Transmission of link capability information

Abstract

The present invention relates to a method performed by a non-access point (AP) station (STA) multi-link device (MLD) of a wireless LAN system, the method comprising the following steps: sending a negotiation frame including first maximum number of spatial streams (NSS) information to an AP MLD via a first link; and receiving a negotiation response frame from the AP MLD via the first link.

Description

Technical Field

[0001] The present specification relates to a method of transmitting information about a maximum number of flows of a link in a wireless local area network (WLAN) system. Background Art

[0002] Wireless network technology may include various types of wireless local area networks (WLANs). WLANs use widely used networking protocols and can be used to interconnect nearby devices. The various technical features described herein can be applied to any communication standard such as WiFi, or more generally, any one of the IEEE 802.11 series of wireless protocols. Wireless local area networks (WLANs) have been enhanced in various ways. For example, the IEEE 802.11ax standard proposes an enhanced communication environment using orthogonal frequency division multiple access (OFDMA) and downlink multi-user multiple input multiple output (DL MU MIMO) schemes.

[0003] This specification proposes technical features that can be used in new communication standards. For example, the new communication standard may be the extremely high throughput (EHT) standard currently under discussion. The EHT standard may use newly proposed increased bandwidth, enhanced PHY layer protocol data unit (PPDU) structure, enhanced sequence, hybrid automatic repeat request (HARQ) scheme, etc. The EHT standard may be referred to as the IEEE 802.11be standard. Summary of the invention

[0004] Technical Solution

[0005] A method performed by a transmitting device in a wireless local area network (WLAN) system according to various embodiments may include technical features related to a method of transmitting information about a maximum number of streams. In the method performed in a non-access point (AP) station (STA) multi-link device (MLD) of the WLAN system, the non-AP STA MLD may transmit a negotiation frame including first maximum number of spatial streams (NSS) information to the AP MLD via a first link. The non-AP STA MLD may receive a negotiation response frame in response to the negotiation frame from the AP MLD via the first link.

[0006] Beneficial Effects

[0007] According to an example of the present specification, the maximum NSS capability information is transmitted / received to obtain an advantage of preventing a problem in which the MLD cannot receive all flows because flows having at least NSS capability are transmitted on a specific link. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 An example of a transmitting device and / or a receiving device of the present specification is shown.

[0009] Figure 2is a conceptual diagram showing the structure of a wireless local area network (WLAN).

[0010] Figure 3 A general link establishment process is shown.

[0011] Figure 4 An example of PPDU used in the IEEE standard is shown.

[0012] Figure 5 The layout of resource units (RUs) used in a frequency band of 20 MHz is shown.

[0013] Figure 6 The layout of RUs used in a frequency band of 40 MHz is shown.

[0014] Figure 7 The layout of RUs used in the 80 MHz frequency band is shown.

[0015] Figure 8 The structure of the HE-SIG-B field is shown.

[0016] Fig. 9 An example is shown in which multiple user STAs are assigned to the same RU through the MU-MIMO scheme.

[0017] Fig.10 The operation based on UL-MU is shown.

[0018] Fig.11 An example of a trigger frame is shown.

[0019] Fig.12 An example of a common information field of a trigger frame is shown.

[0020] Fig.13 An example of subfields included in the per-user information field is shown.

[0021] Fig.14 The technical features of the UORA scheme are described.

[0022] Fig.15 An example of channels used / supported / defined within the 2.4 GHz band is shown.

[0023] Fig.16 An example of channels used / supported / defined within the 5 GHz band is shown.

[0024] Fig.17 An example of channels used / supported / defined within the 6 GHz band is shown.

[0025] Fig.18 An example of PPDU used in this specification is shown.

[0026] Fig.19An example of a modified transmitting device and / or receiving device of the present specification is shown.

[0027] Fig. 20 An example of channel bonding is shown.

[0028] Fig.21 An example of the VHT operation element format is shown.

[0029] Fig. 22 An example of a multilink element format is shown.

[0030] Fig.23 An implementation of U-SIG is shown.

[0031] Fig.24 and Fig.25 An embodiment of an operating band negotiation request frame format is shown.

[0032] Fig.26 An embodiment of an operating band negotiation response frame format is shown.

[0033] Fig. 27 An implementation of the EHT Capability Element format is shown.

[0034] Fig.28 is a flow chart illustrating an example of an operating band switching process.

[0035] Fig.29 An example of an operating band switching process is shown.

[0036] Fig.30 is a flow chart illustrating another example of an operating band switching process.

[0037] Fig.31 Another example of an operating band switching process is shown.

[0038] Fig.32 An implementation of a frequency band switch announcement element is shown.

[0039] Fig.33 An implementation of a frequency band switch announcement element is shown.

[0040] Fig.34 An implementation of a frequency band switching process is shown.

[0041] Fig.35 An embodiment of the method performed in a non-AP (Access Point) STA (Station) MLD (Multi-Link Device) is shown.

[0042] Fig.36 An embodiment of a method performed in an AP MLD is shown. DETAILED DESCRIPTION

[0043] In this specification, "A or B" may mean "only A", "only B", or "both A and B". In other words, 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".

[0044] A slash ( / ) or a comma used in this specification may represent "and / or". For example, "A / B" may represent "A and / or B". Thus, "A / B" may represent "only A", "only B", or "both A and B". For example, "A, B, C" may represent "A, B, or C".

[0045] In the present specification, "at least one of A and B" may mean "only A", "only B", or "both A and B". In addition, in the present specification, the expression "at least one of A or B" or "at least one of A and / or B" may be interpreted as "at least one of A and B".

[0046] In addition, in the present specification, "at least one of A, B, and C" may mean "only A", "only B", "only C", or "any combination of A, B, and C". In addition, "at least one of A, B, or C" or "at least one of A, B and / or C" may mean "at least one of A, B, and C".

[0047] In addition, the brackets used in this specification may mean "for example". Specifically, when indicated as "control information (EHT-signal)", it may mean that "EHT-signal" is proposed as an example of "control information". In other words, the "control information" of this specification is not limited to "EHT-signal", and "EHT-signal" may be proposed as an example of "control information". In addition, when indicated as "control information (ie, EHT signal)", it may also mean that "EHT signal" is proposed as an example of "control information".

[0048] Technical features described separately in one drawing of the present specification may be implemented separately or simultaneously.

[0049] The following examples of this specification can be applied to various wireless communication systems. For example, the following examples of this specification can be applied to wireless local area network (WLAN) systems. For example, this specification can be applied to IEEE 802.11a / g / n / ac standards or IEEE802.11ax standards. In addition, this specification can also be applied to the newly proposed EHT standard or IEEE 802.11be standard. In addition, the examples of this specification can also be applied to new WLAN standards enhanced from the EHT standard or the IEEE 802.11be standard. In addition, the examples of this specification can be applied to mobile communication systems. For example, it can be applied to long-term evolution (LTE) based on the 3rd Generation Partnership Project (3GPP) standard and mobile communication systems based on the evolution of LTE. In addition, the examples of this specification can be applied to communication systems based on the 5G NR standard of the 3GPP standard.

[0050] Hereinafter, in order to describe the technical features of the present specification, technical features applicable to the present specification will be described.

[0051] Figure 1 An example of a transmitting device and / or a receiving device of the present specification is shown.

[0052] exist Figure 1 In the example of , various technical features described below can be performed. Figure 1 At least one station (STA) is involved. For example, the STAs 110 and 120 of this specification may also be referred to as various terms such as mobile terminals, wireless devices, wireless transmit / receive units (WTRUs), user equipment (UEs), mobile stations (MSs), mobile subscriber units, or simply users. The STAs 110 and 120 of this specification may also be referred to as various terms such as networks, base stations, node Bs, access points (APs), repeaters, routers, repeaters, etc. The STAs 110 and 120 of this specification may also be referred to as various names such as receiving devices, transmitting devices, receiving STAs, transmitting STAs, receiving devices, transmitting devices, etc.

[0053] For example, the STAs 110 and 120 may function as an AP or a non-AP. That is, the STAs 110 and 120 of the present specification may function as an AP and / or a non-AP.

[0054] In addition to the IEEE 802.11 standard, the STAs 110 and 120 of the present specification may support various communication standards together. For example, communication standards based on 3GPP standards (e.g., LTE, LTE-A, 5G NR standards), etc. may be supported. In addition, the STAs of the present specification may be implemented as various devices such as mobile phones, vehicles, personal computers, etc. In addition, the STAs of the present specification may support communication for various communication services such as voice calls, video calls, data communications, and self-driving (autonomous driving).

[0055] The STAs 110 and 120 of the present specification may include a medium access control (MAC) conforming to the IEEE 802.11 standard and a physical layer interface for a radio medium.

[0056] The following will refer to Figure 1 Sub-figure (a) of FIG. 1 describes STAs 110 and 120 .

[0057] The first STA 110 may include a processor 111, a memory 112, and a transceiver 113. The processor, memory, and transceiver shown may be individually implemented as separate chips, or at least two blocks / functions may be implemented by a single chip.

[0058] The transceiver 113 of the first STA performs a signal transmission / reception operation. Specifically, it can transmit / receive IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.).

[0059] For example, the first STA 110 may perform operations expected by the AP. For example, the processor 111 of the AP may receive a signal through the transceiver 113, process a received (RX) signal, generate a transmitted (TX) signal, and provide control for signal transmission. The memory 112 of the AP may store a signal (e.g., an RX signal) received through the transceiver 113, and may store a signal (e.g., a TX signal) to be sent through the transceiver.

[0060] For example, the second STA 120 may perform operations expected by the non-AP STA. For example, the transceiver 123 of the non-AP performs signal transmission / reception operations. Specifically, IEEE 802.11 packets (e.g., IEEE 802.11a / b / g / n / ac / ax / be packets, etc.) may be transmitted / received.

[0061] For example, the processor 121 of the non-AP STA may receive a signal through the transceiver 123, process the RX signal, generate a TX signal, and provide control for signal transmission. The memory 122 of the non-AP STA may store a signal (e.g., an RX signal) received through the transceiver 123, and may store a signal (e.g., a TX signal) to be transmitted through the transceiver.

[0062] For example, the operation of a device indicated as an AP in the specification described below may be performed in the first STA 110 or the second STA 120. For example, if the first STA 110 is an AP, the operation of the device indicated as the AP may be controlled by the processor 111 of the first STA 110, and the relevant signal may be transmitted or received through the transceiver 113 controlled by the processor 111 of the first STA 110. In addition, control information related to the operation of the AP or the TX / RX signal of the AP may be stored in the memory 112 of the first STA 110. In addition, if the second STA 120 is an AP, the operation of the device indicated as the AP may be controlled by the processor 121 of the second STA 120, and the relevant signal may be transmitted or received through the 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 TX / RX signal of the AP may be stored in the memory 122 of the second STA 120.

[0063] For example, in the specification described below, the operation of the device indicated as a non-AP (or user STA) may be performed in the first STA 110 or the second STA 120. For example, if the second STA 120 is a non-AP, the operation of the device indicated as the non-AP may be controlled by the processor 121 of the second STA 120, and the relevant signal may be transmitted or received through the transceiver 123 controlled by the processor 121 of the second STA 120. In addition, control information related to the operation of the non-AP or the TX / RX signal of the non-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 indicated as the non-AP may be controlled by the processor 111 of the first STA 110, and the relevant signal may be transmitted or received through the transceiver 113 controlled by the processor 111 of the first STA 110. In addition, control information related to the operation of the non-AP or the TX / RX signal of the non-AP may be stored in the memory 112 of the first STA 110.

[0064] In the specification described below, devices referred to as (transmitting / receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting / receiving) terminal, (transmitting / receiving) device, (transmitting / receiving) equipment, network, etc. may refer to Figure 1 For example, a device indicated as (but not specifically numbered) (transmitting / receiving) STA, a first STA, a second STA, STA1, STA2, AP, a first AP, a second AP, AP1, AP2, a (transmitting / receiving) terminal, a (transmitting / receiving) device, a (transmitting / receiving) apparatus, a network, etc. may refer to Figure 1For example, in the following example, the operation of various STAs sending / receiving signals (eg, PPDU) may be performed in Figure 1 In addition, in the following examples, various STAs generate TX / RX signals or perform data processing and calculations in advance for TX / RX signals. Figure 1 111 and 121 of the processors. For example, examples of operations for generating TX / RX signals or performing data processing and calculation in advance may include: 1) operations for determining / obtaining / configuring / calculating / decoding / encoding bit information of subfields (SIG, STF, LTF, Data) included in the PPDU; 2) operations for determining / configuring / obtaining time resources or frequency resources (e.g., subcarrier resources) for subfields (SIG, STF, LTF, Data) included in the PPDU; 3) operations for determining / configuring / obtaining specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for subfields (SIG, STF, LTF, Data) included in the PPDU; 4) power control operations and / or power saving operations applied to STAs; and 5) operations related to determining / obtaining / configuring / decoding / encoding of ACK signals, etc. In addition, in the following examples, various information (e.g., information related to fields / subfields / control fields / parameters / power, etc.) used by various STAs to determine / obtain / configure / calculate / decode / encode TX / RX signals may be stored in Figure 1 in the memories 112 and 122.

[0065] Figure 1 The aforementioned device / STA of sub-graph (a) can be as follows Figure 1 In the following, we will modify the Figure 1 Sub-figure (b) of FIG. 1 is used to describe STA 110 and STA 120 of the present specification.

[0066] For example, Figure 1 The transceivers 113 and 123 shown in the sub-diagram (b) of FIG. Figure 1 The same functions as the aforementioned transceiver shown in sub-figure (a) of FIG. Figure 1 The processing chips 114 and 124 shown in sub-figure (b) may include processors 111 and 121 and memories 112 and 122 . Figure 1 The processors 111 and 121 and the memories 112 and 122 shown in the sub-diagram (b) of FIG. Figure 1 The processors 111 and 121 and memories 112 and 122 have the same functions as those shown in sub-figure (a) above.

[0067] 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, access point (AP), repeater, router, repeater, receiving unit, sending unit, receiving STA, sending STA, receiving device, sending device, receiving apparatus and / or sending apparatus described below may mean Figure 1 STAs 110 and 120 shown in sub-figures (a) / (b) of Figure 1 The processing chips 114 and 124 shown in the sub-figure (b) of FIG. That is, the technical features of this specification can be Figure 1 The STA 110 and 120 shown in the sub-figure (a) / (b) of FIG. 110 and 120 may be executed only in Figure 1 The processing chips 114 and 124 shown in the sub-figure (b) of Figure 1 For example, the technical feature of sending a control signal from a STA can be understood as the transceiver 113 and 123 shown in the sub-figure (a) / (b) of FIG. Figure 1 The transceiver 113 shown in the sub-figure (a) / (b) of FIG. Figure 1 The technical features of the control signals generated in the processors 111 and 121 illustrated in the sub-figures (a) / (b) of FIG. Alternatively, the technical features of the STA sending the control signal can be understood as Figure 1 The technical features of the processing chips 114 and 124 shown in the sub-figure (b) of FIG. 10 are for generating control signals to be transmitted to the transceivers 113 and 123 .

[0068] For example, the technical feature of receiving the control signal by the receiving STA can be understood as Figure 1 The technical feature of the transceivers 113 and 123 receiving the control signal shown in the sub-figure (a) of FIG. 1 can be understood as the technical feature of the receiving STA receiving the control signal through Figure 1 The processors 111 and 121 shown in the sub-diagram (a) of Figure 1 The technical features of the control signal received by the transceivers 113 and 123 shown in the sub-figure (a) of FIG. Alternatively, the technical features of the receiving STA receiving the control signal can be understood as Figure 1 The processing chips 114 and 124 shown in the sub-figure (b) of Figure 1 Technical characteristics of the control signals received in transceivers 113 and 123 shown in sub-figure (b).

[0069] Reference Figure 1As shown in sub-figure (b), software codes 115 and 125 may be included in memories 112 and 122. Software codes 115 and 126 may include instructions for controlling operations of processors 111 and 121. Software codes 115 and 125 may be included as various programming languages.

[0070] Figure 1 The processors 111 and 121 or the processing chips 114 and 124 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, Figure 1 The processors 111 and 121 or the processing chips 114 and 124 may include at least one of the following: a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modulator and demodulator (modem). Figure 1 The processors 111 and 121 or the processing chips 114 and 124 may be composed of The SNAPDRAGONTM processor series manufactured by EXYNOSTM processor series manufactured by Processor family manufactured by The HELIOTM processor series manufactured by The ATOMTM processor family manufactured by or enhanced from these processors.

