KR100745140B1 - MIMO System using Hybrid ARQ Method and the Retransmission Method thereof - Google Patents

Abstract

The present invention relates to a multi-antenna transceiver and a retransmission method thereof for performing hybrid automatic retransmission.

To this end, the present invention encodes and transmits the initial transmission signal transmitted to the receiving apparatus in the form of an initial transmission matrix, which is a linear distributed code, and receives an error check result for the initial transmission signal from the receiving apparatus. If an error is detected, retransmit the initial transmission signal, where the retransmission matrix consists of the components of the initial transmission matrix, which is different from the initial transmission matrix, and is a linear distributed code with the same capacity and diversity gain as the initial transmission matrix. The present invention provides a retransmission method of a multi-antenna transmission apparatus comprising transmitting a first retransmission signal generated by encoding to a receiver.

According to the present invention, when the hybrid ARQ is applied in a communication system that encodes and transmits symbols with a linear dispersion code, the coupling effect between the initial transmission signal and the retransmission signal is maximized, thereby sufficiently improving performance during initial transmission. In the increased state, the maximum gain of retransmission can be obtained.

MIMO, Hybrid ARQ, Linear Distributed Code, Progressive Redundancy, Retransmission Method

Description

MIMO System using Hybrid ARQ Method and the Retransmission Method

1 is a block diagram illustrating a transmitter of a MIMO system to which a hybrid ARQ according to an embodiment of the present invention is applied.

2 is a block diagram illustrating a receiver of a MIMO system to which hybrid ARQ is applied according to an embodiment of the present invention.

3 is a flowchart illustrating LLR soft combining according to an embodiment of the present invention.

4 is a block diagram illustrating a process of performing STC combining and soft decision on an initial transmission signal and a retransmission signal according to an embodiment of the present invention.

5 is a block diagram illustrating generation of parity included in a retransmission signal when retransmission is performed according to an embodiment of the present invention.

6 is a block diagram illustrating a second type of retransmission scheme according to an embodiment of the present invention.

7 is a block diagram illustrating a third type of retransmission scheme according to an embodiment of the present invention.

The present invention relates to a multi-antenna transceiver and a retransmission method thereof for performing hybrid automatic retransmission.

Multiple Input Multiple Output (MIMO) The system is an evolution of the Single Input Single Output (SISO) system in which the transmitted signal reaches the receiver via a single path. In other words, the multipath effect is such that the transmitted signal reaches the receiver through various paths.

The MIMO system uses a plurality of antennas in hardware to implement various transmission / reception paths, and different time delays are applied to each of the plurality of paths to reach one receiver at different timings. Through this, the MIMO system has an advantage of increasing the efficiency of resource usage and various transmission / reception, compared to the existing SISO system, thereby improving transmission / reception performance.
The data rate, which is a measure of transmission and reception performance, is determined by variables such as maximum mutual information capacity (hereinafter referred to as capacity), diversity gain, and spectral efficiency.

delete

In order to obtain a high data rate, high spectral efficiency is required, and therefore, a design of a space time code is required to obtain a high capacity. Linear Dispersion Code, which is a representative space time code, has a simple encoding and has a space domain and a time domain or a space domain and a frequency domain. Diversity on the Frequency Domain can be flexibly adjusted, making it easier to control the data rate, and the complexity of detection is similar compared to BLock ASynchronous Transmission (BLAST). The coding gain is large.

When the Hybrid Automatic Repeat reQuest (hereinafter referred to as Hybrid ARQ) protocol is applied to the MIMO system, the additional amount of information obtained during retransmission may be a space time code, particularly a space time block code. Code), which is due to the nature of transmitting signals to multiple antennas.

As a technology related to data retransmission of a MIMO system to which the related art hybrid ARQ protocol is applied, US Patent Publication 2004/0057530 A1 'Incremental Redundancy with Space-Time codes' (2004.03.25).

However, the data retransmission technique proposed in the prior US Patent Publication 2004/0057530 A1 refers to a technique for a case where the symbols of the initial transmission signal are transmitted in the form of a transmission matrix composed of a combination of the symbols through space-time encoding. There was not. In other words, in order to reduce the error due to fading of a transmitted signal, a retransmission method for a transmission method that has a diversity effect and a capacity as large as possible and a solution for a method of combining a received signal after retransmission cannot be provided. It was.

The technical problem to be solved by the present invention is to solve this problem, and to provide a retransmission signal having the same capacity and diversity gain as the capacity and diversity gain of the initial transmission signal, multiple performing hybrid automatic retransmission An antenna transceiver and a retransmission method thereof are provided.

In order to achieve the technical problem, the present invention, the step of encoding the initial transmission signal transmitted to the receiving device in the form of an initial transmission matrix, which is a linear distributed code, and transmits, and receiving an error check result for the initial transmission signal from the receiving device And when an error is detected in the initial transmission signal, retransmit the initial transmission signal, wherein the retransmission matrix is composed of the components of the initial transmission matrix, which is different from the initial transmission matrix, and has the same capacity and diversity gain as the initial transmission matrix. A method for retransmitting a multi-antenna transmitter comprising transmitting a first retransmission signal generated by encoding a linear distributed code to a receiver.

In addition, in order to achieve the second technical problem, the present invention encodes and transmits a codeword transmitted to a receiver in the form of an initial transmission matrix, which is a linear distributed code, and receives an error check result for the codeword from the receiver. If an error is detected in the codeword and the codeword, the first parity for error correction is added to the codeword, and then the codeword or a part of the codeword is retransmitted in a matrix, where the retransmission matrix is formed of components of the initial transmission matrix. A first retransmission generated by encoding the first parity in the form of the initial transmission matrix, wherein the first parity is encoded in the form of an initial transmission matrix, which is different from the initial transmission matrix and has the same capacity and diversity gain as the initial transmission matrix. The present invention provides a retransmission method of a multi-antenna transmitter including transmitting a signal to the receiver.

In order to achieve the third technical problem, the present invention encodes a codeword including an information word and an initial parity in the form of an initial transmission matrix, which is a linear distributed code, and transmits the codeword to a receiving device. Receiving an error check result and if an error is detected in the codeword, after adding a first parity for error correction to the information word, the information word is a retransmission matrix, where the retransmission matrix is composed of the components of the initial transmission matrix. Is a linear distributed code that is different from the transmission matrix and has the same capacity and diversity gain as the initial transmission matrix, and the first parity encodes the first retransmission signal generated by encoding the initial transmission matrix. Provided is a retransmission method of a multi-antenna transmitter including transmitting to a receiver.

In addition, the present invention, in order to achieve the fourth technical problem, performing an error check on the retransmitted signal retransmitted from the transmitting apparatus for the initial transmission signal, if an error is detected in the retransmission signal, the initial transmission signal and retransmission Converting the first LLR vector generated by the LLR (Log Likelihood Ratio) soft combining signal into the information word, detecting the channel variation width of the initial transmission signal and the retransmission signal and comparing it with a predetermined reference value, and the channel variation width using the reference value. If exceeded, performing an error check on the information word, wherein the retransmission signal consists of the components of the initial transmission matrix that encodes the initial transmission signal, but differs from the initial transmission matrix and has the same capacity as the initial transmission matrix. Multi-antenna receiver, a signal encoded with a retransmission matrix, a linear dispersion code with diversity gain It provides error checking methods.

In addition, in order to achieve the fifth technical problem, the present invention is to perform an error check on the first retransmission signal retransmitted from the transmitting apparatus for the initial transmission signal, if an error is detected in the first retransmission signal, The first LLR vector generated by LLR soft combining the initial transmission signal and the initial transmission signal encoded in the form of the retransmission matrix and the first parity for error correction included in the first retransmission signal are decoded together and converted into information information. And detecting the channel fluctuation widths of the initial transmission signal and the first retransmission signal and comparing them with a predetermined reference value, and if the channel fluctuation width exceeds the reference value, performing an error check on the information word. The retransmission signal is composed of components of the initial transmission matrix that encodes the initial transmission signal, but is different from the initial transmission matrix and is identical to the initial transmission matrix. Provides a capacitive city and the error checking method of diversity linear dispersion code of receiving the multiplexed into a signal encoded with the retransmission matrix by adding a first parity for the error correction encoding to the initial transmission matrix signal the antenna device having the gain.

In addition, the present invention, in order to achieve the sixth technical problem, performing an error check on the first retransmission signal retransmitted from the transmitting apparatus for the initial transmission signal including the information word and the initial parity, the first retransmission If an error is detected in the signal, converting the first LLR vector generated by LLR soft combining the information word of the first retransmission signal and the information word of the initial transmission signal to the information word, the initial transmission signal and the first retransmission signal. Detecting the channel variability and comparing it with a predetermined reference value, and if the channel variability exceeds the reference value, the error check is performed by decoding the information word, the initial parity and the first parity for error correction included in the first retransmission signal. Wherein the first retransmission signal consists of components of an initial transmission matrix that encodes the initial transmission signal, Is a signal obtained by adding a first parity for error correction encoded with an initial transmission matrix to an information word encoded with a first retransmission matrix, which is a linear dispersion code having the same capacity and diversity gain as the initial transmission matrix. An error checking method of a multi-antenna receiver is provided.

In addition, in order to achieve the seventh technical problem, the present invention encodes a channel encoder and a codeword for generating a codeword by encoding an information word for transmission and a first parity for error correction together with a linear distributed code. And a space time code (STC) encoder for generating a retransmission signal having the same capacity and diversity gain as the initial transmission signal, and transmitting the same to the receiving device. The retransmission signal includes an initial transmission matrix for encoding the initial transmission signal. The present invention provides a multi-antenna transmitter comprising a component, which is a first retransmission matrix different from the initial transmission matrix.

In order to achieve the eighth technical problem, the present invention provides an LLR calculator for generating an LLR vector using an initial transmission signal and the retransmission signal when an error is detected in the retransmission signal, and an LLR vector generated by the LLR calculator. The present invention provides a multi-antenna receiver including a channel decoder for converting a word into an information word and an error check for the information word, and a cyclic redundancy check (CRC) check unit for transmitting a result of the error check to a transmitting device.

