Patent ID: 12250588

DETAILED DESCRIPTION

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

A slash (/) or comma used in the present specification may mean “and/or”. For example, “A/B” may mean “A and/or B”. Accordingly, “A/B” may mean “only A”, “only B”, or “both A and B”. For example, “A, B, C” may mean “A, B, or C”.

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

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

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

Technical features described individually in one figure in the present specification may be individually implemented, or may be simultaneously implemented.

The following example of the present specification may 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 also be applied to the newly proposed EHT standard or IEEE 802.11be standard. In addition, the example of the present specification may also be applied to a new WLAN standard enhanced from the EHT standard or the IEEE 802.11be standard. In addition, the example of the present specification may be applied to a mobile communication system. For example, it may be applied to a mobile communication system based on long term evolution (LTE) depending on a 3rdgeneration partnership project (3GPP) standard and based on evolution of the LTE. In addition, the example of the present specification may be applied to a communication system of a 5G NR standard based on the 3GPP standard.

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

FIG.1shows an example of a transmitting apparatus and/or receiving apparatus of the present specification.

In the example ofFIG.1, various technical features described below may be performed.FIG.1relates to at least one station (STA). For example, STAs110and120of the present specification may also be called in various terms such as a mobile terminal, a wireless device, a wireless transmit/receive unit (WTRU), a user equipment (UE), a mobile station (MS), a mobile subscriber unit, or simply a user. The STAs110and120of the present specification may also be called in various terms such as a network, a base station, a node-B, an access point (AP), a repeater, a router, a relay, or the like. The STAs110and120of the present specification may also be referred to as various names such as a receiving apparatus, a transmitting apparatus, a receiving STA, a transmitting STA, a receiving device, a transmitting device, or the like.

For example, the STAs110and120may serve as an AP or a non-AP. That is, the STAs110and120of the present specification may serve as the AP and/or the non-AP.

The STAs110and120of the present specification may support various communication standards together in addition to the IEEE 802.11 standard. For example, a communication standard (e.g., LTE, LTE-A, 5G NR standard) or the like based on the 3GPP standard may be supported. In addition, the STA of the present specification may be implemented as various devices such as a mobile phone, a vehicle, a personal computer, or the like. In addition, the STA of the present specification may support communication for various communication services such as voice calls, video calls, data communication, and self-driving (autonomous-driving), or the like.

The STAs110and120of the present specification may include a medium access control (MAC) conforming to the IEEE 802.11 standard and a physical layer interface for a radio medium.

The STAs110and120will be described below with reference to a sub-figure (a) ofFIG.1.

The first STA110may include a processor111, a memory112, and a transceiver113. The illustrated process, memory, and transceiver may be implemented individually as separate chips, or at least two blocks/functions may be implemented through a single chip.

The transceiver113of the first STA performs a signal transmission/reception operation. Specifically, an IEEE 802.11 packet (e.g., IEEE 802.11a/b/g/n/ac/ax/be, etc.) may be transmitted/received.

For example, the first STA110may perform an operation intended by an AP. For example, the processor111of the AP may receive a signal through the transceiver113, process a reception (RX) signal, generate a transmission (TX) signal, and provide control for signal transmission. The memory112of the AP may store a signal (e.g., RX signal) received through the transceiver113, and may store a signal (e.g., TX signal) to be transmitted through the transceiver.

For example, the second STA120may perform an operation intended by a non-AP STA. For example, a transceiver123of a non-AP performs a signal transmission/reception operation. Specifically, an IEEE 802.11 packet (e.g., IEEE 802.11a/b/g/n/ac/ax/be packet, etc.) may be transmitted/received.

For example, a processor121of the non-AP STA may receive a signal through the transceiver123, process an RX signal, generate a TX signal, and provide control for signal transmission. A memory122of the non-AP STA may store a signal (e.g., RX signal) received through the transceiver123, and may store a signal (e.g., TX signal) to be transmitted through the transceiver.

For example, an operation of a device indicated as an AP in the specification described below may be performed in the first STA110or the second STA120. For example, if the first STA110is the AP, the operation of the device indicated as the AP may be controlled by the processor111of the first STA110, and a related signal may be transmitted or received through the transceiver113controlled by the processor111of the first STA110. In addition, control information related to the operation of the AP or a TX/RX signal of the AP may be stored in the memory112of the first STA110. In addition, if the second STA120is the AP, the operation of the device indicated as the AP may be controlled by the processor121of the second STA120, and a related signal may be transmitted or received through the transceiver123controlled by the processor121of the second STA120. In addition, control information related to the operation of the AP or a TX/RX signal of the AP may be stored in the memory122of the second STA120.

For example, in the specification described below, an operation of a device indicated as a non-AP (or user-STA) may be performed in the first STA110or the second STA120. For example, if the second STA120is the non-AP, the operation of the device indicated as the non-AP may be controlled by the processor121of the second STA120, and a related signal may be transmitted or received through the transceiver123controlled by the processor121of the second STA120. In addition, control information related to the operation of the non-AP or a TX/RX signal of the non-AP may be stored in the memory122of the second STA120. For example, if the first STA110is the non-AP, the operation of the device indicated as the non-AP may be controlled by the processor111of the first STA110, and a related signal may be transmitted or received through the transceiver113controlled by the processor111of the first STA110. In addition, control information related to the operation of the non-AP or a TX/RX signal of the non-AP may be stored in the memory112of the first STA110.

In the specification described below, a device called a (transmitting/receiving) STA, a first STA, a second STA, a STA1, a STA2, an AP, a first AP, a second AP, an AP1, an AP2, a (transmitting/receiving) terminal, a (transmitting/receiving) device, a (transmitting/receiving) apparatus, a network, or the like may imply the STAs110and120ofFIG.1. For example, a device indicated as, without a specific reference numeral, the (transmitting/receiving) STA, the first STA, the second STA, the STA1, the STA2, the AP, the first AP, the second AP, the AP1, the AP2, the (transmitting/receiving) terminal, the (transmitting/receiving) device, the (transmitting/receiving) apparatus, the network, or the like may imply the STAs110and120ofFIG.1. For example, in the following example, an operation in which various STAs transmit/receive a signal (e.g., a PPDU) may be performed in the transceivers113and123ofFIG.1. In addition, in the following example, an operation in which various STAs generate a TX/RX signal or perform data processing and computation in advance for the TX/RX signal may be performed in the processors111and121ofFIG.1. For example, an example of an operation for generating the TX/RX signal or performing the data processing and computation in advance may include: 1) an operation of determining/obtaining/configuring/computing/decoding/encoding bit information of a sub-field (SIG, STF, LTF, Data) included in a PPDU; 2) an operation of determining/configuring/obtaining a time resource or frequency resource (e.g., a subcarrier resource) or the like used for the sub-field (SIG, STF, LTF, Data) included the PPDU; 3) an operation of determining/configuring/obtaining a specific sequence (e.g., a pilot sequence, an STF/LTF sequence, an extra sequence applied to SIG) or the like used for the sub-field (SIG, STF, LTF, Data) field included in the PPDU; 4) a power control operation and/or power saving operation applied for the STA; and 5) an operation related to determining/obtaining/configuring/decoding/encoding or the like of an ACK signal. In addition, in the following example, a variety of information used by various STAs for determining/obtaining/configuring/computing/decoding/decoding a TX/RX signal (e.g., information related to a field/subfield/control field/parameter/power or the like) may be stored in the memories112and122ofFIG.1.

The aforementioned device/STA of the sub-figure (a) ofFIG.1may be modified as shown in the sub-figure (b) ofFIG.1. Hereinafter, the STAs110and120of the present specification will be described based on the sub-figure (b) ofFIG.1.

For example, the transceivers113and123illustrated in the sub-figure (b) ofFIG.1may perform the same function as the aforementioned transceiver illustrated in the sub-figure (a) ofFIG.1. For example, processing chips114and124illustrated in the sub-figure (b) ofFIG.1may include the processors111and121and the memories112and122. The processors111and121and memories112and122illustrated in the sub-figure (b) ofFIG.1may perform the same function as the aforementioned processors111and121and memories112and122illustrated in the sub-figure (a) ofFIG.1.

A mobile terminal, a wireless device, a wireless transmit/receive unit (WTRU), a user equipment (UE), a mobile station (MS), a mobile subscriber unit, a user, a user STA, a network, a base station, a Node-B, an access point (AP), a repeater, a router, a relay, a receiving unit, a transmitting unit, a receiving STA, a transmitting STA, a receiving device, a transmitting device, a receiving apparatus, and/or a transmitting apparatus, which are described below, may imply the STAs110and120illustrated in the sub-figure (a)/(b) ofFIG.1, or may imply the processing chips114and124illustrated in the sub-figure (b) ofFIG.1. That is, a technical feature of the present specification may be performed in the STAs110and120illustrated in the sub-figure (a)/(b) ofFIG.1, or may be performed only in the processing chips114and124illustrated in the sub-figure (b) ofFIG.1. For example, a technical feature in which the transmitting STA transmits a control signal may be understood as a technical feature in which a control signal generated in the processors111and121illustrated in the sub-figure (a)/(b) ofFIG.1is transmitted through the transceivers113and123illustrated in the sub-figure (a)/(b) ofFIG.1. Alternatively, the technical feature in which the transmitting STA transmits the control signal may be understood as a technical feature in which the control signal to be transferred to the transceivers113and123is generated in the processing chips114and124illustrated in the sub-figure (b) ofFIG.1.

For example, a technical feature in which the receiving STA receives the control signal may be understood as a technical feature in which the control signal is received by means of the transceivers113and123illustrated in the sub-figure (a) ofFIG.1. Alternatively, the technical feature in which the receiving STA receives the control signal may be understood as the technical feature in which the control signal received in the transceivers113and123illustrated in the sub-figure (a) ofFIG.1is obtained by the processors111and121illustrated in the sub-figure (a) ofFIG.1. Alternatively, the technical feature in which the receiving STA receives the control signal may be understood as the technical feature in which the control signal received in the transceivers113and123illustrated in the sub-figure (b) ofFIG.1is obtained by the processing chips114and124illustrated in the sub-figure (b) ofFIG.1.

Referring to the sub-figure (b) ofFIG.1, software codes115and125may be included in the memories112and122. The software codes115and126may include instructions for controlling an operation of the processors111and121. The software codes115and125may be included as various programming languages.

The processors111and121or processing chips114and124ofFIG.1may include an application-specific integrated circuit (ASIC), other chipsets, a logic circuit and/or a data processing device. The processor may be an application processor (AP). For example, the processors111and121or processing chips114and124ofFIG.1may include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), and a modulator and demodulator (modem). For example, the processors111and121or processing chips114and124ofFIG.1may be SNAPDRAGON™ series of processors made by Qualcomm®, EXYNOS™ series of processors made by Samsung®, A series of processors made by Apple®, HELIO™ series of processors made by MediaTek®, ATOM™ series of processors made by Intel® or processors enhanced from these processors.

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

FIG.2is a conceptual view illustrating the structure of a wireless local area network (WLAN).

