KR102194602B1 - Method for Implementing Multiple-Input and Multiple-Output(MIMO) Wireless Communication through Multi-antenna System - Google Patents

Abstract

The present invention relates to a method of implementing multiple input multiple output (MIMO) wireless communication through a multi-antenna system. More particularly, the present invention relates to a method of implementing MIMO wireless communication which can show high communication efficiency while being compatible with conventional signal input single output (SISO) wireless communication.

Description

Method for Implementing Multiple-Input and Multiple-Output (MIMO) Wireless Communication through Multi-antenna System}

The present invention relates to a method of implementing multiple input-multiple output (MIMO) wireless communication through a multi-antenna system, and more particularly, high communication efficiency while being compatible with conventional single input-single output (SISO) wireless communication. The present invention relates to a method of implementing multiple input-multiple output (MIMO) wireless communication.

Recently, mobile communication, WLAN (Wireless Local Area Network), digital broadcasting and satellite communication, as well as mobile communication systems such as 3GPP LTE/LTE-A and NR, and WAVE-based DSRC system, the leading player of V2X, are the demand for wireless services. Is increasing rapidly. With the development of such a new wireless transmission technology and the advent of wireless communication services, various information delivery and quality are required.

In addition, as cameras are installed in automobiles and Telematics is integrated, a wireless interface is applied to digital devices in the vehicle to wirelessly transmit HDTV (High Definition Television) quality video, and to exchange video and audio contents with portable devices. The technology is expected to be commercialized in the automotive industry. As a wireless interface technology that implements this, the IEEE 802.11 wireless LAN system, a WAVE system based on it, and even a 3GPP mobile communication network will be used in the automotive industry.

IEEE 802.11ax is a next-generation WLAN standard, applying MIMO (Multiple Input Multiple Output) antenna technology capable of spatial multiplexing, and is known as a promising technology in the field of wireless networks because it enables long-distance access up to several hundred meters.

The maximum transmission speed of this new wireless communication system technology has exceeded several hundred Mbps and has already reached the Gbps level, and a higher transmission technology is required for next-generation communication capable of various multimedia transmission of various devices in the future. To this end, it is necessary to incorporate the spatial multiplexing antenna technology of MIMO, which is currently adopted in many wireless standards, to the existing wireless communication technology.

An object of the present invention is to provide a method of implementing a multiple input-multiple output (MIMO) wireless communication capable of showing high communication efficiency while being compatible with a conventional single input-single output (SISO) wireless communication.

In order to solve the above problems, the present invention is a method of implementing multiple input-multiple output (MIMO) wireless communication through a multiple antenna system including N transmission antennas and M reception antennas, and transmit data by a demultiplexer. A demultiplexing step of demultiplexing and distributing N data; A data encoding step in which the N pieces of data distributed by the data encoding unit are OFDM-coded, respectively; A stream rotating step of matching the transmission data encoded by the stream rotator to the N transmission antennas; A transmission data processing step of performing processing for transmission through each transmission antenna by the transmission data processing unit; A carrier synthesis step of synthesizing a time-frequency code by a carrier synthesizer; And a data transmission step of transmitting transmission data through each transmission antenna. Including, the data transmitted through the transmission antenna, Short Training Field; Long Training Field; SIGNAL Field; Pilot-Long Training Field; And it provides a method for implementing a multiple input-multiple output wireless communication, including a data field.

In the present invention, the data encoding step includes a scrambling step of scrambling data bits; A convolution encoding step of block-coding data; A puncturing step of adjusting a transmission rate of block-coded data; An interleaving step of rearranging the order of the data sequence in a predetermined unit; And a mapping step of mapping the signal. Including, in the scrambling step, only data bits of PSDU may be scrambled.

In the present invention, the transmission data processing step includes: an inverse fast Fourier transform step of generating an antenna transmission signal for transmission through an antenna through an inverse Fourier transform; And a digital-analog conversion step of converting the generated antenna transmission signal into an analog signal. It may include.

In the present invention, N is 2, M is 2, and the Pilot-Long Training Field may generate two Pilot symbols.

In the present invention, the Pilot-Long Training Field may have 53 subcarriers as follows, and may generate a pilot bit by multiplying a preset mapping matrix by the subcarriers.

In the present invention, the SIGNAL Field is a 3-bit RATE; 3-bit MIMO Type; 12-bit LENGTH; And 6-bit SIGNAL TAIL; It may include.