DETAILED DESCRIPTION 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 may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like parts throughout the specification.

In addition, when a part is said to "include" a certain component, it means that it may further include other components, without excluding other components unless otherwise stated.

1 is a block diagram illustrating a transmitter of a MIMO system to which a hybrid ARQ according to an embodiment of the present invention is applied. The transmitter 100 includes a cyclic redundancy check (CRC) encoder 110, a channel encoder 120, a modulator 130, a space time code (STC) encoder 140, a signal converter 150, and a multiple antenna unit 160. ).

The CRC encoder 110 adds a CRC parity to the signal to be transmitted and encodes it as an information word, and the channel encoder 120 receives the information word and performs parity for error correction according to a predetermined code rate. Adding a parity, that is, encoding, creates and outputs a codeword. The modulator 130 performs phase modulation on the codeword received from the channel encoder 120. The STC encoder 140 receives the modulated signal from the modulator 130 and encodes it into a space time code to increase the capacity and the diversity gain. The signal conversion unit 150 receives the signal encoded by the STC encoder 140, converts and amplifies an analog signal so as to be propagated through the multi-antenna unit 160, and the multi-antenna unit 160 converts the signal. Receive and send.

2 is a block diagram illustrating a receiver of a MIMO system to which hybrid ARQ is applied according to an embodiment of the present invention. The receiver 200 includes the multiple antenna unit 210, the signal converter 220, the STC decoder 230, the LLR (Log Likelihood Ratio) calculator 240, the channel decoder 250, and the CRC checker 260. Include. The multi-antenna 210 receives an analog signal transmitted by the transmitter (100 in FIG. 1) and transmits the analog signal to the signal converter 220. The signal converter 220 converts the received signal into a discontinuous signal (received signal vector) and transmits the signal to the STC decoder 230. The STC decoder 230 detects the signal vector transmitted by the transmitter (100 in FIG. 1) from the received received signal vector and transmits the detected signal vector to the LLR calculator 240. In the detection process, the STC decoder 230 uses fading coefficients and noise estimated by the receiver 200. The LLR calculator 240 calculates Log Likelihood Ratios (LLR) values of the received signals, and the channel decoder 250 receives the LLR values and converts them into information words. The CRC checker 260 receives the information word from the channel decoder 250 and performs a CRC check to determine whether there is an error. According to the determination result, the CRC checker 260 transmits an ACK signal if no error is found and a NACK signal to the transmitter (100 in FIG. 1) through the multiple antenna unit 210 if an error is found.

The transmitting unit (100 in FIG. 1) receiving the ACK signal next processes the signal to be transmitted to the receiving unit 200 in the same procedure as before and transmits the same to the receiving unit 200. On the other hand, when the transmitter (100 in FIG. 1) receives the NACK signal from the receiver 200, it retransmits the initially transmitted signal.

The retransmission scheme of the MIMO system using hybrid ARQ according to the embodiments of the present invention shown in FIGS. 1 and 2 is a first type using chase combining and a second using gradual redundancy. There are three types, three. First, a first type of retransmission scheme using a chase combining technique will be described.

는 수학식 1과 같다.If the number of transmit antennas is M and the block size of the space-time encoding block is T, the initial transmission matrix obtained by encoding the initial transmission signal with a linear dispersion code.

Is the same as Equation 1.

와

는 M×T 복소수 행렬,

는 복소수

의 켤레복소수,

는 심볼, q는 심볼 인덱스) (From here,

Wow

Is an M × T complex matrix,

Is a complex number

Complex of,

Is a symbol, q is a symbol index)

로 인코딩하거나, 채널 인코더(도 1의 120)를 이용하여 초기 전송신호의 정보어 중 오류가 존재하거나 오류의 정도가 심각한 특정 부분에 오류정정을 위한 패러티(Parity)를 추가하여 코드워드(Codeword)로 인코딩한 후, STC 인코더(도 1의 140)를 이용하여 재전송 행렬

로 인코딩한다. 이때, 송신안테나의 개수와 시공간 인코딩 블록의 크기를 각각 2라고 하면, 초기 전송행렬

와 재전송 행렬

는 다음과 같은 2×2행렬이다.When an error is detected in the initial transmission signal transmitted by the transmitter (100 in FIG. 1), the receiver (200 in FIG. 2) transmits only a NACK signal to the transmitter (100 in FIG. 1) or an error in the information word of the initial transmission signal. Information on a specific part present or a specific part in which the detected error is serious than a predetermined reference value may be transmitted to the transmitter (100 of FIG. 1) together with the NACK signal. When the transmitter (100 in FIG. 1) receives a NACK signal from the receiver (200 in FIG. 2), the STC encoder (140 in FIG. 1) retransmits the initial transmission signal using a matrix.

Codeword by adding a parity for error correction to a specific part where an error exists or a serious degree of error among information words of an initial transmission signal using a channel encoder (120 of FIG. 1). Is encoded using the STC encoder (140 in FIG. 1).

Encode to. In this case, if the number of transmission antennas and the size of the space-time encoding block are each 2, the initial transmission matrix

And retransmission matrix

Is a 2x2 matrix

행

열의 원소

는 심볼

의 선형 조합(Linear Combination),

는 안테나의 번호) (From here,

line

Elements of heat

Symbol

Linear Combination of,

Is the number of the antenna)

In brief, Equation 2

는 초기 전송행렬

와 같이 여전히 선형 분산 코드(Linear Dispersion Code)이며, 초기 전송행렬

와 동일한 캐패시티와 다이버시티 이득(Diversity Gain)을 갖는다.At this time, the retransmission matrix

Is the initial transfer matrix

Is still the Linear Dispersion Code,

It has the same capacity and diversity gain as

을 수신한 수신부(도 2의 200)는 다음의 제1 과정 내지 제3과정을 수행한다. 제1 과정은 재전송 행렬

로 전송한 신호를 디텍션하여 채널 디코더(도 2의 250)를 거쳐 오류정정 후, 오류를 검사하는 것이다. 이때, 오류가 검출되면 아래에 기술하는 제2 과정 또는 제3 과정을 수행한다.Retransmission Matrix from Transmitter (100 in Figure 1)

The receiving unit 200 of FIG. 2 performs the following first to third processes. The first process is the retransmission matrix

After detecting the signal transmitted through the channel decoder (250 of FIG. 2) and correcting the error, the error is checked. At this time, if an error is detected, a second process or a third process described below is performed.

의 LLR벡터와 재전송 행렬

의 LLR 벡터를 LLR 소프트 컴바이닝(Soft Combining)하여 LLR 벡터를 구하고, 이 LLR 벡터를 채널 디코더(도 2의 250)에 입력하여 오류를 정정하고 오류를 검사하는 것이다. The second process is the initial transmission matrix in the LLR calculator (240 in FIG. 2)

LLR vector and retransmission matrix

LLR vector is obtained by LLR soft combining to obtain an LLR vector, and the LLR vector is input to a channel decoder (250 of FIG. 2) to correct an error and check an error.

In the third process, after STC combining is performed in the STC decoder 230 of FIG. 2, soft decision is performed to obtain an LLR vector, and the LLR vector is a channel decoder 250 of FIG. 2. To correct errors and check for errors. Through STC combining, a signal-to-noise ratio (hereinafter referred to as SNR) gain is obtained, which increases the absolute value of the LLR, thereby increasing the probability of error correction using a channel decoder.

와 재전송 행렬

의 채널변동폭이 기설정된 기준값 이상일 때 오류정정 효과가 크며, 제3 과정은 초기 전송행렬

와 재전송 행렬

의 채널변동폭이 기설정된 기준값 이하인 경우에 효과가 크다. 이를 위해, STC 디코더(도 2의 230)는 수신부(도2의 200) 관리자에 의해 설정되는 기준값을 저장한다. 수신부(도 2의 200)는 송신부(도 1의 100)로부터 재전송 행렬

을 수신하면, 제1 과정을 진행하여 오류를 검사한 후, STC 디코더(도 2의 230)에 저장된 기준값을 이용하여 채널변동폭과 기설정된 기준값의 크기를 비교한다. 수신부(도 2의 200)는 이 비교 결과에 따라 채널변동폭이 기설정된 기준값 이상이면 제2과정만을 진행하고, 채널변동폭이 기설정된 기준값 이하이면 제2 과정과 제3과정을 차례대로 진행한다. 여기에서, 채널변동폭은 송신부(도1의 100)에서 초기 전송행렬

와 재전송 행렬

가 수신부(200)에 도달할 때까지 전파매질을 통과하는 동안에 겪는 페이딩(Fading)의 차이를 나타낸다.Of these, the second process is the initial transmission matrix.

And retransmission matrix

The error correction effect is large when the channel variability of is greater than or equal to the preset reference value.

And retransmission matrix

The effect is great when the channel variability of is less than or equal to the preset reference value. To this end, the STC decoder 230 of FIG. 2 stores reference values set by the receiver (200 of FIG. 2) manager. The receiver (200 in FIG. 2) retransmits the matrix from the transmitter (100 in FIG. 1).

When receiving, after checking the error by proceeding to the first process, the channel variation width and the preset reference value are compared using the reference value stored in the STC decoder (230 of FIG. 2). According to the comparison result, the receiver (200 of FIG. 2) proceeds only the second process if the channel variability is greater than or equal to the preset reference value, and proceeds to the second process and the third process if the channel variability is less than or equal to the preset reference value. Here, the channel variance is the initial transmission matrix at the transmitter (100 in FIG. 1).

And retransmission matrix

Represents the difference in fading experienced while passing through the propagation medium until it reaches the receiver 200.

LLR soft combining performed in the second process will now be described with reference to FIG. 3.

