according to one aspect of the present embodiment. In FIG. 11, the horizontal axis may represent time. For example, 1101 may be a timeline of AP#1's operation. 1102 may be a timeline of STA#1's operation. 1103 may be a timeline of AP#2's operation. 1104 may be a timeline of STA#2's operation. 1101, 1102, 1103, and 1104 may be timelines on the same channel. 1105 may be an RTS frame. 1106 may be the NAV period of AP#1. 1107 may be a CTS frame. 1108 may be the NAV period of STA#2. 1109 may be a Data frame. 1110 may be an AcK frame. 1111 may be an IFS. 1112 may be a contention window (backoff counter, backoff procedure). STA#1 may send 1105 to AP#2. Upon receiving 1105, AP#1 may set 1106 for the period indicated in the Duration field of the RTS. Upon receiving 1105, AP#2 may send 1107 to STA#1. Upon receiving 1107, STA#2 may set 1108 for the period indicated in the Duration field of the CTS. Upon receiving 1107, STA#1 may send 1109. Upon receiving 1109, AP#2 may send 1110 to STA#1. Upon completing 1106, AP#1 may start 1112 at 1111 if the channel is idle. Upon completing 1108, STA#2 may start 1112 at 1111 if the channel is idle. The period between 1105 and 1107 may be an IFS. AP#2 may transmit 1107 if the channel is idle during the IFS period before transmitting 1107. An IFS may be transmitted between 1107 and 1109. STA#1 may transmit 1109 if the channel is idle during the IFS period before transmitting 1109. An IFS may be transmitted between 1109 and 1110. AP#2 may transmit 1110 if the channel is idle during the IFS period before transmitting 1110.Here, for example, AP#1 may be 202 in Fig. 2. For example, STA#1 may be 207 in Fig. 2. For example, AP#2 may be 206 in Fig. 2. For example, STA#2 may be 2088 in Fig. 2. 1101 may be a timeline of the operation of the AP or STA. 1102 may be a timeline of the operation of the AP or STA. 1103 may be a timeline of the operation of the AP or STA. 1104 may be a timeline of the operation of the AP or STA.

[0119] Channel bonding may involve transmission using one or more 20 MHz channels. Alternatively, channel bonding may involve transmission using multiple 20 MHz channels. Channel bonding may involve transmission using multiple adjacent 20 MHz channels. Channel bonding may also be referred to as channel aggregation. Channel bonding transmits data using multiple channels simultaneously, resulting in a wider bandwidth and improved data transmission speed. The multiple channels used by members of a BSS may include a primary channel and one or more secondary channels, and channel bonding may be performed using multiple of these channels.

[0120] The primary channel may be a channel common to all STAs that are members of a BSS. The primary 20 MHz channel may be a 20 MHz channel on which a 20 MHz PPDU is transmitted in a 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz BSS. The primary 40 channel may be a 40 MHz channel on which a 40 MHz PPDU is transmitted in an 80 MHz, 160 MHz, or 80+80 MHz BSS. The primary 80 channel may be an 80 MHz channel on which an 80 MHz PPDU is transmitted in a 160 MHz or 80+80 MHz BSS. The primary 160 MHz channel may be a 160 MHz channel that includes the primary 20 MHz channel in a 320 MHz BSS. For example, the primary channel in a 20 MHz, 40 MHz, 80 MHz, 160 MHz, 80+80 MHz, or 320 MHz BSS may be referred to as the primary 20 MHz channel. The primary channel may be the channel on which the backoff procedure is performed.

[0121] A secondary channel is a channel associated with a primary channel and may be used to create a wider channel than the primary channel. For example, a secondary channel in a 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz BSS may be referred to as a secondary 20 MHz channel. A secondary 20 MHz channel may be a 20 MHz channel adjacent to a primary 20 MHz channel in a 40 MHz BSS. A secondary 20 MHz channel may be a channel that combines with a primary 20 MHz channel to form a 40 MHz channel in a 40 MHz BSS. A secondary 20 MHz channel may be a 20 MHz channel adjacent to a primary 20 MHz channel in an 80 MHz BSS. A secondary 20 MHz channel may be a channel that combines with a primary 20 MHz channel to form a primary 40 MHz channel in an 80 MHz BSS. A secondary 20 MHz channel may be a 20 MHz channel adjacent to a primary 20 MHz channel in a 160 MHz or 80+80 MHz BSS. A secondary 20 MHz channel may be a channel that combines with a primary 20 MHz channel to form a primary 40 MHz channel in a 160 MHz or 80+80 MHz BSS. A secondary 40 MHz channel may be a 40 MHz channel adjacent to a primary 40 MHz channel to form an 80 MHz channel in an 80 MHz BSS. A secondary 40 MHz channel may be a 40 MHz channel adjacent to a primary 40 MHz channel to form a primary 80 MHz channel in a 160 MHz or 80+80 MHz BSS.A secondary 80MHz channel may be an 80MHz channel that does not include a primary 20MHz channel in a 160MHz or 80+80MHz BSS. A secondary 80MHz channel may be combined with a primary 80MHz channel to form a 160MHz or 80+80MHz channel. A secondary 160MHz channel may be a 160MHz channel that does not include a primary 20MHz channel in a 320MHz BSS, combining with a primary 160MHz channel to form a 320MHz channel for a 320MHz EHT BSS.

[0122] A non-primary channel may be any 20 MHz channel other than the primary 20 MHz channel in a 40 MHz channel, 80 MHz channel, 160 MHz channel, 80+80 MHz channel, or 320 MHz channel.

[0123] FIG. 12 is a diagram showing an example of channel bonding according to one aspect of this embodiment. In FIG. 12, 1201, 1202, 1203, 1204, 1205, 1206, 1207, and 1208 may each be a 20 MHz channel. The horizontal axis of FIG. 12 may represent frequency. FIG. 12 may also show a channel configuration for a BSS operating with a 160 MHz channel width. 1201 may be a primary 20 MHz channel. 1201 may be referred to as a primary channel. 1202 may be a secondary 20 MHz channel. 1203 and 1204 may form a secondary 40 MHz channel. 1205, 1206, 1207, and 1208 may form a secondary 80 MHz channel. 1202, 1203, 1204, 1205, 1206, 1207, and 1208 may be referred to as secondary channels.

[0124] The Operating class may indicate an index to a set of radio operating values ​​in a regulatory domain. The value of Operating class may indicate a frequency for a channel number, a usable channel center frequency, or a maximum usable channel width. The value of Operating class may indicate a Channel starting frequency, Channel Spacing, Channel set, etc. The Channel set may be a list of integer channel numbers that are valid for the regulatory domain and class. The Channel Spacing may be the frequency difference between non-overlapping adjacent channel center frequencies when using the maximum bandwidth of one frequency segment allowed by the Operating class. The Operating class value may be transmitted in a frame. For example, the Operating class value may be transmitted in a Beacon frame. The Operating class value may be transmitted in a Probe Response frame. The Operating class value may be an Operating class index.

[0125] The center frequency of the primary 20 MHz channel may be determined by Channel starting frequency + 5 × dot11CurrentPrimaryChannel. dot11CurrentPrimaryChannel may be the channel number of the primary channel. The STA may determine dot11CurrentPrimaryChannel from an Operation element included in a frame received from an AP. The STA may determine dot11CurrentPrimaryChannel from information in the Primary Channel field included in an HT Operation element. The STA may determine dot11CurrentPrimaryChannel from information in the Primary Channel field included in an HT Operation element. The STA may determine dot11CurrentPrimaryChannel from information in the Primary channel field in the 6 GHz Operation Information field included in an HE Operation element. For example, a STA receiving a Beacon frame from an AP may determine the primary channel from the Primary Channel field of the HT operation element included in the Beacon frame. The Channel starting frequency may be defined as dot11ChannelStartingFactor × 500 kHz. dot11ChannelStartingFactor may be indicated in the Operating Class field.

[0126] The AP may include information related to the primary channel in an operation element and transmit the frame. The information related to the primary channel may be the channel number of the primary channel. The AP may include the channel number of the primary channel in an operation element and transmit the frame. For example, the AP may indicate the channel number of the primary channel in the Primary channel field of the HT operation element. For example, the AP may indicate the channel number of the primary channel in the Primary channel field in the 6 GHz Operation Information field included in the HE operation element.

[0127] In channel bonding, a STA may perform a backoff procedure on the primary channel and sense and transmit on secondary channels for a PIFS. The STA may acquire an EDCA TXOP based on activity on the primary channel. The transmission bandwidth may be determined by the CCA status of non-primary channels during the PIFS before transmission.

[0128] The PHY-CCA.indication primitive may be a primitive indicating the current state of the medium from the PHY to the MAC entity. The PHY-CCA.indication primitive may include a STATE parameter. The PHY-CCA.indication primitive may include a channel-list parameter. The STATE parameter of the PHY-CCA.indication primitive may be one of two values: BUSY (busy) or IDLE (idle). The PHY-CCA.indication primitive may include at least the STATE parameter. The PHY-CCA.indication primitive may include at least the channel-list parameter. The PHY-CCA.indication primitive may include at least the STATE and channel-list parameters. The STATE parameter value of the PHY-CCA.indication primitive may be BUSY if the PHY's evaluation of the channels indicates that the channels are unavailable. Otherwise, the STATE parameter value of the PHY-CCA.indication primitive may be IDLE. If the STA is in the IDLE state, the channel-list parameter is not present. If the CCA is determined by a single channel due to the type of PHY being operated on, the channel-list parameter is not present. Otherwise, the channel-list parameter may contain a set indicating busy channels. That is, if the CCA is determined by multiple channels and is BUSY, the channel-list parameter may be present. For example, entries in the Channel-list parameter may indicate primary, secondary, secondary40, and secondary80.

[0129] For example, if the entry for the channel-list parameter of PHY-CCA.indication primitive is set to "primary," it may indicate that the primary channel is busy. For example, if the entry for the channel-list parameter of PHY-CCA.indication primitive is set to "secondary," it may indicate that the secondary channel (secondary 20MHz channel) is busy. For example, if the entry for the channel-list parameter of PHY-CCA.indication primitive is set to "secondary40," it may indicate that the secondary40 channel is busy. For example, if the entry for the channel-list parameter of PHY-CCA.indication primitive is set to "secondary80," it may indicate that the secondary80 channel is busy.

[0130] The PHY-CCA.indication primitive may be generated when the state of a channel changes from idle to busy, or when the state of a channel changes from busy to idle, or when an entry in the channel-list parameter changes.

[0131] When the MAC receives a PHY-CCA.indication with a channel-list parameter present, it may determine which channels are idle. If the channel-list parameter entry in the PHY-CCA.indication is primary, it may determine that no channels are idle. If the channel-list parameter entry in the PHY-CCA.indication is secondary, it may determine that the primary channel is idle. If the channel-list parameter entry in the PHY-CCA.indication is secondary40, it may determine that the primary channel and the secondary 20 MHz channel are idle. If the channel-list parameter entry in the PHY-CCA.indication is secondary80, it may determine that the primary channel, the secondary 20 MHz channel, and the secondary 40 MHz channel are idle.

