WO2020040589A1 - Method and device for configuring links for executing communication in wireless lan system - Google Patents

Abstract

The method executed in a wireless local area network (WLAN) system, according to various embodiments, may comprise: a step in which an STA, which supports a first link and a second link, carries out a discovery process via the first link; a step in which the STA carries out a discovery process via the second link; a step in which the STA carries out a process for association with an access point (AP) via the first link; a step in which the STA transmits information about the second link to the AP via the first link; and a step in which the STA carries out a second communication with the AP via the second link.

Description

Method and apparatus for establishing a link for performing communication in a WLAN system

The present disclosure relates to a technique for transmitting and receiving data in wireless communication, and more particularly, to a method and apparatus for establishing a link for performing communication in a wireless LAN system.

Wireless network technologies may include various types of wireless local area networks (WLANs). WLANs can be used to interconnect nearby devices together employing widely used networking protocols. The various technical features described herein may be applied to any communication standard, such as WiFi or, more generally, any of the IEEE 802.11 wireless protocol families.

In wireless local area networks (WLANs), methods for connection between STAs have been improved in various ways. In detail, the STA may perform a discovery process, an association process, and the like, to connect with the AP. Through the discovery process or the association process, the STA may exchange information necessary for connection with the AP.

This specification proposes technical features that can be used to improve existing standards or to be used in new communication standards. Specifically, the STA may transmit and receive various information to establish a connection with the AP. The STA may establish a connection for transmitting and receiving data with the AP based on the various information.

It is common for an STA (Station) based on the existing IEEE 802.11 standard to use one channel for transmitting one packet or frame. Therefore, the existing STA did not need to transmit a signal through a plurality of channels. Starting with the IEEE 802.11be standard, multi-link may be supported.

However, when the STA according to the existing IEEE 802.11 standard is connected to an AP supporting multi-link, it is necessary to determine a link for transmitting and receiving data among the links supported by the AP, and perform communication with a link for transmitting and receiving data. . Accordingly, the STA needs to transmit information for determining a link for transmitting and receiving data to the AP. Therefore, an operation for determining a link for transmitting and receiving data at the STA or the AP may be required.

In addition, even when the STA supporting the multi-link and the STA supporting the multi-link are connected, an operation of the STA or the AP for performing communication through the multi-link may be required.

An example according to the present disclosure relates to a method and apparatus for establishing a link for performing communication. In detail, in the STA, a method for transmitting information about the second link to the AP through the first link and performing communication with the AP through the second link may be required.

In a method performed in a wireless local area network (WLAN) according to various embodiments of the present disclosure, an STA supporting a first link and a second link may perform a discovery process through the first link. Step, by the STA, performing a discovery process, through the second link, the STA, through the first link, performing an association process with an access point (AP), the STA , Transmitting information regarding the second link to the AP through the first link, and performing, by the STA, a second communication with the AP through the second link. .

According to an example according to the present specification, STAs supporting the first link and the second link may transmit information about the second link to the AP via the first link. Specifically, the STA may transmit quality information (eg, a Receive Signal Strength Indicator (RSSI) or a Signal to Interference plus Noise Ratio (SINR) to the AP regarding the second link. Based on the information about the communication, the communication may be performed through the second link, and in the STA according to an example of the present specification, information about the second link is transmitted through the first link, and the AP and the second link are transmitted. The method of performing communication through may enable efficient signal transmission and reduce unnecessary power consumption.

1 is a conceptual diagram of a layer architecture of a WLAN system supported by IEEE 802.11.

2 shows an example of a WLAN system.

3 is a diagram illustrating a frequency domain used in a WLAN system.

4 illustrates an example of network discovery / discovery.

5 shows an example of a PPDU transmitted and received by an STA of the present specification.

6 shows an example of a PPDU according to a conventional WLAN standard.

7 shows another example of a PPDU according to a conventional WLAN standard.

8 is a diagram illustrating another example of the HE-PPDU.

9 is a diagram illustrating an arrangement of resource units (RUs) used on a 20 MHz band.

10 is a diagram illustrating an arrangement of resource units (RUs) used on a 40 MHz band.

11 is a diagram illustrating an arrangement of resource units (RUs) used on an 80 MHz band.

12 shows an example of UL MU communication.

13 shows an example of a trigger frame.

14 shows an example of a common information field.

15 shows an example of a subfield included in a per user information field.

FIG. 16 is a diagram illustrating a method of performing UORA in a WLAN system.

17 shows an example of a MAC frame.

18 shows an example of a channel used / supported / defined within the 2.4 GHz band.

19 shows an example of a channel used / supported / defined within the 5 GHz band.

20 shows an example of a channel used / supported / defined within the 6 GHz band.

21 shows an example of channel bonding.

FIG. 22 is a diagram for describing technical features of a link used for multilink. FIG.

23 shows the first format of the EHT Operation Element.

24 shows a second format of the EHT Operation Element.

25 shows a third format of the EHT Operation Element.

26 shows a fourth format of the EHT Operation Element.

27 illustrates an example of an operation of an STA that does not support multilink.

28 shows another example of an operation of an STA that does not support multi-link.

29 illustrates another example of an operation of an STA that does not support multilink.

30 shows another example of an operation of an STA that does not support multi-link.

31 is a flowchart for explaining an example of an operation of an STA that does not support multi-link.

32 is a flowchart illustrating an example of an operation of an AP connected to an STA that does not support multi-link.

33 illustrates an example of an operation of a STA that supports multilink.

34 shows another example of an operation of an STA supporting multilink.

35 shows another example of an operation of an STA supporting multilink.

36 is a flowchart illustrating an example of an operation of an STA that supports multilink.

FIG. 37 is a flowchart illustrating an example of an operation of an AP connected to an STA supporting multilink.

38 illustrates an AP or STA to which an example of the present specification is applied.

39 shows another example of a detailed block diagram of a transceiver.

In the present specification, when there is a statement that a configuration includes specific elements, or when a process includes specific steps, it means that other elements or other steps may be further included. That is, the terms used in the present specification are only for describing specific embodiments and are not intended to limit the concept of the present specification.

As used herein, the slash (/) or comma (comma) may mean "and / or". For example, “A / B” means “A and / or B” and may mean “only A”, “only B” or “A and B”. In addition, technical features that are separately described in one drawing may be implemented separately or may be simultaneously implemented.

In addition, parentheses used herein may mean “for example”. Specifically, when it is displayed as "control information (Signal)", "Signal" may be proposed as an example of "control information". In addition, even when displayed as “control information (ie, signal)”, “signal” may be proposed as an example of “control information”.

The following example of the present specification can be applied to various wireless communication systems. For example, the following example of the present specification may be applied to a wireless local area network (WLAN) system. For example, the present specification may be applied to the IEEE 802.11a / g / n / ac standard or the IEEE 802.11ax standard. In addition, the present specification may be applied to the newly proposed EHT standard or the IEEE 802.11be standard. In addition, an example of the present specification may be applied to a new WLAN standard that improves the EHT standard or IEEE 802.11be.

Hereinafter, the technical features of the WLAN system to which the present specification may be applied to describe the technical features of the present specification are described.

1 is a conceptual diagram of a layer architecture of a WLAN system supported by IEEE 802.11. Referring to FIG. 1, a hierarchical architecture of a WLAN system includes a physical medium dependent (PMD) sublayer 100, a physical layer convergence procedure (PLCP) sublayer ( 110 and a medium access control (MAC) sublayer 120.

The PMD sublayer 100 may serve as a transmission interface for transmitting and receiving data between a plurality of STAs. The PLCP sublayer 110 is implemented such that the MAC sublayer 120 can operate with a minimum dependency on the PMD sublayer 100.

The PMD sublayer 100, the PLCP sublayer 110, and the MAC sublayer 120 may conceptually include management entities, respectively. For example, the management unit of the MAC sublayer 120 is referred to as a MAC Layer Management Entity (MLME) 125. The management unit of the physical layer is referred to as a PHY Layer Management Entity (PLME) 115.

Such management units may provide an interface for performing a layer management operation. For example, the PLME 115 may be connected to the MLME 125 to perform management operations of the PLCP sublayer 110 and the PMD sublayer 100. The MLME 125 may be connected to the PLME 115 to perform a management operation of the MAC sublayer 120.

In order for the correct MAC layer operation to be performed, a STA management entity (hereinafter, referred to as 'SME', 150) may exist. The SME 150 may be operated as an independent component in each layer. The PLME 115, the MLME 125, and the SME 150 may transmit and receive information from each other based on primitives.

The operation of each sub-layer is briefly described as follows. For example, the PLCP sublayer 110 may include a MAC protocol data unit (MAC protocol data unit) received from the MAC sublayer 120 according to an indication of the MAC layer between the MAC sublayer 120 and the PMD sublayer 100. Hereinafter, the MPDU is transmitted to the PMD sublayer 100 or the frame coming from the PMD sublayer 100 is transferred to the MAC sublayer 120.

The PMD sublayer 100 may be a PLCP lower layer to perform data transmission and reception between a plurality of STAs through a wireless medium. The MPDU delivered by the MAC sublayer 120 is referred to as a physical service data unit (hereinafter referred to as a 'PSDU') in the PLCP sublayer 110. The MPDU is similar to the PSDU. However, when an aggregated MPDU (AMPDU) that aggregates a plurality of MPDUs is delivered, individual MPDUs and PSDUs may be different from each other.

The PLCP sublayer 110 adds an additional field including information required by the transceiver of the physical layer in the process of receiving the PSDU from the MAC sublayer 120 and transmitting the PSDU to the PMD sublayer 100. In this case, the added field may be a PLCP preamble, a PLCP header, tail bits required to return a convolutional encoder to a zero state in the PSDU.

The PLCP sublayer 110 adds the above-mentioned fields to the PSDU to generate a PHY Protocol Data Unit (PPDU) to transmit to the receiving station via the PMD sublayer 100, and the receiving station receives the PPDU to receive the PLCP preamble and PLCP. Obtain and restore information necessary for data restoration from the header.

A STA is any functional medium that includes medium access control (MAC) and physical layer interface to a wireless medium that is compliant with the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. May be used to mean both an AP and a non-AP STA (Non-AP Station).

The STA may include a mobile terminal, a wireless device, a wireless transmit / receive unit (WTRU), a user equipment (UE), a mobile station (MS), a mobile subscriber unit ( It may also be called various names such as a mobile subscriber unit) or simply a user.

2 shows an example of a WLAN system.

As shown, the WLAN system includes at least one access point (AP) and a plurality of STAs associated with the AP (520a / b / c / e / d / f / g / h / i / j / k). ). Multiple STAs in the example of FIG. 2 may perform the functions of an AP and / or non-AP. The plurality of STAs 520a / b / c / e / d / f / g / h / i / j / k of FIG. 2 may be called various names such as a user terminal (UT). Also, at least one STA 520f of FIG. 2 may route / relay communication between the plurality of APs 510a / b, perform control on the plurality of APs, or transmit the plurality of APs 510a / b to the plurality of APs 510a / b. Control of the connected STA may be performed.

Also, the AP 510a / b of FIG. 2 is connected to the system controller 530 to communicate with other APs, or other network entities other than the other APs (for example, network entities or Internet servers defined by the 3GPP standard). Communicate with

A plurality of STAs shown in FIG. 2 may configure a basic service set (BSS).

The BSSs 100 and 105 are sets of APs and STAs such as APs and STAs that can successfully synchronize and communicate with each other, and do not indicate a specific area. The BSS may include one or more joinable STAs in one AP.

The BSS may include at least one STA, an AP providing a distribution service, and a distributed system connecting a plurality of APs.

The distributed system may configure an extended service set (ESS), which is an extended service set by connecting multiple BSSs. The ESS may be used as a term indicating one network in which one or several APs are connected through a distributed system. APs included in one ESS may have the same service set identification (SSID).

The portal may serve as a bridge for connecting the WLAN network (IEEE 802.11) with another network (for example, 802.X).

Even without an AP, a STA may establish a network and perform communication. Such a network may be referred to as an Ad-Hoc network or an independent basic service set (BSS).

3 is a diagram illustrating a frequency domain used in a WLAN system.

The WLAN system may use at least one channel defined within the 2.4 GHz band. The 2.4 GHz band may be called another name such as the first band.

As shown in FIG. 3, 14 channels may be configured in the .4 GHz band. Each channel may be set to a frequency domain (or bandwidth) of 20 MHz. F0 may represent a center frequency. The center frequency of the channel in the 2.4 GHz band may be configured at intervals of about 5 MHz except for channel 14. Adjacent ones of the fourteen channels may overlap each other. In each country, the maximum power level in the allowable frequency channel or the allowable frequency channel may be set differently. For example, channel 13 is not allowed in North America but may be allowed in most countries.

Specific numerical values shown in the example of FIG. 3 may be changed.

4 illustrates an example of network discovery / discovery.

In order to access the WLAN network, the STA must perform discovery on the network. Such discovery may be performed through a scanning process for a network. The scanning method may be divided into active scanning and passive scanning.

As shown in FIG. 4, an STA performing active scanning may transmit a probe request frame and wait for a response to discover which AP exists in the vicinity while moving channels. The responder may transmit a probe response frame to the STA that transmitted the probe request frame in response to the probe request frame. The responder may be the STA that last transmitted the beacon frame in the BSS of the channel being scanned. In the BSS, since the AP transmits a beacon frame, the AP becomes a responder. In the IBSS, since the STAs in the IBSS transmit a beacon frame, the responder may be changed.