[0071] In this specification, uplink may mean a link for communication from a non-AP STA to an SP STA, and an uplink PPDU / packet / signal, etc. may be transmitted through the uplink. In addition, in this specification, downlink may mean a link for communication from an AP STA to a non-AP STA, and a downlink PPDU / packet / signal, etc. may be transmitted through the downlink.

[0072] Figure 2 is a conceptual diagram showing the structure of a wireless local area network (WLAN).

[0073] Figure 2 The upper part of shows the structure of an infrastructure basic service set (BSS) of the Institute of Electrical and Electronics Engineers (IEEE) 802.11.

[0074] Reference Figure 2The wireless LAN system may include one or more infrastructure BSSs 200 and 205 (hereinafter, referred to as BSSs). BSSs 200 and 205, which are a collection of APs and STAs (e.g., access point (AP) 225 and station (STA1) 200-1) that are successfully synchronized to communicate with each other, are not concepts indicating a specific area. BSS 205 may include one or more STAs 205-1 and 205-2 that may join one AP 230.

[0075] The BSS may include at least one STA, an AP providing a distributed service, and a distribution system (DS) 210 connecting a plurality of APs.

[0076] The distribution system 210 may implement an extended service set (ESS) 240 extended by connecting a plurality of BSSs 200 and 205. The ESS 240 may be used as a term indicating one network configured by connecting one or more APs 225 or 230 via the distribution system 210. APs included in one ESS 240 may have the same service set identification (SSID).

[0077] The portal 220 may serve as a bridge connecting a wireless LAN network (IEEE 802.11) and another network (eg, 802.X).

[0078] exist Figure 2 In the BSS shown in the upper part of FIG, a network between the APs 225 and 230 and a network between the APs 225 and 230 and the STAs 200-1, 205-1, and 205-2 can be implemented. However, a network is configured between the STAs to perform communication even without the APs 225 and 230. A network that performs communication by configuring a network between the STAs even without the APs 225 and 230 is defined as an ad hoc network or an independent basic service set (IBSS).

[0079] Figure 2 The lower part of FIG. 1 shows a conceptual diagram illustrating an IBSS.

[0080] Reference Figure 2 In the lower part, the IBSS is a BSS operating in a self-organizing mode. Since the IBSS does not include an access point (AP), there is no centralized management entity that performs management functions in the center. That is, in the IBSS, STAs 250-1, 250-2, 250-3, 255-4, and 255-5 are managed in a distributed manner. In the IBSS, all STAs 250-1, 250-2, 250-3, 255-4, and 255-5 may be composed of mobile STAs, and access to the DS is not allowed to form a self-contained network.

[0081] Figure 3A general link establishment process is shown.

[0082] In S310, the STA may perform a network discovery operation. The network discovery operation may include a scanning operation of the STA. That is, in order to access the network, the STA needs to discover participating networks. The STA needs to identify compatible networks before joining a wireless network, and the process of identifying a network present in a specific area is called scanning. Scanning methods include active scanning and passive scanning.

[0083] Figure 3 A network discovery operation including an active scanning process is shown. In active scanning, the STA performing the scan sends a probe request frame and waits for a response to the probe request frame in order to identify which AP is around while moving to the channel. The responder sends a probe response frame to the STA that has sent the probe request frame as a response to the probe request frame. Here, the responder may be the STA that sent the last beacon frame in the BSS of the channel being scanned. In the BSS, since the AP sends a beacon frame, the AP is the responder. In the IBSS, since the STAs in the IBSS take turns sending beacon frames, the responder is not fixed. For example, when the STA sends a probe request frame via channel 1 and receives a probe response frame via channel 1, the STA may store the BSS-related information included in the received probe response frame, may move to the next channel (e.g., channel 2), and may perform scanning by the same method (e.g., sending a probe request and receiving a probe response via channel 2).

[0084] although Figure 3 Not shown in the figure, scanning can be performed by a passive scanning method. In passive scanning, the STA performing the scan can wait for a beacon frame while moving to a channel. The beacon frame is one of the management frames in IEEE 802.11, and is periodically sent to indicate the existence of a wireless network and enable the STA performing the scan to find the wireless network and join the wireless network. In the BSS, the AP is used to periodically send beacon frames. In the IBSS, the STAs in the IBSS take turns sending beacon frames. Upon receiving the beacon frame, the STA performing the scan stores information related to the BSS included in the beacon frame and records the beacon frame information in each channel while moving to another channel. The STA that receives the beacon frame can store the BSS-related information included in the received beacon frame, can move to the next channel, and can perform scanning in the next channel by the same method.

[0085] After discovering the network, the STA may perform an authentication process in S320. This authentication process may be referred to as a first authentication process to clearly distinguish it from the security establishment operation in the subsequent S340. The authentication process in S320 may include a process in which the STA sends an authentication request frame to the AP and the AP sends an authentication response frame to the STA in response. The authentication frame used for the authentication request / response is a management frame.

[0086] The authentication frame may include information related to an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a robust security network (RSN), and a limited cycle group.

[0087] The STA may send an authentication request frame to the AP. The AP may determine whether to allow authentication of the STA based on information included in the received authentication request frame. The AP may provide the STA with an authentication process result via an authentication response frame.

[0088] When the STA is successfully authenticated, the STA may perform an association process in S330. The association process includes a process in which the STA sends an association request frame to the AP and the AP sends an association response frame to the STA in response. For example, the association request frame may include information related to various capabilities, a beacon listening interval, a service set identifier (SSID), supported rates, supported channels, RSN, a mobile domain, a supported operation category, a traffic indication map (TIM) broadcast request, and interworking service capabilities. For example, the association response frame may include information related to various capabilities, a status code, an association ID (AID), supported rates, an enhanced distributed channel access (EDCA) parameter set, a received channel power indicator (RCPI), a received signal-to-noise ratio indicator (RSNI), a mobile domain, a timeout interval (association recovery time), overlapping BSS scanning parameters, a TIM broadcast response, and a QoS map.

[0089] In S340, the STA may perform a security establishment process. The security establishment process in S340 may include a process of establishing a private key through a four-way handshake (eg, through an Extensible Authentication Protocol over LAN (EAPOL) frame).

[0090] Figure 4 An example of PPDU used in the IEEE standard is shown.

[0091] As shown, various types of PHY protocol data units (PPDUs) are used in the IEEE a / g / n / ac standards. Specifically, LTF and STF include training signals, SIG-A and SIG-B include control information for receiving STAs, and the data field includes user data corresponding to PSDU (MAC PDU / aggregated MAC PDU).

[0092] Figure 4An example of a HE PPDU according to IEEE 802.11ax is also shown. Figure 4 The HE PPDU is an exemplary PPDU for multiple users. The HE-SIG-B may be included only in the PPDU for multiple users, and the HE-SIG-B may be omitted in the PPDU for a single user.

[0093] like Figure 4 As shown, the HE-PPDU for multiple users (MU) may include a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signal (L-SIG), a high efficiency signal A (HE-SIG A), a high efficiency signal B (HE-SIG B), a high efficiency short training field (HE-STF), a high efficiency long training field (HE-LTF), a data field (alternatively, a MAC payload), and a packet extension (PE) field. Each field may be sent within the time period shown (i.e., 4 or 8 μs).

[0094] The following describes a resource unit (RU) for a PPDU. A RU may include multiple subcarriers (or tones). A RU may be used to send signals to multiple STAs according to OFDMA. In addition, a RU may also be defined as sending a signal to one STA. A RU may be used for an STF, an LTF, a data field, etc.

[0095] Figure 5 The layout of resource units (RUs) used in a frequency band of 20 MHz is shown.

[0096] like Figure 5 As shown, resource units (RUs) corresponding to different numbers of tones (i.e., subcarriers) may be used to form some fields of the HE-PPDU. For example, resources may be allocated for the HE-STF, HE-LTF, and data fields in the RU shown.

[0097] like Figure 5 As shown in the uppermost part of , 26 units (i.e., units corresponding to 26 tones) may be set. Six tones may be used for a guard band in the leftmost band of the 20 MHz band, and five tones may be used for a guard band in the rightmost band of the 20 MHz band. In addition, seven DC tones may be inserted in the center band (i.e., the DC band), and 26 units corresponding to 13 tones on each of the left and right sides of the DC band may be set. 26 units, 52 units, and 106 units may be allocated to other bands. Each unit may be allocated to a receiving STA (i.e., a user).

[0098] Figure 5 The layout of the RU in can be used not only for multiple users (MU) but also for a single user (SU), in which case one 242 unit can be used and three DC tones can be inserted, such as Figure 5as shown at the bottom.

[0099] although Figure 5 RUs of various sizes are proposed, namely, 26-RU, 52-RU, 106-RU, and 242-RU, but RUs of a specific size may be expanded or increased. Therefore, the present embodiment is not limited to a specific size of each RU (ie, the number of corresponding tones).

[0100] Figure 6 The layout of RUs used in a frequency band of 40 MHz is shown.

[0101] Similar to using RUs with various sizes Figure 5 ,exist Figure 6 In the example of 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, etc. can be used. In addition, five DC tones can be inserted in the center frequency, 12 tones can be used for the guard band in the leftmost band of the 40MHz band, and 11 tones can be used for the guard band in the rightmost band of the 40MHz band.

[0102] like Figure 6 As shown in FIG. 4, when the RU layout is used for a single user, 484-RU can be used. The specific number of RUs can be similar to Figure 5 Change.

[0103] Figure 7 The layout of RUs used in the 80 MHz frequency band is shown.

[0104] Similar to using RUs with various sizes Figure 5 and Figure 6 ,exist Figure 7 In the example of 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, 996-RU, etc. can be used. In addition, seven DC tones can be inserted in the center frequency, 12 tones can be used for the guard band in the leftmost band of the 80 MHz band, and 11 tones can be used for the guard band in the rightmost band of the 80 MHz band. In addition, 26-RU corresponding to 13 tones on each side of the left and right sides of the DC band can be used.

[0105] like Figure 7 As shown, when the RU layout is for a single user, the 996-RU can be used, in which case five DC tones can be inserted.

[0106] The RU described in this specification can be used in uplink (UL) communication and downlink (DL) communication. For example, when performing UL-MU communication requested by a trigger frame, the transmitting STA (e.g., AP) can allocate a first RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to the first STA through a trigger frame, and can allocate a second RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to the second STA. Thereafter, the first STA can send a first triggered PPDU based on the first RU, and the second STA can send a second triggered PPDU based on the second RU.

[0107] The first / second trigger-based PPDU is sent to the AP in the same (or overlapping) time period.

[0108] For example, when configuring a DL MU PPDU, the transmitting STA (e.g., AP) may allocate a first RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to the first STA, and may allocate a second RU (e.g., 26 / 52 / 106 / 242-RU, etc.) to the second STA. That is, the transmitting STA (e.g., AP) may transmit the HE-STF, HE-LTF, and Data fields for the first STA through the first RU in one MU PPDU, and may transmit the HE-STF, HE-LTF, and Data fields for the second STA through the second RU.

[0109] Information about the layout of RUs may be signaled via HE-SIG-B.

[0110] Figure 8 The structure of the HE-SIG-B field is shown.

[0111] As shown, the HE-SIG-B field 810 includes a common field 820 and a user-specific field 830. The common field 820 may include information commonly applied to all users (i.e., user STAs) receiving the SIG-B. The user-specific field 830 may be referred to as a user-specific control field. When the SIG-B is transmitted to multiple users, the user-specific field 830 may be applied to only any one of the multiple users.

[0112] like Figure 8 As shown, the common field 820 and the user-specific field 830 may be encoded separately.

[0113] The common field 820 may include N*8 bits of RU allocation information. For example, the RU allocation information may include information related to the location of the RU. For example, when Figure 5 When a 20 MHz channel is used as shown, the RU allocation information may include information about a specific frequency band where a specific RU (26-RU / 52-RU / 106-RU) is arranged.

[0114] An example of the case where the RU allocation information consists of 8 bits is as follows.

[0115] [Table 1]

[0116]

[0117] like Figure 5 As shown in the example of , up to nine 26-RUs can be allocated to a 20 MHz channel. When the RU allocation information of the common field 820 is set to "00000000" as shown in Table 1, nine 26-RUs can be allocated to the corresponding channel (i.e., 20 MHz). In addition, when the RU allocation information of the common field 820 is set to "00000001" as shown in Table 1, seven 26-RUs and one 52-RU are arranged in the corresponding channel. That is, in Figure 5 In the example of , 52-RU can be allocated to the far right, and seven 26-RUs can be allocated to its left.

[0118] The example of Table 1 shows only some RU locations where RU allocation information can be displayed.

[0119] For example, the RU allocation information may include the example in Table 2 below.

[0120] [Table 2]

[0121]

[0122] "01000y2y1y0" relates to an example in which a 106-RU is allocated to the leftmost side of a 20 MHz channel and five 26-RUs are allocated to the right thereof. In this case, multiple STAs (e.g., user STAs) may be allocated to the 106-RU based on the MU-MIMO scheme. Specifically, up to 8 STAs (e.g., user STAs) may be allocated to the 106-RU, and the number of STAs (e.g., user STAs) allocated to the 106-RU is determined based on the 3-bit information (y2y1y0). For example, when the 3-bit information (y2y1y0) is set to N, the number of STAs (e.g., user STAs) allocated to the 106-RU based on the MU-MIMO scheme may be N+1.

[0123] Typically, multiple STAs (eg, user STAs) different from each other may be allocated to multiple RUs. However, multiple STAs (eg, user STAs) may be allocated to one or more RUs having at least a specific size (eg, 106 subcarriers) based on the MU-MIMO scheme.

[0124] like Figure 8As shown, the user-specific field 830 may include multiple user fields. As described above, the number of STAs (e.g., user STAs) assigned to a specific channel may be determined based on the RU allocation information of the common field 820. For example, when the RU allocation information of the common field 820 is "00000000", one user STA may be allocated to each of the nine 26-RUs (e.g., nine user STAs may be allocated). That is, up to 9 user STAs may be allocated to a specific channel through the OFDMA scheme. In other words, up to 9 user STAs may be allocated to a specific channel through a non-MU-MIMO scheme.

[0125] For example, when RU allocation is set to "01000y2y1y0", multiple STAs can be allocated to the 106-RU arranged on the leftmost side through the MU-MIMO scheme, and five user STAs can be allocated to the five 26-RUs arranged on the right side thereof through the non-MU MIMO scheme. Fig. 9 .

[0126] Fig. 9 An example is shown in which multiple user STAs are assigned to the same RU through the MU-MIMO scheme.

[0127] For example, when Fig. 9 When the RU allocation is set to "01000010", the 106-RU may be allocated to the leftmost side of a specific channel, and five 26-RUs may be allocated to the right side thereof. In addition, three user STAs may be allocated to the 106-RU through the MU-MIMO scheme. As a result, since eight user STAs are allocated, the user-specific field 830 of the HE-SIG-B may include eight user fields.

[0128] Eight user fields can be pressed Fig. 9 In addition, Figure 8 As shown, two user fields can be implemented using one user block field.

[0129] Figure 8 and Fig. 9 The user field shown may be configured based on two formats. That is, the user field related to the MU-MIMO scheme may be configured in a first format, and the user field related to the non-MIMO scheme may be configured in a second format. Fig. 9 In the example of , user field 1 to user field 3 may be based on the first format, and user field 4 to user field 8 may be based on the second format. The first format or the second format may include bit information of the same length (eg, 21 bits).

[0130] Each user field may have the same size (eg, 21 bits). For example, the user field of the first format (the first MU-MIMO scheme) may be configured as follows.

[0131] For example, the first bit (i.e., B0-B10) in the user field (i.e., 21 bits) may include identification information (e.g., STA-ID, partial AID, etc.) of the user STA that allocates the corresponding user field. In addition, the second bit (i.e., B11-B14) in the user field (i.e., 21 bits) may include information related to the space configuration. Specifically, examples of the second bit (i.e., B11-B14) may be shown in Tables 3 and 4 below.

