KR101740567B1 - Apparatus and method for transmitting with multiple antenna or multiple bandwidth - Google Patents

Abstract

A signal transmission / reception value and a method are disclosed. The present invention relates to a stream and segment parser that operates as a segment parser when converted to a first mode and operates as a stream parser when converted to a second mode; A preamble generator for transmitting one VHT-LTF field when converted into the first mode, and transmitting a plurality of VHT-LTF fields when the second mode is converted; A PLL for setting a carrier frequency of the predetermined bandwidth signal to an output frequency when the mode is converted into the first mode and outputting the same carrier if the carrier frequency is converted into the second mode; And an output unit which combines all the input signals when the mode is converted into the first mode and transmits the combined signals to one antenna and transmits the input signals to the plurality of antennas when the mode is converted into the second mode. According to the present invention, both a multi-antenna single-bandwidth mode and a single-antenna multi-bandwidth mode can be provided or provided through a single modem structure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and a method for transmitting multiple antennas or multi-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to wireless communications, and more particularly to a method and apparatus for transmitting over multiple antennas or multiple bandwidths.

In order to improve the transmission rate in a wireless LAN (Local Access Network) system, a new standard adopting multi-antenna technology and multi-bandwidth technology is proposed. Typical examples are Institute of Electrical and Electronics Engineers (IEEE) 802.11n and IEEE 802.11ac. IEEE 802.11n defines up to 40 MHz bandwidth, 4 transmit data streams, and IEEE 802.11ac defines 160 MHz bandwidth and 8 transmit streams.

It is required to utilize a large bandwidth and a large number of antennas in order to realize a maximum transmission rate. However, there are practical limitations on the available bandwidth and the number of antennas. Therefore, a system having a configuration in which the available bandwidth and the number of antennas are appropriately combined can be configured. For example, one modem may be configured, which is capable of both wideband transmission with a small number of transmit antennas and narrowband transmission with a large number of transmit antennas.

On the other hand, an 80 + 80MHz bandwidth mode, which is supported indispensably from IEEE 802.11ac to 80MHz bandwidth and supports two consecutive 160MHz bandwidth modes or two non-consecutive 80MHz bandwidths, is optionally supported. At this time, there are advantages and disadvantages in modes in which the same data rate is obtained by increasing the number of transmission data streams to two through two antennas while using a mode using a 160 MHz bandwidth and an 80 MHz bandwidth. For example, in the case of a terminal without space limitation, it may be more effective to provide high-speed data service using a multi-antenna technology than to use a wide bandwidth of 160 MHz in a limited channel resource environment. For these two environments, it is cost effective to design a single modem structure that can support both modes while keeping the modem structure similar to the previous one.

Accordingly, a method and a device for determining a transmission mode according to a situation of a communication device by providing a mode for transmitting using a single antenna in a bandwidth of 160 MHz and a mode for transmitting using two transmission antennas in an 80 MHz bandwidth through a single modem structure Is required.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for supporting a multi-antenna mode and a multi-bandwidth mode.

It is another object of the present invention to provide a method and apparatus for selectively supporting a multi-antenna mode or a multi-bandwidth mode.

According to one aspect of the present invention, a signal transmitting apparatus includes: a stream and segment parser operating as a segment parser in a first mode and operating as a stream parser in a second mode; A cyclic shift diversity (CSD) generating a temporal cyclic delay for each of the antennas so that signals transmitted from the respective antennas have different phase shifts in the second mode; (VHT-LTF) field including an OFDM (Orthogonal Frequency Division Multiplexing) symbol of a predetermined pattern in the first mode, and transmits a plurality of VHT-LTF fields A preamble generator for transmitting the preamble; A PLL (Phase Locked Loop) for setting each carrier frequency of a predetermined bandwidth signal to an output frequency in the first mode and setting the same carrier to an output frequency in the second mode; And an output unit that combines all the signals input in the first mode and transmits the combined signals to one antenna and transmits each signal input in the second mode through each of the plurality of antennas, And transmitting a signal having a bandwidth of an integer multiple of the predetermined bandwidth through an antenna, and the second mode is a mode of transmitting a signal of the predetermined bandwidth through multiple antennas.