In the present invention, N is 2, M is 2, and the MIMO Type is the number of antennas; Whether in MIMO Mode; And whether space-time coding; May contain information about.

According to an embodiment of the present invention, a signal can be efficiently transmitted through a multi-antenna system including a plurality of transmission antennas and a plurality of reception antennas.

According to an embodiment of the present invention, a signal can be efficiently transmitted by taking a spatial diversity gain and a spatial multiplexing gain through a multi-antenna system.

According to an embodiment of the present invention, a signal is transmitted without a significant change in the structure of a SIGNAL field in the MIMO mode and the SISO mode, thereby improving compatibility with the existing SISO mode.

1 is a diagram schematically showing a multi-antenna system according to an embodiment of the present invention.
2 is a diagram schematically illustrating a transmitter of a multi-antenna system according to an embodiment of the present invention.
3 is a diagram schematically illustrating an internal signal processing process of a data encoding unit according to an embodiment of the present invention.
4 is a diagram schematically showing an internal signal processing process of a transmission data processing unit according to an embodiment of the present invention.
5 is a diagram schematically illustrating a receiver of a multi-antenna system according to an embodiment of the present invention.
6 is a diagram schematically illustrating an internal signal processing process of a reception data processor according to an embodiment of the present invention.
7 is a diagram schematically showing an internal signal processing process of a data decoding unit according to an embodiment of the present invention.
8 is a diagram schematically showing the structure of transmission data according to an embodiment of the present invention.
9 is a diagram schematically showing the structure of transmission data according to an embodiment of the present invention.
10 is a diagram schematically showing the structure of a SIGNAL field of transmission data according to an embodiment of the present invention.

In the following, various embodiments and/or aspects are now disclosed with reference to the drawings. In the following description, for purposes of explanation, a number of specific details are disclosed to aid in an overall understanding of one or more aspects. However, it will also be appreciated by those of ordinary skill in the art that this aspect(s) may be practiced without these specific details. The following description and the annexed drawings set forth in detail certain illustrative aspects of one or more aspects. However, these aspects are exemplary and some of the various methods in the principles of the various aspects may be used, and the descriptions described are intended to include all such aspects and their equivalents.

Further, various aspects and features will be presented by a system that may include multiple devices, components and/or modules, and the like. It is also noted that various systems may include additional devices, components and/or modules, and/or may not include all of the devices, components, modules, etc. discussed in connection with the figures. It must be understood and recognized.

As used herein, “an embodiment,” “example,” “aspect,” “example,” and the like may not be construed as having any aspect or design described as being better or advantageous than other aspects or designs. . The terms'~part','component','module','system', and'interface' used below generally mean a computer-related entity, for example, hardware, hardware It can mean a combination of software and software, or software.

In addition, the terms "comprising" and/or "comprising" mean that the corresponding feature and/or element is present, but excludes the presence or addition of one or more other features, elements, and/or groups thereof. It should be understood as not.

In addition, terms including ordinal numbers such as first and second may be used to describe various elements, but the elements are not limited by the terms. These terms are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. The term and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

In addition, in the embodiments of the present invention, unless otherwise defined, all terms used herein including technical or scientific terms are commonly understood by those of ordinary skill in the art to which the present invention belongs. It has the same meaning as. Terms as defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the embodiments of the present invention, an ideal or excessively formal meaning Is not interpreted as.

1 is a diagram schematically showing a multi-antenna system according to an embodiment of the present invention.

Referring to FIG. 1, it can be seen that a multi-antenna system according to an embodiment of the present invention performs communication between N transmit antennas and M receive antennas through a MIMO channel.

In a multi-antenna system according to an embodiment of the present invention, MIMO-OFDM communication can be performed.

The OFDM scheme is a type of multi-carrier transmission using multiple carriers, and the transmission period in each channel increases by the number of carriers. In this case, since the frequency selective channel that appears during wideband transmission is approximated to a frequency non-selective channel without inter-symbol interference, compensation can be performed with a simple single tap equalizer.

In the diversity method, when a single transmit/receive antenna is used because the slope of the bit reception error rate (BER) curve is proportional to the signal-to-noise ratio of the diversity gain power SNR-d (d: diversity gain) under Rayleigh fading environment. The advantage is that transmission reliability can be improved. However, since the capacity cannot be increased in proportion to the number of antennas, it is difficult to obtain high frequency efficiency required in the next generation wireless communication system.

