WO2017014551A1 - Method for transmitting signal based on channel bonding and device therefor - Google Patents

Abstract

The present specification relates to a method by which a station (STA) transmits a signal through channel bonding in a wireless LAN (WLAN) system, and a device therefor. To this end, a first station (STA) transmits a wireless frame to a second STA, wherein the wireless frame is transmitted by channel-bonding two or more channels. If the wireless frame is transmitted by using channel bonding of four channels, the first STA transmits a first preamble through a first bonding frequency domain including, among the four channels, a first channel, a second channel, and an interval frequency domain corresponding to an interval between the first channel and the second channel, and can repeatedly transmit the first preamble through a second bonding frequency domain including, among the four channels, a third channel, a fourth channel, and an interval frequency domain corresponding to an interval between the third channel and the fourth channel.

Description

Channel bonding based signal transmission method and apparatus therefor

The following description relates to channel bonding in a mobile communication system, and more particularly, to a method and apparatus for transmitting a signal based on channel bonding in a station in a WLAN system.

The standard for WLAN technology is being developed as an Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard. IEEE 802.11a and b are described in 2.4. Using unlicensed band at GHz or 5 GHz, IEEE 802.11b provides a transmission rate of 11 Mbps and IEEE 802.11a provides a transmission rate of 54 Mbps. IEEE 802.11g applies orthogonal frequency-division multiplexing (OFDM) at 2.4 GHz to provide a transmission rate of 54 Mbps. IEEE 802.11n applies multiple input multiple output OFDM (MIMO-OFDM) to provide a transmission rate of 300 Mbps for four spatial streams. IEEE 802.11n supports channel bandwidths up to 40 MHz, in this case providing a transmission rate of 600 Mbps.

The WLAN standard uses a maximum of 160MHz bandwidth, supports eight spatial streams, and supports IEEE 802.11ax standard through an IEEE 802.11ac standard supporting a speed of up to 1Gbit / s.

Meanwhile, IEEE 802.11ad defines performance enhancement for ultra-high throughput in the 60 GHz band, and IEEE 802.11ay for channel bonding and MIMO technology is introduced for the first time in the IEEE 802.11ad system.

While data transmission based on channel bonding can provide high throughput, this may require a new Physical Protocol Data Unit (PPDU) format.

For the IEEE 802.11ay standardization as described above, a study on a new PPDU format considering a compatibility with an existing legacy system (eg, 11ad STA), and a method and apparatus for transmitting the same is required.

According to an aspect of the present invention for solving the above problems, in a method in which a first station (STA) transmits a signal through channel bonding in a WLAN system, the first STA is connected to a second STA. In the case of transmitting a radio frame, the radio frame is transmitted by channel bonding two or more channels, and when the radio frame is transmitted by using channel bonding of four channels, a first channel, a second channel, and Transmitting a first preamble through a first bonding frequency region including an interval frequency region corresponding to an interval between the first channel and the second channel, wherein a third channel, a fourth channel, and the We propose a signal transmission method for repeatedly transmitting the first preamble through a second bonding frequency region including an interval frequency region corresponding to an interval between a third channel and the fourth channel. .

The first preamble may include a Short Training Field (STF) and a Channel Estimation (CE) field, and the STF sequence and the CE for two-channel bonding even when the radio frame is transmitted using four channel bonding. You can use sequences.

The first STA may sequentially transmit preamble information for the first type STA, a header for the first type STA, and a header for the second type STA through the first channel and the second channel, respectively. The first preamble may be transmitted as a preamble for a second type STA through the first bonding frequency domain.

Meanwhile, the header for the first type STA includes duplicated information whether the header for the second type STA transmitted through the first channel and the header for the second type STA transmitted through the second channel include independent information. It may include information about whether to include.

In addition, one of the header for the first type STA and the header for the second type STA may include bonding indication information indicating which of the first to fourth channels is to be used for channel bonding.

The second STA may attempt to receive only a channel corresponding to a primary channel of the first to fourth channels until the bonding indication information is received.

Preferably, the first STA transmits an RTS frame to the second STA and receives a CTS frame from the second STA before transmitting the radio frame using channel bonding, wherein the RTS frame and the CTS Any one or more of the frames may include bonding indication information indicating which of the first to fourth channels will be used for channel bonding.

When the radio frame supports one or more of MU-MIMO or OFDMA, the first preamble may include an Enhanced Directional Multi-Gigabit (EDMG) header A and an EDMG header B, and the radio frame includes the MU- If the MIMO and the OFDMA are not supported, the first preamble may not include the EDMG header B.

The first STA may perform a performance negotiation process through a beacon frame or a frame exchange for association before transmitting the radio frame to the second STA. One or more of information on whether channel bonding capability, power consumption capability, and RTC and CTS frame exchange are mandatory for the channel bonding operation of the 2 STA may be checked.

The first STA may simultaneously transmit a radio frame to the second STA and a third STA having different channel bonding capabilities from the second STA according to at least one of OFDMA and MU-MIMO schemes. Channel unit resource region (RU) allocation information allocated to the second STA and the third STA may be informed.

The channel unit resource region allocated to the second STA and the channel unit resource region allocated to the third STA may include an overlapping channel unit resource region, and the radio frame transmitted to the second STA and the third STA The radio frame transmitted to may be distinguished through a precoding scheme.

The channel unit resource region allocated to the second STA and the channel unit resource region allocated to the third STA may be allocated to different channel unit resource regions in the frequency domain.

The first STA may transmit an RTS frame to the second STA before receiving the radio frame to the second STA, receive a CTS frame from the second STA, and use the RTS frame and the CTS frame exchange. When acquiring channel information, the radio frame may include only a preamble for the first station, a header for the first station, and a payload field.

The header for the first type STA may be a header for legacy STA prior to IEEE 802.11ay, and the header for the second type STA may be a header for STA that supports IEEE 802.11ay.

In another aspect of the present invention, a first station (STA) apparatus for transmitting a signal through channel bonding in a WLAN system, the apparatus comprising: a transceiver configured to transmit a radio frame to a second STA; And a processor configured to generate and transmit the radio frame to the transceiver, wherein the processor is configured to transmit the radio frame by channel bonding two or more channels, and transmits the radio frame using channel bonding of four channels. In this case, the first preamble and the data through the first bonding frequency region including a first frequency, a second channel and an interval frequency region corresponding to the interval between the first channel and the second channel among the four channels. And transmit the first preamble through a second bonding frequency region including a third channel, a fourth channel of the four channels, and an interval frequency region corresponding to an interval between the third channel and the fourth channel. And a station apparatus configured to repeatedly transmit the data.

