WO2011145811A2 - Apparatus and method for transceiving data in a wireless lan system - Google Patents

Abstract

According to one embodiment of the present invention, a transmission method includes: receiving a TXVECTOR, including information on a packet to be transmitted, from a medium access control (MAC) layer; checking a format parameter of the received TXVECTOR; inspecting a channel bandwidth parameter and channel offset parameter of the TXVECTOR according to the checked format parameter; and transmitting a packet that is generated based on the checked format and the inspected channel bandwidth and channel offset.

Description

Apparatus and method for transmitting / receiving data in wireless LAN system

The present invention relates to a wireless communication system using a TV white space, and more particularly, to an apparatus and a method for improving data transmission efficiency in a wireless LAN system.

Currently, the television broadcasting service is moving from analog broadcasting to digital broadcasting. This is because digital broadcasting can provide high quality video and two-way services and use spectrum more efficiently.

This transition to digital broadcasting provides an idle frequency band that can be used by any of the VHF (Very High Frequency, 54 MHz to 88 MHz) band and the UHF (Ultra High Frequency, 174 MHz to 698 MHz) band allocated for the conventional analog broadcasting. An example of such an idle frequency band is a TV white space (hereinafter referred to as TVWS).

That is, TVWS means an empty frequency band not used by broadcasters in the VHF and UHF frequency bands distributed for TV broadcasting, and is an unlicensed frequency band that anyone can use when the conditions for government radio regulations are satisfied. If a licensed device is not in use in this unlicensed frequency band, it is possible for an unlicensed device to use the band.

For example, on November 4, 2008, the Federal Communications Commission (FCC) approved the frequencies of the VHF and UHF bands used by DTV as unlicensed bands that anyone could use if they met regulatory requirements set by the FCC.

In addition, as shown in Figure 1, the FCC is a non-licensed device, such as a wireless LAN, when there is no licensed device, such as a TV signal, a wireless microphone, in the remaining TV channels except the 37 channels of the TV channels Regulations are underway to enable the TV channels to be used. In accordance with the US FCC's policy, other countries are developing corresponding policies and regulations on TV white space.

In addition, various wireless communication systems are being developed for using the TVWS, and the IEEE (Institute of Electrical and Electronics Engineers) 802.11 Working Group uses a wireless local area network (WLAN) system using TVWS as an 802.11af standard. The development is in progress.

The present invention is compatible with the existing wireless LAN system, and provides an apparatus and method for effectively transmitting and receiving data using different TV frequency bands for different countries.

In addition, the present invention provides a new transmission format frame for transmitting and receiving data in a full-band wireless LAN system.

The present invention also provides a transmission and reception apparatus and a method for performing a high throughput (HT) operation of IEEE 802.11n in a wireless LAN system using a TV white space band.

The present invention provides a wireless LAN apparatus for performing a high throughput (HT) operation using a TV white space band, the method comprising: receiving a TXVECTOR from a medium access control (MAC) layer including information on a packet to be transmitted; Checking a format parameter of the received TXVECTOR; Examining a channel bandwidth parameter and a channel offset parameter of the TXVECTOR according to the identified format parameter; And transmitting a packet formed based on the checked format and the checked channel bandwidth and channel offset.

In addition, the present invention is a wireless LAN device for performing a high throughput (HT) operation using a TV white space band, PHY for receiving a TXVECTOR including information on the packet to be transmitted from the medium access control (MAC) unit Service interface; A controller for checking a format parameter of the TXVECTOR received from the PHY service interface and checking a channel bandwidth and a channel offset of the TXVECTOR according to the identified format parameter; And a PHY unit for transmitting a packet formed based on the checked format and the checked channel bandwidth and channel offset.

The present invention also provides a wireless LAN apparatus for performing a high throughput (HT) operation using a TV white space band, the method comprising: receiving an RXVECTOR from a physical layer including information on a received packet; Checking a format parameter of the received RXVECTOR; Checking a channel bandwidth parameter of the RXVECTOR according to the identified format parameter; And analyzing the received packet using the identified format and the checked channel bandwidth.

The present invention also provides a PHY service interface for receiving an RXVECTOR from a physical layer including information on a received packet in a receiving apparatus of a wireless LAN apparatus for performing a high throughput (HT) operation using a TV white space band. ; A controller for checking a format parameter of the RXVECTOR received from the PHY service interface and checking a channel bandwidth parameter of the RXVECTOR according to the identified format parameter; And a medium access control (MAC) unit for analyzing the received packet using the checked format and the checked channel bandwidth.

According to an embodiment of the present invention, transmission efficiency may be improved by improving an inefficient bandwidth usage problem that occurs when a different TV white space channel is applied to each country in an existing wireless LAN system. In addition, when the existing wireless LAN system is operating on the TV white space channel to be used can provide a new wireless LAN system that can operate in a mode compatible with the existing wireless LAN system.

In addition, according to another embodiment of the present invention, wireless LAN devices operating in a TV white space perform a high throughput (HT) operation defined in IEEE 802.11n as well as a channel bandwidth of 20 MHz and 40 MHz, as well as a channel of 5 MHz and 10 MHz. It can also run on bandwidth.

On the other hand various other effects will be disclosed directly or implicitly in the detailed description of the embodiments of the present invention to be described later.

1 is a channel map showing a US TV band and a band in which a W-LAN device can operate;

2 is a diagram illustrating channel allocation of a WLAN system according to a channel bandwidth of a TV white space;

3 illustrates two methods of defining a channel of a WLAN system in a TV white space band;

4 is a diagram illustrating three types of frame structures used in a wireless LAN device according to an embodiment of the present invention;

5 to 8 illustrate the FB-STF pattern in the frequency domain according to an embodiment of the present invention;

9 and 10 are diagrams illustrating a FB-LTF pattern in a frequency domain according to an embodiment of the present invention;

11 is a view schematically showing the configuration of a wireless LAN device according to an embodiment of the present invention;

12 is a block diagram of a transmitting device for transmitting a frame in an existing wireless LAN system.

13 is a block diagram of a transmitter for generating a control signal in an existing wireless LAN system;

14 is a diagram illustrating an example of a transmitting device for transmitting a frame in an FB WLAN system according to an embodiment of the present invention;

15 is a diagram illustrating another example of a transmission device for transmitting a frame in an FB WLAN system according to one embodiment of the present invention;

FIG. 16 is a diagram illustrating a procedure of transmitting a frame by the transmitting apparatus of FIG. 15; FIG.

17 is a view showing an example of a receiving apparatus for receiving a frame in an FB wireless LAN system according to an embodiment of the present invention;

18 is a diagram illustrating a procedure of receiving a frame by the receiving device of FIG. 17;

19 is a block diagram of a receiving apparatus including a frequency tracking loop for channel compensation in an FB WLAN system according to an embodiment of the present invention;

20 is a view showing another example of a receiving apparatus for receiving a frame in an FB WLAN system according to an embodiment of the present invention;

21 is a view showing another example of a receiving apparatus for receiving a frame in an FB WLAN system according to an embodiment of the present invention;

22 is a diagram illustrating a procedure of receiving a frame by the receiving device of FIG. 21;

FIG. 23 is a diagram illustrating a relationship between a medium access control (MAC) layer and a physical layer in the WLAN apparatus of FIG. 11; FIG.

FIG. 24 is a flowchart illustrating a procedure of performing HT operation and non-HT operation in a 5 MHz channel and a 10 MHz channel using a TXVECTOR input to the PHY service interface of FIG. 23; FIG.

FIG. 25 is a flowchart illustrating a procedure of performing an HT operation and a non-HT operation on a 5 MHz channel and a 10 MHz channel by using an RXVECTOR input to the PHY service interface of FIG. 23. FIG.

In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

In general, a wireless LAN system performs communication using a channel bandwidth of 5/10/20 / 40MHz in a 2.4GHz band or a 5GHz band. However, the available channel bandwidth in the TV white space band varies by region and / or country, for example, 6/7/8 MHz may be used depending on the region. As described above, since the channel allocation unit in the WLAN system and the channel allocation unit in the TV white space are different from each other, there is a problem that the frequency efficiency is lowered when the WLAN system uses the TV white space.

For example, as shown in FIG. 2, in the United States, since the channel bandwidth of the TVWS is allocated in units of 6 MHz, in order to use the TVWS in a wireless LAN system, it is inevitable to have a frequency utilization rate of 5/6. The frequency utilization rate is the same even when the channel bandwidth of each wireless LAN system is 5/10 / 20MHz. In addition, such inefficiency of frequency utilization occurs even when the channel bandwidth of TVWS is 7 MHz or 8 MHz.

In order to solve this problem, an embodiment of the present invention provides a method for transmitting and receiving data by using a TV frequency band that is compatible with existing wireless LAN systems while being different from country to country.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

4 illustrates three types of frame structures used in a wireless LAN device according to an embodiment of the present invention. Here, the wireless LAN device may transmit and receive data using any one of the three types of frames.

Referring to FIG. 4, three types of frames used by the WLAN apparatus are legacy-format frame 410, FB-only-format frame 420, and FB mixed format frame. (FB-mixed-format frame, 430). Here, the legacy format frame 410 is a frame structure used in the existing WLAN system. The FB dedicated format frame 420 and the FB mixed format frame 430 are newly defined frame structures for efficiently using TVWS channel bandwidth.

Meanwhile, in the following embodiment, a wireless LAN system capable of transmitting any format frame among the three types of frames is referred to as a "full band (hereinafter referred to as" FB ") wireless LAN system", and A WLAN system transmitting only legacy format frames defined in IEEE 802.11 will be referred to as an existing WLAN system.

First, when the WLAN system does not use the TV white space band, the FB WLAN system may communicate using the same legacy format frame 410 as the existing WLAN system.

At this time, the legacy format frame 410 used by the FB WLAN system is the same as the frame structure transmitted in the channel bandwidth of A MHz in the existing WLAN system. Here, the A MHz bandwidth may be any one of channel bandwidths of 5 MHz, 10 MHz, 20 MHz, and 40 MHz, which are channel bandwidths used by the existing WLAN system.

The legacy format frame 410 includes a short training field (hereinafter referred to as 'STF'), a long training field (hereinafter referred to as 'LTF'), a signal field and a data field ( Data Field).

The STF may be used to detect the beginning of the legacy format frame 410 at the receiving end and to set auto gain control. In addition, the STF may be used to obtain initial frequency and time synchronization at the receiving end.

In addition, the STF has a length corresponding to twice (2T _SYM ) a symbol period of Orthogonal Frequency Division Multiplexing (OFDM) in the time domain.

The LTF may be used for channel estimation and may be used to obtain more accurate frequency and time synchronization than the STF. In addition, the LTF has a length corresponding to twice the OFDM symbol period (2T _SYM ) in the time domain.

The signal field includes rate information and length information, and has a length corresponding to one OFDM symbol period T _SYM in the time domain. Here, the rate information includes information about a modulation scheme and a coding rate of a frame to be transmitted, and the length information includes information about the amount of data stored in the frame.

The data field includes N data symbol streams and has a length corresponding to one OFDM symbol period T _{SYM for} each data symbol.

Meanwhile, in the time domain, the T _SYM is one OFDM symbol period, which is equal to the effective OFDM symbol period T _{eff_SYM plus} the length of the guard interval TCP. The OFDM symbol period T _SYM may be determined according to the channel bandwidth (A MHz), the FFT size (Fast Fourier Transform Size), and the guard interval (Guard Interval) length of the existing WLAN system. At this time, the FFT size and the length of the guard interval are not limited thereto. However, in the following embodiment, for convenience of description, it is assumed that the length of the guard interval is 1/4 of the effective OFDM symbol period T _{eff_SYM} .

For example, it is assumed that a channel bandwidth of IEEE 802.11 is 5 MHz, an FFT size is 64, and a length of a guard interval corresponds to 1/4 of an effective OFDM symbol period. In this case, the subcarrier spacing (ΔF) is a value obtained by dividing the number of subcarriers (= FFT size) by the channel bandwidth and having a 78.125 (= 5000/64) KHz value. Since the period T _SYM of the OFDM symbol corresponds to the inverse T _SYM = 1 / ΔF of the subcarrier spacing ΔF, the OFDM symbol has a value of 12.8 μs (= 1 / 78.125 × 103). Accordingly, the period T _SYM of the OFDM symbol may be determined according to the channel bandwidth and the FFT size of the WLAN system, and the effective OFDM symbol period T _{eff_SYM} may be calculated according to the length of the guard period.

On the other hand, when it is not necessary to be compatible with the existing WLAN system, that is, when using only the frequency resources of the TVWS band, the FB WLAN system may transmit the FB dedicated format frame 420 in consideration of the efficiency of the frequency resources. .

