CN117099472A

CN117099472A - Method and apparatus for establishing multilink based on status code reception in wireless LAN system

Info

Publication number: CN117099472A
Application number: CN202280023942.4A
Authority: CN
Inventors: 张仁善; 崔镇洙; 金娜明; 白善熙
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2021-03-24
Filing date: 2022-03-21
Publication date: 2023-11-21

Abstract

A method and apparatus for establishing a multilink based on status code reception in a wireless LAN system are provided. Specifically, the receiving MLD transmits a first association request frame to the transmitting MLD via the first link. The receiving MLD receives the first association response frame from the transmitting MLD via the first link. The first association response frame includes a first ML element. The first ML element includes a profile field of the second transmitting STA. The profile field of the second transmitting STA includes a status code. The status code includes information indicating that the establishment of ML has failed because the second link is allowed but the first link is not allowed.

Description

Method and apparatus for establishing multilink based on status code reception in wireless LAN system

Technical Field

The present specification relates to multilink operation in a wireless LAN system, and more particularly, to a method and apparatus for receiving whether to establish multilink based on a status code.

Background

Wireless Local Area Networks (WLANs) have been improved in various ways. For example, the IEEE 802.11ax standard proposes an improved communication environment using Orthogonal Frequency Division Multiple Access (OFDMA) and downlink multi-user multiple input multiple output (DL MU MIMO) techniques.

The present specification proposes technical features that can be utilized in a new communication standard. For example, the new communication standard may be the very high throughput (EHT) standard currently in question. The EHT standard may use newly proposed increased bandwidth, enhanced PHY layer protocol data unit (PPDU) structure, enhanced sequences, hybrid automatic repeat request (HARQ) scheme, etc. The EHT standard may be referred to as the IEEE 802.11be standard.

In the new wireless LAN standard, an increased number of spatial streams may be used. In this case, in order to properly use the increased number of spatial streams, it may be necessary to improve signaling techniques in the WLAN system.

Disclosure of Invention

Technical problem

The present specification proposes a method and apparatus for transmitting and receiving an entire profile within an ML element in a WLAN system.

Technical solution

Examples of the present specification propose a method for receiving whether to establish a multilink based on a status code.

The present embodiment may be performed in a network environment supporting a next generation WLAN system (IEEE 802.11be or EHT WLAN system). The next generation wireless LAN system is a WLAN system enhanced with respect to the 802.11ax system, and thus can satisfy backward compatibility with the 802.11ax system.

The present embodiments propose methods and apparatus for placing and transmitting status codes during multi-link establishment between an AP MLD and a non-AP MLD. The status code means information indicating whether a specific link is accepted or rejected in the multilink establishment. Here, the transmitting MLD may correspond to an AP MLD, and the receiving MLD may correspond to a non-AP MLD. If the non-AP STA is a first receiving STA, a first transmitting STA connected to the first receiving STA through a first link may be referred to as a peer-to-peer AP, a second transmitting STA and a third transmitting STA connected through different links may be referred to as other APs, and a second receiving STA and a third receiving STA connected through different links may be referred to as other non-AP STAs.

A receiving multi-link device (MLD) transmits a first association request frame to a transmitting MLD over a first link.

The receiving MLD receives a first association response frame from the transmitting MLD over the first link.

The transmitting MLD includes a first transmitting Station (STA) operating on a first link and a second transmitting STA operating on a second link. The receiving MLD includes a first receiving STA operating on a first link and a second receiving STA operating on a second link.

The first association response frame includes a first multi-link (ML) element. The first ML element includes a profile field of the second transmitting STA. The profile field of the second transmitting STA includes a status code. The status code includes information that the ML setup has failed because the second link is allowed but the first link is not allowed. The status code may be set to decoded_multi-link setup_failed.

At this time, a first link that transmits the first association request/response frame may be named a transmission link (t_link), and a second link and a third link that do not transmit the first association request/response frame may be named a non-transmission link (nt_link).

After receiving the status code, the receiving MLD may operate as follows. The receiving MLD may send a second association request frame to the transmitting MLD over the second link based on the status code. The receiving MLD may receive a second association response frame from the transmitting MLD over the second link. The receiving MLD may perform ML setup with the transmitting MLD based on the second link. That is, the receiving MLD may directly perform ML setup through the second link indicating that the status code is licensed.

That is, the present embodiment proposes the following method: by inserting a specific status code during the multilink establishment, information indicating that the multilink establishment has failed is transmitted without allowing transmission of the link, regardless of whether the non-transmission link is allowed.

Advantageous effects

According to the embodiments presented in this specification, upon receiving a specific status code, the non-AP MLD may transmit an association request frame over the non-transmission link indicated by the specific status code the next time a multilink establishment is requested. For example, the receiving MLD may receive the status code and confirm that the second link is an allowed link, and there is an effect that the second receiving STA may directly attempt multi-link establishment to the second transmitting STA through the second link without having to transmit the association request frame through the first link. Thus, there is an effect that the multilink configuration can be efficiently improved by the status code without additional overhead.

Drawings

Fig. 1 shows an example of a transmitting device and/or a receiving device of the present specification.

Fig. 2 is a conceptual diagram illustrating a structure of a Wireless Local Area Network (WLAN).

Fig. 3 illustrates a general link establishment procedure.

Fig. 4 illustrates an example of a PPDU used in the IEEE standard.

Fig. 5 illustrates UL-MU based operation.

Fig. 6 illustrates an example of a trigger frame.

Fig. 7 illustrates an example of a common information field of a trigger frame.

Fig. 8 illustrates an example of subfields included in the per-user information field.

Fig. 9 depicts the technical features of the UORA scheme.

Fig. 10 illustrates an example of a PPDU used in the present specification.

Fig. 11 illustrates an example of a transmitting apparatus and/or a receiving apparatus of the modification of the present specification.

Fig. 12 shows an example of the structure of the STA MLD.

Fig. 13 shows an example of basic multilink establishment.

Fig. 14 shows the structure of the multilink control field and the common information field of the multilink element.

Fig. 15 shows a structure of a link information field of a multilink element.

Fig. 16 shows an example of multilink establishment in the case of embodiment 1-1).

Fig. 17 shows an example of multilink establishment in the case of embodiment 1-2).

Fig. 18 shows an example of multilink establishment in the case of embodiment 2-1).

Fig. 19 shows an example of multilink establishment in the case of embodiment 3).

Fig. 20 shows an example of multilink establishment in the case of embodiment 4).

Fig. 21 is a flowchart illustrating a procedure in which a transmitting MLD informs whether to establish a plurality of links based on a status code according to the present embodiment.

Fig. 22 is a flowchart illustrating a procedure of whether or not the receiving MLD establishes a plurality of links based on status code reception according to the present embodiment.

Detailed Description

In this specification, "a or B" may mean "a only", "B only" or "both a and B". In other words, in the present specification, "a or B" may be interpreted as "a and/or B". For example, in this specification, "A, B or C" may mean any combination of "a only", "B only", "C only" or "A, B, C".

Slash (/) or comma as used in this specification may mean "and/or". For example, "A/B" may mean "A and/or B". Thus, "a/B" may mean "a only", "B only" or "both a and B". For example, "A, B, C" may mean "A, B or C".

In the present specification, "at least one of a and B" may mean "a only", "B only", 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".

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

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

The technical features described separately in one drawing of the present specification may be implemented separately or may be implemented simultaneously.

The following examples of the present specification may be applied to various wireless communication systems. For example, the following examples of the present specification may be applied to a Wireless Local Area Network (WLAN) system. For example, the present description may be applied to the IEEE 802.11a/g/n/ac standard or the IEEE 802.11ax standard. In addition, the present specification can also be applied to the newly proposed EHT standard or IEEE 802.11be standard. Furthermore, the examples of the present specification can also be applied to a new WLAN standard enhanced from the EHT standard or the IEEE 802.11be standard. In addition, examples of the present specification may be applied to a mobile communication system. For example, it may be applied to a mobile communication system based on Long Term Evolution (LTE) depending on 3 rd generation partnership project (3 GPP) standards and LTE-based evolution. In addition, examples of the present specification may be applied to a communication system of a 5G NR standard based on a 3GPP standard.

