Method and apparatus for defining field including information related to CW value of NPCA primary channel and signaling field via management frame in wireless LAN system
By initializing the CW value of the NPCA primary channel differently through a management frame, the method optimizes channel access, reducing collisions and improving throughput in wireless LAN systems.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- LG ELECTRONICS INC
- Filing Date
- 2025-10-31
- Publication Date
- 2026-05-07
AI Technical Summary
Existing wireless LAN systems face challenges in optimizing channel access for non-primary channels, leading to increased collision probability and reduced throughput due to media access contention and traffic imbalance between primary and non-primary channels.
A method is proposed to signal through a management frame by defining a field containing information related to the CW value of an NPCA primary channel, allowing the CW value to be initialized differently from the BSS primary channel, thereby optimizing backoff procedures based on channel congestion and traffic load.
This approach reduces the probability of collisions and improves the utilization efficiency of the NPCA primary channel, ensuring fairness in media access and enhancing transmission delay and throughput performance.
Smart Images

Figure KR2025017723_07052026_PF_FP_ABST
Abstract
Description
Method and apparatus for signaling through a management frame by defining a field containing information related to the CW value of an NPCA primary channel in a wireless LAN system
[0001] The present specification relates to a technique for signaling through a management frame by defining a field containing information related to the CW value of an NPCA primary channel in a wireless LAN system, and more specifically, to a method and apparatus for configuring information used to initialize the CW value of an NPCA primary channel by assuming that the CW value of the NPCA primary channel is initialized to a value different from that of a BSS primary channel (existing primary channel).
[0002] Next-generation Wi-Fi (e.g., IEEE 802.11be and / or later) aims to support ultra-high reliability when transmitting signals to STAs, and to this end, various technologies are being considered to support high throughput, low latency, and extended range. For example, a procedure to access a non-primary channel can be performed.
[0003] The present specification proposes a method and apparatus for signaling through a management frame by defining a field containing information related to the CW value of an NPCA primary channel in a wireless LAN system.
[0004] One example of the present specification proposes a method of signaling through a management frame by defining a field containing information related to the CW value of an NPCA primary channel.
[0005] This embodiment can be performed in a network environment that supports a next-generation wireless LAN system (UHR (Ultra High Reliability) wireless LAN system or next wi-fi). The next-generation wireless LAN system is a wireless LAN system that improves upon the 802.11be system and can satisfy backward compatibility with the 802.11be system.
[0006] This embodiment is performed on an NPCA non-AP STA, and the NPCA non-AP STA may be a non-AP STA that supports NPCA operation. The NPCA AP may be an AP that supports NPCA operation. The NPCA non-AP STA and the NPCA AP may set the NPCA Supported field of the UHR MAC Capabilities Information field of the UHR Capabilities element to 1. The NPCA AP having an operating bandwidth smaller than 80 MHz cannot enable the NPCA operation.
[0007] This embodiment proposes a method of signaling through a management frame by defining a field containing information related to the CW value of the NPCA primary channel. Specifically, assuming that the CW value of the NPCA primary channel is initialized to a value different from that of the BSS primary channel (existing primary channel), a method of configuring information used to initialize the CW value of the NPCA primary channel is proposed.
[0008] An NPCA (Non-primary channel access) non-AP (non-access point) STA (station) receives a management frame from an NPCA AP.
[0009] The above NPCA non-AP STA performs backoff for the NPCA primary channel based on the above management frame.
[0010] The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field.
[0011] The above Initial NPCA QSRC field contains information about a first value used to initialize the first CW (Contention Window) parameter for the above NPCA primary channel.
[0012] The above first CW parameter is initialized based on the above first value and the CW minimum value for the BSS (Basic Service Set) primary channel.
[0013] That is, the present embodiment proposes a method for performing backoff for the NPCA primary channel by newly defining and signaling information related to the CW value of the NPCA primary channel, and selecting a backoff value within the minimum CW value that matches the NPCA primary channel state.
[0014] According to the method proposed in this embodiment, by newly defining and signaling information related to a CW value set by reflecting the congestion state or traffic load of the NPCA primary channel, the NPCA STA (NPCA non-AP STA or NPCA AP) can select a backoff value within a CW minimum value (CWmin) suitable for the state of the NPCA primary channel. Accordingly, the NPCA STA can perform a backoff procedure for the NPCA primary channel in a form optimized for the channel environment, and as a result, it has the effect of reducing the probability of collision due to media access contention and improving the utilization efficiency of the NPCA primary channel. In addition, by differentially adjusting the CW value according to the channel state, fairness in media access among NPCA STAs can be ensured, and traffic imbalance between the NPCA channel and the BSS primary channel can be mitigated, thereby improving the transmission delay and throughput performance of the entire BSS.
[0015] FIG. 1 shows an example of a transmitting device and / or receiving device of the present specification.
[0016] Figure 2 is a conceptual diagram showing the structure of a wireless LAN (WLAN).
[0017] Figure 3 is a diagram illustrating a general link setup process.
[0018] FIG. 4 illustrates an example of a multi-link (ML).
[0019] FIG. 5 illustrates a PPDU (physical protocol data unit or physical layer (PHY) protocol data unit) transmitted / received in an STA of the present specification.
[0020] Figure 6 is a diagram showing the arrangement of resource units (RU) used for a 20 MHz PPDU.
[0021] Figure 7 is a diagram showing the arrangement of resource units (RU) used for a 40 MHz PPDU.
[0022] Figure 8 is a diagram showing the arrangement of resource units (RU) used for an 80 MHz PPDU.
[0023] Figure 9 shows the operation according to UL-MU.
[0024] Figure 10 shows an example of a channel used / supported / defined within the 2.4 GHz band.
[0025] FIG. 11 illustrates an example of a channel used / supported / defined within the 5 GHz band.
[0026] FIG. 12 illustrates an example of a channel used / supported / defined within the 6 GHz band.
[0027] Figure 13 shows an example of a MAC frame header.
[0028] FIG. 14 shows a modified example of a transmitting device and / or receiving device of the present specification.
[0029] FIG. 15 illustrates an example of channel access in an 802.11 wireless LAN system.
[0030] Figure 16 illustrates an example of the basic procedure of SCA.
[0031] FIG. 17 illustrates an example of the EDCA Parameter Set element format of an 802.11 wireless LAN system.
[0032] FIG. 18 illustrates an example of Option 1, which maintains the CW value of SCH when switching to SCH.
[0033] FIG. 19 illustrates an example of Option 2, which initializes the CW value of SCH to CWmin when switching to SCH.
[0034] FIG. 20 illustrates an example of Option 1, which maintains the BC value of SCH when switching to SCH.
[0035] FIG. 21 illustrates an example of Option 2, which sets a new BC value of SCH when switching to SCH.
[0036] Figure 22 illustrates the basic Secondary Channel Access operation process of an STA.
[0037] FIG. 23 is a flowchart illustrating the operation of a transmitting device according to the present embodiment.
[0038] FIG. 24 is a flowchart illustrating the operation of a receiving device according to the present embodiment.
[0039] FIG. 25 is a flowchart illustrating a procedure in which an NPCA AP according to the present embodiment transmits information to initialize the CW value of an NPCA primary channel through a management frame.
[0040] FIG. 26 is a flowchart illustrating a procedure for an NPCA non-AP STA according to the present embodiment to receive information through a management frame for initializing the CW value of an NPCA primary channel.
[0041] In this specification, “A or B” may mean “only A,” “only B,” or “both A and B.” Alternatively, in this specification, “A or B” may be interpreted as “A and / or B.” For example, in this specification, “A, B or C” may mean “only A,” “only B,” “only C,” or “any combination of A, B and C.”
[0042] As used herein, a slash ( / ) or a comma may mean “and / or.” For example, “A / B” may mean “and / or B.” Accordingly, “A / B” may mean “only A,” “only B,” or “both A and B.” For example, “A, B, C” may mean “A, B, or C.”
[0043] In this specification, “at least one of A and B” may mean “only A,” “only B,” or “both A and B.” Additionally, in this specification, the expressions “at least one of A or B” or “at least one of A and / or B” may be interpreted as synonymous with “at least one of A and B.”
[0044] Additionally, parentheses used in this specification may mean “for example.” Specifically, when indicated as “control information (UHR-Signal field),” the “UHR-Signal field” may be proposed as an example of “control information.” In other words, the “control information” of this specification is not limited to the “UHR-Signal field,” and the “UHR-Signal field” may be proposed as an example of “control information.” Furthermore, even when indicated as “control information (UHR-Signal field),” the “UHR-Signal field” may be proposed as an example of “control information.”
[0045] Additionally, as used herein, “a / an” may mean “at least one” or “one or more.” Also, terms ending in “(s)” may mean “at least one” or “one or more.”
[0046] Additionally, the expressions “based on,” “on the basis of,” or “according to” as used herein mean “based at least in part on,” and do not mean “based only on one.”
[0047] Technical features described individually within a single drawing in this specification may be implemented individually or simultaneously.
[0048] The following examples of this specification may be applied to various wireless communication systems. For example, the following examples of this specification may be applied to wireless local area network (WLAN) systems. For example, this specification may be applied to IEEE 802.11a / g / n / ac / ax / be / bn standards. In addition, the examples of this specification may be applied to Ultra High Reliability (UHR) standards or next-generation wireless LAN standards that enhance IEEE 802.11bn. In addition, the examples of this specification may be applied to mobile communication systems. For example, they may be applied to mobile communication systems based on Long Term Evolution (LTE) and its evolution based on 3GPP (3rd Generation Partnership Project) standards.
[0049] To explain the technical features of this specification, the technical features to which this specification can be applied are described below.
[0050] FIG. 1 shows an example of a transmitting device and / or receiving device of the present specification.
[0051] An example of FIG. 1 can perform various technical features described below. FIG. 1 relates to at least one STA (station). For example, the STA (110, 120) of this specification may also be referred to by various names such as mobile terminal, wireless device, Wireless Transmit / Receive Unit (WTRU), User Equipment (UE), Mobile Station (MS), Mobile Subscriber Unit, or simply user. The STA (110, 120) of this specification may also be referred to by various names such as network, base station, Node-B, Access Point (AP), repeater, router, relay, etc. The STA (110, 120) of this specification may also be referred to by various names such as receiving apparatus, transmitting device, receiving STA, transmitting STA, receiving device, transmitting device, etc.
[0052] For example, the STA (110, 120) can perform the role of an access point (AP) or a non-AP. That is, the STA (110, 120) of this specification can perform the functions of an AP and / or a non-AP. In this specification, an AP may also be indicated as an AP STA.
[0053] The STA (110, 120) of this specification may support various communication standards other than the IEEE 802.11 standard. For example, it may support communication standards according to 3GPP standards (e.g., LTE, LTE-A, 5G NR standards). In addition, the STA of this specification may be implemented in various devices such as mobile phones, vehicles, and personal computers. Furthermore, the STA of this specification may support communication for various communication services such as voice calls, video calls, data communication, and self-driving.
[0054] In this specification, the STA (110, 120) may include a medium access control (MAC) that complies with the provisions of the IEEE 802.11 standard and a physical layer interface for the wireless medium.
[0055] Based on side drawing (a) of Fig. 1, STA (110, 120) is described as follows.
[0056] The first STA (110) may include a processor (111), memory (112), and a transceiver (113). The illustrated processor, memory, and transceiver may each be implemented as separate chips, or at least two blocks / functions may be implemented through a single chip.
[0057] The transceiver (113) of the first STA performs the operation of transmitting and receiving signals. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).
[0058] For example, the first STA (110) can perform the intended operation of the AP. For example, the processor (111) of the AP can receive a signal through the transceiver (113), process the received signal, generate a transmitted signal, and perform control for transmitting the signal. The memory (112) of the AP can store the signal received through the transceiver (113) (i.e., the received signal) and the signal to be transmitted through the transceiver (i.e., the transmitted signal).
[0059] For example, the second STA (120) can perform the intended operation of a Non-AP STA. For example, the non-AP transceiver (123) performs the operation of transmitting and receiving signals. Specifically, it can transmit and receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).
[0060] For example, the processor (121) of the Non-AP STA can receive a signal through the transceiver (123), process the received signal, generate a transmitted signal, and perform control for transmitting the signal. The memory (122) of the Non-AP STA can store the signal received through the transceiver (123) (i.e., the received signal) and can store the signal to be transmitted through the transceiver (i.e., the transmitted signal).
[0061] For example, the operation of the device indicated as AP in the following specification may be performed in the first STA (110) or the second STA (120). For example, if the first STA (110) is the AP, the operation of the device indicated as AP is controlled by the processor (111) of the first STA (110), and related signals may be transmitted or received through a transceiver (113) controlled by the processor (111) of the first STA (110). Additionally, control information related to the operation of the AP or the transmission / reception signals of the AP may be stored in the memory (112) of the first STA (110). Additionally, if the second STA (110) is the AP, the operation of the device indicated as AP is controlled by the processor (121) of the second STA (120), and related signals may be transmitted or received through a transceiver (123) controlled by the processor (121) of the second STA (120). In addition, control information related to the operation of the AP or the transmission / reception signals of the AP can be stored in the memory (122) of the second STA (110).
[0062] For example, the operation of a device indicated as non-AP (or User-STA) in the following specification may be performed in the STA (110) or the second STA (120). For example, if the second STA (120) is non-AP, the operation of the device indicated as non-AP is controlled by the processor (121) of the second STA (120), and related signals may be transmitted or received through a transceiver (123) controlled by the processor (121) of the second STA (120). Additionally, control information related to the operation of the non-AP or the transmission / reception signals of the AP may be stored in the memory (122) of the second STA (120). For example, if the first STA (110) is a non-AP, the operation of the device marked as non-AP is controlled by the processor (111) of the first STA (110), and the related signal can be transmitted or received through a transceiver (113) controlled by the processor (111) of the first STA (120). Additionally, control information related to the operation of the non-AP or the transmission / reception signal of the AP can be stored in the memory (112) of the first STA (110).