The FB dedicated format frame 420 is a frame of a new structure transmitted with a TVWS channel bandwidth of B MHz. Here, the B MHz bandwidth may be any one of channel bandwidths corresponding to the channel bandwidth of the TVWS or an integer multiple of the channel bandwidth determined according to the region, but is not limited thereto. For example, in the United States, the B MHz bandwidth may be any one of channel bandwidths (12 MHz, 18 MHz, ...) corresponding to a channel bandwidth of 6 MHz and an integer multiple of the 6 MHz.

The FB dedicated format frame 420 includes an FB-STF, an FB-LTF, an FB-SIG field, and an FB-DATA field. In the FB dedicated format frame 420, the role played by the FB-STF, FB-LTF, and FB-SIG fields is similar to the role played by the corresponding field of the legacy format frame 410. The description is omitted. Therefore, the following description will focus on differences between the legacy format frame 410 and the FB dedicated format frame 420.

The length of the FB-STF may have a length corresponding to one OFDM symbol period T ' _SYM or a length corresponding to two times 2T' _SYM of the OFDM symbol period according to the FFT size. For example, when the FFT size of the FB dedicated format frame 420 is 256, the length of the FB-STF is defined as twice T ' _SYM (2T' _SYM ), and when the FFT size is 512, the FB The length of -STF can be defined as T ' _SYM .

The FB-LTF is disposed after the FB-STF and has a length corresponding to one OFDM symbol period T ' _SYM . On the other hand, as shown in Figure 4, when using a multiple-antenna (Multiple-Input Multiple-output (MIMO)) scheme in the FB wireless LAN system, the FB dedicated format frame 420 is one It contains M FB-LTFs that are not FB-LTFs. Here, M means the number of transmit antennas. Accordingly, the FB dedicated format frame 420 may include FB-LTF1 disposed after the FB-STF and FB-LTF2 to FB-LTFM disposed after the FB-SIG field.

The FB-SIG field is arranged after the FB-LTF, and has a length corresponding to one OFDM symbol period T ' _SYM .

The FB-DATA field may be disposed after the FB-SIG field when the MIMO technique is not applied, and after the FB-LTFM when the MIMO technique is applied. The FB-DATA field includes N data symbol streams and has a length corresponding to one OFDM symbol period T _{SYM for} each data symbol.

Meanwhile, as described above, in the time domain, the T ' _SYM is one OFDM symbol period and depends on the TVWS channel bandwidth (B MHz), FFT size (Fast Fourier Transform Size), and guard interval (Guard Interval) length. Can be determined. At this time, the FFT size and the length of the guard interval are not limited thereto.

Meanwhile, in order to be compatible with an existing WLAN system and increase transmission efficiency, the FB WLAN system may transmit the FB mixed format frame 430. The FB mixed format frame 430 is a frame having a new structure in which a legacy format frame 415 of A MHz and an FB format frame 425 of B MHz are combined.

The legacy format frame 415 of the FB mixed format frame 430 includes an STF, LTF, signal field, and FB-SIG field. Here, the STF and the LTF have a length corresponding to twice (2T _SYM ) one OFDM symbol period in the time domain. The signal field and the FB-SIG field have a length corresponding to one OFDM symbol period T _SYM in the time domain.

The FB format frame 425 of the FB mixed format frame 430 includes FB-STF, FB-LTF, and FB-DATA fields. Meanwhile, as shown in FIG. 4, when the MIB scheme is used in the FB WLAN system, the FB format frame 425 includes M FB-LTFs instead of one FB-LTF. In addition, each of FB-STF, FB-LTF ₁ ,..., FB-LTF _M , FB-DATA ₁ , ...., FB-DATA _{N of} the FB format frame 425 has one OFDM symbol period. It has a length corresponding to (T ' _SYM ).

The three types of frame structures described above are frame structures determined according to TVWS channel bandwidth (B MHz) predetermined in each country and / or region and operating bandwidth (A MHz) of the existing WLAN system.

For example, in the United States, when the existing wireless LAN system uses a 5MHz bandwidth in the TVWS channel band of 6MHz, three types of frame structure, A = 5, B = 6 may be formed. In addition, in the 12 MHz channel band composed of two TVWS channels, when the existing wireless LAN system uses the 10 MHz bandwidth, three types of frame structures A = 10 and B = 12 may be formed.

Meanwhile, the FB WLAN system defines some or all of the OFDM symbols constituting the transmission frame according to the TVWS channel bandwidth, and uses an FFT size larger than the FFT size of the existing WLAN system, thereby providing a long data packet. Efficient transmission

In more detail, if the length of the data packet is long enough even if the period of the OFDM symbol and the period of the preamble is increased by increasing the FFT size, the increase of the overhead may be limited. In contrast, the increase in the FFT size narrows the sub-carrier spacing in the frequency domain, causing the edges of the transmission spectrum to fall to larger slopes, so that a relatively small number is needed to satisfy the transmission spectrum mask. Null-tones are required. Therefore, increasing the size of the FFT enables signal transmission in a wider frequency band while satisfying the transmission spectrum mask, thereby improving data transmission efficiency.

5 to 8 are diagrams illustrating an FB-STF pattern in a frequency domain according to an embodiment of the present invention. 5 illustrates an FB-STF pattern defined as a real signal when the FFT size is 256, and FIG. 6 illustrates an FB-STF pattern defined as a complex signal when the FFT size is 256. 7 illustrates an FB-STF pattern defined as a real signal when the FFT size is 512, and FIG. 8 illustrates an FB-STF pattern defined as a complex signal when the FFT size is 512.

5 and 6, when the FFT size is 256, the FB-STF pattern includes a total of 256 subcarriers in the frequency domain. The total number of subcarriers constituting the FB-STF pattern is equal to the sum of the number of effective subcarriers and the number of null tones. Here, the effective subcarriers mean subcarriers used for actual frame transmission, and the null tones mean subcarriers not used for frame transmission. The null tones include DC tones and guard subcarriers. For example, the FB-STF pattern illustrated in FIGS. 5 and 6 may be configured with a total of 256 subcarriers including 234 effective subcarriers and 22 null tones.

7 and 8, when the FFT size is 512, the FB-STF pattern includes a total of 512 subcarriers in the frequency domain. The total number of subcarriers constituting the FB-STF pattern is equal to the sum of the number of effective subcarriers and the number of null tones. For example, the FB-STF pattern illustrated in FIGS. 7 and 8 may be configured with a total of 512 subcarriers including 492 effective subcarriers and 20 null tones.

The FB-STF pattern is configured such that the same pattern is repeated several times in a time domain of an OFDM symbol period including a guard period (or a cyclic prefix (hereinafter, referred to as 'CP')). Make it easy to get motivation.

In addition, the FB-STF pattern provides a low peak-to-average power ratio (PAPR) characteristic, even if the power gain is not automatically adjusted by the RF front end unit of the receiver. Ensure that the signal characteristics of the STF pattern are consistent.

To provide this function, as shown in Figs. 5 and 6, when the FFT size is 256, the FB-STF is the same pattern 20 times for two OFDM symbol periods (2T ' _SYM ) in the time domain It can be designed to be a repeating form. Here, since the same pattern is repeated 20 times during two OFDM symbol periods 2T ' _SYM , the same pattern is repeated 10 times during one OFDM symbol period T' _SYM .

As described above, one OFDM symbol period T ' _SYM corresponds to a value obtained by adding the length of the guard period TCP to the effective OFDM symbol period T' _{eff_SYM} , and the length of the guard period TCP is It corresponds to one quarter of the effective OFDM symbol period T ' _{eff_SYM} . Thus, one OFDM symbol period, the same pattern during "valid OFDM symbol period (T a _{(SYM eff_SYM)} T), is repeated eight times, the length of the guard interval of the one OFDM symbol period (T _'SYM) (TCP) The same pattern can be repeated twice. In addition, by repeating the pattern for one OFDM symbol period T ' _SYM twice, the FB-STF may form the same patterns repeated 20 times in total for two OFDM symbol periods 2T' _SYM . .

In addition, as shown in FIGS. 7 and 8, when the FFT size is 512, the FB-STF is formed such that the same pattern is repeated 20 times during one OFDM symbol period T ' _SYM in the time domain. Can be designed.

That is, in the FB-STF, the same pattern is repeated 16 times during the effective OFDM symbol period T ' _{eff_SYM} , and the same pattern is repeated 4 times during the guard period TCP, thereby _causing one OFDM symbol period (T' _SYM ). The same pattern may be repeated 20 times in total.

As such, when the FFT size is increased from 256 to 512, even when the FB-STF is transmitted in only one OFDM symbol, when the FB-STF is transmitted in two OFDM symbols (that is, the FFT size is 256). It may have the same frequency acquisition range and the estimation error.

Meanwhile, the above-described example is only an example of an embodiment of the present invention, and the number of times the same pattern is repeated during the effective OFDM symbol period T ' _{eff_SYM} and the pattern of the OFDM symbol period T' _SYM are repeated. The number of times and the length of the guard interval (cyclic prefix) may be designed differently, but the present invention is not limited thereto.

The number of times the FB-STF repeats the same pattern in the time domain can be designed even if the number of guard subcarriers shown in FIGS. 5 to 8 is different.

That is, in the frequency domain, even if the number of guard subcarriers is changed, N (= integer) times the subcarrier spacing (subcarrier spacing = 1 / effective OFDM symbol period) in the sequence of the FB-STF. A non-zero value may be allocated to a position of a subcarrier and a zero value may be allocated to a position of the remaining subcarriers. Then, the FB-STF may be designed such that the same pattern is repeated N times in the time domain.

For example, referring to FIGS. 5 and 6, since the non-zero value is repeated every 8 times in the sequence of the FB-STF, it can be confirmed that N is 8. Accordingly, the FB-STF having an FFT size of 256 may have a form in which the same pattern is repeated eight times during one effective OFDM symbol period T ′ _{eff_SYM} regardless of the change in the number of guard subcarriers.

7 and 8, it can be seen that N is 16 since a non-zero value is repeated every 16 times in the sequence of the FB-STF. Accordingly, the FB-STF having an FFT size of 512 may have a form in which the same pattern is repeated 16 times during one effective OFDM symbol period T ′ _{eff_SYM} regardless of the change in the number of guard subcarriers.

On the other hand, as shown in Figures 5 to 8, the pattern of the FB-STF may be defined as a Real signal or a Complex signal in the frequency domain. In this case, the real signal may be a case where an OFDM symbol is mapped by a BPSK modulation scheme, and the case where the OFDM symbol is defined by a complex signal may be a case where the OFDM symbols are mapped by a QPSK modulation scheme. In addition, in the above-described embodiment, the case in which the FFT size is 256 or 512 has been described as an example. However, the same principle may be applied to the FB-STF for the FFT size different from the FFT size.

9 and 10 are diagrams illustrating an FB-LTF pattern in a frequency domain according to an embodiment of the present invention. 9 shows an FB-LTF pattern when the FFT size is 256, and FIG. 10 shows an FB-LTF pattern when the FFT size is 512. FIG.

Referring to FIG. 9, when the FFT size is 256, the FB-LTF pattern includes a total of 256 subcarriers in the frequency domain. The total number of subcarriers constituting the FB-LTF pattern is equal to the sum of the number of effective subcarriers and the number of null tones. For example, the FB-LTF pattern shown in FIG. 9 may be configured with a total of 256 subcarriers including 234 effective subcarriers and 22 null tones.

Referring to FIG. 10, when the FFT size is 512, the FB-LTF pattern includes a total of 512 subcarriers in the frequency domain. The total number of subcarriers constituting the FB-LTF pattern is equal to the sum of the number of effective subcarriers and the number of null tones. For example, the FB-LTF pattern illustrated in FIG. 10 may include a total of 512 subcarriers including 492 effective subcarriers and 20 null tones.

The FB-LTF is configured to receive the channel at the receiving end to enable channel estimation and to provide a low peak-to-average power ratio (PAPR) characteristic.

The FB-LTF may be converted into a time domain signal from the frequency domain signal of FIGS. 9 and 10 through an inverse fast Fourier transform (hereinafter referred to as IFFT). In this case, the FB-LTF may be transmitted by repeating the signal of the effective OFDM symbol period (T ' _{eff_SYM} ) J times and configuring the length of the entire guard interval to be K times the effective OFDM symbol period (T' _{eff_SYM} ). have.

For example, FB-LTF ₁ of the FB dedicated format frame 420 of FIG. 4 is composed of J = 2 and K = 1/2, and the length thereof is twice the length of one OFDM symbol period (2T ' _SYM ). Can be. In addition, FB-LTF ₁ of the FB mixed format frame 430 of FIG. 4 may be configured such that J = 1 and K = 1/4, and the length thereof is one OFDM symbol period T ′ _SYM . .