According to another aspect of the present invention, a signal receiving apparatus divides a received signal input in a first mode into a predetermined bandwidth and inputs the signal into an analog RF block having a respective carrier frequency, An input unit for inputting each block; And a channel estimator for receiving a plurality of VHT-LTFs in the second mode and calculating four channel constants for each subcarrier through a combination of the plurality of received VHT-LTFs, And the second mode is a mode for receiving the signal of the predetermined bandwidth through the multiple antennas. The second mode is a mode for receiving the signal of the predetermined bandwidth through the multiple antennas.

According to another aspect of the present invention, a signal transmission method includes: operating as a segment parser in a first mode and operating as a stream parser in a second mode; Generating a temporal cyclic delay for each of the antennas so that signals transmitted from the antennas have different phase shifts in the second mode; (VHT-LTF) field including an OFDM (Orthogonal Frequency Division Multiplexing) symbol of a predetermined pattern in the first mode, and transmits a plurality of VHT-LTF fields ; Setting each carrier frequency of a predetermined bandwidth signal to an output frequency in the first mode and setting the same carrier to an output frequency in the second mode; The method of claim 1, further comprising transmitting all signals input in the first mode to a single antenna, and transmitting each signal input in the second mode through a plurality of antennas, And the second mode is a mode for transmitting the signal of the predetermined bandwidth through the multiple antennas. The second mode is a mode for transmitting a signal of the predetermined bandwidth through the multiple antennas.

According to another aspect of the present invention, a signal receiving method includes dividing a received signal input in a first mode into a predetermined bandwidth, inputting the received signal into an analog RF block having respective carrier frequencies, Inputting them into an analog RF block; And a channel estimation step of receiving a plurality of VHT-LTFs in the second mode and calculating four channel constants for each subcarrier through the combination of the plurality of received VHT-LTFs, A mode for receiving a signal of an integer multiple of the predetermined bandwidth through an antenna, and the second mode is a mode for receiving a signal of the predetermined bandwidth through multiple antennas.

According to the present invention, both a multi-antenna single-bandwidth mode and a single-antenna multi-bandwidth mode can be provided or provided through a single modem structure.

1 is an example of a system for transmitting a signal of a 160 MHz band using a single antenna to which the present invention is applied.
2 shows an example of the structure of a frame of an analog signal generated according to the present invention.
3 shows an example of a spectrum of an analog signal generated according to the present invention.
FIG. 4 illustrates an example of a structure of a transmitter that transmits two independent data streams in 80 MHz bandwidth using two transmit antennas according to the present invention.
5 shows an example of a frame structure of an 80 MHz bandwidth mode for transmitting two data streams according to the present invention.
6 shows an example of a signal spectrum in an 80 MHz bandwidth mode for transmitting two data streams in accordance with the present invention.
7 shows an example of a multi-antenna multi-bandwidth transmitting apparatus according to the present invention.
FIG. 8 shows an example of a multi-antenna multi-bandwidth receiving apparatus according to the present invention.
FIG. 9 is a block diagram schematically illustrating a single-bandwidth 2 * 2 MIMO mode and a multi-bandwidth 1 * 1 single-input single-output (SISO) mode in units of antennas and segments according to the present invention.
10 is a diagram illustrating channel constants of a channel estimation unit in a 2 * 2 MIMO mode using multiple antennas.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Also, in order to clearly illustrate the present invention in the drawings, portions not related to the present invention are omitted, and the same or similar reference numerals denote the same or similar components.