의 형태라고 하면, i+1번째 전송신호는 재전송 행렬

의 형태이다. 이때, 송신부(도 1의 100)가 수신부(도 2의 200)로 전송하는 i번째 전송신호와 i+1번째 전송신호는 상호간에 반복되는 부분이 존재한다. 본 발명의 실시예에 따른 LLR 소프트 컴바이닝은 i번째 전송신호와 i+1번째 전송신호 중 반복되는 부분을 구성하는 심볼들에 대하여 비트단위 또는 심볼단위로 LLR의 절대값을 비교하여 LLR의 절대값이 큰 LLR값들로 구성되는 LLR 벡터를 생성하는 것으로, 그 생성 과정은 다음과 같다.3 is a flowchart illustrating LLR soft combining according to an embodiment of the present invention. For convenience of description, the i-th transmission signal transmitted from the transmitter (100 in FIG. 1) to the receiver (200 in FIG. 2) is initially transmitted in one hybrid ARQ.

, I + 1 th transmission signal is a retransmission matrix

In the form of. At this time, the i-th transmission signal and the i + 1-th transmission signal transmitted by the transmitter (100 in FIG. 1) to the receiver (200 in FIG. 2) may be repeated. In the LLR soft combining according to the embodiment of the present invention, the absolute value of the LLR is compared by comparing the absolute value of the LLR in units of bits or symbols with respect to symbols constituting a repeated portion of the i th transmission signal and the i + 1 th transmission signal. To generate an LLR vector composed of large LLR values, the generation process is as follows.

을 수신한 수신부는 STC 디코더(도 2의 230)를 이용하여 재전송 행렬

를 구성하는 복수의 비트(Bit) 혹은 복수의 심볼(Symbol) 각각의 LLR값으로 이루어지는 LLR 벡터 B를 계산한다(S310). 이때, LLR 벡터 B는 복수의 비트 혹은 심볼의 LLR값인 b₁, b₂, … , b_k로 이루어지며, k는 LLR 벡터 B의 전체 비트 혹은 심볼의 개수이다.Retransmission Matrix as i + 1th Transmission Signal

Receiving unit receives the retransmission matrix using STC decoder (230 of FIG. 2)

An LLR vector B consisting of LLR values of each of a plurality of bits or symbols is formed (S310). At this time, the LLR vector B is b ₁ , b ₂ ,..., LLR values of a plurality of bits or symbols. , b _k , where k is the total number of bits or symbols of the LLR vector B.

를 구성하는 복수의 비트 혹은 복수의 심볼 각각의 LLR값으로 이루어지는 LLR 벡터 A는 i번째 전송신호 수신시 STC 디코더(도 2의 230)에서 계산되어 이미 LLR 계산부(도 2의 240)에 저장되어 있다(S320). 이때, LLR 벡터 A는 복수의 비트 혹은 심볼의 LLR값인 a₁, a₂, … , a_k로 이루어지며, k는 LLR 벡터 A의 전체 비트 혹은 심볼의 개수이다.On the other hand, the initial transmission matrix that is the i-th transmission signal

The LLR vector A consisting of LLR values of each of a plurality of bits or a plurality of symbols constituting the L is calculated by the STC decoder (230 of FIG. 2) when the i-th transmission signal is received and is already stored in the LLR calculator (240 of FIG. 2). There is (S320). In this case, the LLR vector A is a ₁ , a ₂ ,..., LLR values of a plurality of bits or symbols. , a _k , where k is the total number of bits or symbols of the LLR vector A.

The LLR calculator 240 sets the bit number or symbol number to "1" (S330), and compares the size of the bit number or symbol number with the size of the total number of bits or symbols (S340). If the size of the bit number or symbol number is less than or equal to the size of the total number of bits or symbols, the LLR calculator (240 in FIG. 2) compares the absolute value of b ₁ of LLR vector B with a ₁ of LLR vector A. (S350). As a result of the comparison in step S350, the LLR calculator 240 selects one LLR value having a large absolute value from a ₁ and b ₁ and stores the LLR value (S360 and S370). The LLR calculator 240 (in FIG. 2) increases the bit number or the symbol number by "1" (S380), and repeats the operation after step S340. If the size of the bit number or symbol number is larger than the total number of bits or symbols, the LLR calculator (240 in FIG. 2) may include an LLR including LLR values of bits or symbols selected and stored in step S360 or S370. The vector is transferred to the channel decoder 250 of FIG. 2 and the LLR soft combining is terminated (S390).

The STC combining performed in the third process is as follows.

, 제1차 재전송 시의 채널행렬을

이라고 하면, STC 컴바이닝에 사용되는 채널행렬

의 (i, j)번째 원소는

의 (i, j)번째 원소와

의 (i, j)번째 원소의 평균값이다. 초기 전송행렬

와 재전송 행렬

의 i번째 열벡터를 각 각

와

,

와

에 해당되는 열벡터 형태의 초기 수신 신호열과 재전송된 수신 신호열을 각각 와

, 수신단의 수신신호 측정시에 더해지는 잡음 열벡터를 각각

,

로 표시하면, STC 컴바이닝은 수학식 4와 같다.First, the channel matrix is a matrix having the (i, j) th fading coefficient experienced by the signal received by the i th receive antenna from the j th transmit antenna. The channel matrix of the initial transmission

, The channel matrix at the first retransmission

Is the channel matrix used for STC combining.

The (i, j) th element of

With the (i, j) th element of

Average value of the (i, j) th element of. Initial transmission matrix

And retransmission matrix

I-th column vector of each

Wow

,

Wow

Each of the initial received signal sequence and the retransmitted received signal sequence in the form of a column vector corresponding to Wow

Each noise column vector is added to the receiver when the received signal is measured.

,

In this case, the STC combining is shown in Equation 4.

(Where T is the size of the space-time encoding block.)

On the other hand, when the channel fluctuation range is detected to be equal to or less than the reference value and the second process and the third process are sequentially performed, the LLR calculator (240 in FIG. 2) may use one of the LLR vector obtained in the second process and the LLR vector obtained in the third process. Is selected and delivered to the channel decoder 250 of FIG. 2. At this time, to select one LLR vector of the two vectors, the LLR calculator (240 of FIG. 2) calculates the standard deviation of the absolute value of the absolute value of the LLR and the absolute value of the LLR of the two LLR vectors. According to this calculation result, the LLR calculator 240 selects an LLR vector having a higher average value of the absolute value of the LLR and a smaller standard deviation of the absolute value of the LLR.

When the number of receive antennas is 2, the STC combining performed in the third process may be represented as an equation.

는

번째 수신 안테나와

번째 송신 안테나의 페이딩 계수(Fading Coefficient),

는 초기 전송 시

번째 수신 안테나가

번째 슬롯타임(Slot Time)에 수신하는 신호,

는 재전송 시

번째 수신 안테나가

번째 슬롯타임에 수신하는 신호,

와

는 각각 초기 전송 시와 재전송 시에

번째 수신 안테나가

번째 슬롯타임(Slot Time)에 수신하는 신호에 더해지는 잡음) (From here,

Is

With the first receiving antenna

Fading coefficient of the first transmit antenna,

At initial transfer

The first receiving antenna

Signal received in the first slot time,

On resend

The first receiving antenna

The signal received at the first slot time,

Wow

At initial transmission and retransmission respectively

The first receiving antenna

Noise added to the received signal at the first slot time)

에 대한 ML(Maximum Likelihood) 연판정(Soft Decision)은 다음과 같다.From Equation 5, each

The maximum likelihood soft decision for ML is

는

에 대한 ML 연판정)(From here,

Is

ML soft decision for

는 심볼들

와 그 켤레 복소수(Conjugate)의 선형 매핑(Linear mapping)이므로, 초기 전송행렬

에 대한 ML 연판정(Soft Decision)으로부터 선형 역매핑을 통해 심볼들

에 대한 ML 연판정도 쉽게 구할 수 있다. Initial transmission matrix

Are symbols

Since it is a linear mapping of complex conjugates with their conjugates, the initial transmission matrix

Symbols via linear demapping from ML Soft Decision

You can easily get an ML plate for.

와 재전송 행렬

은 다음과 같은 2 x T 행렬로 나타낼 수 있다. If the number of transmit antennas is 2, the number of receive antennas is N, and the size of the space-time encoding block is T, the initial transmission matrix

And retransmission matrix

Can be represented by the following 2 x T matrix.

는 초기 전송행렬

와 동일한 캐패시티와 다이버시티를 가지므로 제2 과정을 통해 충분한 이득을 얻는다. At this time, the retransmission matrix

Is the initial transfer matrix

Since it has the same capacity and diversity as, a sufficient gain is obtained through the second process.

If the channel fluctuation range is detected to be less than or equal to the reference value and the third process is used, Equation 5 is generalized as follows.

는

번째 수신 안테나와

번째 송신 안테나의 페이딩 계수,

는 처음 전송 시에

번째 수신 안테나가 받은 초기 전송 행렬의

번째 열(Column)에 해당되는 수신 신호,

는 재전송 시에

번째 수신 안테나가 받은 재전송 행렬의

번째 열(Column)에 해당되는 수신 신호,

와

는 각각

와

에 더해지는 잡음)(From here,

Is

With the first receiving antenna

Fading coefficient of the first transmit antenna,

On the first transfer

Of the initial transmission matrix received by the first receive antenna

The received signal corresponding to the first column,

At retransmission

Of the retransmission matrix received by the first receive antenna

The received signal corresponding to the first column,

Wow

Are each

Wow

Noise added to)

When the number of receive antennas is N and the size of the space-time encoding block is T, Equation 6 is generalized as follows.

(i = 1, 2, j = 1, … , T)의 ML 연판정(Soft Decision)은 다음과 같다.From Equation 8 and Equation 9

ML Soft Decision of (i = 1, 2, j = 1, ..., T) is as follows.

는 초기 전송행렬

에 대한 ML 연판정) (From here,

Is the initial transfer matrix

ML soft decision for

From Equations 8 to 10,

는 각각

,

,

의 선형조합)(From here,

Are each

,

,

Linear combination of

,

가 AWGN(Additive white Gaussian Noise)이고 그 분포가

라면

의 분포도

과 같다. 초기 전송행렬

는 심볼들

로 이루어진 선형 분산 코드이며, 선형매핑 함수 F로 표현하면 다음과 같다. At this time,

,

Is AWGN (Additive white Gaussian Noise) and its distribution is

Ramen

Distribution

Is the same as Initial transmission matrix

Are symbols

A linear variance code consisting of

Equation 12 may be expressed as Equation 13 using a coefficient matrix A.