On the other hand, the above-described example is only an example of an embodiment of the present invention, the J and K may have different values, but is not limited thereto. In addition, the above-described example is limited to the case where the FFT size is 256 or 512. However, the same principle may be applied to the FB-LTF even for the FFT size different from the FFT size.

The FB-SIG field and the FB-DATA field according to an embodiment of the present invention may be configured in a manner similar to the SIG field and the DATA field of the existing legacy format frame. However, unlike the SIG field and the DATA field, the FB-SIG field and the FB-DATA field may be configured using the operating bandwidth (B MHz) of the TVWS, not the operating bandwidth (A MHz) of the WLAN system.

11 is a schematic block diagram of a wireless LAN device according to an embodiment of the present invention. In this case, the WLAN device includes an access point and / or stations forming a wireless network.

Referring to FIG. 11, the WLAN apparatus 1100 includes an RF front end 1110, a PHY unit 1120, a MAC unit 1130, and a controller 1140.

The RF front end 1110 converts a signal output from the PHY unit 1120, which is a physical layer, into a radio frequency (hereinafter referred to as RF) signal, and then filters and / or amplifies the signal. It transmits through a transmission antenna.

In addition, the RF front end 1110 converts the RF signal input through the reception antenna into a digital signal that can be processed by the PHY unit 1120 through a process such as filtering and outputs the digital signal. The RF front end 1110 may further include an RF switch function for switching a transmission operation and a reception operation of the WLAN apparatus 1100.

The PHY unit 1120 encodes forward error correction (FEC) for data requested to be transmitted from the MAC unit 1130 which is a medium access control layer. And perform a process such as performing modulation and adding signals such as preamble and pilot to the RF front end 1110.

In addition, the PHY unit 1120 performs demodulation, equalization, and FEC decoding on the received signal input through the RF front end 1110, and a preamble added by the transmitter. And performing a process such as removing a pilot signal and delivering it to the MAC unit 1130. In order to perform such an operation, the PHY unit 210 may include a modulator, a demodulator, an equalizer, an FEC encoder, a FEC decoder, and the like. Can be.

The MAC unit 1130 processes the data transmitted from the upper layer, provides the PHY unit 1120, and is responsible for additional transmission and reception for data transmission. In addition, the MAC unit 1130 processes the received data input from the PHY unit 1120 and transfers it to a higher layer, and is responsible for additional transmission and reception necessary for the data transfer.

The controller 1140 effectively controls the operations of the RF front end 1110, the PHY unit 1120, and the MAC unit 1130 based on a control signal transmitted from an upper layer, thereby requesting an operation from the upper layer. This can be done smoothly.

In addition, the controller 1140 may control an overall operation for performing a method of transmitting / receiving a wireless LAN apparatus according to an embodiment of the present invention.

12 is a block diagram of a transmitter for transmitting a data signal (or frame) in an existing WLAN system.

Referring to FIG. 12, the transmitter 1200 includes a scrambler 1201, an FEC encoder 1203, an interleaver 1205, a mapper 1207, an inverse fast Fourier transform unit IFFT, 1209), CP inserter 1211, preamble and signal field inserter 1213, multiplexer 1215, pulse shaping unit 1217, digital to analog converter (DAC) 1219, an up-converter 1221, a power amplifier 1223, and an antenna 1225. In addition, the transmitting device 1200 may further include a serial / parallel converter (not shown) between the interleaver 1205 and the mapper 1207.

The scrambler 1201 plays a role of uniformly distributing a corresponding signal in the frequency domain by allowing a data bit stream transmitted from an upper layer to have a random sequence characteristic.

The FEC encoder 1203 encodes the data bits scrambled by the scrambler 1201 according to a predetermined encoding method and outputs the encoded data bits. The FEC encoder 1203 may be implemented as a convolutional encoder, a turbo encoder, a low density parity check encoder, or the like as an error correction code.

The interleaver 1205 interleaves the encoded data bits to prevent burst errors. The serial / parallel converter (not shown) converts a serial signal output from the interleaver 1205 into a parallel signal.

The mapper 1207 modulates the parallel signal output from the serial / parallel converter according to a predetermined modulation method and outputs modulation symbols. In other words, the encoded data bits are mapped by the mapper 1207 to modulation symbols representing positions according to amplitude and phase constellation. The modulation scheme (modulatin scheme) in the mapper 1207 is not limited, and m-Phase Shift Keying (m-PSK) or m-Quardrature Amplitude Modulation (m-QAM) may be used.

The IFFT unit 1209 performs inverse fast Fourier transform on the modulation symbols output from the mapper 1207 and converts them into OFDM symbols in a time domain.

The CP inserter 1217 adds a cyclic prefix CP, which is a guard interval, to OFDM symbols in the time domain. The cyclic prefix converts a frequency selective channel into a flat fading channel by removing inter-symbol interference (ISI).

The preamble and signal field inserter 1213 adds a preamble and a signal field before the OFDM symbols into which the CP is inserted. Here, the preamble is used for time synchronization, frequency synchronization, channel estimation, and the like at the receiving end, and the signal field is used to provide control information about a coding rate, modulation scheme, packet length, and the like.

The multiplexer 1215 multiplexes signals output from the CP inserter and signals output from the preamble and signal field inserter 1213 into one OFMD symbol.

The pulse shaping unit 1217 adjusts frequency characteristics of the signal output from the multiplexer 1215 using a predetermined pulse shaping method. The pulse shaping method used by the pulse shaping unit 1217 includes a general time domain filtering method and a time domain windowing method for smoothing the transition between OFDM symbols. There is this. The pulse shaping unit 1217 may use any one of the time domain windowing method and the time domain filtering method, or both of the above methods.

The DAC 1219 converts a transmission frame output from the pulse shaping unit 1217 into an analog signal. The up converter 1221 adjusts the analog signal output from the DAC 1219 to a frequency band signal to be transmitted to the power amplifier 1223. Then, the power amplifier 1223 amplifies the analog signal output from the up converter 1221 and transmits it through the antenna 1225.

FIG. 13 is a block diagram of a transmitter for generating a control signal in an existing WLAN system. Here, the control signal includes a preamble (STF, LTF) and a signal field (Signal Field). The process of generating the control signal is similar to the process of generating the data signal shown in FIG. 12, and may share a portion used to generate the data signal.

Referring to FIG. 13, the transmitter 1300 includes an FEC encoder 1301, an interleaver 1303, a mapper 1305, an inverse fast Fourier transform unit IFFT 1307, and a CP insertion unit 1. 1309). In addition, the transmitting device 1300 may further include a serial / parallel converter (not shown) between the interleaver 1303 and the mapper 1305.

The FEC encoder 1301 encodes a signal bit stream transmitted from an upper layer according to a predetermined encoding method and outputs encoded signal bits. Thereafter, the interleaver 1303 serves to prevent burst error by interleaving the encoded signal bits. The serial / parallel converter (not shown) converts a serial signal output from the interleaver 1303 into a parallel signal.

The mapper 1305 modulates the parallel signal converted by the serial / parallel converter according to a predetermined modulation method and outputs modulation symbols. That is, the coded signal bits are mapped by the mapper 1305 to modulation symbols representing positions according to amplitude and phase constellation. The modulation scheme (modulatin scheme) in the mapper 1305 is not limited, and m-Phase Shift Keying (m-PSK) or m-Quardrature Amplitude Modulation (m-QAM) may be used.

For example, the mapper 1305 may generate preambles STF and LTF as shown in FIGS. 5 to 10. That is, when the STF and the LTF are defined as Real signals, the mapper 1305 assigns -1, 0, and 1 values to the plurality of subcarriers using the BPSK scheme.

On the other hand, when the STF and LTF are defined as a complex signal, the mapper 1305 assigns-(1 + j), 0, (1 + j) values to the plurality of subcarriers using the QPSK scheme. At this time, the mapper 1305 assigns values to subcarriers in a predetermined manner according to the type of the preamble.

The IFFT unit 1307 performs inverse fast Fourier transform on the modulation symbols output from the mapper 1305 and converts them into OFDM symbols in the time domain. The CP inserter 1309 generates a control signal by adding a cyclic prefix, which is a guard interval, to the OFDM symbols of the time domain. Such a control signal may be added to the data field through the preamble and signal field inserter 1213 of FIG. 12 to form a transmission frame.

Meanwhile, the controller (not shown) may generate and transmit a frame including a data field, a preamble, and a signal field by controlling the components of FIGS. 12 and 13 as a whole based on a command transmitted from an upper layer.

14 is a diagram illustrating an example of a transmitting device for transmitting a frame in an FB WLAN system.

Referring to FIG. 14, the transmission device 1400 may include a legacy format frame generator 1410, an FB format frame generator 1450, a switch unit 1437, a DAC 1439, Up converter 1441, power amplifier 1443, and antenna 1445.

More specifically, the transmitting device 1400 generates a legacy format frame generator 1410 for generating the legacy format frame 410 and an FB format frame generator 1450 for generating the FB format frames 420 and 430. It may include. The legacy format frame generator 1410 and the FB format frame generator may include the same components as those of the transmitting apparatus illustrated in FIG. 12.

That is, each of the legacy format frame generator 1410 and the FB format frame generator 1450 is a scrambler 1401, 1419, FEC encoders 1403, 1421, interleavers 1405, 1423, mapper 1407, 1425, Inverse fast Fourier transforms 1409 and 1427, CP inserters 1411 and 1429, preamble and signal field inserters 1413 and 1431, multiplexers 1415 and 1433 and pulse shaping parts 1417 and 1435. can do.

However, the detailed operation method or parameters for the operation of each component may be set differently from the legacy format frame and the FB format frame. For example, FEC encoders of other coding schemes may be used, sizes of IFFT blocks may be different, and there may be differences in modulation schemes supported by the mapper. In addition, an operating clock used to generate the legacy format frame and the FB format frame may be different.

For example, assuming that the channel bandwidth of the TVWS available in the FB WLAN system is B (MHz) and that the channel bandwidth used in the existing WLAN system is A (MHz), the legacy format frame operates at A (MHz). The clock may be generated, and the FB format frame may be generated by an operation clock of B (MHz). On the other hand, this is an example of embodiment of the present invention, the generation of the legacy format frame and the FB format frame may be any frequency clock different from the operation clock.

The legacy format frame generator 1410 may generate a legacy format frame by processing a data bit stream of a legacy format transferred from an upper layer. Here, the process of generating the legacy format frame is the same as the process of generating the transport frame of FIG. 12.

Meanwhile, the FB format frame generator 1450 may generate an FB format frame by processing a data bit stream of the FB format delivered from an upper layer.

The switch unit 1437 plays a role of generating an FB mixed format frame 430 by switching from a legacy format frame to an FB format frame. As shown in FIG. 4, the FB mixed format frame 430 is a structure in which a legacy format frame 415 of A MHz and an FB format frame 425 of B MHz are combined.

That is, when the legacy format frame 415 of A MHz is generated by the legacy format frame generator 1410, the switch unit 1437 switches the frame generation path so that the B MHz format is generated by the FB format frame generator 1450. FB format frame 425 is generated. However, when only the legacy format frame 410 or the FB dedicated format frame 420 is generated by the transmitting device 1400, the switch unit 1435 simply bypasses the switch unit 1437.

The DAC 1439 converts three types of frames output from the switch unit 1437 into analog signals. The up-converter 1441 adjusts the analog signal output from the DAC 1439 up to a frequency band signal to be transmitted and outputs it to the power amplifier 1443. Then, the power amplifier 1443 amplifies the analog signal output from the up-converter 1441 and transmits it through the antenna 1445.

On the other hand, the controller (not shown) controls the overall operation of the transmitting device 1400 based on the command transmitted from the upper layer to the legacy format frame 410, FB dedicated format frame 420 or FB mixed format frame 430 ) Can generate any one frame.

15 is a diagram illustrating another example of a transmitter for transmitting a frame in an FB WLAN system. Unlike the transmitting apparatus of FIG. 14 described above, the transmitting apparatus 1500 uses a single format frame generator 1550 to perform a legacy format frame 410, an FB dedicated format frame 420, and an FB mixed format frame 430. Any one of frames may be generated. That is, the transmitter 1500 may share one format frame generator 1550, thereby reducing the complexity of hardware required to implement the transmitter.

Referring to FIG. 15, the transmission apparatus 1500 may include a frame format generator 1550, a conversion controller 1519, a DAC 1521, an up converter 1523, a power amplifier 1525, and an antenna 1527. ).

The format frame generator 1550 includes a scrambler 1501, an FEC encoder 1503, an interleaver 1505, a mapper 1507, an inverse fast Fourier transform unit 1509, a CP inserter 1511, a preamble, and a signal field. The inserter 1513, the multiplexer 1515, and the pulse molding unit 1517 may be included.

The format frame generator 1550 may generate a legacy format frame 410 or an FB format frame 420 or 430 by processing a legacy data bit stream or an FB format data bit stream transmitted from an upper layer. Herein, the format frame generator 1550 may adjust its operation clock according to which type of frame among three types of frames.

