Method and apparatus for roaming related identification in wireless LAN system

Abstract

The invention relates to roaming-related identification in a wireless LAN system. According to an embodiment of the present disclosure, a method performed by a mobile device in a wireless LAN system comprises the steps of: performing a connection procedure with a first access point (AP) affiliated to a first multilink device (MLD); obtaining a group identifier (ID) of a roaming group including the first MLD; transmitting a request frame for requesting roaming to a second MLD included in the roaming group, the request frame including the group ID; and performing roaming by means of the second MLD on the basis of receiving the response frame including the group ID.

Description

TECHNICAL FIELD

[0001] The disclosure relates to identification related to roaming in a wireless local area network (WLAN) system. BACKGROUND

[0002] Next generation Wi-Fi (e.g., IEEE 802.11be and / or later versions) aims to support ultra-high reliability of signaling to STAs, and various techniques are being studied to support high throughput, low latency, and extended coverage. To perform seamless roaming, identification related to roaming can be required. SUMMARY

[0003] TECHNICAL PROBLEM

[0004] Aspects of the disclosure aim to provide a method and apparatus for identification related to roaming in a WLAN system.

[0005] SOLUTION TO THE PROBLEM

[0006] According to an embodiment of the disclosure, a method performed by a mobile device in a wireless local area network (WLAN) system includes performing an association procedure with a first access point (AP) belonging to a first multi-link device (MLD); obtaining a group identifier (ID) of a roaming group including the first MLD; transmitting, to a second MLD included in the roaming group, a request frame requesting roaming, the request frame including the group ID; and performing roaming to the second MLD based on receiving a response frame including the group ID.

[0007] According to an embodiment of the disclosure, a method performed by a first access point (AP) belonging to a first multi-link device (MLD) in a wireless local area network (WLAN) system includes performing an association procedure with a mobile device; transmitting, to the mobile device, a group identifier (ID) of a roaming group including the first MLD; receiving, from the mobile device, a request frame requesting roaming to a second MLD included in the roaming group, the request frame including the group ID; and transmitting, to the mobile device, a response frame including the group ID so that the mobile device performs roaming to the second MLD.

[0008] In various embodiments, apparatuses implementing the above-described methods are provided.

[0009] ADVANTAGEOUS EFFECTS

[0010] The disclosure can have various advantageous effects.

[0011] For example, when a non-AP MLD roams, it can check whether a target AP MLD is included in the same roaming group as an AP MLD with which the non-AP MLD has currently established a link, and can increase the number of APs capable of performing roaming.

[0012] The advantageous effects that can be obtained through the specific embodiments of the present disclosure are not limited to the advantageous effects listed above. For example, there can be various technical effects that can be understood and / or derived by those of ordinary skill in the art from the present disclosure. Therefore, the specific effects of the present disclosure are not limited to those explicitly described herein, but can include various effects that can be understood or derived from the technical features of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 An example of a transmitting apparatus and / or a receiving apparatus of the present disclosure is illustrated.

[0014] Figure 2 is a conceptual diagram illustrating a structure of a wireless local area network (WLAN).

[0015] Figure 3 A general link setup procedure is exemplified.

[0016] Figure 4 An example of a multi-link (ML) is illustrated.

[0017] Figure 5 A modified example of a transmitting apparatus and / or a receiving apparatus of the present disclosure is illustrated.

[0018] Figure 6 An example of a physical protocol data unit or physical layer (PHY) protocol data unit (PPDU) transmitted / received by a STA of the present disclosure is illustrated.

[0019] Figure 7 A layout of a resource unit (RU) for a 20 MHz PPDU is exemplified.

[0020] Figure 8 A layout of a resource unit (RU) for a 40 MHz PPDU is exemplified.

[0021] Figure 9 A layout of a resource unit (RU) for an 80 MHz PPDU is exemplified.

[0022] Figure 10 Operations related to UL-MU are illustrated.

[0023] Figure 11 Examples of channels used / supported / defined within a 2.4 GHz band are exemplified.

[0024] Figure 12 Examples of channels used / supported / defined within a 5 GHz band are exemplified.

[0025] Figure 13 Examples of channels used / supported / defined within a 6 GHz band are exemplified.

[0026] Figure 14 An example of a media access control (MAC) frame header is shown.

[0027] Figure 15 A high layer architecture of an AP MLD is shown.

[0028] Figure 16 A deployment of an AP MLD for roaming is shown.

[0029] Figure 17 An example of a method for roaming related identification performed by a mobile device according to an embodiment of the disclosure is shown.

[0030] Figure 18 An example of a method for roaming related identification performed by an AP according to an embodiment of the disclosure is shown.

[0031] Figure 19 A first example of a format of an RNR IE including MLD roaming information according to an embodiment of the disclosure is shown.

[0032] Figure 20 A second example of a format of an RNR IE including MLD roaming information according to an embodiment of the disclosure is shown.

[0033] Figure 21 An example of a multi-link probe request / response based on group management AP MLD ID and / or group member AP MLD ID according to an embodiment of the disclosure is shown. DETAILED DESCRIPTION

[0034] In the disclosure, "A or B" can mean "only A", "only B", or "both A and B". In other words, in the disclosure, "A or B" can be interpreted as "A and / or B". For example, in the disclosure, "A, B, or C" can mean "only A", "only B", "only C", or "any combination of A, B, C".

[0035] A slash ( / ) or a comma used in the disclosure can mean "and / or". For example, "A / B" can mean "A and / or B". Thus, "A / B" can mean "only A", "only B", or "both A and B". For example, "A, B, C" can mean "A, B, or C".

[0036] In the disclosure, "at least one of A and B" can mean "only A", "only B", or "both A and B". In addition, in the disclosure, the expression "at least one of A or B" or "at least one of A and / or B" can be interpreted as "at least one of A and B".

[0037] The bracket used in the present disclosure can mean "for example". Specifically, when indicated as "control information (UHR-signal field)", it can mean that "UHR-signal field" is proposed as an example of "control information". In other words, the "control information" of the present disclosure is not limited to "UHR-signal field", and "UHR-signal field" can be proposed as an example of "control information". In addition, when indicated as "control information (i.e., UHR-signal field)", it can also mean that "UHR-signal field" is proposed as an example of "control information".

[0038] In addition, "one" as used in the present disclosure can mean "at least one" or "one or more". In addition, a term ending with "(s)" can mean "at least one" or "one or more"

[0039] In addition, the expression "based on" or "based on" or "according to" as used in the present disclosure means "at least partially based on", not "only based on".

[0040] The technical features described individually in one drawing in the present disclosure can be implemented individually, or can be implemented simultaneously.

[0041] The following examples of the present disclosure can be applied to various wireless communication systems. For example, the following examples of the present disclosure can be applied to a wireless local area network (WLAN) system. For example, the present disclosure can be applied to IEEE 802.11 a / g / n / ac / ax / be / bn standards. In addition, the examples of the present disclosure can also be applied to an enhanced ultra-high reliability (UHR) standard or a next-generation wireless LAN standard of IEEE 802.11 bn. In addition, the examples of the present disclosure can also be applied to a new WLAN standard enhanced from the EHT standard or the IEEE 802.11be standard. In addition, the examples of the present disclosure can be applied to a mobile communication system. For example, it can be applied to a long-term evolution (LTE) based mobile communication system, which depends on the third generation partnership project (3GPP) standard and is based on the evolution of LTE. In addition, the examples of the present disclosure can be applied to a communication system based on the 3GPP standard of the 5G NR standard.

[0042] Hereinafter, in order to describe the technical features of the present disclosure, technical features applicable to the present disclosure will be described.

[0043] Figure 1 Examples of a transmitting device and / or a receiving device of the present disclosure are shown.

[0044] In Figure 1 In the examples of the present disclosure, various technical features described below can be performed. Figure 1Refers to at least one station (STA). For example, the STAs 110 and 120 of the present disclosure can also be referred to as various terms such as a mobile terminal, a wireless device, a wireless transmit / receive unit (WTRU), a user equipment (UE), a mobile station (MS), a mobile subscriber unit, or simply a user. The STAs 110 and 120 of the present disclosure can also be referred to as various terms such as a network, a base station, a node B, an access point (AP), a repeater, a router, a relay, etc. The STAs 110 and 120 of the present disclosure can also be referred to as various names such as a receiving device, a transmitting device, a receiving STA, a transmitting STA, a receiving device, a transmitting device, etc.

[0045] For example, the STAs 110 and 120 can be used as an AP or a non-AP. That is, the STAs 110 and 120 of the present disclosure can be used as an AP and / or a non-AP. In the present disclosure, an AP can be indicated as an AP STA.

[0046] In addition to the IEEE 802.11 standard, the STAs 110 and 120 of the present disclosure can support various communication standards together. For example, a communication standard based on a 3GPP standard (e.g., an LTE, an LTE-A, a 5G NR standard), etc. can be supported. In addition, the STAs of the present disclosure can be implemented as various devices such as a mobile phone, a vehicle, a personal computer, etc. In addition, the STAs of the present disclosure can support communication for various communication services such as a voice call, a video call, data communication, and self-driving (autonomous driving), etc.

[0047] The STAs 110 and 120 of the present disclosure can include a medium access control (MAC) conforming to the IEEE 802.11 standard and a physical layer interface for a radio medium.

[0048] Hereinafter, the STAs 110 and 120 will be described with reference to a subgraph (a) of FIG. 1. Figure 1

[0049] The first STA 110 can include a processor 111, a memory 112, and a transceiver 113. The illustrated processor, memory, and transceiver can be implemented as separate chips, or at least two blocks / functions can be implemented through a single chip.

[0050] The transceiver 113 of the first STA performs a signal transmission / reception operation. Specifically, an IEEE 802.11 packet (e.g., IEEE 802.11a / b / g / n / ac / ax / be, etc.) can be transmitted / received.

[0051] ​For example, the first STA 110 can perform operations expected of an AP. For example, the processor 111 of the AP can receive signals through the transceiver 113, process the received (RX) signals, generate transmit (TX) signals, and provide control for signal transmission. The memory 112 of the AP can store signals received through the transceiver 113 (e.g., RX signals), and can store signals to be transmitted through the transceiver (e.g., TX signals).

[0052] For example, the second STA 120 can perform operations expected of a 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.) can be transmitted / received.

[0053] For example, the processor 121 of the non-AP STA can receive signals through the transceiver 123, process the RX signals, generate TX signals, and provide control for signal transmission. The memory 122 of the non-AP STA can store signals received through the transceiver 123 (e.g., RX signals), and can store signals to be transmitted through the transceiver (e.g., TX signals).

[0054] For example, operations of a device indicated as an AP in the disclosure described below can be performed in the first STA 110 or the second STA 120. For example, if the first STA 110 is an AP, operations of a device indicated as an AP can be controlled by the processor 111 of the first STA 110, and related signals can 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 operations of the AP or TX / RX signals of the AP can be stored in the memory 112 of the first STA 110. In addition, if the second STA 120 is an AP, operations of a device indicated as an AP can be controlled by the processor 121 of the second STA 120, and related signals can 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 operations of the AP or TX / RX signals of the AP can be stored in the memory 122 of the second STA 120.

[0055] For example, in the disclosure described below, the operation of the device indicated as a non-AP (or user STA) can 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 a non-AP can be controlled by the processor 121 of the second STA 120, and the related signal can 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 can 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 a non-AP can be controlled by the processor 111 of the first STA 110, and the related signal can 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 can be stored in the memory 112 of the first STA 110.

[0056] In the disclosure described below, the device referred to as a (transmitting / receiving) STA, a first STA, a second STA, STA1, STA2, an AP, a first AP, a second AP, AP1, AP2, a (transmitting / receiving) terminal, a (transmitting / receiving) device, a (transmitting / receiving) apparatus, a network, etc. can imply the STA 110 and 120 of Figure 1 . For example, the device indicated as (but not specifically numbered) a (transmitting / receiving) STA, a first STA, a second STA, STA1, STA2, an AP, a first AP, a second AP, AP1, AP2, a (transmitting / receiving) terminal, a (transmitting / receiving) device, a (transmitting / receiving) apparatus, a network, etc. can imply the STA 110 and 120 of Figure 1 . For example, in the following examples, the operation of various STAs to transmit / receive a signal (e.g., PPDU) can be performed in the transceiver 113 and 123 of Figure 1 . In addition, in the following examples, the operation of various STAs to generate a TX / RX signal or to perform data processing and calculation in advance for a TX / RX signal can be performed in the processor 111 and 121 of Figure 1The operations are executed in processors 111 and 121. Examples of operations for generating TX / RX signals or performing prior data processing and calculations may include: 1) operations to determine / obtain / configure / calculate / decode / encode bit information of subfields (SIG, STF, LTF, data) included in the PPDU; 2) operations to determine / configure / obtain time resources or frequency resources (e.g., subcarrier resources) for the subfields (SIG, STF, LTF, data) included in the PPDU; 3) operations to determine / configure / obtain specific sequences (e.g., pilot sequences, STF / LTF sequences, additional sequences applied to SIG) for the subfields (SIG, STF, LTF, data) included in the PPDU; 4) power control operations and / or power-saving operations applied to the STA; and 5) operations related to the determination / obtaining / configuration / decoding / encoding of the ACK signal. Additionally, in the following examples, various information used by various STAs to determine / obtain / configure / calculate / decode / decode the TX / RX signal (e.g., information related to fields / subfields / control fields / parameters / power, etc.) may be stored in the STA. Figure 1 In memory 112 and 122.