When the STA transmits a probe request frame through channel 1 and receives a probe response frame through channel 1, the STA stores BSS-related information included in the received probe response frame and stores the next channel (for example, Channel 2) to repeat scanning in the same way.

As shown in FIG. 4, the scanning operation may also be performed by a passive scanning method. An STA performing scanning based on passive scanning may receive a beacon frame while moving channels.

A beacon frame is an example of a management frame in IEEE 802.11. The beacon frame may be transmitted periodically. Upon receiving the beacon frame, the STA may store BSS related information included in the received beacon frame, move to the next channel, and perform passive scanning on the next channel.

Although not shown in FIG. 4, a number of procedures may be performed after the scanning procedure of FIG. 4.

For example, an authentication process may be performed after the scanning procedure. The authentication process may include a process in which the STA transmits an authentication request frame to the AP, and in response thereto, the AP transmits an authentication response frame to the STA. An authentication frame used for authentication request / response corresponds to a management frame.

The authentication frame includes an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a Robust Security Network, and a finite cyclic group. Group) and the like.

The STA may transmit an authentication request frame to the AP. The AP may determine whether to allow authentication for the corresponding STA based on the information included in the received authentication request frame. The AP may provide a result of the authentication process to the STA through an authentication response frame.

The successfully authenticated STA may perform an association process. The association process includes a process in which the STA transmits an association request frame to the AP, and in response thereto, the AP transmits an association response frame to the STA. For example, the connection request frame may include information related to various capabilities, beacon listening interval, service set identifier (SSID), supported rates, supported channels, RSN, and mobility domain. It may include information about supported operating classes, TIM Broadcast Indication Map Broadcast request, interworking service capability, and the like. For example, the connection response frame may include information related to various capabilities, status codes, association IDs (AIDs), support rates, enhanced distributed channel access (EDCA) parameter sets, received channel power indicators (RCPIs), received signal to noise Information, such as an indicator, a mobility domain, a timeout interval (association comeback time), an overlapping BSS scan parameter, a TIM broadcast response, and a QoS map.

5 shows an example of a PPDU transmitted and received by an STA of the present specification.

5 illustrates representative fields of the PPDU, and the order of the fields illustrated in FIG. 5 may be variously changed.

The PPDU of FIG. 5 may include a short training field (STF) 510.

The STF 510 may be embodied as L-STF, HT-STF, VHT-STF, HE-STF, EHT-STF, and the like described later. The STF 510 may be used for frame detection, automatic gain control (AGC), diversity detection, coarse frequency / time synchronization, and the like.

The PPDU of FIG. 5 may include a long training field 520.

The LTF 520 may be embodied as L-LTF, HT-LTF, VHT-LTF, HE-LTF, EHT-LTF, and the like described later. LTF 520 may be used for fine frequency / time synchronization and channel prediction.

The PPDU of FIG. 5 may include an SIG 530.

The SIG 530 may be embodied as L-SIG, HT-SIG, VHT-SIG, HE-SIG, EHT-SIG, and the like described later. SIG 530 may include control information for decoding the PPDU.

The PPDU of FIG. 5 may include a Data field 540.

The data field 540 may include a SERVICE field 541, a physical layer service data unit (PSDU) 542, a PPDU TAIL bit 543, and a padding bit 544. Some bits of the SERVICE field 541 may be used for synchronization of the descrambler at the receiving end. The PSDU 542 may correspond to a MAC Protocol Data Unit (MPDU) defined in the MAC layer and may include data generated / used in an upper layer. The PPDU TAIL bit 543 may be used to return the encoder to zero state. The padding bit 544 may be used to adjust the length of the data field in a predetermined unit.

6 shows an example of a PPDU according to a conventional WLAN standard.

The PPDU shown in sub-a of FIG. 6 is an example of the PPDU used in the IEEE 802.11a / g standard.

The PPDU shown in FIG. 6B is an example of a PPDU used in the IEEE 802.11n standard.

7 shows another example of a PPDU according to a conventional WLAN standard.

7 shows an example of a PPDU according to the IEEE 802.11ac standard. Common fields shown include conventional L-STF, L-LTF, L-SIG, and also include the VHT-SIG-A field newly proposed in the IEEE 802.11ac standard. The PPDU of FIG. 7 may be used both in a single user (SU) communication in which a signal is transmitted from an AP to one user STA, and in a multi user (MU) communication in which a signal is transmitted from an AP to a plurality of user STAs. When MU communication is performed, the VHT-SIG-A field includes common control information that is commonly applied to all receiving STAs.

The Per-User fields shown in FIG. 7 include fields transmitted for at least one User STA when MU communication is performed. The VHT-STF field is a newly proposed STF field in the VHT standard (ie, IEEE 802.11ac), and the VHT-LTF field is an LTF field newly proposed in the VHT standard. The VHT-SIG-B field includes information for decoding the data field and may be configured individually for each receiving STA.

The PPDU of FIG. 7 may be transmitted to a plurality of STAs based on a multi-user multiple input (MU-MIMO) scheme. In addition, it may be transmitted to one STA based on the SU-MIMO technique.

8 is a diagram illustrating another example of the HE-PPDU.

8 may be applied to an IEEE 802.11ax or HE (high efficiency) WLAN system. The PPDU format according to IEEE 802.11ax is defined by four types. The example of FIG. 8 is an example of an MU-PPDU used for MU communication. However, some of the technical features applied to the field shown in FIG. 8 may be used as is for SU communication or UL-MU communication.

The technical features of the HE-PPDU illustrated in FIG. 8 may be applied to the EHT-PPDU to be newly proposed. For example, the technical feature applied to the HE-SIG may be applied to the EHT-SIG, and the technical feature applied to the HE-STF / LTF may be applied to the EHT-SFT / LTF.

The L-STF of FIG. 8 may include a short training orthogonal frequency division multiplexing symbol. The L-STF may be used for frame detection, automatic gain control (AGC), diversity detection, and coarse frequency / time synchronization.

The L-LTF of FIG. 8 may include a long training orthogonal frequency division multiplexing symbol. L-LTF may be used for fine frequency / time synchronization and channel prediction.

The L-SIG of FIG. 8 may be used to transmit control information. The L-SIG may include information about a data rate and a data length. In addition, the L-SIG may be repeatedly transmitted. That is, the L-SIG may be configured in a repeating format (for example, may be referred to as R-LSIG).

The HE-SIG-A of FIG. 8 may include control information common to the receiving station.

Specifically, the HE-SIG-A includes 1) a DL / UL indicator, 2) a BSS color field which is an identifier of a BSS, 3) a field indicating a remaining time of a current TXOP interval, and 4) 20, 40, and 80 Bandwidth field indicating whether 160, 80 + 80 MHz, 5) field indicating the MCS scheme applied to HE-SIG-B, 6) dual subcarrier modulation for HE-SIG-B for MCS ) Field indicating whether the modulation is performed by the scheme, 7) a field indicating the number of symbols used for the HE-SIG-B, 8) a field indicating whether the HE-SIG-B is generated over the entire band, 9 11) a field indicating the number of symbols of the HE-LTF, 10) a field indicating the length of the HE-LTF and a CP length, 11) a field indicating whether additional OFDM symbols exist for LDPC coding, and 12) a PE (Packet). Extension) field, and 13) information indicating a field indicating information about the CRC field of HE-SIG-A. . Specific fields of the HE-SIG-A may be added or omitted. In addition, some fields may be added or omitted in other environments where the HE-SIG-A is not a multi-user (MU) environment.

As described above, the HE-SIG-B of FIG. 8 may be included only in case of a PPDU for a multi-user (MU). Basically, the HE-SIG-A or the HE-SIG-B may include resource allocation information (or virtual resource allocation information) for at least one receiving STA.

The HE-STF of FIG. 8 may be used to improve automatic gain control estimation in a multiple input multiple output (MIMO) environment or an OFDMA environment.

The HE-LTF of FIG. 8 may be used to estimate a channel in a MIMO environment or an OFDMA environment.

The size of the FFT / IFFT applied to the fields after the HE-STF and the HE-STF of FIG. 8 may be different from the size of the FFT / IFFT applied to the field before the HE-STF. For example, the size of the FFT / IFFT applied to the HE-STF and the field after the HE-STF may be four times larger than the size of the IFFT applied to the field before the HE-STF.

For example, when at least one field of L-STF, L-LTF, L-SIG, HE-SIG-A, and HE-SIG-B on the PPDU of FIG. 8 is called a first field / part, a data field, HE At least one of -STF and HE-LTF may be referred to as a second field / part. The first field may include a field related to a legacy system, and the second field may include a field related to a HE system. In this case, the FFT (fast Fourier transform) size / inverse fast Fourier transform (IFFT) size is N times the FFT / IFFT size used in the conventional WLAN system (N is a natural number, for example, N = 1, 2, 4) can be defined. That is, an FFT / IFFT of N (= 4) times size may be applied to the second field of the HE PPDU compared to the first field of the HE PPDU. For example, 256 FFT / IFFT is applied for a bandwidth of 20 MHz, 512 FFT / IFFT is applied for a bandwidth of 40 MHz, 1024 FFT / IFFT is applied for a bandwidth of 80 MHz, and 2048 FFT for a bandwidth of 160 MHz continuous or discontinuous 160 MHz. / IFFT can be applied.

In other words, the subcarrier spacing / subcarrier spacing is 1 / N times the size of the subcarrier space used in the conventional WLAN system (N is a natural number, for example, 78.125 kHz when N = 4). Can be. That is, a subcarrier spacing of 312.5 kHz, which is a conventional subcarrier spacing, may be applied to the first field / part of the HE PPDU, and a subcarrier space of 78.125 kHz may be applied to the second field / part of the HE PPDU.

Alternatively, the IDFT / DFT period applied to each symbol of the first field may be expressed as N (= 4) times shorter than the IDFT / DFT period applied to each data symbol of the second field. . That is, the IDFT / DFT length applied to each symbol of the first field of the HE PPDU is 3.2 μs, and the IDFT / DFT length applied to each symbol of the second field of the HE PPDU is 3.2 μs * 4 (= 12.8 μs). Can be expressed as The length of an OFDM symbol may be a value obtained by adding a length of a guard interval (GI) to an IDFT / DFT length. The length of the GI can be various values such as 0.4 μs, 0.8 μs, 1.6 μs, 2.4 μs, 3.2 μs.

As described above, a technical feature in which subcarrier spacings of different sizes are applied to one PPDU may be applied to the EHT-PPDU. That is, subcarrier spacing of 312.5 kHz may be applied to the first part / part of the EHT-PPDU, and subcarrier space of 78.125 kHz may be applied to the second field / part of the EHT PPDU. The first portion / part of the EHT-PPDU may comprise L-LTF, L-STF, L-SIG, EHT-SIG-A, and / or EHT-SIG-B. In addition, the second part / part of the EHT-PPDU may include an EHT-STF, an EHT-LTF, and / or a data field. The division of the first part / second part of the EHT-PPDU may be changed.

Hereinafter, a resource unit (RU) used in a PPDU is described. The resource unit may include a plurality of subcarriers (or tones). The resource unit may be used when transmitting signals to a plurality of STAs based on the OFDMA technique. In addition, a resource unit may be defined even when transmitting a signal to one STA. Resource units may be used for STFs, LTFs, data fields and the like.

9 is a diagram illustrating an arrangement of resource units (RUs) used on a 20 MHz band.

As shown in FIG. 9, resource units (RUs) corresponding to different numbers of tones (ie, subcarriers) may be used to configure some fields of the HE-PPDU. For example, resources may be allocated in units of RUs shown for HE-STF, HE-LTF, and data fields.

As shown at the top of FIG. 9, 26-units (ie, units corresponding to 26 tones) may be arranged. Six tones may be used as the guard band in the leftmost band of the 20 MHz band, and five tones may be used as the guard band in the rightmost band of the 20 MHz band. In addition, seven DC tones are inserted into the center band, that is, the DC band, and there may be 26 units corresponding to each of 13 tones to the left and right of the DC band. In addition, other bands may be allocated 26-unit, 52-unit, 106-unit. Each unit can be assigned for a receiving station, ie a user.

Meanwhile, the RU arrangement of FIG. 9 is utilized not only for a situation for a plurality of users (MU) but also for a situation for a single user (SU), in which case one 242-unit is shown as shown in the bottom of FIG. It is possible to use and in this case three DC tones can be inserted.

In the example of FIG. 9, various sizes of RUs, that is, 26-RU, 52-RU, 106-RU, 242-RU, and the like have been proposed. Since the specific sizes of these RUs can be expanded or increased, the present embodiment Is not limited to the specific size of each RU (ie, the number of corresponding tones).

10 is a diagram illustrating an arrangement of resource units (RUs) used on a 40 MHz band.

Just as RUs of various sizes are used in the example of FIG. 11, the example of FIG. 10 may also use 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, and the like. In addition, five DC tones can be inserted at the center frequency, 12 tones are used as the guard band in the leftmost band of the 40 MHz band, and 11 tones are in the rightmost band of the 40 MHz band. This guard band can be used.

Also, as shown, the 484-RU may be used when used for a single user. Meanwhile, the specific number of RUs may be changed as in the example of FIG. 9.

11 is a diagram illustrating an arrangement of resource units (RUs) used on an 80 MHz band.