Unlike this, the spatial multiplexing scheme increases a transmission rate by transmitting different signals to independent subchannels provided by a multi-antenna environment. The number of different signals that can be simultaneously transmitted through multiple transmit antennas is equal to the minimum number of transmit/receive antennas used. Therefore, in order to sufficiently obtain the advantages of the spatial multiplexing scheme, unlike the diversity scheme, multiple antennas must be used at the transmit/receive end as many as the number of subchannels to be created at both the transmit/receive end.

Technologies applied to a multiple-input multiple-output (MIMO) system are classified into two technology groups, a diversity series and a multiplexing series, as described above.

The diversity scheme is a technology that improves reception performance by complementing channel deeps between paths by combining signals that have undergone different Rayleigh fading for each antenna by a plurality of transmit/receive antennas. Therefore, its performance is determined by the number of independent channels, and this is expressed as diversity gain. Diversity technology is divided into transmit diversity and receive diversity according to whether the diversity gain is obtained at the transmitting end or the receiving end. When the number of transmit antennas is N and there are M receive antennas, the maximum diversity gain is MN because up to MN independent fading channels can be combined. The multiplexing method is a method of increasing the transmission speed by creating virtual sub-channels between the transmitting/receiving antennas and transmitting different data through each transmitting antenna. Unlike the diversity method, the multiplexing method cannot sufficiently obtain the gain when multiple antennas are used only at the transmitting end or the receiving end.

The performance of the multiplexing scheme is expressed by the number of independent transmission signals that can be transmitted simultaneously as a multiplexing gain, which is equal to the minimum number of antennas at the transmitting end and the number of antennas at the receiving end.

The gains that can be obtained through the diversity method and the multiplexing method are in a trade off relationship with each other, and therefore, it is decided which method to apply depending on the conditions of the communication environment or the user's request.

2 is a diagram schematically illustrating a transmitter of a multi-antenna system according to an embodiment of the present invention.

Referring to FIG. 2, a detailed configuration of a transmitter of a multi-antenna system according to an embodiment of the present invention can be confirmed. 2 shows a transmission unit of a multi-antenna system including two transmission antennas.

In a spatial multiplexed MIMO multi-antenna system, there are three types of methods according to a method of combining a channel encoder and an antenna.

First, the horizontal coding method requires a channel encoder equal to the number of transmit antennas. Although the order of diversity gain is the same as the number of receiving antennas, the transmission rate can be controlled for each antenna, and the structure of the receiving end is simple.

Second, in the vertical coding scheme, first, a single channel encoder is used for all data, and the output thereof is demuxed to transmit different data for each antenna. Unlike the horizontal coding scheme, this scheme has the advantage of requiring one encoder, but has a disadvantage in that the data processing speed increases in proportion to the number of antennas when implemented. However, it is possible to obtain a diversity gain of the product of the number of transmit antennas and the number of receive antennas.

Third, the diagonal coding scheme is similar to the horizontal coding scheme, but a layer rotator is added before transmission to the transmit antenna. The data layers from each encoder are transmitted while being rotated through the layer rotator over time. The diversity gain order of the diagonal coding scheme can be expressed as a product of the number of transmit/receive antennas such as the vertical coding scheme.

Referring to FIG. 2, it can be seen that the transmitter of the multi-antenna system according to an embodiment of the present invention is based on a diagonal coding scheme. As shown in FIG. 2, the transmission unit according to an embodiment of the present invention is compatible with the existing SISO-OFDM system, and the implementation complexity of each channel encoder is the same as before.

As shown in FIG. 2, according to an embodiment of the present invention, a demultiplexing step of demultiplexing transmission data by a demultiplexer and distributing it into N pieces of data; A data encoding step in which the N pieces of data distributed by the data encoding unit are OFDM-coded, respectively; A stream rotating step of matching the transmission data encoded by the stream rotator to the N transmission antennas; A transmission data processing step of performing processing for transmission through each transmission antenna by the transmission data processing unit; A carrier synthesis step of synthesizing a time-frequency code by a carrier synthesizer; And a data transmission step of transmitting transmission data through each transmission antenna. Wireless communication can be implemented through a data transmission method including.

3 is a diagram schematically illustrating an internal signal processing process of a data encoding unit according to an embodiment of the present invention.