[0063] In the following specification, a device referred to as (transmission / reception) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmission / reception) Terminal, (transmission / reception) device, (transmission / reception) apparatus, network, etc. may refer to the STA (110, 120) of FIG. 1. For example, a device indicated without specific drawing symbols as (transmission / reception) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmission / reception) Terminal, (transmission / reception) device, (transmission / reception) apparatus, network, etc. may also refer to the STA (110, 120) of FIG. 1. For example, in the following example, the operation of various STAs transmitting and receiving signals (e.g., PPDU) may be performed by the transceivers (113, 123) of FIG. 1. Additionally, in the following example, the operation of various STAs generating transmission and reception signals or performing data processing or calculations in advance for transmission and reception signals may be performed by the processors (111, 121) of FIG. 1.For example, an example of an operation to generate a transmission / reception signal or to perform data processing or operations in advance for a transmission / reception signal may include: 1) an operation to determine / acquire / configure / operate / decode / encode bit information of sub-fields (SIG, STF, LTF, Data) included in the PPDU; 2) an operation to determine / configure / acquire time resources or frequency resources (e.g., subcarrier resources) used for sub-fields (SIG, STF, LTF, Data) included in the PPDU; 3) an operation to determine / configure / acquire specific sequences (e.g., pilot sequence, STF / LTF sequence, extra sequence applied to SIG) used for sub-fields (SIG, STF, LTF, Data) included in the PPDU; 4) a power control operation and / or power saving operation applied to the STA; and 5) an operation related to determining / acquiring / configuring / operating / decoding / encoding, etc. of an ACK signal. In addition, in the following example, various information (e.g., information related to fields, subfields, control fields, parameters, power, etc.) used by various STAs for determining / acquiring / configuring / calculating / decoding / encoding of transmission and reception signals can be stored in the memory (112, 122) of FIG. 1.
[0064] The device / STA of the aforementioned supplementary drawing (a) of FIG. 1 can be modified as shown in supplementary drawing (b) of FIG. 1. Hereinafter, the STA (110, 120) of this specification will be described based on supplementary drawing (b) of FIG. 1.
[0065] For example, the transceiver (113, 123) shown in side drawing (b) of FIG. 1 can perform the same function as the transceiver shown in side drawing (a) of FIG. 1 described above. For example, the processing chip (114, 124) shown in side drawing (b) of FIG. 1 may include a processor (111, 121) and a memory (112, 122). The processor (111, 121) and the memory (112, 122) shown in side drawing (b) of FIG. 1 can perform the same function as the processor (111, 121) and the memory (112, 122) shown in side drawing (a) of FIG. 1 described above.
[0066] The mobile terminal, wireless device, Wireless Transmit / Receive Unit (WTRU), User Equipment (UE), Mobile Station (MS), Mobile Subscriber Unit, user, User STA, network, Base Station, Node-B, AP (Access Point), repeater, router, relay, receiving device, transmitting device, receiving STA, transmitting STA, receiving Device, transmitting Device, receiving Apparatus, and / or transmitting Apparatus described below may refer to the STA (110, 120) shown in side drawings (a) / (b) of FIG. 1, or the processing chip (114, 124) shown in side drawing (b) of FIG. 1. That is, the technical features of the present specification may be performed in the STA (110, 120) shown in side drawings (a) / (b) of FIG. 1, or only in the processing chip (114, 124) shown in side drawing (b) of FIG. 1. For example, the technical feature of the transmitting STA transmitting a control signal may be understood as a technical feature in which a control signal generated in the processor (111, 121) shown in side drawings (a) / (b) of FIG. 1 is transmitted through the transceiver (113, 123) shown in side drawings (a) / (b) of FIG. 1. Alternatively, the technical feature of the transmitting STA transmitting a control signal may be understood as a technical feature in which a control signal to be transmitted from the processing chip (114, 124) shown in side drawing (b) of FIG. 1 is generated to the transceiver (113, 123).
[0067] For example, the technical feature of the receiving STA receiving a control signal can be understood as the technical feature of the control signal being received by the transceiver (113, 123) shown in side view (a) of FIG. 1. Alternatively, the technical feature of the receiving STA receiving a control signal can be understood as the technical feature of the control signal received by the transceiver (113, 123) shown in side view (a) of FIG. 1 being acquired by the processor (111, 121) shown in side view (a) of FIG. 1. Alternatively, the technical feature of the receiving STA receiving a control signal can be understood as the technical feature of the control signal received by the transceiver (113, 123) shown in side view (b) of FIG. 1 being acquired by the processing chip (114, 124) shown in side view (b) of FIG. 1.
[0068] Referring to side view (b) of FIG. 1, software code (115, 125) may be included in memory (112, 122). The software code (115, 125) may include instructions that control the operation of the processor (111, 121). The software code (115, 125) may be included in various programming languages.
[0069] The processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may include an application-specific integrated circuit (ASIC), other chipsets, logic circuits, and / or data processing devices. The processor may be an application processor (AP). For example, the processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modem (modulator and demodulator). For example, the processor (111, 121) or processing chip (114, 124) illustrated in FIG. 1 may be a SNAPDRAGON™ series processor manufactured by Qualcomm®, an EXYNOSTM series processor manufactured by Samsung®, an A series processor manufactured by Apple®, a HELIO™ series processor manufactured by MediaTek®, an ATOM™ series processor manufactured by INTEL®, or a processor enhanced therefrom.
[0070] In this specification, an uplink may refer to a link for communication from a non-AP STA to an AP STA, and uplink PPDUs / packets / signals, etc. may be transmitted through the uplink. Additionally, in this specification, a downlink may refer to a link for communication from an AP STA to a non-AP STA, and downlink PPDUs / packets / signals, etc. may be transmitted through the downlink.
[0071] Figure 2 is a conceptual diagram showing the structure of a wireless LAN (WLAN).
[0072] The top of Figure 2 shows the structure of the IEEE (Institute of Electrical and Electronic Engineers) 802.11 infrastructure BSS (basic service set).
[0073] The top of Figure 2 shows the structure of the IEEE (Institute of Electrical and Electronic Engineers) 802.11 infrastructure BSS (basic service set).
[0074] Referring to the top of FIG. 2, the wireless LAN system may include one or more infrastructure BSSs (200, 205) (hereinafter BSS). The BSS (200, 205) is a set of APs and STAs, such as an AP (access point, 225) and STA1 (Station, 200-1), that can communicate with each other by successfully synchronizing, and is not a concept referring to a specific area. The BSS (205) may include one or more STAs (205-1, 205-2) that can be combined with one AP (230).
[0075] The BSS may include at least one STA, an AP (225, 230) that provides a distribution service, and a distribution system (DS, 210) that connects multiple APs.
[0076] A distributed system (210) can implement an extended service set (ESS, 240) by connecting multiple BSSs (200, 205). The term ESS (240) may be used to refer to a network formed by connecting one or more APs through the distributed system (210). APs included in a single ESS (240) may have the same service set identification (SSID).
[0077] The portal (portal, 220) can act as a bridge to connect a wireless LAN network (IEEE 802.11) with another network (e.g., 802.X).
[0078] In a BSS like the one at the top of Fig. 2, a network between APs (225, 230) and a network between APs (225, 230) and STAs (200-1, 205-1, 205-2) can be implemented. However, it may also be possible to establish a network between STAs and perform communication without APs (225, 230). A network that establishes a network between STAs and performs communication without APs (225, 230) is defined as an ad-hoc network or an independent basic service set (IBSS).
[0079] The bottom of Fig. 2 is a conceptual diagram showing IBSS.
[0080] Referring to the bottom of Fig. 2, the IBSS is a BSS that operates in ad-hoc mode. Since the IBSS does not include an AP, there is no centralized management entity that performs management functions centrally. That is, in the IBSS, the STAs (250-1, 250-2, 250-3, 255-4, 255-5) are managed in a distributed manner. In the IBSS, all STAs (250-1, 250-2, 250-3, 255-4, 255-5) can be mobile STAs, and since access to the distributed system is not allowed, they form a self-contained network.
[0081] Figure 3 is a diagram illustrating a general link setup process.
[0082] In the described S310 step, the STA can perform a network discovery operation. The network discovery operation may include the STA's scanning operation. That is, in order for the STA to access a network, it must find a network it can join. Before joining a wireless network, the STA must identify a compatible network, and the process of identifying networks existing in a specific area is called scanning. Scanning methods include active scanning and passive scanning.
[0083] Figure 3 illustrates a network discovery operation that includes an active scanning process as an example. In active scanning, the STA performing the scanning moves between channels and transmits a probe request frame to search for nearby APs, and waits for a response. The responder transmits a probe response frame as a response to the probe request frame to the STA that transmitted the probe request frame. Here, the responder may be the STA that last transmitted a beacon frame from the BSS of the channel being scanned. In a BSS, the AP becomes the responder because it transmits the beacon frame, whereas in an IBSS, the responder is not constant because STAs within the IBSS take turns transmitting the beacon frame. For example, an STA that transmits a probe request frame on channel 1 and receives a probe response frame on channel 1 can store BSS-related information included in the received probe response frame and move to the next channel (e.g., channel 2) to perform scanning in the same way (i.e., transmit and receive probe request / response on channel 2).
[0084] Although not shown in the example of Fig. 3, scanning operations may also be performed using a passive scanning method. An STA performing scanning based on passive scanning can wait for a beacon frame while switching between channels. A beacon frame is one of the management frames in IEEE 802.11, which announces the presence of a wireless network and is periodically transmitted to allow a scanning STA to find the wireless network and join it. In a BSS, the AP performs the role of periodically transmitting beacon frames, while in an IBSS, STAs within the IBSS take turns transmitting beacon frames. When a scanning STA receives a beacon frame, it stores the information about the BSS included in the beacon frame and records the beacon frame information in each channel while moving to another channel. An STA that has received a beacon frame can store the BSS-related information included in the received beacon frame, move to the next channel, and perform scanning in the next channel in the same manner.
[0085] The STA that discovered the network can perform an authentication process through step S320. This authentication process may be referred to as the first authentication process to clearly distinguish it from the security setup operation of step S340 described later. The authentication process of S320 may include the STA sending an authentication request frame to the AP, and the AP sending an authentication response frame to the STA in response. The authentication frame used in the authentication request / response corresponds to a management frame.
[0086] The authentication frame may include information regarding the authentication algorithm number, authentication transaction sequence number, status code, challenge text, RSN (Robust Security Network), Finite Cyclic Group, etc.
[0087] The STA can send an authentication request frame to the AP. Based on the information contained in the received authentication request frame, the AP can determine whether to allow authentication for the STA. The AP can provide the result of the authentication process to the STA through an authentication response frame.
[0088] A successfully authenticated STA may perform an association process based on step S330. The association process includes the STA sending an association request frame to the AP, and in response, the AP sending an association response frame to the STA. For example, the association request frame may include information regarding various capabilities, beacon listen interval, service set identifier (SSID), supported rates, supported channels, RSN, mobility domain, supported operating classes, Traffic Indication Map Broadcast request, interworking service capabilities, etc. For example, a connection response frame may include information related to various capabilities, status code, AID (Association ID), support rate, EDCA (Enhanced Distributed Channel Access) parameter set, RCPI (Received Channel Power Indicator), RSNI (Received Signal to Noise Indicator), mobility domain, timeout interval (association comeback time), overlapping BSS scan parameters, TIM broadcast response, QoS map, etc.
[0089] Subsequently, in step S340, the STA may perform a security setup process. The security setup process of step S340 may include, for example, a process of setting up a private key through a 4-way handshake via an EAPOL (Extensible Authentication Protocol over LAN) frame.
[0090] FIG. 4 illustrates an example of a multi-link (ML).
[0091] As illustrated in FIG. 4, multiple multi-link devices (MLDs) can communicate through a multi-link. The MLDs can be classified into an AP MLD containing multiple AP STAs and a non-AP MLD containing multiple non-AP STAs. That is, the AP MLD may include affiliated APs (i.e., AP STAs), and the non-AP MLD may include affiliated STAs (i.e., non-AP STAs, or user-STAs).
[0092] A multilink may include a first link and a second link, and different channels / subchannels / frequency resources may be assigned to the first and second links. The first and second multilinks may be identified by a link ID of 4 bits (or other n bits). The first and second links may be configured in the same 2.4 GHz, 5 GHz, or 6 GHz band. Alternatively, the first link and the link may be configured in different bands.
[0093] The AP MLD of FIG. 4 includes three affiliated APs. In one example of FIG. 4, AP1 may operate in the 2.4 GHz band, AP2 may operate in the 5 GHz band, and AP3 may operate in the 6 GHz band. In one example of FIG. 4, the first link in which AP1 and non-AP1 operate may be defined as a channel / subchannel / frequency resource within the 2.4 GHz band. Additionally, in one example of FIG. 4, the second link in which AP2 and non-AP2 operate may be defined as a channel / subchannel / frequency resource within the 5 GHz band. Additionally, in one example of FIG. 4, the third link in which AP3 and non-AP3 operate may be defined as a channel / subchannel / frequency resource within the 6 GHz band.
[0094] In one example of FIG. 4, AP1 can initiate a multilink setup procedure (ML setup procedure) by transmitting an Association Request frame to non-AP STA1. In one example of FIG. 4, non-AP STA1 can transmit an Association Response frame in response to the Association Request frame. Each AP (e.g., AP1 / 2 / 3) shown in FIG. 4 may be the same as the AP shown in FIG. 1 and / or FIG. 2, and each non-AP (e.g., non-AP1 / 2 / 3) shown in FIG. 4 may be the same as the STA shown in FIG. 1 and / or FIG. 2 (i.e., user-STA or non-AP STA).
[0095] The specific features of this specification are not limited to the specific features of FIG. 4. That is, the number of links can be defined in various ways, and multiple links can be defined in various ways within at least one band.
[0096] FIG. 5 illustrates a PPDU (physical protocol data unit or physical layer (PHY) protocol data unit) transmitted / received in an STA of the present specification.