Just as RUs of various sizes are used in the example of FIGS. 9 and 10, the example of FIG. 11 may also use 26-RU, 52-RU, 106-RU, 242-RU, 484-RU, 996-RU, or the like. have. In addition, seven DC tones can be inserted in the center frequency, 12 tones are used as the guard band in the leftmost band of the 80 MHz band, and 11 tones in the rightmost band of the 80 MHz band. This guard band can be used. You can also use 26-RU with 13 tones each located to the left and right of the DC band.

Also, as shown, when used for a single user, a 996-RU may be used, in which case five DC tones may be inserted.

On the other hand, the specific number of RU can be changed is the same as the example of Figure 9 and 10.

9 to 11 may be used for OFDMA based communication. That is, any one RU (26/52/106 / 242-RU, etc.) illustrated in FIGS. 9 to 11 may be allocated to one STA, and the other RU may be allocated to another STA. That is, MU communication is possible by allocating the RUs shown in FIGS. 9 to 11 to a plurality of STAs. MU communication applies to downlink communication as well as to uplink communication.

The MU PPDU shown in FIG. 8 may be used for DL MU communication. That is, DL-MU communication is possible through OFDMA and / or MU-MIMO scheme based on the PPDU of FIG. 8.

In addition, the wireless LAN system supports UL MU communication. Trigger frame is defined for UL MU communication. The trigger frame may include ID information for a plurality of STAs participating in UL MU communication and radio resources (eg, RU information) used for UL MU communication.

12 shows an example of UL MU communication.

According to the example of FIG. 12, the AP transmits a trigger frame 1330. The trigger frame is defined in the form of a MAC frame, and may be included in a PPDU of various formats and transmitted from the AP. That is, when the PPDU including the trigger frame 1330 is received by the STA, UL MU communication starts after a short interframe space (SIFS) period. In more detail, the plurality of STAs (ie, STA 1 to STA n) indicated by the trigger frame 1330 performs UL-MU communication based on the uplink resources (ie, RU) indicated by the trigger frame 1330. . In more detail, the plurality of STAs (that is, STA 1 to STA n) transmits a trigger based (TB) PPDU according to the IEEE 802.11ax standard to the AP. A plurality of TB PPDUs transmitted by a plurality of STAs are transmitted in the same time interval, and information about the same time interval may be included in the trigger frame 1330. Thereafter, the AP may transmit ACK / NACK signals for the TB PPDUs 1342 and 1342 through a block ACK (BA). The UL MU communication may be performed within a TXOP 1325 interval obtained by the AP.

13 shows an example of a trigger frame. The trigger frame of FIG. 13 allocates resources for uplink multiple-user transmission and can be transmitted from the AP. The trigger frame may consist of a MAC frame and may be included in a PPDU.

Each field shown in FIG. 13 may be partially omitted, and another field may be added. In addition, each length can be varied as shown.

The frame control field 1310 of FIG. 13 includes information about the version of the MAC protocol and other additional control information, and the duration field 1320 sets a network allocation vector (NAV) described below. Time information for the UE or information on an identifier (eg, AID) of the UE.

In addition, the RA field 1330 includes address information of a reception STA of a corresponding trigger frame and may be omitted as necessary. The TA field 1340 includes address information of an STA (for example, an AP) that transmits a corresponding trigger frame, and the common information field 1350 has a common value applied to a receiving STA that receives the corresponding trigger frame. Contains control information

14 shows an example of a common information field. Some of the subfields of FIG. 10 may be omitted, and other subfields may be added. In addition, the length of each illustrated subfield may be modified.

The illustrated length field 1410 has the same value as the length field of the L-SIG field of the uplink PPDU transmitted corresponding to the corresponding trigger frame, and the length field of the L-SIG field of the uplink PPDU indicates the length of the uplink PPDU. As a result, the length field 1410 of the trigger frame may be used to indicate the length of the corresponding uplink PPDU.

In addition, the cascade indicator field 1420 indicates whether a cascade operation is performed. The cascade operation means that downlink MU transmission and uplink MU transmission are performed together in the same TXOP. That is, after downlink MU transmission is performed, it means that uplink MU transmission is performed after a predetermined time (eg, SIFS). Only one transmitting device (for example, AP) for downlink communication may be present and a plurality of transmitting devices (for example, non-AP) for uplink communication may exist during the casecade operation.

The CS request field 1430 indicates whether the receiver, which has received the trigger frame, should consider the state of the radio medium, the NAV, etc. in a situation in which the corresponding uplink PPDU is transmitted.

The HE-SIG-A information field 1440 may include information for controlling the content of the SIG-A field (ie, the HE-SIG-A field) of the uplink PPDU transmitted in response to the corresponding trigger frame.

The CP and LTF type field 1450 may include information about the length of the LTF and the CP length of the uplink PPDU transmitted in response to the corresponding trigger frame. The trigger type field 1460 may indicate the purpose for which the corresponding trigger frame is used, for example, normal triggering, triggering for beamforming, a request for Block ACK / NACK, and the like.

On the other hand, the remaining description with respect to Figure 13 is added as follows.

It is preferable to include per user information fields 1360 # 1 to 1360 # N corresponding to the number of receiving STAs receiving the trigger frame of FIG. 13. The individual user information field may be called a “RU assignment field”.

In addition, the trigger frame of FIG. 13 may include a padding field 1370 and a frame check sequence field 1380.

Each of the per user information fields 1360 # 1 to 1360 # N shown in FIG. 13 preferably includes a plurality of subfields.

15 shows an example of a subfield included in a per user information field. Some of the subfields of FIG. 15 may be omitted, and other subfields may be added. In addition, the length of each illustrated subfield may be modified.

The user identifier field 1510 of FIG. 15 indicates an identifier of an STA (ie, a receiving STA) to which per user information corresponds. An example of the identifier may be all or part of an AID. have.

In addition, an RU Allocation field 1520 may be included. That is, when the receiving STA identified by the user identifier field 1510 transmits an uplink PPDU in response to the trigger frame of FIG. 9, the corresponding uplink PPDU is transmitted through the RU indicated by the RU Allocation field 1520. Send. In this case, the RU indicated by the RU Allocation field 1520 preferably indicates the RU shown in FIGS. 9, 10, and 11.

The subfield of FIG. 15 may include a coding type field 1530. The coding type field 1530 may indicate a coding type of an uplink PPDU transmitted in response to the trigger frame of FIG. 13. For example, when BCC coding is applied to the uplink PPDU, the coding type field 1530 is set to '1', and when LDPC coding is applied, the coding type field 1530 is set to '0'. Can be.

In addition, the subfield of FIG. 15 may include an MCS field 1540. The MCS field 1540 may indicate an MCS scheme applied to an uplink PPDU transmitted in response to the trigger frame of FIG. 13.

Meanwhile, the STA may transmit various feedback schedules (eg, a Buffer Status Report or channel status information) based on UL OFDMA Random Access (UORA) defined according to the IEEE 802.11ax standard.

FIG. 16 is a diagram illustrating a method of performing UORA in a WLAN system.

As shown, the AP may allocate six RU resources as shown in FIG. 16 through a trigger frame (eg, FIGS. 13-15). Specifically, the AP includes a first RU resource (AID 0, RU 1), a second RU resource (AID 0, RU 2), a third RU resource (AID 0, RU 3), and a fourth RU resource (AID 2045, RU). 4), the fifth RU resources (AID 2045, RU 5) and the sixth RU resources (AID 2045, RU 6) may be allocated. Information about AID 0 or AID 2045 may be included in, for example, the user identification field 1110 of FIG. 11. Information about RU 1 to RU 6 may be included, for example, in the RU allocation field 1120 of FIG. 11. AID = 0 may mean a UORA resource for an associated STA, and AID = 2045 may mean a UORA resource for an un-associated STA. Accordingly, the first to third RU resources of FIG. 16 may be used as UORA resources for the associated STA, and the fourth to fifth RU resources of FIG. 16 may be used for the un-associated STA. It may be used as a UORA resource, and the sixth RU resource of FIG. 16 may be used as a resource for a conventional UL MU.

In the example of FIG. 16, an OFDMA random access backoff (OBO) counter of STA1 is reduced to 0, so that STA1 randomly selects second RU resources AID 0 and RU 2. In addition, since the OBO counter of STA2 / 3 is larger than 0, no uplink resource is allocated to STA2 / 3. In addition, in FIG. 16, since STA4 includes its AID (ie, AID = 3) in the trigger frame, resources of RU 6 are allocated without backoff.

Specifically, since STA1 of FIG. 16 is an associated STA, there are three eligible RA RUs for STA1 (RU 1, RU 2, and RU 3). Accordingly, STA1 decrements the OBO counter by 3 so that the OBO counter is reduced. It became zero. In addition, since STA2 of FIG. 16 is an associated STA, there are three eligible RA RUs for STA2 (RU 1, RU 2, and RU 3). Accordingly, STA2 decreases the OBO counter by 3, but the OBO counter is 0. It is a bigger state. In addition, since STA3 of FIG. 16 is an un-associated STA, there are two eligible RA RUs for STA3 (RU 4 and RU 5). Accordingly, STA3 decreases the OBO counter by 2, but the OBO counter is not. Is greater than zero.

17 shows an example of a MAC frame.

The MAC frame of FIG. 17 may be included in the PSDU included in the data field of the PPDU. The length of each field shown in FIG. 17 may be changed, and some of the fields may be omitted. As shown, the MAC frame may include a MAC header.

The data field may include a SERVICE field, a physical layer service data unit (PSDU), a PPDU TAIL bit, and may also include a padding bit if necessary. Some bits of the SERVICE field may be used for synchronization of the descrambler at the receiving end. The PSDU corresponds to a MAC Protocol Data Unit (MPDU) defined in the MAC layer and may include data generated / used in an upper layer. The PPDU TAIL bit can be used to return the encoder to zero state. The padding bit may be used to adjust the length of the data field in a predetermined unit.

The MPDU is defined according to various MAC frame formats, and the basic MAC frame is composed of a MAC header, a frame body, and a frame check sequence (FCS). The MAC frame may be composed of MPDUs and may be transmitted / received through the PSDU of the data portion of the PPDU frame format.

The MAC header includes a frame control field, a duration / ID field, an address field, and the like. The frame control field may include control information required for frame transmission / reception. The duration / ID field may be set to a time for transmitting the corresponding frame.

The duration / ID field included in the MAC header may be set to 16 bits long (e.b., B0 to B15). The content included in the period / ID field may vary depending on the frame type and subtype, whether the content is transmitted during the CFP (contention free period), the QoS capability of the transmitting STA, and the like. (i) In the control frame of which the subtype is PS-Poll, the duration / ID field may include the AID of the transmitting STA (e.g., via 14 LSB bits) and the 2 MSB bits may be set to one. (ii) In frames transmitted during CFP by a point coordinator (PC) or a non-QoS STA, the duration / ID field may be set to a fixed value (e.g., 32768). (iii) In other frames transmitted by the non-QoS STA or control frames transmitted by the QoS STA, the duration / ID field may include a duration value defined for each frame type. In a data frame or management frame transmitted by the QoS STA, the duration / ID field may include a duration value defined for each frame type. For example, when B15 = 0 of the duration / ID field indicates that the duration / ID field is used to indicate TXOP Duration, B0 to B14 may be used to indicate actual TXOP Duration. The actual TXOP Duration indicated by B0 to B14 may be any one of 0 to 32767, and its unit may be microseconds (us). However, when the duration / ID field indicates a fixed TXOP Duration value (e.g., 32768), it may be set to B15 = 1 and B0 to B14 = 0. In addition, when B14 = 1 and B15 = 1, the period / ID field is used to indicate an AID, and B0 to B13 indicate one AID of 1 to 2007.

The frame control field of the MAC header may include Protocol Version, Type, Subtype, To DS, From DS, More Fragment, Retry, Power Management, More Data, Protected Frame, and Order subfields.

The STA (AP and / or non-AP STA) herein may support multilink communication. An STA that supports multi-link communication may simultaneously perform communication through a plurality of links. That is, an STA that supports multi-link communication may perform communication through a plurality of links during a first time interval, and perform communication through only one of the plurality of links during a second time interval.

Multi-link communication may mean communication supporting a plurality of links, and the link may include one channel (eg, defined in a 2.4 GHz band, a 5 GHz band, a 6 GHz band, and / or a specific band described below. , 20/40/80/160/240/320 MHz channels). Hereinafter, various bands and channels will be described.

18 shows an example of a channel used / supported / defined within the 2.4 GHz band.

The 2.4 GHz band may be called another name such as the first band (band). Also, the 2.4 GHz band may refer to a frequency region in which a channel having a center frequency adjacent to 2.4 GHz (for example, a channel having a center frequency within 2.4 to 2.5 GHz) is used / supported / defined.

The 2.4 GHz band may contain multiple 20 MHz channels. 20 MHz in the 2.4 GHz band may have multiple channel indexes (eg, index 1 through index 14). For example, the center frequency of a 20 MHz channel to which channel index 1 is assigned may be 2.412 GHz, the center frequency of a 20 MHz channel to which channel index 2 is assigned may be 2.417 GHz, and 20 MHz to which channel index N is assigned. The center frequency of the channel may be (2.407 + 0.005 * N) GHz. The channel index may be called various names such as channel numbers. Specific values of the channel index and the center frequency may be changed.