In this case, the conversion control unit 1519 operates only when the format frame generator 1550 generates the FB mixed format frame 430. That is, when the format frame generator 1550 generates the legacy format frame 410 or the FB dedicated format frame 420, the format control unit 1519 simply bypasses the conversion controller 1519.

Meanwhile, when the FB mixed format frame 430 is to be transmitted, the conversion controller 1519 stores a preamble and a signal field of a legacy format frame generated by the format frame generator 1550 in memory (not shown). Save it temporarily. The conversion control unit 1519 performs an operation of aligning timing to combine the FB format frame generated by the format frame generator 1550 with the preamble and signal fields stored in the memory. In this case, the timing alignment may be performed by the conversion controller 1519 controlling the preamble and the signal field insertion unit 1513.

The DAC 1521 converts a frame output from the conversion controller 1519 into an analog signal. The up converter 1523 adjusts the analog signal output from the DAC 1521 up to a frequency band signal to be transmitted to the power amplifier 1525. Then, the power amplifier 1525 amplifies the analog signal output from the up converter 1523 and transmits it through the antenna 1525.

Meanwhile, the controller (not shown) controls the overall operation of the transmitter 1500 based on a command transmitted from an upper layer to control the legacy format frame 410, the FB dedicated format frame 420, and the FB mixed format frame 430. Any one of frames may be generated.

FIG. 16 is a diagram illustrating a procedure of transmitting a frame by the transmitting apparatus of FIG. 15.

Referring to FIG. 16, when a control signal for requesting frame transmission is received from an upper layer, the controller determines whether a frame should be transmitted by the transmitting apparatus 1500. Subsequently, when a type of a frame to be transmitted is determined by the transmitting device 1500, the controller controls an operation for generating the determined frame by the transmitting device 1500.

First, in step 1601, the controller determines whether the type of the frame is a legacy format frame.

As a result of the check, if the frame is a legacy format frame, the flow proceeds to step 1603. In operation 1603, the format frame generator 1550 generates a legacy format frame 410 by operating with a clock of A (MHz).

In contrast, if the frame is not a legacy format frame, the flow proceeds to step 1611. In operation 1611, the controller determines whether the type of the frame is an FB dedicated format frame 420.

As a result of the check, if the frame is an FB dedicated format frame 420, the flow proceeds to step 1613. In operation 1613, the format frame generator 1550 operates with a clock of B (MHz) to generate an FB dedicated format frame 420.

When the generation of the legacy format frame 410 or the FB dedicated format frame 420 is completed in steps 1603 and 1613, the process proceeds to the next step, step 1605, and simply bypasses the conversion control unit 1519. . In operation 1607, the legacy format frame 410 or the FB dedicated format frame 420 is converted into an analog signal. In operation 1609, the frame converted into the analog signal is transmitted through an antenna.

On the other hand, if the frame is not the FB format frame 420, go to step 1615. In step 1615, the controller determines whether the type of the frame is an FB mixed format frame.

As a result of the check, if the frame is an FB mixed format frame, the process proceeds to step 1617;

In step 1617, the format frame generator 1550 operates with a clock of A MHz to generate the preamble and signal field 415 of the legacy format frame. In operation 1619, the preamble and signal field 415 is temporarily stored in the memory. In operation 1621, the format frame generator 1550 operates with a clock of B MHz to generate a preamble, a signal field, and a data field of the FB format frame 425.

In operation 1623, the conversion control unit 1519 performs timing alignment to combine the preamble and signal fields 415 stored in the memory with the FB format frame 425 generated by the format frame generator 1550. . As a result, the conversion control unit 1519 may generate the FB mixed format frame 430 in which the legacy format frame 415 and the FB format frame 425 are combined.

When the step 1623 is completed, in step 1607 and 1609, the transmitting device 1500 performs an analog signal processing on the FB mixed format frame 430 and transmits through the antenna.

17 is a diagram illustrating an example of a reception device for receiving a frame in an FB WLAN system.

Referring to FIG. 17, the reception device 1700 includes an RF front end 1701, an analog-to-digital converter (hereinafter, referred to as an 'ADC', 1703), and an auto gain controller. , 1705, low pass filter, 1707, IQMC (Inphase Quadrature Mismatch Compensation) unit 1709, legacy format bit generator 1710, and the like. An FB format bit generator 1750 is included.

The receiving device 1700 includes a legacy format bit generator 1710 for outputting a legacy bit stream and a FB format bit generator 1750 for outputting a bit stream in FB format.

In addition, the legacy format bit generator 1710 and the FB format bit generator 1750 are resamplers 1711 and 1725, frequency correction units 1713 and 1727, and matched filters. Filter, 1715, 1729, down sampler (1/2 Decimation, 1717, 1731), CP remover (1719, 1733), Fast Fourier Transform (1721, 1735), preamble detector (1723, 1737), de-mapper (not shown), parallel to serial converter (not shown), deinterleaver (not shown), FEC decoder (decoder, not shown) and descrambler (De-scrambler, not shown).

Meanwhile, although the legacy format bit generator 1710 and the FB format bit generator 1750 include the same components, detailed operation schemes or parameters for operating the components may be set differently. For example, FEC decoders of different decoding schemes may be used, sizes of FFT blocks may be different, and there may be differences in demodulation schemes supported by the demapper. In addition, the frequencies of the clocks operating in the legacy format bit generator 1710 and the FB format bit generator 1750 may be set differently.

First, the RF front end 1701 adjusts a power gain of an RF signal received through an antenna, and converts the RF signal into an intermediate frequency signal. At this time, the power gain adjustment by the RF front end 1701 may be made by itself or through the AGC 1705.

The ADC 1703 converts the analog signal passing through the RF front end 1701 into a digital signal. The low pass filter 1707 removes phase noise and noise by filtering the digital signal output from the ADC 1703. Next, the IQMC unit 1709 compensates for orthogonal imbalance occurring in the OFDM reception signal passing through the low pass filter 1707.

The signal output from the IQMC unit 1709 is input to the legacy format bit generator 1710 or the FB format bit generator 1750 according to the type of the received frame. That is, when the received frame is a legacy format frame 410, the signal output from the IQMC unit 1709 is input to the legacy format bit generator 1710. On the other hand, when the received frame is an FB format frame 420 or 430, the signal output from the IQMC unit 1709 is input to the FB format bit generator 1750.

The resamplers 1711 and 1725 convert the signal output from the IQMC unit 1709 into an oversampled signal by an integer multiple of the sampling frequency of the OFDM symbol. At this time, since the receiving device 1700 must be able to receive both the data bit of the legacy format and the data bit of the FB format, it must be able to resample the received signal to two sampling frequencies.

For example, the resampler 1711 of the legacy format bit generator 1710 may resample an OFDM received signal to a sampling frequency of 10 MHz, and the resampler 1725 of the FB format bit generator 1750 may resample the OFDM signal. The received signal can be resampled at a sampling frequency of 12 MHz. Meanwhile, the sampling frequencies of 10 MHz and 12 MHz represent an example of a sampling frequency used when the channel bandwidth of the TVWS is 6 MHz and the channel bandwidth of the existing WLAN system is 5 MHz, and the channel bandwidth of the TVWS and the existing WLAN system. It may have any other value according to the channel bandwidth of.

The frequency correctors 1713 and 1727 compensate for the frequency offset values estimated by the preamble detectors 1723 and 1737 to obtain frequency synchronization of the received signal. Thereafter, the signals output from the frequency correctors 1713 and 1727 pass through the matched filters 1715 and 1729 in order to maximize the signal to noise ratio (SNR).

The down samplers 1725 and 1731 downsample the signals output from the matched filters 1715 and 1729 to the sampling frequency of the OFDM symbol. For example, half-decimation of the oversampled sampling frequencies of 10 MHz and 12 MHz is performed to downsample the sampling frequencies of 5 MHz and 6 MHz.

The CP removers 1725 and 1733 remove the cyclic prefix of the signal passing through the down samplers 1725 and 1731. In this case, the CP removers 1725 and 1733 may accurately remove the cyclic prefix by using the timing estimated by the preamble detectors 1723 and 1737. The OFDM symbol from which the CP is removed is then fast Fourier transformed by the FFT units 1721 and 1735 to be transformed into frequency domain OFDM symbols.

The demapper (not shown) is controlled by a demodulation signal of a controller (not shown) to demap the OFDM symbol into coded data bits. Here, the demodulation scheme provided by the controller corresponds to a modulation scheme performed by the mapper of the transmitting apparatus illustrated in FIGS. 14 and 15.

The parallel / serial converter converts the parallel signal output from the demapper into a serial signal and outputs the serial signal to a deinterleaver (not shown). The deinterleaver performs deinterleaving on the signal output from the parallel / serial converter based on the interleaving pattern used at the transmitter.

The FEC decoder (not shown) is controlled by the control unit to decode the deinterleaved data. Here, the decoding scheme provided by the controller corresponds to an encoding scheme performed by the FEC encoder of the transmitting apparatus shown in FIGS. 14 and 15.

The descrambler (not shown) descrambles the decoded signal passing through the FEC decoder to output a bit stream of a legacy format or a bit stream of an FB format.

The controller (not shown) may control the overall operation of the receiving apparatus 1700 to output a bit stream of a legacy format or a bit stream of an FB format. For example, the controller detects the STF of the received frame to determine the type of the received frame. The controller may control the components of the receiving apparatus 1700 such that the bit stream of the legacy format or the bit stream of the FB format is output according to the type of the frame.

18 is a diagram illustrating a procedure of receiving a frame by the receiving device of FIG. 17.

Referring to FIG. 18, in step 1801, the receiving device 1700 receives a frame through an antenna. Next, in step 1803, the controller determines whether the strength of the signal received through the antenna is greater than a reference level (or threshold).

As a result of the check, when the strength of the received signal is greater than the reference level, the flow proceeds to step 1805. In step 1805, the controller adjusts the strength of the received signal by a predetermined value using AGC, and then moves to step 1807. On the other hand, if the intensity of the received signal is less than the reference level, go directly to step 1807 without going through the AGC.

In step 1807, the controller determines whether the legacy format bit generator 1710 detects the STF of the legacy format frame.

As a result of the check, if the STF of the legacy format frame is detected, the process proceeds to step 1811 to determine whether the STF of the FB format frame is detected.

If it is determined in step 1811 that the STF of the FB format frame is not detected, go to step 1813. In operation 1813, the reception apparatus 1700 performs a signal processing process for receiving the legacy format frame 410.

On the other hand, if it is determined in step 1811 that the STF of the FB format frame is detected, go to step 1815. In operation 1815, the receiving apparatus 1700 performs a signal processing process for receiving the FB mixed format frame 430.

In step 1807, if the STF of the legacy format frame is not detected, go to step 1809, and then check whether the STF of the FB format frame is detected. If it is determined in step 1809 that the STF of the FB format frame is not detected, the process moves back to step 1807.

On the other hand, if it is determined in step 1809 that the STF of the FB format frame is detected, go to step 1817. In operation 1817, the reception apparatus 1700 performs a signal processing process for receiving the FB dedicated format frame 420.

19 is a block diagram of a receiving apparatus including a frequency tracking loop for channel compensation in an FB WLAN system according to an embodiment of the present invention. Here, the frequency tracking loop includes a carrier frequency tracking loop and a sampling frequency tracking loop.

The reception device 1900 may further include a phase error estimator 1920 and a time error estimator 1930 in the reception device of FIG. 17. The phase error estimator 1920 and the time error estimator 1930 may be applied to the legacy format bit generator 1710 and the FB format bit generator 1750 illustrated in FIG. 17, respectively.

The phase error estimator 1920 includes a phase error detection unit 1915, a loop filter 1917, and a numerically controlled oscillator 1919.

The phase error detector 1915 receives a signal output from the FFT unit 1911 to detect a phase error, and the loop filter 1917 accumulates the detected phase error.

The numerically controlled oscillator 1919 estimates a phase error based on the accumulated phase error, and provides the estimated phase error to the frequency corrector 1901. Then, the frequency corrector 1903 compensates for the phase error by adjusting the carrier frequency based on the estimated phase error.

The time error estimator 1930 includes a timing error detection unit 1921, a loop filter 1923, and a timing controller 1925.

The time error detector 1921 receives a signal output from the FFT unit 1911 to detect a time error, and the loop filter 1923 accumulates the detected time error.

The timing controller 1925 estimates a time error based on the accumulated time error, and provides the estimated time error to the resampler 1901. The resampler 1901 then compensates for the time error by adjusting the sampling frequency based on the estimated time error.