[0132] For example, in FIG. 12 , 1201 may be a primary channel. 1202 may be a secondary channel (secondary 20 MHz channel). 1203 and 1204 may form a secondary 40 MHz channel. 1205, 1206, 1207, and 1208 may form a secondary 80 MHz channel. In other words, in FIG. 12 where the bandwidth is 160 MHz, the primary channel may be 1201, the secondary channel (secondary 20 MHz channel) may be 1201, the secondary 40 MHz channel may be 1203 and 1204, and the secondary 80 MHz channel may be 1205, 1206, 1207, and 1208. For example, when the channel state of the primary channel (1201) changes from idle to busy, the STA may issue a primitive (PHY-CCA.indication(BUSY,{primary})) indicating that the primary channel is busy. When the channel state of the primary channel changes from busy to idle, the STA may issue a primitive (PHY-CCA.indication(IDLE,{primary})) indicating that the primary channel is idle. If a primitive (PHY-CCA.indication(BUSY,{primary})) indicating that the primary channel is idle is issued on the primary channel, it may be determined that there is no idle channel. If the primary channel is idle, the STA may issue a primitive related to the secondary channel (1202).If the secondary channel (secondary 20MHz channel) is idle, the STA may issue a primitive (PHY-CCA.indication(IDLE,{secondary})) indicating that the secondary channel is idle. If the secondary channel is busy, the STA may issue a primitive (PHY-CCA.indication(BUSY,{secondary})) indicating that the secondary channel (secondary 20MHz channel) is busy. PHY-CCA.indication(IDLE,{secondary}) may indicate that the primary channel and secondary channel are idle. PHY-CCA.indication(BUSY,{secondary}) may indicate that the primary channel is idle and the secondary channel is busy. If the primary channel and secondary 20MHz channel are idle, the STA may issue a primitive related to the secondary 40MHz channel (composed of 1202 and 1204). If the secondary 40MHz channel is idle, the STA may issue a primitive (PHY-CCA.indication(IDLE,{secondary40})) indicating that the secondary 40MHz channel is idle. If the secondary 40MHz channel is busy, the STA may issue a primitive (PHY-CCA.indication(BUSY,{secondary40})) indicating that the secondary 40MHz channel is busy. PHY-CCA.indication(IDLE,{secondary40}) may indicate that the primary channel, secondary channel, and secondary 40MHz channel are idle.PHY-CCA.indication(IDLE,{secondary40}) may indicate that the primary channel and secondary channel are idle and the secondary 40MHz channel is busy. If the primary channel, secondary 20MHz channel, and secondary 40MHz channel are idle, the STA may issue a primitive related to the secondary 80MHz channel (comprised of 1205-1208). If the secondary 80MHz channel is idle, the STA may issue a primitive (PHY-CCA.indication(IDLE,{secondary80})) indicating that the secondary 80MHz channel is idle. If the secondary 80MHz channel is busy, the STA may issue a primitive (PHY-CCA.indication(BUSY,{secondary80})) indicating that the secondary 80MHz channel is busy. PHY-CCA.indication(IDLE,{secondary 80}) may indicate that the primary channel, secondary channel, secondary 40 MHz channel, and secondary 80 MHz channel are idle. PHY-CCA.indication(IDLE,{secondary 80}) may indicate that the primary channel, secondary channel, and secondary 40 MHz channel are idle and the secondary 80 MHz channel is busy.

[0133] The STA may determine a PHY-CCA.indication primitive in the physical layer processing unit SU3. The STA may indicate the PHY-CCA.indication primitive determined in the physical layer processing unit SU3 to the MAC layer processing unit SU4. The AP may issue a PHY-CCA.indication primitive in the physical layer processing unit AU3. The AP may indicate the PHY-CCA.indication primitive determined in the physical layer processing unit AU3 to the MAC layer processing unit AU4.

[0134] A STA with an operation channel width of W MHz may issue a PHY-CCA.indication(BUSY, {primary}) primitive within a CCATime period if it detects the start of a PPDU occupying at least the primary 20 MHz channel with a probability of at least a predetermined percentage (e.g., 90% or more) and the power of the preamble or PPDU measured in the primary 20 MHz channel is at least a predetermined value (e.g., -82 dBm or more). That is, a STA may issue a PHY-CCA.indication(BUSY, {primary}) primitive when it receives a non-HT duplicate or PPDU exceeding -82 dBm in the primary 20 MHz channel. -82 dBm may be the threshold for determining whether the channel is idle or busy.

[0135] The receiver issues a PHY-CCA.indication(BUSY, {primary}) primitive for any signal that exceeds a threshold (-62 dBm) on the primary 20 MHz channel that is a predetermined value (e.g., 20 dB) higher than the sensitivity of the lowest modulation and coding rate on the primary 20 MHz channel within aCCATime after the signal arrives at the receiver's antenna. Thereafter, while the threshold remains exceeded, the receiver does not issue a PHY-CCA.indication(BUSY, {secondary}), PHY-CCA.indication(BUSY, {secondary40}), PHY-CCA.indication(BUSY, {secondary80}), or PHY-CCA.indication(IDLE) primitive. That is, the receiver may issue a PHY-CCA.indication(BUSY, {primary}) primitive upon receiving any signal above -62 dBm on the primary 20 MHz channel. -62 dBm may be the threshold for determining whether the channel is idle or busy.

[0136] The PHY issues a PHY-CCA.indication(BUSY, {primary}) primitive if there are no conditions for issuing the PHY-CCA.indication(BUSY, {primary}) primitive and any signal in the secondary 20 MHz channel exceeds the threshold of -62 dBm or greater within aCCATime after arriving at the receiver antenna in an idle 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz operating channel width. In this case, the PHY does not issue a PHY-CCA.indication(BUSY,{secondary40}), PHY-CCA.indication(BUSY,{secondary80}), or PHY-CCA.indication(IDLE) primitive. The PHY shall issue a PHY-CCA.indication(BUSY, {primary}) primitive when no conditions exist for issuing the PHY-CCA.indication(BUSY, {primary}) primitive and a 20 MHz preamble or PPDU of -72 dBm or greater is detected on the secondary 20 MHz channel with a probability of 90% or greater within aCCAMidTime in an idle 40 MHz, 80 MHz, 160 MHz, or 80+80 MHz operating channel width. -72 dBm may be the threshold for determining whether a channel is idle or busy.

[0137] If there are no conditions for issuing the PHY-CCA.indication(BUSY, {primary}) or PHY-CCA.indication(BUSY, {secondary}) primitives, and any signal in the secondary 40 MHz channel exceeds the threshold of -59 dBm or greater within aCCATime after arriving at the receiver antenna in an idle 80 MHz, 160 MHz, or 80+80 MHz operating channel width, the PHY shall issue the PHY-CCA.indication(BUSY, {secondary40}) primitive. In this case, the PHY shall not issue the PHY-CCA.indication(BUSY, {secondary80}) primitive or the PHY-CCA.indication(IDLE) primitive. The PHY shall issue the PHY-CCA.indication(BUSY, {primary}) primitive when there are no conditions for issuing the PHY-CCA.indication(BUSY, {secondary}) primitive and the PHY detects a 40 MHz preamble or PPDU of -72 dBm or greater on the secondary 40 MHz channel with a probability of 90% or greater within aCCAMidTime period in an idle 80 MHz, 160 MHz, or 80+80 MHz operating channel width.The PHY shall issue a PHY-CCA.indication(BUSY, {primary}) primitive if no conditions exist for issuing the PHY-CCA.indication(BUSY,{secondary}) primitive and the PHY detects a 20 MHz preamble or PPDU of -72 dBm or greater with a probability of 90% or greater within a CCAMidTime period in any 20 MHz subchannel of a secondary 40 MHz channel in an idle 80 MHz, 160 MHz, or 80+80 MHz operating channel width. -72 dBm may be the threshold for determining whether a channel is idle or busy.

[0138] The PHY shall issue the PHY-CCA.indication(BUSY,{primary}), PHY-CCA.indication(BUSY,{secondary}), or PHY-CCA.Indication(BUSY,{secondary40}) primitive when there are no conditions that would require it and when there is any signal greater than -56 dBm in the secondary80 MHz channel in an idle 160 MHz or 80+80 MHz operating channel width. The PHY shall issue the PHY-CCA.indication(BUSY,{primary}), PHY-CCA.indication(BUSY,{secondary}), or PHY-CCA.Indication(BUSY, {secondary40}) primitive when no conditions exist for issuing the primitive and an 80 MHz preamble or PPDU of -69 dBm or greater is detected in the secondary 80 MHz channel with a probability of 90% or greater within aCCAMidTime in an idle 160 MHz or 80+80 MHz operating channel width. The PHY shall issue a PHY-CCA.indication(BUSY,{primary}), PHY-CCA.indication(BUSY,{secondary}), or PHY-CCA.Indication(BUSY, {secondary40}) primitive when there are no conditions for issuing such primitives and when, in an idle 160 MHz or 80+80 MHz operating channel width, a 40 MHz preamble or PPDU of -72 dBm or greater is detected in any 40 MHz subchannel of the secondary 80 MHz channel with a probability of 90% or greater within aCCAMidTime.The PHY issues a PHY-CCA.indication(BUSY,{primary}), PHY-CCA.indication(BUSY,{secondary}), or PHY-CCA.Indication(BUSY,{secondary40}) primitive when the conditions for issuing the primitive do not exist and, in an idle 160 MHz or 80+80 MHz operating channel width, a 20 MHz preamble or PPDU is detected at or above -72 dBm in any 20 MHz subchannel of the secondary 80 MHz channel with a probability greater than 90% within aCCAMidTime, where -56 dBm, -69 dBm, and -72 dBm may be thresholds for determining whether the channel is idle or busy.

[0139] The threshold may be compared with the signal level of the receiving antenna. In the STA, the signal level compared with the threshold may be the level of the signal received by the antenna unit SU1. In the AP, the signal level compared with the threshold may be the level of the signal received by the antenna unit AU1.

[0140] STAs may perform spatial reuse. Spatial reuse may be the transmission of a PPDU under certain conditions. Spatial reuse may also be the transmission of a PPDU under certain conditions when a PPDU that interferes with transmission is detected. Spatial reuse may be a procedure in which, if a PPDU is received and certain conditions are met, a NAV update is not performed based on the PPDU, and a backoff procedure and transmission is performed. For example, spatial reuse may be performed to identify signals from overlapping BSSs (OBSSs) and manage interference, thereby enabling more frequent medium reuse between OBSSs in dense deployment scenarios. Spatial reuse may have two independent spatial reuse modes: OBSS PD-based spatial reuse and PSR-based spatial reuse. APs participating in spatial reuse may request related non-AP STAs to collect neighbor information by sending a Beacon request. A Beacon request / report pair allows a STA to request a list of APs that can receive Beacons on a specified channel from another STA. Beacon requests / reports may provide a means for requesting STAs to obtain beacons, probe responses, and measurement pilot information received from responding STAs. APs will not set measurement modes in Beacon requests to associated STAs that the STA does not explicitly support via the RM Enabled Capability element. The RM Enabled Capabilities element may advertise the STA's support for radio measurements. APs sending Beacon requests may request that non-AP STAs collect information about BSSs matching a specific BSSID and / or SSID.An AP sending a Beacon request can request that non-AP STAs generate reports only on the channels on which the requesting AP is operating or on channels to which the requesting AP is considering switching. An AP sending a Beacon request can also request that non-AP STAs include the Operation element of neighboring APs to assist in determining the BSS color information of the neighboring APs.

[0141] OBSS PD-based spatial reuse may have two operation types. The first type may allow a STA to ignore inter-BSS PPDUs using the non-SRG OBSS PD level under certain conditions. The second type may allow a STA to ignore inter-BSS PPDUs identified as SRG PPDUs using the SRG OBSS PD level under certain conditions. The non-SRG OBSS PD Min offset may be fixed and defined in the specification. The SRG OBSS PD Min offset may be defined by the AP. A STA may operate using one of the two types, neither type, or both types simultaneously. That is, a STA may operate using only the non-SRG OBSS PD level (first type). A STA may operate using only the SRG OBSS PD level (second type). A STA may operate using both the non-SRG OBSS PD level and the SRG OBSS PD level. A STA may operate without using either the non-SRG OBSS PD level or the SRG OBSS PD level.