According to the present invention, it is possible to provide a high throughput of channel combining while minimizing the delay thereof.

In addition, the present invention can flexibly respond to the situation of the medium for the IEEE 802.11ay standardization as described above.

1 is a diagram illustrating an example of a configuration of a WLAN system.

2 is a diagram illustrating another example of a configuration of a WLAN system.

3 is a diagram for describing a channel in a 60 GHz band for explaining a channel bonding operation according to an embodiment of the present invention.

4 is a diagram illustrating a basic method of performing channel bonding in a WLAN system.

5 is a diagram for explaining a physical configuration of an existing radio frame.

6 and 7 are views for explaining the configuration of the header field of the radio frame of FIG.

8 is a diagram illustrating a PPDU structure using gap filling according to a preferred embodiment of the present invention.

9 is a diagram illustrating a PPDU structure without using gap filling according to another embodiment of the present invention.

10 and 11 illustrate an example of an 11ay PPDU structure when four channels are bonded and used according to one embodiment of the present invention.

12 to 14 are diagrams for explaining various configurations of an EDMG header when configuring a PPDU in a gap-filling method according to an embodiment of the present invention.

15 and 16 illustrate various configurations of an EDMG header when a PPDU is configured in a manner not using gap filling according to an embodiment of the present invention.

17 and 18 are diagrams for describing a method of extending various EDMG header structures as described above with 3-4 channels.

19 illustrates a PPDU structure using gap-filling in accordance with an embodiment of the present invention.

20 is a diagram for describing a method of allocating resources to a plurality of STAs by using resource elements in units of channels according to an embodiment of the present invention.

FIG. 21 is a diagram illustrating an example in which three STAs having different channel bonding performances are allocated with a unit of resource unit according to the method described with reference to FIG.

22 and 23 illustrate a method for simultaneously supporting a legacy device and an 11ay device according to an embodiment of the present invention.

24 is a diagram for describing a method of performing multi-channel operation when STAs do not have the same FFT size according to an embodiment of the present invention.

25 illustrates a PPDU structure with the EDMG header omitted in accordance with one embodiment of the present invention.

FIG. 26 illustrates a PPDU structure in which EDMG STF and EDMG CE are omitted in accordance with one embodiment of the present invention. FIG.

FIG. 27 is a diagram for describing an apparatus for implementing the method as described above.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The detailed description, which will be given below with reference to the accompanying drawings, is intended to explain exemplary embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced.

The following detailed description includes specific details in order to provide a thorough understanding of the present invention. However, one of ordinary skill in the art appreciates that the present invention may be practiced without these specific details. In some instances, well-known structures and devices are omitted or shown in block diagram form, centering on the core functions of each structure and device, in order to avoid obscuring the concepts of the present invention.

As described above, the following description relates to a method and apparatus for transmitting data based on channel bonding in a mobile communication system. There may be various mobile communication systems to which the present invention is applied. Hereinafter, the WLAN system will be described in detail as an example of the mobile communication system.

1 is a diagram illustrating an example of a configuration of a WLAN system.

As shown in FIG. 1, the WLAN system includes one or more basic service sets (BSSs). A BSS is a set of stations (STAs) that can successfully synchronize and communicate with each other.

An STA is a logical entity that includes a medium access control (MAC) and a physical layer interface to a wireless medium. The STA is an access point (AP) and a non-AP STA (Non-AP Station). Include. The portable terminal operated by the user among the STAs is a non-AP STA, and when referred to simply as an STA, it may also refer to a non-AP STA. A non-AP STA is a terminal, a wireless transmit / receive unit (WTRU), a user equipment (UE), a mobile station (MS), a mobile terminal, or a mobile subscriber. It may also be called another name such as a mobile subscriber unit.

The AP is an entity that provides an associated station (STA) coupled to the AP to access a distribution system (DS) through a wireless medium. The AP may be called a centralized controller, a base station (BS), a Node-B, a base transceiver system (BTS), or a site controller.

BSS can be divided into infrastructure BSS and Independent BSS (IBSS).

The BBS shown in FIG. 1 is an IBSS. The IBSS means a BSS that does not include an AP. Since the IBSS does not include an AP, access to the DS is not allowed, thereby forming a self-contained network.

2 is a diagram illustrating another example of a configuration of a WLAN system.

The BSS shown in FIG. 2 is an infrastructure BSS. Infrastructure BSS includes one or more STAs and APs. In the infrastructure BSS, communication between non-AP STAs is performed via an AP. However, when a direct link is established between non-AP STAs, direct communication between non-AP STAs is also possible.

As shown in FIG. 2, a plurality of infrastructure BSSs may be interconnected through a DS. A plurality of BSSs connected through a DS is called an extended service set (ESS). STAs included in the ESS may communicate with each other, and a non-AP STA may move from one BSS to another BSS while seamlessly communicating within the same ESS.

The DS is a mechanism for connecting a plurality of APs. The DS is not necessarily a network, and there is no limitation on the form if it can provide a predetermined distribution service. For example, the DS may be a wireless network such as a mesh network or a physical structure that connects APs to each other.

Based on the above, the channel bonding method in the WLAN system will be described.

3 is a diagram for describing a channel in a 60 GHz band for explaining a channel bonding operation according to an embodiment of the present invention.

As shown in FIG. 3, four channels may be configured in the 60 GHz band, and a general channel bandwidth may be 2.16 GHz. The ISM bands available from 60 GHz (57 GHz to 66 GHz) may be defined differently in different countries. In general, channel 2 of the channels shown in FIG. 3 may be used in all regions and may be used as a default channel. Channels 2 and 3 can be used in most of the designations except Australia, which can be used for channel bonding. However, a channel used for channel bonding may vary, and the present invention is not limited to a specific channel.

4 is a diagram illustrating a basic method of performing channel bonding in a WLAN system.

The example of FIG. 4 illustrates the operation of 40 MHz channel bonding by combining two 20 MHz channels in an IEEE 802.11n system. For IEEE 802.11ac systems, 40/80/160 MHz channel bonding will be possible.