[0097] The STAs of this specification (e.g., AP STA, non-AP STA, AP MLD, non-AP MLD) can transmit and / or receive the PPDU of FIG. 5. The PPDU described in this specification may have the structure of FIG. 5, for example. Additionally, the PPDU described in this specification, the Ultra High Reliability (UHR) PPDU, may be referred to by various names such as transmit PPDU, receive PPDU, first type or N type PPDU. The PPDU described in this specification may be used in WLAN systems defined according to IEEE 802.11bn and / or next-generation WLAN systems that improve upon IEEE 802.11bn.
[0098] The PPDU of FIG. 5 may be related to various PPDU types used in a UHR system. For example, the example of FIG. 5 may be used for at least one of SU (single-user) mode / type / transmission, MU (multi-user) mode / type / transmission, and NDP (null data packet) mode / type / transmission related to channel sounding. For example, if the example of FIG. 5 is related to NDP, the illustrated Data field may be omitted. If the PPDU of FIG. 5 is used for TB (Trigger-based) mode, the UHR-SIG of FIG. 5 may be omitted. In other words, an STA that receives a Trigger frame for UL-MU (Uplink-MU) communication may transmit a PPDU in which the UHR-SIG is omitted in the example of FIG. 5.
[0099] In FIG. 5, L-STF to UHR-LTF can be called a preamble or physical preamble and can be generated / transmitted / received / acquired / decoded at the physical layer (included in the transmitting / receiving STA).
[0100] Each block illustrated in FIG. 5 may be referred to as a field / subfield / signal, etc. As illustrated in FIG. 5, the names of these fields / subfields / signals may be L-STF (legacy short training field), L-LTF (legacy long training field), L-SIG (legacy signal), RL-SIG (repeated L-SIG), U-SIG (Universal Signal), UHR-SIG (UHR-signal), etc.
[0101] The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields in Fig. 5 can be set to 312.5 kHz, and the subcarrier spacing of the UHR-STF, UHR-LTF, and Data fields can be set to 78.125 kHz. That is, the tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields can be displayed in units of 312.5 kHz, and the tone index (or subcarrier index) of the UHR-STF, UHR-LTF, and Data fields can be displayed in units of 78.125 kHz.
[0102] The PPDU of Fig. 5, L-LTF and L-STF, may be the same as conventional fields (e.g., non-HT LTF and non-HT STF defined in conventional WLAN standards).
[0103] The L-SIG field of FIG. 5 may contain, for example, 24 bits of bit information. For example, the 24 bits of information may include a 4-bit Rate field, a 1-bit Reserved bit, a 12-bit Length field, a 1-bit Parity bit, and a 6-bit Tail bit. For example, the 12-bit Length field may contain information regarding the length or time duration of the PPDU. For example, the value of the 12-bit Length field may be determined based on the type of the PPDU. For example, if the PPDU is a non-HT (non-High Throughput), HT (High Throughput), VHT (Very High Throughput) PPDU, or an EHT (extremely high throughput) PPDU, or a UHR PPDU, the value of the Length field may be determined as a multiple of 3. For example, if the PPDU is an HE PPDU, the value of the Length field may be determined as "a multiple of 3 + 1" or "a multiple of 3 + 2". In other words, for non-HT, HT, VHT PPDU, or EHT PPDU, UHR PPDU, the value of the Length field can be determined as a multiple of 3, and for HE (High-Efficiency) PPDU, the value of the Length field can be determined as "a multiple of 3 + 1" or "a multiple of 3 + 2". In other words, the Length field in a UHR PPDU is set to a value satisfying the condition that the remainder is zero when LENGTH is divided by 3.
[0104] For example, a (non-AP and AP) STA can apply BCC encoding based on a code rate of 1 / 2 to 24 bits of information in the L-SIG field. Subsequently, the transmitting STA can obtain 48 bits of BCC encoding. BPSK modulation can be applied to the 48 bits of encoding to generate 48 BPSK symbols. The transmitting STA can map the 48 BPSK symbols to positions excluding the pilot subcarrier {subcarrier indices -21, -7, +7, +21} and the DC subcarrier {subcarrier index 0}. Consequently, the 48 BPSK symbols can be mapped to subcarrier indices -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. The transmitting STA can additionally map the signal of {-1, -1, -1, 1} to the subcarrier index {-28, -27, +27, +28}. The above signal can be used for channel estimation for the frequency domain corresponding to {-28, -27, +27, +28}.
[0105] For example, the (non-AP and AP) STA can generate an RL-SIG that is identical to the L-SIG. BPSK modulation may be applied to the RL-SIG. The receiving (non-AP and AP) STA can determine that the received PPDU is a HE PPDU, EHT PPDU, or UHR PPDU based on the presence of the RL-SIG. In other words, the receiving (non-AP and AP) STA can determine that the received PPDU is one of the HE PPDU, EHT PPDU, or UHR PPDU if the RL-SIG is present. In other words, the receiving (non-AP and AP) STA can determine that the received PPDU is one of the non-HT PPDU, HT PPDU, or VHT PPDU if the RL-SIG is not present. In other words, the RL-SIG field is a repeat of the L-SIG field and is used to differentiate an UHR PPDU from a non-HT PPDU, HT PPDU, and VHT PPDU.
[0106] After the RL-SIG in Fig. 5, a U-SIG (Universal SIG) may be inserted. The U-SIG may be referred to by various names such as the first SIG field, first SIG, first type SIG, control signal, control signal field, first (type) control signal, common control field, and common control signal.
[0107] U-SIG may contain N bits of information and may contain information to identify the type of EHT PPDU. For example, U-SIG may be constructed based on two symbols (e.g., two consecutive OFDM symbols). Each symbol for U-SIG (e.g., OFDM symbol) may have a duration of 4 us. Each symbol of U-SIG may be used to transmit 26 bits of information. For example, each symbol of U-SIG may be transmitted and received based on 52 data tones and 4 pilot tones.
[0108] For example, A bit information (e.g., 52 un-coded bits) can be transmitted through U-SIG, and the first symbol of U-SIG can transmit the first X bit information (e.g., 26 un-coded bits) of the total A bit information, and the second symbol of U-SIG can transmit the remaining Y bit information (e.g., 26 un-coded bits) of the total A bit information. For example, the transmitting STA can obtain the 26 un-coded bits included in each U-SIG symbol. The transmitting STA can generate 52-coded bits by performing convolutional encoding (i.e., BCC encoding) based on a rate of R=1 / 2 and can perform interleaving on the 52-coded bits. The transmitting STA can generate 52 BPSK symbols assigned to each U-SIG symbol by performing BPSK modulation on the interleaved 52-coded bits. A single U-SIG symbol can be transmitted based on 56 tones (subcarriers) from subcarrier index -28 to subcarrier index +28, excluding DC index 0. 52 BPSK symbols generated by the transmitting STA can be transmitted based on the remaining tones (subcarriers), excluding the pilot tones -21, -7, +7, and +21.
[0109] For example, A bit information (e.g., 52 un-coded bits) transmitted by U-SIG may include a CRC field (e.g., a field of 4 bits) and a tail field (e.g., a field of 6 bits). The CRC field and the tail field may be transmitted through a second symbol of U-SIG. The CRC field may be generated based on 26 bits assigned to the first symbol of U-SIG and the remaining 16 bits within the second symbol excluding the CRC / tail field, and may be generated based on a conventional CRC calculation algorithm. Additionally, the tail field may be used to terminate the trellis of a convolutional decoder and may be set, for example, to "000000".
[0110] A bit information (e.g., 52 un-coded bits) transmitted by U-SIG (or U-SIG field) can be divided into version-independent bits and version-dependent bits. For example, the size of the version-independent bits can be fixed or variable. For example, the version-independent bits may be assigned only to the first symbol of U-SIG, or the version-independent bits may be assigned to both the first and second symbols of U-SIG. For example, the version-independent bits and the version-dependent bits may be referred to by various names, such as the first control bit and the second control bit.
[0111] For example, the version-independent bits of U-SIG may include a 3-bit PHY version identifier. For example, the 3-bit PHY version identifier may include information related to the PHY version of the transmitted and received PPDU. For example, a first value of the 3-bit PHY version identifier (e.g., a value of 000) may indicate that the transmitted and received PPDU is an EHT PPDU. Additionally, a second value of the 3-bit PHY version identifier (e.g., a value of 001) may indicate that the transmitted and received PPDU is a UHR PPDU.
[0112] In other words, when an (AP / non-AP) STA transmits an EHT PPDU, it can set a 3-bit PHY version identifier to a first value. In other words, a receiving (AP / non-AP) STA can determine that the received PPDU is an EHT PPDU based on the PHY version identifier having the first value, and can determine that the received PPDU is a UHR PPDU based on the PHY version identifier having the second value.
[0113] For example, the version-independent bits of U-SIG may include a 1-bit UL / DL flag field. The first value of the 1-bit UL / DL flag field is related to UL communication, and the second value of the UL / DL flag field is related to DL communication.
[0114] For example, the version-independent bits of U-SIG may include information regarding the length of the TXOP (transmission opportunity) and information regarding the BSS color ID.
[0115] For example, if the UHR PPDU is classified into various types (e.g., type related to SU transmission (performed based on UL or DL), type related to DL transmission, type related to NDP transmission, type related to DL non-MU-MIMO, type related to DL MU-MIMO, type related to Multi-AP operation, type related to CBF (Coordinated beamforming) and SR (Spatial Reuse), type related to C-OFDMA (Coordinated OFDMA), type related to C-TDMA (Coordinated TDMA)), information regarding the type of the EHT PPDU (e.g., 2-bit or 3-bit information) may be included in the version-dependent bits of the U-SIG.
[0116] For example, U-SIG may include: 1) a bandwidth field containing information regarding bandwidth; 2) a field containing information regarding the MCS technique applied to UHR-SIG; 3) an indication field containing information regarding whether the dual subcarrier modulation (DCM) technique is applied to UHR-SIG; 4) a field containing information regarding the number of symbols used for UHR-SIG; 5) a field containing information regarding whether UHR-SIG is generated across the entire band; 6) a field containing information regarding the type of UHR-LTF / STF; and 7) information regarding a field indicating the length of UHR-LTF and CP length.
[0117] Preamble puncturing may be applied to the PPDU of Fig. 5. Preamble puncturing means applying puncturing to a portion of the total band of the PPDU (e.g., a secondary 20 MHz band). For example, when an 80 MHz PPDU is transmitted, the STA applies puncturing to the secondary 20 MHz band within the 80 MHz band and can transmit the PPDU only through the primary 20 MHz band and the secondary 40 MHz band.
[0118] For example, the pattern of preamble puncturing can be pre-set. For example, when a first puncturing pattern is applied, puncturing may be applied only to a secondary 20 MHz band within an 80 MHz band. For example, when a second puncturing pattern is applied, puncturing may be applied only to one of two secondary 20 MHz bands included in a secondary 40 MHz band within an 80 MHz band. For example, when a third puncturing pattern is applied, puncturing may be applied only to a secondary 20 MHz band included in a primary 80 MHz band within a 160 MHz band (or 80+80 MHz band). For example, when the fourth puncturing pattern is applied, within the 160 MHz band (or 80+80 MHz band), the primary 40 MHz band included in the primary 80 MHz band is present, and puncturing may be applied to at least one 20 MHz channel that does not belong to the primary 40 MHz band.
[0119] Information regarding preamble puncturing applied to the PPDU may be included in the U-SIG and / or UHR-SIG. For example, the first field of the U-SIG may include information regarding the contiguous bandwidth of the PPDU, and the second field of the U-SIG may include information regarding preamble puncturing applied to the PPDU.
[0120] For example, U-SIG and UHR-SIG may include information regarding preamble puncturing based on the following method. If the bandwidth of the PPDU exceeds 80 MHz, the U-SIG may be configured individually in 80 MHz units. For example, if the bandwidth of the PPDU is 160 MHz, the PPDU may include a first U-SIG for the first 80 MHz band and a second U-SIG for the second 80 MHz band. In this case, the first field of the first U-SIG may include information regarding the 160 MHz bandwidth, and the second field of the first U-SIG may include information regarding preamble puncturing applied to the first 80 MHz band (i.e., information regarding the preamble puncturing pattern). Additionally, the first field of the second U-SIG may include information regarding a 160 MHz bandwidth, and the second field of the second U-SIG may include information regarding preamble puncturing applied to the second 80 MHz band (i.e., information regarding a preamble puncturing pattern). Meanwhile, the UHR-SIG following the first U-SIG may include information regarding preamble puncturing applied to the second 80 MHz band (i.e., information regarding a preamble puncturing pattern), and the UHR-SIG following the second U-SIG may include information regarding preamble puncturing applied to the first 80 MHz band (i.e., information regarding a preamble puncturing pattern).
[0121] Additionally or generally, U-SIG and UHR-SIG may include information regarding preamble puncturing based on the following method. U-SIG may include information regarding preamble puncturing for all bands (i.e., information regarding preamble puncturing patterns). That is, UHR-SIG may not include information regarding preamble puncturing, and only U-SIG may include information regarding preamble puncturing (i.e., information regarding preamble puncturing patterns).
[0122] U-SIGs can be configured in 20 MHz units. For example, if an 80 MHz PPDU is configured, U-SIGs can be duplicated. That is, four identical U-SIGs can be included within an 80 MHz PPDU. PPDUs exceeding the 80 MHz bandwidth may contain different U-SIGs.
[0123] The UHR-SIG of FIG. 5 may include control information for a receiving STA. The UHR-SIG may be transmitted through at least one symbol, and one symbol may have a length of 4 us. Information regarding the number of symbols used for the UHR-SIG may be included in the U-SIG.
[0124] UHR-SIG provides additional signals to the U-SIG field, enabling the STA to interpret / decode the UHR PPDU. The UHR-SIG field may include U-SIG overflow bits that apply commonly to all users. Additionally, the UHR-SIG field contains resource allocation information, making it possible for the STA to look up resources used in fields containing data fields / UHR-STF / UHR-LTF (i.e., UHR modulated fields of an UHR PPDU).