18 exemplarily shows four channels in the 2.4 GHz band. The illustrated first frequency region 1810 to fourth frequency region 1840 may each include one channel. For example, the first frequency region 1810 may include channel 1 (20 MHz channel having index 1). In this case, the center frequency of channel 1 may be set to 2412 MHz. The second frequency domain 1820 may include channel 6. In this case, the center frequency of channel 6 may be set to 2437 MHz. The third frequency region 1830 may include channel 11. In this case, the center frequency of the channel 11 may be set to 2462 MHz. The fourth frequency region 1840 may include channel 14. In this case, the center frequency of channel 14 may be set to 2484 MHz.

19 shows an example of a channel used / supported / defined within the 5 GHz band.

The 5 GHz band may be called another name, such as the second band / band. The 5 GHz band may refer to a frequency region in which channels having a center frequency of 5 GHz or more and less than 6 GHz (or less than 5.9 GHz) are used / supported / defined. Alternatively, the 5 GHz band may include a plurality of channels between 4.5 GHz and 5.5 GHz. Specific numerical values shown in FIG. 19 may be changed.

The plurality of channels in the 5 GHz band includes UNII (Unlicensed National Information Infrastructure) -1, UNII-2, UNII-3, and ISM. UNII-1 can be called UNII Low. UNII-2 may include frequency domains called UNII Mid and UNII-2Extended. UNII-3 can be called UNII-Upper.

A plurality of channels may be set in the 5 GHz band, and the bandwidth of each channel may be variously set to 20 MHz, 40 MHz, 80 MHz, or 160 MHz. For example, the 5170 MHz to 5330 MHz frequency domain / range within UNII-1 and UNII-2 may be divided into eight 20 MHz channels. The 5170 MHz to 5330 MHz frequency domain / range can be divided into four channels through the 40 MHz frequency domain. The 5170 MHz to 5330 MHz frequency domain / range can be divided into two channels through the 80 MHz frequency domain. Alternatively, the 5170 MHz to 5330 MHz frequency domain / range may be divided into one channel through a 160 MHz frequency domain.

20 shows an example of a channel used / supported / defined within the 6 GHz band.

The 6 GHz band may be called another name such as the third band / band. The 6 GHz band may refer to a frequency region in which channels having a center frequency of 5.9 GHz or more are used / supported / defined. Specific numerical values shown in FIG. 20 may be changed.

For example, the 20 MHz channel of FIG. 20 may be defined from 5.940 GHz. In more detail, the left-most channel of the 20 MHz channel of FIG. 20 may have an index 1 (or a channel index, a channel number, etc.), and a center frequency may be allocated to 5.945 GHz. That is, the center frequency of the index N channel may be determined as (5.940 + 0.005 * N) GHz.

Accordingly, the index (or channel number) of the 20 MHz channel of FIG. 20 is 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, 197, 201, 205, 209, 213, 217, 221, 225, 229, 233. In addition, in accordance with the aforementioned (5.940 + 0.005 * N) GHz rule, the index of the 40 MHz channel of FIG. 20 is 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.

In the example of FIG. 20, 20, 40, 80, 160 MHz channels are shown, but additional 240 MHz channels or 320 MHz channels may be added.

The concept of conventional channel bonding is described below.

For example, in an IEEE 802.11n system, two 20 MHz channels may be combined to perform 40 MHz channel bonding. In addition, 40/80/160 MHz channel bonding may be performed in an IEEE 802.11ac system.

For example, the STA may perform channel bonding on the primary 20 MHz channel (P20 channel) and the secondary 20 MHz channel (S20 channel). In the channel bonding process, a backoff count / counter may be used. The backoff count value is selected as a random value and can be decreased during the backoff interval. In general, when the backoff count value reaches 0, the STA may attempt to access a channel.

When the STA performing channel bonding determines that the P20 channel is in the idle state during the backoff interval, and the backoff count value for the P20 channel becomes 0, the S20 channel may be used for a certain period of time (for example, a point coordination function). interframe space)) to determine whether the idle state has been maintained. If the S20 channel is in the idle state, the STA may perform bonding on the P20 channel and the S20 channel. That is, the STA may transmit a signal PPDU through a 40 MHz channel (that is, a 40 MHz bonding channel) including a P20 channel and an S20 channel.

21 shows an example of channel bonding. As shown in FIG. 21, the primary 20 MHz channel and the secondary 20 MHz channel may configure a 40 MHz channel (primary 40 MHz channel) through channel bonding. That is, the bonded 40 MHz channel may include a primary 20 MHz channel and a secondary 20 MHz channel.

Channel bonding may be performed when a channel continuous to the primary channel is in an idle state. That is, the primary 20 MHz channel, the secondary 20 MHz channel, the secondary 40 MHz channel, and the secondary 80 MHz channel may be sequentially bonded. If the secondary 20 MHz channel is determined to be busy, even if all the other secondary channels are idle, the channel may be bonded. Bonding may not be performed. In addition, when the secondary 20 MHz channel is in the idle state and the secondary 40 MHz channel is determined to be in the busy state, channel bonding may be performed only on the primary 20 MHz channel and the secondary 20 MHz channel.

The technical features for multilink and aggregation are described below.

The STA (AP and / or non-AP STA) herein may support multilink communication. That is, the STA may simultaneously transmit and receive a signal through the first link and the second link based on the multi link. That is, the multi-link may mean a technique in which one STA simultaneously transmits and receives a signal through a plurality of links. For example, transmitting signals over one link and receiving signals over another link may be included in the multi-link communication. An STA supporting multi-link may use a plurality of links in a first time interval and only one link in a second time interval.

FIG. 22 is a diagram for explaining technical features of a link used in a multi-link. FIG.

The link used for the multi-link may have at least one of the following technical features. Features related to the link described below are exemplary and additional technical features may be applied.

For example, each link used for the multi-link may be included in different bands. That is, when multi-links supporting the first and second links are used, each of the first link and the second link is included in the 2.4 GHz band, the 5 GHz band, or the 6 GHz band, but the first link and the second link May be included in different bands.

Referring to FIG. 22, a first link 2210 and a second link 2220 may be used for the multi link. The first link 2210 of FIG. 22 may be included, for example, in the 5 GHz band. The second link 2220 of FIG. 22 may be included, for example, in the 6 GHz band.

Each link used for the multi-link may be included in the same band. For example, if a multilink supporting the first / second / third link is used, all the links are included in the same band, or the first / second link is included in the first band and the third link is the first link. It can be included in two bands.

The multi-link may be configured based on different RF modules (eg, a transceiver including an IDFT / IFFT / DFT / FFT block and a base band processing device). Additionally or alternatively, a plurality of links included in the multi-link may be discontinuous in the frequency domain. That is, a frequency gap may exist in a frequency region corresponding to the first link and a frequency region corresponding to the second link among the plurality of links.

As shown in FIG. 22, the first link 2210 may include a plurality of channels 2211, 2212, 2213, and 2214. The STA may apply existing channel bonding for the plurality of channels 2211, 2212, 2213, and 2214. That is, when multiple channels 2211, 2212, 2213, and 2214 are idle for a specific time period (eg, during PIFS), the multiple channels 2211, 2212, 2213, and 2214 are connected to one bonding channel. It can be configured, one bonding channel can operate as one link 2210. Alternatively, some of the channels 2211, 2212, 2213, and 2214 (eg, 2211, 2212, and 2214) may operate as one link 2210 through the preamble puncturing technique newly proposed in the IEEE 802.11ax standard. . The above-described feature may be equally applied to the second link 2220.

An upper limit may be set on the number of channels (and / or the maximum bandwidth) included in one link used for the multi-link. For example, as in the example of FIG. 22, up to four channels may configure one link. Additionally or alternatively, the maximum bandwidth of one link may be 160 MHz, 240 MHz, 320 MHz. Additionally or alternatively, one link may include only contiguous channels. Specific values as above may be changed.

The procedure of identifying / specifying / determining the link used for the multi-link is related to the aggregation (or channel aggregation) procedure. An STA may aggregate multiple links to perform multilink communication. That is, the STA may perform 1) a first procedure of identifying / specifying / determining a link aggregated for the multi-link and 2) a second procedure of performing multi-link communication through the identified / specified / determined link. The STA may perform the first and second procedures as separate procedures or may simultaneously perform the same procedure through one procedure.

The technical features of the first procedure are described below.

The STA may transmit and receive information on a plurality of links configuring the multi link. For example, the AP may identify identification information about a band supported by the multi-link capability and / or a channel supported by the multi-link capability through a beacon, probe response, association response, or other control frame. Identification information can be transmitted. For example, when the AP can perform communication by aggregation of some channels in the 5 GHz band and some channels in the 6 GHz band, identification information about the aggregated channels may be transmitted to the user STA.

For example, the user STA may also identify identification of a band on which multilink capability is supported and / or identification of a channel on which multilink capability is supported through a probe request, association response, or other control frame. Information can be sent. For example, when the user STA can perform communication by collecting some channels in the 5 GHz band and some channels in the 6 GHz band, identification information about the aggregated channels may be transmitted to the AP.

One of a plurality of links constituting the multi-link may operate as a primary link. Primary Link can perform various functions. For example, the STA may perform aggregation on another link when the backoff-value of the primary link is 0 (and / or when the primary link is idle during PIFS). Information about the primary link may also be included in the Beacon, Probe Request / Response, and Association Request / Response.

The User-STA / AP can identify / determine / acquire bands and / or channels on which multilinks are performed through negotiation procedures that exchange information about their capabilities.

For example, the STA may be used for a first candidate band / channel that may be used for the first link through a negotiation procedure, a second candidate band / channel that may be used for the second link, and a third link. A third candidate band / channel can be specified / determined / acquired.

Thereafter, the STA may perform a procedure of identifying / specifying / determining a link aggregated for the multi-link. For example, the STA may be based on a backoff-count of the first candidate band / channel, the second candidate band / channel, the third candidate band / channel, and / or a clear channel assessment (CCA) sensing result (whether Busy / Idle). At least two bands / channels may be aggregated. For example, the STA may aggregate the second candidate bands / channels that have maintained the idle state for a specific period (during PIFS) when the backoff count value of the first candidate bands / channels is zero. That is, the STA determines / specifies a first candidate band / channel as a first link for multi-link, determines / specifies a second candidate band / channel as a second link for multi-link, and the first and second Multi-link communication can be performed over the link.

The technical features of the second procedure are described below.

For example, when the STA determines to aggregate the first and second links, the STA may perform multilink communication through the first and second links. For example, the STA may transmit PPDUs of the same length on both the first and second links. Alternatively, the STA may receive the transmission PPDU on the first link and receive the reception PPDU on the second link during the overlapping time interval. The STA may perform communication through all the aggregated links in a specific time interval, and may use only one link in another time interval.

STA (User-STA / AP) of the present specification may include a plurality of RF modules / units. For example, when the STA transmits signals in the 5 GHz and / or 6 GHz bands using the RF module / unit, the 2.4 GHz band, performance degradation may occur for the corresponding STA. Accordingly, the STA may additionally include an RF module / unit for the 2.4 GHz band that is distinguished from the RF module / unit for the 5 GHz and / or 6 GHz bands.

As described above, the STA of the present specification may operate in various bands / channels. Accordingly, an operation for transmitting accurate information about a band and / or a channel for a User-STA / AP should be defined.

The specification proposes a number of embodiments for this purpose.

At least one of the following examples (for example, the first embodiment) proposes an example for the AP to inform the neighboring STAs of an ultra wide band channel or a multi band channel of 160 MHz or more. Specifically, the present specification proposes an EHT operation element transmitted through a beacon frame, a probe response frame, or an association response frame. The EHT Operation Element proposed in this specification may be in a format according to the IEEE 802.11be standard. The EHT Operation Element may support the technical features described below.

Since at least one of the following examples (for example, the first embodiment) relates to an example for indicating an ultra wide band channel or a multi band channel of 160 MHz or more, the following technical features are not limited to the term EHT. That is, the term EHT may be changed / omitted, and the EHT operation element may be called various terms such as a new type of operation element or a first type of operation element. For example, the following technical features may be applied to a new wireless LAN standard that enhances the EHT standard or IEEE 802.11be.

First embodiment

Hereinafter, technical features related to the EHT Operation Element will be described for convenience of description.

The AP (or transmitting STA) may define information on an active channel in a specific element. That is, the element may include information about a channel on which the AP operates. The element may be included in a beacon frame transmitted periodically from the AP and transmitted to the STA. The STA may identify the information on the operation channel of the AP by receiving the beacon frame. In addition, when the element is included in a probe response frame or an association response frame and the STA requests the AP for information or connection to the channel, the element may be transmitted to the STA in response to the request.

In the IEEE 802.11n standard, 40 MHz channel information may be defined through the HT Operation Element. In addition, in the IEEE 802.11ac standard, information on an 80 MHz or 160 MHz channel may be defined through a VHT operation element. Since the IEEE 802.11ax standard does not explicitly define broadband channel transmission, the HE Operation Element may not include information on existing bands / channels. However, since the IEEE 802.11ax standard supports 6 GHz band operation, the HE Operation Element may include information about a channel in the 6 GHz band instead of information about an existing band channel. STAs (eg, EHT-STAs) supporting subsequent standards (e.g., IEEE 802.11be) after IEEE 802.11ax may support ultra-wideband channels of 160 MHz or more. In addition, the EHT-STA may transmit a signal through a channel within a plurality of bands (eg, 2.4 GHz or 5 GHz) or transmit a signal through a plurality of links. For example, one BSS can use up to 200 MHz channels using a 40 MHz channel in the 2.4 GHz band and a 160 MHz channel in the 5 GHz band.