From Equations 11 to 13,

은 여전히

분포를 따르게 된다. 따라서 수학식 14를 이용하여, 수신부(도 2의 200)에서 측정하여 계산할 수 있는

로부터

의 LLR 값들을 구할 수 있다. 이 LLR 값들은 수학식 9로 나타낸 STC 컴바이닝으로부터 얻어지는 SNR 이득이 반영된 값들이므로 채널 디코더(도 2의 250)의 오류정정능력을 높여준다. At this time

Is still

Will follow the distribution. Therefore, by using Equation 14, it can be calculated by measuring in the receiver (200 of FIG. 2)

from

The LLR values of can be obtained. These LLR values reflect the SNR gain obtained from the STC combining represented by Equation 9, thereby enhancing the error correction capability of the channel decoder 250 of FIG. 2.

4 is a block diagram illustrating a process of performing STC combining and soft decision on an initial transmission signal and a retransmission signal according to an embodiment of the present invention.

FIG. 4 illustrates a process from Equation 5 to Equation 14 for the case where the number of transmitting antennas and receiving antennas and the size T of the space-time encoding block are both 2. FIG.

를 입력 받아 계수 행렬 A를 이용한 인코딩을 수행하고, 이를 통해 수학식 2로 나타낸 초기 전송행렬

를 생성한다. 이후, 수신부(도 2의 200)로부터 NACK 신호를 수신한 송신부(도 1의 100)는 심볼들

의 켤레 복소수인

를 계수 행렬

를 이용하여 인코딩함으로써 재전송 행렬

를 생성한다. 이때, 계수 행렬 A와

는 다음과 같다.The STC encoder (140 in FIG. 1) of the transmitter (100 in FIG. 1) may interleave symbols during initial transmission.

Is encoded using the coefficient matrix A, and the initial transmission matrix represented by Equation 2 is performed.

Create Then, the transmitter (100 in FIG. 1) that receives the NACK signal from the receiver (200 in FIG.

Complex conjugate

Coefficient matrix

Retransmission matrix by encoding using

Create In this case, the coefficient matrix A and

Is as follows.

와 재전송 행렬

, 각각의 수신 시 발생하는 페이딩 계수 행렬을 측정한다. 이하, 초기 전송행렬

의 수신시 측정되는 페이딩 계수 행렬을 H₀, 재전송 행렬

의 수신 시 측정되는 페이딩 계수 행렬을 H₁으로 나타낸다.On the other hand, the receiving unit (200 in Fig. 2) is the initial transmission matrix

And retransmission matrix

We measure the fading coefficient matrix that occurs at each reception. Initial transmission matrix

The fading coefficient matrix measured at the reception of H ₀ , is the retransmission matrix.

The fading coefficient matrix measured at reception of is denoted by H ₁ .

와

을 구한 후 수학식 5를 이용하여 STC 디코더(도 2의 230)는 STC 연판정을 수행하는 데 그 과정은 다음과 같다. When receiving STC decoder (Fig. 200 in Fig. 2) (Fig. 230 in Fig. 2) is compared to the size of the H ₀ and H ₁ is less than the reference value, the channel variation preset δ, the sum of H ₀ and H ₁ "2" Divide by to get the average fading coefficient matrix H

Wow

The STC decoder (230 of FIG. 2) performs the STC soft decision using Equation 5 after the procedure is as follows.

를 계산하고, 이를 이용하여,

를 계산한다. 수학식 14로 나타낸 것과 같이, 계산된

값에 계수 행렬

를 곱하여 연판정 값을 구한다. The STC decoder 230 of FIG. 2 may be configured according to the number of transmit antennas and receive antennas.

Calculate and use it to

Calculate As shown in equation (14),

Coefficient matrix to values

Multiply by to get the soft decision value.

는 3 x T 행렬이고, 심볼 인덱스

는

또는

이다. 수신부(도 2의 200)로부터 NACK 신호를 수신한 송신부(도 1의 100)는 초기 전송행렬

로 전송한 코드워드를 제1 재전송행렬

로 인코딩하여 재전송하는데, 이때 제1 재전송행렬

는 다음의 수학식 16 내지 수학식 18 중 하나의 형태이다.Now, a case in which the number of transmit antennas is 3, the number of receive antennas is N, and the size of the space-time encoding block is T will be described. At this time, the initial transmission matrix

Is a 3 by T matrix, and the symbol index

Is

or

to be. The transmitter (100 in FIG. 1), which has received the NACK signal from the receiver (200 in FIG. 2), initially transmits a matrix.

Retransmission matrix of codewords transmitted to

Encodes and retransmits the first retransmission matrix

Is one of the following equations (16) to (18).

는 선형 분산 코드이며, 초기 전송행렬

와 동일한 캐패시티와 다이버시티를 가진다. 그러므로, 제2 과정을 통하여 충분한 이득을 얻는다. Retransmission Matrix in Equations 16-18

Is the linear distribution code, and the initial matrix

Has the same capacity and diversity as Therefore, a sufficient benefit is obtained through the second process.

When the channel fluctuation range is detected to be equal to or less than the reference value and the third process is performed, the STC combining for each of Equations 16 to 18 is represented by Equations 19 to 21.

에 대하여 수학식 19 내지 수학식 21의 STC 컴바이닝을 통해

의 연판정을 구한다. 이를 통해 구해지는 초기 전송행렬

의 연판정(Soft Decision) 값

를 이용하여 수학식 14와 같이 정보어를 구성하는 심볼

의 LLR값을 얻는다. When using the third process, each row

With respect to the STC combining of Equations 19 to 21 with respect to

Obtain a soft decision. Initial transmission matrix obtained through this

Soft Decision Values

Symbol constituting the information word as shown in Equation 14 using

Get the LLR of.

는 다음과 같이 나타낼 수 있다. Equations 16 to 18 give the same type of retransmission transformation for all slot times, and randomly select one of the three forms shown in each column of Equations 16 to 18 at each slot time, or sequentially Three forms can be used in turn. For example, the retransmission matrix

Can be expressed as:

마다 그 형태에 맞게 수학식 19 내지 수학식 21 중 하나의 방식으로 소프트 컴바이닝한다. In this case, each column

Each time, the soft combining is performed in one of the equations (19) to (21) according to the form.

는 4 x T 행렬이고, 심볼 인덱스

는

또는

이다. NACK 신호를 수신한 송신단(도 1의 100)은 제1 재전송 행렬

를 아래에 나타낸 수학식 22와 같이 인코딩하여 수신단(도 2의 200)으로 정보어를 재전송한다.Now, a case in which the number of transmitting antennas is 4, the number of receiving antennas is N, and the size of the space-time encoding block is T will be described. At this time, the initial transmission matrix

Is a 4 by T matrix and symbol index

Is

or

to be. The transmitting end (100 in FIG. 1) receiving the NACK signal has a first retransmission matrix.

Is encoded as shown in Equation 22 below to retransmit the information word to the receiver (200 in FIG. 2).

를 사용한다. After the first retransmission of the transmitter (100 in FIG. 1) that receives the NACK signal, if the error is still detected in the receiver (200 in FIG. 2), the second retransmission is performed, and if the error is detected even after the second retransmission, the third is transmitted. Car retransmission is made. In the second retransmission, if the number of reception antennas is N and the size of the space-time encoding block is T, the following retransmission matrix for each case where the number of transmission antennas M is 2, 3 or 4 is as follows.

Use

If the number of transmit antennas is 2,

If the number of transmit antennas is 3,

If the number of transmit antennas is 4,

의 사용도 가능하다.If the number of transmit antennas is 4, the retransmission matrix represented by Equation 27 instead of Equation 26 is shown.

It is also possible to use.

은 제1차 재전송 행렬

와 같으며, 이를 수학식으로 나타내면 다음과 같다.Third retransmission matrix in case of attempting third retransmission due to error detection in second retransmission

Is the first retransmission matrix

It is as follows, which is represented by the following equation.

When the number of retransmissions increases, the following processing is performed to transmit one signal through a plurality of antennas.

가 수학식 27의 전송행렬을 사용한다면, 제 3차 재전송 행렬

는 수학식 28로 나타낸 전송행렬 대신 다음의 전송행렬을 사용한다.When the number of transmission antennas is 3, the transmitter (100 in FIG. 1) uses the transmission matrices of Equations 16, 17, and 18 sequentially during the first, third, and fifth retransmissions. If the number of transmit antennas is 4, the second retransmission matrix

Uses the transmission matrix of Equation 27, the third retransmission matrix

Uses the following transmission matrix instead of the transmission matrix shown in (28).

로서 수학식 28의 전송행렬을 사용하면, 짝수번째 재전송 행렬

와 홀수번째 재전송 행렬

각각에 대하여

를 재전송 회수의 상한 값까지 계속 적용한다. 반면, 제 3차 재전송 행렬

로 수학식 29의 전송행렬을 사용하는 경우에는,

를 재전송 회수의 상한 값까지 계속 적용한다. 여기에서,

이고,

이다. 이로 인해, 매 재전송 시의 재전송 행렬

는 마지막 재전송 시까지 초기 전송행렬

와 동일한 캐패시티와 다이버시티를 가진다. 또한, 송신부(도 1의 100)로부터 재전송 행렬

을 수신한 수신부(도 2의 200)는 앞서 언급한 것과 동일하게 제1 과정 내지 제3과정을 거쳐 LLR벡터를 구하고, 오류정정과 오류 검사를 진행한다. If the third retransmission matrix

Using the transmission matrix of equation (28) as an even-numbered retransmission matrix

And odd-numbered retransmission matrix

For each

Continue to apply up to the upper limit of the number of retransmissions. In contrast, the third retransmission matrix

In the case of using the transmission matrix of Equation 29

Continue to apply up to the upper limit of the number of retransmissions. From here,

ego,

to be. Because of this, the retransmission matrix at every retransmission

Is the initial transmission matrix until the last retransmission.