20 shows another example of a receiving apparatus for receiving a frame in an FB WLAN system according to an embodiment of the present invention. Unlike the reception device of FIG. 17 described above, the reception device 2000 may reduce the complexity of hardware required to implement the reception end by sharing the FFT unit and subsequent processing devices thereafter. Meanwhile, in the description of the components of the receiving apparatus 2000, the content overlapping with the components of FIG. 17 described above will be omitted, and the differences will be mainly described.

Referring to FIG. 20, the receiving device 2000 includes an RF front end (not shown), an analog-to-digital converter (not shown), an automatic gain controller (AGC, not shown), and a low pass filter (LPF, not shown). , IQMC unit (not shown), legacy format bit generator 2010 and FB format bit generator 2050, multiplexer 2023, FFT unit 2025, de-mapper (not shown), bottle / A parallel to serial converter (not shown), a de-interleaver (not shown), an FEC decoder (not shown), and a descrambler (not shown) are included.

The receiving device 2000 includes a legacy format bit generator 2010 for outputting a legacy bit stream and a FB format bit generator 2050 for outputting an FB format bit stream.

In addition, the legacy format bit generator 2010 and the FB format bit generator 2050 may each be a re-sampler (Resampler, 2001, 2011), a frequency correction unit (Frequency Correction Unit, 2003, 2013), a matched filter (Matched). Filter, 2005, 2015), down sampler (1/2 Decimation, 2007, 2017), CP remover (2009, 2019) and preamble detector (2008, 2021).

Meanwhile, although the legacy format bit generator 2010 and the FB format bit generator 2050 include the same components, detailed operation schemes or parameters for operating the components may be set differently. For example, different decoding FEC decoders may be used, and there may be differences in demodulation schemes supported by the demapper. In addition, the frequencies of the clocks operating in the legacy format bit generator 2010 and the FB format bit generator 2050 may be set differently.

The overall operation of the receiving apparatus 2000 will be briefly described as follows.

The signal received through the antenna of the receiving device 2000 is input to the legacy format bit generator 2010 or the FB format bit generator 2050 according to the type of the received frame. That is, when the received frame is a legacy format frame 410, a signal output from an IQMC unit (not shown) is input to the legacy format bit generator 2010. On the other hand, when the received frame is an FB format frame 420 or 430, a signal output from the IQMC unit (not shown) is input to the FB format bit generator 2050.

The legacy format bit generator 2010 or the FB format bit generator 2050 performs signal processing for generating a bit stream of a legacy format or a bit stream of an FB format, and the signal processed signal is the multiplexer 2023. Is provided.

The multiplexer 2023 multiplexes the signal output from the legacy format bit generator 2010 or the FB format bit generator 2050 to the FFT unit 2025. At this time, the multiplexer 2023 multiplexes using the timing estimated by the preamble detectors 2008 and 2021.

Then, the signal output from the multiplexer 2023 is the FFT unit 2025, demapper (not shown), bottle / serial converter (not shown), deinterleaver (not shown), FEC decoder (not shown) and de The scrambler (not shown) outputs the bit stream in legacy or FB format.

The controller (not shown) may control the overall operation of the receiving apparatus 2000 such that the bit stream of the legacy format or the bit stream of the FB format is output. For example, the controller determines the type of the received frame by detecting the STF of the received frame. The controller may select a signal processing path according to the determined frame type, and select an operating clock frequency and an FFT size of the FFT unit 2025.

21 illustrates another example of a receiving apparatus for receiving a frame in an FB WLAN system according to an embodiment of the present invention. Unlike the reception apparatus of FIG. 17 described above, the reception apparatus 2100 uses two signal processing paths required for signal processing in a legacy format and an FB format as one signal processing path, thereby implementing hardware necessary for implementing a receiver. Can reduce the complexity. Meanwhile, in the description of the components of the reception device 2100, the content overlapping with the components of FIG. 17 will be omitted, and the differences will be described.

Referring to FIG. 21, the receiving device 2100 includes an RF front end (not shown), an analog-to-digital converter (not shown), an automatic gain controller (AGC, not shown), a low pass filter (LPF, not shown). , IQMC unit (not shown), first resampler 2101, second resampler 2105, memory 2103, multiplexer 2107, frequency corrector 2109, matched filter 2111, down sampler ( 2113, CP remover 2115, FFT unit 2117, preamble detector 2119, control unit 2121, de-mapper (not shown), parallel to serial converter (not shown) C), a de-interleaver (not shown), an FEC decoder (not shown), and a descrambler (not shown).

That is, the receiving device 2100 may further include the memory 2103 after the first resampler 2101 instead of reducing two signal processing paths into one signal processing path.

The overall operation of the receiving device 2100 will be described briefly as follows.

Signals received through the antenna of the reception device 2100 are respectively input to the first resampler 2101 or the second resampler 2105 according to the type of the received frame. That is, when the received frame is a legacy format frame 410, the signal output from the IQMC unit (not shown) is input to the second resampler 2105. On the other hand, if the received frame is an FB format frame 420 or 430, the signal output from the IQMC unit (not shown) is input to the first resampler 2101.

The first resampler 2101 or the second resampler 2105 resamples a signal output from the IQMC unit (not shown), and the resampled signal is provided to the multiplexer 2107. In addition, the signal output from the first resampler 2101 may be stored in the memory 2103 in a first input first ouput (FIFO) format.

The multiplexer 2107 multiplexes a signal output from the first resampler 2101 or the second resampler 2105 based on a control command of the controller 2121. In this case, the controller 2121 may control the multiplexer 2107 by using the timing value estimated by the preamble detector 2119.

Thereafter, the signal output from the multiplexer 2107 is the frequency corrector 2109, the matched filter 2111, the down sampler 2113, the CP remover 2115, the FFT unit 2117, and a demapper (not shown). ), A bottle / serial converter (not shown), a deinterleaver (not shown), an FEC decoder (not shown), and a descrambler (not shown), and output as a bit stream in a legacy format or an FB format.

The controller 2121 may control the overall operation of the receiving device 2100 such that the bit stream of the legacy format or the bit stream of the FB format is output. For example, the controller 2121 determines the type of the received frame by detecting the STF of the received frame. The controller 2121 may control signal processing for a legacy format or an FB format according to the type of the determined frame.

FIG. 22 is a diagram illustrating a procedure of receiving a frame by the receiving device of FIG. 21.

Referring to FIG. 22, in step 2201, the receiving device 2100 receives a frame through an antenna.

In step 2203, the controller 2121 determines whether the intensity of the signal received through the antenna is greater than a reference level (or threshold).

As a result of the checking, when the strength of the received signal is greater than the reference level, the control proceeds to step 2205. In step 2205, the control unit 2121 adjusts the strength of the received signal by a predetermined value using AGC, and then moves to step 2207. On the other hand, if the intensity of the received signal is less than the reference level, go directly to step 2207 without passing through the AGC.

In step 2207, the memory 2103 stores the signal output from the first resampler 2101 in a FIFO method.

Next, in step 2209, the controller 2121 determines whether the STF of the legacy format frame is detected in the received frame.

As a result of the check, if the STF of the legacy format frame is detected, the flow proceeds to step 2211 to determine whether the STF of the FB format frame is detected.

If it is determined in step 2211 that the STF of the FB format frame is not detected, the process moves to step 2213. In operation 2213, the receiving device 2100 performs a signal processing process for receiving the legacy format frame 410.

On the other hand, if it is determined in step 2211 that the STF of the FB format frame is detected, the process moves to step 2215. In operation 2215, the receiving device 2100 performs a signal processing process for receiving the FB mixed format frame 430.

In step 2209, if the STF of the legacy format frame is not detected, the process moves to step 2217. In operation 2217, the controller 2121 outputs a signal stored in the memory 2103.

Thereafter, in step 2219, the controller 2121 determines whether the STF of the FB format frame is detected with respect to the signal output from the memory 2103.

If the STF of the FB format frame is not detected, the process returns to step 2209 again. However, if the STF of the FB format frame is detected, the process moves to step 2221. In operation 2221, the receiving device 2100 performs a signal processing process for receiving the FB dedicated format frame 420.

As described above, the FB WLAN system according to an embodiment of the present invention may define a new transmission format frame and improve transmission efficiency based on the defined transmission format frame. In addition, the FB WLAN system is compatible with the existing WLAN system, and can effectively transmit and receive data by using different TV frequency bands for different countries.

On the other hand, IEEE 802.11af is in process of standardizing the operation of the wireless LAN system defined in IEEE 802.11 to operate in the TVWS band. According to the IEEE 802.11af, the WLAN system operating in the TVWS band defines the IEEE 802.11 operation for 5MHz, 10MHz, 20MHz, 40MHz channels.

That is, the WLAN system performs communication using any one of the channel bandwidths of the 5MHz, 10MHz, 20MHz, 40MHz channels. At this time, the wireless LAN system needs to define a channel in order to effectively use the TVWS channel bandwidth different for each region.

For example, FIG. 3 illustrates two methods of defining 5 MHz, 10 MHz, 20 MHz, and 40 MHz channels of a WLAN system in a TV white space band in which channels are allocated in units of 6 MHz.

Referring to (a) of FIG. 3, the first channel definition method (Channelization A) for each channel (5/10/20 / 40MHz) of the wireless LAN system, the center frequency (center frequency) of each channel TV channel ( 6MHz) to be located at the center frequency.

Referring to (b) of FIG. 3, a second channel definition method (Channelization B) is performed to continuously generate a center frequency of each channel for each channel (5/10/20 / 40MHz) of the WLAN system. It is located at the boundary of two TV channel bands.

A wireless LAN system using the TVWS band may perform communication using any one of the two channel definition methods. At this time, considering the practical use availability of the TVWS, it is expected that the WLAN system mainly performs communication using a 5MHz channel.

Meanwhile, IEEE 802.11n is a MIMO WLAN system for transmitting high speed data while maintaining compatibility with existing WLAN systems. That is, the IEEE 802.11n defines a High Throughput (HT) operation that provides a higher data rate than IEEE 802.11a / g using a channel bandwidth of 20 MHz or 40 MHz. However, the IEEE 802.11n does not define the operation for the 5MHz and 10MHz channels that are expected to be frequently used in the TVWS band, so it is necessary to define them.

In order to solve this demand, another embodiment of the present invention provides a method for applying a high throughput (HT) operation of IEEE 802.11n to the 5MHz, 10MHz channel in a wireless LAN system operating in the TVWS band.

Hereinafter, another embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 23 is a diagram illustrating a relationship between a MAC layer and a physical layer of the WLAN apparatus illustrated in FIG. 11.

Referring to FIG. 23, a MAC layer 2320 exchanges data with a higher layer (logical link control layer, LLC layer, not shown) through a MAC Service Access Point (MAC SAP) 2330. Here, the LLC layer is one of two sublayers of the data link layer and is involved in traffic management such as flow control and error control on a physical medium.

Also, the MAC layer 2320 exchanges data with a physical layer 2310 through a PHY Service Access Point (2340). The PHY SAP 2340 may also be referred to as a PHY service interface.

The physical layer 2310 is further divided into two sublayers, which are a physical layer convergence procedure sublayer (PLC) 2312 and a physical medium dependent sublayer (PMD 2314). The PLCP sublayer 2312 and the PMD sublayer 2314 exchange data through a PMD Service Access Point (PMD SAP) 2350.

The PLCP sublayer 2312 is a layer defined to ensure that the MAC layer 2320 has a minimum association with the PMD sublayer 2314.

That is, the PLCP sublayer 2312 may use a service generated in the MAC layer 2320 to a physical layer 2310 or a signal in the physical layer 2310 to match a service in the MAC layer 2320. It plays the role of converting to.

In addition, the PLCP sublayer 2312 is a block for enabling the MAC layer 2320 to operate independently of the physical layer 2310.

The PMD sublayer 2314 is a layer that provides a method for the physical layer 2310 to send and receive signals. That is, the PMD sublayer 2314 provides a means for transmitting and receiving data between two or more stations using the OFDM scheme.

In addition, the PMD sublayer 2314 is closely related to the physical layer 2310, and serves to change a service in an IEEE 802.11 MAC to be suitable for physical layer operation.

The physical layer 2310 further includes a PHY Layer Management Entity (hereinafter referred to as “PLME”, in addition to the two sublayers 2312 and 2314).

The PLME (not shown) manages a function of a physical layer by interworking with a MAC layer management entity (MLME). In addition, the PLME delivers service primitives through the PMD SAP 2350 between the PLCP sublayer 2312 and the PMD sublayer 2314. Here, TXVECTOR 2370, RXVECTOR 2360, and PHYCONFIG_VECTOR (not shown) exist in the service primitives parameters defined in the service primitive.