[0142] A STA may receive a frame including a Spatial Reuse Parameter Set element. An AP may receive a frame including a Spatial Reuse Parameter Set element. The Spatial Reuse Parameter Set element may provide information required by the STA when performing OBSS PD-based spatial reuse and PSR-based spatial reuse. For example, the Spatial Reuse Parameter Set element may be included in a frame such as a Beacon frame, an Association Response frame, a Reassociation Response frame, or a Probe Response frame. It may also be included in a frame other than the above. The Spatial Reuse Parameter Set element may consist of an Element ID field, a Length field, an Element ID Extension field, an SR control field, a Non-SRG OBSS PD Max Offset field (if present), an SRG OBSS PD Min Offset field (if present), an SRG OBSS PD Max Offset field (if present), an SRG BSS Color Bitmap field (if present), and an SRG Partial BSSID Bitmap field (if present). The Non-SRG OBSS PD Max Offset field may contain an unsigned integer that is added to -82 dBm to generate the value of the Non-SRG OBSS PD Max parameter. The SRG OBSS PD Min Offset field may contain an unsigned integer that is added to -82 dBm to generate the value of the SRG OBSS PD Min parameter. The SRG OBSS PD Max Offset field may contain an unsigned integer that is added to -82 dBm to generate the value of the SRG OBSS PD Max parameter.The SRG BSS Color Bitmap field may be a bitmap indicating the BSS color values ​​used by members of the SRG of which the transmitting STA is a member. The SRG Partial BSSID Bitmap field may be a bitmap indicating the partial BSSID values ​​used by members of the SRG of which the transmitting STA is a member.

[0143] The SR control field may consist of a PSR Disallowed subfield, a Non-SRG OBSS PD SR Disallowed subfield, an SRG Information Present subfield, and a HESIGA_Spatial_reuse_value15_allowed subfield. The PSR Disallowed subfield of the SR control field may indicate whether PSR-based SR transmission is allowed for non-AP STAs associated with the AP that transmitted this element. When the PSR Disallowed subfield is set to 1, PSR-based SR transmission is not allowed. When the PSR Disallowed subfield is set to 0, PSR-based SR transmission is allowed. The Non-SRG OBSS PD SR subfield of the SR control field may indicate whether Non-SRG OBSS PD SR transmission is allowed for non-AP STAs associated with the AP that transmitted this element. When the Non-SRG OBSS PD SR subfield is set to 1, Non-SRG OBSS PD SR transmission is not allowed. When the Non-SRG OBSS PD SR subfield is 0, Non-SRG OBSS PD SR transmission is allowed. The Non-SRG Offset Present subfield of the SR control field may indicate whether the Non-SRG OBSS PD Max Offset field is present in the Spatial Reuse Parameter Set element. When the Non-SRG Offset Present subfield is 1, the Non-SRG OBSS PD Max Offset field is present. When the SRG Information Present subfield is 1, the Non-SRG OBSS PD Max Offset field is not present.The SRG Information Present subfield of the SR control field may indicate whether the SRG OBSS PD Min Offset field, SRG OBSS PD Max Offset field, SRG BSS Color Bitmap field, and SRG Partial BSSID Bitmap field are present in the Spatial Reuse Parameter Set element. When the SRG Information Present subfield is 1, the SRG OBSS PD Min Offset field, SRG OBSS PD Max Offset field, SRG BSS Color Bitmap field, and SRG Partial BSSID Bitmap field are present. When the SRG Information Present subfield is 0, the SRG OBSS PD Min Offset field, SRG OBSS PD Max Offset field, SRG BSS Color Bitmap field, and SRG Partial BSSID Bitmap field are not present. The HESIGA_Spatial_reuse_value15_allowed subfield of the SR control field may indicate whether a non-AP STA associated with the AP that transmitted this element can set the TXVECTOR parameter SPATIAL_REUSE to PSR_AND_NON_SRG_OBSS_PD_PROHIBITED.

[0144] The PHY may provide an interface to the MAC. The MAC may provide an interface to the PHY. This interface may include a TXVECTOR and an RXVECTOR. The MAC may use the TXVECTOR to provide per-PPDU transmit parameters to the PHY. The PHY may use the RXVECTOR to notify the MAC of parameters of received PPDUs. The TXVECTOR may include one or more parameters. The TXVECTOR parameters may include LENGTH, DATARATE, PREAMBLE_TYPE, CH_BANDWIDTH_IN_NON_HT, CH_BANDWIDTH, BSS_COLOR, SPATIAL_REUSE, etc. The RXVECTOR parameters may include LENGTH, DATARATE, PREAMBLE_TYPE, CH_BANDWIDTH_IN_NON_HT, CH_BANDWIDTH, BSS_COLOR, SPATIAL_REUSE, etc.

[0145] The content of the Spatial Reuse field may be included in the TXVECTOR parameter SPATIAL_REUSE of the PPDU indicating spatial reuse information. PSR_DISALLOW may be used to prohibit PSR-based spatial reuse during the transmission of the corresponding PPDU. PSR_AND_NON_SRG_OBSS_PD_PROHIBITED may be used to prohibit both PSR-based spatial reuse and non-SRG OBSS PD-based spatial reuse during the transmission of the corresponding PPDU. The TXVECTOR parameter SPATIAL_REUSE and the RXVECTOR parameter SPATIAL_REUSE may indicate the spatial reuse parameter value. For example, the TXVECTOR parameter SPATIAL_REUSE may indicate any of PSR_DISALLOW, SR_RESTRICTED, SR_DELAYED, or PSR_AND_NON_SRG_OBSS_PD_PROHIBITED. A STA may set the TXVECTOR parameter SPATIAL_REUSE in a PPDU to SR_DELAYED if it allows OBSS PD based spatial reuse only after the end of the PPDU, or may set the TXVECTOR parameter SPATIAL_REUSE in a PPDU to SR_RESTRICTED if it allows OBSS PD based spatial reuse before the end of the PPDU.

[0146] A STA may classify a received PPDU as an inter-BSS PPDU if at least one of the following conditions is true: - The RXVECTOR parameter BSS_COLOR is not 0 and is not the BSS color of the BSS of which the STA is a member. - The PPDU is not equal to the BSSID[39:47] of the BSS to which the STA is associated or to the BSSID[39:47] of any other BSS in the same multi-BSSID set or co-host BSSID set to which the BSS belongs, and the RXVECTOR parameter GROUP_ID is 0. - The PPDU is a PPDU in which, if the partial BSS Color field of the most recent HE operation element is 1, the RXVECTOR parameter PARTIAL_AID[5:8] is not equal to the four LSBs of the BSS color advertised by the BSS of which the STA is a member, and dot11PartialBSSColorImplemented is true, and the RXVECTOR parameter GROUP_ID is equal to 63. - The PPDU is either a PPDU with the RXVECTOR parameter UPLINK_FLAG equal to 0 or a HE MU PPDU, and the STA is an AP. - The PPDU carries a frame with a BSSID field, but its value is not the BSSID of the BSS to which the STA is associated, nor the BSSID of any other BSS in the same multi-BSSID set or co-host BSSID set to which the BSS belongs, nor a wildcard BSSID. - The PPDU does not have a BSSID field, but carries a frame with both an RA field and a TA field, and neither value is equal to the BSSID of the BSS to which the STA is associated, nor the BSSID of any other BSS in the same multi-BSSID set or co-host BSSID set to which the BSS belongs.

[0147] A STA may classify a received PPDU as an intra-BSS PPDU if at least one of the following conditions is true: - The RXVECTOR parameter BSS_COLOR of the PPDU carrying the frame is the BSS color of the BSS of which the STA is a member, or the BSS color of the TDLS link to which the STA belongs if the STA is a non-AP associated STA. - The PPDU is a VHT PPDU, the RXVECTOR parameter PARTIAL_AID is equal to the BSSID[39:47] of the BSS to which the STA is associated or of another BSS in the same multi-BSSID set or co-host BSSID set to which that BSS belongs, and the RXVECTOR parameter GROUP_ID is equal to 0. The PPDU is a VHT PPDU, with the RXVECTOR parameter PARTIAL_AID[5:8] equal to the 4 LSBs of the BSS color announced by the BSS of which the STA is a member, with dot11PartialBSSColorImplemented equal to true, the RXVECTOR parameter GROUP_ID equal to 63, and the Partial BSS Color field of the most recent HE Operation element equal to 1. The PPDU carries a frame with an RA, TA, or BSSID field value equal to the BSSID of the BSS, or the BSSID of the BSS to which the STA is associated or of another BSS in the same multi-BSSID set or co-host BSSID set to which the BSS belongs. The PPDU does not have a TA field and carries a control frame with an RA field value that matches the saved TXOP holder address of the BSS to which the STA is associated or of another BSS in the same multi-BSSID set or co-host BSSID set to which the BSS belongs.

[0148] If a received PPDU satisfies both the intra-BSS and inter-BSS conditions based on the MAC address information of the frame included in the received PPDU, the received PPDU may be classified as an intra-PPDU. If a received PPDU satisfies the intra-BSS condition using the RXVECTOR parameter BSS_COLOR and also satisfies the inter-BSS condition using the MAC address information of the frame included in the PPDU, classification using the MAC address information may take precedence. If the STA determines that BSS color is disabled, the RXVECTOR parameter BSS_COLOR of the PPDU may not be used to classify the PPDU.

[0149] For example, an intra-BSS PPDU may be a PPDU received from a STA or AP belonging to the same BSS. An intra-BSS PPDU may be a PPDU received from a synchronized STA or AP. For example, an inter-BSS PPDU may be a PPDU received from a STA or AP belonging to a different BSS. An inter-BSS PPDU may be a PPDU received from an unsynchronized STA or AP. For example, in FIG. 2, the PPDU received by 204 from 202 or 203 may be an intra-BSS PPDU. For example, in FIG. 2, the PPDU received by 202 from 203 or 204 may be an intra-BSS PPDU. For example, in FIG. 2, the PPDU received by 204 from 207 or 206 may be an inter-BSS PPDU. For example, in FIG. 2, the PPDU received by 202 from 207 or 206 may be an inter-BSS PPDU. For example, in Fig. 2, the PPDU received by 207 from 202 or 204 may be an inter-BSS PPDU. For example, in Fig. 2, the PPDU received by 207 from 206 or 208 may be an intra-BSS PPDU. The inter-BSS PPDU may be an OBSS PPDU. The OBSS PPDU may be an inter-BSS PPDU. The inter-BSS PPDU may be referred to as an OBSS PPDU.

[0150] The PHY-RXSTART.indication primitive may notify the local MAC entity that the PHY has received a valid start of a PPDU containing a valid PHY header. The PHY-RXSTART.indication primitive may provide an RXVECTOR, which may represent a list of parameters that the PHY provides to the local MAC entity upon receiving a valid PHY header. The PHY-RXSTART.indication primitive may be generated from the local PHY entity to the MAC sublayer when the PHY successfully validates the PHY header at the start of a new PPDU. After generating the PHY-RXSTART.indication primitive, the PHY may remain busy on the physical medium (i.e., not generate a PHY-CCA.indication(IDLE) primitive) for the period of time necessary to transfer a frame of the specified LENGTH at the specified DATARATE. The PHY entity may issue the PHY-RXEARLYSIG.indication primitive to begin receiving the U-SIG field and identify the PPDU version based on the PHY Version Identifier field of the U-SIG field. The PHY may not issue either the PHY-RXEARLYSIG.indication primitive or the PHY-RXSTART.indication primitive in response to a PPDU that does not overlap with the primary channel unless the PHY of the AP receives an EHT TB PPDU requested by the AP. The PHY may issue both the PHY-RXEARLYSIG.indication primitive and the PHY-RXSTART.indication primitive in response to a PPDU requested by the AP.