The AP and / or STA according to the present specification includes four RF units and may operate in three bands of 2.4 GHz, 5 GHz, or 6 GHz. The number of RF units or the number of supported bands can be changed. According to an embodiment, the AP and / or STA may include four or more RF units. The AP and / or STA herein may operate in at least one band of 2.4 GHz, 5 GHz, 6 GHz, 60 GHz, or 900 MHz, and may also operate in another band.

This specification relates to a situation in which multiple channels are supported within one BSS. In this case, the STA may transmit and receive a signal through one or a plurality of channels. That is, the AP and / or STA may support a plurality of channels in the BSS. The STA may transmit a signal through at least one channel among a plurality of channels supported by the AP. At least one channel of the plurality of channels may be called various expressions such as link, session, or connection.

The EHT Operation Element may include operation channel information of the AP. The EHT Operation Element may include information related to at least one channel in a first band supported by the EHT standard. The VHT Operation Element may include information related to at least one channel in a second band supported by the VHT standard. The HT Operation Element may include an HT Operation Element including information related to at least one channel in a third band supported by the HT standard. According to an embodiment, the first band may include the aforementioned 6 GHz band. The second band may include the 5 GHz band described above. The third band may include the 2.4 GHz band described above.

 According to an embodiment, when the BSS operates in the 5 GHz and 6 GHz bands, the HT Operation Element may include 40 MHz of channel information (eg, information related to the primary 20 channel and information related to the secondary 20 channel) within 5 GHz. It may include. The VHT Operation Element may include channel information of 80 MHz or 160 MHz within 5 GHz. The EHT Operation Element may include channel information in the 6 GHz band. For example, if the AP (or transmitting STA) uses channel 42 (80 MHz) and channel 155 (80 MHz) within the 5 GHz band and channel 7 (80 MHz) within the 6 GHz band, Channel 7 information in the 6 GHz band may be included in the EHT operation element. Since the VHT-STA and the HE-STA may operate in a channel within the 5 GHz band of the corresponding BSS, the VHT Operation Element may include channel information within the 5 GHz band in which the VHT-STA and the HE-STA operate. Therefore, two channels (channel 42 and channel 155) information in the 5 GHz band may be included in the VHT operation element. Since the HT-STA may operate in a 40 MHz channel within a 5 GHz band of the corresponding BSS, the HT Operation Element may include band information for operating the HT-STA. The HT Operation Element may include Primary 20 MHz channel and Primary 40 MHz channel information in a 5 GHz band in which the HT-STA will operate.

In order to ensure backward compatibility with the existing STA, the EHT-STA may transmit the HT Operation Element and the VHT Operation Element together with the EHT Operation Element. Therefore, the EHT-STA may transmit only other information not included in the HT Operation Element and the VHT Operation Element to the EHT Operation Element to other STAs. The EHT-STA may transmit information not duplicated with the HT Operation Element and the VHT Operation Element to the EHT Operation Element. This can reduce overhead.

FIG. 23 illustrates a first format of the EHT Operation Element, and FIG. 24 may illustrate a second format of the EHT Operation Element. FIG. 23 may be a format for dividing and defining information about a band or RF not included in an operation element (for example, a VHT operation element or an HT operation element) according to a conventional standard for each band or RF. FIG. 24 may be in a format for defining information about an entire band or RF at once, which is not included in an operation element according to a conventional standard.

23 shows the first format of the EHT Operation Element.

In detail, the EHT Operation Element may include an Element ID field 2310, a Length field 2320, or an EHT Operation Information field 2330. The Element ID field 2310 may include information about an Element ID. The length field 2320 may include information about the number of octets after the length field 2320.

The EHT Operation Information field 2330 may include a Number of Band field 2340, a Channel Order field 2350, and / or a Band Info Tuples field 2360.

The number of band field 2340 may include information about the number of bands or RFs not included in the VHT Operation Element among the total bands or total RFs of the BSS. For example, the AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. The VHT Operation Element may include information about channel 42 and channel 155 in the 5 GHz band. Therefore, the EHT Operation Element may include only information on one channel 7 in the 6 GHz band. The Number of Band field 2340 in the EHT Operation Information field 2330 may have a first value (eg, {1}).

The channel order field 2350 may include information about the position of the primary channel. The channel order field 2350 may indicate information about the position of the primary channel through various methods. For example, the Channel Order field 2350 may indicate a Primary 20 MHz Channel within 160 MHz through a bitmap.

The Band Info Tuples field 2360 may include information about each band or RF. In detail, the Band Info Tuples field 2360 may be repeatedly configured to indicate information on a band / band or RF, except for channel information included in a VHT operation element. For example, the AP may transmit information about two RFs through the EHT operation element, except for channel information included in the VHT operation element. Accordingly, the Band Info Tuples field 2360 may be configured twice.

The Band Info Tuples field 2360 may include an Operating Class subfield 2370 or a Channel number subfield 2380.

The operating class subfield 2370 may include information about an operating class (or operation class) of each band or RF. An index indicating one set of sets of rules applied to the wireless device may be defined as corresponding to one operating class. For example, one set of rules may include a channel starting frequency, a channel spacing, a channel set, and a behavior limit set. It may be set differently for each country. For example, an AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. The VHT Operation Element may include information of an operating class indicating channel 42 and channel 155 in the 5 GHz band. Accordingly, the Operating Class subfield 2370 in the Band Info Tuples field 2360 may have a value (eg, {133}) indicating an 80 MHz channel in the 6 GHz band.

The channel number subfield 2380 may include information about a channel number of each band or RF. For example, an AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. The VHT Operation Element may include information about channel 42 and channel 155 in the 5 GHz band. Accordingly, the channel number subfield 2380 in the band info tuples field 2360 may have a value (eg, {7}) for indicating channel 7.

24 shows a second format of the EHT Operation Element.

The EHT Operation Element may include operation channel information of the AP. Unlike the first format illustrated in FIG. 23, the second format may be a format for defining information about the entire band or RF at once, which is not included in the VHT Operation Element.

The EHT Operation Information field 2430 includes a Band Control field 2431, a Channel Order field 2432, a 2.4 GHz Band Info field 2433, a 5 GHz Band Info field 2434, or a 6 GHz Band Info field 2435. can do.

The band control field 2431 may include information about a band or RF other than channel information included in the VHT operation element of the current BSS. The band control field 2431 may include information about a combination of a band or RF within 2.4 GHz, 5 GHz, and / or 6 GHz, except for channel information included in an operation element according to a conventional standard. For example, if the BSS operates on up to four RFs and three bands / bands, there may be about 50 combinations of bands or RF. The value of the band control field 2431 may be configured as a lookup table according to the combination of the band or the RF. For example, the value of the Band Control field 2431 may be configured with 8 bits. When the value of the Band Control field 2431 is {2}, that is, {00000010}, it may indicate that there are two RFs for the 5 GHz band and two RFs for the 6 GHz band. According to an embodiment, the AP may transmit a mapping relationship between the RF and the band to the receiving STA through the band control field 2431. The receiving STA may determine an optimal RF and band mapping relationship for communicating with the AP based on the mapping relationship between the RF and the band received from the AP.

The channel order field 2432 may include information about the position of the primary channel. The primary channel may mean a specific frequency region in which a beacon (or other control frame) can be transmitted. The channel order field 2432 may include information about the position of the primary channel through various methods. For example, the Channel Order field 2432 may indicate a Primary 20 MHz Channel within 160 MHz through a bitmap.

The 2.4 GHz Band Info field 2433 may include information about the 2.4 GHz band. In detail, the 2.4 GHz Band Info field 2433 may include information about a channel number and information about a channel width in the 2.4 GHz band.

The 5 GHz Band Info field 2434 may include information about a 5 GHz band. In detail, the 5 GHz Band Info field 2434 may include information about a channel number and information about a channel width in the 5 GHz band.

The 6 GHz Band Info field 2435 may include information about the 6 GHz band. In detail, the 6 GHz Band Info field 2435 may include information about a channel number and information about a channel width in the 6 GHz band.

The information about the channel number included in the 2.4 GHz Band Info field 2433, the 5 GHz Band Info field 2434, and the 6 GHz Band Info field 2435 is the center frequency (center) as described in FIGS. 9 to 10. frequency) and channel width (or frequency domain (eg, 20 MHz)). However, the information about the channel number may be defined differently for each country and may not include information about the channel width. Accordingly, the 2.4 GHz Band Info field 2433, the 5 GHz Band Info field 2434, and the 6 GHz Band Info field 2435 may additionally include information about the channel width as well as information about the channel number.

According to an embodiment of the present disclosure, the second type of the EHT operation element may further include information about an operating class in order to transmit information about a regulation (for example, TX power) related to a channel.

Hereinafter, another format of the EHT Operation Element will be described.

Unlike the FIGS. 23 to 24, the EHT operation element may include all operation channel information of the AP. For example, if the AP is using channel 42 (80 MHz) and channel 155 (80 MHz) in the 5 GHz band, and channel 7 (80 MHz) in the 6 GHz band, the EHT Operation Element is the 80 MHz channel 3 It can contain all information about dogs (240 MHz total) and two bands (5 GHz and 6 GHz).

The VHT Operation Element may include band information for operating the VHT-STA and the HE-STA. Therefore, some of the information included in the EHT operation element may be duplicated in the VHT operation element.

Since the EHT Operation Element can be newly configured separately from the VHT Operation Element or the HT Operation Element, it can support any combination of bands or RF that can operate in the EHT-STA. For example, if an AP uses three 80 MHz channels in the 5 GHz band, or if three bands of 2.4 GHz, 5 GHz, and 6 GHz are used, the AP can obtain information about all channels using the EHT Operation Element. Can be instructed.

FIG. 25 illustrates a third format of the EHT Operation Element, and FIG. 26 may illustrate a fourth format of the EHT Operation Element. FIG. 25 may be a format for dividing and defining information on a band or RF for each band or RF. FIG. 26 may be a format for defining information about an entire band or RF at once.

25 shows a third format of the EHT Operation Element.

In detail, the EHT Operation Element may include an Element ID field 2510, a Length field 2520, or an EHT Operation Information field 2530. The Element ID field 2510 may include information about an Element ID. The length field 2520 may include information about the number of octets after the length field 2520.

The EHT Operation Information field 2530 may include a Number of Band field 2540, a Channel Order field 2550, or a Band Info Tuples field 2560.

The number of band field 2540 may include information about the total number of bands or total number of RFs of the BSS. For example, the AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. Since channel 42 and channel 155 are discontinuous in the 5 GHz band, it may be desirable for the AP to include two RFs. In addition, in order to transmit the signal of channel 7 in the 6 GHz band, the AP may include one additional RF. That is, the AP may include a total of three RF. Accordingly, the Number of Band field 2540 in the EHT Operation Information field 2530 may have a first value (eg, {3}).

The channel order field 2550 may include information regarding the position of the primary channel. The channel order field 2550 may indicate information regarding the position of the primary channel through various methods. For example, the Channel Order field 2550 may indicate a Primary 20 MHz Channel within 160 MHz through a bitmap.

The Band Info Tuples field 2560 may include information about the number of each band or RF. In detail, the Band Info Tuples field 2560 may be repeatedly configured to indicate information about the total number of bands or the number of RFs. For example, an AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. The AP may require three RFs to use channels 42, 155, and 7 in the 6 GHz band in the 5 GHz band. Accordingly, the Band Info Tuples field 2560 may be configured three times.

The Band Info Tuples field 2560 may include an Operating Class subfield 2570 or a Channel number subfield 2580.

The operating class subfield 2570 may include information about an operating class of each band or RF. For example, an AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. The AP may require three RFs to use channels 42, 155, and 7 in the 6 GHz band in the 5 GHz band. Accordingly, the Band Info Tuples field 2560 may be configured three times. The Band Info Tuples field 2560 may include a first Band Info Tuples field, a second Band Info Tuples field, and a third Band Info Tuples field. Accordingly, the first Operating Class subfield in the first Band Info Tuples field including information about channel 42 may have a value (eg, {128}) indicating an 80 MHz channel in a 5 GHz band. The second Operating Class subfield in the second Band Info Tuples field including information on channel 155 may have a value (eg, {128}) indicating an 80 MHz channel in a 5 GHz band. The third Operating Class subfield in the third Band Info Tuples field including information on channel 7 may have a value (eg, {133}) indicating an 80 MHz channel in the 6 GHz band.

The channel number subfield 2580 may include information about a channel number of each band or RF. For example, an AP may use channel 42 (80 MHz) and channel 155 (80 MHz) within a 5 GHz band, and channel 7 (80 MHz) within a 6 GHz band. The Band Info Tuples field 2560 may include a first Band Info Tuples field, a second Band Info Tuples field, and a third Band Info Tuples field. Accordingly, the first channel number subfield in the first Band Info Tuples field may have a value (eg, {42}) indicating a channel 42 in the 5 GHz band. May have a value (eg, {155}) indicating channel 155 in the 5 GHz band. The third Channel number subfield in the third Band Info Tuples field may have a value (for example, {7}) indicating channel 7 in the 6 GHz band.

26 shows a fourth format of the EHT Operation Element.

The EHT Operation Element may include operation channel information of the AP. Unlike the third format illustrated in FIG. 25, the fourth format may be a format for defining information about the entire band or the RF at one time.