In the present invention, for convenience of description, a mode using one antenna in a mode using two antennas in an 80 MHz bandwidth mode, a mode using one antenna in a 160 MHz bandwidth mode (including a continuous 160 MHz bandwidth mode and a non-continuous 80 + 80 MHz bandwidth mode) As an example. However, the scope of the present invention is not limited thereto, and the present invention can be extended to a case where the bandwidth is changed or the number of antennas is changed. For example, an 80 MHz bandwidth can be expanded to four antenna modes or 160 MHz two antenna modes. In addition, the 80 MHz bandwidth and the 160 MHz bandwidth are only examples according to the present invention, and a transceiver that simultaneously supports various types of single antenna wideband mode and multiple antenna narrowband mode, such as 50 MHz bandwidth, 100 MHz bandwidth, 10 MHz bandwidth and 20 MHz bandwidth The present invention is equally applicable. Hereinafter, the first mode refers to a single antenna wideband mode, and the second mode refers to a multiple antenna narrowband mode.

1 is an example of a system for transmitting a signal of a 160 MHz band using a single antenna to which the present invention is applied. For example, it may be a transmitting device that transmits on a 160 MHz bandwidth (including both 160 MHz continuous bandwidth or two non-contiguous 80 MHz bandwidth transmissions) based on the IEEE 802.11ac standard.

Referring to FIG. 1, data transmitted from a MAC (Medium Access Control) layer is scrambled in a scrambler. In an encoder parser, FEC Forward Error Correction) Determines how many encoders to use and distributes the bits to each FEC encoder.

The data encoded in the FEC encoder is separated again in the stream & segment parser.

In this case, when the transmission is performed through a single antenna with a bandwidth of 160 MHz, the stream & segment parser functions only as a segment parser without a stream parser function. The data separated by each segment (here, the segment means each 80 MHz bandwidth) is interleaved in an interleaver, is statelatively mapped in a constellation mapper, is transmitted in a subcarrier allocation unit to an OFDM (Inverse Fast Fourier Transform) according to Orthogonal Frequency Division Multiplexing subcarrier allocation rules. An IFFT unit performs an IFFT to generate an OFDM symbol.

After a guard interval is added to the generated OFDM symbol and windowing is performed, a preamble defined in the preamble generation is added to the beginning of each packet, and interpolation and Filtering is performed and transferred to the DAC to be converted into an analog signal.

The analog signal thus constructed is up-converted to different center frequencies f0 and f1 divided by the same oscillator, and then the two signals are combined in a combiner to produce one Lt; / RTI >

If the up-converted analog signals at the different center frequencies do not go through the combiner, they can be transmitted through the two antennas.

2 shows an example of the structure of a frame of an analog signal generated according to the present invention. 160MHz bandwidth, frame structure when transmitting a single data stream

Referring to FIG. 2, a legacy-short training field (L-STF) is transmitted and a legacy-long field (L-LTF) SIG A, very high throughput-short training field (VHT-STF), very high throughput-long training field (VHT-LTF 1), data field and VHT-SIG B (very high throughput-signal field B). The order in which the fields are transmitted may be changed.

In L-STF, a promised signal with a period of 0.8usec can be transmitted for 8us, which is the length of two OFDM symbol periods, for initial signal detection, automatic gain control, approximate half-sine frequency error estimation, In L-LTF, a predetermined OFDM symbol for channel estimation required for accurate carrier frequency error estimation and L-SIG and VHT-SIG A demodulation is transmitted twice. In the L-SIG, the terminals of the IEEE 802.11ac standard demodulate to the extent that the frames are transmitted during the entire IEEE 802.11ac frame period. For the purpose of knowing that the frames are transmitted during the entire IEEE 802.11ac frame period, And the code rate or data rate information is not used for actual demodulation, it can be fixed to 6 Mb / s), and the length information (when calculating the total frame transmission time, not the length information of the corresponding frame, at a transmission rate of 6 Mb / s The corresponding length can be calculated and set) and the like are transmitted. In the VHT-SIG A, information about the transmission rate, bandwidth, partial AID (Partial Association ID), number of transport streams, guard interval length, beamforming, and the like for the frame receiving the frame (for example, IEEE 802.11ac terminal) Are transmitted during two OFDM symbols, and in VHT_STF, a predetermined signal pattern of 0.8usec period is transmitted for one OFDM symbol time (i.e., during 4usec) so as to newly perform automatic gain control in consideration of a change in the reception power of the frame , VHT_LTF 1 (the total number of OFDM symbols corresponding to VHT-LTF is variable according to the number of transmission data streams, and VHT-LTF 1 is the first OFDM symbol among them), VHT-SIG B and a channel In the data field, data transmitted from the real MAC is modulated according to the frame information in the VHT-SIG A so that a plurality of OFDM symbols are transmitted. In the case of multi-user MIMO in the VHT-SIG B, OFDM symbols including the length and rate information of each user are transmitted.