[0132] [Table 3]

[0133]

[0134] [Table 4]

[0135]

[0136] As shown in Table 3 and / or Table 4, the second bits (e.g., B11-B14) may include information related to the number of spatial streams allocated to multiple user STAs allocated based on the MU-MIMO scheme. Fig. 9 When three user STAs are allocated to 106-RU based on the MU-MIMO scheme, N_user is set to "3". Therefore, the values ​​of N_STS[1], N_STS[2], and N_STS[3] can be determined as shown in Table 3. For example, when the value of the second bit (B11-B14) is "0011", it can be set to N_STS[1]=4, N_STS[2]=1, and N_STS[3]=1. That is, in Fig. 9 In the example of , four spatial streams may be allocated to user field 1, one spatial stream may be allocated to user field 1, and one spatial stream may be allocated to user field 3.

[0137] As shown in the examples of Table 3 and / or Table 4, the information about the number of spatial streams for the user STA (i.e., the second bits, B11-B14) may consist of 4 bits. In addition, the information about the number of spatial streams for the user STA (i.e., the second bits, B11-B14) may support up to eight spatial streams. In addition, the information about the number of spatial streams for the user STA (i.e., the second bits, B11-B14) may support up to four spatial streams for one user STA.

[0138] In addition, the third bit (ie, B15-18) in the user field (ie, 21 bits) may include modulation and coding scheme (MCS) information. The MCS information may be applied to the data field in the PPDU including the corresponding SIG-B.

[0139] MCS, MCS information, MCS index, MCS field, etc. used in this specification may be indicated by an index value. For example, MCS information may be indicated by index 0 to index 11. MCS information may include information related to constellation modulation type (e.g., BPSK, QPSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM, etc.) and information related to coding rate (e.g., 1 / 2, 2 / 3, 3 / 4, 5 / 6e, etc.). Information related to channel coding type (e.g., LCC or LDPC) may not be included in the MCS information.

[0140] In addition, the fourth bit (ie, B19) in the user field (ie, 21 bits) may be a reserved field.

[0141] In addition, the fifth bit (ie, B20) in the user field (ie, 21 bits) may include information on a coding type (eg, BCC or LDPC). That is, the fifth bit (ie, B20) may include information on a type of channel coding (eg, BCC or LDPC) applied to a data field in a PPDU including a corresponding SIG-B.

[0142] The above example relates to a user field in the first format (format of the MU-MIMO scheme). An example of a user field in the second format (format of a non-MU-MIMO scheme) is as follows.

[0143] The first bit (e.g., B0-B10) in the user field of the second format may include identification information of the user STA. In addition, the second bit (e.g., B11-B13) in the user field of the second format may include information related to the number of spatial streams applied to the corresponding RU. In addition, the third bit (e.g., B14) in the user field of the second format may include information related to whether a beamforming steering matrix is ​​applied. The fourth bit (e.g., B15-B18) in the user field of the second format may include modulation and coding scheme (MCS) information. In addition, the fifth bit (e.g., B19) in the user field of the second format may include information related to whether dual carrier modulation (DCM) is applied. In addition, the sixth bit (i.e., B20) in the user field of the second format may include information related to the coding type (e.g., BCC or LDPC).

[0144] Fig.10UL-MU-based operation is shown. As shown, a transmitting STA (e.g., an AP) may perform channel access through contention (e.g., a backoff operation), and may transmit a trigger frame 1030. That is, the transmitting STA may transmit a PPDU including the trigger frame 1030. Upon receiving the PPDU including the trigger frame, a trigger-based (TB) PPDU is transmitted after a delay corresponding to SIFS.

[0145] The TB PPDUs 1041 and 1042 may be transmitted at the same time period, and may be transmitted from a plurality of STAs (eg, user STAs) having the AID indicated in the trigger frame 1030. The ACK frame 1050 for the TB PPDU may be implemented in various forms.

[0146] Reference Figures 11 to 13 Describes specific features of the trigger frame. Even when UL-MU communication is used, an Orthogonal Frequency Division Multiple Access (OFDMA) scheme or a MU-MIMO scheme may be used, and OFDMA and MU-MIMO schemes may be used simultaneously.

[0147] Fig.11 An example of a trigger frame is shown. Fig.11 The trigger frame allocates resources for uplink multi-user (MU) transmission and may be sent, for example, from an AP. The trigger frame may be configured by a MAC frame and may be included in a PPDU.

[0148] Fig.11 The various fields shown may be partially omitted, and another field may be added. In addition, the length of each field may be changed to be different from that shown in the figure.

[0149] Fig.11 The frame control field 1110 may include information related to the MAC protocol version and additional additional control information. The duration field 1120 may include time information configured by the NAV or information related to an identifier (eg, AID) of the STA.

[0150] In addition, the RA field 1130 may include address information of the receiving STA of the corresponding trigger frame, and may be optionally omitted. The TA field 1140 may include address information of the STA (e.g., AP) that sends the corresponding trigger frame. The public information field 1150 includes public control information applied to the receiving STA that receives the corresponding trigger frame. For example, it may include a field indicating the length of the L-SIG field of the uplink PPDU sent in response to the corresponding trigger frame or information for controlling the content of the SIG-A field (i.e., HE-SIG-A field) of the uplink PPDU sent in response to the corresponding trigger frame. In addition, as public control information, information related to the length of the CP of the uplink PPDU sent in response to the corresponding trigger frame or information related to the length of the LTF field may be included.

[0151] In addition, preferably including and receiving Fig.11 The number of receiving STAs of the trigger frame corresponds to the per-user information fields 1160#1 to 1160#N. The per-user information field may also be referred to as an "allocation field".

[0152] in addition, Fig.11 The trigger frame may include a padding field 1170 and a frame check sequence field 1180.

[0153] Fig.11 Each of the illustrated per-user information fields 1160#1 to 1160#N may include a plurality of subfields.

[0154] Fig.12 An example of a common information field of a trigger frame is shown. Fig.12 The subfields of may be partially omitted, and additional subfields may be added. In addition, the length of each subfield shown may be changed.

[0155] The length field 1210 shown has the same value as the length field of the L-SIG field of the uplink PPDU sent in response to the corresponding trigger frame, and the length field of the L-SIG field of the uplink PPDU indicates the length of the uplink PPDU. As a result, the length field 1210 of the trigger frame can be used to indicate the length of the corresponding uplink PPDU.

[0156] In addition, the tandem identifier field 1220 indicates whether a tandem operation is performed. The tandem operation means that downlink MU transmission and uplink MU transmission are performed together in the same TXOP. That is, it means that downlink MU transmission is performed, and then uplink MU transmission is performed after a preset time (e.g., SIFS). During the tandem operation, only one transmitting device (e.g., AP) can perform downlink communication, and multiple transmitting devices (e.g., non-AP) can perform uplink communication.

[0157] The CS request field 1230 indicates whether a wireless medium status or NAV, etc. must be considered in a case where a receiving device that has received a corresponding trigger frame transmits a corresponding uplink PPDU.

[0158] The HE-SIG-A information field 1240 may include information for controlling the content of the SIG-A field (ie, HE-SIG-A field) of the uplink PPDU in response to the corresponding trigger frame.

[0159] The CP and LTF type field 1250 may include information about the CP length and LTF length of the uplink PPDU sent in response to the corresponding trigger frame. The trigger type field 1260 may indicate the purpose of using the corresponding trigger frame, such as a typical trigger, a beamforming trigger, requesting a block ACK / NACK, etc.

[0160] It may be assumed that the trigger type field 1260 of the trigger frame in this specification indicates a basic type of trigger frame for a typical trigger. For example, the basic type of trigger frame may be referred to as a basic trigger frame.

[0161] Fig.13 An example of subfields included in the per-user information field is shown. Fig.13 The user information field 1300 may be understood as referring to the above Fig.11 Any of the per-user information fields 1160#1 to 1160#N mentioned above. Included in Fig.13 The subfields in the user information field 1300 may be partially omitted, and additional subfields may be added. In addition, the length of each subfield shown may be changed.

[0162] Fig.13 The user identifier field 1310 indicates an identifier of the STA (ie, the receiving STA) corresponding to the per-user information. An example of the identifier may be all or part of an association identifier (AID) value of the receiving STA.

[0163] In addition, the RU allocation field 1320 may be included. That is, when the receiving STA identified by the user identifier field 1310 transmits a TB PPDU in response to the trigger frame, the TB PPDU is transmitted through the RU indicated by the RU allocation field 1320. In this case, the RU indicated by the RU allocation field 1320 may be Figure 5 , Figure 6 and Figure 7 RU shown.

[0164] Fig.13 The subfield of may include a coding type field 1330. The coding type field 1330 may indicate the coding type of the TB PPDU. For example, when BCC coding is applied to the TB PPDU, the coding type field 1330 may be set to "1", and when LDPC coding is applied, the coding type field 1330 may be set to "0".

[0165] in addition, Fig.13The subfield of may include an MCS field 1340. The MCS field 1340 may indicate the MCS scheme applied to the TB PPDU. For example, when BCC encoding is applied to the TB PPDU, the coding type field 1330 may be set to "1", and when LDPC encoding is applied, the coding type field 1330 may be set to "0".

[0166] Hereinafter, a UL OFDMA-based random access (UORA) scheme will be described.

[0167] Fig.14 Describe the technical features of the UORA scheme.

[0168] The sending STA (e.g., AP) can Fig.14 Specifically, the AP may allocate the first RU resource (AID 0, RU 1), the second RU resource (AID 0, RU 2), the third RU resource (AID 0, RU 3), the fourth RU resource (AID 2045, RU 4), ​​the fifth RU resource (AID 2045, RU 5), and the sixth RU resource (AID 3, RU 6). Information related to AID 0, AID 3, or AID 2045 may be included in, for example, Fig.13 The information related to RU 1 to RU 6 may be included in, for example, the user identifier field 1310. Fig.13 AID=0 may mean UORA resources for associated STAs, and AID=2045 may mean UORA resources for non-associated STAs. Fig.14 The 1st to 3rd RU resources can be used as UORA resources for associated STAs. Fig.14 The 4th RU resource and the 5th RU resource can be used as UORA resources for non-associated STAs. Fig.14 The 6th RU resources may be used as typical resources for UL MU.

[0169] exist Fig.14 In the example, STA1's OFDMA random access backoff (OBO) is reduced to 0, and STA1 randomly selects the second RU resource (AID 0, RU 2). In addition, since STA2 / 3's OBO counter is greater than 0, no uplink resources are allocated to STA2 / 3. Fig.14 For STA4 in , since the AID of STA4 (eg, AID=3) is included in the trigger frame, resources of RU 6 are allocated without backoff.

[0170] Specifically, due to Fig.14STA1 is the associated STA, so the total number of qualified RARUs for STA1 is 3 (RU1, RU 2, and RU 3), so STA1 decrements the OBO counter by 3 to make the OBO counter 0. In addition, since Fig.14 STA2 is the associated STA, so the total number of eligible RA RUs for STA2 is 3 (RU 1, RU 2, and RU 3), so STA2 decrements the OBO counter by 3, but the OBO counter is greater than 0. In addition, due to Fig.14 STA3 is a non-associated STA, so the total number of eligible RA RUs for STA3 is 2 (RU 4, RU 5), so STA3 decrements the OBO counter by 2, but the OBO counter is greater than 0.

[0171] Fig.15 An example of channels used / supported / defined in the 2.4 GHz band is shown.

[0172] The 2.4 GHz band may be referred to as other terms such as a first frequency band. In addition, the 2.4 GHz band may mean a frequency domain that uses / supports / defines channels having center frequencies close to 2.4 GHz (eg, channels having center frequencies within 2.4 to 2.5 GHz).

[0173] A plurality of 20 MHz channels may be included in the 2.4 GHz frequency band. The 20 MHz in 2.4 GHz may have a plurality of channel indices (e.g., index 1 to index 14). For example, the center frequency of a 20 MHz channel assigned with channel index 1 may be 2.412 GHz, the center frequency of a 20 MHz channel assigned with channel index 2 may be 2.417 GHz, and the center frequency of a 20 MHz channel assigned with channel index N may be (2.407+0.005*N) GHz. The channel index may be referred to as various terms such as channel number, etc. The specific values ​​of the channel index and the center frequency may vary.

[0174] Fig.15 An example is given of 4 channels in the 2.4 GHz frequency band. Each of the 1st frequency domain 1510 to the 4th frequency domain 1540 shown herein may include one channel. For example, the 1st frequency domain 1510 may include channel 1 (a 20 MHz channel with index 1). In this case, the center frequency of channel 1 may be set to 2412 MHz. The 2nd frequency domain 1520 may include channel 6. In this case, the center frequency of channel 6 may be set to 2437 MHz. The 3rd frequency domain 1530 may include channel 11. In this case, the center frequency of channel 11 may be set to 2462 MHz. The 4th frequency domain 1540 may include channel 14. In this case, the center frequency of channel 14 may be set to 2484 MHz.

[0175] Fig.16 Shows an example of channels used / supported / defined in the 5 GHz band.

[0176] The 5 GHz band may be referred to as other terms such as a second frequency band, etc. The 5 GHz band may mean a frequency domain that uses / supports / defines channels with a center frequency greater than or equal to 5 GHz and less than 6 GHz (or less than 5.9 GHz). Alternatively, the 5 GHz band may include multiple channels between 4.5 GHz and 5.5 GHz. Fig.16 The specific values ​​shown may vary.

[0177] Multiple channels within the 5 GHz band include Unlicensed National Information Infrastructure (UNII)-1, UNII-2, UNII-3, and ISM. UNII-1 may be referred to as UNII Low. UNII-2 may include frequency domains referred to as UNII Mid and UNII-2 Extended. UNII-3 may be referred to as UNII-Upper.

[0178] A plurality of channels may be configured within the 5 GHz frequency band, and the bandwidth of each channel may be set differently, for example, to 20 MHz, 40 MHz, 80 MHz, 160 MHz, etc. For example, the 5170 MHz to 5330 MHz frequency domain / range within UNII-1 and UNII-2 may be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency domain / range may be divided into four channels via a 40 MHz frequency domain. The 5170 MHz to 5330 MHz frequency domain / range may be divided into two channels via an 80 MHz frequency domain. Alternatively, the 5170 MHz to 5330 MHz frequency domain / range may be divided into one channel via a 160 MHz frequency domain.

[0179] Fig.17 Shows examples of channels used / supported / defined in the 6 GHz band.

[0180] The 6 GHz frequency band may be referred to as other terms such as a third frequency band, etc. The 6 GHz frequency band may mean a frequency domain that uses / supports / defines channels having center frequencies greater than or equal to 5.9 GHz. Fig.17 The specific values ​​shown may vary.

[0181] For example, Fig.17 The 20MHz channel can be defined starting from 5.940GHz. Fig.17 Among the 20 MHz channels of the channel, the leftmost channel may have an index of 1 (or a channel index, a channel number, etc.), and 5.945 GHz may be assigned as the center frequency. That is, the center frequency of the channel of index N may be determined to be (5.940+0.005*N) GHz.

[0182] therefore, Fig.17 The index (or channel number) of the 2MHz channel can be 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, 201, 205, 209, 213, 217, 221, 225, 229, 233. In addition, according to the above (5.940+0.005*N)GHz rule, Fig.17 The index of the 40MHz channels can 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.

[0183] Despite Fig.17 20, 40, 80, and 160 MHz channels are shown in the example of , but a 240 MHz channel or a 320 MHz channel may be additionally added.

[0184] Hereinafter, a PPDU transmitted / received in a STA of the present specification will be described.

[0185] Fig.18 An example of PPDU used in this specification is shown.

[0186] Fig.18 The PPDU of the EHT PPDU may be referred to as various terms such as EHT PPDU, TX PPDU, RX PPDU, first type or Nth type PPDU, etc. For example, in the present specification, PPDU or EHT PPDU may be referred to as various terms such as TX PPDU, RX PPDU, first type or Nth type PPDU, etc. In addition, the EHT PPDU may be used in the EHT system and / or a new WLAN system enhanced from the EHT system.

[0187] Fig.18 The PPDU may indicate all or part of the PPDU type used in the EHT system. For example, Fig.18 The example of can be used for both single user (SU) mode and multi-user (MU) mode. In other words, Fig.18 The PPDU may be a PPDU for one receiving STA or multiple receiving STAs. Fig.18 When the PPDU is used in trigger-based (TB) mode, it can be omitted Fig.18 In other words, a STA that has received a trigger frame for uplink MU (UL-MU) may send Fig.18 The PPDU of EHT-SIG is omitted in the example.