An upper part ofFIG.2illustrates the structure of an infrastructure basic service set (BSS) of institute of electrical and electronic engineers (IEEE) 802.11.

Referring the upper part ofFIG.2, the wireless LAN system may include one or more infrastructure BSSs200and205(hereinafter, referred to as BSS). The BSSs200and205as a set of an AP and a STA such as an access point (AP)225and a station (STA1)200-1which are successfully synchronized to communicate with each other are not concepts indicating a specific region. The BSS205may include one or more STAs205-1and205-2which may be joined to one AP230.

The BSS may include at least one STA, APs providing a distribution service, and a distribution system (DS)210connecting multiple APs.

The distribution system210may implement an extended service set (ESS)240extended by connecting the multiple BSSs200and205. The ESS240may be used as a term indicating one network configured by connecting one or more APs225or230through the distribution system210. The AP included in one ESS240may have the same service set identification (SSID).

A portal220may serve as a bridge which connects the wireless LAN network (IEEE 802.11) and another network (e.g., 802.X).

In the BSS illustrated in the upper part ofFIG.2, a network between the APs225and230and a network between the APs225and230and the STAs200-1,205-1, and205-2may be implemented. However, the network is configured even between the STAs without the APs225and230to perform communication. A network in which the communication is performed by configuring the network even between the STAs without the APs225and230is defined as an Ad-Hoc network or an independent basic service set (IBSS).

A lower part ofFIG.2illustrates a conceptual view illustrating the IBSS.

Referring to the lower part ofFIG.2, the IBSS is a BSS that operates in an Ad-Hoc mode. Since the IBSS does not include the access point (AP), a centralized management entity that performs a management function at the center does not exist. That is, in the IBSS, STAs250-1,250-2,250-3,255-4, and255-5are managed by a distributed manner. In the IBSS, all STAs250-1,250-2,250-3,255-4, and255-5may be constituted by movable STAs and are not permitted to access the DS to constitute a self-contained network.

FIG.3illustrates a general link setup process.

In S310, a STA may perform a network discovery operation. The network discovery operation may include a scanning operation of the STA. That is, to access a network, the STA needs to discover a participating network. The STA needs to identify a compatible network before participating in a wireless network, and a process of identifying a network present in a particular area is referred to as scanning. Scanning methods include active scanning and passive scanning.

FIG.3illustrates a network discovery operation including active scanning process. In active scanning, a STA performing scanning transmits a probe request frame and waits for a response to the probe request frame in order to identify which AP is present around while moving to channels. A responder transmits a probe response frame as a response to the probe request frame to the STA having transmitted the probe request frame. Here, the responder may be a STA that transmits the last beacon frame in a BSS of a channel being scanned. In the BSS, since an AP transmits a beacon frame, the AP is the responder. In an IBSS, since STAs in the IBSS transmit a beacon frame in turns, the responder is not fixed. For example, when the STA transmits a probe request frame via channel1and receives a probe response frame via channel1, the STA may store BSS-related information included in the received probe response frame, may move to the next channel (e.g., channel2), and may perform scanning (e.g., transmits a probe request and receives a probe response via channel2) by the same method.

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

After discovering the network, the STA may perform an authentication process in S320. The authentication process may be referred to as a first authentication process to be clearly distinguished from the following security setup operation in S340. The authentication process in S320may include a process in which the STA transmits an authentication request frame to the AP and the AP transmits an authentication response frame to the STA in response. The authentication frames used for an authentication request/response are management frames.

The authentication frames may include information related to an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a robust security network (RSN), and a finite cyclic group.

The STA may transmit the authentication request frame to the AP. The AP may determine whether to allow the authentication of the STA based on the information included in the received authentication request frame. The AP may provide the authentication processing result to the STA via the authentication response frame.

When the STA is successfully authenticated, the STA may perform an association process in S330. The association process includes a process in which the STA transmits an association request frame to the AP and the AP transmits an association response frame to the STA in response. The association request frame may include, for example, information related to various capabilities, a beacon listen interval, a service set identifier (SSID), a supported rate, a supported channel, RSN, a mobility domain, a supported operating class, a traffic indication map (TIM) broadcast request, and an interworking service capability. The association response frame may include, for example, information related to various capabilities, a status code, an association ID (AID), a supported rate, an enhanced distributed channel access (EDCA) parameter set, a received channel power indicator (RCPI), a received signal-to-noise indicator (RSNI), a mobility domain, a timeout interval (association comeback time), an overlapping BSS scanning parameter, a TIM broadcast response, and a QoS map.

In S340, the STA may perform a security setup process. The security setup process in S340may include a process of setting up a private key through four-way handshaking, for example, through an extensible authentication protocol over LAN (EAPOL) frame.

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

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

FIG.4also includes an example of an HE PPDU according to IEEE 802.11ax. The HE PPDU according toFIG.4is an illustrative PPDU for multiple users. An HE-SIG-B may be included only in a PPDU for multiple users, and an HE-SIG-B may be omitted in a PPDU for a single user.

As illustrated inFIG.4, the HE-PPDU for multiple users (MUs) may include a legacy-short training field (L-STF), a legacy-long training field (L-LTF), a legacy-signal (L-SIG), a high efficiency-signal A (HE-SIG A), a high efficiency-signal-B (HE-SIG B), a high efficiency-short training field (HE-STF), a high efficiency-long training field (HE-LTF), a data field (alternatively, an MAC payload), and a packet extension (PE) field. The respective fields may be transmitted for illustrated time periods (i.e., 4 or 8 μs).

Hereinafter, a resource unit (RU) used for a PPDU is described. An RU may include a plurality of subcarriers (or tones). An RU may be used to transmit a signal to a plurality of STAs according to OFDMA. Further, an RU may also be defined to transmit a signal to one STA. An RU may be used for an STF, an LTF, a data field, or the like.

FIG.5illustrates a layout of resource units (RUs) used in a band of 20 MHz.

As illustrated inFIG.5, resource units (RUs) corresponding to different numbers of tones (i.e., subcarriers) may be used to form some fields of an HE-PPDU. For example, resources may be allocated in illustrated RUs for an HE-STF, an HE-LTF, and a data field.

As illustrated in the uppermost part ofFIG.5, a 26-unit (i.e., a unit corresponding to 26 tones) may be disposed. Six tones may be used for a guard band in the leftmost band of the 20 MHz band, and five tones may be used for a guard band in the rightmost band of the 20 MHz band. Further, seven DC tones may be inserted in a center band, that is, a DC band, and a 26-unit corresponding to 13 tones on each of the left and right sides of the DC band may be disposed. A 26-unit, a 52-unit, and a 106-unit may be allocated to other bands. Each unit may be allocated for a receiving STA, that is, a user.

The layout of the RUs inFIG.5may be used not only for a multiple users (MUs) but also for a single user (SU), in which case one 242-unit may be used and three DC tones may be inserted as illustrated in the lowermost part ofFIG.5.

AlthoughFIG.5proposes RUs having various sizes, that is, a 26-RU, a 52-RU, a 106-RU, and a 242-RU, specific sizes of RUs may be extended or increased. Therefore, the present embodiment is not limited to the specific size of each RU (i.e., the number of corresponding tones).

FIG.6illustrates a layout of RUs used in a band of 40 MHz.

Similarly toFIG.5in which RUs having various sizes are used, a 26-RU, a 52-RU, a 106-RU, a 242-RU, a 484-RU, and the like may be used in an example ofFIG.6. Further, five DC tones may be inserted in a center frequency, 12 tones may be used for a guard band in the leftmost band of the 40 MHz band, and 11 tones may be used for a guard band in the rightmost band of the 40 MHz band.

As illustrated inFIG.6, when the layout of the RUs is used for a single user, a 484-RU may be used. The specific number of RUs may be changed similarly toFIG.5.

FIG.7illustrates a layout of RUs used in a band of 80 MHz.

Similarly toFIG.5andFIG.6in which RUs having various sizes are used, a 26-RU, a 52-RU, a 106-RU, a 242-RU, a 484-RU, a 996-RU, and the like may be used in an example ofFIG.7. Further, seven DC tones may be inserted in the center frequency, 12 tones may be used for a guard band in the leftmost band of the 80 MHz band, and 11 tones may be used for a guard band in the rightmost band of the 80 MHz band. In addition, a 26-RU corresponding to 13 tones on each of the left and right sides of the DC band may be used.

As illustrated inFIG.7, when the layout of the RUs is used for a single user, a 996-RU may be used, in which case five DC tones may be inserted.

The RU described in the present specification may be used in uplink (UL) communication and downlink (DL) communication. For example, when UL-MU communication which is solicited by a trigger frame is performed, a transmitting STA (e.g., an AP) may allocate a first RU (e.g., 26/52/106/242-RU, etc.) to a first STA through the trigger frame, and may allocate a second RU (e.g., 26/52/106/242-RU, etc.) to a second STA. Thereafter, the first STA may transmit a first trigger-based PPDU based on the first RU, and the second STA may transmit a second trigger-based PPDU based on the second RU. The first/second trigger-based PPDU is transmitted to the AP at the same (or overlapped) time period.

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

Information related to a layout of the RU may be signaled through HE-SIG-B.

FIG.8illustrates a structure of an HE-SIG-B field.

As illustrated, an HE-SIG-B field810includes a common field820and a user-specific field830. The common field820may include information commonly applied to all users (i.e., user STAs) which receive SIG-B. The user-specific field830may be called a user-specific control field. When the SIG-B is transferred to a plurality of users, the user-specific field830may be applied only any one of the plurality of users.

As illustrated inFIG.8, the common field820and the user-specific field830may be separately encoded.

The common field820may include RU allocation information of N*8 bits. For example, the RU allocation information may include information related to a location of an RU. For example, when a 20 MHz channel is used as shown inFIG.5, the RU allocation information may include information related to a specific frequency band to which a specific RU (26-RU/52-RU/106-RU) is arranged.

An example of a case in which the RU allocation information consists of 8 bits is as follows.

TABLE 18 bits indicesNumber(B7 B6 B5 B4ofB3 B2 B1 B0)#1#2#3#4#5#6#7#8#9entries0000000026262626262626262610000000126262626262626521000000102626262626522626100000011262626262652521000001002626522626262626100000101262652262626521000001102626522652262610000011126265226525210000100052262626262626261

As shown the example ofFIG.5, up to nine 26-RUs may be allocated to the 20 MHz channel. When the RU allocation information of the common field820is set to “00000000” as shown in Table 1, the nine 26-RUs may be allocated to a corresponding channel (i.e., 20 MHz). In addition, when the RU allocation information of the common field820is set to “00000001” as shown in Table 1, seven 26-RUs and one 52-RU are arranged in a corresponding channel. That is, in the example ofFIG.5, the 52-RU may be allocated to the rightmost side, and the seven 26-RUs may be allocated to the left thereof.

The example of Table 1 shows only some of RU locations capable of displaying the RU allocation information.

For example, the RU allocation information may include an example of Table 2 below.