[0057] Figure 1 The aforementioned device / STA in subgraph (a) can be as follows Figure 1 The subgraph (b) is modified as shown below. In the following text, the modifications will be based on... Figure 1 The subgraph (b) is used to describe STA 110 and STA 120 of this disclosure.

[0058] For example, Figure 1 The transceivers 113 and 123 shown in subgraph (b) can perform operations with Figure 1 The transceiver shown in subgraph (a) has the same function as the aforementioned transceiver. For example, 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 sub-figure (b) can perform operations related to Figure 1 The processors 111 and 121 and the memories 112 and 122 shown in sub-figure (a) have the same functions.

[0059] The mobile terminal, wireless device, wireless transceiver unit (WTRU), user equipment (UE), mobile station (MS), mobile subscriber unit, user, user STA, network, base station, node B, access point (AP), repeater, router, relay, receiving unit, transmitting unit, receiving STA, transmitting STA, receiving device, transmitting device, receiving device and / or transmitting device described below may mean Figure 1The STA 110 and 120 shown in subgraphs (a) / (b) may mean, or Figure 1 The processing chips 114 and 124 are shown in sub-figure (b). That is, the technical features of this disclosure can be... Figure 1 It can be performed in STA 110 and 120 as shown in subgraphs (a) / (b), or it can be performed only in Figure 1 The processing chips 114 and 124 shown in sub-diagram (b) are executed Figure 1 Transceivers 113 and 123 are shown in sub-diagrams (a) and (b). For example, the technical features of transmitting control signals by a STA can be understood as being achieved through... Figure 1 The transceiver 113 illustrated in subgraphs (a) / (b) transmits in Figure 1 The technical features of the control signals generated in processors 111 and 121 are illustrated in sub-figures (a) and (b). Alternatively, the technical features of the STA transmitting control signals can be understood as follows: Figure 1 The technical features of generating control signals to be transmitted to transceivers 113 and 123 in processing chips 114 and 124 are shown in sub-figure (b).

[0060] For example, the technical characteristics of receiving STA control signals can be understood as through... Figure 1 The technical features of transceivers 113 and 123 receiving control signals are shown in sub-figure (a). Alternatively, the technical features of receiving STA control signals can be understood as being achieved through... Figure 2 Processors 111 and 121 shown in subgraph (a) obtain Figure 2 The technical features of the control signals received in transceivers 113 and 123 shown in sub-figure (a) are illustrated. Alternatively, the technical features of receiving control signals by the STA can be understood as being achieved through... Figure 2 The processing chips 114 and 124 shown in sub-figure (b) obtain Figure 2 Technical features of the control signals received in transceivers 113 and 123 as shown in sub-figure (b).

[0061] refer to Figure 2 Subgraph (b), software codes 115 and 125 can be included in memories 112 and 122. Software codes 115 and 125 can include instructions for controlling the operation of processors 111 and 121. Software codes 115 and 125 can be included in various programming languages.

[0062] Figure 2 The processors 111 and 121 or processing chips 114 and 124 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, Figure 3The processors 111 and 121 or processing chips 114 and 124 of the electronic device 100 can include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modulator and demodulator (modem). For example, Figure 3 The processors 111 and 121 or processing chips 114 and 124 can be a series of processors manufactured by Qualcomm®, a series of processors manufactured by Samsung®, a series of processors manufactured by Apple®, a series of processors manufactured by MediaTek®, a series of processors manufactured by Intel®, or processors enhanced from these processors.

[0063] In the disclosure, an uplink can mean a link for communication from a non-AP STA to an AP STA, and an uplink PPDU / packet / signal, etc. can be transmitted through the uplink. In addition, in the disclosure, a downlink can mean a link for communication from an AP STA to a non-AP STA, and a downlink PPDU / packet / signal, etc. can be transmitted through the downlink.

[0064] Figure 3 is a conceptual diagram illustrating a structure of a wireless local area network (WLAN).

[0065] Figure 4 The upper portion of illustrates a structure of an Institute of Electrical and Electronics Engineers (IEEE) 802.11 infrastructure basic service set (BSS).

[0066] Referring to Figure 4 The upper portion of the wireless LAN system can include one or more infrastructure BSSs 200 and 205 (hereinafter, referred to as a BSS). The BSSs 200 and 205, which are a set of APs and STAs (e.g., an access point (AP) 225 and a station (STA1) 200-1) that successfully synchronize to communicate with each other, are not a concept indicating a specific area. The BSS 205 can include one or more STAs 205-1 and 205-2 that can join one AP 230.

[0067] The BSS can include at least one STA, an AP that provides a distributed service, and a distribution system (DS) 210 that connects a plurality of APs.

[0068] The distributed system 210 can implement an extended service set (ESS) 240 that is extended by connecting a plurality of BSSs 200 and 205. The ESS 240 can be used as a term indicating one network configured by connecting one or more APs 225 or 230 via the distributed system 210. The APs included in one ESS 240 can have the same service set identification (SSID).

[0069] The portal 220 can be used as a bridge that connects a wireless LAN network (IEEE 802.11) and another network (for example, 802.X).

[0070] In the upper part of Figure 4 In the BSS shown in the upper part of

[0071] Figure 4 The lower part of

[0072] Referring to Figure 4 The lower part of

[0073] Figure 4 A general link establishment procedure is illustrated.

[0074] In S310, the STA can perform a network discovery operation. The network discovery operation can include a scanning operation of the STA. That is, in order to access a network, the STA needs to discover a network participating in the network. The STA needs to identify a compatible network before joining a wireless network, and a process of identifying a network present in a specific area is called scanning. The scanning method includes active scanning and passive scanning.

[0075] Figure 4Network discovery operations including active scanning processing are exemplified. 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 APs are present around while moving to a 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 can be the STA that has sent the last beacon frame in the BSS of the channel being scanned. In a BSS, since the AP sends the beacon frame, the AP is the responder. In an IBSS, since the STAs in the IBSS take turns sending the beacon frame, 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 can store the BSS related information included in the received probe response frame, can move to the next channel (e.g., channel 2), and can perform the scan by the same method (e.g., sending a probe request via channel 2 and receiving a probe response).

[0076] Although Figure 4 Scanning can be performed by a passive scanning method, which is not shown in FIG. 3. 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 presence of a wireless network and to enable the STA performing the scan to find the wireless network and join the wireless network. In a BSS, the AP is used to periodically send the beacon frame. In an IBSS, the STAs in the IBSS take turns sending the beacon frame. Upon receiving the beacon frame, the STA performing the scan stores information about the BSS included in the beacon frame and records the beacon frame information in each channel while moving to another channel. The STA receiving the beacon frame can store the BSS related information included in the received beacon frame, can move to the next channel, and can perform the scan in the next channel by the same method.

[0077] After discovering the network, the STA can perform an authentication process in S320. The authentication process can be referred to as a first authentication process to clearly distinguish from a security setup operation in S340 later. The authentication process in S320 can 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 for authentication request / response is a management frame.

[0078] The authentication frame can include information about an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a robust security network (RSN), and a finite cyclic group.

[0079] The STA can send the authentication request frame to the AP. The AP can determine whether to allow authentication of the STA based on the information included in the received authentication request frame. The AP can provide the STA with the authentication process result via the authentication response frame.

[0080] When the STA is successfully authenticated, the STA can perform association processing in S330. The association processing includes processing 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 can include information on various capabilities, a beacon listen interval, a service set identifier (SSID), a supported rate, a supported channel, an RSN, a mobility domain, a supported operating class, a traffic indication map (TIM) broadcast request, and an interworking service capability. For example, the association response frame can include information on various capabilities, a status code, an association ID (AID), a supported rate, an enhanced distributed channel access (EDCA) parameter set, a received channel power indicator (RCPI), a received signal to noise indicator (RSNI), a mobility domain, a super interval (association recovery time), an overlapping BSS scan parameter, a TIM broadcast response, and a QoS map.

[0081] In S340, the STA can perform security establishment processing. The security establishment processing in S340 can include processing in which a private key is established through a four-way handshake (for example, through an extensible authentication protocol over LAN (EAPOL) frame).

[0082] Hereinafter, a multi-link (ML) is explained.

[0083] Definitions of terms related to a multi-link are as follows:

[0084] - A multi-link device (MLD) can support multiple affiliated STAs, can operate using one or more affiliated STAs, and provides a single MAC data service and a single MAC service access point (SAP) to a logical link control (LLC) lower layer.

[0085] - Multi-link operation (MLO) can refer to tasks such as discovery, authentication, multi-link establishment, and exchange of frames between two MLDs;

[0086] - An affiliated STA is a STA that provides link-specific lower layer MAC and PHY services within an MLD, and can be an access point (AP) STA or a non-access point (non-AP) STA;

[0087] - An AP MLD is an MLD in which each affiliated STA is an AP STA;

[0088] - A non-AP MLD is an MLD in which each affiliated STA is a non-AP STA;

[0089] - An affiliated AP is an AP STA affiliated with an AP MLD;

[0090] - An affiliated non-AP STA is a non-AP STA affiliated with a non-AP MLD.

[0091] Figure 4 An example of multi-link (ML) is shown.

[0092] like Figure 4 As illustrated, multiple multi-link devices (MLDs) can communicate via a remote link. MLDs can be classified as AP MLDs, which include multiple AP STAs, and non-AP MLDs, which include multiple non-AP STAs. That is, an AP MLD may include a member AP (i.e., an AP STA), and a non-AP MLD may include a member STA (i.e., a non-AP STA or a user STA).

[0093] Multiple links can include a first link and a second link, and different channel / subchannel / frequency resources can be allocated to the first link and the second link. The first and second multiple links can be identified by a 4-bit (or other n-bit) link ID. The first and second links can be configured in the same 2.4 GHz, 5 GHz, or 6 GHz frequency band. Alternatively, the first and second links can be configured in different frequency bands.

[0094] Figure 1 The AP MLD includes three subordinate APs. Figure 2 In the example, AP1 can operate in the 2.4 GHz band, AP2 can operate in the 5 GHz band, and AP3 can operate in the 6 GHz band. Figure 4 In the example, the first link in which AP1 and non-AP1 operate can be defined as a channel / subchannel / frequency resource within the 2.4 GHz band. Furthermore, in Figure 1 In the example, the second link in which AP2 and non-AP2 operate can be defined as a channel / subchannel / frequency resource within the 5 GHz band. Furthermore, in Figure 2 In the example, the third link in which AP3 and non-AP3 operate can be defined as a channel / subchannel / frequency resource within the 6GHz band.

[0095] exist Figure 4 In the example, AP1 can initiate the multi-link establishment process (ML establishment process) by sending an association request frame to a non-AP STA1. Figure 5 In the example, a non-AP STA1 can send an association response frame in response to an association request frame. Figure 1 to Figure 4 The individual APs shown (e.g., AP1 / 2 / 3) can be compared with... Figure 5 and / or Figure 5 The APs shown are the same, and Figure 1 The various non-APs shown (e.g., non-AP1 / 2 / 3) can be compared with... Figure 5 and / orFigure 5 The STAs shown (i.e., user STAs or non-AP STAs) are the same.

[0096] Once the ML setup is complete, an enabled link for ML communication can be determined. The STAs can exchange frames over at least one of the multiple links determined as the enabled link. For example, the enabled link can be used for at least one of management frames, control frames, or data frames.

[0097] If a single STA supports multiple links, the transmission and reception apparatuses supporting each link can operate as a single logical STA. For example, a single STA supporting two links can be represented by a single ML device (MLD) including a first STA for a first link and a second STA for a second link. For example, a single AP supporting two links can be represented by a single AP MLD including a first AP for a first link and a second AP for a second link. Also, a non-AP supporting two links can be represented by a non-AP MLD including a first STA for a first link and a second STA for a second link.

[0098] The following describes more specific features related to ML setup.