The two exemplary channels of FIG. 4 include a primary channel and a secondary channel, so that the STA can examine the channel state in a CSMA / CA manner for the primary channel of the two channels. If the secondary channel is idle for a predetermined time (e.g. PIFS) at the time when the primary channel idles for a constant backoff interval and the backoff count becomes zero, the STA is assigned to the primary channel and Auxiliary channels can be combined to transmit data.

However, when channel bonding is performed based on contention as illustrated in FIG. 4, channel bonding may be performed only when the auxiliary channel is idle for a predetermined time at the time when the backoff count for the primary channel expires. Therefore, the use of channel bonding is very limited, and it is difficult to flexibly respond to the media situation.

Hereinafter, the physical layer configuration in the WLAN system to which the present invention is applied will be described in detail.

In the WLAN system according to an embodiment of the present invention, it is assumed that three different modulation modes may be provided.

Table 1 PHY MCS anmerkung Control PHY 0 Single carrier PHY (SC PHY) 1 ... 1225 ... 31 (low power SC PHY) OFDM PHY 13 ... 24

Such modulation modes can be used to meet different requirements (eg, high throughput or stability). Depending on your system, only some of these modes may be supported.

5 is a diagram for explaining a physical configuration of an existing radio frame.

It is assumed that all DMG (Directional Multi-Gigabit) physical layers commonly include fields as shown in FIG. 5. However, there may be a difference in the method of defining individual fields and the modulation / coding method used according to each mode.

As shown in FIG. 5, the preamble of the radio frame may include a Short Training Field (STF) and a Channel Estimation (CE). In addition, the radio frame may include a header and a data field as a payload and optionally a TRN field for beamforming.

6 and 7 are views for explaining the configuration of the header field of the radio frame of FIG.

6 illustrates a case in which the SC mode is used. In the SC mode, a header indicates information indicating an initial value of scrambling, an MCS, information indicating a length of data, information indicating whether an additional PPDU is present, and a packet type. It may include information such as training length, aggregation, beam beaming request, last RSSI, truncation, and header check sequence (HCS). Also, as shown in FIG. 6, the header has 4 bits of reserved bits, and the following bits may be used in the following description.

7 shows a specific configuration of an OFDM header. The OFDM header includes information indicating the initial value of scrambling, MCS, information indicating the length of data, information indicating the presence or absence of additional PPDUs, packet type, training length, aggregation, beam beaming request, last RSSI, truncation, Information such as a header check sequence (HCS) may be included. In addition, as shown in FIG. 7, the header has 2 bits of reserved bits, and in the following description, such reserved bits may be utilized as in the case of FIG. 6.

As described above, the IEEE 802.11ay system is considering channel bonding and MIMO technology for the first time in the existing 11ad system. To implement channel bonding and MIMO in 11ay, a new PPDU structure is needed. That is, the existing 11ad PPDU structure has limitations in supporting legacy terminals and implementing channel bonding and MIMO.

To this end, a new field for a 11ay terminal may be defined behind a legacy preamble and a legacy header field to support the legacy terminal. Here, channel bonding and MIMO may be supported through the newly defined field.

In a preferred embodiment of the present invention, it is proposed to inform the bandwidth used for channel bonding through a legacy header field. This allows the ay header to contain more information bits since the new ay-header can be transmitted in bonded form.

8 illustrates a PPDU structure according to one preferred embodiment of the present invention. In FIG. 8, the horizontal axis may correspond to the time domain and the vertical axis may correspond to the frequency domain.

When two or more channels are bonded, a 400 MHz band may exist between frequency bands (1760 MHz) used in each channel. In the mixed mode, legacy preambles (legacy STFs, legacy CEs) are transmitted as duplicates through each channel. In an embodiment of the present invention, a new STF and CE are simultaneously transmitted together with the legacy preambles through a 400 MHz band between each channel. Consider gap filling.

That is, when transmitting the preambles (STF and CE) for the legacy STA through two channels having 1760 MHz, as shown in Figure 8, the GF-preamble (STF and Propose to send CE).

When the new STF and CE fields are transmitted through the 400 MHz band, the AGC, synchronization, and channel estimation for the entire frequency band used for bonding together with the legacy preamble can be performed at once. Therefore, new STF and CE fields for bonded payload transmission in 11ay do not need to exist after the legacy preamble section.

FIG. 8 illustrates a case where two channels are bonded to each other, but the present invention may be equally applied to bonding three or more channels.

In order to transmit data in the PPDU format as shown in FIG. 8, reserved bits (OFDM PHY: 2 bits, SC PHY: 4 bits) of the legacy header field may be modified to inform bandwidth used for channel bonding. Therefore, the ay header and ay Payload transmitted after the legacy header field may be transmitted through channels (2.16 + 2.16 GHz in FIG. 8) used for bonding.

As described above, since there are four channels (each 2.16 GHz) in 11ay, ay header and ay payload can be transmitted through 2.16 GHz, 4.32 GHz, 6.48 GHz, and 8.64 GHz bandwidth according to the bandwidth indicated by the legacy header field. have.

In the case of the 11ad SC PHY, the reserved bits of the legacy header field are 4 bits in total, and in the case of the 11ad OFDM PHY, 2 bits are present. Therefore, a method of informing bandwidth and channelization used for channel bonding by modifying reserved bits as shown in the following tables is proposed. This description assumes that channel bonding is a contiguous coupling between channels, but need not be limited thereto.

TABLE 2 Field name Number of bits Explanation BW (Bandwidth) 2 0: 2.16 GHz (single channel) 1: 4.32 GHz (2 channel bonding) 2: 6.48 GHz (3 channel bonding) 3: 8.64 GHz (4 channel bonding)

TABLE 3 Field name Number of bits Explanation BW (Bandwidth) 3 0: single channel 1: 2 channel bonding (ch1, ch2) 2: 2 channel bonding (ch2, ch3) 3: 2 channel bonding (ch3, ch4) 4: 3 channel bonding (ch1, ch2, ch3) 5: 3 channel bonding (ch2, ch3, ch4) 6: 4channel bonding (ch1, ch2, ch3, ch4) 7: reserved

If each terminal knows the primary channels and the channel bonding procedure is determined, like 11n / ac channel bonding method (primary / secondary channel bonding), channel bonding can be performed even if the bandwidth is only 2 bits in the legacy header as shown in Table 2. Can be.

Meanwhile, in order to apply the channel bonding procedure of 11ay only without applying the channel bonding procedure of 11n / ac, a new channelization represented by 3 bits as shown in Table 3 is preferable.