The physical layer 2310 connects to the MAC layer 2320 through the TXVECTOR 2370, the RXVECTOR 2360, and the PHYCONFIG_VECTOR. That is, the TXVECTOR 2370 provides packet transmission parameters from the MAC layer 2320 to the physical layer 2310. The physical layer 2310 informs the MAC layer 2320 of the received packet parameters by using the RXVECTOR 2360. In addition, the MAC layer 2320 sets the physical layer 2310 using the PHYCONFIG_VECTOR. More specifically, the MAC layer 2320 of the transmitting station is connected to the PLCP sublayer (PHY SAP 2340). Deliver TXVECTOR 2370 to 2312. Then, the PLCP sublayer 2312 and the PMD sublayer 2314 constitute a packet to be transmitted using the TXVECTOR 2370.

The TXVECTOR 2370 includes parameters such as a length LENGTH, a data rate, a service, and a transmit power TX_POWER of the data transmitted through signal modulation in the PHY layer 2310. Here, the length parameter indicates the number of data octets of the signal to be transmitted through the antenna, and the data rate parameter indicates the data rate of the signal to be transmitted. In addition, the service parameter is composed of seven null bits for the initialization of the scrambler and nine null bits reserved, and the transmission power parameter is used to determine the power of the signal to be transmitted.

The service primitive associated with the TXVECTOR 2370 parameter is PHY-TXSTART.request. That is, the TXVECTOR 2370 is used as an argument of the function of PHY-TXSTART.request.

Meanwhile, the PLCP sublayer 2312 of the receiving station delivers the RXVECTOR 2360 to the MAC layer 2320 via the PHY SAP 2340. The MAC layer 2320 then analyzes the received packet using the RXVECTOR 2360.

The RXVECTOR 2360 includes parameters such as a received signal strength indicator (RSSI), a length (LENGTH), and a data rate (DATARATE). Here, the RSSI parameter indicates the strength of the signal received through the antenna. Further, the length parameter indicates the number of data octets of the signal received through the antenna, and the data rate parameter indicates the data rate of the received signal.

The service primitive associated with the RXVECTOR 2360 parameter is PHY-RXSTART.indication. That is, the RXVECTOR 2360 is used as an argument of the function called PHY-RXSTART.indication.

As such, in order to interwork the PLCP sublayer 2312 and the MAC layer 2320, the physical layer 2310 defines TXVECTOR 2370 and RXVECTOR 2360 as service primitive parameters.

In particular, IEEE 802.11n defines a High Throughput (HT) operation that provides higher data rates than IEEE 802.11a / g using channel bandwidths of 20 MHz and 40 MHz. Accordingly, the PHY service parameters of the IEEE 802.11n are defined based on channel bandwidths of 20 MHz and 40 MHz.

Table 1 below shows some parameters of TXVECTOR and RXVECTOR as defined in IEEE 802.11n. That is, Table 1 below shows only the format (FORMAT), channel bandwidth (CH_BANDWIDTH) and channel offset (CH_OFFSET) related to an embodiment of the present invention. The TXVECTOR and RXVECTOR may further include parameters such as NON_HT_MODULATION, L_LENGTH, L_DATARATE, LSIGVALID, SERVICE, TXPWR_LEVEL, RSSI, MCS, etc. in addition to the format, channel bandwidth, and channel offset.

Table 1

Para meter	Condition	Value	TXVECTOR	RXVECTOR
			See NOTE1
FORMAT		Determines the format of the PPDU.Enumerated type: NON_HT indicates Clause 15, Clause 17, Clause 18, or Clause 19PPDU formats or non-HT duplicated PPDU format. In this case, themodulation is determined by the NON_HT_MODULATION parameter. HT_MF indicates HT-mixed format. HT_GF indicates HT-greenfield format.	Y	Y
CH_BANDWIDTH	FORMAT is HT_MF or HF_GF	Indicates whether the packet is transmitted using 40 MHz or 20 MHz channel width.Enumerated type: HT_CBW20 for 20 MHz and 40 MHz upper and 40 MHz lower modesHT_CBW40 for 40 MHz	Y	Y
	FORMAT is NON_HT	Enumerated type: NON_HT_CBW40 for non-HT duplicate format	Y	Y
CH_OFFSET		Indicates which portion of the channel is used for transmission. Refer to Table 20-2 for valid combinations of CH_OFFSET and CH_BANDWIDTH.Enumerated type: CH_OFF_20 indicates the use of a 20 MHz channel (that is not part of a 40 MHz channel) .CH_OFF_40 indicates the entire 40 MHz channel.CH_OFF_20U indicates the upper 20 MHz of the 40 MHz channel.CH_OFF_20L indicates the lower 20 MHz of the 40 MHz channel.	Y	N
NOTE 1: In the “TXVECTOR” and “RXVECTOR” columns, the following apply: Y = Present; N = Not present; O = Optional

            

Referring to Table 1, the TXVECTOR includes information on format, channel bandwidth, and channel offset. The RXVECTOR includes information about a format and a channel bandwidth.

Among the parameters, the format parameter determines the type of PLCP protocol data unit (hereinafter referred to as 'PPDU') to be generated in the physical layer 2310. The type of the PPDU may be one of three modes: Non-HT format (NON_HT), HT-mixed format (HT_MF), and HT-greenfield format (HT_GF).

Among the formats of the PPDU, the NON_HT is a structure of a packet (or frame) to which a high throughput (HT) operation is not applied, such as IEEE 802.11a / g. Therefore, the NON_HT may be compatible with a station using IEEE802.11a / g. Meanwhile, the term frame or packet is used to refer to the PPDU, but is not limited thereto.

The HT_MF has a high throughput (HT) operation of IEEE 802.11n, and is a packet structure compatible with existing IEEE 802.11a / g. That is, the HT_MF has a structure in which a packet of a legacy format and a packet of a HT format are combined.

More specifically, the HT_MF is configured using the Non-HT format from legacy-STF (L-STF) to legacy-SIG (L-SIG), and subsequent signals are configured using the HT format. Can be.

The HF_GF is not compatible with the existing IEEE 802.11a / g and is a packet structure to which only a high throughput (HT) operation of IEEE 802.11n is applied.

Information about these format parameters is included in the TXVECTOR and RXVECTOR, respectively (TXVECTOR = Y, RXVECTOR = Y).

The channel bandwidth (CH_BANDWIDTH) parameter indicates whether a packet is transmitted using a channel bandwidth of 40 MHz or 20 MHz.

The channel bandwidth is further divided into two conditions according to the format of the packet. The first condition is a case where the format of the packet is HT-mixed format (HT_MF) or HT-greenfield format (HT_GF), and the second condition is when the format of the packet is Non-HT format (NON_HT).

When the first condition "packet format is HT_MF or HT_GF", the TXVECTOR and RXVECTOR include information on which channel bandwidth the packet is transmitted (TXVECTOR = Y, RXVECTOR = Y). Here, the information relates to which channel bandwidth of the packet is transmitted using 20 MHz or 40 MHz.

In particular, when the packet is transmitted using a channel bandwidth of 20 MHz, the channel bandwidth HT_CBW20 may be any one of a channel band of 20 MHz, an upper channel band of 40 MHz, and a lower channel band of 40 MHz. It may be a channel band of.

In addition, when the second condition "packet format is NON_HT", the TXVECTOR and RXVECTOR includes information on which channel bandwidth of the legacy format packet is transmitted (TXVECTOR = Y, RXVECTOR = Y) . Here, the information relates to which channel bandwidth of the packet is transmitted using 20 MHz or 40 MHz.

Meanwhile, the channel offset (CH_OFFSET) parameter indicates which part of the channel is used for packet transmission.

In the HT operation of IEEE 802.11n, one 40 MHz channel may be divided into two 20 MHz channels, an upper channel and a lower channel. Among these, one channel may be set as a primary channel and the other channel may be set as a secondary channel. Here, although the primary channel can be used for packet transmission, the difference is that the secondary channel cannot be used for packet transmission. Accordingly, the channel offset parameter indicates which of the upper channel of 20 MHz and the lower channel of 20 MHz is the main channel.

For example, in Table 1, "CH_OFF_20" indicates that the packet is transmitted using a 20 MHz channel, rather than part of a 40 MHz channel, and "CH_OFF_40" indicates that the packet is transmitted using a full band of a 40 MHz channel. do.

And, "CH_OFF_20U" indicates that the packet is transmitted using the upper channel of the 40MHz channel, "CH_OFF_20L" indicates that the packet is transmitted using the lower channel of the 40MHz channel.

On the other hand, the channel offset parameter is included in the TXVECTOR, but not in the RXVECTOR (TXVECTOR = Y, RXVECTOR = N).

As such, IEEE 802.11n only defines the High Throughput (HT) operation for a channel bandwidth of 20 MHz or 40 MHz, but does not define the High Throughput (HT) operation for 5 MHz and 10 MHz channels.

However, the wireless LAN system using the TVWS is expected to perform communication using the channel bandwidth of 5MHz and 10MHz as well as the channel bandwidth of the 20MHz and 40MHz. Therefore, the IEEE 802.11n needs to define the HT operation for the 5MHz and 10MHz channels.

Table 2 below shows some parameters of the newly defined TXVECTOR and RXVECTOR for applying HT operation to 5 MHz and 10 MHz channels according to an embodiment of the present invention. In the following Table 2, the underlined parts are newly defined parts for the HT operation in the 5 MHz and 10 MHz channels, and the rest are parts defined in Table 1 above.

TABLE 2

Para meter	Condition	Value	TXVECTOR	RXVECTOR
			See NOTE1
FORMAT		Determines the format of the PPDU.Enumerated type: NON_HT indicates Clause 15, Clause 17, Clause 18, or Clause 19PPDU formats or non-HT duplicated PPDU format. In this case, themodulation is determined by the NON_HT_MODULATION parameter. HT_MF indicates HT-mixed format. HT_GF indicates HT-greenfield format.	Y	Y
CH_BANDWIDTH	FORMAT is HT_MF or HF_GF	Indicates whether the packet is transmitted using 40 MHz, 20 MHz, 10MHz or 5MHz channel width.Enumerated type: HT_CBW20 for 20 MHz and 40 MHz upper and 40 MHz lower modesHT_CBW40 for 40 MHz HT_CBW10 for 10 MHz HT_CBW5 for 5 MHz	Y	Y
	FORMAT is NON_HT	Enumerated type: NON_HT_CBW40 for non-HT duplicate formatNON_HT_CBW20 for all other non-HT formats NON_HT_CBW10 for all non-HT formats in 10 MHz channel NON_HT_CBW5 for all non-HT formats in 5 MHz channel	Y	Y
CH_OFFSET		Indicates which portion of the channel is used for transmission. Refer to Table 20-2 for valid combinations of CH_OFFSET and CH_BANDWIDTH.Enumerated type: CH_OFF_20 indicates the use of a 20 MHz channel (that is not part of a 40 MHz channel) .CH_OFF_40 indicates the entire 40 MHz channel.CH_OFF_20U indicates the upper 20 MHz of the 40 MHz channel.CH_OFF_20L indicates the lower 20 MHz of the 40 MHz channel. CH_OFF_10 indicates the use of 10 MHz channel . CH_OFF_5 indicates the use of 5MHz channel .	Y	N
NOTE 1: In the “TXVECTOR” and “RXVECTOR” columns, the following apply: Y = Present; N = Not present; O = Optional

Referring to Table 2, the TXVECTOR and RXVECTOR include information on the new channel bandwidth and channel offset to enable HT operation in 5MHz and 10MHz channels.

The channel bandwidth CH_BANDWIDTH parameter according to an embodiment of the present invention indicates whether a packet is transmitted using a channel bandwidth of 40 MHz, 20 MHz, 10 MHz, and 5 MHz. First, among the channel bandwidth CH_BANDWIDTH, When the first condition "packet format is HT_MF or HT_GF", the TXVECTOR and RXVECTOR further include channel bandwidth information for 5MHz and 10MHz channels, respectively (TXVECTOR = Y, RXVECTOR = Y).

For example, the channel bandwidth parameter defines “HT_CBW10” to indicate that a packet of HT format is transmitted using a channel bandwidth of 10 MHz. In addition, the channel bandwidth parameter defines "HT_CBW5" to indicate that the packet of the HT format is transmitted using a channel bandwidth of 5MHz.

In addition, when the second condition "packet format is NON_HT", the TXVECTOR and RXVECTOR further includes channel bandwidth information for each of the 5MHz and 10MHz channels (TXVECTOR = Y, RXVECTOR = Y).

For example, the channel bandwidth parameter defines “NON_HT_CBW10” to indicate that a packet having a non-HT format is transmitted using a channel bandwidth of 10 MHz. In addition, the channel bandwidth parameter defines “NON_HT_CBW5” to indicate that the packet of the Non-HT format is transmitted using a channel bandwidth of 5 MHz.