[0099] An MLD (AP MLD and / or non-AP MLD) can transmit information about links that the MLD is capable of supporting through ML setup. The information about the links can be configured in various ways. For example, the information about the links can include at least one of the following: 1) information about whether the MLD (or STA) supports simultaneous reception / transmission operation; 2) information about the number / upper limit of uplink / downlink supported by the MLD (or STA); 3) information about the location / band / resource of the uplink / downlink supported by the MLD (or STA); 4) information about a frame type (management frame, control frame, data frame, etc.) that is available or preferred in at least one uplink / downlink; 5) information about an ACK policy that is available or preferred in at least one uplink / downlink; 6) information about a traffic identifier (TID) that is available or preferred in at least one uplink / downlink. The TID is related to the priority of traffic data and is represented as eight types of values according to the existing wireless LAN standard. That is, according to the existing wireless LAN standard, eight TID values corresponding to four access categories (ACs) (AC_BK (background), AC_BE (best effort), AC_VI (video), AC_VO (voice)) can be defined.

[0100] For example, all TIDs can be preconfigured to map to uplink / downlink. Specifically, if negotiation is not established through ML, all TIDs are used for ML communication. If uplink / downlink and TID mapping is negotiated through additional ML establishment, negotiated TIDs can be used for ML communication.

[0101] Through ML establishment, multiple links for use by a transmitting and receiving MLD participating in ML communication can be established, which can be referred to as "enabled links". The "enabled links" can be named in various ways, such as "first link", "second link", "transmitting link", or "receiving link".

[0102] After ML establishment is completed, the MLD can update the ML establishment. For example, if link information needs to be updated, the MLD can transmit information about a new link. The information about the new link can be transmitted based on at least one of a management frame, a control frame, or a data frame.

[0103] The specific features of the present disclosure are not limited to Figure 1 the specific features of the present disclosure. That is, the number of links can be defined in various ways, and the multiple links can be defined in various ways within at least one frequency band.

[0104] Figure 5 A modified example of the transmitting apparatus and / or the receiving apparatus of the present disclosure is illustrated.

[0105] Figure 1 The apparatus (e.g., AP STA, non-AP STA) illustrated in Figure 5 may be modified as illustrated in Figure 1 The transceiver 530 of the present disclosure can be the same as the transceiver 113, 123 of Figure 5 . The transceiver 530 of the present disclosure can include a receiver and a transmitter. Figure 1 The transceiver 530 of the present disclosure can include a receiver and a transmitter.

[0106] Figure 5 The processor 510 of the present disclosure can be the same as the processor 111, 121 of Figure 5 . Alternatively, Figure 6 The processor 510 of the present disclosure can be the same as the processing chip 114, 124 of Figure 6 .

[0107] Figure 6 The memory 150 of the present disclosure can be the same as the memory 112, 122 of Figure 6 . Alternatively, Figure 6 The memory 150 of the present disclosure can be a separate external memory different from the memory 112, 122 of Figure 6 .

[0108] Referring to Figure 6The power management module 511 manages power for the processor 510 and / or the transceiver 530. The battery 512 supplies power to the power management module 511. The display 513 outputs results processed by the processor 510. The keypad 514 receives inputs to be used by the processor 510. The keypad 514 can be shown on the display 513. The SIM card 515 can be an integrated circuit that is used to securely store the international mobile subscriber identity (IMSI) and its related key, which are used to identify and authenticate subscribers on mobile devices such as mobile phones and computers.

[0109] Referring to Figure 6 , the speaker (540) can output sound-related results processed by the processor 510. The microphone (541) can receive sound-related inputs to be used by the processor 510.

[0110] Figure 6 An example of a physical protocol data unit or physical layer (PHY) protocol data unit (PPDU) transmitted / received by the STA of the disclosure is shown.

[0111] The STA (e.g., AP STA, non-AP STA, AP MLD, non-AP MLD) of the disclosure can transmit and / or receive a PPDU of Figure 6 The PPDU described in the disclosure can have a structure of, for example, Figure 6 In addition, the PPDU described in the disclosure can be referred to by various names such as a transmission PPDU, a reception PPDU, a first type or an Nth type PPDU, etc. The PPDU described in the disclosure can be used in a WLAN system defined according to IEEE 802.11bn and / or a next-generation WLAN system that improves IEEE 802.11bn.

[0112] Figure 6 The PPDU of Figure 6 Examples of Figure 6 If the example of Figure 6 The UHR-SIG of Figure 6 If the PPDU of Figure 6 is used for a trigger-based (TB) mode, the UHR-SIG of may be omitted. In other words, a STA that has received a trigger frame for uplink-MU (UL-MU) communication can transmit a PPDU in which the UHR-SIG is omitted in the example of

[0113] InFigure 6 In this case, the L-STF or UHR-LTF can be referred to as a preamble or a physical preamble, and can be generated / received / acquired / decoded in a physical layer (including in a transmitting / receiving STA).

[0114] Figure 7 Each block illustrated in the above can be referred to as a field / subfield / signal, etc. The names of these fields / subfields / signals can be Legacy Short Training Field (L-STF), Legacy Long Training Field (L-LTF), Legacy Signal (L-SIG), Repeated L-SIG (RL-SIG), Universal Signal (U-SIG), UHR Signal (UHR-SIG), etc., as illustrated in Figure 7

[0115] Figure 7 The subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields of the above can be determined as 312.5 kHz, and the subcarrier spacing of the UHR-STF, UHR-LTF, and Data (Data) fields can be determined as 78.125 kHz. That is, the tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and UHR-SIG fields can be expressed in units of 312.5 kHz, and the tone index (or subcarrier index) of the UHR-STF, UHR-LTF, and Data fields can be expressed in units of 78.125 kHz.

[0116] In the PPDU of the above Figure 7 , the L-LTF and L-STF can be the same as those in the conventional field (e.g., non-HT LTF and non-HT STF defined in the conventional WLAN standard).

[0117] Figure 7 ​The L-SIG field of the HE-SIG-A field can include, for example, 24 bits of bit information. For example, the 24 bits of bit information can 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 can include information related to a length or duration of the PPDU. For example, the 12-bit length field can be determined based on a type of the PPDU. For example, when the PPDU is a non-high throughput (HT), high throughput (HT), very high throughput (VHT) PPDU, an extremely high throughput (EHT) PPDU, or a UHR PPDU, a value of the length field can be determined as a multiple of 3. For example, when the PPDU is a HE PPDU, the length field can be determined as a "multiple of 3" + 1 or a "multiple of 3" + 2. In other words, for a non-HT, HT, VHT PPDU, an EHT PPDU, or a UHR PPDU, a value of the length field can be determined as a multiple of 3, and for a high efficiency (HE) PPDU, a value of the length field can be determined as a "multiple of 3" + 1 or a "multiple of 3" + 2. In other words, the LENGTH field in the UHR PPDU is set to a value satisfying a condition that when the LENGTH is divided by 3, the remainder is 0.

[0118] For example, the (non-AP and AP) STA can apply BCC encoding based on a 1 / 2 coding rate to the 24 bits of bit information of the L-SIG field. Thereafter, the transmitting STA can obtain 48 bits of BCC encoded bits. BPSK modulation can be applied to the 48 bits of encoded bits, thereby generating 48 BPSK symbols. The transmitting STA can map the 48 BPSK symbols to positions except for pilot subcarriers {subcarrier indices -21, -7, +7, +21} and a DC subcarrier {subcarrier index 0}. As a result, the 48 BPSK symbols can be mapped to subcarrier indices -26 to -22, -20 to -8, -6 to -1, +1 to +6, +8 to +20, and +22 to +26. The transmitting STA can additionally map signals of {-1, -1, -1, 1} to subcarrier indices {-28, -27, +27, +28}. The foregoing signals can be used for channel estimation in a frequency domain corresponding to {-28, -27, +27, +28}.

[0119] For example, the (non-AP and AP) STAs can generate an RL-SIG generated in the same manner as the L-SIG. BPSK modulation can be applied to the RL-SIG. Based on the presence of the RL-SIG, the (non-AP and AP) STAs can know that the RX PPDU is a HE PPDU, an EHT PPDU, or a UHR PPDU. In other words, if the RL-SIG is present, the receiving (non-AP and AP) STAs can know that the received PPDU is one of a HE PPDU, an EHT PPDU, and a UHR PPDU. In other words, if the RL-SIG is not present, the receiving (non-AP and AP) STAs can know that the received PPDU is one of a non-HT PPDU, a HT PPDU, and a VHT PPDU. In other words, the RL-SIG field is a repetition of the L-SIG field and is used to distinguish a UHR PPDU from a non-HT PPDU, a HT PPDU, and a VHT PPDU.

[0120] A universal SIG (U-SIG) can be inserted after the RL-SIG of Figure 7 The U-SIG can be referred to in 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, a common control field, a common control field, and the like.

[0121] The U-SIG can include N bits of information and can include information to identify a type of the EHT PPDU. For example, the U-SIG can be configured based on two symbols (e.g., two consecutive OFDM symbols). Each symbol (e.g., OFDM symbol) for the U-SIG can have a duration of 4 μβ. Each symbol of the U-SIG can be used to transmit 26 bits of information. For example, each symbol of the U-SIG can be transmitted / received based on 52 data tones and 4 pilot tones.

[0122] Through the U-SIG, for example, A-bit information (e.g., 52 un-encoded bits) can be transmitted. A first symbol of the U-SIG can transmit a first X-bits of the A-bit information (e.g., 26 un-encoded bits), and a second symbol of the U-SIG can transmit a remaining Y-bits of the A-bit information (e.g., 26 un-encoded bits). For example, a transmitting STA can obtain the 26 un-encoded bits included in each U-SIG symbol. The transmitting STA can perform convolutional encoding (i.e., BCC encoding) based on a rate of R = 1 / 2 to generate 52 encoded bits, and can perform interleaving on the 52 encoded bits. The transmitting STA can perform BPSK modulation on the interleaved 52 encoded bits to generate 52 BPSK symbols to be allocated to each U-SIG symbol. One U-SIG symbol can 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 can be transmitted based on the remaining tones (subcarriers) i.e., tones -21, -7, +7, +21, except for the pilot tones.

[0123] For example, the A-bit information (e.g., 52 un-encoded bits) generated by the U-SIG can 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 can be transmitted through the second symbol of the U-SIG. The CRC field can be generated based on the 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 can be generated based on a conventional CRC calculation algorithm. In addition, the tail field can be used to terminate a trellis of a convolutional decoder, and can be set to, for example, "000000."

[0124] The A-bit information (e.g., 52 un-encoded bits) transmitted by the U-SIG (or U-SIG field) can be divided into version-independent bits and version-dependent bits. For example, the version-independent bits can have a fixed or variable size. For example, the version-independent bits can be allocated only to the first symbol of the U-SIG, or the version-independent bits can 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 can be referred to in various terms such as first control bits, second control bits, etc.

[0125] For example, the version-independent bits of the U-SIG can include a 3-bit PHY version identifier. For example, the 3-bit PHY version identifier can include information related to the PHY version of the TX / RX PPDU. For example, a first value (e.g., 000 value) of the 3-bit PHY version identifier can indicate that the TX / RX PPDU is an EHT PPDU. Also, a second value (e.g., 001 value) of the 3-bit PHY version identifier can indicate that the TX / RX PPDU is a UHR PPDU.

[0126] In other words, when the (AP / non-AP) STA transmits the EHT PPDU, the 3-bit PHY version identifier can be set to the first value, and when the (AP / non-AP) STA transmits the UHR PPDU, the 3-bit PHY version identifier can be set to the second value. In other words, the receiver (AP / non-AP) STA can determine that the received PPDU is the EHT PPDU based on the PHY version identifier having the first value, and can determine that the received PPDU is the UHR PPDU based on the PHY version identifier having the second value.

[0127] For example, the version-independent bits of the U-SIG can include a 1-bit UL / DL flag field. A first value of the 1-bit UL / DL flag field is related to UL communication, and a second value of the UL / DL flag field is related to DL communication.

[0128] For example, the version-independent bits of the U-SIG can include information related to a transmission opportunity (TXOP) length and information related to a BSS color ID.

[0129] For example, if the UHR PPDU is classified into various types (e.g., a type related to SU transmission (performed based on UL or DL), a type related to DL transmission, a type related to NDP transmission, a type related to DL non-MU-MIMO, a type related to DL MU-MIMO, a type related to multi-AP operation, a type related to coordinated beamforming (CBF), spatial reuse (SR), a type related to coordinated OFDMA (C-OFDMA), a type related to coordinated TDMA (CTDM)), information (e.g., 2-bit or 3-bit information) about the type of the UHR PPDU can be included in the version-dependent bits of the U-SIG.

[0130] For example, the U-SIG can include: 1) a bandwidth field including information related to a bandwidth; 2) a field including information related to a modulation and demodulation scheme (MCS) applied to the UHR-SIG; 3) an indication field including information related to whether a dual subcarrier modulation (DCM) scheme is applied to the UHR-SIG; 4) a field including information related to a number of symbols used for the UHR-SIG; 5) a field including information related to whether the UHR-SIG is generated across a full band; 6) a field including information related to a type of UHR-LTF / STF; and 7) information related to a field indicating a UHR-LTF length and a CP length.