Referring to FIG. 3, the data encoder may process a signal through sequentially through a Scrambler, a convolutional encoder, a Puncturer, a bit interleaver, and a constellation mapper.

The scrambler scrambles data bits using a Pseudo Random Binary Sequence (PRBS) player. The preamble and PHY header are not scrambled and are used only in PSDU.

The convolutional encoder is one of channel coding methods that add redundancy to make it robust against channel errors. In a multi-antenna system according to an embodiment of the present invention, a convolutional encoder having a confinement length of 7 and a 1/2 or 1/3 ratio may be used, and various transmission rates may be provided while changing the puncturing ratio.

Bits on which convolutional encoding has been performed may have various data rates through various puncturing methods. Puncturing removes part of the transmitted data bit and transmits it, and restores the data in the decoder by filling the dummy bit in the removed bit part at the receiving end.

The bit interleaver is placed after the puncturer. Bit interleaver is a technology that rearranges the order of data columns into a certain unit (such as columns and rows of blocks), so that even if a bit in the middle of a data column is lost due to instantaneous noise, its effect is localized to recover it. This is done to make it strong against burst errors, and a frequency diversity gain can be obtained.

The multi-antenna system according to an embodiment of the present invention uses the constellation of QPSK for each subcarrier at a low transmission rate, and when a higher transmission rate, i.e., a high transmission rate, is required, a modulation scheme up to 16-QAM and 64-QAM is used in stages. You can use it by raising it.

In an embodiment of the present invention, an Alamouti technique may be used as an encoding method. In the 2x2 MIMO mode according to an embodiment of the present invention, it may be encoded as shown in the following equation.

In the above equation, the vertical axis represents the antenna axis, and column 1 represents antenna 0 and column 2 represents the output of antenna 1. On the other hand, the horizontal axis is the frequency axis and represents the even and odd subcarriers. X is a transmission signal of two subcarriers, and a subscript indicates an even-odd among the values of the two subcarriers.

4 is a diagram schematically showing an internal signal processing process of a transmission data processing unit according to an embodiment of the present invention.

Referring to FIG. 4, in the transmission data processing unit, a signal may be processed through an IFFT and a DAC in sequence.

The IFFT is an inverse fast Fourier transform unit, and generates a signal as an OFDM signal for transmission to an antenna through an inverse fast Fourier transform.

In the DAC, the digital signal of the IFFT can be converted through a digital to analog converter (DAC) to apply a signal to the antenna.

5 is a diagram schematically illustrating a receiver of a multi-antenna system according to an embodiment of the present invention.

5 shows a receiving unit corresponding to the transmitting unit of the multi-antenna system as described above. The transmitting unit of the multi-antenna system according to an embodiment of the present invention is transmitted to the existing SISO-OFDM system in a spatial multiplexing method. A MIMO-OFDM decoder and a layer rotator are added to recover the signal. The MIMO-OFDM decoder removes the channel effect from the signal received through the MIMO channel, and the layer rotator rotates the decoded received signal according to time.

To examine the structure of the MIMO receiver, first, a general MIMO transmission/reception system is assumed. Assuming a system using M antennas at the transmitting end and N antennas at the receiving end, the received signal Y(k) of the k-th subcarrier having the number of K subcarriers is as follows.

In the OFDM-based system, when the maximum time delay of the multipath is less than the periodic extension period of OFDM, inter-symbol interference does not occur, and thus the transmission signal can be restored without loss even when signal processing is performed in the frequency domain.

If the above equation is expressed as a transmission equivalent matrix, it can be expressed as the following equation.

In the above equation, k represents a subcarrier of OFDM and has a value of 0≤k≤K-1.

6 is a diagram schematically illustrating an internal signal processing process of a reception data processor according to an embodiment of the present invention.

Referring to FIG. 6, the reception data processing unit may sequentially process signals through LNA, LPF, VGA, ADC, Synchronization and FFT.

LNA is a low noise amplifier designed to minimize noise while amplifying a weak RF signal received through an antenna. A signal received through the receiving antenna is amplified through such an LNA to generate a signal that is easy to be processed by the receiver circuit.

The LPF is a low pass filter and passes only low frequency components below a preset reference. High-frequency noise is removed through such LPF.

VGA is a variable gain amplifier that can amplify a signal while removing interference outside a desired band. Since it is difficult to sufficiently amplify the received signal with only the aforementioned LNA, it can be amplified through VGA.