After channel bonding, the modulation method of the ay header transmitted in wide band is possible for both SC and OFDM. Legacy headers can carry 64 bits of information. If the number of bonded channels is increased to 2, 3, or 4 in the same manner, the ay header may carry 128 bits, 192 bits, and 256 bits of information in proportion to the bandwidth of the bonded channels. Alternatively, the information may be fixed to 128 bits in the ay header and the remaining bits may be used for padding with data or for increasing repetition.

Meanwhile, the PPDU format may also be considered when repetitively transmitting legacy preambles without performing the gap-filling as described above.

9 illustrates a PPDU structure according to another embodiment of the present invention. In FIG. 9, the horizontal axis may correspond to the time domain and the vertical axis may correspond to the frequency domain.

Referring to FIG. 9, the PPDU of FIG. 9 has a form of transmitting ay STF and ay CE over the legacy preamble, the legacy header, and the ay header over a wide band without performing gap-filling. In this embodiment, when channel bonding is performed, the reserved bits (OFDM PHY: 2 bits and SC PHY: 4 bits) of the legacy headers are modified to consider that ay headers are not duplicated and transmitted, but may also transmit different data. .

The PPDU format when signaling for channel bonding through the legacy header is shown in FIG. 9. 9 is a PPDU format when two-channel bonding is performed and can be expanded to three-channel and four-channel bonding.

In order to transmit data in the PPDU format as shown in FIG. 9, it is preferable to sense a frequency band used for channel bonding in Rx. The legacy preamble is received through each channel used for channel bonding, and AGC, synchronization, and channel estimation are separately performed. Therefore, different information can be sent to the ay header (a) and the ay header (b).

Modulation of the ay header is possible for both SC PHY and OFDM PHY. In case of SC PHY, x2, x3, x4 times the chip rate based on the number of channels used for channel bonding, and can transmit and receive in wide band.In the case of OFDM PHY, sampling rate and FFT size It can transmit / receive wide band by x2, x3, x4 times in proportion to the number. In the OFDM PHY, it is preferable to insert and transmit a null value in a subcarrier matching a 400 MHz band between channels.

Signaling indicating whether to send the ay header as a duplicate or different information can be reported in 1bits through the legacy header as shown in Table 4.

Table 4 Field name Number of bits Explanation Duplicate One 0: duplicate transmission for ay Header

Since 11ay has a total of four channels (each 2.16 GHz), the ay header can be transmitted through one channel, two channels, three channels, and four channels according to the bandwidth or channelization indicated by the legacy header field.

In the case of the 11ad SC PHY, the reserved bits of the legacy header field are 4 bits in total, and in the case of the 11ad OFDM PHY, 2 bits are present. Therefore, the reserved bits can be modified as shown in Table 2 and Table 3 to inform the bandwidth and channelization used for channel bonding.

If each terminal knows the primary channels and the channel bonding procedure is determined as in 11n / ac channel bonding method (primary / secondary channel bonding), channel bonding is performed even if the bandwidth is only 2 bits in the legacy header as shown in Table 2 above. can do.

Meanwhile, in order to apply the channel bonding procedure of 11ay only without applying the channel bonding procedure of 11n / ac, a new channelization represented by 3 bits is preferable as shown in Table 3 above.

Hereinafter, a method of extending channel bonding to four channels will be described based on the above description.

4-channel expansion method

When four channels are bonded, the total frequency bandwidth used for transmission and reception is 8.64 GHz. The use of 8.64 GHz of bandwidth in the 60 GHz band has many difficulties in terms of implementation and cost. Therefore, the present embodiment proposes a PPDU format for effectively bonding four channels while reducing complexity.

10 and 11 illustrate an example of an 11ay PPDU structure when four channels are bonded and used according to one embodiment of the present invention.

In detail, FIG. 10 illustrates a case where gap-filling is not performed between channels in an 11ay PPDU preamble section, and FIG. 11 illustrates a case where gap-filling is performed between channels in an 11ay PPDU preamble section. In both cases, when four channels are used for bonding, there are two two-channel bonding PPDUs (CH1 + CH2 and CH3 + CH4), and two PPDUs each have a duplicate (copy) structure.

That is, the first preamble EDMG STF and the first preamble through the first bonding frequency region including the first channel, the second channel, and the interval frequency region corresponding to the interval between the first channel and the second channel. EDMG CE) and a second bonding frequency for transmitting data (Payload) and including an interval frequency region corresponding to a third channel, a fourth channel, and an interval between the third channel and the fourth channel among the four channels. It is proposed to repeatedly transmit the same first preamble (EDMG STF and EDMG CE) and data Payload through the region.

Therefore, it is not necessary to create a new EDMG STF and EDMG CE sequence for four-channel bonding, but simply reuse the EDMG STF and EDMG CE sequences used for two-channel bonding. Similarly, the EDMG Header and Payload part can reuse the structure of 2-channel bonding. In addition, it is possible to maximize the effect of channel bonding by configuring different information in each payload.

On the other hand, the following describes whether the 11ay header transmitted through channel bonding independently configured for each channel, or whether to transmit the duplicated information.

EDMG header configuration

12 to 14 are diagrams for explaining various configurations of an EDMG header when configuring a PPDU in a gap-filling method according to an embodiment of the present invention.

Specifically, FIG. 12 shows a PPDU structure for transmitting an EDMG header in wide band using both channels. FIG. 13 shows a PPDU for transmitting EDMG header (a) and EDMG header (b) with independent information. The structure is shown. Finally, FIG. 14 shows a PPDU structure in which an EDMG header of one channel is duplicated and transmitted to the other channel.

In order to transmit data in the PPDU format as shown in FIGS. 12 to 14, the reserved bits (OFDM PHY: 2 bits, SC PHY: 4 bits) of the legacy header field may be modified to inform bandwidth and channels used for channel bonding. An indicator of an EDMG header may be added to inform bandwidth and channels used for channel bonding. Therefore, the EDMG header transmitted after the legacy header field can be transmitted in various structures as shown in FIGS. 12 to 14, and the EDMG payload is a wide band through bonding of channels (2.16 + 2.16 GHz) used for channel bonding. Can be sent to rescue.

15 and 16 illustrate various configurations of an EDMG header when a PPDU is configured in a manner not using gap filling according to an embodiment of the present invention.

Since the gap filling is not performed as shown in FIGS. 15 and 16, it is necessary to renew the channel estimation for the entire channel band used for bonding including bandwidth as much as the gap filling portion. Before that, data cannot be transmitted using this bandwidth.