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

In the example of fig. 1, various technical features described below may be performed. Fig. 1 relates to at least one Station (STA). For example, STAs 110 and 120 of the present description 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. STAs 110 and 120 of the present description may also be referred to as various terms such as networks, base stations, node bs, access Points (APs), repeaters, routers, repeaters, and the like. STAs 110 and 120 of the present specification may also be referred to as various names such as a receiving device, a transmitting device, a receiving STA, a transmitting STA, a receiving apparatus, a transmitting apparatus, etc.

For example, STAs 110 and 120 may function as APs or non-APs. That is, STAs 110 and 120 of the present description may function as an AP and/or a non-AP.

In addition to the IEEE 802.11 standard, STAs 110 and 120 of the present specification may together support various communication standards. For example, communication standards based on 3GPP standards (e.g., LTE-A, 5G NR standards) and the like may be supported. In addition, the STA of the present description may be implemented as various devices such as a mobile phone, a vehicle, a personal computer, and the like. In addition, the STA of the present specification may support communication for various communication services such as voice call, video call, data communication, and self-driving (autonomous driving).

STAs 110 and 120 of the present description may include a Medium Access Control (MAC) compliant with the IEEE 802.11 standard and a physical layer interface for a radio medium.

STAs 110 and 120 will be described below with reference to sub-picture (a) of fig. 1.

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

The transceiver 113 of the first STA performs a signal transmission/reception operation. Specifically, IEEE 802.11 packets (e.g., IEEE 802.11a/b/g/n/ac/ax/be, etc.) may be transmitted/received.

For example, the first STA 110 may perform operations expected by the AP. For example, the processor 111 of the AP may receive signals through the transceiver 113, process Received (RX) signals, generate Transmit (TX) signals, and provide control over signal transmission. The memory 112 of the AP may store signals (e.g., RX signals) received through the transceiver 113 and may store signals (e.g., TX signals) to be transmitted through the transceiver.

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

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

For example, the operations of the apparatus indicated as an AP in the description 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 an AP may be controlled by the processor 111 of the first STA 110, and the related signals 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 TX/RX signals 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 related 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 TX/RX signals of the AP may be stored in the memory 122 of the second STA 120.

For example, in the description described below, the operation of a 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 STA120 is non-AP, the operation of the device indicated as non-AP may be controlled by the processor 121 of the second STA120, and the related 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 non-AP, the operation of the device indicated as non-AP may be controlled by the processor 111 of the first STA 110, and the related signals 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 operation of the non-AP or TX/RX signals of the non-AP may be stored in the memory 112 of the first STA 110.

In the description described below, devices called (transmitting/receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting/receiving) terminal, (transmitting/receiving) device, (transmitting/receiving) apparatus, network, and the like may refer to STAs 110 and 120 of fig. 1 in an implied manner. For example, devices indicated (but not specifically numbered) (transmitting/receiving) STA, first STA, second STA, STA1, STA2, AP, first AP, second AP, AP1, AP2, (transmitting/receiving) terminal, (transmitting/receiving) device, (transmitting/receiving) apparatus, network, etc. may implicitly refer to STA 110 and 120 of fig. 1. For example, in the following examples, operations of various STAs transmitting/receiving signals (e.g., PPDUs) may be performed in the transceivers 113 and 123 of fig. 1. In addition, in the following examples, operations of various STAs generating TX/RX signals or performing data processing and calculation in advance for the TX/RX signals may be performed in the processors 111 and 121 of fig. 1. Examples of operations for generating TX/RX signals or performing data processing and computation in advance may include, for example: 1) Operations of determining/obtaining/configuring/calculating/decoding/encoding bit information of subfields (SIG, STF, LTF, data) included in the PPDU; 2) An operation of determining/configuring/obtaining time resources or frequency resources (e.g., subcarrier resources) for subfields (SIG, STF, LTF, data) included in the PPDU, etc.; 3) An operation of determining/configuring/obtaining a specific sequence (e.g., pilot sequence, STF/LTF sequence, additional sequence applied to SIG) for a subfield (SIG, STF, LTF, data) field included in the PPDU, etc.; 4) Power control operation and/or power save operation applied to the STA; and 5) operations related to determination/acquisition/configuration/decoding/encoding of an ACK signal, and the like. 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 TX/RX signals may be stored in the memories 112 and 122 of fig. 1.

The foregoing apparatus/STA of sub-graph (a) of fig. 1 may be modified as shown in sub-graph (b) of fig. 1. Hereinafter, STA 110 and STA120 of the present specification will be described based on sub-diagram (b) of fig. 1.

For example, transceivers 113 and 123 shown in sub-graph (b) of fig. 1 may perform the same functions as the aforementioned transceivers shown in sub-graph (a) of fig. 1. For example, the processing chips 114 and 124 shown in sub-graph (b) of fig. 1 may include processors 111 and 121 and memories 112 and 122. The processors 111 and 121 and memories 112 and 122 shown in sub-graph (b) of fig. 1 may perform the same functions as the aforementioned processors 111 and 121 and memories 112 and 122 shown in sub-graph (a) of fig. 1.

A mobile terminal, a wireless device, a wireless transmit/receive unit (WTRU), a User Equipment (UE), a Mobile Station (MS), a mobile subscriber unit, a user STA, a network, a base station, a node B, an Access Point (AP), a repeater, a router, a repeater, a receive unit, a transmit unit, a receive STA, a transmit STA, a receive device, a transmit device, a receive apparatus, and/or a transmit apparatus described below may mean STAs 110 and 120 shown in sub-graph (a)/(B) of fig. 1, or may mean processing chips 114 and 124 shown in sub-graph (B) of fig. 1. That is, technical features of the present specification may be performed in STAs 110 and 120 shown in sub-graph (a)/(b) of fig. 1, or transceivers 113 and 123 shown in sub-graph (a)/(b) of fig. 1 may be performed only in processing chips 114 and 124 shown in sub-graph (b) of fig. 1. For example, the technical feature of the transmitting STA transmitting the control signal may be understood as the technical feature of transmitting the control signal generated in the processors 111 and 121 illustrated in the sub-diagram (a)/(b) of fig. 1 through the transceiver 113 illustrated in the sub-diagram (a)/(b) of fig. 1. Alternatively, the technical feature of the transmitting STA transmitting the control signal may be understood as the technical feature of generating the control signal to be transmitted to the transceivers 113 and 123 in the processing chips 114 and 124 shown in the sub-graph (b) of fig. 1.

For example, the technical feature of the receiving STA receiving the control signal may be understood as the technical feature of receiving the control signal through the transceivers 113 and 123 shown in the sub-graph (a) of fig. 1. Alternatively, the technical features of the receiving STA to receive the control signal may be understood as the technical features of obtaining the control signal received in the transceivers 113 and 123 shown in the sub-graph (a) of fig. 1 through the processors 111 and 121 shown in the sub-graph (a) of fig. 1. Alternatively, the technical features of the receiving STA to receive the control signal may be understood as the technical features of the receiving STA to obtain the control signals received in the transceivers 113 and 123 shown in the sub-graph (b) of fig. 1 through the processing chips 114 and 124 shown in the sub-graph (b) of fig. 1.

Referring to sub-graph (b) of fig. 1, software codes 115 and 125 may be included in memories 112 and 122. The software codes 115 and 125 may include instructions for controlling the operation of the processors 111 and 121. Software codes 115 and 125 may be included as various programming languages.

The processors 111 and 121 or the processing chips 114 and 124 of fig. 1 may include Application Specific Integrated Circuits (ASICs), other chipsets, logic circuits, and/or data processing devices. The processor may be an Application Processor (AP). For example, processors 111 and 121 or processing chips 114 and 124 of FIG. 1 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). For example, processors 111 and 121 or processing chips 114 and 124 of FIG. 1 may be implemented byManufactured snapdagantm processor family, consisting ofEXYNOSTM processor series manufactured by +.>Processor series manufactured by ∈>HELIOTM processor series manufactured by +.>The ATOMTM processor family is manufactured or processors enhanced from these processors.

In the present specification, the uplink may mean a link for communication from a non-AP STA to an SP STA, and an uplink PPDU/packet/signal or the like may be transmitted through the uplink. In addition, in the present specification, the downlink may mean a link for communication from an AP STA to a non-AP STA, and a downlink PPDU/packet/signal or the like may be transmitted through the downlink.