TABLE 28 bits indicesNumber(B7 B6 B5 B4ofB3 B2 B1 B0)#1#2#3#4#5#6#7#8#9entries01000y2y1y01062626262626801001y2y1y0106262626528

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

In general, a plurality of STAs (e.g., user STAs) different from each other may be allocated to a plurality of RUs. However, the plurality of STAs (e.g., user STAs) may be allocated to one or more RUs having at least a specific size (e.g., 106 subcarriers), based on the MU-MIMO scheme.

As shown inFIG.8, the user-specific field830may include a plurality of user fields. As described above, the number of STAs (e.g., user STAs) allocated to a specific channel may be determined based on the RU allocation information of the common field820. For example, when the RU allocation information of the common field820is “00000000”, one user STA may be allocated to each of nine 26-RUs (e.g., nine user STAs may be allocated). That is, up to 9 user STAs may be allocated to a specific channel through an OFDMA scheme. In other words, up to 9 user STAs may be allocated to a specific channel through a non-MU-MIMO scheme.

For example, when RU allocation is set to “01000y2y1y0”, a plurality of STAs may be allocated to the 106-RU arranged at the leftmost side through the MU-MIMO scheme, and five user STAs may be allocated to five 26-RUs arranged to the right side thereof through the non-MU MIMO scheme. This case is specified through an example ofFIG.9.

FIG.9illustrates an example in which a plurality of user STAs are allocated to the same RU through a MU-MIMO scheme.

For example, when RU allocation is set to “01000010” as shown inFIG.9, a 106-RU may be allocated to the leftmost side of a specific channel, and five 26-RUs may be allocated to the right side thereof. In addition, three user STAs may be allocated to the 106-RU through the MU-MIMO scheme. As a result, since eight user STAs are allocated, the user-specific field830of HE-SIG-B may include eight user fields.

The eight user fields may be expressed in the order shown inFIG.9. In addition, as shown inFIG.8, two user fields may be implemented with one user block field.

The user fields shown inFIG.8andFIG.9may be configured based on two formats. That is, a user field related to a MU-MIMO scheme may be configured in a first format, and a user field related to a non-MIMO scheme may be configured in a second format. Referring to the example ofFIG.9, a user field1to a user field3may be based on the first format, and a user field4to a user field8may be based on the second format. The first format or the second format may include bit information of the same length (e.g., 21 bits).

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

For example, a first bit (i.e., B0-B10) in the user field (i.e., 21 bits) may include identification information (e.g., STA-ID, partial AID, etc.) of a user STA to which a corresponding user field is allocated. In addition, a second bit (i.e., B11-B14) in the user field (i.e., 21 bits) may include information related to a spatial configuration. Specifically, an example of the second bit (i.e., B11-B14) may be as shown in Table 3 and Table 4 below.

TABLE 3NumberNSTSNSTSNSTSNSTSNSTSNSTSNSTSNSTSTotalofNuserB3 . . . B0[1][2][3][4][5][6][7][8]NSTSentries20000-00111-412-5100100-01102-424-60111-10003-436-7100144830000-00111-4113-6130100-01102-4215-70111-10003-4317-81001-10112-4226-81100332840000-00111-41114-7110100-01102-42116-80111331181000-10012-32217-8101022228

TABLE 4NumberNSTSNSTSNSTSNSTSNSTSNSTSNSTSNSTSTotalofNuserB3 . . . B0[1][2][3][4][5][6][7][8]NSTSentries50000-00111-411115-870100-01012-321117-8011022211860000-00101-3111116-840011221111870000-00011-21111117-82800001111111181

As shown in Table 3 and/or Table 4, the second bit (e.g., B11-B14) may include information related to the number of spatial streams allocated to the plurality of user STAs which are allocated based on the MU-MIMO scheme. For example, when three user STAs are allocated to the 106-RU based on the MU-MIMO scheme as shown inFIG.9, N user is set to “3”. Therefore, values of N_STS[1], N_STS[2], and N_STS[3] may be determined as shown in Table 3. For example, when a value of the second bit (B11-B14) is “0011”, it may be set to N_STS[1]=4, N_STS[2]=1, N_STS[3]=1. That is, in the example ofFIG.9, four spatial streams may be allocated to the user field1, one spatial stream may be allocated to the user field1, and one spatial stream may be allocated to the user field3.

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

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

An MCS, MCS information, an MCS index, an MCS field, or the like used in the present specification may be indicated by an index value. For example, the MCS information may be indicated by an index 0 to an index 11. The MCS information may include information related to a constellation modulation type (e.g., BPSK, QPSK, 16-QAM, 64-QAM, 256-QAM, 1024-QAM, etc.) and information related to a coding rate (e.g., ½, ⅔, ¾, ⅚e, etc.). Information related to a channel coding type (e.g., LCC or LDPC) may be excluded in the MCS information.

In addition, a fourth bit (i.e., B19) in the user field (i.e., 21 bits) may be a reserved field.

In addition, a fifth bit (i.e., B20) in the user field (i.e., 21 bits) may include information related to a coding type (e.g., BCC or LDPC). That is, the fifth bit (i.e., B20) may include information related to a type (e.g., BCC or LDPC) of channel coding applied to the data field in the PPDU including the corresponding SIG-B.

The aforementioned example relates to the user field of the first format (the format of the MU-MIMO scheme). An example of the user field of the second format (the format of the non-MU-MIMO scheme) is as follows.

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

FIG.10illustrates an operation based on UL-MU. As illustrated, a transmitting STA (e.g., an AP) may perform channel access through contending (e.g., a backoff operation), and may transmit a trigger frame1030. That is, the transmitting STA may transmit a PPDU including the trigger frame1030. Upon receiving the PPDU including the trigger frame, a trigger-based (TB) PPDU is transmitted after a delay corresponding to SIFS.

TB PPDUs1041and1042may be transmitted at the same time period, and may be transmitted from a plurality of STAs (e.g., user STAs) having AIDs indicated in the trigger frame1030. An ACK frame1050for the TB PPDU may be implemented in various forms.

A specific feature of the trigger frame is described with reference toFIG.11toFIG.13. Even if UL-MU communication is used, an orthogonal frequency division multiple access (OFDMA) scheme or a MU MIMO scheme may be used, and the OFDMA and MU-MIMO schemes may be simultaneously used.

FIG.11illustrates an example of a trigger frame. The trigger frame ofFIG.11allocates a resource for uplink multiple-user (MU) transmission, and may be transmitted, for example, from an AP. The trigger frame may be configured of a MAC frame, and may be included in a PPDU.

Each field shown inFIG.11may be partially omitted, and another field may be added. In addition, a length of each field may be changed to be different from that shown in the figure.

A frame control field1110ofFIG.11may include information related to a MAC protocol version and extra additional control information. A duration field1120may include time information for NAV configuration or information related to an identifier (e.g., AID) of a STA.

In addition, an RA field1130may include address information of a receiving STA of a corresponding trigger frame, and may be optionally omitted. A TA field1140may include address information of a STA (e.g., an AP) which transmits the corresponding trigger frame. A common information field1150includes common control information applied to the receiving STA which receives the corresponding trigger frame. For example, a field indicating a length of an L-SIG field of an uplink PPDU transmitted in response to the corresponding trigger frame or information for controlling content of a SIG-A field (i.e., HE-SIG-A field) of the uplink PPDU transmitted in response to the corresponding trigger frame may be included. In addition, as common control information, information related to a length of a CP of the uplink PPDU transmitted in response to the corresponding trigger frame or information related to a length of an LTF field may be included.

In addition, per user information fields1160#1to1160#N corresponding to the number of receiving STAs which receive the trigger frame ofFIG.11are preferably included. The per user information field may also be called an “allocation field”.

In addition, the trigger frame ofFIG.11may include a padding field1170and a frame check sequence field1180.

Each of the per user information fields1160#1to1160#N shown inFIG.11may include a plurality of subfields.

FIG.12illustrates an example of a common information field of a trigger frame. A subfield ofFIG.12may be partially omitted, and an extra subfield may be added. In addition, a length of each subfield illustrated may be changed.

A length field1210illustrated has the same value as a length field of an L-SIG field of an uplink PPDU transmitted in response to a corresponding trigger frame, and a length field of the L-SIG field of the uplink PPDU indicates a length of the uplink PPDU. As a result, the length field1210of the trigger frame may be used to indicate the length of the corresponding uplink PPDU.

In addition, a cascade identifier field1220indicates whether a cascade operation is performed. The cascade operation implies that downlink MU transmission and uplink MU transmission are performed together in the same TXOP. That is, it implies that downlink MU transmission is performed and thereafter uplink MU transmission is performed after a pre-set time (e.g., SIFS). During the cascade operation, only one transmitting device (e.g., AP) may perform downlink communication, and a plurality of transmitting devices (e.g., non-APs) may perform uplink communication.

A CS request field1230indicates whether a wireless medium state or a NAV or the like is necessarily considered in a situation where a receiving device which has received a corresponding trigger frame transmits a corresponding uplink PPDU.

An HE-SIG-A information field1240may include information for controlling content of a SIG-A field (i.e., HE-SIG-A field) of the uplink PPDU in response to the corresponding trigger frame.

A CP and LTF type field1250may include information related to a CP length and LTF length of the uplink PPDU transmitted in response to the corresponding trigger frame. A trigger type field1260may indicate a purpose of using the corresponding trigger frame, for example, typical triggering, triggering for beamforming, a request for block ACK/NACK, or the like.

It may be assumed that the trigger type field1260of the trigger frame in the present specification indicates a trigger frame of a basic type for typical triggering. For example, the trigger frame of the basic type may be referred to as a basic trigger frame.

FIG.13illustrates an example of a subfield included in a per user information field. A user information field1300ofFIG.13may be understood as any one of the per user information fields1160#1to1160#N mentioned above with reference toFIG.11. A subfield included in the user information field1300ofFIG.13may be partially omitted, and an extra subfield may be added. In addition, a length of each subfield illustrated may be changed.

A user identifier field1310ofFIG.13indicates an identifier of a STA (i.e., receiving STA) corresponding to per user information. An example of the identifier may be the entirety or part of an association identifier (AID) value of the receiving STA.

In addition, an RU allocation field1320may be included. That is, when the receiving STA identified through the user identifier field1310transmits a TB PPDU in response to the trigger frame, the TB PPDU is transmitted through an RU indicated by the RU allocation field1320. In this case, the RU indicated by the RU allocation field1320may be an RU shown inFIG.5,FIG.6, andFIG.7.

The subfield ofFIG.13may include a coding type field1330. The coding type field1330may indicate a coding type of the TB PPDU. For example, when BCC coding is applied to the TB PPDU, the coding type field1330may be set to ‘1’, and when LDPC coding is applied, the coding type field1330may be set to ‘0’.

In addition, the subfield ofFIG.13may include an MCS field1340. The MCS field1340may indicate an MCS scheme applied to the TB PPDU. For example, when BCC coding is applied to the TB PPDU, the coding type field1330may be set to ‘1’, and when LDPC coding is applied, the coding type field1330may be set to ‘0’.

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

FIG.14describes a technical feature of the UORA scheme.