[0188] exist Fig.18 In the present invention, L-STF to EHT-LTF may be referred to as a preamble or a physical preamble and may be generated / sent / received / obtained / decoded in a physical layer.

[0189] Fig.18 The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG and EHT-SIG fields can be determined to be 312.5kHz, and the subcarrier spacing of the EHT-STF, EHT-LTF and data fields can be determined to be 78.125kHz. That is, the tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG and EHT-SIG fields can be expressed in units of 312.5kHz, and the tone index (or subcarrier index) of the EHT-STF, EHT-LTF and data fields can be expressed in units of 78.125kHz.

[0190] exist Fig.18 In the PPDU, L-LTE and L-STF can be the same as those in the legacy fields.

[0191] For example, Fig.18 The L-SIG field may include 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 include information related to the length or duration of the PPDU. For example, the 12-bit length field may be determined based on the type of the PPDU. For example, when the PPDU is a non-HT, HT, VHT PPDU, or EHT PPDU, the value of the length field may be determined as a multiple of 3. For example, when 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 PPDI, or EHT PPDU, the value of the length field may be determined as "a multiple of 3", and for HE PPDU, the value of the length field may be determined as "a multiple of 3" + 1 or "a multiple of 3" + 2.

[0192] For example, the transmitting STA may apply BCC encoding based on a 1 / 2 coding rate to the 24-bit information of the L-SIG field. Thereafter, the transmitting STA may obtain 48 bits of BCC coded bits. BPSK modulation may be applied to the 48-bit coded bits, thereby generating 48 BPSK symbols. The transmitting STA may map the 48 BPSK symbols to positions other than the pilot subcarriers {subcarrier indexes -21, -7, +7, +21} and the DC subcarrier {subcarrier index 0}. As a result, the 48 BPSK symbols may be mapped to subcarrier indexes -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. The transmitting STA may additionally map the signal of {-1, -1, -1, 1} to the subcarrier index {-28, -27, +27, +28}. The above signal may be used for channel estimation in the frequency domain corresponding to {-28, -27, +27, +28}.

[0193] The transmitting STA may generate the RL-SIG in the same manner as the L-SIG. BPSK modulation may be applied to the RL-SIG. The receiving STA may know whether the RX PPDU is a HE PPDU or an EHT PPDU based on the presence of the RL-SIG.

[0194] Universal SIG (U-SIG) can be inserted in Fig.18 The U-SIB may be referred to by various terms such as a first SIG field, a first SIG, a first type SIG, a control signal, a control signal field, a first (type) control signal, etc.

[0195] The U-SIG may include N bits of information and may include information for identifying the type of the EHT PPDU. For example, the U-SIG may be configured based on two symbols (e.g., two adjacent OFDM symbols). Each symbol of the U-SIG (e.g., OFDM symbol) may have a duration of 4 μs. Each symbol of the U-SIG may be used to send 26 bits of information. For example, each symbol of the U-SIG may be sent / received based on 52 data tones and 4 pilot tones.

[0196] For example, through U-SIG (or U-SIG field), A-bit information (e.g., 52 uncoded bits) may be transmitted. The first symbol of U-SIG may transmit the first X bits of information of A-bit information (e.g., 26 uncoded bits), and the second symbol of U-SIB may transmit the remaining Y bits of information of A-bit information (e.g., 26 uncoded bits). For example, the transmitting STA may obtain 26 uncoded bits included in each U-SIG symbol. The transmitting STA may perform convolutional coding (i.e., BCC coding) based on a rate of R=1 / 2 to generate 52 coded bits, and may perform interleaving on the 52 coded bits. The transmitting STA may perform BPSK modulation on the interleaved 52 coded bits to generate 52 BPSK symbols to be allocated to each U-SIG symbol. In addition to DC index 0, one U-SIG symbol may be transmitted based on 65 tones (subcarriers) from subcarrier index -28 to subcarrier index +28. The 52 BPSK symbols generated by the transmitting STA may be transmitted based on the remaining tones (subcarriers) except the pilot tones (ie, tones -21, -7, +7, +21).

[0197] For example, the A-bit information (e.g., 52 uncoded bits) generated by the U-SIG may include a CRC field (e.g., a field having a length of 4 bits) and a tail field (e.g., a field having a length of 6 bits). The CRC field and the tail field may be transmitted through the second symbol of the U-SIG. The CRC field may be generated based on the 26 bits of the first symbol allocated to the U-SIG and the remaining 16 bits of the second symbol excluding the CRC / tail field, and may be generated based on a conventional CRC calculation algorithm. In addition, the tail field may be used to terminate the grid of the convolutional decoder and may be set to, for example, "000000".

[0198] A bit information (e.g., 52 uncoded bits) transmitted by U-SIG (or U-SIG field) may be divided into version-independent bits and version-dependent bits. For example, the version-independent bits may have a fixed size or a variable size. For example, the version-independent bits may be allocated only to the first symbol of the U-SIG, or the version-independent bits may be allocated to both the first symbol and the second symbol of the U-SIG. For example, the version-independent bits and the version-dependent bits may be referred to as various terms such as first control bits, second control bits, etc.

[0199] For example, the version-independent bits of the 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 TX / RX PPDU. For example, the first value of the 3-bit PHY version identifier may indicate that the TX / RX PPDU is an EHT PPDU. In other words, when the transmitting STA transmits an EHT PPDU, the 3-bit PHY version identifier may be set to a first value. In other words, based on the PHY version identifier having a first value, the receiving STA may determine that the RX PPDU is an EHT PPDU.

[0200] For example, the version-independent bit U-SIG may include a 1-bit UL / DL flag field. A first value of the 1-bit UL / DL flag field relates to UL communication, and a second value of the UL / DL flag field relates to DL communication.

[0201] For example, the version-independent bits of the U-SIG may include information related to the TXOP length and information related to the BSS color ID.

[0202] For example, when the EHT PPDU is divided into various types (for example, various types such as EHT PPDU related to SU mode, EHT PPDU related to MU mode, EHT PPDU related to TB mode, EHT PPDU related to extended range transmission, etc.), information related to the type of the EHT PPDU may be included in the version-related bit of the U-SIG.

[0203] For example, the U-SIG may include: 1) a bandwidth field including information related to the bandwidth; 2) a field including information related to the MCS scheme applied to the EHT-SIG; 3) an indication field including information on whether a dual subcarrier modulation (DCM) scheme is applied to the EHT-SIG; 4) a field including information on the number of symbols used for the EHT-SIG; 5) a field including information on whether the EHT-SIG is generated across the full frequency band; 6) a field including information on the type of EHT-LTF / STF; and 7) information related to a field indicating the EHT-LTF length and the CP length.

[0204] Can Fig.18 Preamble puncturing is applied to the PPDU of the primary 20 MHz band. Preamble puncturing means applying puncturing to part of the full band (e.g., the secondary 20 MHz band). For example, when sending an 80 MHz PPDU, the STA may apply puncturing to the secondary 20 MHz band in the 80 MHz band, and may send the PPDU only through the primary 20 MHz band and the secondary 40 MHz band.

[0205] For example, the pattern of preamble puncturing may be preconfigured. For example, when the first puncturing pattern is applied, puncturing may be applied only to the auxiliary 20 MHz band within the 80 MHz band. For example, when the second puncturing pattern is applied, puncturing may be applied only to any one of the two auxiliary 20 MHz bands included in the auxiliary 40 MHz band within the 80 MHz band. For example, when the third puncturing pattern is applied, puncturing may be applied only to the auxiliary 20 MHz band included in the main 80 MHz band within the 160 MHz band (or the 80+80 MHz band). For example, when the fourth puncturing is applied, puncturing may be applied to at least one 20 MHz channel that does not belong to the main 40 MHz band in the presence of the main 40 MHz band included in the 80 MHaz band within the 160 MHz band (or the 80+80 MHz band).

[0206] Information related to the preamble puncturing applied to the PPDU may be included in the U-SIG and / or the EHT-SIG. For example, the first field of the U-SIG may include information related to the contiguous bandwidth, and the second field of the U-SIG may include information related to the preamble puncturing applied to the PPDU.

[0207] For example, based on the following method, the U-SIG and the EHT-SIG may include information related to preamble puncturing. When the bandwidth of the PPDU exceeds 80 MHz, the U-SIG may be configured separately in units of 80 MHz. For example, when the bandwidth of the PPDU is 160 MHz, the PPDU may include a first U-SIG for a first 80 MHz band and a second U-SIG for a second 80 MHz band. In this case, the first field of the first U-SIG may include information related to the 160 MHz bandwidth, and the second field of the first U-SIG may include information related to the preamble puncturing applied to the first 80 MHz band (i.e., information related to the preamble puncturing pattern). In addition, the first field of the second U-SIG may include information related to the 160 MHz bandwidth, and the second field of the second U-SIG may include information related to the preamble puncturing applied to the second 80 MHz band (i.e., information related to the preamble puncturing pattern). In addition, the EHT-SIG adjacent to the first U-SIG may include information related to the preamble puncturing applied to the second 80 MHz frequency band (i.e., information related to the preamble puncturing pattern), and the EHT-SIG adjacent to the second U-SIG may include information related to the preamble puncturing applied to the first 80 MHz frequency band (i.e., information related to the preamble puncturing pattern).

[0208] Additionally or alternatively, based on the following method, the U-SIG and the EHT-SIG may include information related to preamble puncturing. The U-SIG may include information related to preamble puncturing for all frequency bands (i.e., information related to the preamble puncturing pattern). That is, the EHT-SIG may not include information related to preamble puncturing, and only the U-SIG may include information related to preamble puncturing (i.e., information related to the preamble puncturing pattern).

[0209] The U-SIG may be configured in units of 20 MHz. For example, when configuring an 80 MHz PPDU, the U-SIG may be duplicated. That is, four identical U-SIGs may be included in the 80 MHz PPDU. A PPDU with a bandwidth exceeding 80 MHz may include different U-SIGs.

[0210] Fig.18 The EHT-SIG may include control information for receiving STAs. The EHT-SIG may be transmitted through at least one symbol, and one symbol may have a length of 4us. Information on the number of symbols used for the EHT-SIG may be included in the U-SIG.

[0211] The EHT-SIG may include reference Figure 8 and Fig. 9 The technical features of HE-SIG-B are described in detail. Figure 8 As in the example of , the EHT-SIG may include a common field and a user-specific field. The common field of the EHT-SIG may be omitted, and the number of user-specific fields may be determined based on the number of users.

[0212] like Figure 8 As in the example of , the common field of EHT-SIG and the user-specific field of EHT-SIG may be encoded separately. One user block field included in the user-specific field may include information for two users, but the optimal one user block field included in the user-specific field may include information for one user. That is, one user block field of EHT-SIG may include at most two user fields. Fig. 9 As in the example of , each user field may be associated with a MU-MIMO allocation or may be associated with a non-MU-MIMO allocation.

[0213] like Figure 8 As in the example of , the common field of EHT-SIG may include CRC bits and tail bits. The length of the CRC bits may be determined to be 4 bits. The length of the tail bits may be determined to be 6 bits and may be set to "000000".

[0214] like Figure 8As in the example of , the common field of EHT-SIG may include RU allocation information. The RU allocation information may imply information related to the location of the RU to which multiple users (ie, multiple receiving STAs) are allocated. As in Table 1, the RU allocation information may be configured in units of 8 bits (or N bits).

[0215] The examples of Tables 5 to 7 are examples of 8-bit (or N-bit) information for various RU allocations. The indexes shown in the respective tables may be modified, and some entries in Tables 5 to 7 may be omitted, and entries may be added (not shown).

[0216] The examples of Tables 5 to 7 relate to information related to the location of RUs allocated to the 20 MHz frequency band. For example, "index 0" of Table 5 may be in the case where nine 26-RUs are allocated separately (e.g., Figure 5 Nine 26-RU cases are shown) for use.

[0217] In addition, multiple RUs may be allocated to one STA in the EHT system. For example, with respect to "index 60" of Table 6, one 26-RU may be allocated to the leftmost side of the 20 MHz band for one user (ie, receiving STA), one 26-RU and one 52-RU may be allocated to the right side thereof, and five 26-RUs may be allocated to the right side thereof alone.

[0218] [Table 5]

[0219]

[0220] [Table 6]

[0221]

[0222] [Table 7]

[0223]

[0224] A mode in which the common fields of the EHT-SIG are omitted may be supported. The mode in which the common fields of the EHT-SIG are omitted may be referred to as a compressed mode. When the compressed mode is used, multiple users (i.e., multiple receiving STAs) may decode the PPDU (e.g., the data field of the PPDU) based on non-OFDMA. That is, multiple users of the EHT PPDU may decode the PPDU (e.g., the data field of the PPDU) received via the same frequency band. In addition, when the non-compressed mode is used, multiple users of the EHT PPDU may decode the PPDU (e.g., the data field of the PPDU) based on OFDMA. That is, multiple users of the EHT PPDU may receive the PPDU (e.g., the data field of the PPDU) via different frequency bands.

[0225] The EHT-SIG may be configured based on various MCS schemes. As described above, information about the MCS scheme applied to the EHT-SIG may be included in the U-SIG. The EHT-SIG may be configured based on the DCM scheme. For example, among the N data tones (e.g., 52 data tones) allocated to the EHT-SIG, a first modulation scheme may be applied to half of the adjacent tones, and a second modulation scheme may be applied to the remaining half of the adjacent tones. That is, the transmitting STA may use a first modulation scheme to modulate specific control information using a first symbol and assign it to half of the adjacent tones, and may use a second modulation scheme to modulate the same control information using a second symbol and assign it to the remaining half of the adjacent tones. As described above, information (e.g., a 1-bit field) about whether the DCM scheme is applied to the EHT-SIG may be included in the U-SIG.

[0226] Fig.18 The HE-STF can be used to improve automatic gain control estimation in a multiple-input multiple-output (MIMO) environment or an OFDMA environment. Fig.18 The HE-LTF can be used to estimate channels in a MIMO environment or an OFDMA environment.

[0227] Fig.18 The EHT-STF can be set to various types. For example, a first type of STF (e.g., 1x STF) may be generated based on a first type of STF sequence in which non-zero coefficients are arranged at intervals of 16 subcarriers. The STF signal generated based on the first type of STF sequence may have a period of 0.8 μs, and the periodic signal of 0.8 μs may be repeated 5 times to become a first type of STF having a length of 4 μs. For example, a second type of STF (e.g., 2x STF) may be generated based on a second type of STF sequence in which non-zero coefficients are arranged at intervals of 8 subcarriers. The STF signal generated based on the second type of STF sequence may have a period of 1.6 μs, and the periodic signal of 1.6 μs may be repeated 5 times to become a second type of STF having a length of 8 μs. In the following, an example of a sequence for configuring the EHT-STF (i.e., an EHT-STF sequence) is proposed. The following sequence may be modified in various ways.

[0228] The EHT-STF may be configured based on the following sequence M.

[0229] <Formula 1>

[0230] M={-1,-1,-1,1,1,1,-1,1,1,1,-1,1,1,-1,1}

[0231] The EHT-STF for a 20MHz PPDU may be configured based on the following formula. The following example may be a first type (i.e., 1xSTF) sequence. For example, the first type sequence may not be included in a trigger-based (TB) PPDU, but may be included in an EHT-PPDU. In the following formula, (a:b:c) may mean the duration of a b-tone interval (i.e., subcarrier interval) defined as from a tone index (i.e., subcarrier index) "a" to a tone index "c". For example, the following formula 2 may represent a sequence of 16 tone intervals defined as from a tone index -112 to a tone index 112. Since a subcarrier spacing of 78.125kHz is applied to the EHT-STR, the 16-tone interval may mean that the EHT-STF coefficients (or elements) are arranged at intervals of 78.125*16=1250kHz. In addition, * means multiplication, and sqrt() means square root. In addition, j means an imaginary number.

[0232] <Formula 2>

[0233] EHT-STF(-112:16:112)={M}*(1+j) / sqrt(2)

[0234] EHT-STF(0)=0

[0235] The EHT-STF for a 40 MHz PPDU may be configured based on the following formula: The following example may be a first type (ie, 1xSTF) sequence.

[0236] <Formula 3>

[0237] EHT-STF(-240:16:240)={M,0,-M}*(1+j) / sqrt(2)

[0238] The EHT-STF for 80MHz PPDU may be configured based on the following formula: The following example may be a first type (ie, 1xSTF) sequence.