If only a single data stream is transmitted, only VHT-LTF1 corresponding to an OFDM symbol is transmitted. However, if the number of transport streams increases, the number of OFDM symbols constituting VHT-LTF also increases. That is, when only a single stream is transmitted, only VHT-LTF1 corresponding to one OFDM symbol is transmitted, and when N transport streams are transmitted, VHT-LTF1 to VHT- Lt; / RTI >

3 shows an example of a spectrum of an analog signal generated according to the present invention. And the spectrum of the transmission signal at the time of transmission of the 160 MHz bandwidth.

Referring to FIG. 3, when the bandwidth is 160 MHz, two transmission segments have f0 and f1, respectively, at a center frequency, and are transmitted in a spectrum of a bandwidth of 80 MHz at each center frequency.

FIG. 4 illustrates an example of a structure of a transmitter that transmits two independent data streams in 80 MHz bandwidth using two transmit antennas according to the present invention. And is an example of a structure of a transmission end specified in IEEE 802.11ac.

Referring to FIG. 4, two transmission data streams are transmitted, and a center frequency at which two streams are transmitted is equal to f0.

On the other hand, cyclic shift diversity (CSD) is applied to the second stream. Here, when a frame is transmitted using multiple antennas (for example, IEEE 802.11ac standard), a CSD makes a time-cyclic delay for each antenna and gives different phases to signals transmitted from the antennas. The stream & segment parser also functions as a stream parser. In addition, the structure of the preamble is adjusted to the 80MHz bandwidth, and two VHT-LTFs are transmitted to enable MIMO (Multiple Input Multiplex Output channel estimation).

5 shows an example of a frame structure of an 80 MHz bandwidth mode for transmitting two data streams according to the present invention. 80 MHz bandwidth, and a frame structure for transmitting two data streams.

Referring to FIG. 5, L-STF is transmitted first and L-LTF, L-SIG, VHT-STIG, VHT-STF, VHT-LTF1, VHT- -SIG B in this order.

Since there are two transport streams, the VHT-LTF 2 field is further included. Since the number of transmission data streams increases to two, it is necessary to estimate the channel from each transmission antenna to the reception antenna in order to detect it. Thus, VHT-LTF 2 is additionally transmitted along with VHT-LTF 1 to enable MIMO channel estimation. In the VHT-LTF2 field, a predetermined pattern corresponding to one OFMD symbol is transmitted. The pattern is the same as VHT-LTF1, and is transmitted in a structure in which only the sign is changed according to the antenna.

6 shows an example of a signal spectrum in an 80 MHz bandwidth mode for transmitting two data streams in accordance with the present invention. The spectrum of the transmission signal at the time of 80 MHz bandwidth transmission

Referring to FIG. 6, when the bandwidth is 80 MHz, two transmission segments have a center frequency of f0 and a center frequency of 80 MHz, respectively.

Now, a multi-antenna multi-band transceiver and a transmitting and receiving method according to the present invention will be described. Hereinafter, the transmitting apparatus or the receiving apparatus may be a modem.

7 shows an example of a multi-antenna multi-bandwidth transmitting apparatus according to the present invention. And a transmission terminal structure capable of supporting both a 160Mhz bandwidth mode (first mode) for transmitting a single data stream and an 80Mhz bandwidth mode (second mode) for transmitting two data streams.