Meanwhile, the channel offset (CH_OFFSET) parameter according to an embodiment of the present invention indicates which part of the channel is used for packet transmission for each of channel bandwidths of 40 MHz, 20 MHz, 10 MHz, and 5 MHz. However, the 5 MHz and 10 MHz channels are used for the entire band for packet transmission, and no part of a specific channel is used.

For example, in Table 2, "CH_OFF_10" indicates that the packet is transmitted using the full band of the 10MHz channel. And, "CH_OFF_5" indicates that the packet is transmitted using the entire band of the 5MHz channel.

In addition, the channel offset parameter is included in the TXVECTOR but not the RXVECTOR. That is, the TXVECTOR further includes channel offset information for each of the 5 MHz and 10 MHz channels, but the RXVECTOR does not include channel offset information for each of the 5 MHz and 10 MHz channels (TXVECTOR = Y, RXVECTOR = N).

Meanwhile, the structure of the PPDU transmitted by the WLAN device is determined by the format parameter, channel bandwidth parameter, channel offset parameter, and modulation and coding scheme (MCS) parameter of the TXVECTOR. In particular, the physical layer operation in the frequency domain is determined by the channel bandwidth parameter and the channel offset parameter.

Table 3 below shows the function of channel bandwidth parameters and channel offset parameters of newly defined TXVECTOR and RXVECTOR according to an embodiment of the present invention.

In the following Table 3, the underlined parts are newly defined parts for HT operation in the 5MHz and 10MHz channels, and the rest are parts defined in the existing IEEE 802.11n.

TABLE 3

CH_BANDWIDTH	CH_OFFSET
HT_CBW20	CH_OFF_20 or CH_OFFSET is not present: 20 MHz HT format -A STA that has a 20 MHz operating channel width transmits an HT-mixed or HT-greenfield format packet of 20 MHz bandwidth with one to four spatial streams.CH_OFF_40: Not defined CH_OFF_20U: 40 MHz HT upper format- The STA transmits an HT-mixed or HT-greenfield format packet of 20 MHz bandwidth with one to four spatial streams in the upper 20 MHz of a 40 MHz channel.CH_OFF_20L: 40 MHz HT lower format- The STA transmits an HT-mixed or HT-greenfield format packet of 20 MHz bandwidth with one to four spatial streams in the lower 20 MHz of a 40 MHz channel. CH_OFF_10: Not defined CH_OFF_5: Not defined
HT_CBW40	Not present: Not defined CH_OFF_20: Not defined CH_OFF_40: 40 MHz HT format- A PPDU of this format occupies a 40 MHz channel to transmit an HT-mixed or HT-greenfield format packet of 40 MHz bandwidth with one to four spatial streams.CH_OFF_20U : Not defined CH_OFF_20L: Not defined CH_OFF_10: Not defined CH_OFF_5: Not defined
HT_CBW10	CH_OFF_10 or CH_OFFSET is not present: 10 MHz HT format- A STA that has a 10 MHz operating channel width transmits an HT-mixed or HT-greenfield format packet of 10 MHz bandwidth with one to four spatial streams. CH_OFF_20: Not defined CH_OFF_40: Not defined CH_OFF_20U: Not defined CH_OFF_20L: Not defined CH_OFF_5: Not defined
HT_CBW5	CH_OFF_5 or CH_OFFSET is not present: 5 MHz HT format- A STA that has a 5 MHz operating channel width transmits an HT-mixed or HT-greenfield format packet of 5 MHz bandwidth with one to four spatial streams. CH_OFF_20: Not defined CH_OFF_40: Not defined CH_OFF_20U: Not defined CH_OFF_20L: Not defined CH_OFF_10: Not defined
NON_HT_CBW20	CH_OFF_20 or CH_OFFSET is not present: 20 MHz non-HT format- A STA that has a 20 MHz operating channel width transmits a non-HT format packet according to Clause 17 or Clause 19 operation.CH_OFF_40: Not defined CH_OFF_20U: 40 MHz non- HT upper format- The STA transmits a non-HT packet of type ERP-DSSS, ERP-CCK, ERP-OFDM, ERP-PBCC, DSSS-OFDM, or OFDM in the upper 20 MHz of a 40 MHz channel.CH_OFF_20L: 40 MHz non-HT lower format- The STA transmits a non-HT packet of type ERP-DSSS, ERP-CCK, ERP-OFDM, ERP-PBCC, DSSS-OFDM, or OFDM in the lower 20 MHz of a 40 MHz channel. CH_OFF_10: Not defined CH_OFF_5: Not defined
NON_HT_CBW40	Not present: Not defined CH_OFF_20: Not defined CH_OFF_40: Non-HT duplicate format- The STA operates in a 40 MHz channel composed of two adjacent 20 MHz channels. The packets to be sent are in the Clause 17 format in each of the 20 MHz channels. The upper channel (higher frequency) is rotated by + 90 ° relative to the lower channel. See 20.3.11.11.CH_OFF_20U: Not defined CH_OFF_20L: Not defined CH_OFF_10 : Not defined CH_OFF_5: Not defined
NON_HT_CBW10	CH_OFF_10 or CH_OFFSET is not present: 10 MHz non-HT format- A STA that has a 10 MHz operating channel width transmits a non-HT format packet according to Clause 17 or Clause 19 operation. CH_OFF_20: Not defined CH_OFF_40: Not defined CH_OFF_20U: Not defined CH_OFF_20L: Not defined CH_OFF_5: Not defined
NON_HT_CBW5	CH_OFF_5 or CH_OFFSET is not present: 5 MHz non-HT format -A STA that has a 5 MHz operating channel width transmits a non-HT format packet according to Clause 17 or Clause 19 operation. CH_OFF_20: Not defined CH_OFF_40: Not defined CH_OFF_20U: Not defined CH_OFF_20L: Not defined CH_OFF_10: Not defined

Referring to Table 3, the channel bandwidth (CH_BANDWIDTH) parameter further includes HT_CBW10, HT_CBW5, NON_HT_CBW10 and NON_HT_CBW5 for HT operation on 5 MHz and 10 MHz channels.

In addition, the channel offset (CH_OFFSET) parameter further includes CH_OFF_10 and CH_OFF_5 for HT operation in the newly defined 5MHz and 10MHz channel.

First, when the channel bandwidth parameter is HT_CBW20, the channel offset parameter defines “CH_OFF_20 or CH_OFF is not present”, “CH_OFF_20U” and “CH_OFF_20L”, and defines about “CH_OFF_40”, “CH_OFF_10” and “CH_OFF_5”. I never do that.

Among the channel offset parameters, “CH_OFF_20 or CH_OFF is not present” indicates that a station having an operating channel of 20 MHz transmits a packet of HT format having a channel bandwidth of 20 MHz. Here, “CH_OFF is not present” means a case where a channel offset parameter does not exist.

In addition, the "CH_OFF_20U" indicates that the station transmits a packet of the HT format having a channel bandwidth of 20MHz in the upper channel of the 40MHz channel, the "CH_OFF_20L" indicates an HT format having a channel bandwidth of 20MHz in the lower channel of the 40MHz channel Indicates to send a packet.

When the channel bandwidth parameter is HT_CBW40, the channel offset parameter defines “CH_OFF_40” and does not define “Not present”, “CH_OFF_20”, “CH_OFF_20U”, “CH_OFF_20L”, “CH_OFF_10”, and “CH_OFF_5”. .

Among the channel offset parameters, "CH_OFF_40" indicates that a station having an operating channel of 40 MHz transmits a packet of HT format having a channel bandwidth of 40 MHz.

When the channel bandwidth parameter is HT_CBW10, the channel offset parameter defines “CH_OFF_10 or CH_OFF is not present” and does not define “CH_OFF_40”, “CH_OFF_20”, “CH_OFF_20U”, “CH_OFF_20L”, and “CH_OFF_5”. .

Among the channel offset parameters, "CH_OFF_10 or CH_OFF is not present" indicates that a station having an operating channel of 10 MHz transmits a packet of HT format having a channel bandwidth of 10 MHz.

When the channel bandwidth parameter is HT_CBW5, the channel offset parameter defines “CH_OFF_5 or CH_OFF is not present” and does not define “CH_OFF_40”, “CH_OFF_20”, “CH_OFF_20U”, “CH_OFF_20L”, and “CH_OFF_10”. .

Among the channel offset parameters, "CH_OFF_5 or CH_OFF is not present" indicates that a station having an operating channel of 5 MHz transmits a packet of HT format having a channel bandwidth of 5 MHz.

Meanwhile, when the channel bandwidth parameter is NON_HT_CBW20, the channel offset parameter defines “CH_OFF_20 or CH_OFF is not present”, “CH_OFF_20U” and “CH_OFF_20L”, and defines about “CH_OFF_40”, “CH_OFF_10”, and “CH_OFF_5”. I never do that.

Among the channel offset parameters, “CH_OFF_20 or CH_OFF is not present” indicates that a station having an operating channel of 20 MHz transmits a packet in a Non-HT format having a channel bandwidth of 20 MHz. Here, “CH_OFF is not present” means a case where a channel offset parameter does not exist.

And, "CH_OFF_20U" indicates that the station transmits a non-HT format packet having a channel bandwidth of 20MHz in the upper channel of the 40MHz channel, the "CH_OFF_20L" has a channel bandwidth of 20MHz in the lower channel of the 40MHz channel Indicates the transmission of packets in non-HT format.

When the channel bandwidth parameter is NON_HT_CBW40, the channel offset parameter defines “CH_OFF_40” and does not define “Not present”, “CH_OFF_20”, “CH_OFF_20U”, “CH_OFF_20L”, “CH_OFF_10”, and “CH_OFF_5”. .

Among the channel offset parameters, "CH_OFF_40" indicates that a station having an operating channel of 40 MHz transmits a packet having a non-HT format packet having a channel bandwidth of 40 MHz.

When the channel bandwidth parameter is NON_HT_CBW10, the channel offset parameter defines “CH_OFF_10 or CH_OFF is not present” and does not define “CH_OFF_40”, “CH_OFF_20”, “CH_OFF_20U”, “CH_OFF_20L”, and “CH_OFF_5”. .

Among the channel offset parameters, “CH_OFF_10 or CH_OFF is not present” indicates that a station having an operating channel of 10 MHz transmits a packet of a Non-HT format having a channel bandwidth of 10 MHz.

When the channel bandwidth parameter is NON_HT_CBW5, the channel offset parameter defines “CH_OFF_5 or CH_OFF is not present” and does not define “CH_OFF_40”, “CH_OFF_20”, “CH_OFF_20U”, “CH_OFF_20L”, and “CH_OFF_10”. .

Among the channel offset parameters, “CH_OFF_5 or CH_OFF is not present” indicates that a station having an operating channel of 5 MHz transmits a packet of a Non-HT format having a channel bandwidth of 5 MHz.

As described above, when the channel bandwidth parameters are HT_CBW20, NON_HT_CBW20, HT_CBW40, and NON_HT_CBW40, the channel offset parameters corresponding to the channel bandwidth parameters add "CH_OFF_10" and "CH_OFF_5". Here, the added content is that "CH_OFF_10" and "CH_OFF_5" are not defined in the corresponding channel bandwidth.

In addition, the channel bandwidth parameter newly defines HT_CBW10, NON_HT_CBW10, HT_CBW5 and NON_HT_CBW5 for HT operation in 5 MHz and 10 MHz channels. In addition, the channel offset parameter corresponding to the newly defined channel bandwidth parameter is further defined.

FIG. 24 illustrates a flow of a procedure for performing HT operation and non-HT operation in a 5 MHz channel and a 10 MHz channel using TXVECTOR input to the PHY service interface (or PHY SAP) of FIG. 23.

Referring to FIG. 24, in step 2401, the PHY service interface receives a TXVECTOR from a MAC layer and delivers it to a physical layer.

Then, in step 2403, the controller checks the format of the packet to be transmitted using the format parameter of the TXVECTOR.

Next, in step 2405, the controller checks whether the format of the inspected packet is a non-HT format.

As a result of the check, if the format of the packet is Non-HT, the flow proceeds to step 2423 to check the channel bandwidth of the packet. On the other hand, if the format of the packet is not Non-HT, that is, the format of the packet is HT-MF or HT-GF, go to step 2407 to check the channel bandwidth of the packet.

First, if the format of the packet is not Non-HT, in step 2409, the PHY service interface checks whether the checked channel bandwidth is 5MHz.

As a result of the check, if the channel bandwidth of the packet is 5 MHz, the process proceeds to step 2411 and checks the channel offset corresponding to the channel bandwidth. On the other hand, if the channel bandwidth is not 5MHz, that is, if the channel bandwidth of the packet is 10MHz, go to step 2417 to check the channel offset corresponding to the channel bandwidth.

If the channel bandwidth of the packet is 5MHz, in step 2413, the PHY service interface checks whether the checked channel offset is CH_OFF_5.