The EHT Operation Information field 2630 includes a Band Control field 2651, a Channel Order field 2632, a 2.4 GHz Band Info field 2633, a 5 GHz Band Info field 2634, or a 6 GHz Band Info field 2635. can do.

The band control field 2651 may include information about a band or RF of the current BSS. The band control field 2471 may include information about a combination of a band or RF within 2.4 GHz, 5 GHz, or 6 GHz. For example, if the BSS operates on up to four RFs and three bands, there may be about 100 combinations of bands or RF. The value of the band control field 2671 may be configured as a lookup table according to the combination of the band or the RF. For example, the value of the Band Control field 2671 may be configured with 8 bits. When the value of the Band Control field 2671 is {1}, that is, {00000001}, it may indicate that there are two RFs for the 5 GHz band and two RFs for the 6 GHz band. For another example, when the value of the Band Control field 2671 is {5}, that is, {00000101}, it may indicate that there is one RF for the 5 GHz band and three RF for the 6 GHz band.

The channel order field 2632 may correspond to the channel order field 2432 of FIG. 24.

The 2.4 GHz Band Info field 2633, the 5 GHz Band Info field 2634, and the 6 GHz Band Info field 2635 are the 2.4 GHz Band Info field 2433, the 5 GHz Band Info field 2434 and 6 GHz of FIG. 24. It may correspond to the Band Info field 2435.

Second embodiment

The second embodiment described below relates to technical features that may be performed together with the first embodiment. For example, while at least one of the plurality of fields of FIGS. 23 to 26 described in the first embodiment is transmitted and received, the information described below may be transmitted and received together. In addition, at least one of the plurality of fields of FIGS. 23 to 26 described in the first embodiment may be used during a process (discovery process, association process, or data transmission / reception link (or band) signaling process) described according to the second embodiment. Can be sent. The method according to the second embodiment may be applied to an STA or an AP according to the IEEE 802.11ax standard or the IEEE 802.11be standard.

Description of the AP

The AP herein can be described in various ways.

The AP is described in such a manner that a first RF supporting a first band / link, a second RF supporting a second band / link, and / or a third RF supporting a third band / link are included in one device. Can be. That is, one AP may be configured, and the AP may be described in a manner of supporting multiple bands / links.

The AP may be described in another way. For example, an AP may be described in such a way that the first to third APs are included in one device. The first AP may transmit and receive a signal of the first band / link. The second AP may transmit and receive a signal of the second band / link. The third AP may transmit and receive signals of the third band / link. The first AP, the second AP and / or the third AP may be co-located within one device. Also, the first AP, the second AP and / or the third AP may be controlled by one processor, and control information applied to any one AP may be shared by the processor to another AP.

In summary, an AP supporting a plurality of bands or links may be represented by one AP or may be represented by a set of a plurality of APs. For convenience of description, in the present specification, an AP supporting a plurality of bands / links will be described as being divided into a first AP, a second AP, and a third AP. However, since the first AP, the second AP, and the third AP are used to identify an operation band or a link, “first to third APs” used in the following second embodiment may be referred to as one AP. .

Specific operation according to the second embodiment

In this specification, depending on whether the STA supports multi-link (or multi-band), an operation after the STA is connected with the AP may be proposed. Hereinafter, the case in which the STA supports the multi link may be described first.

1. For STAs that do not support multilink (or multiband)

An STA that does not support the multi-link may perform a discovery process through the first link. In addition, the STA may perform the discovery process through the second link. Thereafter, the STA may perform an association process with the AP through the first link. The STA may transmit information about the second link to the AP via the first link. Based on the information about the second link, the STA may communicate with the AP via the second link.

An operation of an STA that does not support multi-link may be described through step A to step C below. In the following, a detailed description of step A to step C may be described later.

A. Discovery Process

A-i) If the STA does not support the multi-link, the AP may perform a scanning process on one of the operated multi-links.

For example, the AP may operate on a first link (or first band) and a second link (or second band). The AP may include a first AP supporting the first link or a second AP supporting the second link. The STA may support the first link and / or the second link. However, the STA may not support the multi link.

The STA may receive a beacon (or beacon frame) transmitted by the AP. The STA may discover an AP through the beacon. The STA may discover the AP by transmitting and receiving a Probe Request frame / Probe Response frame with the AP.

A-ii) Even if the AP supports multiple links, the AP may perform a discovery process through one link. For example, the AP may transmit a beacon (or beacon frame) only on one link. For another example, the AP may respond to the Probe Request frame only on a specific link.

A-iii) The STA may know that the AP supports multilink. According to the first embodiment of the present disclosure, the STA may confirm that the AP supports multilink.

A-iv) The STA may perform the discovery process through each of a plurality of links supported by the STA.

For example, the STA may perform a discovery process on the first link (or first band). The STA may also perform a discovery process on the second link (or the second band). The STA can discover one AP in both the first link and the second link. The STA may confirm that the AP can transmit and receive data through the first link and the second link.

Accordingly, the STA may select a link for transmitting and receiving data after the association process or the association process. For example, the STA may select one of the first link or the second link.

According to an embodiment, the STA may discover the AP through the first link, but may not discover the AP through the second link. The STA may transmit and receive data with the AP through the first link for a certain period of time.

B. Association process

B-i) The STA may perform the association process with the AP on the link on which the discovery process is performed.

The AP may restrict the association process to perform only a specific link (eg, the first link). The AP may transmit information about a link for performing the association process to the STA in the discovery process. The STA may perform the association process by changing the link after the discovery process.

B-ii) Information transmitted between the STA and the AP during the association process is as follows.

B-ii) -a) Information transmitted from AP to STA

-Information about a link (or band) for transmitting and receiving data after the association process by the STA: If the AP does not transmit information about a link (or band) for transmitting and receiving data to the STA, the link having formed the association process is Data. It can be a link for transmitting and receiving.

Information on Association ID of STA: The AP may manage the Association ID of the STA for each link.

B-ii) -b) Information transmitted from STA to AP

Information on the Capability of the STA: The information on the capability of the STA may indicate information on whether multi-link is supported by the STA.

Information on a Preferred Link of the STA: The STA may transmit information on a preferred link for transmitting and receiving data to the AP. The AP may determine a link for transmitting and receiving data with the STA based on the information on the preferred link of the STA.

Information about RSSI of each link: The STA may transmit information about RSSI of a frame received from the AP on each link to the AP. The AP may determine a link for transmitting and receiving data with the STA based on the information about the RSSI of each link.

B-iii) The STA may not support multilink. Therefore, the STA may perform transmission and reception of data through a link determined during the association process after the association process is completed without any additional process.

C. Data transmission and reception link (or band) signaling process

In the data transmission / reception link (or band) signaling process, the STA may transmit information about the second link to the AP through the first link. The information on the second link may include a Receive Signal Strength Indicator (RSSI) or a Signal to Interference plus Noise Ratio (SINR) of the second link. Hereinafter, a specific data transmission / reception link (or band) signaling process may be described.

C-i) Signal (or data) transmission and reception link signaling process may be included in the association process. The association process may be the process described in step B.

C-ii) Association process may not include the process of exchanging information about data transmission / reception link. In this case, since the data transmission / reception link of the STA has not been determined yet, the data transmission / reception link signaling process may be performed separately.

 C-iii) The AP or STA may determine the data transmission / reception link through various methods. For example, the AP or STA may exchange information for determining a data transmission / reception link. The AP or STA may determine the data transmission / reception link based on the exchange.

C-iv) Data transmission and reception link signaling process may be performed based on Request / Response.

C-iv) -a) STA or AP may transmit a request frame. The request frame may include information about a data transmission / reception link. For example, the request frame may include a link preferred by an STA or an AP and / or a received signal strength indicator (RSSI) or a signal to interference plus noise ratio (SINR) of each link.

C-iv) -b) STA may receive a request frame from the AP. The STA may transmit a response frame in response to the request frame. The response frame may include information about a data transmission / reception link. For example, the response frame may include a link preferred by an STA or an AP and / or a Receive Signal Strength Indicator (RSSI) or a Signal to Interference plus Noise Ratio (SINR) of each link.

C-iv) -c) When the data transmission / reception link signaling process is completed, the STA or AP may transmit / receive data through the established link.

C-iv) -d) Data transmission / reception link signaling process may be used when data transmission / reception link is changed.

27 to 30 below may illustrate specific examples of operations of an STA that does not support multi-link or an AP that supports multi-link.

27 shows an example of the operation of an STA that does not support multi-link.

Referring to FIG. 27, the AP may include a first AP 2701 or a second AP 2702. The first AP 2701 may support a first link (or first band). The second AP 2702 may support a second link (or second band). For example, the first link may comprise a link in the 2.4 GHz band. The second link may comprise a link within the 5 GHz band.

FIG. 27 may be a diagram in which an acknowledgment (ACK) frame for a frame is omitted. The AP may support multilink through the first AP 2701 and / or the second AP 2702. However, the STA 2710 may not support the multi link.

The STA 2710 may perform a discovery process through a first link (or first band). In detail, the STA 2710 may exchange a probe request / probe response frame with the first AP 2701. FIG. 27 illustrates an operation in which the STA 2710 discovers the first AP 2701 or the second AP 2702 through an active scanning process, but is not limited thereto. Although not shown, the STA 2710 may perform a passive scanning process by receiving a beacon (or beacon frame) from the first AP 2701 or the second AP 2702.

The STA 2710 may perform an association process with the first AP 2701 through the first link. In detail, the STA 2710 may exchange an association request / Association response frame with the first AP 2701. The STA 2710 may change the signal transmission link to the second link (or second band). The STA may transmit and receive downlink (DL) and / or uplink (UL) data with the first AP 2701 through the second link. The above-described process may be applied to the STA and / or AP of the 802.11ax standard.

In addition, the first AP 2701 may use the RSSI and / or SNIR values of the Probe request or Association request frame transmitted by the STA 2710 over the first link, and the current STA 2710 may be near the second AP 2702. You can see that it is located at. The first AP 2701 may determine that the STA 2710 is capable of transmitting and receiving data with the second AP 2702 through the second link. Accordingly, the first AP 2701 may allocate the second link to the STA 2710.

Conversely, the STA 2710 may determine that the current STA 2710 is also close to the second AP 2702 through the Beacon, Probe Response, or RSSI / SINR of the Association Response frame received from the first AP 2701. Can be. The STA 2710 may transmit to the first AP 2701 that the second link is preferred as a link for transmitting and receiving data. The first AP 2701 may determine a link for transmitting and receiving data based on the preferred link received from the STA 2710. The first AP 2701 may determine the second link as a link for transmitting and receiving data. Data transmission and reception link signaling process may be included in the Association. The STA 2710 adjusts the sync of the second link for transmitting and receiving data with the first AP 2701 through a data transmission / reception link signaling process, or information about the quality of the first link or the second link (for example, RSSI or SINR) may be exchanged.

28 shows another example of an operation of an STA that does not support multilink.

Referring to FIG. 28, the STA 2810 may perform a discovery process through the first link. The STA 2810 may also perform a discovery process through the second link. The STA 2810 may discover the first AP 2801 and the second AP 2802 through a discovery process. The STA 2810 may confirm that the first AP 2801 or the second AP 2802 is included in the AP. The STA 2810 may confirm that data may be transmitted and received with the AP through the first link or the second link.

The STA 2810 may determine / select a link for transmitting and receiving data with the first AP 2801 through an association process. For example, the STA 2810 may obtain information such as RSSI / SINR of a Beacon, Probe Response, or Association Response frame received from the first AP 2801. The STA 2810 may acquire information such as RSSI / SINR of a Beacon or Probe Response frame received from the second AP 2802. The STA 2810 may determine / select a link for transmitting and receiving data based on the obtained information about the signal quality. The STA 2810 may determine / select a second link as a link for transmitting and receiving data with the first AP 2801 through an association process. The association process shown in FIG. 28 may relate to the association process of FIG. 27.

The STA 2810 may transmit / receive UL and / or DL data with the AP through the second link after the association process.

29 illustrates another example of an operation of an STA that does not support multilink.

Referring to FIG. 29, the STA 2910 may perform a discovery process on a first link (or first band). The STA may also perform a discovery process on the second link (or the second band). The STA 2910 may discover the first AP 2901 over the first link. The STA may not discover the second AP 2902 over the second link. In more detail, the STA 2910 may transmit a probe request frame through the first link and the second link. The STA 2910 may receive a probe response frame through the first link from the first AP 2901. The STA 2910 may not receive a probe response frame from the second AP 2902 over the second link.

Since the STA 2910 discovers only the first AP 2901, the STA 2910 may perform an association process with the first AP 2901 through the first link. After the association process is completed, the STA 2910 may transmit and receive UL or DL data with the first AP 2901 through the first link.

30 shows another example of an operation of an STA that does not support multi-link.

FIG. 30 illustrates an embodiment in which a data transmission / reception link signaling process is separated from an association process in the embodiment illustrated in FIG. 28.

Referring to FIG. 30, the STA 3010 may discover the first AP 3001 or the second AP 3002 through a discovery process. The STA 3010 may perform an association process with the first AP 3002.

After the Association process is completed, the STA 3010 may perform a data transmission / reception link signaling process. The STA 3010 or the first AP 3001 may perform a data transmission / reception link signaling process to determine a link for transmitting and receiving data. In detail, the STA 3010 may transmit a Data Band request frame to the first AP 3001. The STA 3010 may receive a data band response frame from the first AP 3001. FIG. 30 illustrates an operation of transmitting a data band request frame from the STA 3010 and receiving a data band response frame from the first AP 3001 from the first AP 3001, but is not limited thereto. According to an embodiment, the first AP 3001 may transmit a data band request frame and receive a data band response frame from the STA 3010.