[0125] The frequency resources of the UHR-LTF, UHR-STF, and data fields illustrated in FIG. 5 can be determined based on a RU (resource unit) defined by a plurality of subcarriers / tones. That is, the UHR-LTF, UHR-STF, and data fields of this specification can be transmitted / received through a RU (resource unit) defined by a plurality of subcarriers / tones.
[0126] FIG. 6 is a diagram showing the arrangement of resource units (RUs) used for a 20 MHz PPDU. That is, UHR-LTF, UHR-STF and / or data fields included in the 20 MHz PPDU can be transmitted / received through at least one of the various RUs defined in FIG. 6.
[0127] As shown at the top of Fig. 6, 26 units (i.e., units corresponding to 26 tones) may be arranged. Six tones may be used as a guard band in the leftmost band of the 20 MHz band, and five tones may be used as a guard band in the rightmost band of the 20 MHz band. Additionally, seven DC tones are inserted into the center band, i.e., the DC band, and 26 units corresponding to 13 tones may exist on the left and right sides of the DC band. Furthermore, 26 units, 52 units, and 106 units may be allocated to other bands. Each unit may be allocated for a receiving station, i.e., a user.
[0128] Meanwhile, the RU arrangement of Fig. 6 is utilized not only for situations involving multiple users (MU) but also for situations involving a single user (SU), in which case it is possible to use one 242-unit as shown at the bottom of Fig. 4, and in this case, three DC tones can be inserted.
[0129] In the example of FIG. 6, various sizes of RUs, namely 26-RU, 52-RU, 106-RU, 242-RU, etc., are proposed. Since the specific size of these RUs can be expanded or increased, the present embodiment is not limited to the specific size of each RU (i.e., the number of corresponding tones). In this specification, N-RU may be indicated as N-tone RU, etc. For example, 26-RU may be indicated as 26-tone RU.
[0130] Figure 7 is a diagram showing the arrangement of resource units (RU) used for a 40 MHz PPDU.
[0131] Just as various sizes of RUs were used in the example of FIG. 6, 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, etc., may also be used in the example of FIG. 7. Additionally, 5 DC tones may be inserted at the center frequency, 12 tones may be used as guard bands in the leftmost band of the 40 MHz band, and 11 tones may be used as guard bands in the rightmost band of the 40 MHz band.
[0132] In addition, as described, 484-RU may be used when used for a single user. Meanwhile, the specific number of RUs may be changed, as in the example of FIG. 6.
[0133] FIG. 8 is a diagram showing the arrangement of resource units (RUs) used for an 80 MHz PPDU. The arrangement of resource units (RUs) used in this specification may be varied. For example, the arrangement of resource units (RUs) used in the 80 MHz band may be varied.
[0134] FIG. 9 illustrates the operation according to UL-MU. As illustrated, a transmitting STA (e.g., AP) can establish a channel connection through contending (i.e., Backoff operation) and transmit a Trigger frame (930). That is, the transmitting STA (e.g., AP) can transmit a PPDU containing the Trigger frame (930). When the PPDU containing the Trigger frame is received, a TB (trigger-based) PPDU is transmitted after a delay of SIFS.
[0135] TB PPDUs (941, 942) may be transmitted at the same time and may be transmitted from multiple STAs (e.g., User STAs) with AIDs indicated within the Trigger frame (930). The ACK frame (950) for the TB PPDU may be implemented in various forms.
[0136] Figure 10 shows an example of a channel used / supported / defined within the 2.4 GHz band.
[0137] The 2.4 GHz band may be referred to by other names, such as the first band (band). Additionally, the 2.4 GHz band may refer to a frequency range in which channels with a center frequency adjacent to 2.4 GHz (e.g., channels with a center frequency located between 2.4 and 2.5 GHz) are used / supported / defined.
[0138] The 2.4 GHz band may include multiple 20 MHz channels. The 20 MHz channels within the 2.4 GHz band may have multiple channel indices (e.g., indices 1 through 14). For example, the center frequency of a 20 MHz channel assigned to channel index 1 may be 2.412 GHz, the center frequency of a 20 MHz channel assigned to channel index 2 may be 2.417 GHz, and the center frequency of a 20 MHz channel assigned to channel index N may be (2.407 + 0.005*N) GHz. Channel indices may be referred to by various names, such as channel numbers. The specific numerical values of channel indices and center frequencies may change.
[0139] FIG. 10 illustrates four channels within a 2.4 GHz band as an example. The illustrated first frequency range (1010) to fourth frequency range (1040) may each include one channel. For example, the first frequency range (1010) may include channel 1 (a 20 MHz channel having index 1). In this case, the center frequency of channel 1 may be set to 2412 MHz. The second frequency range (1020) may include channel 6. In this case, the center frequency of channel 6 may be set to 2437 MHz. The third frequency range (1030) may include channel 11. In this case, the center frequency of channel 11 may be set to 2462 MHz. The fourth frequency range (1040) may include channel 14. In this case, the center frequency of channel 14 may be set to 2484 MHz.
[0140] FIG. 11 illustrates an example of a channel used / supported / defined within the 5 GHz band.
[0141] The 5 GHz band may be referred to by other names such as the second band / band. The 5 GHz band may refer to a frequency range in which channels with a center frequency of 5 GHz or higher and less than 6 GHz (or less than 5.9 GHz) are used / supported / defined. Alternatively, the 5 GHz band may include multiple channels between 4.5 GHz and 5.5 GHz. The specific figures shown in FIG. 11 may be changed.
[0142] Multiple channels within the 5 GHz band include UNII (Unlicensed National Information Infrastructure)-1, UNII-2, UNII-3, and ISM. UNII-1 may be referred to as UNII Low. UNII-2 may include frequency regions referred to as UNII Mid and UNII-2 Extended. UNII-3 may be referred to as UNII-Upper.
[0143] Multiple channels may be configured within the 5 GHz band, and the bandwidth of each channel may be varied, such as 20 MHz, 40 MHz, 80 MHz, or 160 MHz. For example, the 5170 MHz to 5330 MHz frequency range within UNII-1 and UNII-2 may be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency range may be divided into four channels through a 40 MHz frequency range. The 5170 MHz to 5330 MHz frequency range may be divided into two channels through an 80 MHz frequency range. Alternatively, the 5170 MHz to 5330 MHz frequency range may be divided into one channel through a 160 MHz frequency range.
[0144] FIG. 12 illustrates an example of a channel used / supported / defined within the 6 GHz band.
[0145] The 6 GHz band may be referred to by other names such as the third band / band. The 6 GHz band may refer to a frequency range in which channels with a center frequency of 5.9 GHz or higher are used / supported / defined. The specific figures shown in FIG. 12 are subject to change.
[0146] For example, the 20 MHz channel of FIG. 12 can be defined starting from 5.940 GHz. Specifically, the leftmost channel among the 20 MHz channels of FIG. 12 may have index 1 (or channel index, channel number, etc.), and the center frequency may be assigned as 5.945 GHz. That is, the center frequency of the index N channel may be determined as (5.940 + 0.005*N) GHz.
[0147] Accordingly, the indices (or channel numbers) of the 20 MHz channel in FIG. 12 are 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, 197, It may be 201, 205, 209, 213, 217, 221, 225, 229, 233. Also, according to the (5.940 + 0.005*N) GHz rule described above, the index of the 40 MHz channel of FIG. 12 may be 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227.
[0148] The structure and types / subtypes of MAC frames are described below.
[0149] FIG. 13 shows an example of a MAC frame header. As illustrated, the MAC frame may include a frame control field / information of 2 octets, a duration field / information of 2 octets, a Receiver Address (RA) field / information of 6 octets, and a Transmitter Address (TA) field / information of 6 octets. As illustrated in FIG. 13, the four fields may be consecutive. The MAC header of FIG. 13 may be modified in various ways, and a new field may be inserted between the four illustrated fields, or at least one of the illustrated fields may be omitted.
[0150] The MAC header shown in FIG. 13 may be located at the very beginning of the MAC frame. That is, the MAC frame may include a MAC header such as that in FIG. 13 and a MAC body field / information following the MAC header. The MAC frame containing the MAC header of FIG. 13 is inserted / included in the data field of the PPDU (e.g., UHR PPDU) shown in FIG. 5.
[0151] MAC frames included in the data fields of the PPDU of this specification may be classified into various types. For example, MAC frames of this specification may be classified into control frames, management frames, and data frames.
[0152] For example, a management frame includes Association Request, Association Response, Reassociation Request, Reassociation Response, Probe Request, Probe Response, Beacon, Disassociation, Authentication, and Deauthentication frames / signals defined in conventional WLANs. For the management frame, the values of the type fields (B3 and B2) in FIG. 13 are set to 00. Additionally, the values of the subtype fields (B7, B6, B5, B4) in FIG. 13 are as follows: Association Request (0000), Association Response (0001), Reassociation Request (0010), Reassociation Response (0011), Probe Request (0100), Probe Response (0101), Beacon (1000), Disassociation (1010), Authentication (1011), Deauthentication (1100).
[0153] For example, the control frame includes the Trigger Beamforming Report Poll, NDP Announcement (NDPA), Control Frame Extension, Control Wrapper, Block Ack Request (BlockAckReq), Block Ack (BlockAck), PS-Poll, RTS, CTS, Ack, and CF-End frames / signals defined in conventional WLANs. For the control frame, the values of the type fields (B3 and B2) in FIG. 13 are set to 01. Also, the values of the subtype fields (B7, B6, B5, B4) of FIG. 13 are as follows: Trigger(0010), Beamforming Report Poll(0100), NDP Announcement(0101), Control Frame Extension(0110), Control Wrapper(0111), BlockAckReq(1000), BlockAck(1001), PS-Poll(1010), RTS(1011), CTS(1100), Ack(1101), CF-End(1110).
[0154] For example, the data frame includes (QoS) Data, (QoS) Null, etc., defined in conventional WLANs. For the management frame, the value of the type field (B3 and B2) in FIG. 13 is set to 10.
[0155] MAC frames / signals used in this specification can be identified through the type field / information and subtype field / information described above. For example, the “frame” in this specification may refer to a MAC frame in which the type bits B3 and B2 within the frame control field of the MAC header are set to 01, and the subtype bits B7, B6, B5, and B4 within the frame control field are set to 0010. Various MAC frames described in this specification are inserted into / included in the data fields of various PPDUs (e.g., HE / VHT / HE / EHT / UHR PPDU).
[0156] FIG. 14 shows a modified example of a transmitting device and / or receiving device of the present specification.
[0157] The device illustrated in FIGS. 1 to 4 (e.g., AP STA, non-AP STA) can be modified as in FIG. 14. The transceiver (630) in FIG. 14 may be identical to the transceiver (113, 123) in FIG. 1. The transceiver (630) in FIG. 14 may include a receiver and a transmitter.
[0158] The processor (610) of FIG. 14 may be the same as the processor (111, 121) of FIG. 1. Or, the processor (610) of FIG. 14 may be the same as the processing chip (114, 124) of FIG. 1.
[0159] The memory (150) of FIG. 14 may be the same as the memory (112, 122) of FIG. 1. Alternatively, the memory (150) of FIG. 14 may be a separate external memory different from the memory (112, 122) of FIG. 1.
[0160] Referring to FIG. 14, a power management module (611) manages power for a processor (610) and / or a transceiver (630). A battery (612) supplies power to the power management module (611). A display (613) outputs results processed by the processor (610). A keypad (614) receives input to be used by the processor (610). The keypad (614) may be displayed on the display (613). A SIM card (615) may be an integrated circuit used to securely store an international mobile subscriber identity (IMSI) and associated keys used to identify and authenticate a subscriber in a mobile device such as a mobile phone and a computer.
[0161] Referring to FIG. 14, the speaker (640) can output sound-related results processed by the processor (610). The microphone (641) can receive sound-related inputs to be used by the processor (610).
[0162] 1. Secondary channel
[0163] This specification proposes a secondary channel access process, and first defines the primary channel and the secondary channel as follows.
[0164] The primary channel is a common operating channel for all STAs that are members of the BSS, and in a 20MHz, 40MHz, 80MHz, 160MHz, 80+80MHz, or 320MHz BSS, the primary channel is the primary 20MHz channel.
[0165] A secondary channel is a channel associated with a primary channel used to create a channel wider than the primary channel, and in 40 MHz, 80 MHz, 160 MHz, 80+80 MHz, or 320 MHz BSS, the secondary channel is a secondary 20 MHz channel. The above secondary channel may also be referred to as a non-primary channel or a Non-Primary Channel Access (NPCA) primary channel. Furthermore, SCA (Secondary Channel Access) may also be referred to as NPCA (Non-Primary Channel Access). In the specification described below, these terms will be used interchangeably.
[0166] 2. How to perform Non-Primary Channel Access (NPCA) or Secondary Channel Access (SCA)
[0167] Currently, 802.11 performs channel access based on the primary channel. That is, an STA can transmit frames, including secondary channels that are IDLE, only when the primary channel is IDLE and the back-off counter (BC) becomes zero; to achieve this, all STAs perform Clear Channel Assessment (CCA) with priority given to the primary channel. Therefore, APs announce the primary channel of the BSS and always include the primary channel to transmit management frames, such as Beacon and Probe Response frames. While this mechanism is effective for protection as it allows frame exchange between all STAs and APs to be performed without interference, it is inefficient from the perspective of medium usage because access to secondary channels that are IDLE is not possible when only the primary channel is BUSY.
[0168] FIG. 15 illustrates an example of channel access in an 802.11 wireless LAN system.
[0169] FIG. 15 shows channel access based on the primary channel at 80 MHz bandwidth. As shown in FIG. 15, the following terms are used in this specification.