Has the same capacity and diversity as Further, the retransmission matrix from the transmitter (100 in FIG. 1)

Receiving unit (200 of FIG. 2) to obtain the LLR vector through the first to third processes in the same manner as mentioned above, the error correction and error check proceeds.

So far, the retransmission scheme using the Chase Combining technique, the first type, of the three retransmission schemes in the MIMO system using hybrid ARQ has been described. The second and third types of retransmission schemes with incremental redundancy will now be discussed.

와 재전송 행렬

및 재전송 행렬

의 변형은 제2, 제3 타입의 재전송 기법에도 적용된다. 제2 타입의 재전송 기법과 제3 타입의 재전송 기법은 재전송 요구를 수신한 전송부(도 1의 100)가 초기 전송신호 또는 초기 전송신호의 일부에 패러티를 추가하여 재전송 신호를 생성하고, 이를 수신부(도 2의 200)로 전송하는 것이다. 이때, 제2 타입과 제3 타입에 공통적으로 적용되는 추가 패러티의 생성을 도 5를 이용하여 설명한다. Initial transmission matrix mentioned earlier in describing Chase Combining technique

And retransmission matrix

And retransmission matrix

The modification of also applies to the second and third types of retransmission schemes. In the second type of retransmission scheme and the third type of retransmission scheme, a transmitter (100 of FIG. 1) receiving a retransmission request generates a retransmission signal by adding a parity to an initial transmission signal or a portion of the initial transmission signal, and the receiver (200 in Fig. 2). In this case, generation of additional parity commonly applied to the second type and the third type will be described with reference to FIG. 5.

5 is a block diagram illustrating generation of parity included in a retransmission signal when retransmission is performed according to an embodiment of the present invention.

The channel encoder (120 of FIG. 1) of the transmitter (100 of FIG. 1) is a parity for configuring a retransmission signal in advance in case retransmission is required when transmitting information to the receiver (200 of FIG. 2) in order to support hybrid ARQ. To generate a maximum number of retransmissions, the process is as follows.

로 표시하고, 기설정된 최대 재전송 횟수 L에 따라 생성되는 패러티

를 각각

,

, … ,

로 나타낸다. 또한,

는 부호율(Code Rate)을 나타내며, 초기 부호율

와 재전송 횟수

에 대응하는 부호율

, … ,

은 그 크기가

로 미리 설정된 값이다.

가 패리티

,

, … ,

를 연이어 덧붙인 것을 나타낸다면, 패러티

, 패러티

및 패러티

에 해당하는 부호율은 각각

,

및

와 같다. First, the number of retransmissions for transmitting a retransmission signal from the transmitter (100 in FIG. 1) to the receiver (200 in FIG. 2)

, Which is generated according to the preset maximum number of retransmissions L

Each

,

,… ,

Represented by Also,

Represents the code rate, and the initial code rate

And resend count

Code rate corresponding to

,… ,

Is that size

This is a preset value.

Parity

,

,… ,

Parity to indicate successive additions

, Parity

And parity

Code rate corresponding to

,

And

Same as

를 "1"로 설정하고(S410), 재전송횟수(

)의 크기와 기설정된 최대 재전송 횟수(L)의 크기를 비교한다(S420). 재전송 횟수의 크기가 최대 재전송 횟수의 크기보다 적거나 같으면, 기설정된 부호율

와

을 이용,

/

를 계산하여 인코딩을 위한 부호율로 입력하고,

를 채널인코더(도 1의 120)에 입력하여

에 대한 패러티

을 산출한다(S430). 채널 인코더(도 1의 120)는 재전송 횟수

를 1 증가시키고(S440), S420 단계 이후를 반복한다. S420 단계의 비교 결과, 재전송 횟수의 크기가 최대 재전송 횟수의 크기보다 크면, 채널 인코더(도 1의 120)는

부터 C _{L -1}에 대한 패러티

, … , P_L을 저장하고(S450), 패러티 생성과정을 종료한다. Channel encoder (120 in Figure 1) is the number of retransmissions

Is set to "1" (S410), and the number of retransmissions (

) And the size of the predetermined maximum number of retransmission (L) is compared (S420). If the size of the number of retransmissions is less than or equal to the size of the maximum number of retransmissions, the preset code rate

Wow

Using,

Of

Calculate and enter the code rate for encoding,

To the channel encoder (120 in FIG. 1)

Parity for

To calculate (S430). Channel encoder (120 in Figure 1) is the number of retransmissions

Increase by 1 (S440), and repeat after step S420. As a result of the comparison in step S420, if the size of the retransmission number is greater than the maximum retransmission number, the channel encoder (120 in FIG. 1) is

Parity for C _{L -1}

,… , P _L is stored (S450), and the parity generation process ends.

Now, the second type of retransmission scheme illustrated in FIG. 6 will be described with reference to generation of the additional parity described with reference to FIG. 5.

(이하,

라 칭함.)를 초기 전송행렬

의 형태로 인코딩하여 전송한다. 수신부(도 2의 200)의 채널 디코더(도 2의 230)는 송신부(도 1의 100)가 전송한

를 디코딩하여 오류를 검사한다. 수신부(도 2의 200)는 오류가 없으면 ACK신호를 송신부(도 1의 100)로 전송하고, 오류가 검출되면 NACK 신호를 송신부로 전송한다. 6 is a block diagram illustrating a second type of retransmission scheme according to an embodiment of the present invention. Transmitter (100 in Figure 1) is the initial transmission signal

(Below,

Is called the initial transmission matrix.

Encode and send in the form of. The channel decoder (230 of FIG. 2) of the receiver 200 (200 of FIG. 2) is transmitted by the transmitter (100 of FIG. 1).

Decode it to check for errors. If there is no error, the receiver (200 in FIG. 2) transmits an ACK signal to the transmitter (100 in FIG. 1), and if an error is detected, transmits a NACK signal to the transmitter.

(이하,

이라 칭함.)를 생성하여 수신부로 전송한다.

은 초기에 전송했던

에 패러티

을 추가한 후,

를 이루는 심볼들을 재전송 행렬

의 형태로 인코딩하고, 패러티

는 초기 전송행렬

의 형태로 인코딩한 것이다. 이하, 재전송 행렬

의 형태로 전송한

를

로 표기한다.
수신부(도 2의 200)의 채널 디코더(도 2의 230)는 송신부(도 1의 100)가 전송한

을 디코딩하여 오류를 검사한다. 수신부(도 2의 200)는 오류가 없으면 ACK신호를 송신부(도 1의 100)로 전송하는 한편,

와

을 삭제하여 다음 번에 전송될 신호를 수신할 준비를 한다. Transmitter that receives the NACK signal is a retransmission signal

(Below,

And transmits it to the receiver.

Was sent earlier

Parity on

After adding

Retransmission Matrix of Symbols

Encode in the form of, parity

Is the initial transfer matrix

Encoded in the form of. Retransmission Matrix

Sent in the form of

To

It is written as.
The channel decoder (230 of FIG. 2) of the receiver 200 (200 of FIG. 2) is transmitted by the transmitter (100 of FIG. 1).

Decode it to check for errors. If there is no error, the receiver (200 in FIG. 2) transmits an ACK signal to the transmitter (100 in FIG. 1).

Wow

Delete to prepare to receive the next signal to be transmitted.

delete

에서 오류가 검출되면,

와

를 체이스 컴바이닝(Chase Combining) 기법에서 소개한 제1, 제2 과정 혹은 제1 내지 제3 과정을 이용하여 컴바이닝(Combining)한 후, 패러티

과 함께 채널 디코더(도 2의 250)를 이용하여 디코딩하여 오류를 검사한다. 이때,

와

를 컴바이닝(Combining)한 결과를

로 표기한다. if,

If an error is detected at

Wow

After combining by using the first, second or first to third processes introduced in the Chase Combining technique, the parity

And decode using a channel decoder (250 of FIG. 2) to check for errors. At this time,

Wow

Combining the results

It is written as.

(이하,

라고 칭함.)를 생성하여 수신부로 전송한다.

는 패러티

에 패러티

를 추가한 후, 패러티

은 재전송 행렬

의 형태로 인코딩하고, 패러티

는 초기 전송행렬

의 형태로 인코딩한 것이다. 이하, 재전송 행렬

의 형태로 전송한 패러티

을

로 표기한다. As a result, when an error is detected again, the receiver 200 (in FIG. 2) transmits a NACK signal to the transmitter (100 in FIG. 1). Transmitter receiving the NACK signal is the second retransmission signal

(Below,

And transmit it to the receiver.

Parity

Parity on

After adding, parity

Is the retransmission matrix

Encode in the form of, parity

Is the initial transfer matrix

Encoded in the form of. Retransmission Matrix

Parity sent in the form of

of

It is written as.

,

및 패러티

의 LLR 벡터를 함께 연결하여 디코딩하고, 오류를 검사한다. 만약, 다시 오류가 검출되면, 패러티

과

를 제1, 제2 과정 혹은 제1 내지 제3 과정으로 컴바이닝(Combining)한 LLR 값들로 이루어진 벡터

를 만들고,

,

및

를 함께 연결하여 디코딩한다. The channel decoder 230 of FIG. 2 of the receiver 200 of FIG.

,

And parity

Link LLR vectors together to decode and check for errors. If an error is detected again, parity

and

Is a vector consisting of LLR values that are combined with the first, second or first to third processes.

Create

,

And

And decode them together.

번째 재전송 후에도 여전히 오류가 발견되면 송신부(도 1의 100)는 제

차 재전송 신호

(이하,

이라 칭함.)를 생성하여, 수신부로

번째 재전송을 실시한다. 이때,

는 2 이상의 자연수이다.