7, a transmitting apparatus 700 includes a MAC 701, a scrambler 703, an encoding parser 705, FEC encoders 707 and 708, a stream and segment parser 711, interleavers 713 and 714, A GI window inserter 729 and 730, a preamble generator 733, an interpolation filtering unit 735 and 736, a phased locked loop (PLL), and a sub-carrier allocation unit 732. [ DACs 739 and 740, analog RF units 747 and 748, and an output unit 751.

The stream and the segment parser recognize themselves by inputting a separate input unit (not shown), or by the transmitting apparatus itself, and convert the mode into one of the first mode or the second mode. When the first mode is converted, the transmission is performed through a single antenna with a bandwidth of 160 MHz, so that it functions only as a segment parser without a stream parser function. When the second mode is switched, the stream & segment parser functions as a stream parser since the stream is transmitted through a multiple antenna through a bandwidth of 80 MHz.

The CSD operates only when it is converted into the second mode.

The preamble generator transmits a preamble. When the mode is switched to the first mode, only one VHT-LTF is transmitted. The preamble generator transmits two VHT-LTFs (VHT-LTF1 and VHT-LTF2) when converted into the second mode. Two antennas are used to transmit two streams. Since two channels from the two transmit antennas to the receive antenna, that is, two channels, must be estimated, two VHT-LTFs are transmitted and the channel can be estimated.

The PLL sets the PLL output frequency to each carrier frequency of the 80 MHz bandwidth signal in a first mode that supports multiple bandwidths. The PLL sets the two PLL output frequencies to the same carrier frequency in a second mode that supports a single bandwidth and multiple antennas.

In the first mode, the output unit combines the two signals and transmits them to one antenna. At this time, the antenna unit includes only one antenna, or only one of the plurality of antennas operates. The output unit transmits the two signals to the two antennas in the second mode. At this time, the antenna unit includes at least two antennas.

The multi-antenna multi-bandwidth transmitting apparatus according to the present invention can accommodate both the multi-antenna single-bandwidth mode and the single-antenna multi-bandwidth mode

FIG. 8 shows an example of a multi-antenna multi-bandwidth receiving apparatus according to the present invention. And a receiving terminal structure capable of supporting both a 160Mhz bandwidth mode (first mode) for receiving a single data stream and an 80Mhz bandwidth mode (second mode) for receiving two data streams. The receiving apparatus performs an inverse process of the transmitting apparatus.

8, the receiving apparatus 800 includes an input unit 801, analog RFs 803 and 804, ADCs 811 and 812, PLLs 807 and 808, decimation filtering 815 and 816, a digital front end 819 and 820, A channel estimator 831, a subcarrier segmentation 833,834, a detector 837, a deinterleaver 839 and 840, a stream and segment parser 843, an FEC decoder 845 and 846, a decoding parser 823 and 844, 849, a descrambler 851, and a MAC 853.

If the number of antennas is determined according to a mode that the terminal desires to support, one or two antennas are installed before the input unit.

If a multi-bandwidth signal is received through one antenna, the received signal is divided into two and input to an analog RF block with each carrier frequency. If a single bandwidth signal is received through two antennas, the received signal is input to two analog RF blocks.

The baseband analog signal passed from the analog RF block to the ADC is converted to a digital signal through the ADC.

Then, a desired signal is extracted through decimation filtering, and packet detection and frequency time synchronization are performed in the digital front end block.

The signal with the guard interval removed through the GI deletion is input to the FFT and converted into a frequency domain signal. In the channel estimation unit, channel estimation is performed using the LTF, and MIMO detection is performed in the detector block. In the subcarrier division part, it is divided into subcarriers as necessary. Some of the total subcarriers in the FFT process are null carriers that are not used, some are pilot carriers that are predetermined for phase and timing tracking, Data carrier with data, wherein the subcarrier dividing unit separates the subcarrier into one or more of a null carrier, a pilot carrier, or a data carrier.

The detected signal is demodulated through a deinterleaver, a stream and segment parser, an FEC decoder, a descrambler, and then delivered to the MAC.