[0151] The PHY-CCARESET.request primitive is a request from the MAC sublayer to the local PHY entity to reset the PHY to a state appropriate for the end of a received frame and may be a primitive to turn on / off IPI reporting using the IPI-STATE parameter. The IPI-STATE parameter may be present if dot11RadioMeasurementActivated is true. The Idle Power Indicator (IPI) may be a physical layer (PHY) indication of the total channel power (noise and interference) measured on the channel of the receive antenna connector when the STA is in idle state, i.e., not transmitting or receiving frames. The PHY-CCARESET.request primitive may be generated by the MAC sublayer for the local PHY entity at the end of NAV and at a specified time after each MAC slot boundary. The PHY-CCARESET.request primitive may also be generated by the MAC sublayer for the local PHY entity if the spatial reuse condition is met.

[0152] In non-SRG OBSS PD level operation, when the PHY (physical layer) of a STA issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, fourth, fifth, sixth, and seventh conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the STA has the TXVECTOR parameter SPATIAL REUSE present and has not set the TXVECTOR parameter SPATIAL_REUSE to the value PSR_AND_NON_SRG_OBSS_PD_PROHIBITED in all PPDUs that the STA transmitted in the current and previous beacon periods. The second condition is that the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element received from the associated AP is 0, or the STA is a non-AP STA that has not received a Spatial Reuse Parameter Set element from the associated AP, or the STA is an AP and the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element transmitted is 0, or the STA is an AP and has not transmitted a Spatial Reuse Parameter Set element.The third condition is that the received PPDU is an inter-BSS PPDU and not a non-HT PPDU carrying a response frame, or if the received PPDU contains a CTS, a PHY-CCA.indication transition from BUSY to IDLE occurs within the PIFS immediately preceding the received CTS, and that transition corresponds to the end of an inter-BSS PPDU containing an RTS frame that was discarded according to OBSS PD based spatial reuse. The fourth condition is that the STA is operating at the SRG OBSS PD level and the received PPDU is not an SRG PPDU, or the STA is not operating at the SRG OBSS PD level. The fifth condition is that the RXVECTOR parameter SPATIAL_REUSE (if present) of the received PPDU is not set to PSR_AND_NON_SRG_OBSS_PD_PROHIBITED. The sixth condition is that the received signal strength level measured from the L-STF or L-LTF field of the PPDU, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (if present and used to determine the PHY-CCA.indication) is below the non-SRG OBSS PD level. The seventh condition is that the (received) PPDU is not a non-HE PPDU carrying a frame with the RA field equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. In other words, in non-SRG OBSS PD level operation, if a STA receives a PPDU and multiple conditions are met, it may ignore the PPDU without updating its NAV.

[0153] In non-SRG OBSS PD level operation, a STA may not perform SR on the HE sounding NDP or HE TBfeedback NDP. In non-SRG OBSS PD level operation, if a frame is transmitted in a HE ER SU PPDU identified as an inter-BSS PPDU (the power of the L-STF / L-LTF symbols is boosted by 3 dB), the STA may subtract 3 dB from the received signal strength measured from the L-STF or L-LTF field of the PPDU, use it to determine the PHY-CCA.indication, compare it with the non-SRG OBSS PD level, and correct for the power difference. In non-SRG OBSS PD level operation, if the (received) PPDU is a HE SU PPDU or HE ER SU PPDU and the RXVECTOR parameter SPATIAL_REUSE indicates SR_DELAYED, a PHY-CCARESET.requestprimitive may be issued at the end of the PPDU. A STA may set the TXVECTOR parameter SPATIAL_REUSE in a PPDU to SR_DELAYED if it allows OBSS PD based spatial reuse only after the end of the PPDU. In non-SRG OBSS PD level operation, if a PHY-CCARESET.request primitive is issued before the end of the received PPDU and a TXOP is initiated within the duration of the received PPDU, the duration of the TXOP and the PPDU transmission within that TXOP may be limited to the duration of the received PPDU if the received PPDU is a HE MU PPDU and the RXVECTOR parameter SPATIAL_REUSE indicates SR_RESTRICTED. A STA may set the TXVECTOR parameter SPATIAL_REUSE in a PPDU to SR_RESTRICTED if it allows OBSS PD based spatial reuse before the end of the PPDU.A STA that ignores PPDUs in accordance with the procedure for non-SRG OBSS PD level operation may be considered to be performing non-SRG OBSS PD based spatial reuse.

[0154] In SRG OBSS PD level operation, when the PHY (physical layer) of a STA issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, and third conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the received PPDU is an SRG PPDU. The second condition is that the received signal strength level measured from the L-STF or L-LTF field, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (if present and used to determine the PHY-CCA.indication) of the PPDU is below the SRG OBSS PD level. The third condition is that the (received) PPDU is not a non-HE PPDU carrying a frame with the RA field equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. In other words, in SRG OBSS PD level operation, if a STA receives a PPDU and multiple conditions are met, it may ignore the PPDU without updating its NAV.

[0155] In SRG OBSS PD level operation, a STA may not perform SR on the HE sounding NDP or HE TB feedback NDP. In SRG OBSS PD level operation, if a frame is transmitted in a HE ER SU PPDU identified as an inter-BSS PPDU (the power of the L-STF / L-LTF symbols is boosted by 3 dB), the STA may subtract 3 dB from the received signal strength measured from the L-STF or L-LTF field of the PPDU, use it to determine the PHY-CCA.indication, compare it with the non-SRGO BSS PD level, and correct the power difference. In SRG OBSS PD level operation, if the (received) PPDU is a HE SU PPDU or HE ER SU PPDU and the RXVECTOR parameter SPATIAL_REUSE indicates SR_DELAYED, the PHY-CCARESET.request primitive may be issued at the end of the PPDU. In SRG OBSS PD level operation, if a PHY-CCARESET.request primitive is issued before the end of a received PPDU and a TXOP is started within the duration of the received PPDU, the duration of the TXOP and the PPDU transmission within that TXOP may be limited to the duration of the received PPDU if the received PPDU is a HE MU PPDU and the RXVECTOR parameter SPATIAL_REUSE indicates SR_RESTRICTED.

[0156] When using OBSS PD-based spatial reuse, a STA may maintain its OBSS PD level and adjust it according to the transmit power and the PPDU_BW value obtained from the received PPDU. The OBSS PD level may be set for both non-SRG OBSS PD level operation and SRG OBSS PD level operation. The OBSS PD level may be adjusted based on OBSS_PDmin, OBSS_PDmax, TX_PWRref, TX_PWR, and PPDU_BW. TX_PWRref may be a predefined value. For example, TX_PWRref may be defined as 21 dBm for non-AP STAs. TX_PWRref may be defined as 21 dBm or 25 dBm for AP STAs. TX_PWR may be the total transmit power (dBm) at the transmit antenna connectors of all antennas. PPDU_BW may be determined using the received RXVECTOR parameter. The PPDU_BW may be determined based on CH_BANDWIDTH if CH_BANDWIDTH is present in the received RXVECTOR parameters. The PPDU_BW may be determined based on CH_BANDWIDTH_IN_NOT_HT if CH_BANDWIDTH is not present but CH_BANDWIDTH_IN_NOT_HT is present in the received RXVECTOR parameters. The PPDU_BW may be determined based on DATARATE if CH_BANDWIDTH and CH_BANDWIDTH_IN_NOT_HT are present in the received RXVECTOR parameters. For example, if CH_BANDWIDTH or CH_BANDWIDTH_IN_NOT_HT indicates CBW20, HT_CBW20, or NON_HT_CBW20, the PPDU_BW may be 20 MHz. If CH_BANDWIDTH or CH_BANDWIDTH_IN_NOT_HT indicates either CBW40, HT_CBW40, or NON_HT_CBW40, the PPDU_BW may be 40 MHz.If CH_BANDWIDTH or CH_BANDWIDTH_IN_NOT_HT indicates CBW80, HE-CBW-PUNC80-PRI, or HE-CBW-PUNC80-SEC, the PPDU_BW may be 80 MHz. If CH_BANDWIDTH or CH_BANDWIDTH_IN_NOT_HT indicates CBW160, CBW80+80, HE-CBW-PUNC160-PRI20, HE-CBW-PUNC80+80-PRI20, HE-CBW-PUNC160-SEC40, or HE-CBW-PUNC80+80-SEC40, the PPDU_BW may be 160 MHz. If DATARATE indicates 1, 2, 5.5, or 11, the PPDU_BW may be 20 MHz. OBSS_PDmin may be referred to as Non-SRG OBSS PD Min. They may also be referred to as OBSS_PDmax and Non-SRG OBSS PD Max. Non-SRG OBSS PDMin and Non-SRG OBSS PD Max may be determined using the Non-SRG OBSS PD SR Disallowed field and / or the Non-SRG Offset Present field and / or the Non-SRG OBSS PD Max Offset field in the Spatial Reuse Parameter Set element. For example, when a Spatial Reuse Parameter Set element is not received, Non-SRG OBSS PD Min may be −82 (dBm) and Non-SRG OBSS PD Max may be −62 (dBm). For example, if the Non-SRG OBSS PD SR Disallowed field in the Spatial Reuse Parameter Set element indicates 0 and the Non-SRG Offset Present field indicates 0, the Non-SRG OBSS PD Min may be −82 (dBm) and the Non-SRG OBSS PD Max may be −62 (dBm).For example, when the Non-SRG OBSS PD SR Disallowed field in the Spatial Reuse Parameter Set element indicates 0 and the Non-SRG Offset Present field indicates 1, Non-SRG OBSS PD Min may be -82 (dBm) and Non-SRG OBSS PD Max may be -82 + Non-SRG OBSS PD Max Offset (dBm). For example, when the Non-SRG OBSS PD SR Disallowed field in the Spatial Reuse Parameter Set element indicates 1 and the Non-SRG Offset Present field is not present, Non-SRG OBSS PD Min may be -82 (dBm) and Non-SRG OBSS PD Max may be -82 (dBm). OBSS_PDmin may also be referred to as SRG OBSS PD Min, OBSS_PDmax, or SRG OBSS PD Max. The SRG OBSS PD Min and SRG OBSS PD Max may be determined using the SRG Information Present field and / or the SRG OBSS PD Min Offset field and / or the SRG OBSS PD Max Offset field in the Spatial Reuse Parameter Set element. For example, if the Spatial Reuse Parameter Set element is not received or if SRG information is not present, the STA cannot determine that the PPDU is SRG, and therefore does not need to determine the SRG OBSS PD Min and SRG OBSS PD Max. In other words, the SRG OBSS PD Min and SRG OBSS PD Max may be N / A. For example, if the SRG Information Present field is 0, the STA does not need to determine the SRG OBSS PD Min and SRG OBSS PD Max. In other words, the SRG OBSS PD Min and SRG OBSS PD Max may be N / A.For example, when the SRGInformationPresent field is 1, the SRG OBSS PD Min may be −82+SRG OBSS PD Min Offset (dBm), and the SRG OBSS PD Max may be −82+SRG OBSS PD Man Offset (dBm).

[0157] If the STA ignores the inter-BSS PPDU, the STA may resume EDCAF procedures after the PHY-CCARESET.request primitive is sent, unless the medium is indicated as BUSY.