FIG. 15 illustrates a PPDU structure in which EDMG headers are not duplicated and transmitted but may transmit different data. 16 shows a PPDU structure in which EDMG headers are duplicated and transmitted.

In order to transmit data in the PPDU format as shown in FIGS. 15 and 16, the reserved bits (OFDM PHY: 2 bits, SC PHY: 4 bits) of the legacy header field may be modified to inform bandwidth and channels used for channel bonding. An indicator of an EDMG header may be added to inform bandwidth and channels used for channel bonding. Therefore, the EDMG header transmitted after the legacy header field can be transmitted in various structures and contents, and the EDMG payload can be transmitted in a wide band structure through bonding of channels (2.16 + 2.16 GHz) used for channel bonding.

17 and 18 are diagrams for describing a method of extending various EDMG header structures as described above with 3-4 channels.

When four channels are bonded, the total frequency bandwidth used for transmitting and receiving is 8.64 GHz. The use of 8.64 GHz of bandwidth in the 60 GHz band has many difficulties in terms of implementation and cost. Therefore, the present embodiment proposes a PPDU format for effectively bonding four channels while reducing complexity.

FIG. 17 illustrates a case where gap-filling is not performed between channels in an 11ay PPDU preamble section, and FIG. 18 illustrates a case where gap-filling is performed between channels in an 11ay PPDU preamble section.

The contents of the EDMG Headers (a, b, c, d) of FIG. 17 may all be different or may be the same. In addition, (a = c, b = d) is possible, and (a = b, c = d) is also possible. The contents of the EDMG Headers (a, b) of FIG. 18 may also be the same or different.

When both channels use four channels for bonding, there are two two-channel bonding PPDUs (CH1 + CH2, CH3 + CH4), and the two PPDUs each have a duplicate (copy) structure.

Therefore, it is not necessary to create a new EDMG STF and EDMG CE sequence for four-channel bonding, but simply reuse the EDMG STF and EDMG CE sequences used for two-channel bonding. Similarly, the EDMG Header and Payload part can reuse the structure of 2-channel bonding. In addition, it is possible to maximize the effect of channel bonding by configuring different information in each payload.

Hereinafter, a method of efficiently obtaining channel information used for channel bonding by 11ay STAs will be described based on the above description.

Transmission of Bonding Instruction Information

19 illustrates a PPDU structure using gap-filling in accordance with an embodiment of the present invention.

If 11ay uses primary channel like 11ac, devices usually perform CCA for all channels, decode signal coming through primary channel, and transmit from L-Header or EDMG Header that informs BW. The secondary channel is not decoded until the channels used in the database are known.

19 shows a case of gap-filling a legacy preamble part. The PPDU structure can be extended to four channels, and the L-Header or the EDMG Header may not be a duplicate mode. In other words, the chip rate (1760MHz) of the 11ad channel band is used for the transmission of the existing L-STF, L-CE, and when the channel bonding, the empty frequency band (400MHz) between the channels GF-STF It is used for the transmission of GF-CE. Therefore, since the AGC and channel estimation for channel bonding are performed simultaneously in the legacy preamble section, the EDMG STF and EDMG CE, which are transmitted in wide band, are not required before the payload is transmitted.

However, if the 11ay receiving terminal decodes only the signal coming through the primary channel like 11ac, the signal coming into the secondary channel is not decoded until the field indicating the channel bonding is decoded. Therefore, when the 11ac method is applied, there is a problem that an accurate channel for channel bonding is not achieved.

In order to solve this problem, one embodiment of the present invention proposes the following four methods.

Method 1: The 11ay terminal normally performs decoding on signals from all channels.

Method 2: In case of using 11ac method, there is always a method to be preceded by RTS / DMG CTS before transmitting the PPDU with gap-filling.

Method 3: If you use 11ac method, use PPDU without gap filling.

Method 4: Use Method 2 and Method 3 dynamically together.

Applying the method 1 can be a huge burden on the processing side of the receiver. In case of Method 2, since the RTS / DMG CTS must always be preceded before sending data, the shorter the PPDU length is, the larger the overhead becomes. Method 3 has the advantage that it can be used without RTS / DMG CTS. In the case of method 4, the method 2 can be used in combination with the method 2 and 3 depending on the situation considering the environment.

Accordingly, in an exemplary embodiment of the present invention, it is assumed that a PPDU format in which a gap-filling method is not used is basically used to solve the above-mentioned problem, and unless otherwise mentioned, gap-filling is not used. It is assumed that it is explained. Meanwhile, as mentioned in Method 4, it is assumed that channel bonding indication information to be used for channel bonding is transmitted to STAs using RTC / CTS even if Gap-Filling is not used.

Specifically, in the case of method 2, when using RTS / DMG CTS, the BW required for channel bonding may be informed using reserved bits of the L-header, or may be notified through PSDU or MPDU. In addition, it can inform whether the channel bonding or DYNAMIC channel bonding in the above manner.

In 11ay, reserved bits (2 ~ 3bits) of Header of 11ad Control PHY can be used to inform bandwidth.

Table 5 Field name Number of bits Explanation BW (bandwidth) 2 0: 2.16 GHz (single channel) 1: 4.32 GHz (2 channel bonding) 2: 6.48 GHz (3 channel bonding) 3: 8.64 GHz (4 channel bonding)

Table 5 shows an example of informing bandwidth information using reserved bits 2 bits of the header of the 11ad Control PHY.

On the other hand, when not using the primary channel concept such as 11ac, as shown in Table 6 below can be used to inform the channel information using the reserved bits 3 bits of the header of the Control PHY of 11ad.

Table 6 Field name Number of bits Explanation CH (Channel) 3 0: single channel 1: 2 channel bonding (ch1, ch2) 2: 2 channel bonding (ch2, ch3) 3: 2 channel bonding (ch3, ch4) 4: 3 channel bonding (ch1, ch2, ch3) 5: 3 channel bonding (ch2, ch3, ch4) 6: 4channel bonding (ch1, ch2, ch3, ch4) 7: reserved

On the other hand, Table 7 below can inform the channel information using the reserved bits 3 bits of the header of the 11P Control PHY when using the primary channel concept such as 11ac.