A transmitting STA (e.g., an AP) may allocate six RU resources through a trigger frame as shown inFIG.14. Specifically, the AP may allocate a 1st RU resource (AID0, RU1), a 2nd RU resource (AID0, RU2), a 3rd RU resource (AID0, RU3), a 4th RU resource (AID2045, RU4), a 5th RU resource (AID2045, RU5), and a 6th RU resource (AID3, RU6). Information related to the AID0, AID3, or AID2045may be included, for example, in the user identifier field1310ofFIG.13. Information related to the RU1to RU6may be included, for example, in the RU allocation field1320ofFIG.13. AID=0 may imply a UORA resource for an associated STA, and AID=2045 may imply a UORA resource for an un-associated STA. Accordingly, the 1st to 3rd RU resources ofFIG.14may be used as a UORA resource for the associated STA, the 4th and 5th RU resources ofFIG.14may be used as a UORA resource for the un-associated STA, and the 6th RU resource ofFIG.14may be used as a typical resource for UL MU.

In the example ofFIG.14, an OFDMA random access backoff (OBO) of a STA1is decreased to 0, and the STA1randomly selects the 2nd RU resource (AID0, RU2). In addition, since an OBO counter of a STA2/3is greater than 0, an uplink resource is not allocated to the STA2/3. In addition, regarding a STA4inFIG.14, since an AID (e.g., AID=3) of the STA4is included in a trigger frame, a resource of the RU6is allocated without backoff.

Specifically, since the STA1ofFIG.14is an associated STA, the total number of eligible RA RUs for the STA1is 3 (RU1, RU2, and RU3), and thus the STA1decreases an OBO counter by 3 so that the OBO counter becomes 0. In addition, since the STA2ofFIG.14is an associated STA, the total number of eligible RA RUs for the STA2is 3 (RU1, RU2, and RU3), and thus the STA2decreases the OBO counter by 3 but the OBO counter is greater than 0. In addition, since the STA3ofFIG.14is an un-associated STA, the total number of eligible RA RUs for the STA3is 2 (RU4, RU5), and thus the STA3decreases the OBO counter by 2 but the OBO counter is greater than 0.

FIG.15illustrates an example of a channel used/supported/defined within a 2.4 GHz band.

The 2.4 GHz band may be called in other terms such as a first band. In addition, the 2.4 GHz band may imply a frequency domain in which channels of which a center frequency is close to 2.4 GHz (e.g., channels of which a center frequency is located within 2.4 to 2.5 GHz) are used/supported/defined.

A plurality of 20 MHz channels may be included in the 2.4 GHz band. 20 MHz within the 2.4 GHz may have a plurality of channel indices (e.g., an index 1 to an index 14). For example, a center frequency of a 20 MHz channel to which a channel index 1 is allocated may be 2.412 GHz, a center frequency of a 20 MHz channel to which a channel index 2 is allocated may be 2.417 GHz, and a center frequency of a 20 MHz channel to which a channel index N is allocated may be (2.407+0.005*N) GHz. The channel index may be called in various terms such as a channel number or the like. Specific numerical values of the channel index and center frequency may be changed.

FIG.15exemplifies4channels within a 2.4 GHz band. Each of 1st to 4th frequency domains1510to1540shown herein may include one channel. For example, the 1st frequency domain1510may include a channel1(a 20 MHz channel having an index 1). In this case, a center frequency of the channel1may be set to 2412 MHz. The 2nd frequency domain1520may include a channel6. In this case, a center frequency of the channel6may be set to 2437 MHz. The 3rd frequency domain1530may include a channel11. In this case, a center frequency of the channel11may be set to 2462 MHz. The 4th frequency domain1540may include a channel14. In this case, a center frequency of the channel14may be set to 2484 MHz.

FIG.16illustrates an example of a channel used/supported/defined within a 5 GHz band.

The 5 GHz band may be called in other terms such as a second band or the like. The 5 GHz band may imply a frequency domain in which channels of which a center frequency is greater than or equal to 5 GHz 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. A specific numerical value shown inFIG.16may be changed.

A plurality of channels within the 5 GHz band include an unlicensed national information infrastructure (UNII)-1, a UNII-2, a UNII-3, and an ISM. The INII-1 may be called UNII Low. The UNII-2 may include a frequency domain called UNII Mid and UNII-2 Extended. The UNII-3 may be called UNII-Upper.

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

FIG.17illustrates an example of a channel used/supported/defined within a 6 GHz band.

The 6 GHz band may be called in other terms such as a third band or the like. The 6 GHz band may imply a frequency domain in which channels of which a center frequency is greater than or equal to 5.9 GHz are used/supported/defined. A specific numerical value shown inFIG.17may be changed.

For example, the 20 MHz channel ofFIG.17may be defined starting from 5.940 GHz. Specifically, among 20 MHz channels ofFIG.17, the leftmost channel may have an index 1 (or a channel index, a channel number, etc.), and 5.945 GHz may be assigned as a center frequency. That is, a center frequency of a channel of an index N may be determined as (5.940+0.005*N) GHz.

Accordingly, an index (or channel number) of the 2 MHz channel ofFIG.17may be 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, 153, 157, 161, 165, 169, 173, 177, 181, 185, 189, 193, 197, 201, 205, 209, 213, 217, 221, 225, 229, 233. In addition, according to the aforementioned (5.940+0.005*N)GHz rule, an index of the 40 MHz channel ofFIG.17may be 3, 11, 19, 27, 35, 43, 51, 59, 67, 75, 83, 91, 99, 107, 115, 123, 131, 139, 147, 155, 163, 171, 179, 187, 195, 203, 211, 219, 227.

Although 20, 40, 80, and 160 MHz channels are illustrated in the example ofFIG.17, a 240 MHz channel or a 320 MHz channel may be additionally added.

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

FIG.18illustrates an example of a PPDU used in the present specification.

The PPDU ofFIG.18may be called in various terms such as an EHT PPDU, a TX PPDU, an RX PPDU, a first type or N-th type PPDU, or the like. For example, in the present specification, the PPDU or the EHT PPDU may be called in various terms such as a TX PPDU, a RX PPDU, a first type or N-th type PPDU, or the like. In addition, the EHT PPDU may be used in an EHT system and/or a new WLAN system enhanced from the EHT system.

The PPDU ofFIG.18may indicate the entirety or part of a PPDU type used in the EHT system. For example, the example ofFIG.18may be used for both of a single-user (SU) mode and a multi-user (MU) mode. In other words, the PPDU ofFIG.18may be a PPDU for one receiving STA or a plurality of receiving STAs. When the PPDU ofFIG.18is used for a trigger-based (TB) mode, the EHT-SIG ofFIG.18may be omitted. In other words, an STA which has received a trigger frame for uplink-MU (UL-MU) may transmit the PPDU in which the EHT-SIG is omitted in the example ofFIG.18.

InFIG.18, an L-STF to an EHT-LTF may be called a preamble or a physical preamble, and may be generated/transmitted/received/obtained/decoded in a physical layer.

A subcarrier spacing of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and EHT-SIG fields ofFIG.18may be determined as 312.5 kHz, and a subcarrier spacing of the EHT-STF, EHT-LTF, and Data fields may be determined as 78.125 kHz. That is, a tone index (or subcarrier index) of the L-STF, L-LTF, L-SIG, RL-SIG, U-SIG, and EHT-SIG fields may be expressed in unit of 312.5 kHz, and a tone index (or subcarrier index) of the EHT-STF, EHT-LTF, and Data fields may be expressed in unit of 78.125 kHz.

In the PPDU ofFIG.18, the L-LTE and the L-STF may be the same as those in the conventional fields.

The L-SIG field ofFIG.18may include, for example, bit information of 24 bits. For example, the 24-bit information may include a rate field of 4 bits, a reserved bit of 1 bit, a length field of 12 bits, a parity bit of 1 bit, and a tail bit of 6 bits. For example, the length field of 12 bits may include information related to a length or time duration of a PPDU. For example, the length field of 12 bits may be determined based on a type of the PPDU. For example, when the PPDU is a non-HT, HT, VHT PPDU or an EHT PPDU, a value of the length field may be determined as a multiple of 3. For example, when the PPDU is an HE PPDU, the value of the length field may be determined as “a multiple of 3”+1 or “a multiple of 3”+2. In other words, for the non-HT, HT, VHT PPDI or the EHT PPDU, the value of the length field may be determined as a multiple of 3, and for the HE PPDU, the value of the length field may be determined as “a multiple of 3”+1 or “a multiple of 3”+2.

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

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

A universal SIG (U-SIG) may be inserted after the RL-SIG ofFIG.18. The U-SIB may be called in various terms such as a first SIG field, a first SIG, a first type SIG, a control signal, a control signal field, a first (type) control signal, or the like.

The U-SIG may include information of N bits, and may include information for identifying a type of the EHT PPDU. For example, the U-SIG may be configured based on two symbols (e.g., two contiguous OFDM symbols). Each symbol (e.g., OFDM symbol) for the U-SIG may have a duration of 4 us. Each symbol of the U-SIG may be used to transmit the 26-bit information. For example, each symbol of the U-SIG may be transmitted/received based on 52 data tomes and 4 pilot tones.

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

For example, the A-bit information (e.g., 52 un-coded bits) generated by the U-SIG may include a CRC field (e.g., a field having a length of 4 bits) and a tail field (e.g., a field having a length of 6 bits). The CRC field and the tail field may be transmitted through the second symbol of the U-SIG. The CRC field may be generated based on 26 bits allocated to the first symbol of the U-SIG and the remaining 16 bits except for the CRC/tail fields in the second symbol, and may be generated based on the conventional CRC calculation algorithm. In addition, the tail field may be used to terminate trellis of a convolutional decoder, and may be set to, for example, “000000”.

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

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

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

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

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

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

Preamble puncturing may be applied to the PPDU ofFIG.18. The preamble puncturing implies that puncturing is applied to part (e.g., a secondary 20 MHz band) of the full band. For example, when an 80 MHz PPDU is transmitted, an STA may apply puncturing to the secondary 20 MHz band out of the 80 MHz band, and may transmit a PPDU only through a primary 20 MHz band and a secondary 40 MHz band.

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

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

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

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

The U-SIG may be configured in unit of 20 MHz. For example, when an 80 MHz PPDU is configured, the U-SIG may be duplicated. That is, four identical U-SIGs may be included in the 80 MHz PPDU. PPDUs exceeding an 80 MHz bandwidth may include different U-SIGs.

The EHT-SIG ofFIG.18may include control information for the receiving STA. The EHT-SIG may be transmitted through at least one symbol, and one symbol may have a length of 4 us. Information related to the number of symbols used for the EHT-SIG may be included in the U-SIG.

The EHT-SIG may include a technical feature of the HE-SIG-B described with reference toFIG.8andFIG.9. For example, the EHT-SIG may include a common field and a user-specific field as in the example ofFIG.8. The common field of the EHT-SIG may be omitted, and the number of user-specific fields may be determined based on the number of users.

As in the example ofFIG.8, the common field of the EHT-SIG and the user-specific field of the EHT-SIG may be individually coded. One user block field included in the user-specific field may include information for two users, but a last user block field included in the user-specific field may include information for one user. That is, one user block field of the EHT-SIG may include up to two user fields. As in the example ofFIG.9, each user field may be related to MU-MIMO allocation, or may be related to non-MU-MIMO allocation.