[0158] STAs following non-SRG OBSS PD level operation and SRG OBSS PD level operation may additionally observe the following conditions: If the RXVECTOR parameter SPATIAL_REUSE of an EHT SU transmission indicates SR_DELAYED, the PHY-CCARESET.request primitive may be issued at the end of the PPDU. If the PHY-CCARESET.request primitive is issued before the end of the received PPDU and a TXOP is initiated within the duration of the received PPDU, and the received PPDU is an EHT MU PPDU addressed to multiple STAs and the RXVECTOR parameter SPATIAL_REUSE indicates SR_RESTRICTED, the duration of the TXOP and the PPDU transmissions within that TXOP may be limited to the duration of the received PPDU. The received signal strength level used to determine whether the signal is below the non-SRG OBSS PD level or the SRG OBSS PD level may be measured in dBm / 20 MHz from the L-STF or L-LTF field in at least one of the nonpunctured 20 MHz subchannels of the PPDU, or from the PHY SYNC, shortSYNC, or LongPHY SYNC field, if present, used to determine the PHY-CCA.indication. Which of these 20 MHz subchannels the received signal strength level is measured from may vary depending on the implementation.

[0159] In one aspect of the present invention, an NPCA (Non Primary Channel Access) primary channel may be defined. The NPCA primary channel may be a channel that is accessed while the primary channel is busy. The NPCA primary channel may be a channel that is accessed by OBSS traffic while the primary channel is busy. The NPCA primary channel may be called something other than the NPCA primary channel. For example, the NPCA primary channel may be called a secondary primary channel.

[0160] In one aspect of the present invention, an AP and / or STA may perform Non-Primary Channel Access (NPCA). NPCA may be an operation for accessing another channel while the primary channel is busy due to OBSS traffic (i.e., while it is occupied by OBSS traffic). For example, the OBSS traffic may be a PPDU received from the OBSS. The OBSS traffic may be an inter-BSS PPDU. The AP and / or STA may perform a backoff procedure on another channel while the primary channel is busy due to OBSS traffic. For example, the channel on which the backoff procedure is performed while the primary channel is busy due to OBSS traffic may be referred to as the NPCA primary channel, secondary primary channel, etc. The name of the channel on which the backoff procedure is performed while the primary channel is busy may be other names. In other words, when the primary channel becomes busy due to OBSS traffic, the AP and / or STA may perform a backoff procedure on the NPCA primary channel. The AP and / or STA may perform a backoff procedure on the NPCA primary channel while the NAV is set on the primary channel by the OBSS PPDU. Once the backoff procedure on the NPCA primary channel is complete, the AP and / or STA may transmit on one or more channels, including the NPCA primary channel but excluding the primary channel. The AP and / or STA may switch to the primary channel before the NAV period ends. The AP may transmit information related to NPCA primary channel access in a frame. The STA may determine an action related to NPCA primary channel access based on the frame received from the AP.

[0161] If the primary channel is idle, the STA or AP may transmit on one or more channels including the primary channel. If the primary channel is busy, the STA or AP may sense on the NPCA primary channel, and if the NPCA primary channel is idle, it may transmit on one or more channels that include the NPCA primary channel but do not include the primary channel. If the primary channel is busy due to OBSS traffic, the STA or AP may sense on the NPCA primary channel, and if the NPCA primary channel is idle, it may transmit on one or more channels that include the NPCA primary channel but do not include the primary channel. For example, the OBSS traffic may be an OBSS PPDU. The STA or AP may transmit on one or more channels that include the NPCA primary channel but do not include the primary channel. Note that "may transmit" may also be expressed as "have the right to transmit." The STA or AP may receive on one or more channels including the primary channel. The STA or AP may receive on one or more channels that do not include the primary channel but include at least the NPCA primary channel.

[0162] In NPCA, a STA or AP may transmit using multiple channels. When transmitting using multiple channels in NPCA, the STA or AP may perform a backoff procedure on the NPCA primary channel and perform sensing for a predetermined period on the NPCA secondary channel immediately before transmission. The NPCA secondary channel may be a channel other than the NPCA primary channel for transmitting using multiple channels in NPCA. The NPCA secondary channel may be defined as an NPCA secondary 20 MHz channel, an NPCA secondary 40 MHz channel, or an NPCA secondary 80 MHz channel. The NPCA secondary 20 MHz channel may be a 20 MHz channel related to the NPCA primary channel. For example, when transmitting in a 40 MHz bandwidth in NPCA, the STA or AP may transmit using the NPCA primary channel and the NPCA secondary 20 MHz channel. The NPCA secondary 40 MHz channel may be a 40 MHz channel related to the NPCA primary channel. For example, when transmitting in an 80 MHz bandwidth in the NPCA, a STA or AP may transmit using an NPCA primary channel, an NPCA secondary 20 MHz channel, and an NPCA secondary 40 MHz channel. The NPCA secondary 40 MHz channel may consist of two 20 MHz channels. The NPCA secondary 80 MHz channel may be an 80 MHz channel associated with the NPCA primary channel.For example, when transmitting in a 160 MHz bandwidth in NPCA, a STA or AP may transmit using an NPCA primary channel, an NPCA secondary 20 MHz channel, an NPCA secondary 40 MHz channel, and an NPCA secondary 80 MHz channel. The NPCA secondary 80 MHz channel may consist of four 20 MHz channels. The NPCA secondary channel may be referred to by a name other than the NPCA secondary channel. For example, the NPCA secondary channel may be referred to as a secondary secondary channel. The NPCA secondary 20 MHz channel may be referred to by a name other than the NPCA secondary 20 MHz channel. For example, the NPCA secondary 20 MHz channel may be referred to as a secondary secondary 20 MHz channel. The NPCA secondary 40 MHz channel may be referred to by a name other than the NPCA secondary 40 MHz channel. For example, the NPCA secondary 40 MHz channel may be referred to as a secondary secondary 40 MHz channel. The NPCA secondary 80 MHz channel may be referred to by a name other than the NPCA secondary 80 MHz channel. For example, the NPCA secondary 80 MHz channel may be referred to as the secondary secondary 80 MHz channel.

[0163] FIG. 13 illustrates an example of a backoff procedure on an NPCA primary channel by a STA according to one aspect of this embodiment. 1301, 1302, 1303, 1304, 1305, 1306, 1307, and 1308 may each be a 20 MHz channel. FIG. 13 may also illustrate a STA operating at 160 MHz. 1301 may be the primary channel. 1306 may be the NPCA primary channel. 1309 may be a frame received by the STA transmitted by another STA or AP. 1309 may be a frame received by the STA transmitted by a STA or AP belonging to an OBSS. For example, 1309 may be an RTS frame. 1309 may be a CTS frame. 1309 may be a Data frame. 130 may be a NAV. 1311 may be a backoff procedure (backoff counter, contention window). 1312 may be a frame transmission. When the STA receives 1309 in 1301, it may set 1310 in 1301 for the period indicated by the Duration field of 1309. When 1310 is set in 1301, the STA may transition to 1306. That is, the STA may dynamically switch from the primary channel to the NPCA primary channel. When the STA transitions to 1306, it may start 1311 in 1306. When 1311 is completed, the STA may perform 1312. Here, for example, the STA performing the operation in FIG. 13 is 204 in FIG. 2, and 1309 may be a frame transmitted by 207 in FIG. 2. FIG. 13 may be a diagram of an AP operating at 160 MHz. For example, FIG. 13 is the operation of 202 in FIG. 2, and 1309 may be a frame transmitted by 207. 1312 may be transmitted using multiple channels. For example, 1312 may be a transmission with a channel width of 80 MHz transmitted using 1308, 1307, 1306, and 1305. Here, 1308, 1307, and 1305 may be NPCA secondary channels.The 80 MHz transmission may be transmission using the NPCA primary channel 1306, the NPCA secondary 20 MHz channel 1305, and the NPCA secondary 40 MHz channel consisting of 1307 and 1308.

[0164] An AP may transmit a frame including an information element including information related to non-primary channel access. When performing non-primary channel access, the AP may transmit a frame including an information element including information related to non-primary channel access. The AP may transmit a frame including an information element including information related to non-primary channel access to indicate to STAs in a BSS whether non-primary channel access is enabled or disabled. When an AP does not perform non-primary channel access in its own BSS, it may not include an information element including information related to non-primary channel access in the frame it transmits. For example, an information element including information related to non-primary channel access may be referred to as an NPCA operation element. For example, an information element including information related to non-primary channel access may be referred to as a UHR operation element. An information element including information related to non-primary channel access may be referred to by a name other than the above. An element ID for the NPCA operation element may be set. An element ID for the UHR operation element may be set. For example, the NPCA operation element may indicate information for non-primary channel access. The NPCA operation element may be composed of one or more fields. The NPCA operation element may include a field indicating the Element ID.The NPCA operation element may include a field indicating whether Non-Primary Channel Access is enabled or disabled. The NPCA operation element may include a field for indicating the position of the NPCA primary channel for Non-Primary Channel Access. The NPCA operation element may include a field for indicating the channel width for Non-Primary Channel Access. Fields other than those described above may be included in the NPCA operation element. For example, a STA may perform Non-Primary Channel Access when it receives a frame including an NPCA operation element from an AP. When it receives a frame including an NPCA operation element from an AP, it may perform Non-Primary Channel Access using the information indicated in the fields of the NPCA operation element. When it receives a frame including an NPCA operation element from an AP and indicates that Non-Primary Channel Access is enabled, it may perform Non-Primary Channel Access. When it does not receive a frame including an NPCA operation element from an AP, it does not perform Non-Primary Channel Access. When it receives a frame including an NPCA operation element from an AP and indicates that Non-Primary Channel Access is disabled, it does not perform Non-Primary Channel Access. For example, the UHR operation element may indicate information for controlling a UHR STA. For example, the UHR operation element may indicate information for Non Primary Channel Access. The UHR operation element may be composed of one or more fields.The UHR operation element may include a field indicating an Element ID. The UHR operation element may include a field indicating whether information related to Non-Primary Channel Access is included in the UHR operation element. The UHR operation element may include a field indicating whether Non-Primary Channel Access is enabled or disabled. The UHR operation element may include a field for indicating the location of the NPCA primary channel for Non-Primary Channel Access. If the UHR operation element indicates that information related to Non-Primary Channel Access is included in the UHR operation element, the UHR operation element may include a field for indicating the location of the NPCA primary channel for Non-Primary Channel Access. The UHR operation element may include a field for indicating the channel width for Non-Primary Channel Access. If the UHR operation element indicates that information related to Non-Primary Channel Access is included in the UHR operation element, the UHR operation element may include a field for indicating the channel width for Non-Primary Channel Access. Fields other than those described above may also be included in the UHR operation element. For example, a STA may perform Non-Primary Channel Access when it receives a frame including a UHR operation element from an AP. When a STA receives a frame including a UHR operation element from an AP, the STA may perform Non Primary Channel Access using the information indicated in the UHR operation element field.A STA may perform Non-Primary Channel Access if it receives a frame including a UHR operation element from the AP and the UHR operation element indicates that Non-Primary Channel Access is enabled. A STA does not perform Non-Primary Channel Access if it does not receive a frame including a UHR operation element from the AP. A STA does not perform Non-Primary Channel Access if it receives a frame including a UHR operation element from the AP and the UHR operation element indicates that Non-Primary Channel Access is disabled. A STA may perform Non-Primary Channel Access if the received UHR operation element indicates that information related to Non-Primary Channel Access is included in the UHR operation element. A STA does not perform Non-Primary Channel Access if the received UHR operation element indicates that information related to Non-Primary Channel Access is not included in the UHR operation element.