ADC is an analog to digital converter that converts a continuous analog signal into a binary digital signal through sampling, quantization, and encoding.

After that, the signal is synchronized and converted into an OFDM signal that can be demodulated through Fast Fourier Conversion.

7 is a diagram schematically illustrating an internal signal processing process of a data decoding unit according to an embodiment of the present invention.

Referring to FIG. 7, signal processing is performed in the reverse order of signal processing performed by the transmitter of the multi-antenna system described above.

Referring to FIG. 7, the data decoder may sequentially process a signal through DCM demapping, Deinterleaver, Depuncturer, Viterbi decoder, and Descrambler.

This is the reverse order of signal processing by the data encoder described in FIG. 3, and data may be decoded by performing the above-described process in FIG. 3 in the reverse order.

Demapping the signal through DCM demapping, rearranging the order of the rearranged data columns back to the original order through the deinterleaver, filling dummy bits in the bits removed through the depuncturer, restoring data through the Viterbi decoder, and descrambler To restore the scrambled data bits.

8 and 9 are diagrams schematically showing the structure of transmission data according to an embodiment of the present invention.

8 and 9 illustrate the structure of transmission data transmitted through the multi-antenna system. FIG. 9 shows a more schematic configuration, and FIG. 8 illustrates the configuration disclosed in FIG. 9 in more detail.

In the data transmitted through the transmission antenna, the data structure in the SISO mode and the MIMO mode is changed. 8 and 9, it can be seen that the SISO Mode has the same data structure as the IEEE 802.11p physical layer standard.

Meanwhile, data transmitted through the transmission antenna in the MIMO mode according to an embodiment of the present invention may include: Short Training Field; Long Training Field; SIGNAL Field; Pilot-Long Training Field; And a Data Field. This is a Pilot-Long Training Field that includes two Pilot symbols in front of the Data Field when compared to the SISO Mode; It can be seen that it further includes.

In this way, since the transmission data includes a Short Training Field, a Long Training Field, and a Pilot-Long Training Field, synchronization and channel estimation of the OFDM physical layer can be performed. Such data is composed of a preset symbol signal, and communication is performed through the symbol signal.

The Short Training Field detects the start of a frame, estimates the approximate frequency deviation, and enables fine time synchronization.

Long Training Field and Pilot-Long Training Field allow you to estimate channels and estimate fine frequency deviations.

Meanwhile, in a multi-antenna system including two transmission antennas and two reception antennas, the Pilot-Long Training Field according to an embodiment of the present invention may generate two pilot symbols. In this case, the pilot symbol may be arranged in consideration of a coherence bandwidth of a channel, a coherence time, and a reduction in bandwidth efficiency according to the use of a pilot tone.

The Pilot-Long Training Field may have 53 subcarriers as follows.

In the present invention, a pilot bit may be generated by multiplying a preset mapping matrix by the subcarrier. An example of such a mapping matrix is as follows.

In the present invention, a channel is estimated using such a pilot symbol.

10 is a diagram schematically showing the structure of a SIGNAL field of transmission data according to an embodiment of the present invention.

10 shows the structure of the SIGNAL Field in SISO Mode and MIMO Mode. The SIGNAL Field of SISO Mode follows a conventional standard, and the SIGNAL Field of MIMO Mode that can be used in a multi-antenna system according to an embodiment of the present invention is composed of 24 bits, and may have the same size as the conventional IEEE 802.11p standard. . In this way, by using a SIGNAL field of the same size as the standard SISO Mode, the method of implementing wireless communication according to an embodiment of the present invention can exhibit high compatibility.

The SIGNAL field contains information on the transmission rate to be used in the DATA field and the packet length to be transmitted.

Referring to FIG. 10, in an embodiment of the present invention, the SIGNAL Field in MIMO Mode includes a 3-bit RATE; 3-bit MIMO Type; 12-bit LENGTH; And 6-bit SIGNAL TAIL; It may include.

Compared with the SISO mode of FIG. 10, the SIGNAL field of the MIMO mode according to an embodiment of the present invention includes one small number of RATE bits, no reserved bits and no parity bits, but includes a 3-bit MIMO type bit.

More specifically, in order, bits 0 to 2 may be allocated as RATE, bits 3 to 4 may be MIMO Type, bits 5 to 16 may be LENGTH, bit 17 may be MIMO Type, and bits 18 to 23 may be assigned as Tail bits.