As in the example ofFIG.8, the common field of the EHT-SIG may include a CRC bit and a tail bit. A length of the CRC bit may be determined as 4 bits. A length of the tail bit may be determined as 6 bits, and may be set to ‘000000’.

As in the example ofFIG.8, the common field of the EHT-SIG may include RU allocation information. The RU allocation information may imply information related to a location of an RU to which a plurality of users (i.e., a plurality of receiving STAs) are allocated. The RU allocation information may be configured in unit of 8 bits (or N bits), as in Table 1.

The example of Table 5 to Table 7 is an example of 8-bit (or N-bit) information for various RU allocations. An index shown in each table may be modified, and some entries in Table 5 to Table 7 may be omitted, and entries (not shown) may be added.

The example of Table 5 to Table 7 relates to information related to a location of an RU allocated to a 20 MHz band. For example, ‘an index 0’ of Table 5 may be used in a situation where nine 26-RUs are individually allocated (e.g., in a situation where nine 26-RUs shown inFIG.5are individually allocated).

Meanwhile, a plurality or RUs may be allocated to one STA in the EHT system. For example, regarding ‘an index 60’ of Table 6, one 26-RU may be allocated for one user (i.e., receiving STA) to the leftmost side of the 20 MHz band, one 26-RU and one 52-RU may be allocated to the right side thereof, and five 26-RUs may be individually allocated to the right side thereof.

TABLE 5NumberofIndices#1#2#3#4#5#6#7#8#9entries026262626262626262611262626262626265212262626262652262613262626262652521426265226262626261526265226262652162626522652262617262652265252185226262626262626195226262626265211052262626522626111522626265252112525226262626261135252262626521145252265226261155252265252116262626262610611726265226106118522626261061195252261061

TABLE 6NumberofIndices#1#2#3#4#5#6#7#8#9entries20106262626262612110626262652122106265226261231062652521245252—5252125242-tone RU empty (with zero users)12610626106127-34242835-42484843-50996851-582*996859262626262652 + 26261602626 + 5226262626261612626 + 52262626521622626 + 52265226261632626522652 + 26261642626 + 522652 + 26261652626 + 522652521

TABLE 7665226262652 + 262616752522652 + 26261685252 + 2652521692626262626 + 1061702626 + 522610617126265226 + 1061722626 + 5226 + 10617352262626 + 106174525226 + 106175106 + 2626262626176106 + 26262652177106 + 265226261781062652 + 2626179106 + 2652 + 2626180106 + 265252181106 + 2610618210626 + 1061

A mode in which the common field of the EHT-SIG is omitted may be supported. The mode in the common field of the EHT-SIG is omitted may be called a compressed mode. When the compressed mode is used, a plurality of users (i.e., a plurality of receiving STAs) may decode the PPDU (e.g., the data field of the PPDU), based on non-OFDMA. That is, the plurality of users of the EHT PPDU may decode the PPDU (e.g., the data field of the PPDU) received through the same frequency band. Meanwhile, when a non-compressed mode is used, the plurality of users of the EHT PPDU may decode the PPDU (e.g., the data field of the PPDU), based on OFDMA. That is, the plurality of users of the EHT PPDU may receive the PPDU (e.g., the data field of the PPDU) through different frequency bands.

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

An HE-STF ofFIG.18may be used for improving automatic gain control estimation in a multiple input multiple output (MIMO) environment or an OFDMA environment. An HE-LTF ofFIG.18may be used for estimating a channel in the MIMO environment or the OFDMA environment.

The EHT-STF ofFIG.18may be set in various types. For example, a first type of STF (e.g., lx STF) may be generated based on a first type STF sequence in which a non-zero coefficient is arranged with an interval of 16 subcarriers. An STF signal generated based on the first type STF sequence may have a period of 0.8 μs, and a periodicity signal of 0.8 μs may be repeated 5 times to become a first type STF having a length of 4 μs. For example, a second type of STF (e.g., 2×STF) may be generated based on a second type STF sequence in which a non-zero coefficient is arranged with an interval of 8 subcarriers. An STF signal generated based on the second type STF sequence may have a period of 1.6 μs, and a periodicity signal of 1.6 μs may be repeated 5 times to become a second type STF having a length of 8 μs. Hereinafter, an example of a sequence for configuring an EHT-STF (i.e., an EHT-STF sequence) is proposed. The following sequence may be modified in various ways.

The EHT-STF may be configured based on the following sequence M.
M={−1,−1,−1,1,1,1,−1,1,1,1,−1,1,1,−1,1}  <Equation 1>

The EHT-STF for the 20 MHz PPDU may be configured based on the following equation. The following example may be a first type (i.e., lx STF) sequence. For example, the first type sequence may be included in not a trigger-based (TB) PPDU but an EHT-PPDU. In the following equation, (a:b:c) may imply a duration defined as b tone intervals (i.e., a subcarrier interval) from a tone index (i.e., subcarrier index) ‘a’ to a tone index ‘c’. For example, the equation 2 below may represent a sequence defined as 16 tone intervals from a tone index −112 to a tone index 112. Since a subcarrier spacing of 78.125 kHz is applied to the EHT-STR, the 16 tone intervals may imply that an EHT-STF coefficient (or element) is arranged with an interval of 78.125*16=1250 kHz. In addition, * implies multiplication, and sqrt( )implies a square root. In addition, j implies an imaginary number.
EHT-STF(−112:16:112)={M}*(1+j)/sqrt(2)
EHT-STF(0)=0  <Equation 2>

The EHT-STF for the 40 MHz PPDU may be configured based on the following equation. The following example may be the first type (i.e., lx STF) sequence.
EHT-STF(−240:16:240)={M,0,−M}*(1+j)/sqrt(2)  <Equation 3>

The EHT-STF for the 80 MHz PPDU may be configured based on the following equation. The following example may be the first type (i.e., lx STF) sequence.
EHT-STF(−496:16:496)={M,1,−M,0,−M,1,−M}*(1+j)/sqrt(2)  <Equation 4>

The EHT-STF for the 160 MHz PPDU may be configured based on the following equation. The following example may be the first type (i.e., lx STF) sequence.
EHT-STF(−1008:16:1008)={M,1,−M,0,−M,1,−M,0,−M,−1,M,0,−M,1,−M}*(1+j)/sqrt(2)  <Equation 5>

In the EHT-STF for the 80+80 MHz PPDU, a sequence for lower 80 MHz may be identical to Equation 4. In the EHT-STF for the 80+80 MHz PPDU, a sequence for upper 80 MHz may be configured based on the following equation.
EHT-STF(−496:16:496)={−M,−1,M,0,−M,1,−M}*(1+j)/sqrt(2)  <Equation 6>

Equation 7 to Equation 11 below relate to an example of a second type (i.e.,2xSTF) sequence.
EHT-STF(−120:8:120)={M,0,−M}*(1+j)/sqrt(2)  <Equation 7>

The EHT-STF for the 40 MHz PPDU may be configured based on the following equation.
EHT-STF(−248:8:248)={M,−1,−M,0,M,−1,M}*(1+j)/sqrt(2)
EHT-STF(−248)=0
EHT-STF(248)=0  <Equation 8>

The EHT-STF for the 80 MHz PPDU may be configured based on the following equation.
EHT-STF(−504:8:504)={M,−1,M,−1,−M,−1,M,0,−M,1,M,1,−M,1,−M}*(1+j)/sqrt(2)  <Equation 9>

The EHT-STF for the 160 MHz PPDU may be configured based on the following equation.
EHT-STF(−1016:16:1016)={M,−1,M,−1,−M,−1,M,0,−M,1,M,1,−M,1,−M,0,−M,1,−M,1,M,1,−M,0,−M,1,M,1,−M,1,−M}*(1+j)/sqrt(2)
EHT-STF(−8)=0,EHT-STF(8)=0,
EHT-STF(−1016)=0,EHT-STF(1016)=0  <Equation 10>

In the EHT-STF for the 80+80 MHz PPDU, a sequence for lower 80 MHz may be identical to Equation 9. In the EHT-STF for the 80+80 MHz PPDU, a sequence for upper 80 MHz may be configured based on the following equation.
EHT-STF(−504:8:504)={−M,1,−M,1,M,1,−M,0,−M,1,M,1,−M,1,−M}*(1+j)/sqrt(2)
EHT-STF(−504)=0,
EHT-STF(504)=0  <Equation 11>

The EHT-LTF may have first, second, and third types (i.e., lx,2x,4xLTF). For example, the first/second/third type LTF may be generated based on an LTF sequence in which a non-zero coefficient is arranged with an interval of 4/2/1 subcarriers. The first/second/third type LTF may have a time length of 3.2/6.4/12.8 μs. In addition, a GI (e.g., 0.8/1/6/3.2 ps) having various lengths may be applied to the first/second/third type LTF.

Information related to a type of STF and/or LTF (information related to a GI applied to LTF is also included) may be included in a SIG-A field and/or SIG-B field or the like ofFIG.18.

A PPDU (e.g., EHT-PPDU) ofFIG.18may be configured based on the example ofFIG.5andFIG.6.

For example, an EHT PPDU transmitted on a 20 MHz band, i.e., a 20 MHz EHT PPDU, may be configured based on the RU ofFIG.5. That is, a location of an RU of EHT-STF, EHT-LTF, and data fields included in the EHT PPDU may be determined as shown inFIG.5.

An EHT PPDU transmitted on a 40 MHz band, i.e., a 40 MHz EHT PPDU, may be configured based on the RU ofFIG.6. That is, a location of an RU of EHT-STF, EHT-LTF, and data fields included in the EHT PPDU may be determined as shown inFIG.6.

Since the RU location ofFIG.6corresponds to 40 MHz, a tone-plan for 80 MHz may be determined when the pattern ofFIG.6is repeated twice. That is, an 80 MHz EHT PPDU may be transmitted based on a new tone-plan in which not the RU ofFIG.7but the RU ofFIG.6is repeated twice.

When the pattern ofFIG.6is repeated twice, 23 tones (i.e., 11 guard tones+12 guard tones) may be configured in a DC region. That is, a tone-plan for an 80 MHz EHT PPDU allocated based on OFDMA may have 23 DC tones. Unlike this, an 80 MHz EHT PPDU allocated based on non-OFDMA (i.e., a non-OFDMA full bandwidth 80 MHz PPDU) may be configured based on a 996-RU, and may include 5 DC tones, 12 left guard tones, and 11 right guard tones.

A tone-plan for 160/240/320 MHz may be configured in such a manner that the pattern ofFIG.6is repeated several times.

The PPDU ofFIG.18may be determined (or identified) as an EHT PPDU based on the following method.