[0165] For example, in FIG. 1 , 102 may transmit a frame including an information element containing information related to Non-Primary Channel Access to STAs in BSS (101). 103 and 104 may receive a frame including an information element containing information related to Non-Primary Channel Access. That is, 102 may perform Non-Primary Channel Access based on the transmitted information related to Non-Primary Channel Access. 103 and 104 may perform Non-Primary Channel Access using the received information related to Non-Primary Channel Access. For example, 102 may not include information related to Non-Primary Channel Access in the frame it transmits. 103 and 104 do not receive a frame including an information element containing information related to Non-Primary Channel Access from 102 and do not perform Non-Primary Channel Access. That is, if 102 does not transmit a frame including an information element containing information related to Non-Primary Channel Access, 102, 103, and 104 do not perform Non-Primary Channel Access. For example, 102 may transmit a frame including an NPCA operation element to STAs in BSS (101). 103 and 104 may receive a frame including an NPCA operation element. That is, 102 may perform Non-Primary Channel Access based on the transmitted NPCA operation element. 103 and 104 may perform Non-Primary Channel Access using the received NPCA operation element. 102 may indicate whether Non-Primary Channel Access is enabled or disabled in the NPCA operation element.103 and 104 may determine whether Non-Primary Channel Access is enabled or disabled based on the received NPCA operation element. For example, 102 may transmit a frame including a UHR operation element to a STA in BSS (101). 103 and 104 may receive a frame including a UHR operation element. When 102 indicates that Non-Primary Channel Access is enabled for a STA belonging to 101, 102 indicates that information related to Non-Primary Channel Access is present in a field indicating whether information related to Non-Primary Channel Access is present in the UHR operation element. When 102 indicates that information related to Non-Primary Channel Access is present in a field indicating whether information related to Non-Primary Channel Access is present in the received UHR operation element, 103 and 104 may perform Non-Primary Channel Access. When 102 indicates that Non-Primary Channel Access is disabled for a STA belonging to 101, 102 indicates that information related to Non-Primary Channel Access is not present in a field indicating whether information related to Non-Primary Channel Access is present in the UHR operation element. 103 and 104 do not perform non-primary channel access if the field indicating whether or not information related to non-primary channel access exists in the received UHR operation element indicates that information related to non-primary channel access does not exist. Here, 103 and 104 may be UHR STAs.For example, when 103 is a UHR STA and 104 is an EHT STA, if 103 and 104 receive a frame including an information element containing information related to Non Primary Channel Access transmitted by 102, 103 may be able to obtain the information related to Non Primary Channel Access, but 104 may not be able to obtain the information related to Non Primary Channel Access. When 103 is a UHR STA and 104 is an EHT STA, if 103 and 104 receive a frame including an information element containing information related to Non Primary Channel Access transmitted by 102, 103 and 104 may be able to obtain the information related to Non Primary Channel Access.

[0166] A STA or AP may determine whether a frame transmitted by an AP belonging to another BSS includes an information element containing information related to Non-Primary Channel Access. For example, in FIG. 2, 204 and 202 may belong to a different BSS from 206. 206 may transmit a frame including an information element containing information related to Non-Primary Channel Access to STAs belonging to its own BSS (206). 204 and 202 receive a frame including an information element containing information related to Non-Primary Channel Access transmitted by 206, and can learn information related to Non-Primary Channel Access of a BSS (205) different from the BSS (201) to which they belong. For example, if the frame transmitted by 206 includes an information element containing information related to Non-Primary Channel Access, 205 may determine that Non-Primary Channel Access will be performed. For example, if the frame transmitted by 206 does not include an information element containing information related to Non-Primary Channel Access, 205 may determine that Non-Primary Channel Access will not be performed.

[0167] The TXVECTOR parameter may include information related to Non-Primary Channel Access. For example, the information related to Non-Primary Channel Access included in the TXVECTOR parameter may be referred to as NON_PRIMARY_CHANNEL_ACCESS. The information related to Non-Primary Channel Access included in the TXVECTOR parameter may be referred to as the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS. The RXVECTOR parameter may include information related to Non-Primary Channel Access. For example, the information related to Non-Primary Channel Access included in the RXVECTOR parameter may be referred to as NON_PRIMARY_CHANNEL_ACCESS. The information related to Non-Primary Channel Access included in the RXVECTOR parameter may be referred to as the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS. NON_PRIMARY_CHANNEL_ACCESS may indicate that Non-Primary Channel Access is enabled. NON_PRIMARY_CHANNEL_ACCESS may indicate that Non-Primary Channel Access is disabled. NON_PRIMARY_CHANNEL_ACCESS may indicate that Non-Primary Channel Access is prohibited. For example, a STA or AP may set the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS to NPCA_ENABLED to indicate that Non-Primary Channel Access is enabled.That is, when a STA or AP sets the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS to NPCA_ENABLED, it may be a case where the STA or AP enables Non-Primary Channel Access. For example, the STA or AP may set the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS to NPCA_DISABLED to indicate that Non-Primary Channel Access is disabled. That is, when a STA or AP sets the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS to NPCA_DISABLED, it may be a case where the STA or AP disables Non-Primary Channel Access. For example, the STA or AP may set the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS to NPCA_PROHIBIT to indicate that Non-Primary Channel Access is prohibited. That is, when a STA or AP sets the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS to NPCA_PROHIBIT, it may be a case where the STA or AP prohibits Non-Primary Channel Access. For example, if the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of a received PPDU is set to NPCA_ENABLED, the STA or AP may determine that the STA or AP that sent the PPDU has Non Primary Channel Access enabled. For example, if the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of a received PPDU is set to NPCA_DISABLED, the STA or AP may determine that the STA or AP that sent the PPDU has Non Primary Channel Access disabled.For example, if NPCA_PROHIBIT is set in the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of a received PPDU, the STA or AP may determine that the STA or AP that transmitted the PPDU prohibits Non-Primary Channel Access. If the STA or AP does not perform Non-Primary Channel Access, the STA or AP may not include NON_PRIMARY_CHANNEL_ACCESS in the TXVECTOR parameter. If NON_PRIMARY_CHANNEL_ACCESS is not present in the RXVECTOR parameter of a received PPDU, the STA or AP may determine that the STA or AP that transmitted the PPDU does not perform Non-Primary Channel Access.

[0168] For example, in FIG. 1 , when 102 transmits a PPDU with the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_ENABLED, 102 may indicate that Non-Primary Channel Access is enabled. When NPCA_ENABLED is set to the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of a PPDU received from 102, 103 and 104 may determine that Non-Primary Channel Access is enabled. When 103 transmits a PPDU with the TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_ENABLED, 103 may indicate that Non-Primary Channel Access is enabled. When NPCA_ENABLED is set to the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of a PPDU received from 103, 102 may indicate that Non-Primary Channel Access is enabled. When NPCA_ENABLED is set to the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of a PPDU received from 103, 102 and 104 may determine that Non-Primary Channel Access is enabled. When 102 transmits a PPDU with TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_DISABLED, 102 may indicate that Non-Primary Channel Access is disabled. When 103 and 104 receive a PPDU with RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_DISABLED, 102 may determine that Non-Primary Channel Access is disabled. When 103 transmits a PPDU with TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_DISABLED, 103 may indicate that Non-Primary Channel Access is disabled.When the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the PPDU received from 103 is set to NPCA_DISABLED, 102 and 104 may determine that Non-Primary Channel Access is disabled. When 102 transmits a PPDU with TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_PROHIBIT, 102 may indicate that Non-Primary Channel Access is prohibited. When 103 and 104 receive a PPDU with RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_PROHIBIT, 102 may determine that Non-Primary Channel Access is prohibited. When 103 transmits a PPDU with TXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS set to NPCA_PROHIBIT, 103 may indicate that Non-Primary Channel Access is prohibited. When NPCA_PROHIBIT is set in the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the PPDU received from 103, 102 and 104 may determine that 103 prohibits non-primary channel access.

[0169] A STA or AP may receive a PPDU transmitted by a STA or AP belonging to another BSS, and determine the Non-Primary Channel Access setting of the STA or AP that transmitted the PPDU from the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) of the received PPDU. For example, in FIG. 2, 204 may belong to a different BSS from 206 and 207. 204 may determine the Non-Primary Channel Access setting of 207 from the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) of the PPDU received from 207. 204 may determine that 207 has Non-Primary Channel Access enabled if the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the PPDU received from 207 is set to NPCA_ENABLED. 204 may determine the setting of Non-Primary Channel Access of 206 from the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) of the PPDU received from 206. If NPCA_PROHIBIT is set in the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the PPDU received from 207, 204 may determine that 207 prohibits Non-Primary Channel Access. 202 may belong to a different BSS from 206 and 207. 202 may determine the setting of Non-Primary Channel Access of 207 from the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) of the PPDU received from 207. If NPCA_ENABLED is set in the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the PPDU received from 202, 207 may determine that Non-Primary Channel Access is enabled.202 may determine the setting of Non Primary Channel Access of 206 from the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) of the PPDU received from 206. If NPCA_PROHIBIT is set in the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the PPDU received from 207, 202 may determine that 207 prohibits Non Primary Channel Access.

[0170] A STA or AP does not have to determine not to update its NAV based solely on the conditions for Non-SRG OBSS PD level operation. In addition to the conditions for Non-SRG OBSS PD level operation, a STA or AP may not update its NAV when all or any of the following conditions are met: - A non-AP STA has not received an information element related to Non-Primary Channel Access from its associated AP, or a STA that is an AP has not sent an information element related to Non-Primary Channel Access. - The RXVECTOR parameter NON_PRIMARY_CHANNLE_ACCESS (if present) in the received PPDU is set to NPCA_ENABLED.

[0171] The associated AP of an STA may be an AP belonging to the same BSS. The associated AP of an STA may be a synchronized AP. For example, in FIG. 2 , the associated AP of 204 may be 202. The associated AP of 207 may be 206. The non-associated AP of an STA may be an AP belonging to a different BSS. The non-associated AP of an STA may be a non-synchronized AP. For example, in FIG. 2 , the non-associated AP of 204 may be 206. The non-associated AP of 207 may be 202.

[0172] In non-SRG OBSS PD level operation, the STA and / or AP may determine whether to update the NAV by considering information related to non-primary channel access. The information related to non-primary channel access may be an information element related to non-primary channel access. For example, the information element related to non-primary channel access may be an NPCA operation element, a UHR operation element, etc. In non-SRG OBSS PD level operation, when the PHY (physical layer) of a STA or AP issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA or AP may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, fourth, fifth, sixth, seventh, and eighth conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the STA has the TXVECTOR parameter SPATIAL REUSE present and has not set the TXVECTOR parameter SPATIAL_REUSE to the value PSR_AND_NON_SRG_OBSS_PD_PROHIBITED in all PPDUs that the STA has transmitted in the current Beacon period and the previous Beacon period.The second condition is when the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element received from the associated AP is 0, or the STA is a non-AP STA that has not received a Spatial Reuse Parameter Set element from the associated AP, or the STA is an AP and the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element transmitted is 0, or the STA is an AP and has not transmitted a Spatial Reuse Parameter Set element. The third condition is when the received PPDU is an inter-BSS PPDU and not a non-HT PPDU carrying a response frame, or when the received PPDU contains a CTS, a PHY-CCA.indication transition from BUSY to IDLE occurs within the PIFS immediately preceding the received CTS, and the transition corresponds to the end of the inter-BSS PPDU containing an RTS frame that was discarded according to OBSS PD based spatial reuse. The fourth condition is that the STA is operating at the SRG OBSS PD level and the received PPDU is not an SRG PPDU, or the STA is not operating at the SRG OBSS PD level. The fifth condition is that the RXVECTOR parameter SPATIAL_REUSE (if present) of the received PPDU is not set to PSR_AND_NON_SRG_OBSS_PD_PROHIBITED. The sixth condition is that the received signal strength level measured from the L-STF or L-LTF field of the PPDU, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (whichever is present and used to determine the PHY-CCA.indication) is below the non-SRG OBSS PD level.The seventh condition is that the (received) PPDU is not a non-HE PPDU carrying a frame whose RA field is equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. The eighth condition may be that the STA does not receive an information element related to Non-Primary Channel Access from its associated AP, or that the STA that is an AP does not transmit an information element related to Non-Primary Channel Access. In other words, if the STA receives an information element related to Non-Primary Channel Access from its associated AP, or if the STA that is an AP transmits an information element related to Non-Primary Channel Access, the eighth condition is not met, and the NAV may be updated. If the eighth condition is not met, the STA or AP may update the NAV and perform Non-Primary Channel Access. If the STA does not receive an information element related to Non-Primary Channel Access from an associated AP, or if the STA that is an AP does not transmit an information element related to Non-Primary Channel Access, the eighth condition is met, and if all other conditions are met, the NAV may not be updated. The eighth condition may be configured as a single condition together with the other conditions. For example, the eighth condition may be configured as a single condition together with the second condition.