The upper part of fig. 2 illustrates the structure of an infrastructure Basic Service Set (BSS) of Institute of Electrical and Electronics Engineers (IEEE) 802.11.

Referring to the upper part of fig. 2, the wireless LAN system may include one or more infrastructure BSSs 200 and 205 (hereinafter, referred to as BSSs). BSSs 200 and 205, which are sets of an AP and an STA (e.g., an Access Point (AP) 225 and a station (STA 1) 200-1) that are successfully synchronized to communicate with each other, are not concepts indicating a specific area. BSS205 may include one or more STAs 205-1 and 205-2 that may join an AP 230.

The BSS may include at least one STA, an AP providing a distributed service, and a Distributed System (DS) 210 connecting the plurality of APs.

The distributed system 210 may implement an Extended Service Set (ESS) 240 extended by connecting the plurality of BSSs 200 and 205. ESS240 may be used as a term indicating a network configured by connecting one or more APs 225 or 230 via distributed system 210. The APs included in one ESS240 may have the same Service Set Identification (SSID).

Portal 220 may serve as a bridge connecting a wireless LAN network (IEEE 802.11) and another network (e.g., 802. X).

In the BSS shown in the upper part of fig. 2, a network between the APs 225 and 230 and the STAs 200-1, 205-1, and 205-2 may be implemented. However, the network is configured to perform communication between STAs even without the APs 225 and 230. A network that performs communication by configuring a network between STAs even without the APs 225 and 230 is defined as an ad hoc network or an Independent Basic Service Set (IBSS).

The lower part of fig. 2 illustrates a conceptual diagram illustrating an IBSS.

Referring to the lower part of fig. 2, the IBSS is a BSS operating in an ad hoc mode. Since the IBSS does not include an Access Point (AP), a centralized management entity performing management functions at the center does not exist. That is, in an IBSS, the STAs 250-1, 250-2, 250-3, 255-4, and 255-5 are managed in a distributed manner. In an IBSS, all STAs 250-1, 250-2, 250-3, 255-4, and 255-5 may be comprised of removable STAs and are not allowed to access the DS to form a self-contained network.

Fig. 3 illustrates a general link establishment procedure.

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 the participating network. The STA needs to identify a compatible network before joining a wireless network, and the process of identifying networks existing in a specific area is called scanning. The scanning method comprises active scanning and passive scanning.

Fig. 3 illustrates a network discovery operation including an active scanning procedure. In the active scanning, the STA performing the scanning transmits a probe request frame and waits for a response to the probe request frame in order to identify which AP exists around while moving to a channel. The responder transmits a probe response frame to the STA that has transmitted the probe request frame as a response to the probe request frame. Here, the responder may be an STA transmitting the last beacon frame in the BSS of the channel being scanned. In the BSS, the AP is a responder since the AP transmits a beacon frame. In IBSS, the responders are not stationary because STAs in the IBSS send beacon frames in turn. For example, when the STA transmits a probe request frame via channel 1 and receives a probe response frame via channel 1, the STA may store 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., transmit a probe request and receive a probe response via channel 2).

Although not shown in fig. 3, scanning may be performed by a passive scanning method. In passive scanning, a STA performing scanning may wait for a beacon frame while moving to a channel. The beacon frame is one of management frames in IEEE 802.11, and is periodically transmitted to indicate the presence of a wireless network and enable STAs performing scanning to find and join the wireless network. In a BSS, an AP is configured to periodically transmit a beacon frame. In an IBSS, STAs in the IBSS transmit beacon frames in turn. Upon receiving the beacon frame, the STA performing scanning stores information about BSSs included in the beacon frame and records beacon frame information in respective channels while moving to another channel. The STA that receives the beacon frame may store BSS-related information included in the received beacon frame, may move to the next channel, and may perform scanning in the next channel by the same method.

After discovering the network, the STA may perform an authentication procedure in S320. This authentication process may be referred to as a first authentication process to be clearly distinguished from the security setup operation in S340 that follows. The authentication procedure in S320 may include a procedure in which the STA transmits an authentication request frame to the AP and the AP transmits an authentication response frame to the STA in response. The authentication frame for authentication request/response is a management frame.

The authentication frame may include information about an authentication algorithm number, an authentication transaction sequence number, a status code, challenge text, a Robust Secure Network (RSN), and a limited loop group.

The STA may transmit 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 authentication processing result to the STA via an authentication response frame.

When the STA is successfully authenticated, the STA may perform an association procedure in S330. The association procedure includes a procedure in which the STA transmits an association request frame to the AP and the AP transmits an association response frame to the STA in response. For example, the association request frame may include information about various capabilities, beacon listening intervals, service Set Identifiers (SSID), supported rates, supported channels, RSNs, mobile domains, supported operation categories, traffic Indication Map (TIM) broadcast requests, and interworking service capabilities. For example, the association response frame may include information about various capabilities, status codes, association IDs (AID), supported rates, enhanced Distributed Channel Access (EDCA) parameter sets, received Channel Power Indicator (RCPI), received signal-to-noise indicator (RSNI), mobility domain, time out interval (association recovery time), overlapping BSS scan parameters, TIM broadcast response, and QoS map.

In S340, the STA may perform a security setup procedure. The security establishment procedure in S340 may include a procedure of establishing a private key through a four-way handshake (e.g., through an Extensible Authentication Protocol (EAPOL) frame via a LAN).

Fig. 4 illustrates an example of a PPDU used in the IEEE standard.

As shown, various types of PHY Protocol Data Units (PPDUs) are used in the IEEE a/g/n/ac standard. Ext> specificallyext>,ext> theext> LTFext> andext> theext> STFext> includeext> trainingext> signalsext>,ext> SIGext> -ext> aext> andext> SIGext> -ext> bext> includeext> controlext> informationext> forext> aext> receivingext> staext>,ext> andext> aext> dataext> fieldext> includesext> userext> dataext> correspondingext> toext> aext> psduext> (ext> macext> pduext> /ext> aggregateext> macext> pduext>)ext>.ext>

Fig. 4 also includes an example of a HE PPDU according to IEEE 802.11 ax. The HE PPDU according to fig. 4 is an exemplary PPDU for a plurality of users. HE-SIG-B may be included only in PPDUs for multiple users, and HE-SIG-B may be omitted in PPDUs for a single user.

As illustrated in fig. 4, the HE-PPDU for a plurality of users (MUs) 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. The various fields may be transmitted within the time period shown (i.e., 4 or 8 mus).

Hereinafter, a Resource Unit (RU) for PPDU is described. An RU may include a plurality of subcarriers (or tones). The RU may be used to transmit signals to a plurality of STAs according to OFDMA. In addition, an RU may also be defined to transmit a signal to one STA. RU may be used for STF, LTF, data fields, etc.

RU described in this specification can be used for Uplink (UL) communication and Downlink (DL) communication. For example, when performing UL-MU communication solicited by a trigger frame, a transmitting STA (e.g., an 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 through the trigger frame. Thereafter, the first STA may transmit a first trigger-based PPDU based on the first RU, and the second STA may transmit a second trigger-based PPDU based on the second RU. The first/second trigger-based PPDUs are transmitted to the AP in the same (or overlapping) time periods.

For example, when configuring a DL MU PPDU, a transmitting STA (e.g., an 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, a transmitting STA (e.g., AP) may transmit the HE-STF, HE-LTF, and data field for the first STA through a first RU in one MU PPDU and may transmit the HE-STF, HE-LTF, and data field for the second STA through a second RU.

Fig. 5 illustrates UL-MU based operation. As illustrated, a transmitting STA (e.g., AP) may perform channel access through contention (e.g., 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 a PPDU including a trigger frame, a Trigger (TB) -based PPDU is transmitted after a delay corresponding to a SIFS.

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

Specific features of the trigger frame are described with reference to fig. 6 to 8. Even if UL-MU communication is used, an Orthogonal Frequency Division Multiple Access (OFDMA) scheme or a MU-MIMO scheme may be used, and both the OFDMA and MU-MIMO schemes may be used.