는 패러티

와 패러티

로 구성되며, 패러티

는 재전송 행렬

의 형태로 인코딩하고, 패러티

은 초기 전송행렬

의 형태로 시공간 인코딩한 것이다. 수신부(도 2의 200)의 채널 디코더(도 2의 230)는

,

, … ,

,

및

을 함께 연결하여 디코딩하고 오류를 검사한다. 수신부(도 2의 200)는 오류가 없으면 ACK신호를 송신부(도 1의 100)로 전송하는 한편,

,

, … ,

,

및

을 삭제하여 다음 번에 전송될 신호를 수신할 준비를 한다. 만약, 다시 오류가 검출되면, 패러티

와

를 제1, 제2 과정 혹은 제1 내지 제3 과정으로 컴바이닝(Combining)한 LLR값들로 이루어진 벡터

을 만들고,

,

, … ,

및

을 함께 연결하여 디코딩하고, 오류를 검사한다. Repeat this process

If the error is still found after the first retransmission, the transmitter (100 in FIG. 1)

Car retransmission signal

(Below,

To the receiving unit.

First retransmission. At this time,

Is a natural number of two or more.

Parity

And parity

Consist of parity

Is the retransmission matrix

Encode in the form of, parity

Is the initial transmission matrix

Space-time encoding in the form of. The channel decoder 230 of FIG. 2 of the receiver 200 of FIG.

,

,… ,

,

And

Connect together to decode and check for errors. If there is no error, the receiver (200 in FIG. 2) transmits an ACK signal to the transmitter (100 in FIG. 1).

,

,… ,

,

And

Delete to prepare to receive the next signal to be transmitted. If an error is detected again, parity

Wow

Is a vector consisting of LLR values that are combined with the first, second or first to third processes.

Create

,

,… ,

And

Connect together to decode and check for errors.

As described above, in the second type, since only the parities are transmitted during retransmission after the second retransmission, self-decoding is impossible without combining with the previously transmitted signal. On the other hand, unlike the second type of retransmission scheme, the third type of retransmission scheme is a method in which signals transmitted at every retransmission can be decoded by themselves without being combined with previously transmitted signals. Now, a third type of retransmission scheme will be described with reference to FIG. 7.

의 형태로 시공간 인코딩하여 수신부(도 2의 200)로 전송하는 초기 전송신호

는 앞서 제2 타입의 경우와 동일하다.7 is a block diagram illustrating a third type of retransmission scheme according to an embodiment of the present invention. The transmitting unit (100 in FIG. 1) initially transmits the matrix.

Initial transmission signal transmitted to the receiver (200 in FIG. 2) by space-time encoding in the form of

Is the same as the case of the second type.

를 디코딩하여 오류를 검사한다. 수신부(도 2의 200)는 오류가 없으면 ACK신호를 송신부(도 1의 100)로 전송하고, 오류가 검출되면 NACK 신호를 송신부로 전송한다. 이때, 수신부(도 2의 200)는 송신부(도 1의 100)로 초기 전송신호

를 구성하는 정보어 중 오류가 존재하는 특정 부분 또는 검출된 오류가 기설정한 기준치보다 심각한 특정 부분에 대한 정보를 NACK 신호와 함께 송신부(도 1의 100)로 전송할 수 있다. The channel decoder (230 of FIG. 2) of the receiver 200 (200 of FIG. 2) is transmitted by the transmitter (100 of FIG. 1).

Decode it to check for errors. If there is no error, the receiver (200 in FIG. 2) transmits an ACK signal to the transmitter (100 in FIG. 1), and if an error is detected, transmits a NACK signal to the transmitter. At this time, the receiving unit 200 of FIG. 2 transmits an initial transmission signal to the transmitting unit 100 of FIG. 1.

Information on a specific part in which an error exists or a specific part in which a detected error is serious than a preset reference value may be transmitted to the transmitter (100 in FIG. 1) together with the NACK signal.

을 수신부로 전송한다.

은

의 정보어(Information, I) 부분 또는

의 정보어 중 오류가 존재하거나 오류의 정도가 심각한 특정 부분에 패러티

을 추가한 후, 정보어는 재전송 행렬

의 형태로 인코딩하고, 패러티

은 초기 전송행렬

의 형태로 인코딩한 것이다. 이하, 초기 전송행렬

의 형태로 인코딩한 정보어를

, 재전송 행렬

의 형태로 인코딩한 정보어를

로 표기한다. The transmitter (100 in FIG. 1) receiving the NACK signal transmits a retransmission signal.

Send to the receiver.

silver

Information (I) part of

Parity in a specific part of an information word in which an error exists or is severe

After adding, the information word is retransmission matrix

Encode in the form of, parity

Is the initial transmission matrix

Encoded in the form of. Initial transmission matrix

Information words encoded in the form of

Retransmission matrix

Information words encoded in the form of

It is written as.

을 디코딩하여 오류를 검사하고, 오류가 없으면 ACK신호를 송신부로 전송하는 한편,

와

을 삭제하고 송신부(도 1의 100)로부터 다음 번에 전송될 신호를 수신할 준비를 한다. 만약,

에서 오류가 검출되면,

와

를 체이스 컴바이닝(Chase Combining) 기법에서 소개한 제1, 제2 과정 혹은 제1 내지 제3 과정을 이용하여 컴바이닝(Combining)한 후, 패러티

, 패러티

과 함께 채널 디코더(도 2의 250)에서 디코딩하여 오류를 검사한다. 이하,

와

를 컴바이닝(Combining)한 결과를

로 표기한다. The receiving unit (200 in FIG. 2) is transmitted by the transmitting unit (100 in FIG. 1).

Decode the signal to check for errors, and if there is no error, send an ACK signal to the transmitter.

Wow

Delete and prepare to receive a signal to be transmitted next from the transmitter (100 in FIG. 1). if,

If an error is detected at

Wow

After combining by using the first, second or first to third processes introduced in the Chase Combining technique, the parity

, Parity

In addition, the channel decoder (250 of FIG. 2) is decoded to check an error. Below,

Wow

Combining the results

It is written as.

를 수신부로 전송한다.

는 정보어에 패러티

를 추가한 후, 정보어는 제2차 재전송 행렬

의 형태로 인코딩하고, 패러티

는 초기 전송행렬

의 형태로 인코딩 한 것이다. 이하, 재전송 행렬

의 형태로 전송한 정보어를

로 표기한다. As a result, when an error is detected again, the receiver 200 (in FIG. 2) transmits a NACK signal to the transmitter (100 in FIG. 1). Transmitter receiving the NACK signal is the second retransmission signal

Send to the receiver.

Parity on information word

After adding, the information word is the second retransmission matrix.

Encode in the form of, parity

Is the initial transfer matrix

Will be encoded in the form of. Retransmission Matrix

Information words sent in the form of

It is written as.

를 디코딩하여 오류를 검사한다. 만약, 오류가 검출되면,

와

를 체이스 컴바이닝(Chase Combining) 기법에서 소개한 제1, 제2 과정 혹은 제1 내지 제3 과정을 이용하여 컴바이닝(Combining)한 후, 패러티

와 함께 채널 디코더(도 2의 250)를 이용하여 디코딩하여 오류를 검사한다. 이하,

와

를 컴바이닝(Combining)한 결과를

로 표기한다. The receiving unit (200 in FIG. 2) is transmitted by the transmitting unit (100 in FIG. 1).

Decode it to check for errors. If an error is detected,

Wow

After combining by using the first, second or first to third processes introduced in the Chase Combining technique, the parity

Decoded using a channel decoder (250 of FIG. 2) to check for errors. Below,

Wow

Combining the results

It is written as.

와 패러티

,

및

를 함께 디코딩하여 오류를 검사한다. If an error is detected again,

And parity

,

And

Decode together to check for errors.

번째 재전송 후에도 여전히 오류가 발견되면 송신부는 제i+1차 재전송 신호

을 수신부로 전송한다.

은 정보어에 패러티

을 추가한 후, 정보어는 제i+1차 재전송 행렬

의 형태로 인코딩하고, 패러티

는 초기 전송행렬

의 형태로 인코딩한 것이다. 이하, 재전송 행렬

의 형태로 전송한 정보어를

로 표기한다. Repeat this process

If the error is still found after the first retransmission, the transmitter transmits the i + 1st retransmission signal.

Send to the receiver.

Is a parity on information words

After adding, the information word is i + 1st retransmission matrix

Encode in the form of, parity

Is the initial transfer matrix

Encoded in the form of. Retransmission Matrix

Information words sent in the form of

It is written as.

을 디코딩하여 오 류를 검사한다. 만약,

에서 오류가 검출되면,

와

를 체이스 컴바이닝(Chase Combining) 기법에서 소개한 제1, 제2 과정 혹은 제1 내지 제3 과정을 이용하여 컴바이닝(Combining)한 후, 패러티

과 함께 채널 디코더(도 2의 250)를 이용하여 디코딩하여 오류를 검사한다. 이하,

와

를 컴바이닝(Combining)한 결과를

로 표기한다.The receiving unit (200 in FIG. 2) is transmitted by the transmitting unit (100 in FIG. 1).

Decode the error to check for errors. if,

If an error is detected at

Wow

After combining by using the first, second or first to third processes introduced in the Chase Combining technique, the parity

And decode using a channel decoder (250 of FIG. 2) to check for errors. Below,

Wow

Combining the results

It is written as.

와 패러티

,

,

, … ,

및

를 함께 디코딩하여 오류를 검사한다. If an error is detected again,

And parity

,

,

,… ,

And

Decode together to check for errors.

The embodiments of the present invention described above are not implemented only through the apparatus and the method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. Implementation may be easily implemented by those skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

By the above-described configuration, the spatio-temporal encoding matrix of the retransmission signal is fully utilized to take full advantage of the initial transmission signal matrix for encoding and transmitting symbols with a linear dispersion code. By having the advantages of this initial transmission matrix equally, it is possible to obtain a multi-antenna transmitter capable of sufficiently obtaining the gain of retransmission.