TABLE 7 Field name Number of bits Explanation CH (Channel) 3 0: primary channel 1: 2 channel bonding (primary channel + secondary channel 1) 2: 2: channel bonding (primary channel + secondary channel 2) 3: 2: channel bonding (primary channel + secondary channel 3) 4: 3: channel bonding (primary channel + secondary channels 1 5: 3channel bonding (primary channel + secondary channels 1,3) 6: 3channel bonding (primary channel + secondary channels 2,3) 7: 4channel bonding (primary channel + secondary channels 1,2,3) 0: reserved

As shown in Table 7 above, if a primary channel concept such as 11ac is used, but channel bonding is available up to three channels, channel information used as shown in Table 8 below may be informed.

Table 8 Field name Number of bits Explanation CH (Channel) 2 0: primary channel 1: 2 channel bonding (primary channel + secondary channel 1) 2: 2: channel bonding (primary channel + secondary channel 2) 3: 2: channel bonding (primary channel + secondary channel 3) 4: 3: channel bonding (primary channel + secondary channels 1 ,2)

Meanwhile, an embodiment of the present invention provides a method of transmitting a frame using a plurality of channels by a channel aggregation method as a sub-concept of the above-described channel bonding or separate from the channel bonding. In the case of channel combining, the FFT size of the plurality of channels may be kept the same, and the information transmitted on each channel may be combined and used. In this case, four channels can be used more flexibly, and in order to support such channel bonding / channel combining, the reserved bits 4 bits of the header of the 11ad Control PHY are mapped to each channel to turn on each channel in a bitmap manner. You can tell on / off like this:

For example, if the reserved bits 4 bit value of the header of the 11ad Control PHY is 1100, it may indicate that channel 1 and channel 2 are used for channel bonding, and in case of 1010, channel 1 and channel 3 are used for channel combining. Can be represented.

Meanwhile, in the above description, the signaling shown in Tables 5 to 8 above is represented by using reserved bits of the header of the Control PHY of 11ad. However, the present invention is not limited thereto, and the EDMG header A or the like will be described later. It can be indicated in the same manner to any one of the EDMG header B.

In summary, in one embodiment of the present invention, it is proposed to inform a bandwidth used for channel bonding (channel combining) through a legacy header field. In this case, ay header that can include more information bits can be configured since transmission is possible in a wide band of bonding / combined form from newly added ay-header.

In addition, in the following embodiments, the PPDU format when transmitting legacy preambles as duplicates without using gap-filling is considered. When channel bonding / combination is performed, if reserved bits of legacy header (OFDM PHY: 2 bits, SC PHY: 4 bits) are modified, ay headers are not duplicated and transmitted, but different data can be sent. The PPDU format when signaling for channel bonding / combination through a legacy header is shown in FIG. 15. This structure is simply expandable to 3 channels / 4 channels as described above.

In order to transmit data in the PPDU format as shown in FIG. 15, the frequency band used for channel bonding / combining in Rx must be sensed. Since legacy preamble is received through each channel used for channel bonding / combining, and AGC, synchronization, and channel estimation are performed separately, different information can be sent to ay Header (a) and ay Header (b).

As described above, the modulation of the ay header is possible for both the SC PHY and the OFDM PHY. In the case of SC PHY, the chip rate is x2, x3, and x4 in proportion to the number of channels used for channel bonding, and both the method of transmitting and receiving in wide band and the x1 times of the legacy header are possible.

In the case of OFDM PHY, there is a method of transmitting and receiving in wide band by multiplying sampling rate and FFT size by x2, x3, and x4 in proportion to the number of channels used for channel bonding. To this end, it is preferable to insert and transmit a null value in a subcarrier matching the 400 MHz band between each channel. In addition, like the SC PHY, up to ay Header can be all the same way of x1 as legacy Header.

After channel bonding, the modulation method of the ay header transmitted in wide band is possible for both SC and OFDM. In the case of legacy header, 64 bits of information can be loaded. In the same way, if the number of bonded channels is increased to 2, 3, or 4, the ay header can carry 128 bits, 192 bits, and 256 bits of information in proportion to the bandwidth of the bonded channels. Alternatively, the information may be fixed to 128 bits in the ay header, and the remaining bits may be padded with data or increased repetition.

Meanwhile, since more information can be loaded in the ay header, the 802.11ay PPDU format can support MIMO in a PPDU format in which only one ay-header field exists.

Regardless of whether Gap-filling is applied or not, the receiver decodes the incoming signal through all channels, or when the receiver knows the channels needed for bonding, preceded by the RTS / DMG CTS, the legacy header indicates that channel bonding is performed. Different channels may have different information. Then, for example, different MCS indicators can be included in the EDMG header for each channel so that different MCS can be used for each channel according to the channel state.

MU-MIMO / OFDMA application method

As described above, the IEEE 802.11ay system considers the introduction of channel bonding and MIMO technology. In addition, unlike IEEE 802.11ad, various technologies are being considered to enable communication in various environments such as indoors, outdoor, and dense environments. Among them, MU-MIMO is effective in dense environment. In the dense environment, when channel bonding ability is different for each STA or channel bandwidth for data reception is different, flexible communication is possible by assigning different channels or bandwidths for data transmission and reception for each STA in downlink MU-MIMO situation. The improvement in performance can be achieved.

In the following embodiment, consider an environment considering OFDMA, channel bonding, and MU-MIMO simultaneously in 11ay. According to an embodiment of the present invention, STAs are allocated a BW for transmitting a frame by using a resource unit of a channel unit for a total of four channels. In addition, it is proposed that STAs using the same frequency band receive desired data through MIMO.

20 is a diagram for describing a method of allocating resources to a plurality of STAs by using resource elements in units of channels according to an embodiment of the present invention.

In detail, FIG. 20 illustrates an example in which OFDMA, channel bonding, and MU-MIMO are simultaneously considered in 11ay. During the same time, STA a, STA b, and STA c may be simultaneously allocated different frequency resources by the OFDMA scheme, and STA d may receive and receive the overlapping frequency resources by the MU-MIMO scheme. That is, STA d may be allocated by using the same channel by using precoding that may be distinguished from STA a / b / c.

FIG. 21 is a diagram illustrating an example in which three STAs having different channel bonding performances are allocated with a unit of resource unit according to the method described with reference to FIG.

In detail, FIG. 21 illustrates a PPDU format when allocating BWs corresponding to three channels to three STAs by applying OFDMA MU-MIMO. When the OFDMA scheme is applied, RUs (channels or bandwidth) allocated to each STA may be informed through the EDMG Header A.