[0131] Preamble puncturing can be applied to the PPDU of Figure 8 Preamble puncturing means that puncturing is applied to a portion of a full band (e.g., a secondary 20 MHz band). For example, when an 80 MHz PPDU is transmitted, a STA can apply puncturing to a secondary 20 MHz band within the 80 MHz band, and can transmit the PPDU through only a primary 20 MHz band and a secondary 40 MHz band.

[0132] For example, a pattern of preamble puncturing can be pre-configured. For example, when a first puncturing pattern is applied, puncturing can be applied only to a secondary 20 MHz band within an 80 MHz band. For example, when a second puncturing pattern is applied, puncturing can be applied only to any one of two secondary 20 MHz bands included in a secondary 40 MHz band within an 80 MHz band. For example, when a third puncturing pattern is applied, puncturing can be applied only to a secondary 20 MHz band included in a primary 80 MHz band within a 160 MHz band (or an 80+80 MHz band). For example, when a fourth puncturing pattern is applied, puncturing can be applied to at least one 20 MHz channel not belonging to a primary 40 MHz band in the presence of the primary 40 MHz band included in an 80 MHz band within a 160 MHz band (or an 80+80 MHz band).

[0133] Information related to preamble puncturing applied to the PPDU can be included in the U-SIG and / or the UHR-SIG. For example, a first field of the U-SIG can include information related to a contiguous bandwidth, and a second field of the U-SIG can include information related to preamble puncturing applied to the PPDU.

[0134] For example, the U-SIG and the UHR-SIG can include information related to the preamble puncturing based on the following method. When the bandwidth of the PPDU exceeds 80 MHz, the U-SIG can be separately configured in units of 80 MHz. For example, when the bandwidth of the PPDU is 160 MHz, the PPDU can include a first U-SIG for a first 80 MHz frequency band and a second U-SIG for a second 80 MHz frequency band. In this case, a first field of the first U-SIG can include information related to the 160 MHz bandwidth, and a second field of the first U-SIG can include information related to the preamble puncturing applied to the first 80 MHz frequency band (i.e., information related to the preamble puncturing pattern). Also, a first field of the second U-SIG can include information related to the 160 MHz bandwidth, and a second field of the second U-SIG can include information related to the preamble puncturing applied to the second 80 MHz frequency band (i.e., information related to the preamble puncturing pattern). Meanwhile, the UHR-SIG continuous to the first U-SIG can include information related to the preamble puncturing applied to the second 80 MHz band (i.e., information related to the preamble puncturing pattern), and the UHR-SIG continuous to the second U-SIG can include information related to the preamble puncturing applied to the first 80 MHz frequency band (i.e., information related to the preamble puncturing pattern).

[0135] Additionally or alternatively, the U-SIG and the UHR-SIG can include information related to the preamble puncturing based on the following method. The U-SIG can include information related to the preamble puncturing for all frequency bands (i.e., information related to the preamble puncturing pattern). That is, the UHR-SIG can not include information related to the preamble puncturing, and only the U-SIG can include information related to the preamble puncturing (i.e., information related to the preamble puncturing pattern).

[0136] The U-SIG can be configured in units of 20 MHz. For example, when an 80 MHz PPDU is configured, the U-SIG can be duplicated. That is, four identical U-SIGs can be included in the 80 MHz PPDU. The PPDU exceeding the 80 MHz bandwidth can include different U-SIGs.

[0137] Figure 7 The UHR-SIG in the U-SIG can include control information for the receiving STA. The UHR-SIG can be transmitted through at least one symbol, and one symbol can have a length of 4 µs. Information related to the number of symbols used for the UHR-SIG can be included in the U-SIG.

[0138] The UHR-SIG field provides additional signals to the U-SIG field to enable the STA to interpret / decode the UHR PPDU. The UHR-SIG field can include U-SIG overflow bits that are generally applied to all users. In addition, the UHR-SIG field includes resource allocation information so that the STA can find resources used in the fields including the data field / UHR-STF / UHR-LTF, i.e., the UHR modulation field of the UHR PPDU.

[0139] The frequency resources of the UHR-LTF, UHR-STF, and data field illustrated in Figure 8 may be determined based on an RU (Resource Unit) defined by a plurality of subcarriers / tone.

[0140] Figure 8 A layout of a resource unit (RU) for a 20 MHz PPDU is illustrated. That is, the UHR-LTF, UHR-STF, and / or data field included in the 20 MHz PPDU can be transmitted / received through at least one of various RUs defined in Figure 7 .

[0141] As illustrated in the uppermost part of Figure 9 , 26 units, i.e., units corresponding to 26 tones, can be arranged. Six tones can be used for a guard band in the leftmost band of the 20 MHz band, and five tones can be used for a guard band in the rightmost band of the 20 MHz band. In addition, seven DC tones can be inserted in the center band, i.e., the DC band, and 26 units corresponding to 13 tones in each of the left and right sides of the DC band can be arranged. 26 units, 52 units, and 106 units can be allocated to other bands. The respective units can be allocated to a receiving STA, i.e., a user.

[0142] Figure 10 The layout of the RU in Figure 10 may not only be used for multi-user (MU) but also for single user (SU), in which case one 242 unit can be used and three DC tones can be inserted, as illustrated in the lowermost part of

[0143] Although Figure 11RUs of various sizes, i.e., 26-RU, 52-RU, 106-RU, and 242-RU, are proposed, but a specific size of RU can be extended or added. Accordingly, the present embodiment is not limited to each RU of a specific size (i.e., the number of corresponding tones). In the present specification, N-RU can be expressed as N-tone RU, etc. For example, 26-RU can be expressed as 26-tone RU.

[0144] Figure 11 A layout of resource units (RUs) for a 40 MHz PPDU is exemplified.

[0145] With the use of RUs of various sizes Figure 12 Similarly, in the example of Figure 12 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, etc. can be used. Further, five DC tones can be inserted in the center frequency, 12 tones can be used for a guard band in the leftmost band of the 40 MHz band, and 11 tones can be used for a guard band in the rightmost band of the 40 MHz band.

[0146] As shown in Figure 13 , when the layout of RUs is used for a single user, 484-RU can be used. The specific number of RUs can be changed similarly to Figure 13 .

[0147] Figure 13 A layout of resource units (RUs) for an 80 MHz PPDU is exemplified. The layout of resource units (RUs) used in the present disclosure can vary. For example, the layout of resource units (RUs) used in an 80 MHz band can vary.

[0148] Figure 13 Operations related to UL-MU are shown. As shown, a transmitting STA (e.g., an AP) can obtain a TXOP 1025 and transmit a trigger frame 1030 by performing channel access through contention (i.e., backoff operation). That is, the transmitting STA (e.g., an AP) can transmit a PPDU including the trigger frame 1030. When the PPDU including the trigger frame is received, a trigger-based (TB) PPDU is transmitted after a delay of SIFS.

[0149] TB PPDUs 1041, 1042 can be transmitted simultaneously and from a plurality of STAs (e.g., user STAs) whose AIDs are indicated in the trigger frame 1030. ACK frames 1050 for the TB PPDUs can be implemented in various forms. For example, the ACK frames 1050 for the TB PPDUs can be implemented in the form of block ACK (BA).

[0150] In Figure 13Within the TXOP 1025, the transmission of the trigger frame 1030, the TB PPDUs 1041, 1042, and / or the ACK frame 1050 can be performed.

[0151] Figure 13 An example of channels used / supported / defined within the 2.4 GHz band is illustrated.

[0152] The 2.4 GHz band can also be referred to by other names, such as the “first band.” In addition, the 2.4 GHz band can refer to a frequency range that uses / supports / defines channels having a center frequency adjacent to 2.4 GHz (e.g., channels having a center frequency between 2.4 GHz and 2.5 GHz).

[0153] The 2.4 GHz band can include multiple 20 MHz channels. Each 20 MHz within the 2.4 GHz band can have a number of channel indices (e.g., indices 1-14). For example, a 20 MHz channel allocation can have a center frequency of 2.412 GHz for channel index 1, a center frequency of 2.417 GHz for channel index 2, and a center frequency of (2.407 + 0.005*N) GHz for channel index N. Channel indices can be referred to by various names, such as channel numbers. The specific values of channel indices and center frequencies can change.

[0154] Figure 14 Four channels within the 2.4 GHz band are illustratively shown. The first frequency region 1111 through the fourth frequency region 1140 can each include one channel. For example, the first frequency region 1111 can include channel 1 (a 20 MHz channel with index 1). In this case, the center frequency of channel 1 can be set to 2412 MHz. The second frequency region 1120 can include channel 6. In this case, the center frequency of channel 6 can be set to 2437 MHz. The third frequency region 1130 can include channel 11. In this case, the center frequency of channel 11 can be set to 2462 MHz. The fourth frequency region 1140 can include channel 14. In this case, the center frequency of channel 14 can be set to 2484 MHz.

[0155] Figure 14 An example of channels used / supported / defined within the 5 GHz band is illustrated.

[0156] The 5 GHz band can be referred to by other names, such as the second band / band, and the like. The 5 GHz band can refer to a frequency range that uses / supports / defines channels with center frequencies greater than or equal to 5 GHz and less than 6 GHz (or less than 5.9 GHz). Alternatively, the 5 GHz band can include multiple channels between 4.5 GHz and 5.5 GHz. Figure 14 The specific values shown in the tables can vary.

[0157] The multiple channels within the 5 GHz band include Unlicensed National Information Infrastructure (UNII)-1, UNII-2, UNII-3, and ISM. UNII-1 can be referred to as UNII-low. UNII-2 can include frequency ranges referred to as UNII-mid and UNII-2 extended. UNII-3 can be referred to as UNII-up.

[0158] Multiple channels can be configured within the 5 GHz band, and the bandwidth of each channel can vary, such as 20 MHz, 40 MHz, 80 MHz, or 160 MHz. For example, the 5170 MHz to 5330 MHz frequency range within UNII-1 and UNII-2 can be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency range can be divided into four channels by a 40 MHz band. The 5170 MHz to 5330 MHz frequency range can be divided into two channels by an 80 MHz band. Alternatively, the 5170 MHz to 5330 MHz frequency range can be divided into one channel by a 160 MHz band.

[0159] Figure 14 Examples of channels that are used, supported, and defined within the 6 GHz band are illustrated.

[0160] The 6 GHz band can also be referred to by other names, such as the third band. The 6 GHz band can refer to a frequency range that uses, supports, and defines channels with center frequencies higher than 5.9 GHz. Figure 14 The specific values shown in the tables can vary.

[0161] For example, a 20 MHz channel can be defined starting at 5.940 GHz in Figure 14 Specifically, the left-most channel of the 20 MHz channels in Figure 6 may have an index of 1 (or channel index, channel number, etc.) and can be assigned a center frequency of 5.945 GHz. In other words, the center frequency of the index N channel can be determined as (5.940 + 0.005*N) GHz.

[0162] Thus, Figure 14The indices (or channel numbers) of the 20 MHz channels in the 5 GHz band are 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, which can be 197, 201, 205, 209, 213, 217, 221, 225, 229, 233. Also, according to the above (5.940 + 0.005*N) GHz rule, Figure 14 The indices of the 40 MHz channels in the 5 GHz band 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.

[0163] The structure of the MAC frame and the type / subtype are described below.

[0164] Figure 14 An example of the MAC frame header is shown. As shown, the MAC frame can include a 2 octet frame control field / information, a 2 octet duration field / information, a 6 octet receiver address (RA) field / information, and a 6 octet transmitter address (TA) field / information. As shown in Figure 14 The four fields can be consecutive as shown in Figure 14 The MAC header of the present disclosure can be modified in various ways, a new field can be inserted between the four fields shown, or at least one of the fields shown can be omitted.

[0165] Figure 15 The MAC header shown in the present disclosure can be located at the very beginning of the MAC frame. That is, the MAC frame can include the MAC header as shown in Figure 15 and the MAC body field / information can be consecutive to the MAC header. The MAC header of the present disclosure includes Figure 16 The MAC frame including the MAC header of the present disclosure is inserted / included in the data field of the PPDU (e.g., UHR PPDU) shown in Figure 16

[0166] The MAC frame included in the data field of the PPDU of the present disclosure can be classified into various types. For example, the MAC frame of the present disclosure can be classified into a control frame, a management frame, and a data frame.