[0239] <Formula 4>

[0240] EHT-STF(-496:16:496)={M,1,-M,0,-M,1,-M}*(1+j) / sqrt(2)

[0241] The EHT-STF for 160MHz PPDU may be configured based on the following formula: The following example may be a first type (ie, 1xSTF) sequence.

[0242] <Formula 5>

[0243] EHT-STF(-1008:16:1008)={M,1,-M,0,-M,1,-M,0,-M,-1,M,0,-M,1,-M}*(1+j) / sqrt(2)

[0244] In the EHT-STF for 80+80 MHz PPDU, the sequence for the lower 80 MHz may be the same as Equation 4. In the EHT-STF for 80+80 MHz PPDU, the sequence for the upper 80 MHz may be configured based on the following equation.

[0245] <Formula 6>

[0246] EHT-STF(-496:16:496)={-M,-1,M,0,-M,1,-M}*(1+j) / sqrt(2)

[0247] The following Equations 7 to 11 relate to examples of the second type (ie, 2x STF) sequence.

[0248] <Formula 7>

[0249] EHT-STF(-120:8:120)={M,0,-M}*(1+j) / sqrt(2)

[0250] The EHT-STF for 40 MHz PPDU may be configured based on the following formula.

[0251] <Formula 8>

[0252] EHT-STF(-248:8:248)={M,-1,-M,0,M,-1,M}*(1+j) / sqrt(2)

[0253] EHT-STF(-248)=0

[0254] EHT-STF(248)=0

[0255] The EHT-STF for 80 MHz PPDU may be configured based on the following formula.

[0256] <Formula 9>

[0257] EHT-STF(-504:8:504)={M,-1,M,-1,-M,-1,M,0,-M,1,M,1,-M,1,-M}*(1+j) / sqrt(2)

[0258] The EHT-STF for 160 MHz PPDU may be configured based on the following formula.

[0259] <Formula 10>

[0260] EHT-STF(-1016:16:1016)={M,-1,M,-1,-M,-1,M,0,-M,1,M,1,-M,1,-M,0,-M,1,-M,1,M,1,-M,0,-M,1,M,1,-M,1,-M}*(1+j) / sqrt(2)

[0261] EHT-STF(-8)=0,EHT-STF(8)=0,

[0262] EHT-STF(-1016)=0,EHT-STF(1016)=0

[0263] In the EHT-STF for 80+80 MHz PPDU, the sequence for the lower 80 MHz may be the same as Equation 9. In the EHT-STF for 80+80 MHz PPDU, the sequence for the upper 80 MHz may be configured based on the following equation.

[0264] <Formula 11>

[0265] EHT-STF(-504:8:504)={-M,1,-M,1,M,1,-M,0,-M,1,M,1,-M,1,-M}*(1+j) / sqrt(2)

[0266] EHT-STF(-504)=0,

[0267] EHT-STF(504)=0

[0268] The EHT-LTF may have a first type, a second type, and a third type (ie, 1x, 2x, 4x LTF). For example, the first / second / third type LTF may be generated based on an LTF sequence in which non-zero coefficients are arranged at intervals of 4 / 2 / 1 subcarriers. The first / second / third type LTF may have a time length of 3.2 / 6.4 / 12.8 μs. In addition, GIs of various lengths (eg, 0.8 / 1 / 6 / 3.2 μs) may be applied to the first / second / third type LTF.

[0269] Information about the type of STF and / or LTF (including information about the GI applied to the LTF) may be included in Fig.18 SIG-A field and / or SIG-B field, etc.

[0270] Fig.18 The PPDU (e.g., EHT-PPDU) may be based on Figure 5 and Figure 6 to configure the example.

[0271] For example, an EHT PPDU transmitted on a 20 MHz frequency band (ie, a 20 MHz EHT PPDU) may be based on Figure 5 That is, the location of the RUs of the EHT-STF, EHT-LTF, and data fields included in the EHT PPDU may be as follows: Figure 5 OK as shown.

[0272] The EHT PPDU transmitted in the 40 MHz band (ie, 40 MHz EHT PPDU) may be based on Figure 6 That is, the location of the RUs of the EHT-STF, EHT-LTF, and data fields included in the EHT PPDU may be as follows: Figure 6 OK as shown.

[0273] because Figure 6 The RU position corresponds to 40MHz, so when Figure 6 The tone plan for 80 MHz can be determined when the pattern is repeated twice. Figure 7 The RU is Figure 6 The RU repeats the new tone schedule twice to send the 80MHz EHT PPDU.

[0274] when Figure 6 When the pattern of is repeated twice, 23 tones (i.e., 11 guard tones + 12 guard tones) may be configured in the DC region. That is, the tone plan of the 80MHz EHT PPDU allocated based on OFDMA may have 23 DC tones. Different from this, the 80MHz EHT PPDU allocated based on non-OFDMA (i.e., non-OFDMA full bandwidth 80MHz PPDU) may be configured based on 996-RU and may include 5 DC tones, 12 left guard tones, and 11 right guard tones.

[0275] The tone plan for 160 / 240 / 320MHz can be Figure 6 The pattern is configured in a manner that is repeated multiple times.

[0276] Fig.18 The PPDU may be determined (or identified) as an EHT PPDU based on the following method.

[0277] The receiving STA may determine the type of the RX PPDU as an EHT PPDU based on the following aspects. For example, 1) when the first symbol after the L-LTF signal of the RX PPDU is a BPSK symbol; 2) when the RL-SIG in which the L-SIG of the RX PPDU is repeated is detected; and 3) when the result of applying "modulo 3" to the value of the length field of the L-SIG of the RX PPDU is detected as "0", the RX PPDU may be determined as an EHT PPDU. When the RX PPDU is determined to be an EHT PPDU, the receiving STA may determine the type of the RX PPDU as an EHT PPDU based on Fig.18 The type of the EHT PPDU (e.g., SU / MU / triggered / extended range type) is detected by bit information included in the symbol after the RL-SIG of the U-SIG. In other words, based on: 1) the first symbol after the L-LTF signal which is a BPSK symbol; 2) the RL-SIG which is adjacent to the L-SIG field and is the same as the L-SIG; 3) the L-SIG including the length field to which the result of applying "modulo 3" is set to "0"; and 4) the 3-bit PHY version identifier of the above-mentioned U-SIG (e.g., the PHY version identifier having the first value), the receiving STA can determine that the RX PPDU is an EHT PPDU.

[0278] For example, the receiving STA may determine the type of the RX PPDU as the EHT PPDU based on the following aspects. For example, 1) when the first symbol after the L-LTF signal is a BPSK symbol; 2) when the RL-SIG in which the L-SIG is repeated is detected; and 3) when the result of applying "modulo 3" to the value of the length field of the L-SIG is detected as "1" or "2", the RX PPDU may be determined as the HEPPDU.

[0279] For example, the receiving STA may determine the type of the RX PPDU as non-HT, HT, and VHT PPDU based on the following aspects. For example, 1) when the first symbol after the L-LTF signal is a BPSK symbol; and 2) when the RL-SIG in which the L-SIG is repeated is not detected, the RX PPDU may be determined as non-HT, HT, and VHT PPDU. In addition, even if the receiving STA detects RL-SIG repetition, when the result of applying "modulo 3" to the length value of the L-SIG is detected as "0", the RX PPDU may be determined as non-HT, HT, and VHT PPDU.

[0280] In the following examples, signals represented as (TX / RX / UL / DL) signals, (TX / RX / UL / DL) frames, (TX / RX / UL / DL) packets, (TX / RX / UL / DL) data units, (TX / RX / UL / DL) data, etc. may be based on Fig.18 PPDU transmission / reception signal. Fig.18 The PPDU can be used to send / receive various types of frames. For example, Fig.18 The PPDU may be used for control frames. Examples of control frames may include request to send (RTS), clear to send (CTS), power save poll (PS-poll), BlockACKReq, BlockAck, null data packet (NDP) notification, and trigger frames. For example, Fig.18 The PPDU may be used for management frames. Examples of management frames may include beacon frames, (re)association request frames, (re)association response frames, probe request frames, and probe response frames. For example, Fig.18 The PPDU can be used for data frames. For example, Fig.18 The PPDU may be used to simultaneously transmit at least two or more of a control frame, a management frame, and a data frame.

[0281] Fig.19 An example of a modified transmitting device and / or receiving device of the present specification is shown.

[0282] Figure 1 Each device / STA of sub-graph (a) / (b) can be Fig.19 Modifications shown. Fig.19 The transceiver 630 can be used with Figure 1 The transceivers 113 and 123 are the same. Fig.19 The transceiver 630 may include a receiver and a transmitter.

[0283] Fig.19 The processor 610 can be used with Figure 1 The processors 111 and 121 are the same. Alternatively, Fig.19 The processor 610 can be used with Figure 1 The processing chips 114 and 124 are the same.

[0284] Fig.19 The memory 620 can be connected with Figure 1 The memories 112 and 122 are the same. Alternatively, Fig.19 The memory 620 may be Figure 1 The memories 112 and 122 are different separate external memories.

[0285] Reference Fig.19, power management module 611 manages power for processor 610 and / or transceiver 630. Battery 612 supplies power to power management module 611. Display 613 outputs results processed by processor 610. Keypad 614 receives input to be used by processor 610. Keypad 614 may be displayed on display 613. SIM card 615 may be an integrated circuit for securely storing an International Mobile Subscriber Identity (IMSI) and its associated keys, which are used to identify and authenticate users on mobile telephony devices such as mobile phones and computers.

[0286] Reference Fig.19 The speaker 640 may output a result related to the sound processed by the processor 610. The microphone 641 may receive an input related to the sound to be used by the processor 610.

[0287] Hereinafter, the technical features of channel bonding supported by the STA of the present disclosure will be described.

[0288] For example, in the IEEE 802.11n system, 40 MHz channel bonding can be performed by combining two 20 MHz channels. In addition, 40 / 80 / 160 MHz channel bonding can be performed in the IEEE 802.11ac system.

[0289] For example, a STA may perform channel bonding for a primary 20 MHz channel (P20 channel) and a secondary 20 MHz channel (S20 channel). A backoff count / counter may be used in the channel bonding process. The backoff count value may be selected as a random value and decremented during the backoff interval. Typically, when the backoff count value becomes 0, the STA may attempt to access the channel.

[0290] During the backoff interval, when the P20 channel is determined to be in an idle state and the backoff count value of the P20 channel becomes 0, the STA that performs channel bonding determines whether the S20 channel maintains an idle state for a specific period of time (e.g., point coordination function interframe space (PIFS)). If the S20 channel is in an idle state, the STA may perform bonding on the P20 channel and the S20 channel. That is, the STA may transmit a signal (PPDU) through a 40MHz channel (i.e., a 40MHz bonded channel) including the P20 channel and the S20 channel.

[0291] Fig. 20 An example of channel bonding is shown. Fig. 20 As shown, the primary 20 MHz channel and the secondary 20 MHz channel can be combined into a 40 MHz channel (primary 40 MHz channel) through channel bonding. That is, the bonded 40 MHz channel can include the primary 20 MHz channel and the secondary 20 MHz channel.

[0292] When the channel adjacent to the primary channel is in an idle state, channel bonding can be performed. That is, the primary 20MHz channel, the secondary 20MHz channel, the secondary 40MHz channel, and the secondary 80MHz channel can be bonded in sequence. However, if the secondary 20MHz channel is determined to be in a busy state, channel bonding cannot be performed even if all other secondary channels are in an idle state. In addition, when it is determined that the secondary 20MHz channel is in an idle state and the secondary 40MHz channel is in a busy state, channel bonding can be performed only on the primary 20MHz channel and the secondary 20MHz channel.

[0293] Hereinafter, preamble puncturing supported by STA in the present disclosure will be described.

[0294] For example, in Fig. 20 In the example of , if the primary 20MHz channel, the secondary 40MHz channel, and the secondary 80MHz channel are all in an idle state, but the secondary 20MHz channel is in a busy state, it may not be possible to bind to the secondary 40MHz channel and the secondary 80MHz channel. In this case, the STA may configure a 160MHz PPDU and may perform preamble puncturing on the preamble (e.g., L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, HE-SIG-A, HE-SIG-B, HE-STF, HE-LTF, EHT-SIG, EHT-STF, EHT-LTF, etc.) sent through the secondary 20MHz channel so that the STA can send a signal through the channel in an idle state. In other words, the STA may perform preamble puncturing for some frequency bands of the PPDU. Information about preamble puncturing (e.g., information about the 20 / 40 / 80MHz channels / bands to which puncturing is applied) may be included in the signal field (e.g., HE-SIG-A, U-SIG, EHT-SIG) of the PPDU.

[0295] Hereinafter, technical features of multi-link (ML) supported by STA of the present disclosure will be described.

[0296] The STA (AP and / or non-AP STA) of the present disclosure may support multi-link (ML) communication. ML communication may refer to communication supporting multiple links. Links related to ML communication may include Fig.15 The 2.4 GHz frequency band shown, Fig.16 The 5 GHz frequency band and Fig.17 Channels of the 6 GHz frequency band are shown (e.g., 20 / 40 / 80 / 160 / 240 / 320 MHz channels).

[0297] The multiple links for ML communication may be set in various ways. For example, the multiple links supported by one STA for ML communication may be multiple channels in the 2.4 GHz band, multiple channels in the 5 GHz band, and multiple channels in the 6 GHz band. Alternatively, the multiple links supported by one STA for ML communication may be a combination of at least one channel in the 2.4 GHz band (or 5 GHz / 6 GHz band) and at least one channel in the 5 GHz band (or 2.4 GHz / 6 GHz band). In addition, at least one of the multiple links supported by one STA for ML communication may be a channel to which preamble puncturing is applied.

[0298] The STA may perform ML setting to perform ML communication. The ML setting may be performed based on a management frame or a control frame such as a beacon, a probe request / response, an association request / response, etc. For example, information about the ML setting may be included in an element field included in a beacon, a probe request / response, an association request / response, etc.

[0299] When the ML setting is completed, an enabled link for ML communication may be determined. The STA may perform frame exchange through at least one of the multiple links determined as enabled links. For example, the enabled link may be used for at least one of a management frame, a control frame, and a data frame.

[0300] When a STA supports multiple links, the transceivers supporting each link can operate as a logical STA. For example, a STA supporting two links can be represented as a multi-link device (MLD), including a first STA for a first link and a second STA for a second link. For example, an AP supporting two links can be represented as an AP MLD, including a first AP for the first link and a second AP for the second link. In addition, a non-AP supporting two links can be represented as a non-AP MLD, including a first STA for the first link and a second STA for the second link.

[0301] In the following, more specific features related to the ML setting are described.

[0302] MLD (AP MLD and / or non-AP MLD) can send information about the links that the corresponding MLD can support through ML settings. The link information can be configured in various ways. For example, the information about the link may include 1) information about whether the MLD (or STA) supports simultaneous RX / TX operations, 2) information about the number / upper limit of uplinks / downlinks supported by the MLD (or STA), 3) information about the location / band / resource of the uplinks / downlinks supported by the MLD (or STA), 4) information about the available or preferred frame type (management, control, data, etc.) in at least one uplink / downlink, 5) information about the available or preferred ACK strategy in at least one uplink / downlink, and 6) information about at least one available or preferred service identifier (TID) in at least one uplink / downlink. TID is related to the priority of service data and is represented as eight types of values ​​according to the conventional wireless LAN standard. That is, eight TID values ​​corresponding to four access categories (ACs) (AC_Background (AC_BK), AC_Best Effort (AC_BE), AC_Video (AC_VI), AC_Voice (AC_VO)) according to the conventional WLAN standard may be defined.

[0303] For example, it may be preset that all TIDs are mapped for uplink / downlink. Specifically, if no negotiation is performed through ML settings, if all TIDs are used for ML communication, and if mapping between uplink / downlink and TIDs is negotiated through additional ML settings, the negotiated TIDs may be used for ML communication.

[0304] Through ML setting, multiple links available through sending MLD and receiving MLD related to ML communication can be set, and this can be called "enabled links". "Enabled links" can be called differently by various expressions. For example, it can be called various expressions such as first link, second link, sending link, and receiving link.

[0305] After the ML setting is completed, the MLD may update the ML setting. For example, when it is necessary to update the information about the link, the MLD may send the information about the new link. The information about the new link may be sent based on at least one of a management frame, a control frame, and a data frame.