[0170] P20: Primary 20MHz Channel
[0171] S20: Secondary 20MHz Channel (If Bandwidth is 40MHz, it refers to the remaining 20MHz secondary channel excluding P20)
[0172] S40: Secondary 40MHz Channel (If Bandwidth is 80MHz, it refers to the remaining 40MHz secondary channel excluding P20 / S20)
[0173] S80: Secondary 80MHz Channel (If Bandwidth is 160MHz, it refers to the remaining 80MHz secondary channels excluding P20 / S20 / S40)
[0174] S160: Secondary 160MHz Channel (When Bandwidth is 320MHz, it refers to the remaining 160MHz secondary channels excluding P20 / S20 / S40 / S80)
[0175] S320: Secondary 320MHz Channel (When Bandwidth is 640MHz, it refers to the remaining 320MHz secondary channels excluding P20 / S20 / S40 / S80 / S160)
[0176] If P20 is in a BUSY state, such as CCA or NAV (Network Allocation Vector), it does not reduce BC and waits until it becomes IDLE. Through this back-off process, when BC becomes 0, it checks the channel status of S20 and S40 (i.e., CCA) and transmits the frame. In this example, since S40 is BUSY, the STA transmits a frame corresponding to a 40MHz PPDU through P20 and S20.
[0177] As mentioned above, as shown in FIG. 15, when P20 is BUSY and S20 and S40 are IDLE, the efficiency of medium usage is reduced because bandwidth corresponding to 60 MHz is wasted. Therefore, this specification proposes a method for accessing the secondary channel when P20 is BUSY.
[0178] Designations (names) in this specification may be changed, and STA may include AP STA or non-AP STA.
[0179] 2.2 Secondary channel access method
[0180] 2.2.1 STA Capabilities for Secondary Channel Access
[0181] Basically, capabilities for Secondary Channel Access (SCA) can be defined. For example, the STA and AP can inform each other whether SCA capabilities are supported or enabled. SCA capabilities can be determined by the first type of CCA (referred to as preamble detection (PD)), which is capable of identifying Wi-Fi frames performed on the Primary Channel (PCH), that is, whether frames can be decoded on the Secondary Channel (SCH). Through this, NAV can be configured on the SCH as well.
[0182] - Level 0: No Back-off on SCH: SCH performs Type 2 CCA as before. That is, it performs CCA that detects Wi-Fi signals (referred to as guard interval detection (GID)), CCA that detects signals of a certain strength or higher (referred to as energy detection (ED)), etc.
[0183] - Level 1: Back-off on a SCH at a time: PD, which is a Type 1 CCA, is performed on only one secondary channel at a time. (i.e., CCA performed on multiple SCHs simultaneously is not possible.)
[0184] - Level 2: Back-off on SCHs at the same time: Perform PD, which is a Type 1 CCA, on one or more secondary channels simultaneously. (i.e., CCA performed on multiple SCHs simultaneously is possible.)
[0185] These capabilities may be included in UHR capabilities, IE, etc. For example, information about these capabilities may be included and transmitted in Beacon, Probe Response frame, (Re)Association Request frame from the AP perspective, and in Probe Request frame, (Re)Association Request frame from the non-AP STA perspective.
[0186] 2.2.2 Basic Procedure of Secondary Channel Access
[0187] For the aforementioned STA, two NAVs can be set: a Basic NAV and an intra-BSS NAV. The Basic NAV may be updated based on a PPDU identified as inter-BSS, or based on a PPDU that cannot be identified as inter-BSS or intra-BSS. The intra-BSS NAV may be updated based on a PPDU identified as intra-BSS.
[0188] Basically, if Intra-BSS NAV is configured in the STA PCH, the following situations may occur.
[0189] - When an AP exchanges frames with a STA within a TXOP it has acquired, the other STA is configured with an intra-BSS NAV based on the primary channel as a result. In this case, if the STA with the intra-BSS NAV configured accesses the SCH and transmits a frame to the AP, the AP cannot receive it (i.e., the frame on the SCH transmitted from the STA to the AP) when the AP transmits it (e.g., DL Data, Ack, etc.).
[0190] Therefore, STA can perform SCA if a Basic NAV from a BSS other than its own (i.e., OBSS) is set in PCH.
[0191] In other words, STA can perform SCA when Basic NAV is set in PCH.
[0192] Figure 16 illustrates an example of the basic procedure of SCA.
[0193] Figure 16 illustrates the basic SCA process. If Basic NAV is set while the STA is performing back-off at P20, back-off is performed at S20 at the time the NAV is set. (Switching delay may occur for PD from P20 to S20.) This differs from the CCA method in that CCA can be performed at S20, and it can be performed at all levels. The reason for performing back-off at S20 is that if neighboring STAs with the same or similar Operation channel as this STA do not perform back-off and simultaneously transmit frames while in IDLE, collisions may occur, which could result in channel waste.
[0194] The considerations when performing SCA are as follows.
[0195] i) TXOP Configuration Method
[0196] Since CCA must be performed on P20 by default when the Basic NAV in P20 expires, the TXOP in SCH is set so that the end time of the TXOP ends before the time when the Basic NAV expires.
[0197] If the TXOP is set to terminate after the Basic NAV expires, a problem arises where the AP cannot receive frames because Legacy STAs, etc., can transmit frames via P20 after the Basic NAV set for the STA. Additionally, if the target beacon transmission time (TBTT) is set in the middle of the Basic NAV, problems may occur because the AP must prepare to transmit the beacon immediately after the Basic NAV. Furthermore, non-AP STAs also face the issue of waiting longer than scheduled because they cannot receive the beacon that the AP needs to transmit on time. Therefore, normal frame exchange can be performed at P20 by applying the condition that 'the TXOP's end time is set to terminate before the Basic NAV expires.'
[0198] => If there is not enough time to catch a TXOP, the frame is not transmitted. That is, if it is difficult to catch a TXOP for the interval between when the Back-off counter (BC) in the SCH is 0 and when the Basic NAV in the PCH ends, the frame is not transmitted.
[0199] ii) Frame transmission method
[0200] Previously, P20 had to be idle to perform puncturing based on whether the SCHs were idle or busy, thereby enabling the transmission of a frame. Therefore, for SCA, the rule is changed to account for the situation where P20 is busy. That is, when P20 is busy, P20 is punctured, and other SCH(s) that are busy based on S20 are also punctured to transmit a frame to the idle SCH(s). For example, Figure 16 shows a case where all three 20MHz channels of S20 and S40 are idle, and the AP transmits an 80MHz PPDU (including a MAC frame) to the STA, and the PPDU can provide a signal indicating that P20 has been punctured.
[0201] In addition, for back-off for SCA, a method different from the BC setting method in the existing PCH is required, and is as follows.
[0202] - How to Set EDCA Parameter Set
[0203] FIG. 17 illustrates an example of the EDCA Parameter Set element format of an 802.11 wireless LAN system.
[0204] Option 1: For SCA, the BC can be set using parameters (CWmax, CWmin, AIFSN) defined in the existing MU EDCA Parameter Set IE. That is, the CW parameter value is updated based on CWmin and CWmax defined in the MU EDCA Parameter Set IE, and the BC can be set. This allows the priority for SCA to be lowered because the SCH of the BSS where the corresponding STA is operating may be the PCH of another BSS.
[0205] Option 2: Define a new EDCA Parameter Set IE to be used in SCA. Since the current channel conditions of PCH and SCH may differ, define a new EDCA Parameter Set IE tailored to the SCH's channel conditions to enable BC configuration using the parameters defined in the new EDCA Parameter Set IE. Therefore, the AP needs to announce the new EDCA Parameter Set. However, this may increase implementation complexity, such as memory and overhead, required to maintain and announce additional EDCA parameters for SCA.
[0206] The EDCA parameter set for SCA, that is, for SCH, can use the following methods.
[0207] Option 2-1: A secondary channel EDCA parameter set IE can be defined by reusing the EDCA parameter set IE format considered for each AC, similar to the EDCA parameter set IE used in the existing PCH. That is, by reusing the format of FIG. 17, the AP can announce an additional EDCA parameter set for SCA based on the said format (referred to as the secondary channel EDCA parameter set in this specification). The STA stores the secondary channel EDCA parameter set for the Beacon or the most recently received SCH and uses these parameters during SCA. For example, the CW parameter value is updated based on CWmin and CWmax for each AC, and the BC can be selected based on this.
[0208] Through the above option, you can see that the BC for SCH is also maintained by AC.
[0209] Option 2-2: Announce only a single integrated AC, i.e., a single CW (Contention Window), AIFSn, TXOP Limit, etc., instead of all ACs. This reduces the overhead associated with the EDCA parameter set that must be maintained for SCA. This has the advantage of allowing for the rapid transmission of traffic that requires urgent delivery during SCA (e.g., traffic requiring low latency). In other words, when BC = 0, traffic requiring rapid transmission from each queue can be sent preferentially.
[0210] Option 3: Select the BC in SCH based on the AC and CW parameters of the existing PCH. (i.e., select based on the parameters of the EDCA Parameter Set IE in Fig. 17). In other words, the BC value is set by sharing the same CW parameter value between the PCH and SCH. This reduces complexity in terms of implementation because it does not maintain additional EDCA parameters for SCA. However, for example, if the CW parameter has a high value due to poor channel conditions in P20, the CW parameter may be applied inappropriately when the channel conditions in S20 are good, resulting in an inappropriate BC value being set in SCH.
[0211] Option 4: The parameters (CWmax, CWmin, AIFSN) defined in the existing PCH's EDCA Parameter Set IE are shared, but the CW parameter maintains a value separate from the PCH and is updated so that the SCH selects the BC. (i.e., selected based on the parameters of the EDCA Parameter Set IE in Fig. 17). That is, the initial value of the SCH's CW parameter is set to the same CWmin value as the PCH by utilizing the CWmin defined in the PCH's EDCA Parameter Set IE, but the CW parameter value is updated separately according to each channel condition or transmission failure, allowing the setting of a BC value that takes into account each channel condition or transmission failure. This can reduce the signaling overhead of announcing an additional EDCA Parameter Set IE for SCA.
[0212] Option 5: APs after 802.11ax announce the MU EDCA Parameter Set that non-AP STAs must use after transmitting the EDCA Parameter Set and the UL (Uplink) MU (Multi User) HE (High Efficiency) TB (Trigger Based) PPDU.
[0213] Additionally or alternatively, a new EDCA Parameter Set to be used in SCA, such as option 2, can be announced.
[0214] - SCA EDCA Parameter Set Indication: Indicates which EDCA Parameter Set non-AP STAs performing channel access in SCH utilize.
[0215] For example, when it has a 2-bit value (which can change), it can be defined as follows.
[0216] 0: Indicates that the MU EDCA Parameter Set is used in SCH
[0217] 1: Indicates that SCH uses the same EDCA parameter set as PCH.
[0218] 2: Indicates that the EPCS (Emergency Preparedness Communication Services) EDCA Parameter Set is used in SCH
[0219] 3: Indicates the use of a new EDCA Parameter Set for SCH
[0220] For example, there is an advantage in that the AP can adjust the priority for non-AP STAs performing channel access in the PCH and SCH. That is, if you want to reduce the priority for non-AP STAs performing channel access in the SCH, you can set the above SCA EDCA Parameter Set Indication to 0, and otherwise, you can set it to 1. If you want to give a higher priority in the SCH, you can set the above SCA EDCA Parameter Set Indication to 2.
[0221] => The advantage is that the AP can adjust the priority for non-AP STAs performing channel access on the SCH.
[0222] The relevant indication can be included in and transmitted to the UHR Operation IE of the Beacon / Probe Response / Association Response.
[0223] Additionally or alternatively, when the SCA EDCA Parameter Set Indication is set to 1, CW may be maintained as a single value in PCH and SCH and updated, or may be maintained as a separate value and updated.
[0224] - CW setting method
[0225] The CW setting method Option 1 and Option 2 assume Option 2 of the BC setting method above. That is, the BC value is set based on separate CW parameters in PCH and SCH through different EDCA parameter sets in PCH and SCH.
[0226] Additionally or alternatively, the methods of Option 1 and Option 2 of the CW setting method may also be applied to Option 3 of the above BC setting method, that is, the method of setting BC values based on the same CW value and utilizing the same EDCA Parameter Set in PCH and SCH.
[0227] FIG. 18 illustrates an example of Option 1, which maintains the CW value of SCH when switching to SCH.
[0228] Option 1: When switching to SCH, there may be a method to maintain the CW value of the SCH as is. As shown in Fig. 18, when performing SCA on the SCH, the initial CW value is set to CWmin (i.e., 7). This is a case where the Init (Initial) Control frame fails to transmit twice, increasing from 7 to 15 initially, and then increasing from 15 to 31 upon the second failure. In a situation where a successful frame exchange on the SCH is not performed and the system returns to the PCH, and Basic NAV is set on the PCH to perform SCA on the SCH, the BC value on the SCH is set while maintaining the previous CW value. That is, the CW value is used as is for the previously performed SCA, so the CW value is set to 31 when performing the second SCA to extract the BC value. Subsequently, upon receiving the Init Control Response frame, it can be confirmed that the CW value is reset to CWmin and set to 7. Utilizing this option has the advantage of reducing frame collisions because it allows setting a BC value that accurately reflects the poor channel conditions of the SCH while performing SCA.
[0229] FIG. 19 illustrates an example of Option 2, which initializes the CW value of SCH to CWmin when switching to SCH.
[0230] Option 2: When switching to SCH, there may be a method to initialize the SCH CW value to CWmin.
[0231] Additionally or alternatively, the CW value of SCH can have any value greater than or equal to 0, other than CWmin.
[0232] Additionally or alternatively, the CW value of SCH can have any value greater than or equal to CWmin, rather than CWmin.
[0233] Additionally, or alternatively, when the CW value of SCH is initialized to CWmin or a value other than CWmin, AP may define and announce a field regarding which value to initialize as the CW value. In this embodiment, the field containing information related to the initialization of the CW value of SCH is referred to as the Rules for CW field.
[0234] For example, when the Rules for CW field is composed of 4 bits, if the Rules for CW field is 0, it may mean that the CWmin value announced in the EDCA Parameter Set is used as is. If the Rules for CW field is 1, it may mean that the CW value is initialized to half of the CWmin value. If the Rules for CW field is 2, it may mean that the CW value is initialized to twice the CWmin value. If the Rules for CW field is 3, it may mean that the CW value is initialized to the CWmin value. Through this, there is an advantage in that when the number of STAs performing SCA is small, the CWmin value is reduced to allow STAs to perform channel access more quickly, while in environments where there are many issues with medium sync, the CWmin value is increased to flexibly perform more conservative channel access. AP can transmit the above Rules for CW field along with the EDCA Parameter Set by including it in the UHR Operation IE of the Beacon / Probe Response / Association Response.