[0167] ​For example, the management frames include the association request, the association response, the re-association request, the re-association response, the probe request, the probe response, the beacon, the disassociation, the authentication, and the de-authentication frames / signals defined in the regular WLAN. For the management frames, Figure 16 the value of the type field (B3 and B2) in the is set to 00. Additionally, Figure 16 the value of the subtype field (B7, B6, B5, B4) in the is as follows: association request (0000), association response (0001), re-association request (0010), re-association response (0011), probe request (0100), probe response (0101), beacon (1000), disassociation (1010), authentication (1011), de-authentication (1100).

[0168] For example, the control frames include the trigger beamforming report poll, the NDP announcement (NDPA), the control frame extension, the control encapsulation, the block acknowledgement request (BlockAckReq), the block acknowledgement (BlockAck), the power save poll (PS-Poll), the request to send (RTS), the clear to send (CTS), the acknowledgement (Ack), and the CF end frames / signals defined in the regular WLAN. For the control frames, Figure 16 the value of the type field (B3 and B2) in the is set to 01. Additionally, Figure 17 the value of the subtype field (B7, B6, B5, B4) in the is as follows: trigger (0010), beamforming report poll (0100), NDP announcement (0101), control frame extension (0110), control encapsulation (0111), block acknowledgement request (1000), block acknowledgement (1001), power save poll (1010), request to send (1011), clear to send (1100), acknowledgement (1101), CF end (1110).

[0169] For example, the data frames include the (QoS) data, the (QoS) null, etc. defined in the regular WLAN. For the data frames, Figure 17 the value of the type field (B3 and B2) in the is set to 10.

[0170] Meanwhile, the non-AP MLD / STA can roam between the AP MLDs. The MLD and the roaming are described below.

[0171] Figure 18 The high-level architecture of the AP MLD is exemplified.

[0172] Reference is made to Figure 18An AP MLD can include at least one AP. The MLD can utilize the upper MAC layer / sublayer to control various processes / parameters shared by multiple APs. For example, the MLD can perform / control authentication, association, sequence number (SN) / packet number (PN) allocation, and power-saving buffering of individually addressed frames.

[0173] Therefore, when using the AP MLD function, the MLD-level parameters can be maintained without resetting when a non-AP MLD / STA moves / roams between multiple APs belonging to that AP MLD.

[0174] In this disclosure, a non-AP MLD / STA can roam from a serving / source AP MLD to another AP MLD (i.e., a target AP MLD). Alternatively, a non-AP MLD / STA can roam from at least one AP in a serving / source AP MLD to at least one AP in another AP MLD (i.e., a target AP MLD). In this case, the non-AP MLD / STA can maintain its associated and authenticated status during and after roaming to another AP MLD. Roaming may include establishing a link with at least one AP in the target AP MLD and / or releasing a link with at least one AP in the serving / source AP MLD. For example, a non-AP MLD / STA may release a link with at least one AP in the serving / source AP MLD after establishing a link with at least one AP in the target AP MLD. As another example, a non-AP MLD / STA may first release a link with at least one AP in the serving / source AP MLD and then establish a link with at least one AP in the target AP MLD.

[0175] Deployment of AP MLD for roaming, such as I. Group ID configuration for roaming As shown.

[0176] II. Group ID announcement Example of an AP MLD deployment for roaming.

[0177] Reference Figure 19 Each AP MLD is located in a different location, i.e., non-co-located, while multiple APs belonging to / subordinate to various AP MLDs are located in the same or nearby locations, i.e., co-located. Co-located APs can refer to APs belonging to the same physical device, or even if these APs do not belong to the same physical device, they are logically located close to each other. Essentially, an AP MLD is a logical entity that can be any single physical device or function as an MLD covering subordinate APs, regardless of location, and can apply MLOs. Ultimately, all APs belonging to various AP MLDs can be subordinate to a group-managed AP MLD. For example, Figure 19The AP MLD 1 in the figure can include the first AP, the second AP, and the third AP.

[0178] In the present disclosure, each AP MLD including a plurality of APs affiliated to a group management AP MLD can be included in a roaming group, and roaming can be performed between the AP MLDs included in the roaming group. That is, roaming can be performed between the AP MLDs included in the roaming group, but roaming cannot be performed between the AP MLDs included in the roaming group and the AP MLDs not included in the roaming group. The AP MLDs included in the roaming group can be referred to as group member AP MLDs. For example, Figure 19 The AP MLD 1, the AP MLD 2, and the AP MLD 3 in the figure can be group member AP MLDs.

[0179] When a non-AP MLD / STA moves, it can roam from one AP MLD to another AP MLD. However, roaming is not limited to movement between different AP MLDs. For example, a non-AP MLD / STA can also change an AP within an AP MLD by roaming.

[0180] Meanwhile, a moving non-AP MLD / STA must be able to identify which AP within a group management AP MLD associated with the non-AP MLD / STA should be roamed to, and when roaming is requested, the group management MLD needs to determine whether the previous AP needs to forward data or management information to the new AP according to which new AP the non-AP MLD / STA roams from the previous AP. Therefore, an identification / identifier (ID) for a roaming group and / or a roaming management AP MLD is required. The present disclosure proposes an identification method considering non-co-located APs affiliated to a group management AP MLD.

[0181] The references (names) in the present disclosure can be changed, and the STA can include an AP STA and / or a non-AP STA.

[0182] Figure 19 An example of a method for identification related to roaming performed by a mobile device according to an embodiment of the present disclosure is illustrated. The mobile device can be an MLD including at least one STA.

[0183] Referring to Figure 20 In step S1701, the mobile device can perform an association procedure with a first AP affiliated to a first MLD.

[0184] In step S1703, the mobile device can obtain a group ID of a roaming group including the first MLD.

[0185] In step S1705, the mobile device can transmit a request frame requesting roaming to a second MLD included in the roaming group. The request frame can include the group ID.

[0186] In step S1707, the mobile device can perform roaming to the second MLD based on receiving the response frame including the group ID.

[0187] In various embodiments, performing roaming to the second MLD can include establishing a link with a second AP affiliated with the second MLD and releasing a link with a first AP affiliated with the first MLD.

[0188] In various embodiments, the link with the first AP can be released after the link with the second AP is established during the process of roaming to the second MLD. Alternatively, the link with the first AP can be established after the link with the second AP is released.

[0189] In various embodiments, the mobile device can maintain an association state during and after roaming is performed.

[0190] In various embodiments, the roaming group can include a plurality of MLDs between which roaming can be performed.

[0191] In various embodiments, the group ID can be obtained by receiving a management frame including at least one of a reduced neighbor report (RNR) element or a basic multi-link element. The group ID can be included in at least one of the RNR element or the basic multi-link element.

[0192] In various embodiments, the request frame can be a probe request frame including a probe request multi-link element. The group ID can be included in at least one of a common information (Info) field or a link information field in the probe request multi-link element.

[0193] In various embodiments, the response frame can be a probe response frame including a basic multi-link element. The group ID can be included in at least one of a common information field or a link information field in the basic multi-link element.

[0194] In various embodiments, at least one of the common information field or the link information field can further include a subfield indicating whether the group ID is present.

[0195] In various embodiments, the mobile device can obtain an ID of the second MLD. The group ID and the ID of the second MLD can be obtained by receiving a management frame including at least one of a reduced neighbor report (RNR) element or a basic multi-link element. The group ID and the ID of the second MLD can be included in at least one of the RNR element or the basic multi-link element.

[0196] In various embodiments, the request frame can be a probe request frame including a probe request multi-link element. The group ID and the ID of the second MLD can be included in at least one of a common information field or a link information field in the probe request multi-link element.

[0197] In various embodiments, the response frame can be a probe response frame including a basic multi-link element. The group ID and the ID of the second MLD can be included in at least one of a common information field or a link information field in the basic multi-link element.

[0198] In various embodiments, the group ID can be included in the common information field, and the ID of the second MLD is included in the link information field.

[0199] In various embodiments, at least one of the common information field or the link information field can include a subfield indicating whether the group ID is present, and a subfield indicating whether the ID of the second MLD is present.

[0200] In various embodiments, the subfield indicating whether the group ID is present can be included in the common information field, and the subfield indicating whether the ID of the second MLD is present can be included in the link information field.

[0201] Figure 20 An example of a method performed by an AP for identification related to roaming according to an embodiment of the disclosure is illustrated. The AP can belong to a first MLD.

[0202] Referring to Figure 20 In step S1801, the AP can perform an association procedure with a mobile device.

[0203] In step S1803, the AP can send a group ID of a roaming group of the first MLD to the mobile device.

[0204] In step S1805, the AP can receive a request frame from the mobile device requesting to roam to a second MLD included in the roaming group. The request frame can include the group ID.

[0205] In step S1807, the AP can send a response frame including the group ID to the mobile device to make the mobile device perform roaming to the second MLD.

[0206] A specific implementation of the method for identification related to roaming is described below.

[0207] Figure 20

[0208] (1) ID configuration for roaming within a group managed AP MLD

[0209] In some implementations, a group member AP MLD can be assigned an ID. In this disclosure, a newly defined group member AP MLD ID can be used for a group member AP MLD. In another example, an existing AP MLD ID can be used for a group member AP MLD. This group member AP MLD ID can be unique within the group member AP MLD, or a unique ID can be assigned for the group member AP MLD within the entire group manager AP MLD or the roaming group. This ID can be assigned to the group manager AP MLD to which the group member AP MLD belongs (i.e., the group manager AP MLD to which the AP belonging to the group member AP MLD belongs). In this disclosure, the ID assigned to the group manager AP MLD to which the group member AP MLD belongs can be referred to as a group manager AP MLD ID or a roaming group ID (or a group ID). This group manager AP MLD ID can be unique within the group manager AP MLD, or can be unique within the entire network. By defining the group manager AP MLD ID to distinguish between various group manager AP MLDs, the scalability problem caused by the limited number of links can be solved, and the identification of more APs can be achieved.

[0210] (2) Unique ID configuration within a group member AP MLD within a group manager AP MLD

[0211] In some implementations, the group member AP MLD ID can be unique within the group member AP MLD. The group member AP MLD ID can have a value such as 0, 1, 2, etc. For example, if the bit size of the group member AP MLD ID is 4 bits, the group member AP MLD ID can have a value from 0 to 15. If the bit size of the group member AP MLD ID is 8 bits, the group member AP MLD ID can have a value from 0 to 127 (or 0 to 255). This is one example, and the bit size of the group member AP MLD ID can vary.

[0212] For example, when the group member AP MLD ID is 0, an AP with group member AP MLD ID 0 can be considered to be co-located and / or affiliated with the same group member AP MLD. That is, if a non-AP MLD / STA identifies a certain group member AP MLD ID, it can identify the APs affiliated with the corresponding group member AP MLD as co-located. Additionally, since other APs belonging to the multiple BSSID (e.g., Transmit BSSID (TxBSSID) or Non-Transmit BSSID (NonTxBSSID)) sets to which each AP affiliated with the group member AP MLD belongs also use the same physical resources, the group member AP MLD ID can also be assigned to these APs. However, other APs belonging to the multiple BSSID sets (e.g., Transmit BSSID (TxBSSID) or Non-Transmit BSSID (NonTxBSSID)) to which these APs belong can have different AP MLD IDs (i.e., can be affiliated with different AP MLDs).

[0213] For example, different group member AP MLD IDs (e.g., group member AP MLD IDs with non-zero values) can be mapped to each group member AP MLD, such that each group member AP MLD can be uniquely identified.

[0214] (3) Unique ID configuration within a group managing AP MLD in a network

[0215] In some implementations, the group managing AP MLD ID (or group ID) can be unique within the network. The group managing AP MLD ID can have values such as 0, 1, 2, etc. For example, if the bit size of the group managing AP MLD ID is 4 bits, the group managing AP MLD ID can have values from 0 to 15, and if the bit size of the group managing AP MLD ID is 8 bits, the group managing AP MLD ID can have values from 0 to 127 (or from 0 to 255). The bit size of the group managing AP MLD ID can vary.

[0216] For example, if the group management AP MLD ID (or group ID) is 0, the APs with group management AP MLD ID 0 can be considered as APs that belong to the same group management AP MLD (i.e., APs that belong to the group member AP MLDS included in the roaming group of the same group management AP MLD). That is, when the non-AP MLD / STA identifies the group management AP MLD ID / group ID, these APs can identify that they currently belong to the same group management AP MLD (or belong to the group member AP MLDS included in the same group). In addition, since other APs in the multiple BSSID (e.g., Transmit BSSID (TxBSSID) or Non-Transmit BSSID (NonTxBSSID)) set to which each AP belonging to the group management AP MLD belongs also use the same physical resource, the group management AP MLD ID can also be assigned to these APs. However, the AP MLD ID of the transmit BSSID (TxBSSID) or non-transmit BSSID (NonTxBSSID) AP MLD to which these APs belong can be different.

[0217] For example, different group management AP MLD IDs (e.g., group management AP MLD IDs with non-zero values) can be mapped so that each group management AP MLD can be uniquely identified.