[0306] In the Extremely High Throughput (EHT) standard discussed after IEEE802.11ax, HARQ is being considered for introduction. When HARQ is introduced, coverage can be extended in a low signal-to-noise ratio (SNR) environment, that is, in an environment where the distance between the transmitting terminal and the receiving terminal is long, and higher throughput can be obtained in a high SNR environment.

[0307] The device described below can be Figure 1 and / or Fig.19 device, and the PPDU can be Fig.18 The device may be an AP or a non-AP STA. The device described below may be an AP multi-link device (MLD) supporting multi-link or a non-AP STA MLD.

[0308] In the Extremely High Throughput (EHT) standard discussed after 802.11ax, a multi-link environment using one or more frequency bands simultaneously is being considered. When a device supports multi-link or multi-link, the device can use one or more frequency bands (e.g., 2.4 GHz, 5 GHz, 6 GHz, 60 GHz, etc.) simultaneously or alternately.

[0309] In the following, although described in the form of multilink, the frequency band may be configured in various other forms. In this specification, terms such as multilink, multilink, etc. may be used, however, for the convenience of the following description, some embodiments may be described based on multilink.

[0310] In the following description, MLD refers to a multi-link device. MLD has one or more connected STAs and one MAC service access point (SAP) connected to the upper link layer (logical link control LLC). MLD may mean a physical device or a logical device. In the following, a device may mean an MLD.

[0311] In the following specification, a transmitting device and a receiving device may refer to an MLD. A first link of a receiving / transmitting device may be a terminal (e.g., STA or AP) that performs signal transmission / reception through a first link included in the receiving / transmitting device. A second link of a receiving / transmitting device may be a terminal (e.g., STA or AP) that performs signal transmission / reception through a second link included in the receiving / transmitting device.

[0312] IEEE802.11be may support two types of multi-link operations. For example, simultaneous transmission and reception (STR) and non-STR operations may be considered. For example, STR may be referred to as asynchronous multi-link operation, and non-STR may be referred to as synchronous multi-link operation. Multi-link may include multiple frequency bands. That is, multi-link may mean a link included in multiple frequency bands, or may mean multiple links included in one frequency band.

[0313] EHT (11be) may consider multi-link technology, where the multi-link may include multiple frequency bands. That is, the multi-link may represent a link of multiple frequency bands, and may represent multiple multi-links within one frequency band. Two types of multi-link operations are being considered. Asynchronous operation that allows simultaneous TX / RX on multiple links and synchronous operation that does not allow simultaneous TX / RX on multiple links are considered. In the following, the ability to allow simultaneous reception and transmission in multiple links is referred to as STR (simultaneous transmission and reception), a STA with STR capability is referred to as STR MLD (multi-link device), and a STA without STR capability is referred to as non-STR MLD.

[0314] Fig.21 An example of the VHT operation element format is shown.

[0315] The operation of VHT STA in BSS is determined by Fig.18 The HT operation element and VHT operation element control.

[0316] In addition, the VHT STA obtains primary channel information from the HT operation element. Fig.21 The VHT Operation Information subfield may be defined as follows.

[0317] [Table 8]

[0318]

[0319] When the Channel Width subfield of the VHT Operation Information subfield is set to 1, the BSS bandwidth may be 80 MHz, 160 MHz, or 80+80 MHz. In this case, the BSS bandwidth based on the value of the Channel Center Frequency Segment (CCFS) 1 subfield may be defined as follows.

[0320] [Table 9]

[0321]

[0322] In this case, CCF (channel center frequency, MHz unit) can be obtained as "channel start frequency + 5*dot11CurrentChannelCenterFrequencyIndex".

[0323] Fig. 22 An example of a multilink element format is shown.

[0324] Fig. 22 The multi-link element may indicate that the STA sending the element is included in the multi-link devices that can operate in a frequency band or operating class or channel other than the channel sending the element.

[0325] in addition, Fig. 22The multilink element may include a multilink control field. The multilink control field may include STARole, STA MAC Address Present, Pairwise Cipher Suite Present, a reserved field, etc.

[0326] in addition, Fig. 22 The multi-link element may include a multi-link connection capability field. The multi-link connection capability field may include AP, PCP, DLS, TDLS, IBSS, reserved field, etc.

[0327] EHT PHY

[0328] Hereinafter, functional blocks of the EHT PHY are described.

[0329] Channelized Harmony Scheme

[0330] 802.11be supports 320MHz and 160+160MHz PPDUs. 802.11be supports 240MHz and 160+80MHz transmissions. Whether 240 / 160+80MHz will be configured by punching holes through the 80MHz channels of 320 / 160+160MHz is undetermined. The 240 / 160+80MHz bandwidth consists of three 80MHz channels, including the primary 80MHz. 802.11be reuses the 802.11ax tone plan for 20 / 40 / 80 / 160 / 80+80MHz PPDUs. In case of 320MHz and 160+160MHz PPDU, 802.11be uses repeated HE160 in OFDMA tone plan. 802.11be 240 / 160+80MHz transmission consists of 3x80MHz segments, and the tone plan of each 80MHz segment is the same as HE80 in 802.11ax. The 160MHz tone plan is duplicated for the non-OFDMA tone plan of 320 / 160+160MHz PPDU. The 160MHz tone plan is undetermined. The 802.11be 320 / 160+160MHz non-OFDMA tone plan uses a repeated tone plan of HE 160. The puncturing design is undetermined. For the non-OFDMA tone plan of 320 / 160+160MHz PPDU, 12 and 11 null tones are deployed at the left and right edges of the 160MHz segment, respectively. In the data portion of the EHT PPDU, 802.11be uses the same subcarrier spacing as in the 802.11ax data portion.

[0331] Resource Unit

[0332] 802.11be should allow one or more RUs to be assigned to a single STA.

[0333] The coding and interleaving scheme for multiple RUs assigned to a single STA is undefined.

[0334] The maximum number of RUs (>1) that can be allocated to a single STA is also undefined.

[0335] L-STF, L-LTF, L-SIG and RL-SIG

[0336] In case of EHT PPDU, L-STF, L-LTF and L-SIG should be transmitted at the beginning of the EHT PPDU.

[0337] In the case of EHT PPDU, the first symbol after L-SIG is BPSK modulated.

[0338] The length field of L-SIG is set to a value N satisfying mod(N,3)=0.

[0339] A phase rotation is applied to the legacy preamble portion of the EHT PPDU.

[0340] The coefficients applied to each 20 MHz channel are undetermined.

[0341] Application to other parts is undetermined.

[0342] The EHT PPDU shall have an RL-SIG field immediately following the L-SIG field, which is a repetition of the L-SIG field.

[0343] U-SIG

[0344] A jointly coded U-SIG having a length of 2 OFDM symbols shall be present in the EHT preamble immediately following the RL-SIG.

[0345] The version-independent field is included in U-SIG. The purpose of the version-independent content is to achieve better coexistence between future 802.11 generations.

[0346] In addition, U-SIB may have some version-dependent fields.

[0347] In the case of extended range mode (when this mode is employed), the size of the U-SIG is undefined.

[0348] The U-SIG is sent using 52 data tones and 4 pilot tones per 20 MHz.

[0349] The U-SIG is modulated in the same manner as in the HE-SIG-A field of 802.11ax.

[0350] Extended range SU mode is undetermined.

[0351] The version-independent bits and the version-dependent bits are included in the U-SIG.

[0352] Fig.23 An implementation of U-SIG is shown.

[0353] Reference Fig.23 , version-independent bits have static positions and bit definitions in various generations / PHY versions. Version-dependent bits may have variable bit definitions in various PHY versions.

[0354] U-SIG shall include the following version-independent fields.

[0355] PHY version identifier: 3 bits

[0356] UL / DL flag: 1 bit

[0357] The PHY version identifier field is one of the version-independent fields of U-SIG.

[0358] Its purpose is to simplify automatic detection of future 802.11 generations. That is, the value of this field is used to identify the exact PHY version starting with 802.11be.

[0359] The exact location of this field is undetermined.

[0360] In the U-SIG field, the version-independent bit part includes the following bits.

[0361] BSS color. The number of bits is undetermined.

[0362] TXOP duration, the number of bits is undetermined.

[0363] EHT-SIG

[0364] An EHT PPDU sent to multiple users shall have a variable MCS and variable length EHT-SIG immediately following the U-SIG.

[0365] The common field and the per-user field shall be present in the EHT-SIG (immediately after the U-SIG) of an EHT PPDU sent to multiple users.

[0366] In special cases, compression modes (e.g., full BW MU-MIMO) are undefined.

[0367] Preamble puncturing

[0368] The 802.11be amendment shall support a preamble puncturing mechanism for EHT PPDUs sent to multiple STAs.

[0369] The 802.11be amendment shall support a preamble puncturing mechanism for EHT PPDUs sent to a single STA.

[0370] EHT MAC

[0371] The functional blocks of the EHT MAC are described in this section.

[0372] The 802.11be amendment shall define a mechanism for an AP to support a STA communicating with another STA.

[0373] Multi-band and multi-channel aggregation and operation

[0374] Capabilities related to multi-band and multi-channel aggregation and operation are described in this section.

[0375] MLD (Multi-Link Device): A device that has one or more attached STAs and has one MAC SAP to LLC, including one MAC data service.

[0376] Note 1-A device can be a logical concept.

[0377] Note 2-There is only one STA undetermined in MLD.

[0378] Note 3-It is undetermined whether the WM MAC addresses of each STA attached to the MLD are the same or different.

[0379] AP Multi-Link Device (AP MLD): MLD, where each STA attached to the MLD is an AP.

[0380] Non-AP Multi-Link Device (Non-AP MLD): MLD, where each STA affiliated to the MLD is a non-AP STA.

[0381] Multi-link operation

[0382] This section describes capabilities related to multilink operation.

[0383] MLD (Multi-Link Device): A device that has one or more attached STAs and has one MAC SAP to LLC, including one MAC data service.

[0384] Note 1-A device can be a logical concept.

[0385] Note 2-There is only one STA undetermined in MLD.

[0386] Note 3-It is undetermined whether the WM MAC addresses of each STA attached to the MLD are the same or different.

[0387] AP Multi-Link Device (AP MLD): MLD, where each STA attached to the MLD is an AP.

[0388] Non-AP Multi-Link Device (Non-AP MLD): MLD, where each STA affiliated to the MLD is a non-AP STA.

[0389] Multilink Settings

[0390] The MLD has a MAC address that identifies the MLD management entity.

[0391] For example, MAC addresses can be used in a multilink setup between a non-AP MLD and an AP MLD.

[0392] The value of the RA / TA field wirelessly transmitted in the MAC header of the frame is the MAC address of the STA attached to the MDL corresponding to the link.

[0393] When the subordinate APs cannot perform simultaneous transmit (TX) / receive (RX) operations (eg, due to close-band interference in the device), the MAC addresses of the subordinate APs within the AP MLD should be different from each other, except when the MAC access nature is undetermined.

[0394] NOTE 1 - It is undetermined whether AP MLD operation is acceptable without simultaneous TX / RX operation.

[0395] 802.11be defines a multi-link setup signaling exchange performed with an AP MLD over a link initiated by a non-AP MLD.

[0396] The ability to swap one or more links during a multi-link setup.

[0397] After the multi-link is successfully set, the AP MLD plays the role of the interface of the non-AP MLD DS.

[0398] Note 1 - Link identification is undetermined.

[0399] Note 2 - Details of non-infrastructure operating modes are not determined.

[0400] An MLD may indicate the capability of simultaneously supporting frame exchanges from a set of dependent STAs to another MLD.

[0401] Defines a new element as a container for advertising and exchanging capability information for multilink setups.

[0402] 802.11be supports mechanisms for multi-link operation.

[0403] The AP attached to the AP MLD may indicate capabilities and operating parameters to one or more STAs of the multi-link device.

[0404] A non-AP STA affiliated to a non-AP MLD may indicate capabilities of one or more non-AP STAs of the non-AP MLD.

[0405] Details of the capabilities and operating parameters of the multi-link device are undetermined.

[0406] An MLD supporting multiple links may advertise, for each pair of links, whether it can simultaneously support transmission on one link and reception on another link.

[0407] Note 1 - The two links exist in different channels.

[0408] NOTE 2 - Whether the ability to advertise whether it can support transmission on one link simultaneously with transmission on another link is defined is undefined.

[0409] 802.11be defines mechanisms for implementing the following multi-link operations.

[0410] Indicates the capabilities and operating parameters of multiple links of the AP MLD.

[0411] Capabilities and operating parameters of multiple links are negotiated while exchanging a single setup signal.

[0412] 802.11be defines a mechanism for canceling an existing multi-link setup protocol.

[0413] After multi-link setup between two MLDs, different GTK / IGTK / BIGTK for different links with different PN spaces are used.

[0414] GTK / IGTK / BIGTK on different links can be transmitted using a 4-step handshake.

[0415] TID to Link Mapping

[0416] 802.11be defines a direction-based TID-to-link mapping mechanism between MLD-enabled links.

[0417] Basically, after multi-link setup, all TIDs are mapped to all setup links.

[0418] The multi-link setup may include TID-to-link mapping negotiation.

[0419] Unless the non-AP MLD indicates during the multi-link setup phase that it is necessary to use the same link set for all TIDs, the TID-to-link mapping may have the same or different link sets for each TID.

[0420] NOTE - The method by which this indication is performed by non-AP MLD is undefined (implicit or explicit).

[0421] The TID-to-link mapping may be updated after multi-link setup through a negotiation that may be initiated by any MLD.

[0422] TBD format

[0423] NOTE - A TID-to-link mapping update may be rejected when the responding MLD cannot accept the update.

[0424] At any point in time, unless admission control is used, a TID should always be mapped to at least one link in the setup.

[0425] A link set up as part of a multi-link setup is defined as enabled when the link is available for frame exchange and at least one TOD is mapped to the link.

[0426] NOTE - The frame exchange of the link varies depending on the power state of the corresponding non-AP STA.

[0427] Management frames are allowed on all enabled links according to the baseline.

[0428] When a TID is mapped to an enabled link set of a non-AP MLD in the UL, the non-AP MLD may use all links in the enabled link set to send data frames in the TID.

[0429] When the TID is mapped to an enabled link set of non-AP MLD in DL:

[0430] The non-AP MLD may retrieve the buffered bus corresponding to the TID on any link in the enabled link set.

[0431] The AP MLD may send the data frame in the TID using all links in the enabled link set according to the existing constraints for frame transmission on the enabled links.

[0432] An example of a constraint is when the STA is in a sleeping state.

[0433] 802.11be defines mechanisms for implementing the following multi-link operations.

[0434] It is a mode of operation in which frames are exchanged simultaneously in one or more links for one or more TIDs.

[0435] It is an operating mode that limits the exchange frames of one or more TIDs in one link at a time.

[0436] A single block acknowledgement protocol is negotiated between two MLDs for a TID that may be sent over one or more links.

[0437] Note - The format of the settings frame is undefined.

[0438] The block protocol for multilink operation is set up using the ADDBA request and ADDBA response frames.

[0439] The established Block ACK protocol allows the exchange of QoS data frames of TIDs aggregated in an A-MPDU between two MLDs on any available link.

[0440] For each block ACK protocol, there is one receive reordering buffer based on the MPDU of the MLD which is the receiver of the QoS data frame of the block ACK protocol.

[0441] The receive reorder buffer operates based on the sequence number space shared between the two MLDs.

[0442] The reception status of the QoS data frame of the TID received on a link may be signaled on the same link and may be signaled on other available links.

[0443] Sequence numbers are allocated in a common sequence number space shared among multiple links of an MLD that can send to a peer MLD's TID over one or more links.

[0444] Power saving

[0445] For each enabled link, frame exchange may be performed when the corresponding non-AP STA of the enabled link is in an awake state.

[0446] Note 1 - The link is enabled when available to exchange frames based on the STA power state.

[0447] Note 2 - When a link is MLD disabled (ie, not enabled), frame exchange cannot take place.

[0448] The AP of the AP MLD may send frames on the link carrying indications of data buffered for transmission on other enabled links.

[0449] The AP MLD may recommend that the non-AP MLD use one or more enabled links.

[0450] The AP's indication may be carried in a broadcast or unicast frame.

[0451] For the link setup between the AP MLD and the non-AP MLD, the non-AP STA operating on the link may send an indication of other non-AP STAs in the same non-AP MLD to the AP operating on the link. The non-AP MLD that has transitioned to the sleep state is in the awake state.