A receiving STA may determine a type of an RX PPDU as the EHT PPDU, based on the following aspect. For example, the RX PPDU may be determined as the EHT PPDU: 1) when a first symbol after an L-LTF signal of the RX PPDU is a BPSK symbol; 2) when RL-SIG in which the L-SIG of the RX PPDU is repeated is detected; and 3) when a result of applying “modulo 3” to a value of a length field of the L-SIG of the RX PPDU is detected as “0”. When the RX PPDU is determined as the EHT PPDU, the receiving STA may detect a type of the EHT PPDU (e.g., an SU/MU/Trigger-based/Extended Range type), based on bit information included in a symbol after the RL-SIG ofFIG.18. In other words, the receiving STA may determine the RX PPDU as the EHT PPDU, based on: 1) a first symbol after an L-LTF signal, which is a BPSK symbol; 2) RL-SIG contiguous to the L-SIG field and identical to L-SIG; 3) L-SIG including a length field in which a result of applying “modulo 3” is set to “0”; and 4) a 3-bit PHY version identifier of the aforementioned U-SIG (e.g., a PHY version identifier having a first value).

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

For example, the receiving STA may determine the type of the RX PPDU as a non-HT, HT, and VHT PPDU, based on the following aspect. For example, the RX PPDU may be determined as the non-HT, HT, and VHT PPDU: 1) when a first symbol after an L-LTF signal is a BP SK symbol; and 2) when RL-SIG in which L-SIG is repeated is not detected. In addition, even if the receiving STA detects that the RL-SIG is repeated, when a result of applying “modulo 3” to the length value of the L-SIG is detected as “0”, the RX PPDU may be determined as the non-HT, HT, and VHT PPDU.

In the following example, a signal represented as a (TX/RX/UL/DL) signal, a (TX/RX/UL/DL) frame, a (TX/RX/UL/DL) packet, a (TX/RX/UL/DL) data unit, (TX/RX/UL/DL) data, or the like may be a signal transmitted/received based on the PPDU ofFIG.18. The PPDU ofFIG.18may be used to transmit/receive frames of various types. For example, the PPDU ofFIG.18may be used for a control frame. An example of the control frame may include a request to send (RTS), a clear to send (CTS), a power save-poll (PS-poll), BlockACKReq, BlockAck, a null data packet (NDP) announcement, and a trigger frame. For example, the PPDU ofFIG.18may be used for a management frame. An example of the management frame may include a beacon frame, a (re-)association request frame, a (re-)association response frame, a probe request frame, and a probe response frame. For example, the PPDU ofFIG.18may be used for a data frame. For example, the PPDU ofFIG.18may be used to simultaneously transmit at least two or more of the control frames, the management frame, and the data frame.

FIG.19illustrates an example of a modified transmission device and/or receiving device of the present specification.

Each device/STA of the sub-figure (a)/(b) ofFIG.1may be modified as shown inFIG.19. A transceiver630ofFIG.19may be identical to the transceivers113and123ofFIG.1. The transceiver630ofFIG.19may include a receiver and a transmitter.

A processor610ofFIG.19may be identical to the processors111and121ofFIG.1. Alternatively, the processor610ofFIG.19may be identical to the processing chips114and124ofFIG.1.

A memory620ofFIG.19may be identical to the memories112and122ofFIG.1. Alternatively, the memory620ofFIG.19may be a separate external memory different from the memories112and122ofFIG.1.

Referring toFIG.19, a power management module611manages power for the processor610and/or the transceiver630. A battery612supplies power to the power management module611. A display613outputs a result processed by the processor610. A keypad614receives inputs to be used by the processor610. The keypad614may be displayed on the display613. A SIM card615may be an integrated circuit which is used to securely store an international mobile subscriber identity (IMSI) and its related key, which are used to identify and authenticate subscribers on mobile telephony devices such as mobile phones and computers.

Referring toFIG.19, a speaker640may output a result related to a sound processed by the processor610. A microphone641may receive an input related to a sound to be used by the processor610.

The STA described below may be the apparatus ofFIGS.1and/or19, and the PPDU may be the PPDU ofFIG.18. The STA may be an AP or a non-AP STA. The STA (for example, AP or non-AP STA) described below may be a STA that supports multi-link (for example, an AP multi-link device (MLD) or a non-AP STA MLD).

Discovery or Scanning Operation in a Wireless LAN System

In order to access the wireless LAN network, the STA should perform network discovery. Such discovery may be performed through a network scanning process. The scanning scheme may be divided into active scanning and passive scanning.

FIG.20is a diagram illustrating an embodiment of passive scanning operation.

Referring toFIGS.20, AP-12010and AP-22020may transmit beacon frames during a pre-set time interval. The STA2030may receive information related to the AP and/or the wireless LAN system through the received beacon frame.

The beacon frame is an example of a management frame in IEEE 802.11. The beacon frame may be transmitted periodically. An STA that performs scanning based on passive scanning may receive a beacon frame while moving channels. Upon receiving the beacon frame, the STA2030may store BSS-related information included in the received beacon frame, move to the next channel, and perform the passive scanning on the next channel.

FIG.21illustrates technical features related to active scanning.

Referring toFIG.21, the STA2130performing active scanning may transmit a probe request frame and wait for a response thereto in order to discover which APs2110and2120exist in the neighbor while moving channels. A responder may transmit, to the STA that has transmitted the probe request frame, a probe response frame in response to the probe request frame. The responder may be an STA that last transmitted a beacon frame in the BSS of the channel being scanned. In the BSS, since the AP transmits a beacon frame, the AP may become the responder, and in the IBSS, since STAs in the IBSS transmit beacon frames in turn, the responder may be changed.

When the STA transmits a probe request frame through channel1and receives a probe response frame through channel1, the STA stores BSS-related information included in the received probe response frame, moves to the next channel (for example, channel2), and repeats the scanning in the same way.

Herein,FIG.22shows an example of the operation of scanning and thereafter.

The example ofFIG.22may be performed based onFIGS.20and21. That is, the user STA may receive the beacon frame ofFIG.20. Alternatively, the user-STA may transmit a probe request frame and receive a probe response frame as shown inFIG.21.

Thereafter, an authentication process as shown inFIG.9may be performed. For example, the STA may transmit an authentication request frame to the AP, and in response thereto, the AP may transmit an authentication response frame to the STA. An authentication frame used for an authentication request/response corresponds to a management frame.

The authentication frames may include information related to an authentication algorithm number, an authentication transaction sequence number, a status code, a challenge text, a robust security network (RSN), and a finite cyclic group.

The STA may transmit the authentication request frame to the AP. The AP may determine whether to allow the authentication of the STA based on the information included in the received authentication request frame. The AP may provide the authentication processing result to the STA via the authentication response frame.

When the STA is successfully authenticated, the 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 the AP transmits an association response frame to the STA in response.

The association request frame may include, for example, information related to various capabilities, a beacon listen interval, a service set identifier (SSID), a supported rate, a supported channel, RSN, a mobility domain, a supported operating class, a traffic indication map (TIM) broadcast request, and an interworking service capability. The association response frame may include, for example, information related to various capabilities, a status code, an association ID (AID), a supported rate, an enhanced distributed channel access (EDCA) parameter set, a received channel power indicator (RCPI), a received signal-to-noise indicator (RSNI), a mobility domain, a timeout interval (association comeback time), an overlapping BSS scanning parameter, a TIM broadcast response, and a QoS map.

In the IEEE802.11ax system, the AP can allocate only one resource unit (RU) to one STA, and the AP may transmit/receive data to and from the STA through the one RU allocated to the STA. This is a method that can reduce the complexity of the UE, but can reduce the efficiency of resource use.FIG.23shows an example of this.

FIG.23is a diagram illustrating an embodiment of a method of allocating only one RU to one STA.

Referring toFIG.23, in the 80 MHz bandwidth, when subchannels corresponding to resource unit (RU)1and RU4are available for STA1(e.g. CCA result is idle), and when subchannels corresponding to RU2and RU3are available for STA2, the AP may allocate resources for only one of RU1or RU4to STA1, may allocate only one of RU2and RU3to STA2. That is, even if there are multiple RU s available for the STA, the AP may allocate only one RU to one STA. In addition, since the AP cannot simultaneously allocate RU2and RU3to STA2in the existing IEEE802.11ax system, the AP may allocate only one of RU2and RU3to STA2. In this case, if DL/UL data exists only for STA1and STA2, since one of RU1or RU4and one of RU2and RU3cannot be used, resource waste may occur.

If STA1or STA2can be allocated one or more RUs, the AP may allocate RU1and RU4to STA1, and may transmit/receive data through RU1and RU4. The AP may allocate RU2and RU3to STA2, and may transmit/receive data through RU2and RU3.

FIG.24is a diagram illustrating an embodiment of a method of allocating multiple RUs.

Referring toFIG.24, STA1may be allocated RU1and RU4, and STA2may be allocated RU2and RU3. Different data may be transmitted through multiple RUs allocated to STA1and STA2. Accordingly, data transmission efficiency may be increased.

FIG.25is a diagram illustrating an embodiment of a method for transmitting PSDU through multiple RUs.

Referring toFIG.25, for example, the AP may transmit data (/PSDU) for STA1through RU1and RU4. Different data (for example, one part of PSDU for STA1is transmitted through RU1and another part of PSDU for STA1is transmitted through RU4) may be transmitted to each RU. For example, when one PSDU is transmitted through multiple RUs, different information bits may be transmitted through different RUs. For example, one PSDU may consist of part1and part2, and part1and part2may be transmitted through different RUs, respectively. For example, one PSDU may be transmitted through different RUs alternately one bit at a time at the bit level. PSDU may be transmitted through RU2and RU3allocated to STA2in the same manner.

Unlike the above method, when multiple RUs are allocated, different PSDUs may be transmitted through each RU.

FIG.26is a diagram illustrating an embodiment of a method for transmitting PSDU through multiple RUs.

Referring toFIG.26, the AP may transmit PSDU1for STA1through RU1and may transmit PSDU2for STA1through RU4. The AP may transmit PSDU1for STA2through RU2and may transmit PSDU2for STA2through RU3.

In order to increase the reliability of data transmission, there is a method for transmitting the same data via multiple RUs. Hereinafter, a method for transmitting the same data through multiple RUs will be described.

FIG.27is a diagram illustrating an embodiment of a method for transmitting a PSDU through multiple RUs.

Referring toFIG.27, RU1and RU4are allocated to STA1, and data transmitted through RU1(for example, PSDU, HARQ burst, HARQ data, information bits, etc.) may be the same as data transmitted through RU4. The STA could acquire data even by successfully receiving only one of the two data (for example, PSDU). Also, in some cases, data may be received more reliably by combining RU1and RU4. Also for STA2, the data (PSDU #2) transmitted through RU2and RU3are the same.

Hereinafter, when allocating multiple RUs to one STA, a signaling method for transmitting different data via each RU and a signaling method for transmitting the same data via different RUs will be described.

When multiple RUs are allocated to one UE, if the same data is assigned for different RUs, information indicating that the same data is included in different RUs should be transmitted, so that the receiving UE can determine whether to combine data received into the corresponding RUs. Also, when different data is received from different RU, the STA should be able to determine in what order to process the data and upload it to the MAC, and a method or rule for this is required.