Fig. 6 illustrates an example of a trigger frame. The trigger frame of fig. 6 allocates resources for uplink multi-user (MU) transmissions and may be transmitted, for example, from an AP. The trigger frame may be composed of a MAC frame and may be included in the PPDU.

Each field shown in fig. 6 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 drawings.

The frame control field 1110 of fig. 6 may include information related to a MAC protocol version and additional control information. The duration field 1120 may include time information of NAV configuration or information related to an identifier (e.g., AID) of the STA.

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 a STA (e.g., AP) transmitting the corresponding trigger frame. The common information field 1150 includes common control information applied to the receiving STAs receiving the corresponding trigger frame. Ext>ext> forext>ext> exampleext>ext>,ext>ext> aext>ext> fieldext>ext> indicatingext>ext> aext>ext> lengthext>ext> ofext>ext> anext>ext> Lext>ext> -ext>ext> SIGext>ext> fieldext>ext> ofext>ext> anext>ext> uplinkext>ext> PPDUext>ext> transmittedext>ext> inext>ext> responseext>ext> toext>ext> aext>ext> correspondingext>ext> triggerext>ext> frameext>ext> orext>ext> informationext>ext> forext>ext> controllingext>ext> contentsext>ext> ofext>ext> aext>ext> SIGext>ext> -ext>ext> aext>ext> fieldext>ext> (ext>ext> i.e.ext>ext>,ext>ext> heext>ext> -ext>ext> SIGext>ext> -ext>ext> aext>ext> fieldext>ext>)ext>ext> ofext>ext> theext>ext> uplinkext>ext> PPDUext>ext> transmittedext>ext> inext>ext> responseext>ext> toext>ext> theext>ext> correspondingext>ext> triggerext>ext> frameext>ext> mayext>ext> beext>ext> includedext>ext>.ext>ext> In addition, as the common control information, information related to the length of the CP of the uplink PPDU transmitted in response to the corresponding trigger frame or information related to the length of the LTF field may be included.

In addition, it is preferable to include per-user information fields 1160#1 to 1160#n corresponding to the number of receiving STAs receiving the trigger frame of fig. 6. The per-user information field may also be referred to as an "allocation field".

In addition, the trigger frame of fig. 6 may include a padding field 1170 and a frame check sequence field 1180.

Each of the per-user information fields 1160#1 through 1160#n shown in fig. 6 may include a plurality of subfields.

Fig. 7 illustrates an example of a common information field of a trigger frame. The subfields of fig. 7 may be partially omitted and additional subfields may be added. In addition, the length of each of the subfields illustrated may be changed.

The illustrated length field 1210 has the same value as a length field of an L-SIG field of an uplink PPDU transmitted in response to a 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 may be used to indicate the length of the corresponding uplink PPDU.

In addition, the cascade identifier field 1220 indicates whether a cascade operation is performed. Tandem operation means that within the same TXOP, downlink MU transmissions and uplink MU transmissions are performed together. That is, this means that downlink MU transmission is performed, and thereafter, uplink MU transmission is performed after a preset time (e.g., SIFS). During the tandem operation, only one transmitting device (e.g., an AP) may perform downlink communication, and a plurality of transmitting devices (e.g., non-APs) may perform uplink communication.

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

Ext>ext>ext> theext>ext>ext> HEext>ext>ext> -ext>ext>ext> SIGext>ext>ext> -ext>ext>ext> aext>ext>ext> informationext>ext>ext> fieldext>ext>ext> 1240ext>ext>ext> mayext>ext>ext> includeext>ext>ext> informationext>ext>ext> thatext>ext>ext> controlsext>ext>ext> theext>ext>ext> contentext>ext>ext> ofext>ext>ext> aext>ext>ext> SIGext>ext>ext> -ext>ext>ext> aext>ext>ext> fieldext>ext>ext> (ext>ext>ext> i.e.ext>ext>ext>,ext>ext>ext> HEext>ext>ext> -ext>ext>ext> SIGext>ext>ext> -ext>ext>ext> aext>ext>ext> fieldext>ext>ext>)ext>ext>ext> ofext>ext>ext> theext>ext>ext> uplinkext>ext>ext> ppduext>ext>ext> inext>ext>ext> responseext>ext>ext> toext>ext>ext> theext>ext>ext> correspondingext>ext>ext> triggerext>ext>ext> frameext>ext>ext>.ext>ext>ext>

The CP and LTF type field 1250 may include information related to the CP length and LTF length of the uplink PPDU transmitted in response to the corresponding trigger frame. The trigger type field 1260 may indicate the purpose of using the corresponding trigger frame, e.g., a typical trigger, a trigger for beamforming, a request for a block ACK/NACK, etc.

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

Fig. 8 illustrates an example of subfields included in the per-user information field. The user information field 1300 of fig. 8 may be understood as any of the per-user information fields 1160#1 to 1160#n mentioned above with reference to fig. 6. The subfields included in the user information field 1300 of fig. 8 may be partially omitted and additional subfields may be added. In addition, the length of each of the subfields illustrated may be changed.

The user identifier field 1310 of fig. 8 indicates an identifier of a STA (i.e., a receiving STA) corresponding to per-user information. Examples of the identifier may be all or part of an Association Identifier (AID) value of the receiving STA.

In addition, an RU allocation field 1320 may be included. That is, when the receiving STA identified through the user identifier field 1310 transmits a TB PPDU in response to a trigger frame, the TB PPDU is transmitted through the RU indicated by the RU allocation field 1320.

The subfields of fig. 8 may include a coding type field 1330. The coding type field 1330 may indicate a 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".

In addition, the subfields of fig. 8 may include an MCS field 1340. The MCS field 1340 may indicate an MCS scheme applied to 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".

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

Fig. 9 depicts the technical features of the UORA scheme.

A transmitting STA (e.g., AP) may allocate six RU resources by triggering a frame as shown in fig. 9. Specifically, the AP may allocate first RU resources (AID 0, RU 1), second RU resources (AID 0, RU 2), third RU resources (AID 0, RU 3), fourth RU resources (AID 2045, RU 4), fifth RU resources (AID 2045, RU 5), and sixth RU resources (AID 3, RU 6). Information related to AID 0, AID 3, or AID 2045 may be included, for example, in the user identifier field 1310 of fig. 8. Information related to RU 1 through RU 6 may be included, for example, in RU allocation field 1320 of fig. 8. Aid=0 may mean UORA resources for associated STAs and aid=2045 may mean UORA resources for non-associated STAs. Accordingly, the first to third RU resources of fig. 9 may be used as UORA resources for associated STAs, the fourth and fifth RU resources of fig. 9 may be used as UORA resources for non-associated STAs, and the sixth RU resource of fig. 9 may be used as typical resources for UL MUs.

In the example of fig. 9, the OFDMA random access backoff (OBO) of STA1 is reduced to 0, and STA1 randomly selects the second RU resources (AID 0, RU 2). In addition, since the OBO counter of STA2/3 is greater than 0, no uplink resources are allocated to STA2/3. In addition, regarding STA4 in fig. 9, since the AID (e.g., aid=3) of STA4 is included in the trigger frame, the resources of RU 6 are allocated without backoff.

Specifically, since STA1 of fig. 9 is an associated STA, the total number of eligible RA RUs for STA1 is 3 (RU 1, RU 2, and RU 3), and thus STA1 decrements the OBO counter by 3 such that the OBO counter becomes 0. In addition, since STA2 of fig. 9 is an associated STA, 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, since STA3 of fig. 9 is a non-associated STA, 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.

Hereinafter, PPDUs transmitted/received in STAs of the present specification will be described.

Fig. 10 illustrates an example of a PPDU used in the present specification.

The PPDU of fig. 10 may be named in various terms such as EHT PPDU, TX PPDU, RX PPDU, first type or nth type PPDU, etc. For example, in the present specification, a PPDU or an EHT PPDU may be named in various terms such as TX PPDU, RX PPDU, first type or nth type PPDU, etc. In addition, the EHT PPDU may be used in an EHT system and/or a new WLAN system enhanced with respect to the EHT system.