[0218] (4) Configuration of unique ID within a group management AP MLD

[0219] In some implementations, a group member AP MLD ID can be uniquely assigned to a group member AP MLD within the entire group management AP MLD, and / or a group management AP MLD ID can be uniquely assigned to a group management AP MLD within the entire network.

[0220] The group member AP MLD ID can have values of 0, 1, 2, etc. For example, if the bit size of the group member AP MLD ID is 4 bits, the group member AP MLD ID can have values from 0 to 15. If the bit size of the group member AP MLD ID is 8 bits, the group member AP MLD ID can have values from 0 to 127 (or 0 to 255). The bit size of the group member AP MLD ID can vary.

[0221] The group management AP MLD ID can have values of 0, 1, 2, etc. For example, if the group management AP MLD ID has a bit size of 4 bits, the group management AP MLD ID can have values from 0 to 15. If the group management AP MLD ID has a bit size of 8 bits, the group management AP MLD ID can have values from 0 to 127 (or 0 to 255). The bit size of the group management AP MLD ID can vary.

[0222] A-1) Included in the public information field

[0223] In some implementations, when the newly defined group member AP MLD ID is used for the group member AP MLD, each AP in each AP MLD can advertise MLD roaming information (or roaming information) including information indicating whether roaming is enabled, the group management AP MLD ID, and / or the group member AP MLD ID. For example, the MLD roaming information advertised by each AP in each AP MLD can include at least one of the following:

[0224] - MLD roaming enabled: information indicating whether roaming is enabled. This information can be 1-bit indication information.

[0225] - Group management AP MLD ID (or roaming group ID): ID of the group management AP MLD in the network or the roaming group ID. That is, the APs associated with this ID can belong to the same group management AP MLD.

[0226] - Group member AP MLD ID: ID of the group member AP MLD belonging to the group management AP MLD. That is, the APs associated with the corresponding ID can belong to the same group member AP MLD.

[0227] The above-described MLD roaming information can be included in a management (MGMT) frame (e.g., a beacon frame or a probe response frame). For example, the MLD roaming information can be included in an MLD roaming information element (IE) of the beacon frame / probe response frame, or included in a reduced neighbor report (RNR) IE of the beacon frame / probe response frame. When the MLD roaming information is included in the RNR IE, the format of the RNR IE is as shown in 2) Included in the link information field - always present

[0228] A-3) Included in the link information field - not always present A first example showing the format of the RNR IE including the MLD roaming information according to an embodiment of the disclosure is shown.

[0229] Referring to B-1) Included in the public information field ​The MLD roaming information can be included in a target beacon transmit time (TBTT) information field of a RNR IE for each AP. For example, the MLD roaming information can be included in an MLD parameter subfield of the TBTT information field. If the size of the MLD parameter subfield is not sufficient, the size of the MLD parameter subfield can be modified to contain the MLD roaming information.

[0230] However, since modifying the size of the MLD parameter subfield can cause decoding problems for STAs, a new MLD roaming parameter subfield can be defined in the TBTT information field to include the MLD roaming information if the size of the MLD parameter subfield is not sufficient. As shown in B-2) Included in the link information field - always present the MLD roaming parameter subfield can include an MLD roaming enable subfield, a group managing AP MLD ID, and a group member AP MLD ID. In this case, the MLD roaming parameter subfield can not include the MLD roaming enable subfield since the presence of the MLD roaming parameter subfield itself can indicate that MLD roaming is enabled.

[0231] Since the MLD roaming information can be MLD-related information, the MLD roaming information can be included in a basic multi-link IE of a beacon frame / probe response frame.

[0232] In some implementations, when an existing AP MLD ID is used for a group member AP MLD, each AP in each AP MLD can advertise MLD roaming information (or roaming information) including information indicating whether roaming is enabled, a group managing AP MLD ID, and / or a group member AP MLD ID. For example, the MLD roaming information advertised by each AP in each AP MLD can include at least one of the following:

[0233] - MLD roaming enable: information indicating whether roaming is enabled. The information can be 1-bit indication information.

[0234] - Group managing AP MLD ID (or roaming group ID): an ID of a group managing AP MLD or a roaming group ID in the network. That is, the APs associated with the ID can belong to the same group managing AP MLD.

[0235] The above-described MLD roaming information can be included in a management (MGMT) frame (e.g., a beacon frame or a probe response frame). For example, the MLD roaming information can be included in an MLD roaming information element (IE) of the beacon frame / probe response frame or in a reduced neighbor report (RNR) IE of the beacon frame / probe response frame. When the MLD roaming information is included in the RNR IE, the format of the RNR IE is as shown in B-3) Included in the link information field - not always present .

[0236] C-1) Included in the public information field A second example illustrating a format of an RNR IE including MLD roaming information according to an embodiment of the disclosure is described.

[0237] Referring to C-2) Included in the link information field - always present , the MLD roaming information can be included in a target beacon transmit time (TBTT) information field of the RNR IE for each AP. For example, the MLD roaming information can be included in an MLD parameter subfield of the TBTT information field. If the size of the MLD parameter subfield is not sufficient, the size of the MLD parameter subfield can be modified to include the MLD roaming information.

[0238] However, since modifying the size of the MLD parameter subfield can cause decoding problems for STAs, if the size of the MLD parameter subfield is not sufficient, a new MLD roaming parameter subfield can be defined in the TBTT information field to include the MLD roaming information. As C-3) Included in the link information field - not always present shown, the MLD roaming parameter subfield can include an MLD roaming enable subfield and a group managing AP MLD ID. In this case, the presence of the MLD roaming parameter subfield itself can indicate that MLD roaming is enabled, and thus the MLD roaming parameter subfield can not include the MLD roaming enable subfield.

[0239] Since the MLD roaming information can be information related to MLDs, the information can be included in a basic multi-link IE of a beacon frame / probe response frame.

[0240] III, Group ID request / response

[0241] Before roaming, a non-AP MLD / STA can request information about APs within each group member AP MLD (or APs affiliated with each group member AP MLD) to enable roaming between AP MLDs. To request information about APs affiliated with each group member AP MLD, a multi-link probe request / response mechanism for obtaining information of MLOs can be used.

[0242] In the disclosure, a multi-link probe request refers to a probe request frame transmitted by a STA affiliated with a non-AP MLD, which carries a probe request multi-link element to request information about one or more APs affiliated with the AP MLD.

[0243] The probe request multi-link element can include a multi-link control field, a common information field, and / or a link information field. The multi-link control field can include a presence bitmap subfield. The link information field can include a Per-STA profile subelement. The Per-STA profile subelement can have a format as shown in Table 1 below:

[0244] [Table 1]

[0245]

[0246] In Table 1, the STA information field can be omitted. In this case, the STA control field can be adjacent to the STA profile field, and the STA profile field can be placed immediately after the STA control field (or the STA control field can be placed immediately before the STA profile field). In some implementations, if a newly defined group member AP MLD ID is used for the group member AP MLD, the group management AP MLD ID and the group member AP MLD ID can be included in the common information field and / or the link information field of the probe request multi-link element in the following manner:

[0247] D-1) Included in the public information field

[0248] The presence bitmap subfield can indicate whether the common information field includes the group management AP MLD ID and / or the group member AP MLD ID. For example, the presence bitmap subfield can have a format as shown in Table 2 below:

[0249] [Table 2]

[0250]

[0251] In Table 2, the group management AP MLD ID present field can indicate whether the common information field includes the group management AP MLD ID. The group member AP MLD ID present field can indicate whether the common information field includes the group member AP MLD ID. When the group management AP MLD ID and the group member AP MLD ID are included in the common information field, the common information field can have a format as shown in Table 3 below:

[0252] [Table 3]

[0253]

[0254] If the group management AP MLD ID and the group member AP MLD ID are included in the common information field, the multi-link probe request can request information of only APs affiliated to the same group management AP MLD ID and the same group member AP MLD ID. In other words, information of APs affiliated to the same group management AP MLD but having different group member AP MLD IDs can not be requested. A- D-2) Included in the link information field - always present

[0255] The group management AP MLD ID and the group member AP MLD ID can always exist in the link information field. In this case, the link information field can not include the group management AP MLD ID presence field and the group member AP MLD ID presence field.

[0256] The link information field can include a plurality of Per-STA profile sub-elements, and a format of each Per-STA profile sub-element is as shown in above. The group management AP MLD ID and the group member AP MLD ID can be included in a STA control field of the Per-STA profile sub-element, as shown in below:

[0257] [Table 4]

[0258]

[0259] Each link ID can indicate a request for a corresponding AP. The group member AP MLD ID in the STA control field of the Per-STA profile sub-element can indicate a group member AP MLD. If the group management AP MLD ID and the group member AP MLD ID are included in the link information field, information about APs affiliated to a plurality of group member AP MLD IDs can be requested. However, when requesting information about APs affiliated to the same group member AP MLD, including the group management AP MLD ID and the group member AP MLD ID in the link information field can cause greater overhead than including them in the common information field. D-3) Included in the link information field - not always present

[0260] The group management AP MLD ID and the group member AP MLD ID can not always exist in the link information field. In this case, the link information field can include the group management AP MLD ID presence field and the group member AP MLD ID presence field.

[0261] For example, the group management AP MLD ID present field and the group member AP MLD ID present field can be included in the STA control field of the Per-STA profile subelement. The group management AP MLD ID present field can indicate whether the link information field includes the group management AP MLD ID of the AP corresponding to the link ID. The group member AP MLD ID present field can indicate whether the link information field includes the group member AP MLD ID of the AP corresponding to the link ID. In this case, the group management AP MLD ID and / or the group member AP MLD ID can be included in the STA information field or the STA profile field. When the group management AP MLD ID and the group member AP MLD ID are included in the link information field, information about the AP belonging to a plurality of group member AP MLD IDs can be requested.

[0262] For example, when information about the AP belonging to the same group member AP MLD is requested, the group member AP MLD ID can be included in the common information field, not in the link information field. Accordingly, the present case can reduce overhead as compared to the case in which the group member AP MLD ID must be included in the link information field.

[0263] For example, if the common information field includes the group management AP MLD ID and the group member AP MLD ID, this can mean that information about the AP corresponding to the same group member AP MLD ID is being requested. In this case, the link information field can not include the group management AP MLD ID and the group member AP MLD ID. Accordingly, the link information field can not include the group management AP MLD ID present field and the group member AP MLD ID present field.

[0264] In some implementations, if an existing AP MLD ID is used for the group member AP MLD, the group management AP MLD ID can be included in the common information field and / or the link information field of the probe request multi-link element as follows:

[0265] Figure 21

[0266] The presence bitmap subfield can indicate whether the common information field includes the group management AP MLD ID. For example, the presence bitmap subfield can have a format as shown in Table 5 below:

[0267] [Table 5]

[0268]

[0269] In Table 5, the Group Management AP MLD ID presence field indicates whether the Public Information field includes the Group Management AP MLD ID. If the Group Management AP MLD ID is included in the Public Information field, the Public Information field can have a similar format as shown in Table 6 below:

[0270] [Table 6]

[0271]

[0272] If the group management AP MLD ID is included in the public information field, a multi-link probe request can only request information from APs belonging to the same group management AP MLD ID and the same AP MLD ID in the same group. In other words, information from APs belonging to the same group management AP MLD but with different AP MLD IDs may not be requested. Figure 21 IV. Use of group ID in DS-STA-NOTIFY

[0273] The group management AP MLD ID can always be present in the link information field. In this case, the link information field may not include the group management AP MLD ID presence field.

[0274] The link information field can include multiple Per-STA profile sub-elements, and the format of each Per-STA profile sub-element is shown in Table 1 above. The group management AP MLD ID can be included in the STA control field of the Per-STA profile sub-element, as shown in Table 7 below:

[0275] [Table 7]

[0276]

[0277] Each link ID can be used to indicate a request to the corresponding AP. The AP MLD ID included in the multi-link element of the probe request, and the group management AP MLD ID in the STA control field of the Per-STA profile sub-element, can indicate the group member AP MLD. If the group management AP MLD ID is included in the link information field, information about APs belonging to multiple AP MLD IDs can be requested. However, when requesting information about APs belonging to the same group member AP MLD, including the group management AP MLD ID in the link information field may incur greater overhead than including it in the common information field. Figure 16

[0278] The group management AP MLD ID can not always exist in the link information field. In this case, the link information field can include a group management AP MLD ID presence field.

[0279] For example, the group management AP MLD ID presence field can be included in the STA control field of the Per-STA profile subelement. The group management AP MLD ID presence field can indicate whether the link information field includes the group management AP MLD ID of the AP corresponding to the link ID. In this case, the group management AP MLD ID can be included in the STA information field or the STA profile field. If the group management AP MLD ID is included in the link information field, information about the AP belonging to multiple AP MLD IDs can be requested.