Signaling Method when the Same Data is Included in Different RUs

Method 1:

The SIG (for example, HE/EHT-SIG A/B/C, HARQ-SIG, etc.) field may include information on whether a specific RU includes the same data as data transmitted from another RU. For example, when RU1and RU4are allocated to STA1, the User Info field for RU1and RU4of the SIG may include indication information on whether the same data as the previous RU is included. The receiving UE can know that the same data transmission is performed in multiple RUs allocated to it based on the SIG field, can perform combining data received through multiple RUs. If it does not indicate the transmission of the same data, the receiving UE can handle as different data transmission.

For example, Same data indication (1 bit): When a corresponding field value is configured to 1, when multiple RUs are allocated to an STA, it may mean that the same data is transmitted through multiple RUs. If the Same data indication field value is configured to 0, it indicates that when multiple RUs are allocated to an STA, different data is transmitted through each RU. The corresponding value may be configured to the opposite value. When a Single RU is allocated, the corresponding bit may not be included or may have a value of 0.

Method 1-1:

When the same data is transmitted via multiple RUs, it may be a simple method to transmit the same data via all allocated RUs. For example, when three RUs are allocated to an STA and the same data is transmitted via two or more RUs, the same data is transmitted via all three allocated RUs, and other data may not be transmitted only via a specific RU. That is, the indication may be set to 1 for all assigned RUs or configured to 0 for all RUs.FIG.28is a diagram illustrating an embodiment of method 1-1.

Referring toFIG.28, since multiple RUs of RU1and RU4are allocated to STA1, and the same data (PSDU #1) is transmitted to each RU, Same Data Indication (SDI) may be set to 1 in information corresponding to RU1and RU4. For example, data transmitted through RU4may be duplicated data transmitted through RU1. Since multiple RUs of RU2and RU3are allocated to STA2, and different data (PSDU #1for RU2, PSDU #2for RU3) are transmitted to each RU, in order to indicate this, Same Data Indication (SDI) may be set to 0 in information corresponding to RU2and RU3. Assuming that all of the RUs allocated to the STA include the same data or different data, SDI per RU may not be included, and one SDI may be included per STA. For example, user-specific information may consist of RU common information and RU-specific information, in this case, RU common information may include information common to the allocated RUs (for example, STA information), the RU-specific information may include information specific to each RU. SDI may be included in RU common information.FIG.28shows an example in which each SDI is included in RU-specific information. However, SDI may be included in RU common information rather than RU-specific information.

FIG.28is a case of MU transmission in which data is transmitted to STA1and STA2, and even in the case of SU transmission in which data is transmitted to only one STA, the same data may be transmitted to two multiple RUs allocated to an STA, and information indicating that the same data is included in multiple RUs may be transmitted.

For example, when two RUs are allocated to an STA, information related to whether the same data is included in the two allocated RUs (that is, whether data is duplicated and transmitted) may be included in the header (for example, SIG) of the PPDU, or information related to whether the same data is included in the two allocated RUs may be included for each RU, or only 1-bit information (that is, whether the same data is included in the two allocated RUs) may be included for each STA. That is, whether the first PSDU transmitted through the first RU and the second PSDU transmitted through the second RU are the same data (for example, data that duplicates data transmitted through the first RU is transmitted through the second RU) may be included in the SIG field of the PPDU including the first PSDU and second PSDU.

The transmitting STA may transmit a PPDU including a second data field that is a duplicate of the first data field. Through the duplicated data field, the receiving STA may more reliably receive data through a frequency diversity gain. In addition, information related to that the first data field and the second data field include the same data may be transmitted, so that the receiving STA could know that the first data field and the second data field are the same data. Accordingly, the receiving STA could combine the data received from each RU and receive the frame more reliably.

The above terms may be changed to other names.

Method 1-2:

RUs in which Indication is set to 1 may include the same data. For example, when RU1,2,4are assigned to one UE, the indication is set to 1 for RU1and RU4, and the indication is set for RU2is set to 0, the receiving UE may determine that the same data is transmitted via RU1and RU4, may attempt combining them, and may determine that different data is transmitted via RU2. In this case, there is only one same data that can be transmitted via other RUs, and the RUs in which the indication is set to 0 have different data. In Method 1-2, there may be only one identical data (that is, duplicated data) transmitted through multiple RUs.FIG.29is a diagram illustrating an embodiment of method 1-2.

Referring toFIG.29, since multiple RUs of RU1, RU2, and RU4are allocated to STA1, and the same data (PSDU #1) is transmitted via RU1and RU4, the Same Data Indication (SDI) included in the information for RU1and RU4may be set to 1, since different data (PSDU #2) is transmitted via RU2, the SDI included in the information for RU2may be set to 0. Since multiple RUs of RU3, RU5, RU6, RU7, and RU8are allocated to STA2, and the same data (PSDU #1) is transmitted via RU3, RU6, and RU8, the SDI included in information for RU3, RU6, RU8may be set to 1, since different data (PSDU #2for RU5and PSDU #3for RU6) are transmitted via RU5and RU7, SDI included in information for RU5and RU7may be set to 0. Since the same data is transmitted via RU3, RU6, and RU8, the same data cannot be transmitted via RU5and RU7. Otherwise, conversely, for the STA, a method of transmitting the same data via RUs5and7and transmitting different data via RUs3,6, and8may be used.

Method 1-3:

The toggle bit method may be used to indicate which RUs among the allocated RUs contain the same data and different data. When the same data as the data included in the previous RU is included in the order of the RU assigned to the STA, the Same data indication (SDI) value is the same as the value of the previous SDI, when different data is included, it has a toggled (that is, different) value. The initial value for the first RU of SDI may start with either 0 or 1.

For example, when four RUs are assigned to one UE in the order of RU1,2,3,4, and the indication toggle bit of RU1, RU2, RU3, and RU4are set to 0 0 1 0, respectively, the UE may transmit the same data via RU1and RU2, and transmit different data via RU3and RU4different from other RUs. That is, data A may be transmitted via RU1and RU2, data B may be transmitted via RU3, and data C may be transmitted via RU4.

For example, if the indication toggle bit is set to 0 0 1 1 respectively, the UE may determine that the same data is transmitted via RU1and RU2, and the same data is transmitted via RU3and RU4. That is, data A may be transmitted via RU1and RU2, and data B may be transmitted via RU3and RU4.

In method 1-3, the same data may exist only in RUs in a contiguous order.FIG.30is a diagram illustrating an embodiment of method 1-3.

Referring toFIG.30, in the above example, since multiple RUs of RU1, RU2, and RU4are allocated to STA1, the SDI of RU1is set to 0, and the same data (PSDU #1) as RU1is transmitted via RU2, the SDI of RU2is set to 0, which is the same value as RU1. Since different data (PSDU #2) is transmitted via RU4, SDI is toggled and set to 1.

Multiple RUs of RU3, RU5, RU6, RU7, and RU8may be allocated to STA2, data PSDU #2is transmitted to RU5and RU6, data PSDU #3is transmitted to RU7and RU8, different data PSDU #1is transmitted to RU3. Therefore, the SDI for RU3is initially set to 0. Since the data transmitted via RU5is different from the data transmitted via RU3, the SDI for RU5is toggled and set to 1. Since the data transmitted via RU6is the same as the data transmitted via RU5, the SDI of RU6is set to 1 equal to RU5. Since the data transmitted in RU7is different from the data transmitted in RU6, the SDI of RU7is toggled and set to 0.

Since the data transmitted in RU8is the same as transmitted in RU7, the SDI for RU8is set to 0 equal to RU7.

The toggle method can be operated efficiently only when the UE reads all user-specific information for all RUs allocated to it.

Method 1-4:

In order to complement method 1-2, sequence numbers (SNs) may be assigned to allocated RUs to distinguish which RUs include the same data. That is, sequence numbers of RUs including the same data may have the same value. The receiving UE may perform combining on data received from the RUs having the same sequence number. For example, when four RUs such as RUs1,2,3,4are allocated to one UE, for each RU, if the sequence number for RU1is SN0, the sequence number for RU2is SN1, the sequence number for RU3is SN2, and the sequence number for RU4is SN3, since the four allocated RUs have different sequence numbers, all of the allocated RUs include different data. If the sequence number (SN) related to RU1and RU4is 0, and if the SNs related to RU2and RU3are 1, the same data is transmitted to RU1and RU4, and the same data may be transmitted to RU2and RU3. Data transmitted to RU1and RU4and data transmitted to RU2and RU3may be different.FIG.31is a diagram illustrating an embodiment of method 1-4.

Referring toFIG.31, multiple RUs of RU1, RU2, and RU4may be allocated to STA1. Since the same data (PSDU #1) is transmitted to RU1and RU4, each Sequence Number (SN) included in the information corresponding to RU1and RU4may be set to 0. Since data (PSDU #2) different from that of RU1and RU4is transmitted to RU2, SN included in information corresponding to RU2may be set to 1. Multiple RUs of RU3, RU5, RU6, RU7, and RU8may be allocated to STA2. Since the same data (PSDU #1) is transmitted to RU3, RU6, and RU8, the SN included in the information corresponding to RU3, RU6, and RU8may be set to 0. Since other data (PSDU #2to RU5and PSDU #3to RU6) are transmitted to RU5and RU7, the SN included in the information corresponding to RU5may be set to 1, and the SN included in the information corresponding to RU7may be set to 2.

FIG.32is a diagram illustrating an embodiment of method 1-4.

Referring toFIG.32, multiple RUs of RU1, RU2, and RU4may be allocated to STA1. Since the SN of RU1is set to 0 and the same data (PSDU #1) as RU1is transmitted to RU2, the SN of RU2may be set to 0, which is the same value as RU1. Since different data (PSDU #2) is transmitted to RU4, SN may be set to 1, which is a new value.

Multiple RUs of RU3, RU5, RU6, RU7, and RU8may be allocated to STA2, the same data PSDU #2is transmitted to RU5and RU6, the same data PSDU #3is transmitted to RU7and RU8, and different data PSDU #1is transmitted to RU3. Accordingly, the SN of RU3is set to 0. Although the same data is transmitted to RU5and RU6, the SN of RU5and RU6is set to 1, because the data is different from that of RU3. Since the data transmitted to RU7and RU8are the same and different from the data of RU3, RU5, and RU6, the SNs of RU7and RU8are set to 2.

According to method 1-4, one or more duplicated data may be transmitted through different RUs at the same time.

Method 2:

When the same data is transmitted together with information on whether the same data is transmitted to multiple RUs, a sequence number (SN) indicating which RUs include the same data is included in the SIG information for each RU and transmitted. This method has a signaling overhead compared to the methods defined in Method 1 above, but has the advantage of providing full flexibility in scheduling.

FIG.33is a diagram illustrating an embodiment according to method 2.

Referring toFIG.33, since the same data (PSDU #1) is transmitted to RU1and RU4allocated to STA1, SDI of RU1and RU4is set to 1 and SN is set to 0. Since different data (PSDU #2) is transmitted to RU2allocated to STA1, SDI of RU2is set to 0 and SN is set to 1.