The data band request frame or the data band response frame may include information about a link for transmitting and receiving data. For example, the STA 3010 may provide information on whether to transmit / receive data with the first AP 3001 through the first link or whether to transmit / receive data with the second AP 3002 through the second link. The data band request frame may be transmitted to the first AP 3001.

The data band request frame or the data band response frame may include information about channel quality of the first link or the second link. For example, the STA 3010 may transmit information related to the RSSI or SINR of the first link and / or information related to the RSSI or SINR of the second link to the first AP 3001 through a data band request frame. .

The STA 3010 and the first AP 3001 may determine a link for transmitting and receiving data as a second link through a data transmission / reception link signaling process. The STA may transmit / receive UL data or DL data with the second AP 3002 through the second link.

31 is a flowchart for explaining an example of an operation of an STA that does not support multi-link.

Referring to FIG. 31, in step S3110, an STA (eg, the STA 3010) may perform a discovery process through a first link. The STA may support the first link and the second link.

According to an embodiment of the present disclosure, the STA performs an access point (AP) including an access point (eg, an AP including the first AP 3001 and the second AP 3002) and a probe request frame or a probe response frame through the first link. I can exchange it. The STA may discover the AP by exchanging a probe request frame or probe response frame.

According to an embodiment, the STA may receive a beacon from the AP through the first link. The STA may discover the AP based on the beacon.

In step S3120, the STA may perform a discovery process through the second link. The STA may perform the discovery process on the second link similarly to the discovery process performed on the first link.

In step S3130, the STA may perform an association process with an access point (AP) through the first link. Through the association process, the STA may receive information on a link for transmitting and receiving data or information on an association ID of the STA from the AP. Through the association process, the STA may transmit information on the capability of the STA, information on the preferred link of the STA, or information on the RSSI of each link to the AP.

In step S3140, the STA may transmit information about the second link to the AP through the first link. The information on the second link may include a Receive Signal Strength Indicator (RSSI) or a Signal to Interference plus Noise Ratio (SINR) of the second link. The STA may transmit the information on the link that the STA prefers for communication with the AP together with the information on the second link. The STA may transmit information about the second link to the AP through a data band request frame. The STA may receive a data band response frame from the AP in response to the data band request frame.

In step S3150, the STA may perform a second communication with the AP through the second link. The second communication can mean communication via a second link. The first communication may mean communication through the first link. The STA may transmit UL data to the AP. The STA may receive DL data from the AP.

Thereafter, the STA may transmit the information about the first link to the AP through the second link. The information about the first link may include a Receive Signal Strength Indicator (RSSI) or a Signal to Interference plus Noise Ratio (SINR) of the first link. The STA may transmit the information on the link that the STA prefers for communication with the AP together with the information on the first link. The STA may change the link for communicating with the AP from the second link to the first link. The STA may perform first communication with the AP via the first link.

32 is a flowchart illustrating an example of an operation of an AP connected to an STA that does not support multi-link.

Referring to FIG. 32, in step S3210, an access point (AP) (eg, an AP including the first AP 3001 and the second AP 3002) may perform a discovery process through a first link. Can be done. The AP may support multiple links including a first link and a second link.

According to an embodiment of the present disclosure, the AP may exchange a probe request frame or a probe response frame with an STA (for example, the STA 3010) through the first link. The AP may discover the STA by exchanging a probe request frame or a probe response frame.

According to an embodiment, the AP may transmit a beacon through the first link. The AP may discover the STA based on the beacon.

In step S3220, the AP may perform a discovery process through the second link. The AP may perform the discovery process on the second link similarly to the discovery process performed on the first link.

In step S3230, the AP may perform an association process with the STA through the first link. Through the association process, the AP may transmit information on a link for transmitting and receiving data or information on an association ID of the STA to the STA. Through the association process, the AP may receive information on the capability of the STA, information on the preferred link of the STA, or information on the RSSI of each link from the STA.

In step S3240, the STA may receive information on the second link from the STA through the first link. The AP may receive information about the second link through the first link from the STA. The information on the second link may include a Receive Signal Strength Indicator (RSSI) or a Signal to Interference plus Noise Ratio (SINR) of the second link. The AP may receive information regarding the link that the STA prefers for communication with the AP together with the information about the second link.

In addition, the AP may transmit information about the second link and / or information about a link that the AP prefers for communication with the STA.

The AP may receive information about the second link from the STA through a data band request frame. The AP may transmit a data band response frame to the STA in response to the data band request frame.

In step S3250, the AP may perform a second communication with the STA through the second link. The AP may receive UL data from the STA. The AP may transmit DL data to the STA.

2. In case of STA supporting multi-link (or multi-band)

The STA supporting the multi link may perform a discovery process through the first link. Thereafter, the STA may perform an association process with the AP through the first link. The STA may transmit information about the multi link to the AP through the first link. The STA may communicate with the AP via a multilink including a first link and a second link.

The operation of the STA supporting the multi-link may be described through the following steps D to F. In the following, detailed description of the steps D to F may be described below.

D. Discovery Process

D-i) When the STA supports the multi-link, the STA may perform a scanning process on one link or the multi-link among the multi-links in which the AP operates. For example, the AP may operate in the first band (2.4 GHz band) and the second band (5 GHz band). The AP may include a first AP supporting the first band or a second AP supporting the second band.

The STA may receive a beacon (or beacon frame) transmitted by the AP. The STA may discover an AP through the beacon. The STA may discover the AP by transmitting and receiving a Probe Request frame / Probe Response frame with the AP.

However, the STA may not be able to transmit a signal through the multi link during the discovery process. In this case, the STA may perform only reception of a signal through the multi link.

D-ii) Even if the AP supports multiple links, the AP may perform a discovery process through one link. For example, the AP may transmit a beacon (or beacon frame) only on one link. For another example, the AP may respond to a Probe Request frame only on a specific link.

D-iii) The STA may know that the AP supports multilink. Through the above-described first embodiment, the STA may confirm that the AP supports multilink.

D-iv) The STA may transmit / receive data in a state of being currently associated with an AP by using a multi-link function. At the same time, the STA may perform a scanning process to discover another AP of another link. For example, the STA may include two RFs (or RF units). The STA may maintain an association with the first AP through one RF in the first link (or the first band). While maintaining the association with the first AP, the STA may perform a scanning process to discover another AP (eg, the second AP) through the second link through the remaining RF. In the case of performing the association process and the discovery process at the same time, the STA may quickly discover nearby unassociated APs while transmitting and receiving data with the associated AP. Accordingly, the STA may perform handover quickly.

E. Association Process

E-i) The STA may acquire link (or band) information of the AP through a discovery process. The STA may perform an association process with the AP based on the obtained information.

E-i) -a) The STA may perform the association process with the AP on the link on which the discovery process is performed.

E-i) -b) The AP may designate a specific link to perform only a specific link in the association process. The STA may perform an association process with the AP through a specific link designated by the AP.

E-i) -c) The STA may perform an association process with the AP through one link of the multi-links.

E-ii) The information transmitted between the STA and the AP during the association process is as follows.

E-ii) -a) Information transmitted from AP to STA

Multi-link information: STA may obtain the multi-link information from the AP through the discovery process. However, during the association process, multi-link information may be added or changed. In this case, the AP may transmit multilink information to the STA again. Parameters related to Channel Access may be changed in each link (or band).

Association ID of STA: The AP may manage Association ID for each link.

E-ii) -b) Information transmitted from STA to AP

Information on the Capability of the STA: The information on the capability of the STA may indicate information on whether multi-link is supported by the STA. Additionally, the information about the capability of the STA may indicate whether the STA operates synchronously or asynchronously in a situation in which the STA operates in a multi-link.

For example, a STA that operates synchronously may only transmit or receive at a specific time.

For another example, an STA operating in asynchronous manner may transmit a signal through a first RF included in the STA. At the same time, the STA operating in asynchronous manner may receive a signal through a second RF included in the STA. Therefore, an STA operating in asynchronous manner can operate individually for each link without having to match transmission and reception for each link.

E-iii) Even if the STA supports the multi-link, the STA may perform data transmission through the multi-link after setting up the multi-link transmission with the AP. Therefore, Discovery, Authentication, Association, etc. can be performed in one link. Thereafter, the STA or the AP may perform data transmission and reception through the multilink through additional signaling.

F. Multi-Link Signaling Process

F-i) The multi-link signaling process may be included in the association process. For example, the STA may transmit information indicating whether multi-link transmission is possible after the above-described Association process is performed. Information that multi-link transmission is possible may be transmitted from the STA to the AP. In this case, the STA and / or AP may perform data transmission and reception through the multi link after the association process is completed.

 F-ii) However, information indicating that multilink transmission is not possible may be transmitted from the STA to the AP. After the signaling process is performed, the STA and the AP may perform data transmission and reception through the multilink.

F-iii) Multi-link signaling process may be performed based on Request / Response.

F-iii) -a) STA or AP may transmit a multi-link request frame. The multilink request frame may include information about multilink. For example, the multi-link request frame may include information about transmission power, MCS, center frequency of the multi-link, and the like.

F-iii) -b) STA may receive a multi-link request frame from the AP. The STA may transmit the multilink response frame in response to the multilink request frame. The multilink response frame may include information about data multilink. For example, the multi-link response frame may include information about the transmission power of the multi-link, the MCS, the center frequency.

F-iii) -c) When the multi-link signaling process is completed, the STA or AP may transmit and receive data through the multi-link.

33 to 35 may illustrate specific examples of operations of the STA supporting the multi-link or the AP supporting the multi-link described above.

33 illustrates an example of an operation of a STA that supports multilink.

Referring to FIG. 33, an AP may include a first AP 3301 or a second AP 3302. The first AP 3301 may support a first link (or first band). The second AP 3302 may support a second link (or second band). For example, the first link may comprise a link in the 2.4 GHz band. The second link may comprise a link within the 5 GHz band.

FIG. 33 may be a diagram in which an acknowledgment (ACK) frame for a frame is omitted. The AP may support multilink through the first AP 3301 and / or the second AP 3302. The STA 3310 may support multilink.

The STA 3310 may perform a discovery process through a first link (or first band). In detail, the STA 3310 may perform a probe request / probe response frame exchange with the first AP 3301. 33 illustrates an operation in which the STA 3310 discovers the first AP 3301 or the second AP 3302 through an active scanning process, but is not limited thereto. Although not shown, the STA 3310 may perform a passive scanning process by receiving a beacon (or beacon frame) from the first AP 3301 or the second AP 3302.

The STA 3310 may perform an association process with the first AP 3301 through the first link. In detail, the STA 3310 may perform an association request / association response frame exchange with the first AP 3301. According to an embodiment, the STA 3310 may perform an association process with the second AP 3302 also through the second link.

The STA 3310 may transmit information regarding the capability of the STA 3310 to the first AP 3301 through the association process. The first AP 3301 may transmit multi-link information or information about an association ID of the STA 3310 to the STA 3310.

Association process may include a multi-link signaling process. In this case, the STA 3310 may complete preparation for transmitting and receiving data through the multi link through the association process. The STA 3310 may immediately transmit and receive DL data or UL data with an AP (the first AP 3301 or the second AP 3302) through a multi-link including a first link or a second link. .

34 shows another example of an operation of an STA supporting multilink.

Referring to FIG. 34, the STA 3410 may perform a discovery process through a first link (or first band). The STA 3410 may perform an association process with the first AP 3301 through the first link. The STA 3410 may transmit and receive DL data or UL data with the first AP 3301 through the first link.

The STA 3410 may perform a multilink signaling process through the first link. The STA 3410 may transmit a multilink request frame to the first AP 3401. The STA 3410 may receive a multilink response frame from the first AP 3401 in response to the multilink request frame.

The multilink request frame or the multilink response frame may include information on multilink. For example, the multi link request frame or the multi link response frame may include a transmission power of the multi link, an MCS, a center frequency, and the like.

After the multi-link signaling process is completed, the STA 3410 may perform DL data or UL data with the AP (the first AP 3401 or the second AP 3402) through the multi-link including the first link and the second link. Can send and receive

35 shows another example of an operation of an STA supporting multilink.

Referring to FIG. 35, the STA 3510 may perform a discovery process through a first link (or first band). In detail, the STA 3510 may perform a passive scanning process by receiving a beacon (or beacon frame) from the first AP 3501 or the second AP 3502.

According to an embodiment, the STA 3510 may receive a beacon from the first AP 3501 or the second AP 3502 and perform an association process through one link of the first link or the second link. .

According to an embodiment, the STA 3510 receives a beacon from the first AP 3501 or the second AP 3502 and performs a link designated by the AP (the first AP 3501 or the second AP 3502). Association process can be performed through For example, the STA 3510 may discover the first AP 3501 or the second AP 3502 based on the beacon. The STA 3510 may obtain information from the AP (the first AP 3501 or the second AP 3502) that it will perform an association process over the first link. The STA 3510 may perform an association process with the first AP 3501 through the first link.

The operation process of the STA 3510 after the association process may be performed in the same manner as the operation process of the STA 3410 after the association illustrated in FIG. 34.

36 is a flowchart illustrating an example of an operation of an STA that supports multilink.