Table 1 below shows the transmission rate according to the RATE bit according to an embodiment of the present invention. In the IEEE 802.11p standard, 4 bits are used to indicate the transmission rate, but in an embodiment of the present invention, the transmission rate may be indicated using 3 bits. In this way, information of the MIMO mode can be transmitted by reducing the number of RATE bits by one and using it as a MIMO type.

SISO Mode(R1-R4) MIMO Mode(R1-R3) Rate(Mb/s 10MHz channel spacing) 1101 110 3 1111 111 4.5 0101 010 6 0111 011 9 1001 100 12 1011 101 18 0001 000 24 0011 001 27

Meanwhile, in an embodiment of the present invention, the MIMO Type includes: the number of antennas; Whether in MIMO Mode; And whether space-time coding; May contain information about.

In the 2x2 MIMO multi-antenna system as in the embodiment of the present invention, the first bit (T1) of the MIMO type shown in FIG. 10 may represent the number of antennas. For example, if the first bit is 0, it may indicate that there are two antennas, and if the first bit is 1, it may indicate that there are one antenna.

Meanwhile, the second bit (T2) of the MIMO type may indicate whether the MIMO mode is present. For example, when the second bit is 0, it may represent the SISO mode, and when the second bit is 1, it may represent the MIMO mode.

Meanwhile, the third bit (T3) of the MIMO type may indicate whether space-time coding is performed. For example, when the third bit is 0, it may represent space-time coding (STC), and when the third bit is 1, it may represent spatial multiplexing (SM).

According to an embodiment of the present invention, a signal can be efficiently transmitted through a multi-antenna system including a plurality of transmission antennas and a plurality of reception antennas.

According to an embodiment of the present invention, a signal can be efficiently transmitted by taking a spatial diversity gain and a spatial multiplexing gain through a multi-antenna system.

According to an embodiment of the present invention, a signal is transmitted without a significant change in the structure of a SIGNAL field in the MIMO mode and the SISO mode, thereby improving compatibility with the existing SISO mode.

As described above, although the embodiments have been described by the limited embodiments and drawings, various modifications and variations are possible from the above description by those of ordinary skill in the art. For example, the described techniques are performed in a different order from the described method, and/or components such as a system, structure, device, circuit, etc. described are combined or combined in a form different from the described method, or other components Alternatively, even if substituted or substituted by an equivalent, an appropriate result can be achieved. Therefore, other implementations, other embodiments, and claims and equivalents fall within the scope of the claims to be described later.

Claims (7)

A method of implementing multiple input-multiple output (MIMO) wireless communication through a multi-antenna system including N transmit antennas and M receive antennas,
A demultiplexing step of demultiplexing transmission data by a demultiplexer and distributing it to N data pieces;
A data encoding step in which the N pieces of data distributed by the data encoding unit are OFDM-coded, respectively;
A stream rotating step of matching the transmission data encoded by the stream rotator to the N transmission antennas;
A transmission data processing step of performing processing for transmission through each transmission antenna by the transmission data processing unit;
A carrier synthesis step of synthesizing a time-frequency code by a carrier synthesizer; And
A data transmission step of transmitting transmission data through each transmission antenna; Including,
Data transmitted through the transmission antenna,
Short Training Field; Long Training Field; SIGNAL Field; Pilot-Long Training Field; And a Data Field,
The SIGNAL Field,
3-bit RATE;
3-bit MIMO Type;
12-bit LENGTH; And
6-bit SIGNAL TAIL; Including a multi-input-multiple output method for implementing wireless communication.
delete The method according to claim 1,
The transmission data processing step,
An inverse fast Fourier transform step of generating an antenna transmission signal for transmission through an antenna through an inverse Fourier transform; And
A digital-analog conversion step of converting the generated antenna transmission signal into an analog signal; Including a multi-input-multiple output method for implementing wireless communication.
The method according to claim 1,
The N is 2, the M is 2,
The Pilot-Long Training Field,
A method of implementing a multi-input-multi-output wireless communication that generates two pilot symbols.
delete delete The method according to claim 1,
The N is 2, the M is 2,
The MIMO Type,
Number of antennas;
Whether in MIMO Mode; And
Space-time coding; A method of implementing a multiple input-multiple output wireless communication, including information on.

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