[0235] As shown in Fig. 19, when performing SCA in the SCH, the initial CW value is set to CWmin (i.e., 7), and when the Init Control frame fails to transmit twice, it increases from 7 to 15 initially, and then increases from 15 to 31 upon the second failure. Unlike Option 1, when returning to the PCH even if a successful frame exchange is not performed in the SCH, and the Basic NAV is set in the PCH to perform SCA in the SCH, the previous CW value is not maintained as is, but the initialized BC value in the SCH is set. That is, when performing the second SCA, the BC value is extracted using the value of 7, which is the CWmin value, rather than the CW value of 31. While utilizing this option has the advantage of granting more channel access opportunities to the STA performing SCA, it has the disadvantage that in an environment where the PCH of the OBSS and the SCH performing Back-off overlap, the channel access opportunities based on the PCH of the OBSS may be reduced.
[0236] - BC (Back-off counter) setting method
[0237] FIG. 20 illustrates an example of Option 1, which maintains the BC value of SCH when switching to SCH.
[0238] Option 1: When switching to an SCH, there may be a method to maintain the BC value that was previously maintained in the SCH. As shown in Fig. 20, when performing SCA in an SCH, the STA sets the BC value to 14 to perform Back-off, and then switches to the PCH to switch to the PCH before the Basic NAV in the PCH expires when the BC value is 6. At this time, when switching to the next SCH while maintaining that value, the STA starts frame exchange by decreasing the BC value starting from the previously remaining BC value of 6, and begins frame exchange when the BC value becomes 0. Utilizing this option has the advantage of being fair in terms of channel access opportunities, as STAs that were performing contention in the SCH can restart contention in a subsequent SCH while maintaining their BC values.
[0239] Additionally or alternatively, when maintaining the BC value, option 1 of the CW setting method described above may be applied together with option 2. FIG. 21 is an example in which the BC value and the CW value are set in a combined form of option 2 of the CW setting method and option 2 of the BC setting method.
[0240] FIG. 21 illustrates an example of Option 2, which sets a new BC value of SCH when switching to SCH.
[0241] Option 2: When switching to SCH, there may be a method of extracting a new BC value from [0,CW]. As shown in Fig. 21, when performing SCA in SCH, the STA sets the BC value to 14 and performs Back-off, and when the BC value is 6, it switches to PCH to switch to PCH before the Basic NAV in PCH expires. Subsequently, when switching to the next SCH, the STA extracts a new BC value (from [0,CW]) and starts frame exchange when the BC value becomes 0.
[0242] Additionally or alternatively, when setting a new BC value, option 1 of the CW setting method described above may be applied together with option 2. FIG. 21 is an example in which the BC value and the CW value are set in a combined form of option 2 of the CW setting method and option 2 of the BC setting method.
[0243] <SCA에 대한 STA의 동작과정 #1>
[0244] - Here, STA can be a non-AP STA or an AP.
[0245] In the present disclosure, an STA performing SCA may transmit frames / PPDUs on a SCH even during the time when NAV is set in the PCH. For example, an STA may transmit frames (or PPDUs) excluding (or puncturing) the PCH on one or more SCHs in an IDLE state determined by backoff performed on one or more SCHs and CCA results of one or more SCHs where backoff is not performed.
[0246] Additionally or alternatively, a TXOP initiated by the transmission of a frame or PPDU on the SCH may be set to terminate before the NAV on the PCH is terminated. The length of the TXOP may be set / indicated through the duration / ID field of the corresponding frame. For example, the value of the duration / ID field may be set to a value that is the time (including the inter-frame interval (IFS)) required for the exchange of a frame or PPDU following the corresponding frame or PPDU.
[0247] Additionally or alternatively, the EDCA Parameter Set for each SCH where Back-off is performed can be set to the EDCA Parameter Set in the PCH, the MU EDCA Parameter Set, or a new EDCA Parameter Set. This EDCA Parameter Set can be applied identically or differently to all SCHs.
[0248] Additionally or alternatively, the EDCA Parameter Set for SCH can utilize the EDCA Parameter Set from PCH, but the CW value for extracting the BC value can be updated separately in PCH and SCH.
[0249] In the present disclosure, an STA receiving a frame transmitted via an SCA may perform frame detection on the SCH even during the time when a NAV is set in the PCH. For example, the STA may perform backoff on the SCH if there is a frame to transmit, or it may attempt to receive whether there is a frame addressed to it on the SCA even if there is no frame to transmit. Additionally, the STA may set or reset the NAV based on the value of the duration / ID field of the frame detected on the SCH.
[0250] Additionally or alternatively, the EDCA Parameter Set for each SCH where Back-off is performed can be set to the EDCA Parameter Set in the PCH, the MU EDCA Parameter Set, or a new EDCA Parameter Set. This EDCA Parameter Set can be applied identically or differently to all SCHs.
[0251] Additionally or alternatively, the EDCA Parameter Set for SCH can utilize the EDCA Parameter Set from PCH, but the CW value for extracting the BC value can be updated separately in PCH and SCH.
[0252] Additionally or alternatively, if AP announces both the EDCA Parameter Set and the MU EDCA Parameter Set, non-AP STAs can indicate whether to use the EDCA Parameter Set or the MU EDCA Parameter Set in SCH through the SCA EDCA Parameter Set indication.
[0253] Figure 22 illustrates the basic Secondary Channel Access operation process of an STA.
[0254] Referring to Fig. 22, the transmission process of the STA is as follows.
[0255] When the STA receives a PPDU containing a frame from another BSS, (Basic) NAV is set on the Primary channel. The STA performs Back-off on one or more 20 MHz Secondary channels. When the Back-off counter on the Secondary channel where the STA performed Back-off becomes 0, it performs CCA on the other Secondary channels. The STA transmits a PPDU containing a frame using a bandwidth that includes the Secondary channel where Back-off was performed and the other Secondary channels that are IDLE as a result of performing CCA.
[0256] Referring to Fig. 22, the reception process of the STA is as follows.
[0257] When an STA receives a PPDU containing a frame from another BSS, (Basic) NAV is set on the Primary channel. The STA performs Back-off on one or more 20 MHz Secondary channels. While performing Back-off, the STA receives a PPDU containing one or more frames and determines whether the frame is addressed to the STA (i.e., determines whether the Receiver address of the frame is the MAC address of the STA). If the frame is addressed to the STA, the STA decodes the frame body of the frame. If the frame is not addressed to the STA, the STA sets NAV by the value of the Duration field of the frame's MAC header.
[0258] <SCA에 대한 STA의 동작과정 #2>
[0259] - STA can be a non-AP STA or AP.
[0260] In the present disclosure, an STA performing SCA may transmit frames / PPDUs on a SCH even during the time when NAV is set in the PCH. For example, an STA may transmit frames or PPDUs excluding (or puncturing) the PCH on one or more SCHs in an IDLE state determined by backoff performed on one or more SCHs and CCA results of one or more SCHs where backoff is not performed.
[0261] Additionally or alternatively, a TXOP initiated by the transmission of a frame or PPDU on the SCH may be set to terminate before the NAV on the PCH is terminated. The length of the TXOP may be set / indicated through the duration / ID field of the corresponding frame. For example, the value of the duration / ID field may be set to a value that is the time (including the inter-frame interval (IFS)) required for the exchange of a frame or PPDU following the corresponding frame or PPDU.
[0262] Additionally or alternatively, the EDCA Parameter Set for each SCH where Back-off is performed can be set to the EDCA Parameter Set in the PCH, the MU EDCA Parameter Set, or a new EDCA Parameter Set. This EDCA Parameter Set can be applied identically or differently to all SCHs.
[0263] Additionally or alternatively, information on the maximum number of times a frame / PPDU can be transmitted on the SCH can be obtained from a Management frame (e.g., Beacon) transmitted by the AP. If the STA performing the SCA is an AP, it can use the information it transmitted (information on the maximum number of times a frame / PPDU can be transmitted).
[0264] => Additionally or alternatively, information on the maximum number of times a frame / PPDU can be transmitted can be determined by negotiation between the AP and the STA.
[0265] => Additionally or alternatively, if the number of times the STA has transmitted a frame / PPDU reaches the maximum number of times it can transmit a frame / PPDU, it may then wait for a frame that is addressed to the STA or a frame that is not addressed to the STA, i.e., a frame that can set the NAV.
[0266] => Additionally or alternatively, if the number of times the STA has transmitted a frame / PPDU reaches the maximum number of times it can transmit a frame / PPDU, then it may stop the SCA and switch back to the PCH to perform back-off.
[0267] => Additionally or alternatively, if the number of times the STA has transmitted a frame / PPDU reaches the maximum number of times it can transmit a frame / PPDU, it may then continuously perform back-off.
[0268] Additionally or alternatively, when STA switches to SCH to perform SCA, it may retain the BC value that remained from the previous Back-off in SCH.
[0269] Additionally, or alternatively, the CW value can be initialized to the CWmin value.
[0270] => Additionally or alternatively, the CW value can be maintained as the CW value from the previous SCH.
[0271] Additionally or alternatively, when STA switches to SCH to perform SCA, it can reset the BC value from [0,CW].
[0272] Additionally, or alternatively, the CW value can be initialized to the CWmin value.
[0273] => Additionally or alternatively, the CW value can be maintained as the CW value from the previous SCH.
[0274] In the present disclosure, an STA receiving a frame transmitted via an SCA may perform frame detection on the SCH even during the time when a NAV is set in the PCH. For example, the STA may perform backoff on the SCH if there is a frame to transmit, or it may attempt to receive whether there is a frame addressed to it on the SCA even if there is no frame to transmit. Additionally, the STA may perform NAV setting / resetting based on the value of the duration / ID field of the frame detected on the SCH.
[0275] Additionally or alternatively, the EDCA Parameter Set for each SCH where Back-off is performed can be set to the EDCA Parameter Set in the PCH, the MU EDCA Parameter Set, or a new EDCA Parameter Set. This EDCA Parameter Set can be applied identically or differently to all SCHs.
[0276] Additionally or alternatively, the EDCA Parameter Set for SCH can utilize the EDCA Parameter Set from PCH, but the CW value for extracting the BC value can be updated separately in PCH and SCH.
[0277] The PPDU to which the signal of the present specification is transmitted / received may include a data field.
[0278] The above data field includes user data and may include packets for the upper layer. That is, it may include MPDU (MAC Frame).
[0279] For example, the duration / ID field in the MAC header included in the MPDU may be set to a value containing the time length of a frame exchange following the frame or PPDU transmitted excluding (or puncturing) the PCH, if channel access operations on the secondary channel are supported. For example, the TXOP end time determined based on the value of the duration / ID field may be set before the end time of the NAV set on the primary channel.
[0280] In addition, as shown in Figure 1 above, the transmitting device and the receiving device may each include a memory, a processor, and a transceiver.
[0281] The above memory can store information regarding a plurality of Secondary Channel Accesses as described in this specification.
[0282] The above processor can perform back-off in the Secondary Channel based on the information stored in the memory, generate various RUs, and configure PPDUs. The above processor is described in this specification<SCA에 대한 STA의 동작과정 #1> ,<SCA에 대한 STA의 동작과정 #2> It can be configured to perform all or part of it.
[0283] In particular, the transceiver (113) of the transmitting device includes an antenna and can perform analog signal processing. Specifically, the processor (111) can control the transceiver (113) to transmit a PPDU generated by the processor (111).
[0284] Alternatively, the processor (111) may generate a transmission PPDU and store information regarding the transmission PPDU in memory (112).
[0285] For example, the processor (111) of the transmitting device may be configured to perform the operation of the transmitting STA according to the example of the present disclosure. For example, the processor (111) may be configured to transmit a frame on the SCH through the transceiver (113) during the time that NAV is set on the PCH. For example, the processor (111) may be configured to perform backoff on the SCH through the transceiver (113) and determine one or more SCHs in an IDLE state. For example, the processor (111) may be configured to transmit a frame / PPDU that excludes / punctures the PCH on one or more SCHs through the transceiver (113). Additionally or alternatively, the processor (111) may be configured to generate a frame including a duration / ID field set to a value such that a TXOP initiating the transmission of a frame / PPDU on the SCH is terminated before the time when NAV on the PCH is terminated.
[0286] Additionally, the transceiver (123) of the receiving device can receive PPDU based on the control of the processor (121). For example, the transceiver (123) may include a plurality of sub-units (not shown). For example, the transceiver (123) may include at least one receiving antenna and a filter for said receiving antenna.
[0287] The PPDU received through the transceiver (123) can be stored in memory (122). The processor (121) can process decoding for the received PPDU through memory (122). The processor (121) can obtain control information (e.g., SIG) regarding the BW / Tone-Plan / RU included in the PPDU and store the obtained control information in memory (122).
[0288] The processor (121) can perform decoding on the received PPDU. Additionally, the processor (121) can process the decoded data. For example, the processor (121) can perform a processing operation to transmit information regarding the decoded data field to an upper layer (e.g., MAC layer). Additionally, if the generation of a signal is directed from the upper layer to the PHY layer in response to the data transmitted to the upper layer, a subsequent operation can be performed.
[0289] For example, the processor parses the MAC PDU obtained through PHY decoding of the DATA field of the PPDU received through the transceiver.
[0290] For example, the processor (121) of the receiving device may be configured to perform the operation of the receiving STA according to the example of the present disclosure. For example, the processor (121) may attempt to detect a frame on the SCH through the transceiver (123) for a time during which the NAV is set on the PCH. The processor (121) may be configured to decode / parse the frame addressed to it based on the frame received on the SCH. Additionally, the processor (121) may be configured to set / reset the NAV according to the value of the duration / ID field of the frame not addressed to it.