In addition, by maximizing the coupling effect between the initial transmission signal and the retransmission signal transmitted from the multi-antenna transmitter, a multi-antenna receiver capable of sufficiently enhancing error correction performance by using the initial transmission signal and subsequent retransmission signals can be obtained. have.

Claims (41)

A retransmission method of a multi-antenna transmitter for performing hybrid automatic retransmission in cooperation with a receiver, (a) encoding and transmitting an initial transmission signal transmitted to the reception device in the form of an initial transmission matrix, which is a linear distributed code, and receiving an error checking result of the initial transmission signal from the reception device; And (b) if an error is detected in the initial transmission signal, retransmit the initial transmission signal, wherein the retransmission matrix consists of components of the initial transmission matrix, which is different from the initial transmission matrix and is the same as the initial transmission matrix. Transmitting a first retransmission signal generated by encoding a linear distributed code having a city and diversity gain to the receiver; Retransmission method of a multi-antenna transmitter comprising a. The method of claim 1, The transmission matrix of the N-th retransmission signal is the same as the initial transmission signal, and the transmission matrix of the N + th primary retransmission signal is the same as the retransmission signal. (Wherein N is a natural number equal to or greater than 2). The method of claim 1, In step (b), The retransmission matrix

The number of transmit antennas of the transmitter is 2, the number of receive antennas of the receiver is N, the size of the space-time encoding block is T, and the initial transmission matrix is

Retransmission method of a multi-antenna transmitter. Where N and T are natural numbers,

Is a complex number

Complex complex, elements in row i and j

Is

And

Linear Combination of,

Is the symbol, q is the symbol index, and i is the number of the transmitting antenna) The method of claim 1, In step (b), The retransmission matrix is any one of the following first to third retransmission matrices, the number of transmitting antennas of the transmitting apparatus is 3, the number of receiving antennas of the receiving apparatus is N, the size of the space-time encoding block is T, and the initial stage. The transmission matrix is

Retransmission method of a multi-antenna transmitter. First retransmission matrix:

Second retransmission matrix:

Third retransmission matrix:

Where N and T are natural numbers,

Is a complex number

Complex complex, elements in row i and j

Is

And

Linear Combination of,

Is the symbol, q is the symbol index, and i is the number of the transmitting antenna) The method of claim 1, In step (b), The retransmission matrix

The number of transmit antennas of the transmitter is 4, the number of receive antennas of the receiver is N, the size of the space-time encoding block is T, and the initial transmission matrix is

Retransmission method of a multi-antenna transmitter. Where N and T are natural numbers,

Is a complex number

Complex complex, elements in row i and j

Is

And

Linear Combination of,

Is the symbol, q is the symbol index, and i is the number of the transmitting antenna.) The method of claim 4, wherein When an error is detected in the first retransmission signal, the N-th retransmission signal is encoded in the same form as the initial transmission matrix, and the N + 1st retransmission signal is sequentially transmitted from the first retransmission matrix to the first according to the number of retransmissions. A retransmission method of a multi-antenna transmitter for encoding in one of three retransmission matrices. (Wherein N is a natural number equal to or greater than 2). The method of claim 5, And reproducing a second retransmission signal and a third retransmission signal by encoding the second retransmission signal and the third retransmission matrix after the error is detected in the retransmission signal.

,

(From here,

Is the kth retransmission matrix.) A retransmission method of a multi-antenna transmitter for performing hybrid automatic retransmission in cooperation with a receiver, (a) encoding and transmitting a codeword transmitted to the receiver in the form of an initial transmission matrix, which is a linear distributed code, and receiving an error check result for the codeword from the receiver; And (b) if an error is detected in the codeword, add a first parity for error correction to the codeword, and then add the codeword or a portion of the codeword to a retransmission matrix, where the retransmission matrix is the initial transmission matrix. A linear distributed code comprising components and different from the initial transmission matrix and having the same capacity and diversity gain as the initial transmission matrix, wherein the first parity is in the form of the initial transmission matrix. Transmitting the first retransmission signal generated by encoding to the receiving device Retransmission method of a multi-antenna transmitter comprising a. The method of claim 8, If an error is detected in the first retransmission signal, after adding a second parity for error correction to the first parity, the first parity is encoded in the form of the retransmission matrix, and the second parity is the initial parity. A retransmission method of a multi-antenna transmitter for transmitting a second retransmission signal generated by encoding a transmission matrix to the receiver. The method of claim 9, Retransmission method of the third retransmission signal according to the detection of the error in the second retransmission signal is the same method as the generation of the second retransmission signal retransmission method of the multi-antenna transmission apparatus. A retransmission method of a multi-antenna transmitter for performing hybrid automatic retransmission in cooperation with a receiver, (a) encoding a codeword including an information word and an initial parity in the form of an initial transmission matrix, which is a linear distributed code, and transmitting the encoded codeword to the receiving apparatus, and receiving an error checking result for the codeword from the receiving apparatus; And (b) if an error is detected in the codeword, after adding a first parity for error correction to the information word, the information word is a retransmission matrix, where the retransmission matrix consists of components of the initial transmission matrix, A first order generated by encoding in the form of a linear distributed code that is different from the transmission matrix and has the same capacity and diversity gain as the initial transmission matrix, and wherein the first parity is encoded in the form of the initial transmission matrix Transmitting a retransmission signal to the receiving device Retransmission method of a multi-antenna transmitter comprising a. The method of claim 11, If an error is detected in the first retransmission signal, after adding a second parity for error correction to the information word, the information word is a second retransmission matrix, where the second retransmission matrix is configured of the initial transmission matrix. A linear distributed code consisting of elements different from the initial transmission matrix and having the same capacity and diversity gain as the initial transmission matrix, and encoding the second parity in the form of the initial transmission matrix. Retransmission method of a multi-antenna transmitter for transmitting a second retransmission signal generated by the reception device. The method of claim 12, If an error is detected in the second retransmission signal, after adding a third parity for error correction to the information word, the information word is a third retransmission matrix, where the third retransmission matrix is configured of the initial transmission matrix. A linear dispersion code consisting of elements and different from the initial transmission matrix and having the same capacity and diversity gain as the initial transmission matrix, and encoding the third parity in the form of the initial transmission matrix. Retransmission method of a multi-antenna transmitter for transmitting the third retransmission signal generated by the receiving device. The method of claim 13, The generation of the retransmission signal after the fourth as the error is detected in the third retransmission signal is the same method as the generation of the third retransmission signal retransmission method of the multi-antenna transmission apparatus. An error checking method of a multi-antenna receiver for performing hybrid automatic retransmission in cooperation with a transmitter, (a) performing an error check on the retransmitted signal retransmitted from the transmitting apparatus with respect to the initial transmitted signal; (b) if an error is detected in the retransmission signal, converting a first LLR vector generated by combining the initial transmission signal and the retransmission signal with a Log Likelihood Ratio (LLR) soft information into an information word; (c) detecting a channel fluctuation range of the initial transmission signal and the retransmission signal and comparing it with a preset reference value; And (d) performing an error check on the information word when the channel variation width exceeds the reference value The retransmission signal includes a component of an initial transmission matrix that encodes the initial transmission signal, but is different from the initial transmission matrix and is a linear distributed code having the same capacity and diversity gain as the initial transmission matrix. An error checking method of a multi-antenna receiver which is a signal encoded by a retransmission matrix. The method of claim 15, In step (b), The LLR soft combining generates an LLR vector composed of LLR values having a large absolute value by comparing the absolute value of the LLR in a plurality of bits or a plurality of symbols constituting each of the initial transmission signal and the retransmission signal. Error checking method of antenna receiver. The method of claim 15, As a result of the comparison in the step (c), if the channel variation width is equal to or less than the reference value, (A) performing space time code (STC) combining on the initial transmission signal and the retransmission signal; (B) elements composing the initial transmission matrix from the STC combining;

-here

Symbol

And

Performing a soft decision on the linear combination of the linear combination; (C) the symbols are compared with respect to a matrix composed of values obtained from the soft decision of step (b).

Generating a second LLR vector by calculating a soft decision on the symbols by applying inverse mapping of the linear combination to map to; And (D) selecting an LLR vector of the first LLR vector and the second LLR vector generated in step (b) and converting the information into an information word, and then performing an error check; Error checking method of the multi-antenna receiver further comprising. An error checking method of a multi-antenna receiver for performing hybrid automatic retransmission in cooperation with a transmitter, (a) performing an error check on the first retransmission signal retransmitted from the transmission device with respect to the initial transmission signal; (b) If an error is detected in the first retransmission signal, the first LLR vector and the first retransmission signal generated by LLR soft combining the initial transmission signal encoded in the form of a retransmission matrix and the initial transmission signal. Decoding the first parity for error correction included and converting the information into an information word; (c) detecting a channel fluctuation range of the initial transmission signal and the first retransmission signal and comparing the channel fluctuation with a preset reference value; And (d) performing an error check on the information word when the channel variation width exceeds the reference value The first retransmission signal includes a component of an initial transmission matrix that encodes the initial transmission signal, which is different from the initial transmission matrix and is linear having the same capacity and diversity gain as the initial transmission matrix. And a first parity for error correction encoded with the initial transmission matrix, to a signal encoded with a retransmission matrix that is a distributed code. The method of claim 18, In step (b), The LLR soft combining is performed by comparing the absolute values of the LLRs in the unit of a plurality of bits or symbols in the initial transmission signal encoded in the form of the retransmission matrix and each of the initial transmission signals to LLR values having a large absolute value. An error checking method of a multi-antenna receiver for generating a configured LLR vector. The method of claim 18, As a result of the comparison in the step (c), if the channel variation width is equal to or less than the reference value, (A) performing STC (Space Time Code) combining on the initial transmission signal encoded in the form of the retransmission matrix and the initial transmission signal; (B) elements composing the initial transmission matrix from the STC combining;

-here

Symbol

And

Performing a soft decision on the linear combination of the linear combination; (C) the symbols are compared with respect to a matrix composed of values obtained from the soft decision of step (b).