The channel estimator and detector block are particularly distinguished from the conventional one for receiving a multi-bandwidth single stream and receiving a single bandwidth multi-stream in a receiving apparatus, and a case of receiving a single bandwidth multi-stream may be designed to include a case of a multi- have.

FIG. 9 is a block diagram schematically illustrating a single-bandwidth 2 * 2 MIMO mode and a multi-bandwidth 1 * 1 single-input single-output (SISO) mode in units of antennas and segments according to the present invention. Here, the 2 * 2 MIMO mode means a multi-input multi-output mode in which two data streams are transmitted and received using two transmission antennas and two reception antennas. On the other hand, the 1 * 1 SISO mode means a single input single output mode in which one data stream is transmitted and received using one transmission antenna and one reception antenna.

9, four channels are formed in the 2 * 2 MIMO mode, but only two channels exist between the segments in the 1 * 1 SISO mode (b). Therefore, a 2 * 2 MIMO mode using multiple antennas is a general structure including a 1 * 1 SISO mode.

If the channel estimation and detector of FIG. 8 is designed to support a 2 * 2 MIMO mode using multiple antennas, a 1 * 1 SISO mode can also be supported using some of the channels.

In a 2 * 2 MIMO mode using multiple antennas, a channel estimator receives two VHT-LTFs (VHT-LTF1 and VHT-LTF2) and generates four channel constants for each subcarrier through a combination of received VHT- H11, H12, H21, and H22 are calculated. Here, Hij denotes a channel constant between the j-th transmission antenna (or segment) and the i-th reception antenna (or segment).

10 is a diagram illustrating channel constants of a channel estimation unit in a 2 * 2 MIMO mode using multiple antennas.

Referring to FIG. 10, since only two channels are used in a 1 * 1 SISO mode using a single antenna, H12 and H21 can be designed as a zero matrix (b).

At this time, the channel estimation unit (a) supporting 2 * 2 MIMO also supports 1 * 1 SISO mode. Likewise, a detector supporting a 2 * 2 MIMO mode can perform multi-bandwidth detection in a 1 * 1 SISO mode.

According to the present invention, it is possible to selectively support the 80 MHz bandwidth mode and the 160 MHz bandwidth mode by changing the channel constants of the channel estimation unit and the detector using the same transceiver. Therefore, it is possible to implement both modes in one transceiver according to the characteristics of the terminal and the application service.

In the above-described exemplary system, the methods are described on the basis of a flowchart as a series of steps or blocks, but the present invention is not limited to the order of the steps, and some steps may occur in different orders . It will also be understood by those skilled in the art that the steps shown in the flowchart are not exclusive and that other steps may be included or that one or more steps in the flowchart may be deleted without affecting the scope of the invention.

Claims (16)