[0291] FIG. 23 is a flowchart illustrating the operation of a transmitting device according to the present embodiment.
[0292] An example of FIG. 23 can be performed on a transmitting STA or a transmitting device (AP and / or non-AP STA).
[0293] Some of the steps of each example in FIG. 23 (or detailed sub-steps described later) may be omitted or changed.
[0294] Through step S2310, the transmitting device (transmitting STA) can obtain information regarding the above-described Tone Plan. As described above, the information regarding the Tone Plan includes the size and location of the RU, control information related to the RU, information regarding the frequency band in which the RU is included, information regarding the STA receiving the RU, etc.
[0295] Through step S2320, the transmitting device can construct / generate a PPDU based on acquired control information. The step of constructing / generating the PPDU may include the step of constructing / generating each field of the PPDU. That is, step S2320 includes the step of constructing an EHT-SIG field containing control information regarding a Tone Plan. That is, step S2320 may include the step of constructing a field containing control information (e.g., N bitmap) indicating the size / location of the RU and / or the step of constructing a field containing an identifier (e.g., AID) of the STA receiving the RU.
[0296] Additionally, step S2320 may include the step of generating an STF / LTF sequence transmitted through a specific RU. The STF / LTF sequence may be generated based on a pre-configured STF generation sequence / LTF generation sequence.
[0297] Additionally, step S2320 may include a step of generating a data field (i.e., MPDU) transmitted through a specific RU.
[0298] The transmitting device can transmit the PPDU configured through step S2320 to the receiving device based on step S2330.
[0299] While performing step S2330, the transmitting device may perform at least one of the following operations: CSD, Spatial Mapping, IDFT / IFFT operation, GI insertion, etc.
[0300] A signal / field / sequence configured according to the present specification can be transmitted in the form of FIG. 5.
[0301] FIG. 24 is a flowchart illustrating the operation of a receiving device according to the present embodiment.
[0302] The above-described PPDU can be received according to an example of FIG. 24.
[0303] An example of FIG. 24 can be performed on a receiving STA or a receiving device (AP and / or non-AP STA).
[0304] Some of the steps (or detailed sub-steps described later) of each example in FIG. 24 may be omitted.
[0305] A receiving device (receiving STA) can receive all or part of the PPDU through step S2410. The received signal may be in the form of FIG. 5.
[0306] The sub-step of step S2410 can be determined based on step S2330 of FIG. 23. That is, step S2410 can perform an operation to restore the results of the CSD, Spatial Mapping, IDFT / IFFT operation, and GI insert operation applied in step S2330.
[0307] In step S2420, the receiving device can perform decoding of all or part of the PPDU. Additionally, the receiving device can obtain control information related to the Tone Plan (i.e., RU) from the decoded PPDU.
[0308] More specifically, the receiving device can decode the L-SIG and EHT-SIG of the PPDU based on the Legacy STF / LTF and obtain information contained in the L-SIG and EHT-SIG fields. Information regarding various Tone Plans (i.e., RU) described in this specification may be included in the EHT-SIG, and the receiving STA can obtain information regarding the Tone Plan (i.e., RU) through the EHT-SIG.
[0309] In step S2430, the receiving device can decode the remainder of the PPDU based on information regarding the Tone Plan (i.e., RU) obtained through step S2420. For example, the receiving STA can decode the STF / LTF fields of the PPDU based on information regarding the one Plan (i.e., RU). Additionally, the receiving STA can decode the data fields of the PPDU based on information regarding the Tone Plan (i.e., RU) and obtain the MPDU contained in the data fields.
[0310] Additionally, the receiving device can perform a processing operation to transmit the decoded data through step S2430 to an upper layer (e.g., MAC layer). Furthermore, if the generation of a signal is instructed from the upper layer to the PHY layer in response to the data transmitted to the upper layer, a subsequent operation can be performed.
[0311] Hereinafter, the above-described embodiment will be explained with reference to FIGS. 1 to 24.
[0312] FIG. 25 is a flowchart illustrating a procedure in which an NPCA AP according to the present embodiment transmits information to initialize the CW value of an NPCA primary channel through a management frame.
[0313] An example of FIG. 25 can be performed in a network environment that supports a next-generation wireless LAN system (UHR (Ultra High Reliability) wireless LAN system or next wi-fi). The next-generation wireless LAN system is a wireless LAN system that improves upon the 802.11be system and can satisfy backward compatibility with the 802.11be system.
[0314] An example of FIG. 25 is performed in an NPCA AP, and the NPCA AP may be an AP that supports NPCA operation. The NPCA non-AP STA may be a non-AP STA that supports NPCA operation. The NPCA non-AP STA and the NPCA AP may set the NPCA Supported field of the UHR MAC Capabilities Information field of the UHR Capabilities element to 1. The NPCA AP having an operating bandwidth smaller than 80 MHz cannot enable the NPCA operation.
[0315] This embodiment proposes a method of signaling through a management frame by defining a field containing information related to the CW value of the NPCA primary channel. Specifically, assuming that the CW value of the NPCA primary channel is initialized to a value different from that of the BSS primary channel (existing primary channel), a method of configuring information used to initialize the CW value of the NPCA primary channel is proposed.
[0316] In step S2510, the NPCA (Non-primary channel access) AP (access point) transmits a management frame to the NPCA non-AP STA (station).
[0317] In step S2520, the NPCA AP performs backoff for the NPCA primary channel based on the management frame.
[0318] The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field.
[0319] The above Initial NPCA QSRC field contains information about a first value used to initialize the first CW (Contention Window) parameter for the above NPCA primary channel.
[0320] The above first CW parameter is initialized based on the above first value and the CW minimum value for the BSS (Basic Service Set) primary channel.
[0321] Specifically, the first CW parameter may be initialized to 2^Init_QSRC_NPCA x (CWmin[AC]+1)-1. The Init_QSRC_NPCA may be related to the first value. The CWmin[AC] may be related to the CW minimum value for the BSS primary channel.
[0322] The value of the backoff performed for the NPCA primary channel can be selected based on the initialized first CW parameter. That is, the value of the backoff for the NPCA primary channel can be selected within the minimum CW value set (or initialized) separately from the BSS primary channel (or primary 20 MHz channel).
[0323] Based on the backoff value performed for the NPCA primary channel being 0, the NPCA non-AP STA may transmit an ICF (Initial Control Frame) to the NPCA AP. The NPCA non-AP STA may receive an ICR (Initial Control Response) frame from the NPCA AP. (Alternatively, the NPCA AP may receive an ICF (Initial Control Frame) from the NPCA non-AP STA. The NPCA AP may transmit an ICR (Initial Control Response) frame to the NPCA non-AP STA.)
[0324] The first CW parameter may also increase exponentially whenever a transmission failure of the ICF occurs in the NPCA primary channel. However, based on the reception of the ICR, the increased first CW parameter may be reset to the initially set minimum CW value.
[0325] The above management frame may further include an Enhanced Distributed Channel Access (EDCA) parameter set element for the BSS primary channel.
[0326] The above EDCA parameter setting element may include information regarding the CW minimum value (or QSRC, backoff counter) for the BSS primary channel. The CW minimum value (or QSRC, backoff counter) for the BSS primary channel may be stored in the NPCA non-AP STA.
[0327] The above Initial NPCA QSRC field can be set to 4 bits.
[0328] For example, based on the Initial NPCA QSRC field being 0, the first CW parameter may use the minimum CW value for the BSS primary channel as is. Based on the Initial NPCA QSRC field being 1, the first CW parameter may be initialized to half the minimum CW value for the BSS primary channel. Based on the Initial NPCA QSRC field being 2, the first CW parameter may be initialized to twice the minimum CW value for the BSS primary channel. Based on the Initial NPCA QSRC field being 3, the first CW parameter may be initialized to the minimum CW value for the BSS primary channel.
[0329] The above management frame may be a beacon, a probe response frame, or a (re)association response frame. The beacon frame, the probe response frame, or the (re)association response frame may include an Ultra High Reliability (UHR) operation element. The UHR operation element may include the Initial NPCA QSRC field.
[0330] The above NPCA primary channel may be a non-primary channel (a channel other than the BSS primary channel) capable of performing backoff while a basic NAV (Network Allocation Vector) is set on the above BSS primary channel. The above basic NAV may be set by OBSS (Overlapping Basic Service Set) traffic. That is, through NPCA, STAs within the BSS (or NPCA STAs) may switch to an alternate channel during the period when OBSS activity is detected in part of the BSS operating channel.
[0331] That is, the present embodiment proposes a method for performing backoff for the NPCA primary channel by newly defining and signaling information related to the CW value of the NPCA primary channel, and selecting a backoff value within the minimum CW value that matches the NPCA primary channel state.
[0332] By newly defining and signaling information related to CW values set to reflect the congestion status or traffic load of the NPCA primary channel, the NPCA STA (NPCA non-AP STA or NPCA AP) can select a backoff value within the minimum CW value (CWmin) suitable for the state of the NPCA primary channel. Accordingly, the NPCA STA can perform the backoff procedure for the NPCA primary channel in a form optimized for the channel environment, and as a result, it has the effect of reducing the probability of collisions caused by media access contention and improving the utilization efficiency of the NPCA primary channel. In addition, by differentially adjusting the CW value according to the channel state, fairness in media access among NPCA STAs can be ensured, and traffic imbalance between the NPCA channel and the BSS primary channel can be mitigated, thereby improving the transmission delay and throughput performance of the overall BSS.
[0333] According to the NPCA operation procedure of the present specification, even when interference is present in the BSS primary channel in an OBSS environment, the NPCA STA has the effect of maintaining stable communication by switching to the NPCA primary channel. Accordingly, the NPCA STA can prevent data transmission from being interrupted by interference and can improve the spectrum utilization efficiency and transmission reliability of the entire BSS.
[0334] FIG. 26 is a flowchart illustrating a procedure for an NPCA non-AP STA according to the present embodiment to receive information through a management frame for initializing the CW value of an NPCA primary channel.
[0335] An example of FIG. 26 can be performed in a network environment that supports a next-generation wireless LAN system (UHR (Ultra High Reliability) wireless LAN system or next wi-fi). The next-generation wireless LAN system is a wireless LAN system that improves upon the 802.11be system and can satisfy backward compatibility with the 802.11be system.
[0336] An example of FIG. 26 is performed in an NPCA non-AP STA, and the NPCA non-AP STA may be a non-AP STA that supports NPCA operation. The NPCA AP may be an AP that supports NPCA operation. The NPCA non-AP STA and the NPCA AP may set the NPCA Supported field of the UHR MAC Capabilities Information field of the UHR Capabilities element to 1. The NPCA AP having an operating bandwidth smaller than 80 MHz cannot enable the NPCA operation.
[0337] This embodiment proposes a method of signaling through a management frame by defining a field containing information related to the CW value of the NPCA primary channel. Specifically, assuming that the CW value of the NPCA primary channel is initialized to a value different from that of the BSS primary channel (existing primary channel), a method of configuring information used to initialize the CW value of the NPCA primary channel is proposed.
[0338] In step S2610, the NPCA (Non-primary channel access) non-AP (non-access point) STA (station) receives a management frame from the NPCA AP.
[0339] In step S2620, the NPCA non-AP STA performs backoff for the NPCA primary channel based on the management frame.
[0340] The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field.
[0341] The above Initial NPCA QSRC field contains information about a first value used to initialize the first CW (Contention Window) parameter for the above NPCA primary channel.
[0342] The above first CW parameter is initialized based on the above first value and the CW minimum value for the BSS (Basic Service Set) primary channel.
[0343] Specifically, the first CW parameter may be initialized to 2^Init_QSRC_NPCA x (CWmin[AC]+1)-1. The Init_QSRC_NPCA may be related to the first value. The CWmin[AC] may be related to the CW minimum value for the BSS primary channel.
[0344] The value of the backoff performed for the NPCA primary channel can be selected based on the initialized first CW parameter. That is, the value of the backoff for the NPCA primary channel can be selected within the minimum CW value set (or initialized) separately from the BSS primary channel (or primary 20 MHz channel).
[0345] Based on the backoff value performed for the NPCA primary channel being 0, the NPCA non-AP STA may transmit an ICF (Initial Control Frame) to the NPCA AP. The NPCA non-AP STA may receive an ICR (Initial Control Response) frame from the NPCA AP. (Alternatively, the NPCA AP may receive an ICF (Initial Control Frame) from the NPCA non-AP STA. The NPCA AP may transmit an ICR (Initial Control Response) frame to the NPCA non-AP STA.)
[0346] The first CW parameter may also increase exponentially whenever a transmission failure of the ICF occurs in the NPCA primary channel. However, based on the reception of the ICR, the increased first CW parameter may be reset to the initially set minimum CW value.
[0347] The above management frame may further include an Enhanced Distributed Channel Access (EDCA) parameter set element for the BSS primary channel.
[0348] The above EDCA parameter setting element may include information regarding the CW minimum value (or QSRC, backoff counter) for the BSS primary channel. The CW minimum value (or QSRC, backoff counter) for the BSS primary channel may be stored in the NPCA non-AP STA.
[0349] The above Initial NPCA QSRC field can be set to 4 bits.
[0350] For example, based on the Initial NPCA QSRC field being 0, the first CW parameter may use the minimum CW value for the BSS primary channel as is. Based on the Initial NPCA QSRC field being 1, the first CW parameter may be initialized to half the minimum CW value for the BSS primary channel. Based on the Initial NPCA QSRC field being 2, the first CW parameter may be initialized to twice the minimum CW value for the BSS primary channel. Based on the Initial NPCA QSRC field being 3, the first CW parameter may be initialized to the minimum CW value for the BSS primary channel.
[0351] The above management frame may be a beacon, a probe response frame, or a (re)association response frame. The beacon frame, the probe response frame, or the (re)association response frame may include an Ultra High Reliability (UHR) operation element. The UHR operation element may include the Initial NPCA QSRC field.