Referring to FIG. 36, in step S3610, an STA (eg, the STA 3410) may perform a discovery process through a first link. The STA may support multilink including a first link and a second link. Through the discovery process, the STA may discover an AP (eg, an AP including the first AP 3401 and the second AP 3402). The STA may confirm that the AP supports multilink.

According to an embodiment, the STA may exchange a probe request frame or a probe response frame with an access point (AP) through a first link. The STA may discover the AP by exchanging a probe request frame or probe response frame.

According to an embodiment, the STA may receive a beacon from the AP through the first link. The STA may discover the AP based on the beacon.

In step S3620, the STA may perform an association process with an access point (AP) through the first link. Through the association process, the STA may receive information on the multi-link or the information on the association ID of the STA from the AP. Through the association process, the STA may transmit information regarding the capability of the STA to the AP.

In step S3630, the STA may transmit information about the multi link to the AP through the first link.

The STA may transmit information indicating whether multilink transmission is possible after the association procedure is performed. That is, the information about the multi-link may include information indicating whether multi-link transmission is possible after the association process is performed. In addition, the information on the multi-link may include information on the transmission power of the multi-link, MCS, Center frequency and the like.

According to an embodiment, the STA may receive information about the multi link from the AP through the first link.

In step S3640, the STA may perform communication with the AP through a multi-link including a first link and a second link. The STA may transmit and receive DL data or UL data with the AP through a multi-link including the first link and the second link. The STA may transmit UL data to the AP. The STA may receive DL data from the AP.

FIG. 37 is a flowchart illustrating an example of an operation of an AP connected to an STA supporting multilink.

Referring to FIG. 37, in operation S3710, the AP (eg, the first AP 3401 and the second AP 3402 may perform a discovery process through a first link. It is possible to support multi-link including a link 1 and a link 2. The discovery process may enable the AP to discover an STA (eg, STA 3410) The AP confirms that the STA supports multi-link. Can be.

According to an embodiment, the AP may exchange a probe request frame or probe response frame with the STA through the first link. The AP may discover the STA by exchanging a probe request frame or a probe response frame.

According to an embodiment, the AP may transmit a beacon through the first link. The AP may discover the STA based on the beacon.

In step S3720, the AP may perform an association process with the STA through the first link. Through the association process, the AP may transmit information about the multi link or information about the association ID of the STA to the STA. Through the association process, the AP may receive information on the capability of the STA from the STA.

In operation S3730, the AP may receive information regarding the multi link from the STA through the first link.

After the association process is performed, the AP may receive information indicating whether multi-link transmission is possible from the STA. That is, the information about the multi-link may include information indicating whether multi-link transmission is possible after the association process is performed. In addition, the information on the multi-link may include information on the transmission power of the multi-link, the MCS, the center frequency.

According to an embodiment, the AP may transmit information about the multi link to the STA through the first link.

In step S3740, the AP may communicate with the STA through a multi-link including a first link and a second link. The AP may transmit and receive DL data or UL data with the STA through a multi-link including the first link and the second link. The AP may receive UL data from the STA. The AP may transmit DL data to the STA.

38 illustrates an AP or STA to which an example of the present specification is applied.

Referring to FIG. 38, the STA 3800 may include a processor 3810, a memory 3820, and a transceiver 3830. 38 may be applied to a non-AP STA or an AP STA. The illustrated processor, memory, and transceiver may be implemented as separate chips, or at least two blocks / functions may be implemented through one chip.

The illustrated transceiver 3830 performs transmission and reception of signals. Specifically, it is possible to transmit and receive IEEE 802.11 packets (for example, IEEE 802.11a / b / g / n / ac / ax / be, etc.).

The processor 3810 may implement the functions, processes, and / or methods proposed herein. In detail, the processor 3810 may receive a signal through the transceiver 3830, process the received signal, generate a transmission signal, and perform control for signal transmission.

The processor 3810 may include an application-specific integrated circuit (ASIC), another chipset, a logic circuit, and a data processing device. Memory 3820 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage devices.

The memory 3820 may store a signal received through the transceiver (ie, a received signal) and store a signal to be transmitted through the transceiver (ie, a transmitted signal). That is, the processor 3810 may acquire the received signal through the memory 3820 and store the signal to be transmitted in the memory 3820.

39 shows another example of a detailed block diagram of a transceiver. Some or all of the blocks of FIG. 39 may be included in the processor 3810. Referring to FIG. 39, the transceiver 3900 includes a transmitting part 3901 and a receiving part 3902. The transmission part 3901 includes a discrete fourier transform (DFT) unit 3911, a subcarrier mapper 3912, an IDFT / IFFT unit 3913, a CP insertion unit 3914, and a wireless transmitter 3915. The transmission part 3901 may further include a modulator. Also, for example, the apparatus may further include a scramble unit (not shown), a modulation mapper (not shown), a layer mapper (not shown) and a layer permutator (not shown). This may be disposed before the DFT unit 3911. That is, in order to prevent an increase in peak-to-average power ratio (PAPR), the transmission part 3901 first passes the information through the DFT unit 3911 before mapping a signal to a subcarrier. Subcarrier mapping of the signal spread by the DFT unit 3911 (or precoded with the same meaning) through the subcarrier mapper 3912, and then again through the IDFT / IFFT (Inverse Fast Fourier Transform) unit 3913 It is a signal on the time base.

The DFT unit 3911 outputs complex-valued symbols by performing a DFT on the input symbols. For example, when Ntx symbols are input (where Ntx is a natural number), the DFT size is Ntx. The DFT unit 3911 may be called a transform precoder. The subcarrier mapper 1912 maps the complex symbols to each subcarrier in the frequency domain. The complex symbols may be mapped to resource elements corresponding to resource blocks allocated for data transmission. The subcarrier mapper 3912 may be called a resource element mapper. The IDFT / IFFT unit 3913 performs IDFT / IFFT on the input symbol and outputs a baseband signal for data, which is a time domain signal. The CP inserting unit 3914 copies a part of the rear part of the baseband signal for data and inserts it into the front part of the baseband signal for data. Inter-symbol interference (ISI) and inter-carrier interference (ICI) can be prevented through CP insertion to maintain orthogonality even in multipath channels.

On the other hand, the receiving part 1902 includes a radio receiver 3921, a CP remover 3922, an FFT unit 3913, an equalizer 3924, and the like. The wireless receiving unit 3921, the CP removing unit 3922, and the FFT unit 3913 of the receiving part 3902 are the wireless transmitting unit 3915, the CP insertion unit 3914, and the IFF unit 3913 at the transmitting end 3901. It performs the reverse function of). The receiving part 1902 may further include a demodulator.

In addition to the illustrated block, the transceiver of FIG. 39 may include a reception window controller (not shown) for extracting a part of a received signal, and a decoding operation processor (not shown) for performing a decoding operation on a signal extracted through the reception window. ) May be included.

The technical features of the present specification described above can be applied to various applications or business models. For example, the above-described technical feature may be applied for wireless communication in an apparatus supporting artificial intelligence (AI).

Artificial intelligence refers to the field of researching artificial intelligence or the methodology that can produce it, and machine learning refers to the field of researching methodologies to define and solve various problems dealt with in the field of artificial intelligence. do. Machine learning is defined as an algorithm that improves the performance of a task through a consistent experience with a task.

Artificial Neural Network (ANN) is a model used in machine learning, and may refer to an overall problem-solving model composed of artificial neurons (nodes) that form a network by combining synapses. The artificial neural network may be defined by a connection pattern between neurons of different layers, a learning process of updating model parameters, and an activation function generating an output value.

The artificial neural network may include an input layer, an output layer, and optionally one or more hidden layers. Each layer contains one or more neurons, and the artificial neural network may include synapses that connect neurons to neurons. In an artificial neural network, each neuron may output a function value of an active function for input signals, weights, and deflections input through a synapse.

The model parameter refers to a parameter determined through learning and includes weights of synaptic connections and deflection of neurons. In addition, the hyperparameter means a parameter to be set before learning in the machine learning algorithm, and includes a learning rate, the number of iterations, a mini batch size, an initialization function, and the like.

The purpose of learning artificial neural networks can be seen as determining model parameters that minimize the loss function. The loss function can be used as an index for determining an optimal model parameter in the learning process of an artificial neural network.

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

Supervised learning refers to a method of learning artificial neural networks with a given label for training data, and a label indicates a correct answer (or result value) that the artificial neural network must infer when the training data is input to the artificial neural network. Can mean. Unsupervised learning may refer to a method of training artificial neural networks in a state where a label for training data is not given. Reinforcement learning can mean a learning method that allows an agent defined in an environment to learn to choose an action or sequence of actions that maximizes cumulative reward in each state.

Machine learning, which is implemented as a deep neural network (DNN) including a plurality of hidden layers among artificial neural networks, is called deep learning (Deep Learning), which is part of machine learning. Hereinafter, machine learning is used to mean deep learning.

In addition, the above-described technical features can be applied to the wireless communication of the robot.

A robot can mean a machine that automatically handles or operates a given task by its own ability. In particular, a robot having a function of recognizing the environment, judging itself, and performing an operation may be referred to as an intelligent robot.

Robots can be classified into industrial, medical, household, military, etc. according to the purpose or field of use. The robot may include a driving unit including an actuator or a motor to perform various physical operations such as moving a robot joint. In addition, the movable robot includes a wheel, a brake, a propeller, and the like in the driving unit, and can travel on the ground or fly in the air through the eastern part.

In addition, the above-described technical feature may be applied to an apparatus supporting extended reality.

Extended reality collectively refers to virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology provides real world objects and backgrounds only in CG images, AR technology provides virtual CG images on real objects images, and MR technology mixes and combines virtual objects in the real world. Graphic technology.

MR technology is similar to AR technology in that it shows both real and virtual objects. However, in AR technology, virtual objects are used as complementary objects to real objects, whereas in MR technology, virtual objects and real objects are used in an equivalent nature.

XR technology can be applied to HMD (Head-Mount Display), HUD (Head-Up Display), mobile phone, tablet PC, laptop, desktop, TV, digital signage, etc. It can be called.

Claims (14)

1. In a wireless local area network (WLAN),

   Performing, by the STA supporting the first link and the second link, a discovery process on the first link;

   Performing, by the STA, a discovery process on the second link;

   Performing, by the STA, an association process with an access point (AP) through the first link;

   Transmitting, by the STA, the information about the second link to the AP through the first link; And

   Performing, by the STA, a second communication with the AP through the second link;

   Containing

   Way.
2. According to claim 1,

   The information about the second link,

   And a Receive Signal Strength Indicator (RSSI) or Signal to Interference plus Noise Ratio (SINR) of the second link.
3. According to claim 1,

   Transmitting, by the STA, information about the first link to the AP through the second link;

   Changing, by the STA, a link for communicating with the AP from a second link to a first link; And

   The STA performing first communication with the AP via the first link

   Containing more

   Way.
4. According to claim 1,

   The performing of the discovery procedure by the STA through the first link may include:

   Exchanging, by the STA, a Probe request frame or a Probe response frame with the AP through the first link,

   Wherein the STA, performing the discovery (discovery) through the second link,

   Exchanging, by the STA, a Probe request frame or a Probe response frame with the AP through the second link;

   Containing

   Way.
5. According to claim 1,

   The performing of the discovery procedure by the STA through the first link may include:

   The STA receiving a beacon from the AP via the first link,

   Wherein the STA, performing the discovery (discovery) through the second link,

   The STA receiving a beacon from the AP via the second link

   Containing

   Way.
6. According to claim 1,

   Wherein the STA, performing a second communication with the AP via the second link,

   Receiving, by the STA, information for performing communication from the AP to the second link through the first link; And

   The STA performing a second communication with the AP via the second link

   Containing

   Way.
7. According to claim 1,

   The first link is received via a first band,

   The second link is received on a second band different from the first band,

   The first band or the second band is one of a 2.4 GHz band, a 5 GHz band, and / or a 6 GHz band.

   Way.
8. In a wireless local area network (STA) system, an STA supporting a first link and a second link,

   A transceiver for transmitting and receiving wireless signals; And

   Including a processor for controlling the transceiver,

   The processor,

   Perform a discovery procedure through the first link,

   Perform a discovery procedure via the second link,

   Performing an association process with an access point (AP) through the first link,

   Transmit information about the second link to the AP via the first link,

   The STA is configured to perform second communication with the AP via the second link.

   Device.
9. The method of claim 8, wherein the information about the second link includes:

   Receive Signal Strength Indicator (RSSI) or Signal to Interference plus Noise Ratio (SINR) of the second link

   Device.
10. The method of claim 8, wherein the processor,

    Via the second link, transmit information about the first link to the AP,

    Change a link for communicating with the AP from a second link to a first link,

    Further configured to perform a first communication with the AP via the first link

    Device.
11. The method of claim 8, wherein the processor,

    Configured to exchange a Probe request frame or Probe response frame with the AP through the first link,

    Configured to exchange a Probe request frame or a Probe response frame with the AP through the second link

    Device.
12. The method of claim 8, wherein the processor,

    Configured to receive a beacon from the AP over the first link,

    Configured to receive a beacon from the AP over the second link

    Device.
13. The method of claim 8, wherein the processor,

    Receive information for performing communication from the AP to the second link through the first link,

    Configured to perform a second communication with the AP via the second link

    Device.
14. The method of claim 8,

    The first link is received via a first band,

    The second link is received on a second band different from the first band,

    The first band or the second band is one of a 2.4 GHz band, a 5 GHz band, and / or a 6 GHz band.

    Device.

Images