Since the same data (PSDU #1) is transmitted to RU3, RU6, and RU8allocated to STA2, SDI of RU3, RU6, and RU8is set to 1 and SN is set to 0, which is an initial value. Since different data (PSDU #2) is transmitted to RU5, SDI of RU5is set to 0, SN is set to 1, which is the next value. Since different data (PSDU #3) is transmitted to RU7, SDI of RU7is set to 0, SN is set to 2, which is the next value.

FIG.34is a diagram illustrating an embodiment according to method 2.

Referring toFIG.34, since the same data PSDU #1is transmitted to RU1and RU2allocated to STA1, SDI of RU1and RU2is set to 1 and SN is set to 0. Since different data (PSDU #2) is transmitted to RU4allocated to STA1, SDI of RU4is set to 0, and SN is set to 1.

Since the data (PSDU #1) transmitted to RU3allocated to STA2is the only data without duplicated data transmission, SDI is set to 0, and SN is set to 0, which is an initial value. Since the same data (PSDU #2) is transmitted to RU5and RU6, SDI of RU5and RU6may be set to 1, and SN may be set to the next value of 1. Since the same data (PSDU #3) is transmitted to RU7and RU8, SDI of RU7and RU8may be set to 1, and SN may be set to the next value of 2.

FIG.35is a diagram illustrating an embodiment of an operation of a transmitting STA.

The transmitting STA operation may be performed based on method 1-1.

Referring toFIG.35, a transmitting STA may receive an allocation of an RU (S3510). For example, the transmitting STA may receive an allocation of a first resource unit (RU) and a second RU from the receiving STA.

The transmitting STA may generate a PPDU (S3520). For example, the transmitting STA may generate a physical protocol data unit (PPDU) including a first data field, a second data field, and data replication information. The second data field may be generated by duplicating the first data field. The data duplication information may include information related to that the first and second data fields are identical.

For example, in the case of SU transmission in which data is transmitted to only one STA, the same data may be transmitted via two multiple RUs allocated to the STA, and information indicating that the same data is included in multiple RUs may be transmitted.

For example, when two RUs are allocated to an STA, information related to whether the same data is included in the two allocated RUs (that is, whether data is duplicated and transmitted) may be included in the header (for example, SIG) of the PPDU, or information related to whether the same data is included in the two allocated RUs may be included for each RU, or only 1-bit information (that is, whether the same data is included in the two allocated RUs) may be included for each STA. That is, whether the first PSDU transmitted through the first RU and the second PSDU transmitted through the second RU are the same data (for example, data that duplicates data transmitted through the first RU is transmitted through the second RU) may be included in the SIG field of the PPDU including the first PSDU and second PSDU.

For example, the PPDU may include a first physical service data unit (PSDU) and a second PSDU. The first data field may be generated in a media access control (MAC) layer and included in the first PSDU, and the second data field may be generated in the MAC layer and included in the second PSDU.

For example, the PPDU may include a preamble field and a training field, and the preamble field and the training field may be generated in a physical (PHY) layer.

For example, the first RU and the second RU may be located in non-adjacent frequency bands.

For example, the data duplication information may be 1-bit information indicating whether the first data field and second data field transmitted through the first RU and second RU are the same information configured with the same bitstream.

For example, the preamble may include a legacy preamble, U-signal (SIG), and EHT-signal (SIG) fields.

The transmitting STA may transmit a PPDU (S3530). For example, the transmitting STA may transmit the PPDU to the receiving STA. The first data field may be transmitted through the first RU, and the second data field may be transmitted through the second RU.

FIG.36is a diagram illustrating an embodiment of an operation of a receiving STA.

Referring toFIG.36, the receiving STA may allocate an RU (S3610). For example, the receiving STA may allocate a first resource unit (RU) and a second RU to the transmitting STA.

The receiving STA may receive the PPDU (S3620). For example, the transmitting STA may receive a physical protocol data unit (PPDU) including a first data field, a second data field, and data replication information. The first data field may be transmitted through the first RU, and the second data field may be transmitted through the second RU. The second data field may be generated by duplicating the first data field. The data duplication information may include information related to that the first data field and second data field are the same.

For example, in the case of SU transmission in which data is transmitted to only one STA, the same data may be transmitted via two multiple RUs allocated to the STA, and information indicating that the same data is included in multiple RUs may be transmitted.

For example, when two RUs are allocated to an STA, information related to whether the same data is included in the two allocated RUs (that is, whether data is duplicated and transmitted) may be included in the header (for example, SIG) of the PPDU, or information related to whether the same data is included in the two allocated RUs may be included for each RU, or only 1-bit information (that is, whether the same data is included in the two allocated RUs) may be included for each STA. That is, whether the first PSDU transmitted through the first RU and the second PSDU transmitted through the second RU are the same data (for example, data that duplicates data transmitted through the first RU is transmitted through the second RU) may be included in the SIG field of the PPDU including the first PSDU and second PSDU.

For example, the PPDU may include a first physical service data unit (PSDU) and a second PSDU. The first data field may be generated in a media access control (MAC) layer and included in the first PSDU, and the second data field may be generated in the MAC layer and included in the second PSDU.

For example, the PPDU may include a preamble field and a training field, and the preamble field and the training field may be generated in a physical (PHY) layer.

For example, the first RU and the second RU may be located in non-adjacent frequency bands.

For example, the data duplication information may be 1-bit information indicating whether the first data field and second data field transmitted through the first RU and second RU are the same information configured with the same bitstream.

For example, the preamble may include a legacy preamble, U-signal (SIG), and EHT-signal (SIG) fields.

Some of the detailed steps shown in the examples ofFIGS.35and36may not be essential steps and may be omitted. In addition to the steps shown inFIGS.35and36, other steps may be added, and the order of the steps may vary. Some of the above steps may have their own technical meaning.

The technical features of the present disclosure described above may be applied to various devices and methods. For example, the above-described technical features of the present disclosure may be performed/supported through the apparatus ofFIGS.1and/or19. For example, the above-described technical features of the present disclosure may be applied only to a part ofFIGS.1and/or19. For example, the technical features of the present disclosure described above may be implemented based on the processing chips114and124ofFIG.1, may be implemented based on the processors111and121and the memories112and122ofFIG.1, or may be implemented based on the processor610and the memory620ofFIG.19. For example, the apparatus of the present disclosure includes a memory and a processor operatively coupled to the memory. The processor may be configured to receive, from a receiving STA, an allocation of a first resource unit (RU) and a second RU. The processor may be configured to generate a physical protocol data unit (PPDU) including a first data field, a second data field, and data duplication information. The second data field may be generated by duplicating the first data field. The data duplication information may include information related to that the first data field and the second data field are the same. The processor may be configured to transmit, to the receiving STA, the PPDU. The first data field may be transmitted through the first RU and the second data field may be transmitted through the second RU.

The technical features of the present disclosure may be implemented based on a computer readable medium (CRM). For example, a CRM proposed by the present disclosure may store instructions which, based on being executed by at least one processor of a station (STA) supporting multi-link in a wireless local area network system, cause the STA to perform operations. The operations may include the step of receiving, from a receiving STA, an allocation of a first resource unit (RU) and a second RU. The operations may include the step of generating a physical protocol data unit (PPDU) including a first data field, a second data field, and data duplication information. The second data field may be generated by duplicating the first data field. The data duplication information may include information related to that the first data field and the second data field are the same. The operations may include the step of transmitting, to the receiving STA, the PPDU. The first data field may be transmitted through the first RU and the second data field may be transmitted through the second RU.

The instructions stored in the CRM of the present disclosure may be executed by at least one processor. At least one processor related to CRM in the present disclosure may be the processors111and121or the processing chips114and124ofFIG.1, or the processor610ofFIG.19. Meanwhile, the CRM of the present disclosure may be the memories112and122ofFIG.1, the memory620ofFIG.19, or a separate external memory/storage medium/disk.

The foregoing technical features of this specification are applicable to various applications or business models. For example, the foregoing technical features may be applied for wireless communication of a device supporting artificial intelligence (AI).

Artificial intelligence refers to a field of study on artificial intelligence or methodologies for creating artificial intelligence, and machine learning refers to a field of study on methodologies for defining and solving various issues in the area of artificial intelligence. Machine learning is also defined as an algorithm for improving the performance of an operation through steady experiences of the operation.

An artificial neural network (ANN) is a model used in machine learning and may refer to an overall problem-solving model that includes artificial neurons (nodes) forming a network by combining synapses. The artificial neural network may be defined by a pattern of connection between neurons of different layers, a learning process of updating a model parameter, 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 includes one or more neurons, and the artificial neural network may include synapses that connect neurons. In the artificial neural network, each neuron may output a function value of an activation function of input signals input through a synapse, weights, and deviations.

A model parameter refers to a parameter determined through learning and includes a weight of synapse connection and a deviation of a neuron. A hyperparameter refers to a parameter to be set before learning in a machine learning algorithm and includes a learning rate, the number of iterations, a mini-batch size, and an initialization function.

Learning an artificial neural network may be intended to determine a model parameter for minimizing a loss function. The loss function may be used as an index for determining an optimal model parameter in a process of learning the artificial neural network.

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

Supervised learning refers to a method of training an artificial neural network with a label given for training data, wherein the label may indicate a correct answer (or result value) that the artificial neural network needs to infer when the training data is input to the artificial neural network. Unsupervised learning may refer to a method of training an artificial neural network without a label given for training data. Reinforcement learning may refer to a training method for training an agent defined in an environment to choose an action or a sequence of actions to maximize a cumulative reward in each state.

Machine learning implemented with a deep neural network (DNN) including a plurality of hidden layers among artificial neural networks is referred to as deep learning, and deep learning is part of machine learning. Hereinafter, machine learning is construed as including deep learning.

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

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

Robots may be classified into industrial, medical, household, military robots and the like according uses or fields. A robot may include an actuator or a driver including a motor to perform various physical operations, such as moving a robot joint. In addition, a movable robot may include a wheel, a brake, a propeller, and the like in a driver to run on the ground or fly in the air through the driver.

The foregoing technical features may be applied to a device supporting extended reality.

Extended reality collectively refers to virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology is a computer graphic technology of providing a real-world object and background only in a CG image, AR technology is a computer graphic technology of providing a virtual CG image on a real object image, and MR technology is a computer graphic technology of providing virtual objects mixed and combined with the real world.

MR technology is similar to AR technology in that a real object and a virtual object are displayed together. However, a virtual object is used as a supplement to a real object in AR technology, whereas a virtual object and a real object are used as equal statuses in MR technology.

XR technology may be applied to a head-mount display (HMD), a head-up display (HUD), a mobile phone, a tablet PC, a laptop computer, a desktop computer, a TV, digital signage, and the like. A device to which XR technology is applied may be referred to as an XR device.

Claims disclosed in the present specification can be combined in various ways. For example, technical features in method claims of the present specification can be combined to be implemented or performed in an apparatus, and technical features in apparatus claims of the present specification can be combined to be implemented or performed in a method. Further, technical features in method claims and apparatus claims of the present specification can be combined to be implemented or performed in an apparatus. Further, technical features in method claims and apparatus claims of the present specification can be combined to be implemented or performed in a method.