Channel assignment via EDMA header A is as shown in the above tables.

In addition, by applying the OFDMA scheme, different STAs may be supported for different STAs. The EDMG Header A may inform the MCS differently for each STA. Alternatively, this may be indicated through EDMG Header B.

In consideration of OFDMA and MIMO simultaneously, the MCS may be informed differently for each STA through the EDMG Header B.

Support for 11ad Legacy Devices and 11ay Devices Simultaneously

As mentioned above, 11ay considers bonding up to four channels or using them simultaneously. Accordingly, a device that does not support channel bonding or an 11ay device that does or does not channel bond depending on the situation may exist in the system.

The following embodiment proposes a PPDU for simultaneously supporting 11ad legacy devices and 11ay devices in such a situation.

22 and 23 illustrate a method for simultaneously supporting a legacy device and an 11ay device according to an embodiment of the present invention.

Specifically, FIG. 22 and FIG. 23 show PPDUs supporting 11ad legacy devices and 11ay devices simultaneously when using three channels. Up to four channels can be expanded simultaneously, and the primary channel can be one of them. Also, EDMG Header B for 11ay can be omitted unless it supports MU-MIMO.

22 and 23, in order to actually implement, add a process of negotiating channel bonding between PCP / AP and STA or which channel to use in advance, or assigning channels for each STA by using RTS and DGM CTS. It is desirable to do it.

By using reserved bits in the header of the Control PHY PPDU format or using reserved bits in the MPDU can be informed to the 11ay STA, the 11ad legacy terminal can receive the incoming signal through the channel used by itself as the existing 11ad.

Since 11ay considers using several channels at the same time, it is desirable to have a process of negotiating channel bonding between PCP / AP and STA or how much channel to use when exchanging beacon frames or frames for association. Do. This can be done using the 11ad control PHY PPDU. The reserved bits in the header of the Control PHY PPDU format may be used or the reserved bits in the MPDU may be modified to inform the information about the channel or the channel width.

In addition to the capability negotiation for the channel, the capability negotiation for the power consumption capability can be informed at the same time. A device with a high power consumption can decode all signals coming in through channels corresponding to its channel bonding capability in a non-sleep mode. This performance can be determined when sending and receiving initial beacon frames or frames for associations.

Through the association or negotiation process performed before actual data is transmitted and received as described above, STAs can individually request the PCP / AP to use RTS / DMG CTS. The requested PCP / AP may accept the request and mandatory use of the STA and RTS / DMG CTS, or may reject and use the RTS / DMG CTS as an option. It is possible to support flexible multi-channel operation when multiple channels are used simultaneously through channel bonding or information on how much channel to use or power consumption in RTS / DMG CTS.

24 is a diagram for describing a method of performing multi-channel operation when STAs do not have the same FFT size according to an embodiment of the present invention.

One embodiment of the present invention proposes to add an indicator indicating a multi-channel operation or OFDMA in the L-Header by modifying reserved bits.

In EDMG Header A, it is proposed to inform the channel and bandwidth allocated for each STA by the same method as the MU-MIMO and OFDMA signaling proposed above. When signaling in this manner, even if the FFT size or channel bonding capability is different for each STA, data can be simultaneously transmitted to several STAs.

As shown in FIG. 24, CH2 and CH3 may be used as guard to remove interference. The number of channels can be extended up to four, and the number of STAs can be up to four. In addition, depending on the situation, the RU allocated per STA may vary. EDMG Header B can be omitted if necessary.

How to minimize signaling overhead

25 illustrates a PPDU structure with the EDMG header omitted in accordance with one embodiment of the present invention.

In the above multi-channel operation, the PPDU structure for the 11ay terminal may omit and transmit the EDMG Header A as shown in FIG. 25, and may instead perform signaling for the 11ay terminal using reserved bits of the L-Header. . In addition, the channel and the BW allocated to the 11ay terminal may be informed using the reserved bits. In addition, 11ay and 11ad may be different from each other in MCS by using reserved bits.

FIG. 26 illustrates a PPDU structure in which EDMG STF and EDMG CE are omitted in accordance with one embodiment of the present invention. FIG.

When using the RTS / DMG CTS, it is possible to know the information about the BW allocated to it in advance, so that the PPDU structure can be designed without EDMG STF or EDMG CE as shown in FIG. In addition, if the 11ay UE can always decode the signal in the band corresponding to the BW corresponding to its channel bonding capability at all times, this also can design the PPDU structure without EDMG STF or EDMG CE.

When using the RTS / DMG CTS, as a signaling method for implementing the above PPDU structure, the BW information allocated to the 11ay terminal through the L-Header in the RTS / DMG CTS and additional information on the PPDU structure can be informed as necessary. have. Alternatively, in case of a PPDU for simultaneously supporting 11ay and legacy using RTS / DMG CTS on the 11ay standard, it may be specified that the structure is used as shown in FIG. 26 above.

Table 9 and Table 10 below show how to use reserved bits (3 bits) of the L-Header.

Table 9 Field name Number of bits Explanation CH (Channel) 3 0: ch11: ch22: ch33: ch44: 2channel bonding (ch1, ch2) 5: 2channel bonding (ch2, ch3) 6: 2channel bonding (ch3, ch4) 7: reserved

Table 10 Field name Number of bits Explanation Legacy Format One 0: 11ay PPDU format CH (Channel) 2 0: ch11: ch22: ch33: ch4

Let's look at the field called legacy format in Table 10 above. If 0, the PPDU structure of the channel used by 11ay may be added with EDMG STF, EDMG CE, EDMG Header A, EDMG Header B, etc. in front of the payload. If necessary, only EDMG Header A may be added to signal only for 11ay terminal, and others may be added or not depending on the situation. If 1, the PPDU structure of the channel used by 11ay is the same as that of the 11ad PPDU structure. In this case, the 11ay terminal may reuse the information of the L-Header.

Since Legacy 11ad does not support channel bonding, data is transmitted and received only through one channel agreed in advance. Therefore, primary channel should always be assigned to legacy 11ad. (This is true when legacy and 11ay coexist.)

Although 4 channel bonding is supported as a whole in 11ay system, device-specific channel bonding can be changed according to physical environment or technical situation. Table 11 below shows an example of the BW field design of the EDMG header A of the RTC / CTS frame.