[0280] For example, when information about the AP belonging to the same AP MLD ID is requested, the group management AP MLD ID can be included in the common information field, not in the link information field. Accordingly, the present case can reduce overhead as compared to the case where the group management AP MLD ID must be included in the link information field.

[0281] For example, if the common information field includes the group management AP MLD ID, this can mean that information about the AP corresponding to the same AP MLD ID is being requested. In this case, the link information field can not include the group management AP MLD ID. Accordingly, the link information field can also not include the group management AP MLD ID presence field.

[0282] In the present disclosure, a multi-link probe response refers to a probe response frame transmitted by an AP belonging to an AP MLD, which carries a basic multi-link element in response to a multi-link probe request, thereby providing a complete profile or requested information for one or more APs belonging to the AP MLD.

[0283] The basic multi-link element can include a multi-link control field, a common information field, and / or a link information field. The multi-link control field can include a presence bitmap subfield. The link information field can include a Per-STA profile subelement. The Per-STA profile subelement can have a format as shown in Table 8 below.

[0284] [Table 8]

[0285]

[0286] In , the STA info field can be omitted. In this case, the STA control field can be adjacent to the STA profile field, and the STA profile field can be placed immediately after the STA control field (or, the STA control field can be placed immediately before the STA profile field). In some implementations, if the newly defined group member AP MLD ID is used for the group member AP MLD, the group management AP MLD ID and the group member AP MLD ID can be included in the public information field and / or the link information field of the basic multi-link element as follows:

[0287] Figure 16

[0288] The present method can be applied when the multi-link probe request including the group management AP MLD ID and the group member AP MLD ID is transmitted according to the method described in the above "A-1) Included in the public information field".

[0289] According to the present method, the presence bitmap subfield of the basic multi-link element can include a group management AP MLD ID presence field and a group member AP MLD ID presence field. The group management AP MLD ID presence field can indicate whether the public information field includes the group management AP MLD ID. The group member AP MLD ID presence field can indicate whether the public information field includes the group member AP MLD ID. Accordingly, the group management AP MLD ID and the group member AP MLD ID can be included in the public information field. If the group management AP MLD ID and the group member AP MLD ID are included in the public information field, the corresponding multi-link probe response can only provide information about APs belonging to the same group member AP MLD.

[0290] Figure 1

[0291] The present method can be applied when the multi-link probe request including the group management AP MLD ID and the group member AP MLD ID is transmitted according to the method described in the above "A-2) Included in the link information field - always present".

[0292] According to the present method, the group management AP MLD ID and the group member AP MLD ID of the AP corresponding to the link ID of each Per-STA profile sub-element can be included in the STA control field of the corresponding Per-STA profile sub-element. When the group management AP MLD ID and the group member AP MLD ID are included in the link information field, information about the APs belonging to the multiple group member AP MLD IDs can be provided. However, in providing information about the APs belonging to the same group member AP MLD, including the group management AP MLD ID and the group member AP MLD ID in the link information field can cause greater overhead than including them in the common information field.

[0293] Figure 5

[0294] The present method can be applied when transmitting multiple link probe requests including the group management AP MLD ID and the group member AP MLD ID according to the method described in the above "A-3) Included in the link information field - Non-always present".

[0295] According to the present method, the group management AP MLD ID present field and the group member AP MLD ID present field can be included in the STA control field of the Per-STA profile sub-element. The group management AP MLD ID present field can indicate whether the link information field includes the group management AP MLD ID of the AP corresponding to the link ID. The group member AP MLD ID present field can indicate whether the link information field includes the group member AP MLD ID of the AP corresponding to the link ID. In this case, the group management AP MLD ID and / or the group member AP MLD ID can be included in the STA information field or the STA profile field. When the group management AP MLD ID and the group member AP MLD ID are included in the link information field, information about the APs belonging to the multiple group member AP MLD IDs can be provided.

[0296] For example, in providing information about the APs belonging to the same group member AP MLD, the group member AP MLD ID can be included in the common information field without being included in the link information field. Accordingly, the present case can reduce overhead compared to the case where the link information field must include the group member AP MLD ID.

[0297] For example, if the group member AP MLD ID is unique within the group member AP MLD, the group member AP MLD ID can be omitted when it is 0. This means that an AP receiving a multi-link probe request that does not carry a group member AP MLD ID can implicitly identify that the request is for information about other APs in the same group member AP MLD as itself.

[0298] For example, if the common information field includes a group management AP MLD ID and a group member AP MLD ID, this can mean that information of an AP corresponding to the same group member AP MLD ID is being requested. In this case, the link information field can not include a group management AP MLD ID and a group member AP MLD ID. Accordingly, the link information field can not include a group management AP MLD ID present field and a group member AP MLD ID present field.

[0299] In some implementations, if an existing AP MLD ID is used for a group member AP MLD, the group management AP MLD ID can be included in the common information field and / or the link information field of the basic multi-link element as follows:

[0300] Figure 1

[0301] This method can be applied when a multi-link probe request including a group management AP MLD ID is transmitted according to the method of the above "C-1) included in the common information field".

[0302] According to this method, the presence bitmap subfield of the basic multi-link element can include a group management AP MLD ID present field. The group management AP MLD ID present field can indicate whether the common information field includes a group management AP MLD ID. Accordingly, the group management AP MLD ID can be included in the common information field. If the group management AP MLD ID is included in the common information field, the multi-link probe response can only provide information of APs belonging to the same group member AP MLD ID and the same group management AP MLD ID.

[0303] Figure 5

[0304] This method can be applied when a multi-link probe request including a group management AP MLD ID is transmitted according to the method of the above "C-2) included in the link information field - always present".

[0305] According to the present method, the group managing AP MLD ID of the AP corresponding to the link ID of each Per-STA profile sub-element can be included in the STA control field of the corresponding Per-STA profile sub-element. If the group managing AP MLD ID is included in the link information field, information about the APs belonging to multiple AP MLD IDs can be provided. However, in providing information about the APs belonging to the same AP MLD ID, including the group managing AP MLD ID in the link information field can result in greater overhead than including it in the common information field.

[0306] Figure 1

[0307] The present method can be applied when transmitting a multi-link probe request including a group managing AP MLD ID in the method described in the above "C-3) Included in the link information field - not always present".

[0308] According to the present method, a group managing AP MLD ID present field can be included in the STA control field of the Per-STA profile sub-element. The group managing AP MLD ID present field can indicate whether the link information field includes the group managing AP MLD ID of the AP corresponding to the link ID. In this case, the group managing AP MLD ID can be included in the STA information field or the STA profile field. If the group managing AP MLD ID is included in the link information field, information about the APs belonging to multiple AP MLD IDs can be provided.

[0309] For example, in providing information about the APs belonging to the same AP MLD ID, the group managing AP MLD ID can be included in the common information field without being included in the link information field. Thus, the present case can reduce overhead compared to the case where the group managing AP MLD ID must be included in the link information field.

[0310] For example, if the group managing MLD ID is unique within the network, the group managing AP MLD ID can be omitted when it is 0. That is, the AP receiving the multi-link probe request carrying no group managing AP MLD ID can implicitly recognize that the request is a request for information about other group member AP MLDs belonging to its own group managing AP MLD and / or information about the APs belonging to the group member AP MLDs.

[0311] For example, if the public information field includes the group management AP MLD ID, this can mean that information about APs corresponding to the same group management AP MLD ID is being requested, in which case the link information field can not include the group management AP MLD ID. Correspondingly, the link information field can also not include the group management AP MLD ID present field.

[0312] Figure 1 Examples of group management AP MLD ID and / or group member AP MLD ID based multi-link probe request / response according to embodiments of the disclosure are illustrated.

[0313] Referring to Figure 5 , the MLD / STA can request information about AP 1 and AP 4 via a multi-link probe request to AP 3 belonging to the group member AP MLD 1. Since the multi-link probe request includes the group management AP MLD ID 0 and the group member AP MLD ID 0 for AP 1, and the group management AP MLD ID 0 and the group member AP MLD ID 1 for AP 4, the multi-link probe request is a request for information about APs belonging to other group member AP MLDs that belong to the same group management AP MLD. Therefore:

[0314] - For method A-1 / A-3, the group member MLD ID can not be present in the public information field of the multi-link probe request frame. In addition, the Per-STA profile sub-element for AP 1 can include the group member AP MLD ID 0, and the Per-STA profile sub-element for AP 4 can include the group member AP MLD ID 1.

[0315] - For method B-1 / B-3, the group management AP MLD ID can not be present in the public information field of the multi-link probe request frame.

[0316] Although the link ID of AP 1 and the link ID of AP 4 are both 0, the (group management AP MLD ID, group member AP MLD ID) combination of the corresponding APs is different (i.e., group management AP MLD ID 0 and group member AP MLD ID 0 for AP 1, and group management AP MLD ID 0 and group member AP MLD ID 1 for AP 4), so AP 1 and AP 4 can be distinguished by the group management AP MLD ID and / or the group member AP MLD ID.

[0317] Similarly, AP 3 can provide information about AP 1 and AP 4 via a multi-link probe response. In this case:

[0318] - For Method C-1 / C-3, the group member AP MLD ID can not be present in the public information field of the multi-link probe response frame. In addition, the Per-STA Profile sub-element for AP 1 can include group member AP MLD ID 0, and the Per-STA Profile sub-element for AP 4 can include group member AP MLD ID 1.

[0319] - For Method D-1 / D-3, the group owner AP MLD ID can not be present in the public information field of the multi-link probe response frame.

[0320] Figure 1

[0321] While the MLD / STA roams from group member AP MLD 1 to group member AP MLD 2, the MLD / STA can receive data frames from at least one AP in the currently associated group member AP MLD 1. That is, before the MLD / STA is associated with the group member AP MLD 2, the APs in the group member AP MLD 2 do not transmit data frames. If all group member AP MLDs within the AP MLD domain receive data frames for their respective MLD / STAs from a distribution system (DS), then the APs in the group member AP MLD 2 can transmit data frames even before the MLD / STA is associated with the group member AP MLD 2. However, it can be inefficient for all group member AP MLDs within the AP MLD domain to receive data frames for their respective MLD / STAs from the DS. Therefore, it can be considered to allow the MLD / STA to receive data frames from the APs in the group member AP MLD 1 until the roaming is triggered. Therefore, if the roaming is triggered, a method of receiving data frames from the APs in the group member AP MLD 2 (target group member APs performing the roaming) is needed.

[0322] The DS can map which STAs are associated with which group member AP MLDs through DS-STA-NOTIFY.request from the group owner AP MLD. This enables the DS to forward data to the group member AP MLDs with which the MLD / STAs are associated. shows the primitive parameters of DS-STA-NOTIFY.request.

[0323] [Table 9]

[0324]

[0325] Therefore, to send data to each AP in a group member AP MLD located in multiple locations within the group management AP MLD, the group member AP MLD ID (or AP MLD ID) can be added to the primitive parameter of DS-STA-NOTIFY.request. That is, data from the MLD / STA can be sent from the DS only to the APs in the group member AP MLD that are mapped to the group member AP MLD ID (or AP MLD ID). In various implementations, the primitive parameter of DS-STA-NOTIFY.request can be configured as follows:

[0326] - Add a list of group member AP MLD IDs (or AP MLD IDs) as an additional parameter: DS can send data to APs in the group member AP MLD that correspond to the listed group member AP MLD IDs (or AP MLD IDs).

[0327] - New temporary DS-STA-NOTIFY.request configuration: Adds a new temporary DS-STA-NOTIFY.request to allow the MLD / STA to temporarily receive data from the DS before being associated with the AP of the target group member AP MLD performing the roaming. DS-STA-NOTIFY.request and temporary DS-STA-NOTIFY.request can be configured by adding the group member AP MLD ID (or AP MLD ID) to the existing primitive parameters.

[0328] To update this mapping, MLD / STA can send a notification to the group member AP MLD's AP (e.g., before roaming) before the roaming process. Figure 5 The AP of group member AP MLD 1 and / or the AP of target group member AP MLD that the STA wants to roam to (e.g., Figure 1 The AP in group member AP MLD 2 sends a request including at least one of the following:

[0329] - Attached DS-STA-NOTIFY instruction: Requests data to be sent via DS to the target group member APMLD to which the STA is to roam.

[0330] - Group Member AP MLD ID (or AP MLD ID): Indicates the group member AP MLD ID (or AP MLD ID) for which DS-STA-NOTIFY will be updated. One or more group member AP MLD IDs (or AP MLD IDs) may be indicated.

[0331] The above information can be sent in the management frame / management action frame.

[0332] Various embodiments of this disclosure can also be applied to EHT / UHR. For example, the group management AP MLD can be a UHR AP MLD, and the group member AP MLD can be an EHT AP MLD. Accordingly, the group management AP MLD ID can be a UHR AP MLD ID, and the group member AP MLD ID can be an EHT AP MLD ID.