[0352] The above NPCA primary channel may be a non-primary channel (a channel other than the BSS primary channel) capable of performing backoff while a basic NAV (Network Allocation Vector) is set on the above BSS primary channel. The above basic NAV may be set by OBSS (Overlapping Basic Service Set) traffic. That is, through NPCA, STAs within the BSS (or NPCA STAs) may switch to an alternate channel during the period when OBSS activity is detected in part of the BSS operating channel.
[0353] That is, the present embodiment proposes a method for performing backoff for the NPCA primary channel by newly defining and signaling information related to the CW value of the NPCA primary channel, and selecting a backoff value within the minimum CW value that matches the NPCA primary channel state.
[0354] By newly defining and signaling information related to CW values set to reflect the congestion status or traffic load of the NPCA primary channel, the NPCA STA (NPCA non-AP STA or NPCA AP) can select a backoff value within the minimum CW value (CWmin) suitable for the state of the NPCA primary channel. Accordingly, the NPCA STA can perform the backoff procedure for the NPCA primary channel in a form optimized for the channel environment, and as a result, it has the effect of reducing the probability of collisions caused by media access contention and improving the utilization efficiency of the NPCA primary channel. In addition, by differentially adjusting the CW value according to the channel state, fairness in media access among NPCA STAs can be ensured, and traffic imbalance between the NPCA channel and the BSS primary channel can be mitigated, thereby improving the transmission delay and throughput performance of the overall BSS.
[0355] According to the NPCA operation procedure of the present specification, even when interference is present in the BSS primary channel in an OBSS environment, the NPCA STA has the effect of maintaining stable communication by switching to the NPCA primary channel. Accordingly, the NPCA STA can prevent data transmission from being interrupted by interference and can improve the spectrum utilization efficiency and transmission reliability of the entire BSS.
[0356] <Device Configuration>
[0357] The technical features of the present specification described above may be applied to various devices and methods. For example, the technical features of the present specification described above may be performed / supported through the device of FIG. 1 and / or FIG. 14. For example, the technical features of the present specification described above may be applied only to parts of FIG. 1 and / or FIG. 14. For example, the technical features of the present specification described above may be implemented based on the processing chip (114, 124) of FIG. 1, or based on the processor (111, 121) and memory (112, 122) of FIG. 1, or based on the processor (610) and memory (620) of FIG. 14. For example, the device of the present specification receives a management frame from a Non-primary channel access (NPCA) access point (AP); and performs backoff on the NPCA primary channel based on the management frame.
[0358] The technical features of this specification may be implemented based on a computer-readable medium (CRM). For example, the CRM proposed by this specification is at least one computer-readable medium comprising instructions based on execution by at least one processor.
[0359] The above CRM may store instructions for performing operations including the step of receiving a management frame from an NPCA (Non-primary channel access) AP (access point); and the step of performing backoff on an NPCA primary channel based on the management frame. Instructions stored in the CRM of this specification may be executed by at least one processor. At least one processor associated with the CRM of this specification may be the processor (111, 121) or processing chip (114, 124) of FIG. 1, or the processor (610) of FIG. 14. Meanwhile, the CRM of this specification may be the memory (112, 122) of FIG. 1, the memory (620) of FIG. 14, or a separate external memory / storage medium / disk, etc.
[0360] The technical features of the present specification described above are applicable to various applications or business models. For example, the technical features described above may be applied for wireless communication in devices supporting Artificial Intelligence (AI).
[0361] Artificial intelligence refers to the field of researching artificial intelligence or the methodologies to create it, while machine learning refers to the field of researching methodologies to define and solve various problems addressed within the field of artificial intelligence. Machine learning is also defined as an algorithm that improves performance on a task through continuous experience.
[0362] An Artificial Neural Network (ANN) is a model used in machine learning that can refer to any model capable of problem-solving, composed of artificial neurons (nodes) that form a network through the connection of synapses. An artificial neural network can be defined by connection patterns between neurons in different layers, a learning process that updates model parameters, and an activation function that generates output values.
[0363] An artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer may include one or more neurons, and the artificial neural network may include synapses connecting the neurons. In an artificial neural network, each neuron may output a function value of an activation function for input signals, weights, and biases input through the synapses.
[0364] Model parameters refer to parameters determined through learning, including synaptic connection weights and neuron biases. Hyperparameters, on the other hand, refer to parameters that must be set prior to training in a machine learning algorithm, including the learning rate, number of iterations, mini-batch size, and initialization function.
[0365] The objective of training an artificial neural network can be viewed as determining model parameters that minimize the loss function. The loss function can be used as an indicator to determine optimal model parameters during the training process of an artificial neural network.
[0366] Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning depending on the learning method.
[0367] Supervised learning refers to a method of training an artificial neural network with labels provided for the training data; a label can refer to the correct answer (or result) that the neural network must infer when the training data is input. Unsupervised learning refers to a method of training an artificial neural network without labels provided for the training data. Reinforcement learning refers to a learning method in which an agent defined within an environment is trained to select an action or sequence of actions that maximizes the cumulative reward in each state.
[0368] Machine learning implemented using a Deep Neural Network (DNN) that includes multiple hidden layers among artificial neural networks is also called Deep Learning, and Deep Learning is a part of Machine Learning. Hereinafter, Machine Learning is used in a sense that includes Deep Learning.
[0369] In addition, the aforementioned technical features can be applied to the wireless communication of robots.
[0370] A robot can refer to a machine that automatically processes or operates a given task based on its own capabilities. In particular, a robot that has the ability to perceive its environment, make decisions on its own, and perform actions can be called an intelligent robot.
[0371] Robots can be classified into industrial, medical, domestic, and military types depending on their purpose or field of use. Robots are equipped with drive units, including actuators or motors, to perform various physical movements, such as moving robot joints. Additionally, mobile robots include wheels, brakes, and propellers in their drive units, enabling them to drive on the ground or fly in the air.
[0372] In addition, the aforementioned technical features can be applied to devices that support augmented reality.
[0373] Extended Reality is a collective term for Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR). VR technology provides real-world objects or backgrounds solely as CG images, AR technology provides virtual CG images superimposed on real-world images, and MR technology is a computer graphics technology that mixes and combines virtual objects with the real world.
[0374] MR technology is similar to AR technology in that it displays real-world objects and virtual objects together. However, there is a difference in that while virtual objects in AR technology are used to complement real-world objects, virtual objects and real-world objects are used as equals in MR technology.
[0375] XR technology can be applied to HMDs (Head-Mount Displays), HUDs (Head-Up Displays), mobile phones, tablet PCs, laptops, desktops, TVs, digital signage, etc., and devices to which XR technology is applied can be called XR devices.
[0376] The claims described in this specification may be combined in various ways. For example, the technical features of the method claims in this specification may be combined to be implemented as a device, and the technical features of the device claims in this specification may be combined to be implemented as a method. Furthermore, the technical features of the method claims and the technical features of the device claims in this specification may be combined to be implemented as a device, and the technical features of the method claims and the technical features of the device claims in this specification may be combined to be implemented as a method.
Claims
In wireless LAN systems, A step in which an NPCA (Non-primary channel access) non-AP (non-access point) STA (station) receives a management frame from an NPCA AP; and The above NPCA non-AP STA includes the step of performing backoff for the NPCA primary channel based on the management frame, wherein The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field, and The above Initial NPCA QSRC field includes information regarding a first value used to initialize a first CW (Contention Window) parameter for the above NPCA primary channel, and The first CW parameter is initialized based on the first value and the CW minimum value for the BSS (Basic Service Set) primary channel. method. In paragraph 1, Based on the fact that the backoff value performed for the above NPCA primary channel is 0, The step of the above NPCA non-AP STA transmitting an ICF (Initial Control Frame) to the above NPCA AP; and The above NPCA non-AP STA further includes the step of receiving an ICR (Initial Control Response) frame from the NPCA AP, wherein The value of the backoff performed for the above NPCA primary channel is selected based on the above initialized first CW parameter method. In paragraph 1, The above first CW parameter is initialized to 2^Init_QSRC_NPCA x (CWmin[AC]+1)-1, and The above Init_QSRC_NPCA is associated with the above first value, and The above CWmin[AC] is related to the CW minimum value for the above BSS primary channel method. In paragraph 3, The above management frame further includes an EDCA (Enhanced Distributed Channel Access) parameter set element for the above BSS primary channel, and The above EDCA parameter setting element includes information regarding the CW minimum value for the above BSS primary channel, and The CW minimum value for the above BSS primary channel is stored in the above NPCA non-AP STA method. In paragraph 1, The above Initial NPCA QSRC field is set to 4 bits, and Based on the fact that the above Initial NPCA QSRC field is 0, the above first CW parameter uses the CW minimum value for the BSS primary channel as is, and Based on the fact that the Initial NPCA QSRC field is 1, the first CW parameter is initialized to half the value of the CW minimum value for the BSS primary channel, and Based on the fact that the above Initial NPCA QSRC field is 2, the above first CW parameter is initialized to a value twice the CW minimum value for the above BSS primary channel, and Based on the fact that the above Initial NPCA QSRC field is 3, the above first CW parameter is initialized to the CW minimum value for the BSS primary channel. method. In paragraph 1, The above management frame is a beacon frame, a probe response frame, or a linked response frame, and The above beacon frame, the above probe response frame, or the above linkage response frame includes an Ultra High Reliability (UHR) operation element, and The above UHR operation element includes the Initial NPCA QSRC field. method. In a wireless LAN system, an NPCA (Non-primary channel access) non-AP (non-access point) STA (station) is, Memory; transceiver; and The processor comprises the memory and the transceiver, operably coupled thereto, wherein the processor comprises: Receive a management frame from the NPCA AP (access point); and Perform backoff for the NPCA primary channel based on the above management frame, but, The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field, and The above Initial NPCA QSRC field includes information regarding a first value used to initialize a first CW (Contention Window) parameter for the above NPCA primary channel, and The first CW parameter is initialized based on the first value and the CW minimum value for the BSS (Basic Service Set) primary channel. NPCA non-AP STA. In wireless LAN systems, A step in which an NPCA (Non-primary channel access) AP (access point) transmits a management frame to an NPCA non-AP STA (station); and The above NPCA AP includes the step of performing backoff for the NPCA primary channel based on the management frame, wherein Perform backoff for the NPCA primary channel based on the above management frame, but, The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field, and The above Initial NPCA QSRC field includes information regarding a first value used to initialize a first CW (Contention Window) parameter for the above NPCA primary channel, and The first CW parameter is initialized based on the first value and the CW minimum value for the BSS (Basic Service Set) primary channel. method. In paragraph 8, Based on the fact that the backoff value performed for the above NPCA primary channel is 0, The step of the NPCA AP receiving an ICF (Initial Control Frame) from the NPCA non-AP STA; and The above NPCA AP further includes the step of transmitting an ICR (Initial Control Response) frame to the above NPCA non-AP STA, wherein The value of the backoff performed for the above NPCA primary channel is selected based on the above initialized first CW parameter method. In paragraph 8, The above first CW parameter is initialized to 2^Init_QSRC_NPCA x (CWmin[AC]+1)-1, and The above Init_QSRC_NPCA is associated with the above first value, and The above CWmin[AC] is related to the CW minimum value for the above BSS primary channel method. In Paragraph 10, The above management frame further includes an EDCA (Enhanced Distributed Channel Access) parameter set element for the above BSS primary channel, and The above EDCA parameter setting element includes information regarding the CW minimum value for the above BSS primary channel, and The CW minimum value for the above BSS primary channel is stored in the above NPCA non-AP STA method. In paragraph 8, The above Initial NPCA QSRC field is set to 4 bits, and Based on the fact that the above Initial NPCA QSRC field is 0, the above first CW parameter uses the CW minimum value for the BSS primary channel as is, and Based on the fact that the Initial NPCA QSRC field is 1, the first CW parameter is initialized to half the value of the CW minimum value for the BSS primary channel, and Based on the fact that the above Initial NPCA QSRC field is 2, the above first CW parameter is initialized to a value twice the CW minimum value for the above BSS primary channel, and Based on the fact that the above Initial NPCA QSRC field is 3, the above first CW parameter is initialized to the CW minimum value for the BSS primary channel. method. In paragraph 8, The above management frame is a beacon frame, a probe response frame, or a linked response frame, and The above beacon frame, the above probe response frame, or the above linkage response frame includes an Ultra High Reliability (UHR) operation element, and The above UHR operation element includes the Initial NPCA QSRC field. method. In a wireless LAN system, an NPCA (Non-primary channel access) AP (access point) is, Memory; transceiver; and The processor comprises the memory and the transceiver, operably coupled thereto, wherein the processor comprises: Transmit a management frame to an NPCA non-AP STA(station); and Perform backoff for the NPCA primary channel based on the above management frame, but, Perform backoff for the NPCA primary channel based on the above management frame, but, The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field, and The above Initial NPCA QSRC field includes information regarding a first value used to initialize a first CW (Contention Window) parameter for the above NPCA primary channel, and The first CW parameter is initialized based on the first value and the CW minimum value for the BSS (Basic Service Set) primary channel. NPCA AP. In at least one computer-readable medium comprising an instruction based on execution by at least one processor, A step of receiving a management frame from an NPCA (Non-primary channel access) AP (access point); and The method includes the step of performing backoff on the NPCA primary channel based on the above management frame, wherein The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field, and The above Initial NPCA QSRC field includes information regarding a first value used to initialize a first CW (Contention Window) parameter for the above NPCA primary channel, and The first CW parameter is initialized based on the first value and the CW minimum value for the BSS (Basic Service Set) primary channel. Recording media. In a device in a wireless LAN system, Memory; and The processor comprises the above memory and operablely coupled thereto, wherein the processor is: Receive a management frame from an NPCA (Non-primary channel access) AP (access point); and Perform backoff for the NPCA primary channel based on the above management frame, but, The above management frame includes an Initial NPCA QSRC (Queue Size Randomization Control) field, and The above Initial NPCA QSRC field includes information regarding a first value used to initialize a first CW (Contention Window) parameter for the above NPCA primary channel, and The first CW parameter is initialized based on the first value and the CW minimum value for the BSS (Basic Service Set) primary channel. device.