[0452] The non-AP MLD monitors and performs basic operations (eg, traffic indication, BSS parameter update, etc.) on one or more links.

[0453] Each non-AP STA affiliated with a non-AP MLD operating on an enabled link maintains its own power state / mode.

[0454] Multi-link channel access

[0455] 802.11be shall allow the following asynchronous multilink channel access.

[0456] Each STA belonging to the MLD independently performs channel access through its link in order to transmit a frame.

[0457] Downlink frames and uplink frames can be sent simultaneously over multiple links.

[0458] 802.11be should allow MLD with constraints to transmit and receive simultaneously on a pair of links and operate over the pair of links.

[0459] The signal of this constraint is undetermined.

[0460] Multi-AP Operation

[0461] This section describes the capabilities related to multi-AP operation.

[0462] Joint NDP Probe

[0463] 802.11be provides a joint NDP detection scheme as an optional mode for multi-AP systems.

[0464] In a multi-AP system, a sequential detection scheme may also be used in which each AP independently and sequentially sends an NDP while the detection cycles of each AP do not overlap.

[0465] The joint NDP sounding scheme for multi-AP systems where the total number of antennas in the APs is less than or equal to 8 enables all antennas in all LTF tones and uses the 802.11ax P matrix in the OFDM symbols.

[0466] Although there are existing APs that support two or more frequency bands at the same time, the APs are actually only physically located in the same location and are used by being established as separate BSSs. Therefore, the AP communicates with each STA for each BSS.

[0467] Currently, 802.11ax has extended the supported transmission band to 6 GHz, and 802.11be, which is currently being standardized, also plans to support the 6 GHz band. As has been done so far, devices supporting 5 GHz and 6 GHz can operate antennas / RF chains dedicated to each band, but due to device space constraints, a shared antenna / RF chain capable of supporting both 5 GHz and 6 GHz can be configured.

[0468] As more and more APs operating 5 GHz and 6 GHz are deployed, and STAs also operate shared antennas / RF chains capable of supporting 5 GHz and 6 GHz, flexible and efficient transmission and reception requires a frequency band and channel negotiation process between the APs and STAs.

[0469] This specification proposes a frequency band negotiation process for each antenna / RF chain during transmission and reception between a STA and an AP using a shared antenna / RF chain capable of supporting multiple frequency bands. To this end, the present disclosure also proposes a method for exchanging information about the antenna / RF chain of the AP and the STA with each other during the association time.

[0470] Although the frequency band is described in the form of multi-link in the specification described below, the frequency band can be configured in various forms. That is, although multi-band, multi-link, etc. can be used in this specification, some examples are described based on multi-link for convenience of description below.

[0471] Although the number of links in the multi-link environment is indicated as two in the specification described below, it is also applicable to the case where the number of links is greater than 2. Hereinafter, for convenience of description, some examples are described based on a multi-link environment where the number of links is 2.

[0472] In the following description, MLD refers to a multi-link device. An MLD has one or more associated STAs and has one MAC service access point (SAP) connected to an upper link layer (logical link control (LLC)). An MLD may refer to a physical device or a logical device.

[0473] 1. Operation process

[0474] It is necessary to first exchange information about the shared antenna / RF chain between the AP MLD and the non-AP MLD in the AP MLD and non-AP MLD association process or in a subsequent process. This information can be indicated by appropriate elements in the association request / response exchange process, or can also be indicated in advance through a neighbor report or beacon frame.

[0475] Fig.24 and Fig.25 An embodiment of an operating band negotiation request frame format is shown.

[0476] When the AP MLD and the non-AP MLD know the information about each other's antenna / RF chain through the above method, if the non-AP MLD using the shared antenna / RF chain desires to change the operating band and channel of at least one antenna / RF chain, the non-AP MLD can perform operating band negotiation with the AP MLD. Fig.24 Alternatively, when assigning a unique ID to the operating band and channel of the AP MLD, it may be as follows: Fig.25 When the AP MLD desires to change the antenna / RF chain of a non-AP MLD, the AP may perform operating band negotiation in the same manner.

[0477] Fig.24 and Fig.25The operating band negotiation request frame may include the following information.

[0478] RA: Receiver address.

[0479] TA: Transmitter address.

[0480] Capability information: optional capability information

[0481] New Operation Class: Includes information about the operation class for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification can be used.

[0482] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0483] Maximum NSS: Indicates the number of spatial streams to be operated in the frequency band and channel (i.e., link) corresponding to the new operation class and new channel number defined above. The maximum number of SSs (i.e., maximum NSS) may be determined at the MLD level. For example, the maximum number of streams that can be operated by the MLD may be determined based on the number of antennas included in all STAs included in the MLD. Basically, each link supported by the MLD may be operated by the STAs included in the MLD. However, the maximum NSS that can be operated in each link may not be limited to the number of antennas of the STAs operating on each link.

[0484] For example, the MLD may include a first STA and a second STA, the first STA may operate on a first link, and the second STA may operate on a second link. Herein, when the first STA may operate two SSs and the second STA may operate two SSs, since the MLD may operate at most four SSs, the maximum NSS is 4. Herein, the first STA may operate only two SSs, but the MLD may share the antenna of the second STA and use it for the first link. Therefore, the maximum NSS that can be operated on the first link based on antenna sharing is ultimately equal to the maximum NSS of the MLD. Similarly, the maximum NSS that can be operated on the second link is equal to the maximum NSS of the MLD.

[0485] Supported band and channel information: If there is an already negotiated ID (eg, link ID) for the band or channel the AP operates on, the ID may be used.

[0486] Fig.26 An embodiment of an operating band negotiation response frame format is shown.

[0487] Reference Fig.26 , upon receiving the request frame, the AP MLD may respond using an operating band negotiation frame or in a manner similar to that in the existing ACK frame. Fig.26The configuration of the operating band negotiation response frame is shown. The operating band negotiation response frame may include the following information.

[0488] New Operation Class: Includes information about the operation class for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification can be used.

[0489] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0490] Maximum NSS: Indicates the number of spatial streams to be operated in the frequency band and channel corresponding to the new operation class and new channel number defined above. The maximum number of SSs (i.e., maximum NSS) may be determined at the MLD level. For example, the maximum number of streams that can be operated by the MLD may be determined based on the number of antennas included in all STAs included in the MLD. Basically, each link supported by the MLD may be operated by the STAs included in the MLD. However, the maximum NSS that can be operated in each link may not be limited to the number of antennas of the STAs operating on each link.

[0491] For example, the MLD may include a first STA and a second STA, the first STA may operate on a first link, and the second STA may operate on a second link. Herein, when the first STA may operate two SSs and the second STA may operate two SSs, since the MLD may operate at most four SSs, the maximum NSS is 4. Herein, the first STA may operate only two SSs, but the MLD may share the antenna of the second STA and use it for the first link. Therefore, the maximum NSS that can be operated on the first link based on antenna sharing is ultimately equal to the maximum NSS of the MLD. Similarly, the maximum NSS that can be operated on the second link is equal to the maximum NSS of the MLD.

[0492] BSSID: Indicates the BSSID of the BSS to be established when establishing a new BSS. If the same BSSID is used, this information can be omitted.

[0493] Beacon Interval: Indicates the beacon interval in the defined channel. This information can be omitted if the same beacon interval is used.

[0494] EDCA Interval: If an EDCA / scheduled access only interval exists in the defined channel, time information about the interval is indicated.

[0495] Fig. 27 An implementation of the EHT Capability Element format is shown.

[0496] Reference Fig. 27, STA MLD may transmit capability information to AP MLD in the form of an element instead of a determined frame. In the existing specification, AP MLD and non-AP MLD exchange capability information and operation information through HT capability / operation, VHT capability / operation, and HE capability / operation elements. Similarly, in EHT, an EHT capability / operation element may be designed, and the band negotiation process may be performed through this element. Fig. 27 As shown, the EHT capability element to be designed in the future may include a field capable of indicating the operation class and channel information and the maximum NSS, so as to negotiate the frequency band and channel change of the antenna / RF chain of the non-AP MLD.

[0497] 2. Implementation Method

[0498] Fig.28 is a flow chart illustrating an example of an operating band switching process.

[0499] Fig.29 An example of an operating band switching process is shown.

[0500] When the AP MLD operates multiple bands of 5 GHz and 6 GHz and knows that the non-AP MLD1 can use the shared antenna / RF channel, the AP MLD can perform operating band negotiation with the non-AP MLD1. The non-AP MLD1 exchanges antenna / RF chain information (e.g., the number of shared antennas / RF chains, supportable frequency bands, etc.) in the process of associating with the AP MLD. The non-AP MLD1, knowing that the AP MLD supports 6 GHz, expects to operate the shared antenna / RF chain in 6 GHz, and switches from 5 GHz to 6 GHz after exchanging operating band negotiation request / response frames. The AP MLD updates the information about STA1, and then performs transmission and reception on the switched 6 GHz band. Fig.28 and Fig.29 A series of processes are shown in FIG. In addition, the AP MLD may first send an operating band negotiation request to adjust the frequency band of the antenna / RF chain receiving the non-AP MLD1.

[0501] Fig.30 is a flow chart illustrating another example of an operating band switching process.

[0502] Fig.31 Another example of an operating band switching process is shown.

[0503] The same scenario can be applied to STA 2 that supports multiple frequency bands. When the AP operates multiple frequency bands of 5 GHz and 6 GHz and knows that STA 2 can use a shared antenna / RF chain, the AP can perform an operating frequency band negotiation with STA 2. STA 2 exchanges antenna / RF chain information (e.g., the number of shared antennas / RF chains, supportable frequency bands, etc.) during the association process with the AP. When STA 2, knowing that the AP supports 6 GHz, desires to operate the shared antenna / RF chain in 6 GHz, STA 2 exchanges operating frequency band negotiation request / response frames and then switches from 5 GHz to 6 GHz. The AP updates information about STA 2 and then performs multi-band data transmission and reception in the 5 GHz and 6 GHz frequency bands. Fig.30 and Fig.31 A series of processes are shown in FIG. In addition, the AP may first send an operating band negotiation request to adjust the frequency band of the antenna / RF chain of the receiving STA.

[0504] 3. Operation process

[0505] Fig.32 An implementation of a frequency band switch announcement element is shown.

[0506] Reference Fig.32 , the frequency band switch announcement element may include the following information.

[0507] Frequency band information: includes information about the frequency band to be switched.

[0508] Channel Switch Mode: is a field included in the existing (extended) Channel Switch Announcement element, and prevents the STA receiving this information from transmitting until bandwidth occurs.

[0509] New Operation Class: Includes information about the operation class used for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0510] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0511] Maximum NSS: Indicates the number of spatial streams to be operated in the frequency band and channel corresponding to the new operation class and new channel number defined above. The maximum number of SSs (i.e., maximum NSS) may be determined at the MLD level. For example, the maximum number of streams that can be operated by the MLD may be determined based on the number of antennas included in all STAs included in the MLD. Basically, each link supported by the MLD may be operated by the STAs included in the MLD. However, the maximum NSS that can be operated in each link may not be limited to the number of antennas of the STAs operating on each link.

[0512] For example, the MLD may include a first STA and a second STA, the first STA may operate on a first link, and the second STA may operate on a second link. Herein, when the first STA may operate two SSs and the second STA may operate two SSs, since the MLD may operate at most four SSs, the maximum NSS is 4. Herein, the first STA may operate only two SSs, but the MLD may share the antenna of the second STA and use it for the first link. Therefore, the maximum NSS that can be operated on the first link based on antenna sharing is ultimately equal to the maximum NSS of the MLD. Similarly, the maximum NSS that can be operated on the second link is equal to the maximum NSS of the MLD.

[0513] BSSID: Indicates the BSSID of the new BSS to be established when establishing a new BSS. If the same BSSID is used, this information can be omitted.

[0514] Beacon Interval: Indicates the beacon interval in the defined channel. This information can be omitted if the same beacon interval is used.

[0515] EDCA Interval: If an EDCA / scheduled access only interval exists in the defined channel, time information about the interval is indicated.

[0516] Supported Rates: Indicates the rates that can be supported in the defined channel.

[0517] Count: Indicates the number of beacons remaining until the application-defined switch.

[0518] Information other than the above may also be included in the element. For example, MLD may be configured as follows Fig.32 The frequency band switch notification element shown. This element is an example of a frequency band switch notification element, and the length of each field may vary. In addition, additional information may be included or unnecessary information may be omitted.

[0519] Fig.33 An implementation of a frequency band switch announcement element is shown.

[0520] Reference Fig.33 , an implementation in which all information of the frequency band to be switched after the frequency band switching is included in one element is also possible. At least one piece of frequency band information may be included in a field called a frequency band switching list. The subfields in the list may be indicated by the frequency band switching control field.

[0521] 4. Implementation Method

[0522] 1)5GHz RF×4->5GHz RF×2+6GHz RF×2

[0523] The congestion levels in the 5 GHz and 6 GHz bands may vary significantly depending on the capabilities of the MLD associated with the AP MLD. Therefore, there may be situations where an AP with a shared RF and operating in the 5 GHz band desires to switch some RFs to 6 GHz.

[0524] Fig.34 An implementation of a frequency band switching process is shown.

[0525] Reference Fig.34 When the AP MLD with shared RF wants to switch some RFs to different frequency bands, it can notify the associated STA MLDs through the band switching notification element. The STA MLD 1 using the shared RF switches to 6 GHz and then performs a transmission / reception process.

[0526] When STA MLD 2 also has a shared RF and can use two or more different frequency bands at the same time (supports multi-band), STA MLD 2 having received this can determine whether to perform band switching based on the information included in the band switching announcement element. When it is determined to perform transmission and reception by multi-band after switching only one RF, STA MLD 2 switches one RF from the 5 GHz band to the 6 GHz band and then performs transmission and reception processing.

[0527] like Fig.34 As shown in the embodiment of the present invention, the STA MLD that desires to perform band switching needs to notify the AP of this, but the AP MLD may be allowed to attempt DL transmission. This operation may be performed by sending a random frame or a QoS null frame in the band that the STA MLD 2 desires to switch (in this embodiment, 6 GHz). However, in this specification, this method is not limited to this.

[0528] In the following, reference is made to Figures 21 to 34 The above-mentioned embodiments are described.

[0529] Fig.35 An embodiment of a method performed in a non-AP (Access Point) STA (Station) MLD (Multi-Link Device) is shown.

[0530] Reference Fig.35 , the non-AP STA MLD may send a negotiation frame (S3510). For example, the non-AP STA MLD may send a negotiation frame including first maximum number of spatial streams (NSS) information to the AP MLD through the first link.

[0531] For example, the first maximum NSS information may be the maximum number of flows operated by the non-AP STA MLD on the first link.

[0532] For example, the negotiation frame may also include information related to antenna sharing.

[0533] For example, the negotiation frame may also include information related to operating band switching.

[0534] For example, the operating band negotiation request frame may include the following information.

[0535] RA: Receiver address.

[0536] TA: Transmitter address.

[0537] Capability information: optional capability information

[0538] New Operation Class: Includes information about the operation class for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification can be used.

[0539] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0540] Maximum NSS: Indicates the number of spatial streams to be operated in the frequency band and channel (i.e., link) corresponding to the new operation class and new channel number defined above. The maximum number of SSs (i.e., maximum NSS) may be determined at the MLD level. For example, the maximum number of streams that can be operated by the MLD may be determined based on the number of antennas included in all STAs included in the MLD. Basically, each link supported by the MLD may be operated by the STAs included in the MLD. However, the maximum NSS that can be operated in each link may not be limited to the number of antennas of the STAs operating on each link.

[0541] For example, the MLD may include a first STA and a second STA, the first STA may operate on a first link, and the second STA may operate on a second link. Herein, when the first STA may operate two SSs and the second STA may operate two SSs, since the MLD may operate at most four SSs, the maximum NSS is 4. Herein, the first STA may operate only two SSs, but the MLD may share the antenna of the second STA and use it for the first link. Therefore, the maximum NSS that can be operated on the first link based on antenna sharing is ultimately equal to the maximum NSS of the MLD. Similarly, the maximum NSS that can be operated on the second link is equal to the maximum NSS of the MLD.

[0542] Supported band and channel information: If there is an already negotiated ID (eg, link ID) for the band or channel the AP operates on, the ID may be used.