Generating a second LLR vector by calculating a soft decision on the symbols by applying inverse mapping of the linear combination to map to; And (D) selecting one LLR vector of the first LLR vector and the second LLR vector generated in step (b), decoding the first LLR vector together with the first parity, converting the information into an information word, and performing an error check on the information word. Steps to take Error checking method of the multi-antenna receiver further comprising. The method of claim 20, Error checking of the receiving device receiving the second retransmission signal, (e) the LLR vector selected in step (d) and the second retransmission signal, wherein the second retransmission signal is encoded in the form of the first parity and the initial transmission matrix encoded in the form of the retransmission matrix. Decoding a second parity together to convert to an information word, and performing an error check on the information word; (f) if an error is detected in the error checking of the step (e), the first parity encoded by the LLR soft combining the first parity encoded in the form of the initial transmission matrix and the retransmission matrix. 3 converting the LLR vector into an information word; (g) detecting a channel fluctuation range of the first retransmission signal and the second retransmission signal and comparing it with a preset reference value; And (h) performing an error check on the information word of step (f) if the channel variation width exceeds the reference value Error checking method of a multi-antenna receiver including a. The method of claim 21, As a result of the comparison in the step (g), if the channel fluctuation range is less than or equal to the reference value, (E) performing STC combining on the first parity encoded in the form of the initial transmission matrix and the first parity encoded in the form of the retransmission matrix; (E) elements constituting the transmission matrix of the first retransmission signal from the STC combining;

-here

Symbol

And

Performing a soft decision on the linear combination of the linear combination; (G) The symbols may be stored in a matrix composed of values obtained from the soft decision of step (f).

Generating a fourth LLR vector by calculating a soft decision on the symbols by applying inverse mapping of the linear combination to map to; And (H) select one LLR vector of the third LLR vector and the fourth LLR vector, decode the LLR vector and the second parity selected in the step (d) and convert the information into an information word; Steps to Perform Error Checking Error checking method of the multi-antenna receiver further comprising a An error checking method of a multi-antenna receiver for performing hybrid automatic retransmission in cooperation with a transmitter, (a) performing an error check on the first retransmission signal retransmitted from the transmitting apparatus with respect to the initial transmission signal including the information word and the initial parity; (b) if an error is detected in the first retransmission signal, converting the first LLR vector generated by LLR soft combining the information word of the first retransmission signal and the information word of the initial transmission signal into an information word; (c) detecting a channel fluctuation range of the initial transmission signal and the first retransmission signal and comparing the channel fluctuation with a preset reference value; (d) performing error checking by decoding the information word, the first parity for error correction included in the initial parity, and the first retransmission signal when the channel variability exceeds the reference value; The first retransmission signal includes a component of an initial transmission matrix for encoding the initial transmission signal, which is different from the initial transmission matrix, and has the same capacity and diversity gain as the initial transmission matrix. And a first parity for error correction encoded with the initial transmission matrix to an information word encoded with a primary retransmission matrix, which is a linear dispersion code. The method of claim 23, wherein In step (b), The LLR soft combining compares the absolute value of the LLR in a plurality of bit units or a plurality of symbol units constituting each information word encoded in the form of the first retransmission matrix and the information word encoded in the form of the initial transmission matrix. Error checking method of a multi-antenna receiver for generating an LLR vector composed of LLR values having a large absolute value. The method of claim 23, wherein As a result of the comparison in the step (c), if the channel variation width is equal to or less than the reference value, (A) performing space time code (STC) combining on the information words encoded in the form of the first retransmission matrix and the information words encoded in the form of the initial transmission matrix; (B) elements composing the initial transmission matrix from the STC combining;

-here

Symbol

And

Performing a soft decision on the linear combination of the linear combination; (C) the symbols are compared with respect to a matrix composed of values obtained from the soft decision of step (b).

Generating a second LLR vector by calculating a soft decision on the symbols by applying inverse mapping of the linear combination to map to; And (D) selecting an LLR vector of the first LLR vector and the second LLR vector generated in step (b) and decoding the initial LPT with the initial parity and the first parity to perform error checking; Error checking method of the multi-antenna receiver further comprising. The method of claim 25, Error checking of the receiving device receiving the second retransmission signal, (e) error checking by decoding a second retransmission signal, wherein the second retransmission signal includes an information word encoded in the form of a second retransmission matrix and a second parity encoded in the form of the initial transmission matrix. Performing a step; (f) a third LLR vector generated by LLR soft combining the information word encoded in the form of a second retransmission matrix and the LLR vector selected in step (d) if an error is detected in the error check of step (e). Converting the information word; (g) detecting a channel fluctuation range of the first retransmission signal and the second retransmission signal and comparing it with a preset reference value; And (h) if the channel variability exceeds the reference value, performing error checking by decoding the information word of the step (f) and the second parity together; Error checking method of a multi-antenna receiver including a. The method of claim 26, As a result of the comparison in the step (g), if the channel fluctuation range is less than or equal to the reference value, (E) performing STC combining on the information word encoded in the form of the second retransmission matrix and the LLR vector selected in the step (d); (E) elements constituting the primary retransmission signal from the STC combining;

-here

Symbol

And

Performing a soft decision on the linear combination of the linear combination; (G) The symbols may be stored in a matrix composed of values obtained from the soft decision of step (f).

Generating a fourth LLR vector by calculating a soft decision on the symbols by applying inverse mapping of the linear combination to map to; And (H) selecting an LLR vector of the third LLR vector and the fourth LLR vector, decoding the LLR vector together with the initial parity, the first parity, and the second parity to perform error checking; Error checking method of the multi-antenna receiver further comprising. The method according to any one of claims 17, 20, 22, 25 or 27, The channel matrix at the initial transmission

, The channel matrix at the first retransmission

Channel matrix

The (i, j) th element of

With the (i, j) th element of

If the average value of the (i, j) -th element of, STC combining is error checking method of a multi-antenna receiver as follows.

(Here, the channel matrix is a matrix having the (i, j) th element of the fading coefficient experienced by the signal received from the j th transmit antenna by the i th receive antenna,

,

Is the i th column vector of initial transmission matrix and retransmission matrix, respectively.

Is

The initial received signal sequence in the form of a column vector,

Is

The retransmitted received signal sequence in the form of a column vector corresponding to

,

Is the noise column vector added when the received signal is measured, i is

Is a natural number, T is the size of the space-time encoding block) The method according to any one of claims 17, 20, 22, 25 or 27, One selected LLR vector is, An error checking method of a multi-antenna receiver, which is an LLR vector having an average value of absolute values of LLRs per bit among the two LLR vectors, and having a small standard deviation of the absolute values of LLRs per bit. A multi-antenna transmitter for performing hybrid automatic retransmission in cooperation with a receiver, A channel encoder for generating a codeword by encoding the information word for transmission and the first parity for error correction together; And STC (Space Time Code) encoder for encoding the codeword into a linear distributed code to generate a retransmission signal having the same capacity and diversity gain as the initial transmission signal, and then transmits the retransmission signal to the receiver Wherein the retransmission signal comprises a component of an initial transmission matrix that encodes the initial transmission signal, wherein the retransmission signal is a first retransmission matrix that is different from the initial transmission matrix. The method of claim 30, The channel encoder generates a parity up to a predetermined maximum number of retransmissions for generating the retransmission signal when the initial transmission signal is generated. The method of claim 31, wherein If an error is detected in the retransmission signal, the STC encoder adds a second parity generated by the channel encoder to the first parity, and then encodes the first parity into the first retransmission matrix, wherein the second parity is encoded. And a parity is encoded by the initial transmission matrix. The method of claim 31, wherein The STC encoder adds the parity generated by the channel encoder to the information word, and then adds the information word to the N th retransmission matrix according to the number of times of retransmission signal, wherein the N th retransmission matrix is the first retransmission matrix. A linear variance code consisting of components of a matrix, different from the first retransmission matrix, and having the same capacity and diversity gain as the retransmission matrix, wherein the parity is set to the initial transmission matrix. Multi-antenna transmitter for encoding in the form. Where N is a natural number greater than or equal to 1. The method of claim 30, The STC encoder is configured to encode the odd-order retransmission signal transmitted to the receiver in the same form as the retransmission signal, and to encode the even-order retransmission signal in the same form as the initial transmission signal. A multi-antenna receiver for performing hybrid automatic retransmission in cooperation with a transmitter, An LLR calculator configured to generate an LLR vector using an initial transmission signal and the retransmission signal when an error is detected in the retransmission signal; A channel decoder for converting the LLR vector generated by the LLR calculator into an information word; And A cyclic redundancy check (CRC) check unit for performing an error check on the information word and transmitting a result of the error check to the transmitting device. Multiple antenna receiver comprising a. 36. The method of claim 35 wherein The LLR calculator compares an absolute value of the LLR in units of bits or symbols with respect to symbols constituting a repeated portion of the initial transmission signal and the retransmission signal, and includes a first LLR having a large absolute value of the LLR. A multi-antenna receiver for performing LLR soft combining to generate a vector. 36. The method of claim 35 wherein And a space time code (STC) decoder which senses a channel variation width of the initial transmission signal and the retransmission signal and compares it with a preset reference value. The method of claim 37, The channel fluctuation range sensed by the STC decoder is a difference between fading experienced while each of the initial transmission signal and the retransmission signal passes through a radio wave medium. 36. The method of claim 35 wherein The STC decoder transmits a second LLR vector generated by performing STC combining to remove fading and noise components from the initial transmission signal and the retransmission signal to the LLR calculator when the channel variation width is less than or equal to the reference value. Multi-antenna receiver. The method of claim 36 or 39, And the LLR calculator selects and transmits one LLR vector of the first LLR vector and the second LLR vector to the channel decoder. The method of claim 40, The LLR calculation unit compares the average value of the absolute value of the LLR per bit of the first LLR vector and the second LLR vector with the magnitude of the standard deviation of the absolute value of the LLR, the average value of the absolute value of the LLR per bit is large, And selecting one LLR vector having a small standard deviation of the LLRs per bit.

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