[0333] The technical features described above in this disclosure can be applied to various apparatuses and methods. For example, the technical features described above in this disclosure can be derived from... Figure 1 and / or Figure 5 The device executes / supports this. For example, the technical features described above in this disclosure can be applied only to... Figure 1 and / or Figure 5 Part of it. For example, the technical features described above in this disclosure can be based on Figure 1 Implemented using processing chips 114 and 124, or based on Figure 1 Implemented by processors 111 and 121 and memories 112 and 122, or based on ​ This is achieved through a processor 510 and a memory 520.

[0334] For example, ​ The processor 111, the processing chip 114 and / or ​ The processor 510 can be configured to execute instructions stored in the memories 112 and 520 to implement the method performed by the mobile device in this disclosure. The method includes: performing an association process with a first access point (AP) belonging to a first multilink device (MLD); obtaining a group identifier (ID) of a roaming group including the first MLD; sending a roaming request frame including the group ID to a second MLD included in the roaming group; and performing roaming to the second MLD based on receiving a response frame including the group ID.

[0335] For example, ​ The processor 121 and / or processing chip 124 may be configured to execute instructions stored in memory 122 to implement the method performed by the AP belonging to the first MLD in this disclosure. The method includes: performing an association process with a mobile device; sending a group identifier (ID) of a roaming group including the first MLD to the mobile device; receiving from the mobile device a request frame requesting roaming to a second MLD included in the roaming group, the request frame including the group ID; and sending a response frame including the group ID to the mobile device to cause the mobile device to perform roaming to the second MLD.

[0336] The technical features of this disclosure can be implemented based on a computer-readable medium (CRM) (e.g., a non-transitory CRM). For example, the CRM in this disclosure may include at least one CRM storing program code that implements instructions executable by at least one processor.

[0337] For example, the CRM could be ​ memory 112, ​ The CRM may store instructions, which are processed by a processor (e.g., ...). ​ The processor 111, the processing chip 114 and / or ​ When executed by the processor 510, the method performed by the mobile device of the present disclosure is implemented. The method includes: performing an association process with a first access point (AP) belonging to a first multilink device (MLD); obtaining a group identifier (ID) of a roaming group including the first MLD; sending a roaming request frame including the group ID to a second MLD included in the roaming group; and performing roaming to the second MLD based on receiving a response frame including the group ID.

[0338] For example, the CRM could be ​ The CRM may store instructions, which are processed by a processor (e.g., ...). ​ When executed by the processor 121 and / or processing chip 124, the method performed by the AP belonging to the MLD in this disclosure is implemented. The method includes: performing an association process with a mobile device; sending a group identifier (ID) of a roaming group including a first MLD to the mobile device; receiving from the mobile device a request frame requesting roaming to a second MLD included in the roaming group, the request frame including the group ID; and sending a response frame including the group ID to the mobile device to cause the mobile device to perform roaming to the second MLD.

[0339] The aforementioned technical features of this disclosure are applicable to various applications or business models. For example, the aforementioned technical features can be applied to wireless communication in devices that support artificial intelligence (AI).

[0340] Artificial intelligence (AI) refers to the field of research concerning artificial intelligence or the methods used to create it, while machine learning refers to the field of research concerning methods for defining and solving various problems within the field of AI. Machine learning is also defined as an algorithm that improves operational performance through stable operational experience.

[0341] An artificial neural network (ANN) is a model used in machine learning, and can refer to a model that solves a problem as a whole, including artificial neurons (nodes) that form a network by combining synapses. An artificial neural network can be defined by a connection pattern between neurons of different layers, a learning process that updates model parameters, and an activation function that generates an output value.

[0342] An artificial neural network can include an input layer, an output layer, and optionally one or more hidden layers. Each layer includes one or more neurons, and an artificial neural network can include synapses that connect neurons. In an artificial neural network, each neuron can output a function value of an activation function of an input signal input through a synapse, a weight, and a bias.

[0343] A model parameter refers to a parameter determined through learning, and includes a weight of a synapse connection and a bias of a neuron. A hyperparameter refers to a parameter to be set before learning in a machine learning algorithm, and includes a learning rate, a number of iterations, a minimum batch size, and an initialization function.

[0344] Learning an artificial neural network can aim to determine model parameters for minimizing a loss function. The loss function can be used as an index for determining optimal model parameters in the process of learning an artificial neural network.

[0345] Machine learning can be divided into supervised learning, unsupervised learning, and reinforcement learning.

[0346] Supervised learning refers to a method of training an artificial neural network using a label given to training data, in which the label can indicate a 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 can refer to a method of training an artificial neural network without a label given to training data. Reinforcement learning can refer to a training method for training an agent defined in an environment to select an action or a sequence of actions to maximize a cumulative reward at each state.

[0347] Machine learning implemented using a deep neural network (DNN) including a plurality of hidden layers among artificial neural networks is referred to as deep learning, and deep learning is a part of machine learning. Hereinafter, machine learning is explained to include deep learning.

[0348] The foregoing technical features can be applied to wireless communication of a robot.

[0349] A robot can refer to a machine that automatically processes or operates a given task using its own ability. In particular, a robot having a function of recognizing an environment and autonomously making a judgment to perform an operation can be referred to as an intelligent robot.

[0350] Robots can be classified into industrial, medical, home, military robots, etc. according to use or field. The robots can include actuators or drivers including motors to perform various physical operations such as moving robot joints. In addition, the movable robots can include wheels, brakes, propellers, etc. in the drivers to travel on the ground or fly in the air by the drivers.

[0351] The foregoing technical features can be applied to a device supporting extended reality.

[0352] Extended reality is collectively referred to as virtual reality (VR), augmented reality (AR), and mixed reality (MR). The VR technology is a computer graphics technology that provides only real-world objects and backgrounds in CG images, the AR technology is a computer graphics technology that provides virtual CG images on real object images, and the MR technology is a computer graphics technology that provides virtual objects mixed and combined with the real world.

[0353] The MR technology is similar to the AR technology in that real objects and virtual objects can be displayed together. However, in the AR technology, virtual objects are used as a supplement to real objects, whereas in the MR technology, virtual objects and real objects are used as equal states.

[0354] The XR technology can be applied to a head-mounted display (HMD), a head-up display (HUD), a mobile phone, a tablet, a laptop computer, a desktop computer, a television, a digital signage, etc. A device to which the XR technology is applied can be referred to as an XR device.

[0355] The present disclosure can have various advantageous effects.

[0356] For example, when a non-AP MLD roams, it can check whether a target AP MLD is included in the same roaming group as an AP MLD with which the non-AP MLD has currently established a link, and can increase the number of APs capable of performing roaming.

[0357] The advantageous effects that can be obtained through the specific embodiments of the present disclosure are not limited to the advantageous effects listed above. For example, there can be various technical effects that can be understood and / or derived by one of ordinary skill in the art from the present disclosure. Therefore, the specific effects of the present disclosure are not limited to those explicitly described herein, but can include various effects that can be understood or derived from the technical features of the present disclosure.

[0358] The claims in this disclosure can be combined in various ways. For example, the technical features in the method claims of this disclosure can be combined to be implemented or performed in an apparatus, and the technical features in the apparatus claims can be combined to be implemented or performed in a method. Furthermore, the technical features in the method claims and the apparatus claims can be combined to be implemented or performed in an apparatus, and the technical features in the method claims and the apparatus claims can be combined to be implemented or performed in a method.

Claims

1. A method performed by a mobile device in a wireless local area network (LAN) system, the method comprising: Perform the association process with the first access point (AP) belonging to the first multi-link device (MLD); Obtain the group identifier (ID) of the roaming group that includes the first MLD; Send a roaming request frame to a second MLD included in the roaming group, the request frame including the group ID; and Based on the received response frame including the group ID, a roaming to the second MLD is performed.

2. The method according to claim 1, wherein, Performing the roaming to the second MLD includes: Establish a link with the second AP belonging to the second MLD; and Release the link with the first AP belonging to the first MLD.

3. The method according to claim 2, wherein, After establishing a link with the second AP, the link with the first AP is released.

4. The method according to claim 1, wherein, The mobile device maintains its associated state during and after the roaming is performed.

5. The method according to claim 1, wherein, The roaming group includes multiple MLDs, and roaming can be performed between the multiple MLDs.

6. The method according to claim 1, wherein, The group ID is obtained by receiving a management frame, the management frame including at least one of a Reduced Neighbor Report (RNR) element or a Basic Multilink element, and The group ID is included in at least one of the RNR element or the basic multilink element.

7. The method according to claim 1, wherein, The request frame is a probe request frame that includes probe request multi-link elements, and The group ID is included in at least one of the public information field or the link information field in the multi-link element of the probe request.

8. The method according to claim 1, wherein, The response frame is a probe response frame that includes basic multi-link elements, and The group ID is included in at least one of the public information field or the link information field in the basic multi-link element.

9. The method according to claim 7 or 8, wherein, At least one of the public information field or the link information field further includes a subfield indicating whether the group ID exists.

10. The method of claim 1, further comprising obtaining the ID of the second MLD. in, The group ID and the ID of the second MLD are obtained by receiving a management frame that includes at least one of a Reduced Neighbor Report (RNR) element or a Basic Multilink element, and The group ID and the ID of the second MLD are included in at least one of the RNR element or the basic multilink element.

11. The method according to claim 1, wherein, The request frame is a probe request frame that includes probe request multi-link elements, and The group ID and the ID of the second MLD are included in at least one of the public information field or the link information field in the probe request multi-link element.

12. The method according to claim 1, wherein, The response frame is a probe response frame that includes basic multi-link elements, and The group ID and the ID of the second MLD are included in at least one of the public information field or the link information field in the basic multi-link element.

13. The method according to claim 11 or 12, wherein, The group ID is included in the public information field, and the ID of the second MLD is included in the link information field.

14. The method according to claim 11 or 12, wherein, At least one of the public information field or the link information field includes a subfield indicating whether the group ID exists and a subfield indicating whether the ID of the second MLD exists.

15. The method according to claim 14, wherein, The subfield indicating whether the group ID exists is included in the public information field, and the subfield indicating whether the ID of the second MLD exists is included in the link information field.

16. A mobile device in a wireless local area network (LAN) system, the mobile device comprising: transceiver; Memory; as well as At least one processor, operatively coupled to the transceiver and the memory, The memory stores instructions that perform operations based on execution by the at least one processor, the operations including: Perform the association process with the first access point (AP) belonging to the first multi-link device (MLD); Obtain the group identifier (ID) of the roaming group that includes the first MLD; Send a roaming request frame to a second MLD included in the roaming group, the request frame including the group ID; and Based on the received response frame including the group ID, a roaming to the second MLD is performed.

17. A device configured to operate in a wireless local area network (LAN) system, the device comprising: At least one processor; as well as At least one memory operatively coupled to the at least one processor, wherein the at least one memory stores instructions that perform operations based on execution by the at least one processor, the operations including: Perform the association process with the first access point (AP) belonging to the first multi-link device (MLD); Obtain the group identifier (ID) of the roaming group that includes the first MLD; Send a roaming request frame to a second MLD included in the roaming group, the request frame including the group ID; and Based on the received response frame including the group ID, a roaming to the second MLD is performed.

18. A non-transitory computer-readable medium (CRM) storing program code implementing instructions that perform operations based on execution by at least one processor, the operations including: Perform the association process with the first access point (AP) belonging to the first multi-link device (MLD); Obtain the group identifier (ID) of the roaming group that includes the first MLD; Send a roaming request frame to a second MLD included in the roaming group, the request frame including the group ID; and Based on the received response frame including the group ID, a roaming to the second MLD is performed.

19. A method performed by a first access point (AP) belonging to a first multilink device (MLD) in a wireless local area network (LAN) system, the method comprising: Perform the association process with the mobile device; Send the group identifier (ID) of the roaming group, including the first MLD, to the mobile device; The mobile device receives a request frame requesting roaming to a second MLD included in the roaming group, the request frame including the group ID; and A response frame including the group ID is sent to the mobile device so that the mobile device can perform roaming to the second MLD.

20. A first access point (AP) belonging to a first multi-link device (MLD) in a wireless local area network (LAN) system, the first AP comprising: transceiver; Memory; as well as At least one processor, operatively coupled to the transceiver and the memory, The memory stores instructions that perform operations based on execution by the at least one processor, the operations including: Perform the association process with the mobile device; Send the group identifier (ID) of the roaming group, including the first MLD, to the mobile device; The mobile device receives a request frame requesting roaming to a second MLD included in the roaming group, the request frame including the group ID; and A response frame including the group ID is sent to the mobile device so that the mobile device can perform roaming to the second MLD.

Images