[0173] For example, "no information element related to Non-Primary Channel Access has been received" may mean that a frame including an NPCA operation element has not been received. "no information element related to Non-Primary Channel Access has not been transmitted" may mean that a frame including an NPCA operation element has not been transmitted. For example, "no information element related to Non-Primary Channel Access has not been received" may mean that an NPCA operation element has been received and the NPCA operation element indicates that the operation is invalid. For example, "no information element related to Non-Primary Channel Access has not been transmitted" may mean that an NPCA operation element has been transmitted and the NPCA operation element indicates that the operation is invalid. For example, "no information element related to Non-Primary Channel Access has not been received" may mean that a frame including a UHR operation element has not been received. For example, "no information element related to Non-Primary Channel Access has not been transmitted" may mean that a frame including a UHR operation element has not been transmitted. For example, "no information element related to Non-Primary Channel Access has not been received" may mean that a UHR operation element has been received and the field indicating whether or not information related to Non-Primary Channel Access is present in the UHR operation element indicates that information related to Non-Primary Channel Access is not present.For example, "no information element related to Non Primary Channel Access has been sent" may mean that an NPCA operation element has been sent and the field indicating whether or not information related to Non Primary Channel Access exists in the UHR operation element indicates that no information related to Non Primary Channel Access exists.

[0174] The STA may receive an information element regarding Non-Primary Channel Access using the wireless transceiver unit SU6. The STA may determine, using the frame processing unit SU7, whether or not it has received an information element regarding Non-Primary Channel Access from an AP belonging to the same BSS. The STA may not update its NAV if multiple conditions are met. One of the multiple conditions may be that it has not received an information element regarding Non-Primary Channel Access from an AP belonging to the same BSS. The AP may transmit an information element regarding Non-Primary Channel Access using the wireless transceiver unit AU6. The AP may not update its NAV if multiple conditions are met. One of the multiple conditions may be that it has not transmitted an information element regarding Non-Primary Channel Access.

[0175] A STA or AP may update its NAV if the Duration field of a received frame is greater than the current NAV value. A STA or AP may update its NAV if the Duration field of a received frame is greater than the current NAV value and at least one of multiple conditions is not met. A STA or AP may not update its NAV if multiple conditions are met, even if the Duration field of a received frame is greater than the current NAV value. In OBSS PD-based spatial reuse, a STA or AP may update its NAV if the Duration field of a received frame is greater than the current NAV value and at least one of multiple conditions is not met. In OBSS PD-based spatial reuse, a STA or AP may not update its NAV if multiple conditions are met, even if the Duration field of a received frame is greater than the current NAV value. A STA or AP that receives at least one valid frame in a PSDU may update its NAV using information in the valid Duration field in the PSDU.

[0176] In non-SRG OBSS PD level operation, the STA and / or AP may determine whether to update the NAV by taking into account information related to non-primary channel access. The information related to non-primary channel access may be an RXVECTOR parameter related to non-primary channel access. For example, the RXVECTOR parameter may be NON_PRIMARY_CHANNEL_ACCESS. In non-SRG OBSS PD level operation, when the PHY (physical layer) of a STA or AP issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA or AP may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, fourth, fifth, sixth, seventh, and eighth conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the STA has the TXVECTOR parameter SPATIAL REUSE present and has not set the TXVECTOR parameter SPATIAL_REUSE to the value PSR_AND_NON_SRG_OBSS_PD_PROHIBITED in all PPDUs that the STA has transmitted in the current Beacon period and the previous Beacon period.The second condition is when the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element received from the associated AP is 0, or the STA is a non-AP STA that has not received a Spatial Reuse Parameter Set element from the associated AP, or the STA is an AP and the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element transmitted is 0, or the STA is an AP and has not transmitted a Spatial Reuse Parameter Set element. The third condition is when the received PPDU is an inter-BSS PPDU and not a non-HT PPDU carrying a response frame, or when the received PPDU contains a CTS, a PHY-CCA.indication transition from BUSY to IDLE occurs within the PIFS immediately preceding the received CTS, and the transition corresponds to the end of the inter-BSS PPDU containing an RTS frame that was discarded according to OBSS PD based spatial reuse. The fourth condition is that the STA is operating at the SRG OBSS PD level and the received PPDU is not an SRG PPDU, or the STA is not operating at the SRG OBSS PD level. The fifth condition is that the RXVECTOR parameter SPATIAL_REUSE (if present) of the received PPDU is not set to PSR_AND_NON_SRG_OBSS_PD_PROHIBITED. The sixth condition is that the received signal strength level measured from the L-STF or L-LTF field of the PPDU, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (whichever is present and used to determine the PHY-CCA.indication) is below the non-SRG OBSS PD level.The seventh condition is that the (received) PPDU is not a non-HE PPDU carrying a frame whose RA field is equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. The eighth condition is that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) is not set to NPCA_ENABLED. That is, the eighth condition may be that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_ENABLED, the eighth condition is not met, and the NAV may be updated. If the eighth condition is not met, the STA or AP may update its NAV and perform non-primary channel access. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or if the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU, the eighth condition is met, and if all other conditions are met, the NAV may not be updated. The eighth condition may be configured as a single condition together with other conditions. For example, the eighth condition may be configured as a single condition together with the sixth condition. The PPDU related to the eighth condition may be any PPDU. The PPDU related to the eighth condition may be any PPDU received from a STA or AP belonging to the same BSS as the STA or AP.The PPDU related to the eighth condition may be any PPDU received from a STA or AP belonging to a different BSS (OBSS) from the 8th condition. The PPDU related to the eighth condition may be the same PPDU as the 3rd condition and / or the 5th condition. The PPDU related to the 8th condition may be a different PPDU from the 3rd condition and / or the 5th condition.

[0177] In Non-SRG OBSS PD level operation, the STA and / or AP may determine whether to update the NAV by taking into account information related to Non-Primary Channel Access. The information related to Non-Primary Channel Access may be an information element related to Non-Primary Channel Access and an RXVECTOR parameter related to Non-Primary Channel Access. For example, the information element related to Non-Primary Channel Access may be an NPCA operation element, a UHR operation element, etc. For example, the RXVECTOR parameter related to Non-Primary Channel Access may be the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS, etc. In non-SRG OBSS PD level operation, when the PHY (physical layer) of a STA or AP issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA or AP may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, fourth, fifth, sixth, seventh, eighth, and ninth conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer).The first condition is that the STA has the TXVECTOR parameter SPATIAL REUSE present and has not set the TXVECTOR parameter SPATIAL_REUSE to the value PSR_AND_NON_SRG_OBSS_PD_PROHIBITED in all PPDUs that the STA transmitted in the current and previous beacon periods. The second condition is that the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element received from the associated AP is 0, or the STA is a non-AP STA that has not received a Spatial Reuse Parameter Set element from the associated AP, or the STA is an AP and the Non-SRG OBSS PD SR Disallowed subfield of the most recent Spatial Reuse Parameter Set element that it transmitted is 0, or the STA is an AP and has not transmitted a Spatial Reuse Parameter Set element. The third condition is that the received PPDU is an inter-BSS PPDU and not a non-HT PPDU carrying a response frame, or if the received PPDU contains a CTS, a PHY-CCA.indication transition from BUSY to IDLE occurs within the PIFS immediately preceding the received CTS, and that transition corresponds to the end of an inter-BSS PPDU containing an RTS frame that was discarded according to OBSS PD based spatial reuse. The fourth condition is that the STA is operating at the SRG OBSS PD level and the received PPDU is not an SRG PPDU, or the STA is not operating at the SRG OBSS PD level. The fifth condition is that the RXVECTOR parameter SPATIAL_REUSE (if present) of the received PPDU is not set to PSR_AND_NON_SRG_OBSS_PD_PROHIBITED.The sixth condition is that the received signal strength level measured from the L-STF or L-LTF field, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (if present and used to determine the PHY-CCA.indication) of the PPDU is below the non-SRG OBSS PD level. The seventh condition is that the (received) PPDU is not a non-HE PPDU carrying a frame with an RA field equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. The eighth condition may be that the STA has not received an information element related to Non-Primary Channel Access from its associated AP, or that the STA, which is an AP, has not transmitted an information element related to Non-Primary Channel Access. That is, if the STA receives an information element related to Non-Primary Channel Access from an associated AP, or if the STA that is an AP transmits an information element related to Non-Primary Channel Access, the eighth condition is not met, and the NAV may be updated. If the eighth condition is not met, the STA or AP may update the NAV and perform Non-Primary Channel Access. The eighth condition may be configured as a single condition together with another condition. For example, the eighth condition may be configured as a single condition together with the second condition. A ninth condition may be that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) is not set to NPCA_ENABLED.That is, the ninth condition may be satisfied when the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or when the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_ENABLED, the ninth condition is not met, and the NAV may be updated. If the ninth condition is not met, the STA or AP may update the NAV and perform Non-Primary Channel Access. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU, the ninth condition is met, and the NAV may not be updated if all other conditions are met. The ninth condition may be configured together with other conditions to form a single condition. For example, the ninth condition may be configured together with the sixth condition to form a single condition. The PPDU associated with the ninth condition may be any PPDU. The PPDU associated with the ninth condition may be any PPDU received from a STA or AP belonging to the same BSS as the ninth condition. The PPDU associated with the ninth condition may be any PPDU received from a STA or AP belonging to a different BSS (OBSS) from the ninth condition. The PPDU associated with the ninth condition may be the same PPDU as the 3rd condition and / or the 5th condition. The PPDU associated with the ninth condition may be a different PPDU from the 3rd condition and / or the 5th condition.

[0178] A STA or AP may not decide not to update its NAV based solely on the conditions of SRG OBSS PD level operation. In addition to the conditions of SRG OBSS PD level operation, a STA or AP may not update its NAV when all and / or any of the following conditions are met: - The STA has not received an information element related to Non-Primary Channel Access, or the STA that is an AP has not transmitted an information element related to Non-Primary Channel Access, - The RXVECTOR parameter NON_PRIMARY_CHANNLE_ACCESS (if present) of the received PPDU is set to NPCA_ENABLED.