As a result of the check, when the channel offset is CH_OFF_5, the process proceeds to step 2415 to perform an HT operation with a channel bandwidth of 5 MHz. Although not shown in FIG. 24, even when the channel offset does not exist (CH_OFF is not present), the method proceeds to step 2415 to perform the HT operation with a channel bandwidth of 5 MHz.

On the other hand, if the channel offset is not CH_OFF_5, that is, if the channel offset is CH_OFF_40, CH_OFF_20, CH_OFF_20U, CH_OFF_20L or CH_OFF_10, the procedure is terminated.

If the channel bandwidth of the packet is not 5MHz, that is, the channel bandwidth of the packet is 10MHz, in step 2419, the PHY service interface checks whether the checked channel offset is CH_OFF_10.

As a result of the check, when the channel offset is CH_OFF_10, the process proceeds to step 2421 to perform an HT operation with a channel bandwidth of 10 MHz. Although not shown in FIG. 24, even when the channel offset does not exist (CH_OFF is not present), the method may proceed to step 2421 to perform the HT operation with a channel bandwidth of 10 MHz.

On the other hand, if the channel offset is not CH_OFF_10, that is, if the channel offset is CH_OFF_40, CH_OFF_20, CH_OFF_20U, CH_OFF_20L or CH_OFF_5, the procedure is terminated separately.

As a result of checking in step 2405, if the format of the packet is Non-HT, the flow proceeds to step 2423 to check the channel bandwidth of the packet. In step 2425, the PHY service interface checks whether the checked channel bandwidth is 5 MHz.

As a result of the check, if the channel bandwidth of the packet is 5 MHz, the flow proceeds to step 2427 to check the channel offset corresponding to the channel bandwidth. On the other hand, if the channel bandwidth of the packet is not 5MHz, that is, if the channel bandwidth of the packet is 10MHz, go to step 2433 to check the channel offset.

If the channel bandwidth of the packet is 5MHz, in step 2429, the PHY service interface checks whether the checked channel offset is CH_OFF_5.

As a result of the check, when the channel offset is CH_OFF_5, the process proceeds to step 2431 and performs a non-HT operation with a channel bandwidth of 5 MHz. Although not shown in FIG. 24, even when the channel offset does not exist (CH_OFF is not present), the process may proceed to step 2431 to perform a Non-HT operation with a channel bandwidth of 5 MHz.

On the other hand, if the channel offset is not CH_OFF_5, that is, if the channel offset is CH_OFF_20, CH_OFF_40, CH_OFF_20U, CH_OFF_20L or CH_OFF_10, the procedure is terminated separately.

If the channel bandwidth is not 5MHz, in step 2435, the PHY service interface checks whether the checked channel offset is CH_OFF_10.

As a result of the check, if the channel offset is CH_OFF_10, the flow proceeds to step 2437 to perform a Non-HT operation with a channel bandwidth of 10 MHz. Although not shown in FIG. 24, even when the channel offset does not exist (CH_OFF is not present), the method may proceed to step 2437 to perform a non-HT operation with a channel bandwidth of 10 MHz.

On the other hand, if the channel offset is not CH_OFF_10, that is, if the channel offset is CH_OFF_20, CH_OFF_40, CH_OFF_20U, CH_OFF_20L or CH_OFF_5, the procedure is terminated.

The physical layer configures and transmits a packet according to the format, channel bandwidth, and channel offset of the TXVECTOR identified by the controller.

FIG. 25 illustrates a flow of a procedure for performing HT operation and non-HT operation in a 5 MHz channel and a 10 MHz channel by using an RXVECTOR input to the PHY service interface (or PHY SAP) of FIG. 23.

Referring to FIG. 25, in step 2501, the PHY service interface receives an RXVECTOR from a PLCP sublayer and delivers it to a MAC layer.

Thereafter, in step 2503, the controller checks the format of the received packet using the format parameter of the RXVECTOR.

Next, in step 2505, the controller checks whether the format of the inspected packet is a non-HT format.

As a result of the check, if the format of the packet is Non-HT, the flow proceeds to step 2515 to check the channel bandwidth of the packet. On the other hand, if the format of the packet is not Non-HT, that is, the format of the packet is HT-MF or HT-GF, go to step 2507 to check the channel bandwidth of the packet.

First, if the format of the packet is not Non-HT, in step 2509, the PHY service interface checks whether the checked channel bandwidth is 5MHz.

As a result of the check, if the channel bandwidth of the packet is 5 MHz, the flow proceeds to step 2511 to perform an HT operation with a channel bandwidth of 5 MHz. On the other hand, if the channel bandwidth of the packet is not 5MHz, that is, if the channel bandwidth of the packet is 10MHz, go to step 2513 to perform the HT operation with a channel bandwidth of 10MHz.

Although not shown in FIG. 25, when the channel bandwidth of the packet is 20 MHz or 40 MHz, the HT operation may be performed with the corresponding channel bandwidth.

As a result of checking in step 2505, if the format of the packet is Non-HT, the flow proceeds to step 2515 to check the channel bandwidth of the packet. In step 2517, the PHY service interface determines whether the checked channel bandwidth is 5 MHz.

As a result of the check, if the channel bandwidth of the packet is 5MHz, the process moves to step 2519 and performs a non-HT operation with a channel bandwidth of 5MHz. On the other hand, if the channel bandwidth of the packet is not 5MHz, that is, if the channel bandwidth of the packet is 10MHz, go to step 2521 to perform a non-HT operation with a channel bandwidth of 10MHz.

Meanwhile, although not shown in FIG. 25, when the channel bandwidth of the packet is 20 MHz or 40 MHz, a non-HT operation may be performed with the corresponding channel bandwidth.

The MAC layer finds information on the packet received from the physical layer based on the format and channel bandwidth of the RXVECTOR identified by the controller.

As described above, according to another embodiment of the present invention, wireless LAN devices using a TV white space band may perform high-throughput (HT) operation defined in IEEE 802.11n as well as channel bandwidths of 20 MHz and 40 MHz, as well as 5 MHz and 10 MHz. It can also be performed in the channel bandwidth of.

That is, the wireless LAN device using the conventional TVWS performs the HT operation using a channel bandwidth of 20MHz or 40MHz for high-speed data transmission. However, as described above, the TV channel unit in the TV white space band may be 6 MHz, 7 MHz, or 8 MHz, etc., depending on the region and country, for example, 6 MHz per channel in the United States.

Therefore, in order to perform the HT operation using a channel bandwidth of 20 MHz or 40 MHz, the WLAN device using the existing TVWS should have four or more empty TV channels in a row.

For example, in the United States, at least four channels must be empty in order for the existing wireless LAN device to perform HT operation using a channel bandwidth of 20 MHz, and at least seven channels must be used to perform HT operation using a channel bandwidth of 40 MHz. The above channels must be empty.

However, since another embodiment of the present invention defines HT (High Throughput) operation for channels of 5 MHz and 10 MHz, the HT operation can be performed even if only a few TV channels are empty.

For example, when a wireless LAN device using a TVWS of 6 MHz unit communicates using a channel bandwidth of 5 MHz, the wireless LAN device may use a corresponding channel for high-speed data transmission even if only one TV channel is empty. HT operation can be performed.

In addition, when a wireless LAN device using a TVWS of 6 MHz unit communicates using a channel bandwidth of 10 MHz, the wireless LAN device may use a corresponding channel for high-speed data transmission even if only two TV channels are empty. HT operation can be performed.

Accordingly, the WLAN apparatus according to an embodiment of the present invention can effectively perform an HT operation for high speed data transmission using a small number of empty TV channels.

As described above, at least some of the transmission and reception methods according to the exemplary embodiment of the present invention may be stored in a computer-readable recording medium that is produced as a program to be executed in a computer. ROMs, RAMs, CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, and the like, and also include those implemented in the form of carrier waves (eg, transmission over the Internet).

The computer readable recording medium can be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, codes, and code segments for implementing the method can be easily inferred by programmers in the art to which the present invention belongs.

On the other hand, while the specific embodiments of the present invention have been described, various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims below, but also by those equivalent to the claims.

That is, the detailed description of the above-described invention shows an implementation example applied to a wireless LAN system using a TV white space. However, the present invention can be applied to other wireless communication systems using similar technical backgrounds and TV white spaces without departing from the scope of the present invention, which can be determined by those skilled in the art. It will be possible.

Claims (20)

1. A transmission method of a wireless LAN device for performing a high throughput (HT) operation using a TV white space band,

   Receiving a TXVECTOR from a medium access control (MAC) layer including information on a packet to be transmitted;

   Checking a format parameter of the received TXVECTOR;

   Examining a channel bandwidth parameter and a channel offset parameter of the TXVECTOR according to the identified format parameter; And

   Transmitting a packet formed based on the identified format and the checked channel bandwidth and channel offset.
2. The method of claim 1,

   The format parameter includes information on the type of the packet, and the type of the packet is any one of a non-HT format, an HT-mixed format, and a HT-greenfield format.
3. The method of claim 1,

   The channel bandwidth parameter includes information on which channel bandwidth of the packet is transmitted using a channel bandwidth of 10 MHz and 5 MHz.
4. The method of claim 3,

   The channel offset parameter includes channel offset information on which part of a channel a packet corresponding to the channel bandwidth parameter is transmitted.
5. The method of claim 4, wherein

   The channel offset information includes information for indicating that the packet is transmitted using a full band of a 5 MHz channel, and information for indicating that the packet is transmitted using a full band of a 10 MHz channel. Transmission method.
6. The method of claim 1,

   The packet is a transmission method characterized in that the PLCP Protocol Physical Unit Convergence Procedure Sublayer Protocol Data Unit (PPDU) to be transmitted by the WLAN device.
7. A transmitting apparatus of a wireless LAN apparatus for performing a high throughput (HT) operation using a TV white space band,

   A PHY service interface for receiving a TXVECTOR from a Medium Access Control (MAC) unit including information about a packet to be transmitted;

   A controller for checking a format parameter of the TXVECTOR received from the PHY service interface and checking a channel bandwidth and a channel offset of the TXVECTOR according to the identified format parameter; And

   And a PHY unit for transmitting a packet formed based on the checked format and the checked channel bandwidth and channel offset.
8. The method of claim 7, wherein

   The format parameter includes information on the type of the packet, wherein the type of the packet is any one of a non-HT format, HT-mixed format and HT-greenfield format.
9. The method of claim 7, wherein

   The channel bandwidth parameter comprises information on which channel bandwidth of the packet is transmitted using a channel bandwidth of 10 MHz and 5 MHz.
10. The method of claim 9,

    The channel offset parameter includes channel offset information on which part of a channel a packet corresponding to the channel bandwidth parameter is transmitted.
11. The method of claim 10,

    The channel offset information includes information for indicating that the packet is transmitted using a full band of a 5 MHz channel, and information for indicating that the packet is transmitted using a full band of a 10 MHz channel. Transmitting device.
12. The method of claim 7, wherein

    The packet is a transmission device, characterized in that the physical layer convergence procedure Sublayer Protocol Data Unit (PPDU) to be transmitted by the wireless LAN device.
13. A reception method of a wireless LAN device for performing a high throughput (HT) operation using a TV white space band,

    Receiving from the physical layer an RXVECTOR that includes information about the received packet;

    Checking a format parameter of the received RXVECTOR;

    Checking a channel bandwidth parameter of the RXVECTOR according to the identified format parameter; And

    Analyzing the received packet using the identified format and the checked channel bandwidth.
14. The method of claim 13,

    The format parameter includes information on the type of the packet, and the type of the packet is one of a non-HT format, a HT-mixed format, and a HT-greenfield format.
15. The method of claim 13,

    The channel bandwidth parameter comprises information on which channel bandwidth of the packet is received using a channel bandwidth of 10 MHz and 5 MHz.
16. The method of claim 13,

    The packet is a reception method, characterized in that the physical layer convergence procedure sublayer protocol data unit (PPDU) received by the wireless LAN device.
17. A reception apparatus of a wireless LAN apparatus for performing a high throughput (HT) operation using a TV white space band,

    A PHY service interface for receiving from the physical layer an RXVECTOR that contains information about the received packet;

    A controller for checking a format parameter of the RXVECTOR received from the PHY service interface and checking a channel bandwidth parameter of the RXVECTOR according to the identified format parameter; And

    And a medium access control (MAC) unit for analyzing the received packet using the checked format and the checked channel bandwidth.
18. The method of claim 17,

    The format parameter includes information on the type of the packet, wherein the type of the packet is any one of a non-HT format, HT-mixed format and HT-greenfield format.
19. The method of claim 17,

    And the channel bandwidth parameter includes information on which channel bandwidth of the packet is received using a channel bandwidth of 10 MHz and 5 MHz.
20. The method of claim 17,

    And the packet is a PLCP protocol data unit (PPDU) received by the WLAN device.

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