The PPDU of fig. 10 may indicate all or a portion of the type of PPDU used in the EHT system. For example, the example of fig. 10 may be used for both Single User (SU) and multi-user (MU) modes. In other words, the PPDU of fig. 10 may be a PPDU for one receiving STA or a plurality of receiving STAs. When the PPDU of fig. 10 is used in a Trigger (TB) -based mode, the EHT-SIG of fig. 10 may be omitted. In other words, an STA that has received a trigger frame for an uplink MU (UL-MU) may transmit a PPDU in which the EHT-SIG is omitted in the example of fig. 10.

In fig. 10, L-STF to EHT-LTF may be referred to as a preamble or a physical preamble, and may be generated/transmitted/received/obtained/decoded in a physical layer.

The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and EHT-SIG fields of FIG. 10 may be determined to be 312.5kHz and the subcarrier spacing of the EHT-STF, EHT-LTF, and data fields may be determined to be 78.125kHz. That is, the tone indexes (or subcarrier indexes) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and EHT-SIG fields may be expressed in units of 312.5kHz, and the tone indexes (or subcarrier indexes) of the EHT-STF, EHT-LTF, and data fields may be expressed in units of 78.125kHz.

In the PPDU of fig. 10, L-LTE and L-STF may be the same as those in the conventional field.

The L-SIG field of fig. 10 may include bit information of, for example, 24 bits. For example, the 24-bit information may include a rate field of 4 bits, a reserved bit of 1 bit, a length field of 12 bits, a parity bit of 1 bit, and a tail bit of 6 bits. For example, a 12-bit length field may include information related to the length or duration of the PPDU. For example, a 12-bit length field may be determined based on the type of PPDU. For example, when the PPDU is a non-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 a HE PPDU, the value of the length field may be determined as "multiple of 3" +1 or "multiple of 3" +2. In other words, for a non-HT, VHT PPDU or EHT PPDU, the value of the length field may be determined as a multiple of 3, and for an HE PPDU, the value of the length field may be determined as a "multiple of 3" +1 or a "multiple of 3" +2.

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

The transmitting STA may generate a RL-SIG generated in the same manner as the L-SIG. BPSK modulation may be applied to the RL-SIG. The receiving STA may learn that the RX PPDU is a HE PPDU or an EHT PPDU based on the existence of the RL-SIG.

The common SIG (U-SIG) may be inserted after the RL-SIG of fig. 10. The U-SIB may be named in various terms such as a first SIG field, a first SIG, a first type SIG, a control signal field, a first (type) control signal, etc.

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 OFDM symbols in succession). Each symbol of the U-SIG (e.g., an OFDM symbol) may have a duration of 4 μs. Each symbol of the U-SIG may be used to transmit 26 bits of information. For example, each symbol of the U-SIG may be transmitted/received based on 52 data tones and 4 pilot tones.

With the U-SIG (or U-SIG field), for example, a-bit information (e.g., 52 uncoded bits) may be transmitted. The first symbol of the U-SIG may transmit the first X bits of information (e.g., 26 uncoded bits) of the A bits of information, and the second symbol of the U-SIB may transmit the remaining Y bits of information (e.g., 26 uncoded bits) of the A bits of information. For example, the transmitting STA may obtain 26 uncoded bits included in each U-SIG symbol. The transmitting STA may perform convolutional encoding (i.e., BCC encoding) based on a rate of r=1/2 to generate 52 encoded bits, and may perform interleaving on the 52 encoded 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. One U-SIG symbol may be transmitted based on 65 tones (subcarriers) from subcarrier index-28 to subcarrier index +28, except for DC index 0. The 52 BPSK symbols generated by the transmitting STA may be transmitted based on the remaining tones (subcarriers) except for pilot tones (i.e., tones-21, -7, +7, +21).

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 of length 4 bits) and a tail field (e.g., a field of length 6 bits). The CRC field and the tail field may be transmitted over a second symbol of the U-SIG. The CRC field may be generated based on 26 bits allocated to the first symbol of the U-SIG and the remaining 16 bits in the second symbol except for 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 trellis of the convolutional decoder and may be set to, for example, "000000".

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

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

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

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

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

For example, the U-SIG may comprise: 1) A bandwidth field including information related to a bandwidth; 2) A field including information related to an MCS scheme applied to the EHT-SIG; 3) An indication field including information on whether to apply a dual subcarrier modulation (DCM) scheme to the EHT-SIG; 4) A field including information related to a number of symbols for the EHT-SIG; 5) A field including information regarding whether to generate an EHT-SIG across a full frequency band; 6) A field including information related to a type of EHT-LTF/STF; and 7) information related to fields indicating the EHT-LTF length and the CP length.

In the following example, signals expressed 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 signals transmitted/received based on the PPDU of fig. 10. The PPDU of fig. 10 may be used to transmit/receive various types of frames. For example, the PPDU of fig. 10 may be used for the control frame. Examples of control frames may include Request To Send (RTS), clear To Send (CTS), power save polling (PS poll), blockACKReq, blockAck, null Data Packet (NDP) advertisement, and trigger frames. For example, the PPDU of fig. 10 may be used for management frames. Examples of the management frame may include a beacon frame, (re) association request frame, (re) association response frame, probe request frame, and probe response frame. For example, the PPDU of fig. 10 may be used for a data frame. For example, the PPDU of fig. 10 may be used to simultaneously transmit at least two or more of a control frame, a management frame, and a data frame.

Fig. 11 illustrates an example of a modified transmitting apparatus and/or receiving apparatus of the present specification.

Each device/STA of sub-graph (a)/(b) of fig. 1 may be modified as shown in fig. 11. Transceiver 630 of fig. 11 may be identical to transceivers 113 and 123 of fig. 1. The transceiver 630 of fig. 11 may include a receiver and a transmitter.

Processor 610 of fig. 11 may be identical to processors 111 and 121 of fig. 1. Alternatively, the processor 610 of FIG. 11 may be identical to the processing chips 114 and 124 of FIG. 1.

Memory 620 of fig. 11 may be identical to memories 112 and 122 of fig. 1. Alternatively, memory 620 of FIG. 11 may be a separate external memory from memories 112 and 122 of FIG. 1.

Referring to fig. 11, a power management module 611 manages power for the processor 610 and/or the transceiver 630. The battery 612 supplies power to the power management module 611. The display 613 outputs the result processed by the processor 610. The keyboard 614 receives input to be used by the processor 610. A keyboard 614 may be displayed on the display 613. The SIM card 615 may be an integrated circuit for securely storing an International Mobile Subscriber Identity (IMSI) and its associated keys for identifying and authenticating subscribers on mobile telephone devices such as mobile telephones and computers.

Referring to fig. 11, a speaker 640 may output results related to sound processed by the processor 610. The microphone 641 may receive input related to sound to be used by the processor 610.

Hereinafter, technical features of a multi-link (ML) supported by the STA of the present specification will be described.

STAs (AP and/or non-AP STAs) of the present description may support multi-link (ML) communications. ML communication may mean communication that supports multiple links. Links associated with ML communications may include channels in the 2.4GHz band, the 5GHz band, and the 6GHz band (e.g., 20/40/80/160/240/320MHz channels).

Multiple links for ML communications may be established in various ways. For example, the plurality of links for ML communication supported by one STA may be a plurality of channels in the 2.4GHz band, a plurality of channels in the 5GHz band, and a plurality of channels in the 6GHz band. Alternatively, the plurality of links may be a combination of at least one channel within the 2.4GHz band (or the 5GHz/6GHz band) and at least one channel within the 5GHz band (or the 2.4GHz/6GHz band). Further, at least one of the plurality of links for ML communication supported by one STA may be a channel to which preamble puncturing is applied.

The STA may perform ML setup to perform ML communication. ML setup may be performed based on management frames or control frames such as beacons, probe requests/responses, and association requests/responses. For example, information about ML setup may be included in element fields included in beacons, probe requests/responses, and association requests/responses.

When ML setup is complete, an enable link for ML communication may be determined. The STA may perform frame exchange over at least one of the plurality of links determined to be enabled links. For example, the enable link may be used for at least one of a management frame, a control frame, and a data frame.

When one STA supports a plurality of links, a transmitting/receiving device supporting each link may operate like one logical STA. For example, one STA supporting two links may be represented as one ML device (multi-link device; MLD) including a first STA for a first link and a second STA for a second link. For example, one AP supporting two links may be represented as one AP MLD including a first AP for a first link and a second AP for a second link. In addition, one non-AP supporting two links may be expressed as one non-AP MLD including a first STA for a first link and a second STA for a second link.