[0179] In SRG OBSS PD level operation, the STA and / or AP may determine whether to update the NAV by considering information related to Non-Primary Channel Access. The information related to Non-Primary Channel Access may be an information element related to Non-Primary Channel Access. For example, the information element related to Non-Primary Channel Access may be an NPCA operation element, a UHR operation element, etc. In SRG OBSS PD level operation, when the PHY (physical layer) of the STA or AP issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA or AP may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, and fourth conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the received PPDU is an SRG PPDU, and the second condition is that the received signal strength level measured from the L-STF or L-LTF field of the PPDU, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (whichever is present and used to determine the PHY-CCA.indication) is below the SRG OBSS PD level.The third condition is that the (received) PPDU is not a non-HE PPDU carrying a frame whose RA field is equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. The fourth condition may be that the STA does not receive an information element related to Non-Primary Channel Access from its associated AP, or that the STA that is an AP does not transmit an information element related to Non-Primary Channel Access. In other words, if the STA receives an information element related to Non-Primary Channel Access from its associated AP, or if the STA that is an AP transmits an information element related to Non-Primary Channel Access, the fourth condition is not met, and the NAV may be updated. If the fourth condition is not met, the STA or AP may update the NAV and perform Non-Primary Channel Access. If the STA does not receive an information element related to Non-Primary Channel Access from an associated AP, or if the STA that is an AP does not transmit an information element related to Non-Primary Channel Access, the fourth condition is met, and if all other conditions are met, the NAV may not be updated. The fourth condition may be configured as a single condition together with the other conditions. For example, the fourth condition may be configured as a single condition together with the first condition.

[0180] In SRG OBSS PD level operation, the STA and / or AP may determine whether to update the NAV by considering information related to non-primary channel access. The information related to non-primary channel access may be an RXVECTOR parameter related to non-primary channel access. For example, the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS may be used. In SRG OBSS PD level operation, when the PHY (physical layer) of the STA or AP issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA or AP may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, and fourth conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the received PPDU is an SRG PPDU. The second condition is that the received signal strength level measured from the PPDU's L-STF or L-LTF field, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (if present and used to determine the PHY-CCA.indication) is below the SRG OBSS PD level. The third condition is that the (received) PPDU is not a non-HE PPDU carrying a frame with the RA field equal to the STA MAC address, a non-HE PPDU carrying a Public Action frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP.The fourth condition may be that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) is not set to NPCA_ENABLED. That is, the fourth condition may be that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_ENABLED, the fourth condition is not met and the NAV may be updated. If the fourth condition is not met, the STA or AP may update the NAV and perform Non Primary Channel Access. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS in the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or if the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU, the fourth condition is met and all other conditions are met, and the NAV may not be updated. The fourth condition may be configured together with other conditions as a single condition. For example, the fourth condition may be configured together with the first condition as a single condition. The PPDU related to the fourth condition may be any PPDU. The PPDU related to the fourth condition may be any PPDU received from a STA or AP belonging to the same BSS as the PPDU itself. The PPDU related to the fourth condition may be any PPDU received from a STA or AP belonging to a different BSS (OBSS) from the PPDU itself. The PPDU related to the fourth condition may be the same PPDU as the PPDU related to the first condition. The PPDU related to the fourth condition may be a different PPDU from the PPDU related to the first condition.

[0181] In the SRG OBSS PD level operation, the STA and / or AP may determine whether to update the NAV by taking into account information related to Non-Primary Channel Access. The information related to Non-Primary Channel Access may be an information element related to Non-Primary Channel Access and an RXVECTOR parameter related to Non-Primary Channel Access. For example, the information element related to Non-Primary Channel Access may be an NPCA operation element, a UHR operation element, etc. For example, the RXVECTOR parameter related to Non-Primary Channel Access may be the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS, etc. In SRG OBSS PD level operation, when the PHY (physical layer) of a STA or AP issues a PHY-RXEARLYSIG.indication or a PHY-RXSTART.indication following a PHY-CCA.indication(BUSY) upon receiving a PPDU, the MAC (MAC sublayer) of the STA or AP may issue a PHY-CCARESET.request primitive before the end of the PPDU without updating the NAV timer based on the PPDU if all of the first, second, third, fourth, and fifth conditions are met, or may treat the PPDU as not received for purposes of the NAV timer (without updating the NAV timer). The first condition is that the received PPDU is an SRG PPDU.The second condition is that the received signal strength level measured from the L-STF or L-LTF field, or the PHY SYNC field, shortSYNC field, or Long PHY SYNC field (if present and used to determine the PHY-CCA.indication) of the PPDU is below the SRG OBSS PD level. The third condition is that the (received) PPDU is not a non-HE PPDU carrying a frame with an RA field equal to the STA MAC address, a non-HE PPDU carrying a PublicAction frame, a non-HE PPDU carrying an NDP Announcement frame or a Fine Timing Measurement frame, or a non-HE NDP. The fourth condition may be that the STA has not received information elements related to Non-Primary Channel Access from its associated AP, or that the STA, which is an AP, has not transmitted information elements related to Non-Primary Channel Access. That is, if the STA receives an information element related to Non-Primary Channel Access from an associated AP, or if the STA that is an AP transmits an information element related to Non-Primary Channel Access, the fourth condition is not met, and the NAV may be updated. If the fourth condition is not met, the STA or AP may update the NAV and perform Non-Primary Channel Access. The fourth condition may be configured as a single condition in combination with other conditions. For example, the fourth condition may be configured as a single condition in combination with the first condition. A fifth condition may be that the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS (if present) is not set to NPCA_ENABLED.That is, the fifth condition may be satisfied when the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or when the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_ENABLED, the fifth condition is not met, and the NAV may be updated. If the fifth condition is not met, the STA or AP may update the NAV and perform Non-Primary Channel Access. If the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS of the received PPDU is set to NPCA_PROHIBIT or NPCA_DISABLED, or if the RXVECTOR parameter NON_PRIMARY_CHANNEL_ACCESS is not present in the received PPDU, the fifth condition is met, and the NAV may not be updated if all other conditions are met. The fifth condition may be configured together with other conditions to form a single condition. For example, the fifth condition may be configured together with the first condition to form a single condition. The PPDU related to the fifth condition may be any PPDU. The PPDU related to the fifth condition may be any PPDU received from a STA or AP belonging to the same BSS as the PPDU itself. The PPDU related to the fifth condition may be any PPDU received from a STA or AP belonging to a different BSS (OBSS) from the PPDU itself. The PPDU related to the fifth condition may be the same PPDU as the PPDU related to the first condition. The PPDU related to the fifth condition may be a different PPDU from the PPDU related to the first condition.

[0182] 14 is a diagram showing an example of processing related to a NAV update according to one aspect of this embodiment. The STA or AP receives a PPDU (S1401). The STA or AP determines whether multiple conditions related to a NAV update are met (S1402). If the STA or AP determines that multiple conditions related to a NAV update are not met (S1402: NO), the STA or AP performs a NAV update (S1403). If the STA or AP determines that multiple conditions related to a NAV update are met (S1402: YES), the STA or AP does not perform a NAV update (S1403).

[0183] As described above, in an embodiment of the present invention, a STA or an AP may use information related to Non-Primary Channel Access when determining whether to update a NAV. According to one aspect of the present invention, the STA and / or the AP determines information related to Non-Primary Channel Access as a condition for updating a NAV, and does not update the NAV if multiple conditions are met, and updates the NAV if even one of the multiple conditions is not met.

[0184] The programs operating in the base station device and terminal device according to the embodiments of the present invention may be programs (programs that cause a computer to function) that control a CPU (Central Processing Unit) or the like so as to realize the functions of the above-described embodiments of the present invention. Information handled by these devices is temporarily stored in RAM (Random Access Memory) during processing, and then stored in various ROMs such as Flash ROM (Read Only Memory) or HDD (Hard Disk Drive), and is read, modified, and written by the CPU as needed.

[0185] Note that the terminal device and part of the base station device in the above-described embodiments may be realized by a computer, in which case a program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by a computer system and executed.

[0186] The term "computer system" used here refers to a computer system built into a terminal device or base station device, and includes hardware such as an OS and peripheral devices. Also, the term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into a computer system.

[0187] Furthermore, the term "computer-readable recording medium" may include a medium that dynamically stores a program for a short period of time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, or a medium that stores a program for a certain period of time, such as a volatile memory within a computer system that serves as a server or client in such a case. The program may also be one that realizes part of the above-mentioned functions, or one that can realize the above-mentioned functions in combination with a program already recorded in the computer system.

[0188] The terminal device may comprise at least one processor and at least one memory containing computer program instructions (computer program). The memory and computer program instructions (computer program) may be configured to cause the terminal device to perform the operations and processes described in the above embodiments using the processor. The base station device may comprise at least one processor and at least one memory containing computer program instructions (computer program). The memory and computer program instructions (computer program) may be configured to cause the base station device to perform the operations and processes described in the above embodiments using the processor.

[0189] Furthermore, the base station device in the above-described embodiments can also be realized as a collection (device group) consisting of multiple devices. Each of the devices constituting the device group may have some or all of the functions or functional blocks of the base station device according to the above-described embodiments. The device group may have all of the functions or functional blocks of the base station device. Furthermore, the terminal devices according to the above-described embodiments can also communicate with the base station device as a collection.

[0190] Furthermore, some or all of the terminal device and base station device in the above-described embodiments may be realized as an LSI, which is typically an integrated circuit, or as a chipset. Each functional block of the terminal device and base station device may be individually formed into a chip, or some or all of them may be integrated into a chip. Furthermore, the integrated circuit method is not limited to LSI, and may be realized using a dedicated circuit or a general-purpose processor. Furthermore, if an integrated circuit technology that can replace LSI emerges due to advances in semiconductor technology, it is also possible to use an integrated circuit based on that technology.

[0191] Furthermore, in the above-described embodiment, a terminal device is described as an example of a communication device, but the present invention is not limited to this and can also be applied to terminal devices or communication devices such as stationary or non-movable electronic devices installed indoors or outdoors, for example, AV equipment, kitchen equipment, cleaning / washing equipment, air conditioning equipment, office equipment, vending machines, and other household appliances.

[0192] Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design modifications and the like are also included within the scope of the gist of the present invention. Furthermore, various modifications of one aspect of the present invention are possible within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, configurations in which elements described in the above embodiments are substituted with elements that achieve the same effect are also included.

[0193] One aspect of the present invention can be used, for example, in a communication system, a communication device (e.g., a mobile phone device, a base station device, a wireless LAN device, or a sensor device), an integrated circuit (e.g., a communication chip), or a program.

[0194] SU1, AU1 Antenna section SU2, AU2 RF section SU3, AU3 Physical layer processing section SU4, AU4 MAC layer processing section SU5 Upper layer packet processing section SU6, AU6 Radio transmission / reception section SU7, AU7 Frame processing section AU5 DSAF section

Claims

1. A terminal device comprising a receiving unit that receives a frame, the frame including a UHR operation element, a UHR STA controlled by the UHR operation element, the UHR operation element including a first field, the first field indicating whether NPCA is enabled, and if the first field indicates that NPCA is enabled, the terminal device may perform NPCA.

2. The terminal device of claim 1, wherein the NPCA switches from the primary channel to the NPCA primary channel when the primary channel is occupied by an OBSS.

3. The terminal device of claim 1, wherein the terminal device may transmit on one or more channels including the NPCA primary channel but excluding the primary channel, following a backoff procedure on the NPCA primary channel.

4. A base station device comprising a transmitting unit that transmits a frame, the frame including a UHR operation element, a UHR STA being controlled by the UHR operation element, the UHR operation element including a first field, the first field indicating whether NPCA is enabled, and if the first field indicates that NPCA is enabled, the base station device may perform NPCA.

5. The base station apparatus according to claim 4, wherein the NPCA switches from the primary channel to the NPCA primary channel when the primary channel is occupied by the OBSS.

6. The base station apparatus according to claim 4, wherein transmission may be performed on one or more channels that include the NPCA primary channel but do not include the primary channel, in accordance with a backoff procedure on the NPCA primary channel.

7. A communication method including a step of receiving a frame, the frame including a UHR operation element, a UHR STA being controlled by the UHR operation element, the UHR operation element including a first field, the first field indicating whether NPCA is enabled, and if the first field indicates that NPCA is enabled, the UHR STA may perform NPCA.

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