[0543] The non-AP STA MLD may receive a negotiation response frame (S3520). For example, the non-AP STA MLD may receive a negotiation response frame from the AP MLD through the first link in response to the negotiation frame. For example, the operating band negotiation response frame may include the following information.

[0544] New Operation Class: Includes information about the operation class for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification can be used.

[0545] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0546] Maximum NSS: Indicates the number of spatial streams to be operated in the frequency band and channel corresponding to the new operation class and new channel number defined above. The maximum number of SSs (i.e., maximum NSS) may be determined at the MLD level. For example, the maximum number of streams that can be operated by the MLD may be determined based on the number of antennas included in all STAs included in the MLD. Basically, each link supported by the MLD may be operated by the STAs included in the MLD. However, the maximum NSS that can be operated in each link may not be limited to the number of antennas of the STAs operating on each link.

[0547] For example, the MLD may include a first STA and a second STA, the first STA may operate on a first link, and the second STA may operate on a second link. Herein, when the first STA may operate two SSs and the second STA may operate two SSs, since the MLD may operate at most four SSs, the maximum NSS is 4. Herein, the first STA may operate only two SSs, but the MLD may share the antenna of the second STA and use it for the first link. Therefore, the maximum NSS that can be operated on the first link based on antenna sharing is ultimately equal to the maximum NSS of the MLD. Similarly, the maximum NSS that can be operated on the second link is equal to the maximum NSS of the MLD.

[0548] BSSID: Indicates the BSSID of the BSS to be established when establishing a new BSS. If the same BSSID is used, this information can be omitted.

[0549] Beacon Interval: Indicates the beacon interval in the defined channel. This information can be omitted if the same beacon interval is used.

[0550] EDCA Interval: If an EDCA / scheduled access only interval exists in the defined channel, time information about the interval is indicated.

[0551] The non-AP STA MLD may receive data (S3530). For example, the non-AP STA MLD may receive data from the AP MLD through the first link based on the first maximum NSS information. That is, the AP MLD may send data through the first link using a spatial stream that does not exceed the first maximum NSS of the non-AP STA MLD.

[0552] For example, the non-AP STA MLD may send a negotiation frame including a second maximum number of spatial streams (NSS) information to the AP MLD via the second link, receive a negotiation response frame from the AP MLD via the second link in response to the negotiation frame, and receive data from the AP MLD via the second link based on the second maximum NSS information. For example, the second maximum NSS information may be the maximum number of streams operated by the non-AP MLD on the second link.

[0553] For example, the maximum (Max) NSS information may be NSS capability information at the link level. That is, there may be a maximum NSS capability for each link. The MLD may support multiple links, and each link may have a maximum NSS capability. The MLD may include multiple STAs, and the STA may operate on each link.

[0554] For example, when the MLD includes a first STA and a second STA and supports a first link and a second link, the first STA may operate on the first link and the second STA may operate on the second link. For example, the maximum NSS capability of the first link may be greater than the number of antennas of the first STA. For example, the second STA may assist the reception / transmission of the first STA through antenna sharing. The maximum NSS capability may change dynamically. For example, the maximum NSS capability of the first link may be determined based on the antenna of the first STA and the sharable antenna of the second STA. The number of sharable antennas of the second STA may vary, and there may be a situation where some antennas of the first STA are shared or unavailable to another STA. Therefore, the maximum NSS capability may change dynamically.

[0555] Since the maximum NSS capability information is transmitted / received, an advantage can be obtained in preventing a problem in which the MLD cannot receive all flows because flows having at least NSS capability are transmitted on a specific link.

[0556] Fig.36 An embodiment of a method performed in an AP MLD is shown.

[0557] Reference Fig.36 , the non-AP STA MLD may send a negotiation frame (S3610). For example, the AP STA MLD may receive a negotiation frame including first maximum number of spatial streams (NSS) information from the non-AP STA MLD through a first link.

[0558] For example, the first maximum NSS information may be the maximum number of flows operated by the non-AP STA MLD on the first link.

[0559] For example, the negotiation frame may also include information related to antenna sharing.

[0560] For example, the negotiation frame may also include information related to operating band switching.

[0561] For example, the operating band negotiation request frame may include the following information.

[0562] RA: Receiver address.

[0563] TA: Transmitter address.

[0564] Capability information: optional capability information

[0565] New Operation Class: Includes information about the operation class for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification can be used.

[0566] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0567] Maximum NSS: Indicates the number of spatial streams to operate in the frequency band and channel (ie, link) corresponding to the new operating class and new channel number defined above.

[0568] Supported band and channel information: If there is an already negotiated ID (eg, link ID) for the band or channel the AP operates on, the ID may be used.

[0569] The AP MLD may send a negotiation response frame (S3620). For example, the AP MLD may send a negotiation response frame to the non-AP STA MLD through the first link in response to the negotiation frame. For example, the operating band negotiation response frame may include the following information.

[0570] New Operation Class: Includes information about the operation class for band switching. The country element and operation class values ​​specified in the 802.11 baseline specification can be used.

[0571] New Channel Number: Includes information about the operating channel after the band switch. The country element and operation class values ​​specified in the 802.11 baseline specification may be used.

[0572] Maximum NSS: Indicates the number of spatial streams to operate in the frequency band and channel corresponding to the new operating class and new channel number defined above.

[0573] BSSID: Indicates the BSSID of the BSS to be established when establishing a new BSS. If the same BSSID is used, this information can be omitted.

[0574] Beacon Interval: Indicates the beacon interval in the defined channel. This information can be omitted if the same beacon interval is used.

[0575] EDCA Interval: If an EDCA / scheduled access only interval exists in the defined channel, time information about the interval is indicated.

[0576] The AP MLD may send data (S3630). For example, the AP MLD may send data from the non-AP STA MLD through the first link based on the first maximum NSS information. That is, the AP MLD may send data through the first link using a spatial stream that does not exceed the first maximum NSS of the non-AP STA MLD.

[0577] For example, the non-AP STA MLD may send a negotiation frame including a second maximum number of spatial streams (NSS) information to the AP MLD via the second link, receive a negotiation response frame from the AP MLD via the second link in response to the negotiation frame, and receive data from the AP MLD via the second link based on the second maximum NSS information. For example, the second maximum NSS information may be the maximum number of streams operated by the non-AP MLD on the second link.

[0578] For example, the maximum (Max) NSS information may be NSS capability information at the link level. That is, there may be a maximum NSS capability for each link. The MLD may support multiple links, and each link may have a maximum NSS capability. The MLD may include multiple STAs, and the STA may operate on each link.

[0579] For example, when the MLD includes a first STA and a second STA and supports a first link and a second link, the first STA may operate on the first link and the second STA may operate on the second link. For example, the maximum NSS capability of the first link may be greater than the number of antennas of the first STA. For example, the second STA may assist the reception / transmission of the first STA through antenna sharing. The maximum NSS capability may change dynamically. For example, the maximum NSS capability of the first link may be determined based on the antenna of the first STA and the sharable antenna of the second STA. The number of sharable antennas of the second STA may vary, and there may be a situation where some antennas of the first STA are shared or unavailable to another STA. Therefore, the maximum NSS capability may change dynamically.

[0580] Since the maximum NSS capability information is transmitted / received, an advantage can be obtained in preventing a problem in which the MLD cannot receive all flows because flows having at least NSS capability are transmitted on a specific link.

[0581] Fig.35 and Fig.36 Some of the detailed steps shown in the examples may not be necessary and may be omitted. Fig.35 and Fig.36 Other steps may be added to the steps shown, and the order of the steps may be changed. Some of the above steps may have independent technical meanings.

[0582] The above technical features of this specification can be applied to various devices and methods. For example, the above technical features of this specification can be applied to various devices and methods. Figure 1 and / or Fig.19 For example, the above technical features of this specification can only be applied to Figure 1 and / or Fig.19 For example, the above technical features of this specification can be based on Figure 1 The processing chips 114 and 124 can be implemented, or based on Figure 1 The processors 111 and 121 and the memories 112 and 122 can be implemented, or based on Fig.19 The device of the present specification includes a processor 610 and a memory 620. For example, the device of the present specification includes a memory and a processor operatively connected to the memory. The processor is configured to: send a negotiation frame including first maximum number of spatial streams (NSS) information to the AP MLD through a first link; and receive a negotiation response frame from the AP MLD through the first link in response to the negotiation frame.

[0583] The technical features of this specification can be implemented based on a computer readable medium (CRM). For example, the CRM proposed in this specification is at least one computer readable medium, which includes instructions executed by at least one processor of a non-access point (AP) STAMLD of a wireless local area network (WLAN) system. The CRM can store instructions to perform the following operations: send a negotiation frame including first maximum number of spatial streams (NSS) information to the APMLD via a first link; and receive a negotiation response frame from the APMLD via the first link in response to the negotiation frame.

[0584] The instructions stored in the CRM of this specification can be executed by at least one processor. At least one processor associated with the CRM of this specification can be Figure 1 The processors 111 and 121 or the processing chips 114 and 124 or Fig.19 In addition, the CRM of this specification may be Figure 1 The memories 112 and 122 or Fig.19 memory 620 or a separate external memory / storage medium / disk, etc.

[0585] The above technical features of this specification are applicable to various applications or business models. For example, the above technical features can be applied to wireless communications of devices supporting artificial intelligence (AI).

[0586] Artificial intelligence refers to the field of study regarding artificial intelligence or methods of creating artificial intelligence, while machine learning refers to the field of study regarding methods of defining and solving various problems in the field of artificial intelligence. Machine learning is also defined as algorithms that improve the performance of operations through stable experience of operations.

[0587] An artificial neural network (ANN) is a model used in machine learning and may refer to an overall problem-solving model that includes artificial neurons (nodes) that form a network by combining synapses. An artificial neural network may be defined by the connection pattern between neurons in different layers, a learning process that updates model parameters, and an activation function that generates an output value.

[0588] The artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer includes one or more neurons, and the artificial neural network may include synapses connecting neurons. In the artificial neural network, each neuron may output a function value of an activation function of an input signal, a weight, and a bias input through the synapse.

[0589] Model parameters refer to parameters determined by learning and include weights of synaptic connections and biases of neurons. Hyperparameters refer to parameters set in a machine learning algorithm prior to learning and include learning rate, number of iterations, mini-batch size, and initialization function.

[0590] Learning an artificial neural network can be aimed at determining model parameters for minimizing a loss function. The loss function can be used as an index for determining the optimized model parameters during learning an artificial neural network.

[0591] Machine learning can be categorized into supervised learning, unsupervised learning, and reinforcement learning.

[0592] Supervised learning refers to a method of training an artificial neural network when labels are given for training data, wherein the labels may indicate the correct answer (or result value) that the artificial neural network needs to infer when the training data is input to the artificial neural network. Unsupervised learning may refer to a method of training an artificial neural network when no labels are given for training data. Reinforcement learning may refer to a training method of an agent defined in a training environment to select actions or action sequences to maximize the cumulative reward in each state.

[0593] Machine learning implemented using a deep neural network (DNN) including multiple hidden layers in an artificial neural network is called deep learning, and deep learning is a part of machine learning. Hereinafter, machine learning is explained as including deep learning.

[0594] The above technical features can be applied to wireless communication of robots.

[0595] A robot may refer to a machine that automatically processes or operates a given task with its own capabilities. Specifically, a robot that has the function of recognizing an environment and autonomously making judgments to perform operations may be referred to as an intelligent robot.

[0596] Robots can be classified into industrial, medical, household, military robots, etc. according to their uses or fields. Robots can include actuators or drives, which include motors to perform various physical operations (e.g., move robot joints). In addition, mobile robots can include wheels, brakes, propellers, etc. in the drive to travel on the ground or fly in the air through the drive.

[0597] The above technical features can be applied to devices supporting extended reality.

[0598] Extended reality refers collectively to virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology is a computer graphics technology that provides real-world objects and backgrounds only in CG images, AR technology is a computer graphics technology that provides virtual CG images on real object images, and MR technology is a computer graphics technology that provides virtual objects mixed and combined with the real world.

[0599] MR technology is similar to AR technology in that real objects and virtual objects are displayed together. However, in AR technology, virtual objects are used as a supplement to real objects, while in MR technology, virtual objects and real objects are used as equal.

[0600] XR technology may be applied to head mounted displays (HMDs), heads up displays (HUDs), mobile phones, tablet PCs, laptop computers, desktop computers, TVs, digital signage, etc. Devices to which XR technology is applied may be referred to as XR devices.

[0601] The claims described in this specification can be combined in various ways. For example, the technical features of the method claims of this specification can be combined to be implemented as a device, and the technical features of the device claims of this specification can be combined to be implemented by a method. In addition, the technical features of the method claims of this specification and the technical features of the device claims can be combined to be implemented as a device, and the technical features of the method claims of this specification and the technical features of the device claims can be combined to be implemented by a method.

Claims

1. A method executed in a non-access point (AP) station (STA) multi-link device (MLD) of a wireless local area network (WLAN) system, the method comprising the following steps: Sending a negotiation frame including first maximum spatial stream number NSS information to the AP MLD through the first link, The first maximum NSS information is determined based on the number of antennas included in all STAs included in the non-AP STA MLD; and A negotiation response frame is received from the AP MLD through the first link in response to the negotiation frame.

2. The method according to claim 1, further comprising the following steps: receiving data from the AP MLD through the first link based on the first maximum NSS information, The first maximum NSS information is the maximum number of flows operated by the non-AP MLD on the first link.

3. The method according to claim 1, further comprising the steps of: Sending a negotiation frame including the first maximum NSS information to the AP MLD through a second link; receiving a negotiation response frame from the AP MLD via the second link in response to the negotiation frame; as well as Data is received from the AP MLD through the second link based on the first maximum NSS information.

4. The method according to claim 3, wherein: The first maximum NSS information is operated by a non-AP MLD on the second link.

5. The method according to claim 1, wherein: The negotiation frame also includes information related to antenna sharing.

6. The method according to claim 1, wherein: The negotiation frame also includes information related to operating frequency band switching.

7. A non-access point (AP) station (STA) multi-link device (MLD) used in a wireless local area network (WLAN) system, the non-AP (STA) station (MLD) comprising: a transceiver that sends and receives radio signals; as well as a processor operatively coupled to the transceiver, wherein the processor is configured to: Sending a negotiation frame including first maximum spatial stream number NSS information to the AP MLD through the first link, The first maximum NSS information is determined based on the number of antennas included in all STAs included in the non-AP STA MLD; and A negotiation response frame is received from the AP MLD through the first link in response to the negotiation frame.

8. The non-AP STA MLD according to claim 7, in, The processor is further configured to receive data from the APMLD through the first link based on the first maximum NSS information, The first maximum NSS information is the maximum number of flows operated by the non-AP MLD on the first link.

9. The non-AP STA MLD according to claim 7, wherein the non-AP STA MLD is further configured to: Sending a negotiation frame including the first maximum NSS information to the AP MLD through a second link; receiving a negotiation response frame from the AP MLD via the second link in response to the negotiation frame; and Data is received from the AP MLD through the second link based on the first maximum NSS information.

10. The non-AP STA MLD according to claim 9, wherein: The first maximum NSS information is operated by a non-AP MLD on the second link.

11. The non-AP STA MLD according to claim 7, wherein: The negotiation frame also includes information related to antenna sharing.

12. The non-AP STA MLD according to claim 7, wherein: The negotiation frame also includes information related to operating frequency band switching.

13. A method executed in an access point multi-link device (MLD) of a wireless local area network (WLAN) system, the method comprising the following steps: receiving a negotiation frame including first maximum spatial stream number NSS information from a non-AP station STA MLD through a first link, The first maximum NSS information is determined based on the number of antennas included in all STAs included in the non-AP STA MLD; and In response to the negotiation frame, a negotiation response frame is sent to the non-AP STA MLD through the first link.

14. An access point AP multi-link device MLD used in a wireless local area network WLAN system, the AP MLD comprising: a transceiver that sends and receives radio signals; as well as a processor operatively coupled to the transceiver, wherein the processor is configured to: receiving a negotiation frame including first maximum spatial stream number NSS information from a non-AP station STA MLD through a first link, The first maximum NSS information is determined based on the number of antennas included in all STAs included in the non-AP STA MLD; and In response to the negotiation frame, a negotiation response frame is sent to the non-AP STA MLD through the first link.

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