More specific features of ML build are described below.

The MLD (AP MLD and/or non-AP MLD) may transmit information on links that the corresponding MLD can support through ML setup. The link-related information may be configured in various ways. For example, the link-related information includes at least one of 1) information on whether MLD (or STA) supports simultaneous RX/TX operation, 2) information on the number/upper limit of uplink/downlink links supported by MLD (or STA), 3) information on location/frequency band/resource of uplink/downlink links supported by MLD (or STA), 4) types (management, control, data, etc.) of frames available or preferred in at least one uplink/downlink link, 5) ACK policy information available or preferred in respect of at least one uplink/downlink link, 6) information on TID (traffic identifier) available or preferred in respect of at least one uplink/downlink link. The TID is related to the priority of traffic data and is represented by 8 types of values according to the conventional wireless LAN standard. That is, 8 TID values corresponding to 4 Access Categories (AC) (ac_bk (background), ac_be (best effort), ac_vi (video), ac_vo (voice)) according to the conventional wireless LAN standard may BE defined.

For example, all TIDs for uplink/downlink mapping may be set in advance. In particular, if negotiation is not completed through ML setup, all TIDs may be used for ML communication, and if mapping between negotiated uplink/downlink and TIDs is established through additional ML setup, the negotiated TIDs may be used for ML communication.

Multiple links that may be used by a transmitting MLD and a receiving MLD in connection with ML communications may be set by ML setup, and this may be referred to as an enabled link. The enable links may be named differently in various ways. For example, it may be named as various expressions such as a first link, a second link, a transmission link, and a reception link.

After the ML setup is complete, the MLD may update the ML setup. For example, when information about a link needs to be updated, the MLD may send information about a new link. Information about the new link may be transmitted based on at least one of the management frame, the control frame, and the data frame.

The apparatus described below may be the device of fig. 1 and/or 11, and the PPDU may be the PPDU of fig. 10. The device may be an AP or a non-AP STA. The devices described below may be AP multilink devices (MLDs) or non-AP STA MLDs supporting multiple links.

In EHT (extremely high throughput) (standard discussed after 802.11 ax), a multilink environment in which one or more frequency bands are simultaneously used is considered. When the device supports multiple links, the device may use one or more frequency bands (e.g., 2.4GHz, 5GHz, 6GHz, 60GHz, etc.) simultaneously or alternately.

In the following description, MLD means a multi-link device. The MLD has one or more STAs connected and has a MAC Service Access Point (SAP) that communicates with an uplink layer (logical link control, LLC). MLD may mean a physical device or a logical device. Hereinafter, the device may mean MLD.

In the following description, a transmitting apparatus and a receiving apparatus may mean MLD. The first link of the reception/transmission apparatus may be a terminal (e.g., STA or AP) that is included in the reception/transmission apparatus and performs signal transmission/reception through the first link. The second link of the reception/transmission apparatus may be a terminal (e.g., STA or AP) that transmits/receives a signal through the second link included in the reception/transmission apparatus.

In ieee802.11be, two types of multi-link operation may be supported. For example, simultaneous Transmit and Receive (STR) and non-STR operations may be considered. For example, STRs may be referred to as asynchronous multilink operation, and non-STRs may be referred to as synchronous multilink operation. The multilink may comprise multiple frequency bands. That is, the multilink may mean a link included in several frequency bands, or may mean a plurality of links included in one frequency band.

EHT (11 be) considers a multilink technique in which the multilink may include multiple frequency bands. That is, multilinks may represent links of several frequency bands and multiple multilinks within one frequency band at the same time. Two main multilink operations are being considered. It is contemplated that asynchronous operation of TX/RX and impossible synchronous operation are enabled simultaneously over multiple links. Hereinafter, the capability of enabling simultaneous reception and transmission on a plurality of links is referred to as STR (simultaneous transmission and reception), an STA having STR capability is referred to as STR MLD (multi-link device), and an STA not having STR capability is referred to as non-STR MLD.

In the following description, for convenience of explanation, it is described that an MLD (or a processor of the MLD) controls at least one STA, but is not limited thereto. As described above, the at least one STA may independently transmit and receive signals regardless of the MLD.

According to an embodiment, the AP MLD or the non-AP MLD may have a structure including a plurality of links. In other words, the non-AP MLD may support multiple links. The non-AP MLD may include a plurality of STAs. Multiple STAs may have links for each STA.

In the EHT standard (802.11 be standard), an MLD (multi-link device) structure in which one AP/non-AP MLD supports a plurality of links is regarded as a main technology. STAs included in the non-AP MLD may transmit information about other STAs in the non-AP MLD together through one link. Therefore, there is an effect of reducing overhead of frame exchange. In addition, there are effects of improving link use efficiency of STAs and reducing power consumption.

Here, the multilink may include multiple bands. That is, the multilink may represent both links of a plurality of frequency bands and a plurality of links within one frequency band.

Fig. 12 shows an example of the structure of the STA MLD.

Fig. 12 shows an example in which one STA MLD has three links. In 802.11be, for a single link to be established, one STA in STA MLD must provide information about the link or links it has.

Fig. 13 shows an example of basic multilink establishment.

Referring to fig. 13, the ap MLD has three links and announces information about them through a beacon frame or a probe response frame. Basically, as in the past, information about AP 1 (link 1) exists in a frame body transmitted by AP 1. Specifically, in 802.11be, one STA of the STA MLD is used for single multilink establishment, that is, in order to simultaneously associate (establish) a plurality of links through association frame exchange in one link, it is necessary to provide information about one or more links other than its own link. To provide this information, a multilink element (ML IE) has been defined, and the basic structure of the ML IE is shown in fig. 14.

The order, names, and sizes of the fields shown in fig. 14 may vary, and may exist as additional fields. Basically, the common information means common information between STAs in the MLD, and specific information about each STA is indicated in a per STA profile.

Referring to fig. 14, the multilink control field includes a type subfield and an MLD MAC address presence subfield. The common information field includes an MLD MAC address subfield. When the MLD MAC address presence subfield is set to 1 (or 0), the MAC address of the STA in the MLD may be included in the MLD MAC address subfield.

Fig. 15 shows a structure of a link information field of a multilink element.

Referring to fig. 15, when the optional subelement ID is 0, the link information field includes a per STA profile subfield, and when the optional subelement ID is 221, the link information field includes a vendor specific subfield. The optional subelement IDs for the multilink elements are defined as follows.

TABLE 1

Child element ID	Name of the name	Expandable device
			0	Per STA configuration file	Is that
1-220	Reservation of
			221	Vendor specific	Vendor defined
222-255	Reservation of

The link information field includes per STA profile subfields of other STAs (STAs operating in non-associated links) within the same MLD. Referring to fig. 14, assuming that the STA MLD includes STA 2 and STA 3, the link information field may include a per STA profile #2 subfield of STA 2 and a per STA profile #3 subfield of STA 3.

Basically, the common information field means common information between STAs in the MLD, and indicates specific information about each STA/link in a per STA profile including a link ID corresponding to the STA. Specifically, in the multilink element of the association request/response frame for multilink establishment (association), the complete profile of the per STA control field is set to 1, so that complete information of the AP MLD and the non-AP MLD must always be included.

Each of the information of AP 2 and AP 3 in fig. 13 is provided in the per STA profile subelement of the ML IE according to the description above. In the non-AP MLD of fig. 13, STA a requests configuration with AP 1 and STA B requests configuration with AP 2, AP MLD accepts this, and ML setup is successfully performed. However, there may be situations where the AP MLD does not accept some links. In this specification, a method of solving these cases is proposed. In addition, in the present specification, STA (MLD) may mean AP (MLD) or non-AP (MLD), a link (e.g., link 1 in fig. 13) through which an association request/response frame is transmitted is referred to as a transmission link (t_link), and links (e.g., link 2 and link 3 in fig. 13) through which no transmission is performed are referred to as non-transmission links (nt_link).