Table 11 Field name Number of bits Explanation BW (Bandwidth) 4 0: ch11: ch22: ch33: ch44: 2channel bonding (ch1, ch2) 5: 2channel bonding (ch2, ch3) 6: 2channel bonding (ch3, ch4) 7: 2channel bonding (ch1, ch3): aggregation8: 2channel bonding ( ch2, ch4): aggregation9: 2channel bonding (ch2, ch4): aggregation10: 3channel bonding (ch1, ch2, ch3) 11: 3channel bonding (ch2, ch3, ch4) 12: 4channel bonding (ch1, ch2, ch3, ch4) 13-15: reserved

FIG. 27 is a diagram for describing an apparatus for implementing the method as described above.

The wireless device 800 of FIG. 27 may correspond to a specific STA of the above description, and the wireless device 850 may correspond to the PCP / AP of the above description.

The STA 800 may include a processor 810, a memory 820, and a transceiver 830, and the PCP / AP 850 may include a processor 860, a memory 870, and a transceiver 880. can do. The transceiver 830 and 880 may transmit / receive a radio signal and may be executed in a physical layer such as IEEE 802.11 / 3GPP. The processors 810 and 860 are executed at the physical layer and / or MAC layer, and are connected to the transceivers 830 and 880. Processors 810 and 860 may perform the aforementioned UL MU scheduling procedure.

Processors 810 and 860 and / or transceivers 830 and 880 may include application-specific integrated circuits (ASICs), other chipsets, logic circuits and / or data processors. The memories 820 and 870 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media and / or other storage units. When an embodiment is executed by software, the method described above can be executed as a module (eg, process, function) that performs the functions described above. The module may be stored in the memory 820, 870 and executed by the processors 810, 860. The memories 820 and 870 may be disposed inside or outside the processes 810 and 860 and may be connected to the processes 810 and 860 by well-known means.

The detailed description of the preferred embodiments of the invention disclosed as described above is provided to enable any person skilled in the art to make and practice the invention. Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will understand that the present invention can be variously modified and changed from the above description. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

As described above, the present invention has been described assuming that it is applied to an IEEE 802.11-based WLAN system, but the present invention is not limited thereto. The present invention can be applied in the same manner to various wireless systems capable of data transmission based on channel bonding.

Claims (15)

A method for transmitting a signal through channel bonding by a first station (STA) in a WLAN system, The first STA transmits a radio frame to the second STA, The radio frame transmits two or more channels by channel bonding, In case of transmitting the radio frame using channel bonding of 4 channels, Transmitting a first preamble through a first bonding frequency region including a first channel, a second channel of the four channels, and an interval frequency region corresponding to the interval between the first channel and the second channel, Transmitting the first preamble repeatedly through a second bonding frequency region including a third channel, a fourth channel, and an interval frequency region corresponding to an interval between the third channel and the fourth channel among the four channels. , Signal transmission method. The method of claim 1, The first preamble includes a Short Training Field (STF) and a Channel Estimation (CE) field. In the case of transmitting the radio frame using four channels of channel bonding, a two-channel bonding STF sequence and a CE sequence are used. The method of claim 1, The first STA sequentially transmits preamble information for a first type STA, a header for a first type STA, and a header for a second type STA through the first channel and the second channel, respectively. And transmitting the first preamble as a preamble for a second type STA through the first bonding frequency domain. The method of claim 3, wherein The header for the first type STA includes duplicated information whether the header for the second type STA transmitted through the first channel and the header for the second type STA transmitted through the second channel include independent information. And information about whether the signal is transmitted. The method of claim 3, wherein One of the header for the first type STA and the header for the second type STA includes bonding indication information indicating which of the first to fourth channels will be used for channel bonding. The method of claim 5, The second STA attempts to receive only a channel corresponding to a primary channel among the first to fourth channels until the bonding indication information is received. The method of claim 3, wherein The first STA transmits an RTS frame to the second STA before receiving the radio frame using channel bonding, receives a CTS frame from the second STA, Wherein the RTS frame and at least one of the CTS frames include bonding indication information indicating which of the first to fourth channels is to be used for channel bonding. The method of claim 1, If the radio frame supports one or more of MU-MIMO or OFDMA, the first preamble includes an Enhanced Directional Multi-Gigabit (EDMG) header A and an EDMG header B, If the radio frame does not support the MU-MIMO and the OFDMA, the first preamble does not include the EDMG header B. The method of claim 1, Before the first STA transmits the radio frame to the second STA, the first STA performs a performance negotiation process through a beacon frame or a frame exchange for association. And identifying one or more of information on channel bonding capability, power consumption capability, and whether RTC and CTS frame exchange for channel bonding operation is mandatory in the performance negotiation process. The method of claim 8, The first STA simultaneously transmits a radio frame to the second STA and a third STA having different channel bonding capabilities from the second STA according to at least one of OFDMA and MU-MIMO schemes.  The EDMG header A informs channel unit resource region (RU) allocation information allocated to the second STA and the third STA. The method of claim 10, The channel unit resource region allocated to the second STA and the channel unit resource region allocated to the third STA include an overlapping channel unit resource region, The radio frame transmitted to the second STA and the radio frame transmitted to the third STA are distinguished through a precoding scheme. The method of claim 10, The channel unit resource region allocated to the second STA and the channel unit resource region allocated to the third STA are allocated to different channel unit resource regions in the frequency domain. The method of claim 1, The first STA transmits an RTS frame to the second STA before transmitting the radio frame to the second STA, receives a CTS frame from the second STA, When acquiring channel information used through the RTS frame and the CTS frame exchange, the radio frame includes only a preamble for a first station, a header for the first station, and a payload field. The method of claim 3, wherein The header for the first type STA is a header for legacy STA before IEEE 802.11ay, The header for the second type STA is a header for a STA that supports IEEE 802.11ay. In a first station (STA) apparatus for transmitting a signal through channel bonding in a WLAN system, A transceiver configured to transmit a radio frame to a second STA; And A processor for generating the radio frame and delivering the radio frame to the transceiver; The processor is configured to transmit the radio frame by channel bonding two or more channels, and when the radio frame is transmitted using channel bonding of four channels, the first channel, the second channel, and the four channels. Transmitting a first preamble and data through a first bonding frequency region including an interval frequency region corresponding to an interval between the first channel and the second channel, wherein the third, fourth, and And repeatedly transmit the first preamble and the data over a second bonding frequency region comprising an interval frequency region corresponding to the interval between the third channel and the fourth channel.

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