In the signal transmission apparatus,
A parser operating as a segment parser without the function of the stream parser in the first mode and operating as a stream parser without the function of the segment parser in the second mode;
A cyclic shift diversity (CSD) generating a temporal cyclic delay for each of the antennas so that signals transmitted from the respective antennas have different phase shifts in the second mode;
(VHT-LTF) field including an OFDM (Orthogonal Frequency Division Multiplexing) symbol of a predetermined pattern in the first mode, and transmits a plurality of VHT-LTF fields A preamble generator for transmitting the preamble;
A phase locked loop (PLL) for setting a plurality of different carrier frequencies in the first mode to an output frequency and setting a single carrier frequency to an output frequency in the second mode; And
And an output unit that combines all the signals input in the first mode and transmits the combined signals to one antenna and transmits each signal input in the second mode in each of the plurality of antennas,
The first mode is a mode for transmitting a multi-bandwidth signal through a single antenna, the second mode is a mode for transmitting a single-bandwidth signal through multiple antennas,
Wherein the size of the multiple bandwidth is an integer multiple of the size of the single bandwidth,
Wherein the number of VHT-LTF fields is variably determined based on the number of streams, and the number of the plurality of VHT-LTF fields increases as the number of streams increases.
Signal transmission device. The method according to claim 1,
Characterized in that the single bandwidth is 80 MHz and the multiple antennas are two antennas. The method according to claim 1,
Further comprising an input unit for selectively inputting one of the first mode and the second mode. The method according to claim 1,
Further comprising an analog RF (Radio Frequency) unit for inputting an analog signal to the output unit based on the frequency set in the PLL. A signal receiving apparatus comprising:
An input unit for inputting a signal received in the first mode into a plurality of analog RF blocks having a plurality of different carrier frequencies and inputting a signal received in the second mode to the plurality of analog RF blocks; And
And a channel estimator for receiving the plurality of VHT-LTFs in the second mode and calculating four channel constants for each subcarrier through the combination of the plurality of received VHT-LTFs,
The first mode is a mode for receiving a multi-bandwidth signal through a single antenna, the second mode is a mode for receiving a single-bandwidth signal through multiple antennas,
Wherein the size of the multiple bandwidth is an integer multiple of the size of the single bandwidth,
The number of VHT-LTF fields is variably determined based on the number of streams, and as the number of streams increases, the number of VHT-LTF fields increases,
Signal receiving device. 6. The method of claim 5,
In the first mode,
Wherein the channel estimator sets a part of the four channel constants as a zero matrix. 6. The method of claim 5,
Characterized in that the single bandwidth is 80 MHz and the multiple antennas are two antennas. 6. The method of claim 5,
Further comprising an input unit for selectively inputting one of the first mode and the second mode. In the signal transmission method,
A parsing step of operating in a first mode as a segment parser without the function of a stream parser and in a second mode as a stream parser without the function of a segment parser;
Generating a temporal cyclic delay for each of the antennas so that signals transmitted from the antennas have different phase shifts in the second mode;
(VHT-LTF) field including an OFDM (Orthogonal Frequency Division Multiplexing) symbol of a predetermined pattern in the first mode, and transmits a plurality of VHT-LTF fields ;
Setting a plurality of different carrier frequencies in the first mode to an output frequency and setting a single carrier frequency to an output frequency in the second mode;
Transmitting all the signals input in the first mode to a single antenna by combining the signals and transmitting each signal input in the second mode through each of the plurality of antennas,
The first mode is a mode for transmitting a multi-bandwidth signal through a single antenna, the second mode is a mode for transmitting a single-bandwidth signal through multiple antennas,
Wherein the size of the multiple bandwidth is an integer multiple of the size of the single bandwidth,
Wherein the number of VHT-LTF fields is variably determined based on the number of streams, and the number of the plurality of VHT-LTF fields increases as the number of streams increases.
/ RTI > 10. The method of claim 9,
Wherein the single bandwidth is 80 MHz and the multiple antennas are two antennas. 10. The method of claim 9,
Further comprising the step of inputting one of the first mode and the second mode. 10. The method of claim 9,
And selectively inputting an analog signal based on the set frequency. In the signal receiving method,
Inputting a signal received in the first mode into a plurality of analog RF blocks having a plurality of different carrier frequencies and inputting a signal received in the second mode to each of the plurality of analog RF blocks; And
And a channel estimation step of receiving a plurality of VHT-LTFs in the second mode and calculating four channel constants for each subcarrier through a combination of the plurality of VHT-LTFs received,
The first mode is a mode for receiving a multi-bandwidth signal through a single antenna, the second mode is a mode for receiving a single-bandwidth signal through multiple antennas,
Wherein the size of the multiple bandwidth is an integer multiple of the size of the single bandwidth,
The number of VHT-LTF fields is variably determined based on the number of streams, and as the number of streams increases, the number of VHT-LTF fields increases,
Signal receiving method. 14. The method of claim 13,
In the first mode,
Wherein the channel estimating step estimates a channel by setting a part of the four channel constants as a zero matrix. 14. The method of claim 13,
Wherein the single bandwidth is 80 MHz and the multiple antennas are two antennas. 14. The method of claim 13,
Further comprising the step of selectively inputting one of the first mode or the second mode.

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