There may be several multilink establishment scenarios such as the following:

1) In the case where the AP MLD does not accept T_link but accepts one or more NT_links

According to the existing baseline, in this case, the association response will indicate the cause of the T_link rejection in the status code. Therefore, ML setup is not performed. However, for flexible ML setup, only nt_link can be accepted. Thus, a solution to this is as follows.

1-1) adding a New status_code

New state codes not previously present are added. For example, status code = reject_accept other links (code name may change). This means that it does not accept t_link, but accepts one or more nt_links. Thus, the association response includes the status code and the ML IE informs that the ML setup was successful, including per STA configuration files corresponding to the accepted AP/link.

Fig. 16 is a case where link 1 is not accepted based on the example AP MLD of fig. 13. In this case, link 1 is rejected by the new status code, as in 1-1), and only link 2 including per STA configuration file is accepted.

1-2) adding an indicator to the ML IE that means 1-1) status_code

The status code indicates the same content as before by placing the reason for rejecting T link. An indicator indicating acceptance of one or more nt_links is signaled in a multilink control field or common information field of an ML IE sent in an association response frame. (e.g., accepted AP present (1 bit))

Fig. 17 is a case where link 1 is not accepted based on the example AP MLD of fig. 13. In this case, as in 1-2), link 1 is rejected by the existing status code by indicating the value of the AP present field indicating acceptance of one or more nt_links as 1 in the multilink control field or common information field of the ML IE transmitted in the association response frame, and it informs of the per STA profile including link 2 (i.e., AP 2) for acceptance.

In the case of 1) above, the initial power management mode must be determined after ML establishment of the non-AP STA in the nt_link. That is, in power management mode, one link among a particular nt_link must be in active mode and one or more other nt_links must be in a doze state.

2) When the non-AP MLD does not request T_link

The non-AP MLD sends an association request frame to the T link, but the link is not included in the ML setup request. According to the existing baseline, T link that transmits an association request frame is always included in the ML setup request, and thus a solution including this is required.

2-1) adding instruction to ML IE to not request T_link

An indicator indicating that t_link is not requested and one or more nt_links are requested is signaled in a multilink control field or common information field of an ML IE transmitted in an association request frame. (e.g., no request to send a link (1 bit)). Specifically, in the association response, the status code may be set to 1-1 (status code = reject_accept other links) as successful or given above.

Fig. 18 is a case where link 1 is not requested based on the example non-AP MLD of fig. 13. In this case, 2-1) the method and the no-request-to-send link subfield are included in the multilink control field or the common information field of the ML IE and set to 1. The AP MLD knows this, accepts link 2 and performs ML setup.

3) If the AP MLD does not accept T link, it denies the multilink setup regardless of whether other NT links are accepted.

Currently, the 11be specification deals with the situation as in 3) as follows.

If the link that received the (re) association request frame is not acceptable to the AP MLD, the AP MLD treats the multi-link (re) establishment as a failure and does not accept the requested link.

In this case, the status code on the nt_link side requires a new indicator. In other words, acceptance is possible, but t_link is not accepted, so the multilink establishment fails. A code is required. Thus, the definition for this code is, for example:

the meaning of the code may have two options.

This means that even if the AP corresponding to NT link is operational, the link is rejected because of a multilink establishment failure.

In contrast to the following method, the STA control field may not be used.

Whether or not the corresponding NT link is working, it can tell that the multilink setup has failed. In this case, since it is not known whether nt_link is accepted, the information is insufficient compared to the above option.

In this case, as additional information, 1 bit (e.g., link SUCCESS) may be used in the STA control field of each per STA profile to indicate that the corresponding Link has been accepted.

Referring to fig. 19, even though the AP MLD can accept link 2, the status code of AP 2 (present in the full profile of per STA profile) indicates that the ML setup failed due to the request for link 1 being denied.

4) AP MLD accepts T link only but refuses multilink establishment due to other requested NT link refused

This means that the multilink establishment is successful only if at least 2 links are accepted. Thus, a new state code is required for t_link.

Only one link was successfully rejected: in other words, this means that the multilink establishment fails because only t_link is accepted and other nt_links are not accepted, just as the meaning of the code.

Referring to fig. 20, even if the AP MLD can accept the link 1, the status code of the AP 1 (existing in the association response frame body) indicates that the ML setup fails because only one T link is accepted because the request for the link 2 is rejected.

Hereinafter, the above-described embodiments will be described with reference to fig. 1 to 20.

The example of fig. 21 may be performed in a network environment supporting a next generation WLAN system (IEEE 802.11be or EHT WLAN system). The next generation wireless LAN system is a WLAN system enhanced with respect to the 802.11ax system, and thus can satisfy backward compatibility with the 802.11ax system.

In step S2110, a transmitting multi-link device (MLD) receives a first association request frame from a receiving MLD through a first link.

In step S2120, the transmitting MLD transmits a first association response frame to the receiving MLD over the first link.

At this time, the first link through which the first association request/response frame is transmitted may be named a transmission link (t_link), and the second link and the third link through which the first association request/response frame is not transmitted may be named a non-transmission link (nt_link).

That is, the present embodiment proposes the following method: by inserting a specific status code during the multilink establishment, information indicating that the multilink establishment has failed is transmitted without allowing transmission of the link, regardless of whether the non-transmission link is allowed. According to the proposed embodiment, after receiving the specific status code, the non-AP MLD may transmit an association request frame through the non-transmission link indicated by the specific status code at the next time of requesting the multilink setup. For example, the receiving MLD may receive the status code and confirm that the second link is an allowed link, and there is an effect that the second receiving STA may directly attempt multi-link establishment to the second transmitting STA through the second link without having to transmit the association request frame through the first link. Thus, there is an effect that the multilink configuration can be efficiently improved by the status code without additional overhead.

The first association request frame may include a second ML element. The second ML element includes a profile field of the second receiving STA. A connection to the second link is requested based on the profile field of the second receiving STA.

The profile field of the second receiving STA may include the integrity information of the second receiving STA, a first link Identifier (ID), and a first integrity profile. The first link ID may include an identifier of the second link. The value of the first complete profile may be set to 1. When the value of the first complete profile is set to 1, the complete information of the second receiving STA may be included in the profile field of the second receiving STA.

The profile field of the second transmitting STA may include the integrity information of the second transmitting STA, the second link ID, and the second integrity profile. The second link ID may include an identifier of the second link. The value of the second complete profile may be set to 1. The integrity information of the second transmitting STA may include a status code.

The transmitting MLD may further include a third transmitting STA operating on a third link. The receiving MLD may also include a third transmitting STA operating on a third link.

The first ML element may include a profile field of the third transmitting STA. The profile field of the third transmitting STA may include a separate status code. The individual status code may include information indicating that the ML setup has failed because the third link is allowed but the first link is not allowed. The individual status code may be set to decoded_multi-link setup_failed.

The example of fig. 22 may be performed in a network environment supporting a next generation WLAN system (IEEE 802.11be or EHT WLAN system). The next generation wireless LAN system is a WLAN system enhanced with respect to the 802.11ax system, and thus can satisfy backward compatibility with the 802.11ax system.

In step S2210, a receiving multi-link device (MLD) transmits a first association request frame to a transmitting MLD through a first link.

In step S2220, the receiving MLD receives the first association response frame from the transmitting MLD over the first link.

The technical features of the present disclosure may be applied to various apparatuses and methods. For example, the technical features of the present disclosure may be performed/supported by the apparatus of fig. 1 and/or 11. For example, the technical features of the present disclosure may be applied only to a portion of fig. 1 and/or 11. For example, the technical features of the present disclosure may be implemented based on the processing chips 114 and 124 of fig. 1, or based on the processors 111 and 121 and the memories 112 and 122, or based on the processor 610 and the memory 620 of fig. 11. For example, an apparatus according to the present disclosure transmits a first association request frame to a transmitting multi-link apparatus (MLD) over a first link; and receiving a first association response frame from the transmitting MLD over the first link.

The technical features of the present disclosure may be implemented based on a Computer Readable Medium (CRM). For example, CRM in accordance with the present disclosure is at least one computer-readable medium comprising instructions designed to be executed by at least one processor.

The CRM may store instructions to perform operations comprising: transmitting a first association request frame to a transmitting multi-link device (MLD) over a first link; and receiving a first association response frame from the transmitting MLD over the first link. The at least one processor may execute instructions stored in the CRM according to the present disclosure. The at least one processor associated with CRM of the present disclosure may be the processors 111, 121 of fig. 1, the processing chips 114, 124 of fig. 1, or the processor 610 of fig. 11. Further, CRM of the present disclosure may be memory 112, 122 of fig. 1, memory 620 of fig. 11, or a separate external memory/storage medium/disk.

The foregoing features of the present specification are applicable to various applications or business models. For example, the foregoing features may be applied to wireless communications of an Artificial Intelligence (AI) -enabled device.

Artificial intelligence refers to a research field about artificial intelligence or a method for creating artificial intelligence, and machine learning refers to a research field about a method for defining and solving various problems in the artificial intelligence field. Machine learning is also defined as an algorithm that improves operational performance through a steady operational experience.

An Artificial Neural Network (ANN) is a model used in machine learning, and may refer to a model that solves a problem as a whole, including artificial neurons (nodes) that form a network by combining synapses. The artificial neural network may be defined by a connection pattern between neurons of different layers, a learning process to update model parameters, and an activation function to generate output values.

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 the neurons. In an artificial neural network, each neuron may output a function value of an activation function of an input signal input through synapses, weights, and deviations.

Model parameters refer to parameters determined by learning and include weights of synaptic connections and deviations of neurons. Super-parameters refer to parameters to be set before learning in a machine learning algorithm and include learning rate, number of iterations, minimum batch size, and initialization function.

Learning the artificial neural network may be aimed at determining model parameters for minimizing the loss function. The loss function may be used as an index to determine optimal model parameters in learning the artificial neural network.

Machine learning can be classified into supervised learning, unsupervised learning, and reinforcement learning.

Supervised learning refers to a method of training an artificial neural network with labels given to training data, where when the training data is input to the artificial neural network, the labels may indicate correct answers (or result values) that the artificial neural network needs to infer. Unsupervised learning may refer to a method of training an artificial neural network without a tag given to training data. Reinforcement learning may refer to a training method for training agents defined in an environment to select actions or sequences of actions to maximize the jackpot per state.

Machine learning, which is implemented using a Deep Neural Network (DNN) including a plurality of hidden layers, among artificial neural networks is called deep learning, and deep learning is a part of machine learning. Hereinafter, machine learning is interpreted to include deep learning.

The foregoing technical features may be applied to wireless communication of a robot.

Robots may refer to machines that utilize their own capabilities to automatically process or operate a given task. In particular, a robot having a function of recognizing an environment and autonomously making a judgment to perform an operation may be referred to as an intelligent robot.

Robots can be classified into industrial, medical, home, military robots, etc., according to the purpose or field. The robot may include actuators or drives including motors to perform various physical operations, such as moving a robot joint. In addition, the movable robot may include wheels, brakes, propellers, etc. in the drive to travel on the ground or fly in the air by the drive.

The foregoing technical features may be applied to an apparatus supporting augmented reality.

Augmented reality is collectively referred to as Virtual Reality (VR), augmented Reality (AR), and Mixed Reality (MR). VR technology is a computer graphics technology that provides real world objects and background 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.

MR technology is similar to AR technology in that real and virtual objects can be displayed together. However, in the AR technique, a virtual object is used as a supplement to a real object, whereas in the MR technique, a virtual object and a real object are used as equivalent states.

XR technology may be applied to Head Mounted Displays (HMDs), head Up Displays (HUDs), mobile phones, tablets, laptops, desktop computers, televisions, digital signage, and the like. Devices employing XR technology may be referred to as XR devices.

The claims disclosed in this specification may be combined in various ways. For example, the technical features in the method claims of the present specification may be combined to be implemented as an apparatus, and the technical features in the apparatus claims of the present specification may be combined to be implemented by a method. Furthermore, the technical features in the method claims and the apparatus claims of the present specification may be combined to be implemented as an apparatus, and the technical features in the method claims and the apparatus claims of the present specification may be combined to be implemented by a method.

Claims

1. A method in a wireless local area network, WLAN, system, the method comprising the steps of:

Transmitting, by the receiving multi-link device MLD, a first association request frame to the transmitting MLD over the first link; and

receiving a first association response frame from the transmitting MLD over the first link by the receiving MLD,

wherein the transmitting MLD comprises a first transmitting station STA operating on the first link and a second transmitting STA operating on a second link,

wherein the receiving MLD comprises a first receiving STA operating on the first link and a second receiving STA operating on the second link,

wherein the first association response frame includes a first multilink ML element,

wherein the first ML element includes a profile field of the second transmitting STA,

wherein the profile field of the second transmitting STA includes a status code, and

wherein the status code includes information that ML setup has failed because the second link is allowed but the first link is not allowed.

2. The method of claim 1, wherein the first association request frame includes a second ML element,

wherein the second ML element includes a profile field of the second receiving STA,

wherein a connection to the second link is requested based on the profile field of the second receiving STA.

3. The method of claim 2, wherein the profile field of the second receiving STA comprises integrity information of the second receiving STA, a first link identifier ID, and a first integrity profile,

wherein the first link ID comprises an identifier of the second link,

wherein the value of the first complete profile is set to 1.

4. The method of claim 1, wherein the profile field of the second transmitting STA comprises complete information of the second transmitting STA, a second link ID, and a second complete profile,

wherein the second link ID includes an identifier of the second link,

wherein the value of the second complete profile is set to 1,

wherein the complete information of the second transmitting STA includes the status code.

5. The method of claim 1, the method further comprising:

transmitting, by the receiving MLD, a second association request frame to the transmitting MLD over the second link based on the status code;

receiving, by the receiving MLD, a second association response frame from the transmitting MLD over the second link; and

ML establishment with the transmitting MLD is performed by the receiving MLD based on the second link.

6. The method of claim 1, wherein the transmitting MLD further comprises a third transmitting STA operating on a third link,

wherein the receiving MLD further comprises a third transmitting STA operating on the third link.

7. A receiving multi-link device MLD in a wireless local area network WLAN system, the receiving MLD comprising:

a memory;

a transceiver; and

a processor operatively coupled to the memory and the transceiver,

wherein the processor is configured to:

transmitting a first association request frame to a transmitting MLD over a first link; and

receiving a first association response frame from the transmitting MLD over the first link,

8. A method in a wireless local area network, WLAN, system, the method comprising the steps of:

receiving, by the transmitting multi-link device MLD, a first association request frame from the receiving MLD over the first link; and

transmitting a first association response frame by the transmitting MLD to the receiving MLD over the first link,

9. The method of claim 8, wherein the first association request frame includes a second ML element,

10. The method of claim 9, wherein the profile field of the second receiving STA comprises integrity information of the second receiving STA, a first link identifier ID, and a first integrity profile,

wherein the first link ID comprises an identifier of the second link,

wherein the value of the first complete profile is set to 1.

11. The method of claim 8, wherein the profile field of the second transmitting STA comprises complete information of the second transmitting STA, a second link ID, and a second complete profile,

wherein the second link ID includes an identifier of the second link,

wherein the value of the second complete profile is set to 1,

12. The method of claim 8, the method further comprising:

receiving, by the transmitting MLD, a second association request frame from the receiving MLD over the second link based on the status code;

Transmitting, by the transmitting MLD, a second association response frame to the receiving MLD over the second link; and

ML establishment with the receiving MLD is performed by the transmitting MLD based on the second link.

13. The method of claim 8, wherein the transmitting MLD further comprises a third transmitting STA operating on a third link,

14. A transmitting multi-link device MLD in a wireless local area network WLAN system, the transmitting MLD comprising:

a memory;

a transceiver; and

a processor operatively coupled to the memory and the transceiver,

wherein the processor is configured to:

receiving a first association request frame from a receiving MLD over a first link; and

transmitting a first association response frame to the receiving MLD over the first link,

15. At least one computer-readable medium CRM storing instructions that, based on execution by at least one processor, perform operations comprising:

transmitting a first association request frame to a transmitting multi-link device MLD over a first link; and

16. An apparatus in a wireless local area network, WLAN, system, the apparatus comprising:

a memory; and

a processor operatively coupled to the memory,

wherein the processor is configured to: