KR102184982B1 - Cooperative communication system with distributed space-time line codes for multi-relay node environments - Google Patents

Abstract

A collaborative communication system for transmitting data between a transmitting node and a receiving node via a relay node is disclosed. In the disclosed cooperative communication system, only relay nodes that successfully receive and decode data from a transmitting node among a plurality of relay nodes transmit data to the receiving node. Since relay nodes encode data using a space-time line encoding technique, a receiving device can receive data using a simple reception technique.

Description

Cooperative communication system using distributed space-time line coding in a multi-relay node environment {COOPERATIVE COMMUNICATION SYSTEM WITH DISTRIBUTED SPACE-TIME LINE CODES FOR MULTI-RELAY NODE ENVIRONMENTS}

The following embodiments relate to a cooperative communication system, specifically cooperative communication in which relay nodes that successfully receive data from a transmitting node transmit data to the receiving node using a space time line code (STLC). It is about the system.

A cooperative communication system in which multiple relay nodes exist between a transmitting node and a receiving node is known as a method capable of improving system performance by providing spatial diversity. In particular, it is known that the use of Maximum Ratio Transmission (MRT) in multiple relay nodes that successfully decode a packet arriving from a transmitting node obtains an optimal diversity effect. However, in order to implement MRT, the receiving node must acquire and calculate instantaneous radio channel information between the successfully decoded relay nodes and the receiving node to give feedback to the relay nodes that have succeeded in decoding every moment, which is a huge burden on system operation. Gives

The following embodiments aim to improve the performance of a cooperative communication system in which multiple relay nodes exist between a transmitting node and a receiving node.

The following embodiments aim to decode a received signal in a simple manner at a receiving node using a multi-antenna using space-time line codes.

According to an exemplary embodiment, a receiving unit for receiving data from a transmitting node, an encoding unit for space-time pre-encoding the received data, and a transmitting unit for transmitting the space-time pre-encoded data to a receiving node having a plurality of receiving antennas. A relay node containing is disclosed.

Here, the receiver may further include a determination unit for determining whether the received data is successfully decoded, and the transmission unit may transmit the space-time pre-coded data when the received data is successfully decoded.

And, from among the plurality of relay nodes that have received the data from the transmitting node, further comprising an estimating unit for estimating the number of relay nodes that have succeeded in decoding, the encoding unit in consideration of the number of relay nodes that have successfully decoded the The received data can be pre-coded in space-time.

In addition, the encoding unit may pre-encode the received data in space-time in consideration of a radio channel from the relay node to a reception antenna of the reception node.

Here, the encoding unit performs the space-time line encoding according to Equation 1 below,

[Equation 1]

는 상기 송신 노드로부터 상기 데이터를 수신한 복수의 중계 노드들 중에서 수신한 데이터를 성공적으로 복호한 중계 노드의 인덱스이고,

는 수신한 데이터를 성공적으로 복호한 k번째 중계 노드로부터 상기 수신 노드의 첫 번째 수신 안테나까지의 무선 채널을 나타내고,

는 수신한 데이터를 성공적으로 복호한 k번째 중계 노드로부터 상기 수신 노드의 두 번째 수신 안테나까지의 무선 채널을 나타낸다.

은 상기 송신 노드가 전송하여 상기 수신부가 수신한 제1 데이터 심볼이고,

는 상기 송신 노드가 전송하여 상기 수신부가 수신한 제2 데이터 심볼이다.here,

Is an index of a relay node that successfully decoded the received data among a plurality of relay nodes that received the data from the transmitting node,

Denotes a radio channel from the k-th relay node having successfully decoded the received data to the first receiving antenna of the receiving node,

Denotes a radio channel from the k-th relay node having successfully decoded the received data to the second receiving antenna of the receiving node.

Is a first data symbol transmitted by the transmitting node and received by the receiving unit,

Is a second data symbol transmitted by the transmitting node and received by the receiving unit.

은 상기 송신 노드로부터 상기 데이터를 수신한 복수의 중계 노드들 중에서, 상기 복호에 성공한 중계 노드의 개수를 나타낸다.

는 수신한 데이터를 성공적으로 복호한 k번째 중계 노드로부터 상기 수신 노드 사이의 무선 채널 벡터의 크기이다.

Denotes the number of relay nodes that successfully decoded from among a plurality of relay nodes that received the data from the transmitting node.

Is the size of a radio channel vector between the receiving node and the k-th relay node that successfully decodes the received data.

를 전송하고, 제2 시간 슬롯 동안에는 상기

를 전송할 수 있다.During the first time slot, the transmission unit

And, during the second time slot, the

Can be transmitted.

According to another exemplary embodiment, a transmission node that transmits data to a receiving node via at least one relay node, comprising a transmission unit that transmits data to a plurality of relay nodes, and transmits it to the plurality of relay nodes. The obtained data may be pre-coded in space-time at each relay node and transmitted to the receiving node.

Here, the data transmitted to the plurality of relay nodes may be transmitted to the receiving node only from relay nodes that have successfully decoded the data among the plurality of relay nodes.

In addition, among the plurality of relay nodes, the number of relay nodes that successfully decode the data is estimated, and the data transmitted to the plurality of relay nodes are space-time pre-coded in consideration of the number of relay nodes that successfully decode the data. I can.

In addition, data transmitted to the plurality of relay nodes may be pre-coded in space-time in consideration of a radio channel from the relay node to a reception antenna of the reception node.

According to another exemplary embodiment, in a receiving node having a plurality of receiving antennas, a receiving unit receiving space-time pre-coded data from a relay node that has received data from a transmitting node using each receiving antenna, and the receiving unit A receiving node including a decoding unit that decodes the space-time pre-coded data is disclosed.

Here, the receiving unit may receive the space-time pre-coded data only from relay nodes that have successfully decoded the received data among relay nodes that have received data from the transmitting node.

In addition, the space-time pre-coded data may be space-time pre-coded in consideration of the number of relay nodes that successfully decode the data among relay nodes that have received data from the transmitting node.

In addition, the space-time pre-coded data may be space-time pre-coded in consideration of a radio channel from the relay node to each of the reception antennas of the reception node.

Here, the decoding unit may decode the received space-time pre-coded data according to Equation 2 below.

[Equation 2]

은 상기 송신 노드가 전송한 제1 데이터 심볼이고,

는 상기 송신 노드가 전송한 제2 데이터 심볼이다.

는 제1 시간 슬롯 동안 제1 수신 안테나를 이용하여 수신한 신호이고,

는 제1 시간 슬롯 동안 제2 수신 안테나를 이용하여 수신한 신호이고,

는 제1 시간 슬롯 이후의 제2 시간 슬롯 동안 제1 수신 안테나를 이용하여 수신한 신호이고,

는 제2 시간 슬롯 동안 제2 수신 안테나를 이용하여 수신한 신호이다.here,

Is the first data symbol transmitted by the transmitting node,

Is a second data symbol transmitted by the transmitting node.

Is a signal received using the first receiving antenna during the first time slot,

Is a signal received using a second receiving antenna during a first time slot,

Is a signal received using the first receiving antenna during a second time slot after the first time slot,

Is a signal received using the second receiving antenna during the second time slot.

According to the following embodiments, the performance of a cooperative communication system in which multiple relay nodes exist between a transmitting node and a receiving node is improved.

According to the following embodiments, a reception node using a multi-antenna may decode a reception signal by a simple method using a space-time line code.

Fig. 1 is a diagram showing the concept of a cooperative communication system according to an exemplary embodiment.
Fig. 2 is a block diagram showing a structure of a transmitting node according to an exemplary embodiment.
Fig. 3 is a block diagram showing a structure of a relay node according to an exemplary embodiment.
Fig. 4 is a block diagram showing the structure of a receiving node according to an exemplary embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

Fig. 1 is a diagram showing the concept of a cooperative communication system according to an exemplary embodiment.

A cooperative communication system according to an exemplary embodiment includes a transmitting node 110, a plurality of relay nodes 120, 130, and 140, and a receiving node 150. In the embodiment shown in Fig. 1, the number of transmit antennas 111 of the transmitting node 110 is one. It is assumed that the relay nodes 120, 130, and 140 have one antenna 121, 131, and 141, and the receiving node 150 has a plurality of receiving antennas 151 and 152. Hereinafter, in the present specification, an embodiment in which the receiving node 150 includes two receiving antennas 151 and 152 will be described, but even when the number of receiving antennas 151 and 152 of the receiving node 150 is larger The invention can be applied in a similar way.

및 제2 데이터 심볼

를 복수의 중계 노드들(120, 130, 140)로 전송한다. 송신 노드(110)의 송신 안테나(111)로부터 중계 노드들(120, 130, 140)의 안테나(121, 131, 141)까지의 무선 채널을

라고 할 수 있다. 여기서, k는 중계 노드(120, 130, 140)를 나타내는 인덱스이다.The cooperative communication system shown in FIG. 1 is a two hop half-duplex communication system using a space time line code (STLC). The transmitting node 110 is a first data symbol

And the second data symbol

Is transmitted to the plurality of relay nodes 120, 130, and 140. A radio channel from the transmission antenna 111 of the transmission node 110 to the antennas 121, 131, and 141 of the relay nodes 120, 130, 140

It can be said. Here, k is an index indicating the relay nodes 120, 130, and 140.

In this case, the signals received by the relay nodes 120, 130, and 140 from the transmission node 110 may be expressed as Equation 1 below.

[Equation 1]

는 k번째 중계 노드가 수신한 신호를 나타낸다.

는 송신 노드의 전송 전력이고,

는 k번째 중계 노드에서의 열 잡음으로, 분포

를 따른다고 가정할 수 있다.

는 데이터 심볼이다. 일측에 따르면, 중계 노드들(120, 130, 140)은 최대 T개의 데이터 심볼을 이용하여 시공간 선 부호화를 수행할 수 있다. 이하 본 명세서에서는 중계 노드들이 2개의 데이터 심볼을 이용하여 시공간 선 부호화를 수행하는 실시예를 설명한다. 그러나, 시공간 선 부호화에 이용되는 데이터 심볼의 개수가 더 많은 경우에도 본 발명은 유사한 방법으로 적용될 수 있다.here,

Represents a signal received by the k-th relay node.

Is the transmit power of the transmitting node,

Is the thermal noise at the k-th relay node, the distribution

Can be assumed to follow.

Is the data symbol. According to one side, the relay nodes 120, 130, and 140 may perform space-time pre-coding using up to T data symbols. Hereinafter, an embodiment in which relay nodes perform space-time pre-coding using two data symbols will be described in the present specification. However, even when the number of data symbols used for space-time pre-coding is larger, the present invention can be applied in a similar manner.

및 제2 데이터 심볼

를 수신하여 복호할 수 있다. 일측에 따르면, 제1 데이터 심볼

및 제2 데이터 심볼

의 복호에 성공한 중계 노드의 집합(

)는 하기 수학식 2와 같이 나타낼 수 있다.Among the plurality of relay nodes 120, 130, 140, only some of the relay nodes 120 and 130 are the first data symbols

And the second data symbol

Can be received and decoded. According to one side, the first data symbol

And the second data symbol

The set of relay nodes that successfully decoded (

) Can be expressed as in Equation 2 below.

[Equation 2]

은 송신 노드(110)에서 수신 노드(150)까지 요구되는 전송률을 의미한다. 도 1에 도시된 실시예와 같이 2 홉을 사용하는 통신 시스템은 듀티 사이클 동안 주파수 효율이 감소되는 것을 보상하기 위해 송신 노드(110)와 수신 노드(150)가 직접 통신하는 시스템보다 데이터 전송률을 두배 증가시켜야 한다.

는 송신 SNR을 의미한다.here,

Denotes a transmission rate required from the transmitting node 110 to the receiving node 150. As in the embodiment shown in FIG. 1, the communication system using two hops doubles the data rate compared to the system in which the transmitting node 110 and the receiving node 150 directly communicate to compensate for the decrease in frequency efficiency during the duty cycle Should increase.

Denotes the transmit SNR.

및 제2 데이터 심볼

을 이용하여 시공간 선 부호화를 수행한다. 이 경우에, 일부 중계 노드들(120, 130)은 자신(120, 130)으로부터 수신 노드(150)사이의 무선 채널을 알고 있다고 가정한다. 예를 들어, 일부 중계 노드들(120, 130)은 수신 노드(150)로부터 파일럿 신호를 수신하고, 수신 노드(150)로부터 일부 중계 노드들(120, 130) 사이의 무선 채널을 파악할 수 있다. 만약 시분할 이중화(TDD: Time Division Duplex) 시스템인 경우에, 상향 링크와 하향링크간의 동일성(channel reciprocity)로 인하여 중계 노드들(120, 130)은 자신(120, 130)으로부터 수신 노드(150)사이의 무선 채널을 알 수 있다.Some of the relay nodes 120 and 130 that receive and decode the data symbol are the first data symbol

And the second data symbol

Space-time line coding is performed using. In this case, it is assumed that some of the relay nodes 120 and 130 know the radio channel between themselves 120 and 130 and the receiving node 150. For example, some of the relay nodes 120 and 130 may receive a pilot signal from the reception node 150 and determine a radio channel between some of the relay nodes 120 and 130 from the reception node 150. In the case of a time division duplex (TDD) system, the relay nodes 120 and 130 are between themselves 120 and 130 and the receiving node 150 due to channel reciprocity between the uplink and the downlink. You can know the wireless channel of

및 제2 데이터 심볼

은 하기 수학식 3같이 부호화될 수 있다.When some of the relay nodes 120 and 130 perform space-time pre-coding, the first data symbol

And the second data symbol

Can be encoded as in Equation 3 below.

[Equation 3]

는 상기 송신 노드로부터 상기 데이터를 수신한 복수의 중계 노드들 중에서 수신한 데이터를 성공적으로 복호한 중계 노드의 인덱스이고,

는 수신한 데이터를 성공적으로 복호한 k번째 중계 노드로부터 상기 수신 노드의 첫 번째 수신 안테나까지의 무선 채널을 나타내고,

는 수신한 데이터를 성공적으로 복호한 k번째 중계 노드로부터 상기 수신 노드의 두 번째 수신 안테나까지의 무선 채널을 나타낸다.

은 상기 송신 노드가 전송하여 상기 수신부가 수신한 제1 데이터 심볼이고,

는 상기 송신 노드가 전송하여 상기 수신부가 수신한 제2 데이터 심볼이다.here,

Is an index of a relay node that successfully decoded the received data among a plurality of relay nodes that received the data from the transmitting node,

Denotes a radio channel from the k-th relay node having successfully decoded the received data to the first receiving antenna of the receiving node,

Denotes a radio channel from the k-th relay node having successfully decoded the received data to the second receiving antenna of the receiving node.

Is a first data symbol transmitted by the transmitting node and received by the receiving unit,

Is a second data symbol transmitted by the transmitting node and received by the receiving unit.

은 상기 송신 노드로부터 상기 데이터를 수신한 복수의 중계 노드들 중에서, 상기 복호에 성공한 중계 노드의 개수를 나타낸다.

는 수신한 데이터를 성공적으로 복호한 k번째 중계 노드로부터 상기 수신 노드 사이의 무선 채널 벡터의 크기이다.

Denotes the number of relay nodes that successfully decoded from among a plurality of relay nodes that received the data from the transmitting node.

Is the size of a radio channel vector between the receiving node and the k-th relay node that successfully decodes the received data.

According to one side, some of the relay nodes 120 and 130 may estimate the number of relay nodes successfully decoded as shown in Equation 4 below.

[Equation 4]

는 복호에 성공한 중계 노드 집합에 속하는 원소의 개수를 나타내고,

은 중계 노드들이 사용하는 전체 전력을 나타낸다.

는 i번째 시간 슬롯에서 수신 노드(150)의 j번째 번째 수신 안테나에서 발생한 잡음으로,

를 따른다고 가정한다.here,

Represents the number of elements belonging to the set of relay nodes that successfully decoded,

Represents the total power used by the relay nodes.

Is the noise generated by the j-th receiving antenna of the receiving node 150 in the i-th time slot,

Is assumed to follow.

를 전송하고, 제2 시간 슬롯 동안에는 상기

를 전송할 수 있다.According to one side, some relay nodes 120 and 130 may be transmitted using two time slots. For example, the k-th relay node among some relay nodes 120 and 130 is the

And, during the second time slot, the

Can be transmitted.

The receiving node 150 receives signals during a plurality of slots using a plurality of receiving antennas 151 and 152. When the receiving node 150 uses two receiving antennas 151 and space-time pre-coded data symbols are transmitted during two time slots, the signal received by the receiving node 150 during two time slots is calculated as follows: It can be expressed as Equation 5.

[Equation 5]

는 i번째 시간 슬롯동안에 j번째 수신 안테나를 이용하여 수신한 수신 신호이고,

는 k번째 중계 노드와 수신 노드 사이의 무선 채널 벡터이고, 모든 채널은

분포를 따른다.here,

Is the received signal received using the j-th receiving antenna during the i-th time slot,

Is the radio channel vector between the k-th relay node and the receiving node, and all channels are

Follow the distribution

In this case, the receiving node 150 may decode the space-time pre-coded data by combining four received signals received during two time slots as shown in Equation 6 below.

[Equation 6]

는 복호된 제1 데이터 심볼이고,

는 복호된 제2 데이터 심볼이다.here,

Is the decoded first data symbol,

Is the decoded second data symbol.

Fig. 2 is a block diagram showing a structure of a transmitting node according to an exemplary embodiment.

The transmission node 200 according to an exemplary embodiment may include a transmission unit 210 and a transmission antenna 211. The transmitting node 200 shown in FIG. 2 transmits data to the receiving node 250 via at least one relay node 220, 230, and 240.

및 제2 데이터 심볼

를 복수의 중계 노드(220,230, 240)로 전송할 수 있다.The transmission unit 210 transmits data to a plurality of relay nodes 220, 230, and 240. According to one side, the transmission unit 210 is a first data symbol

And the second data symbol

May be transmitted to a plurality of relay nodes 220, 230, and 240.

및 제2 데이터 심볼

을 성공적으로 수신하여 복호할 수 있다.Among the plurality of relay nodes 220, 230, 240, only some of the relay nodes 220 and 230 are the first data symbol

And the second data symbol

Can be successfully received and decoded.

According to one side, some of the relay nodes 220 and 230 that successfully decode the received data may transmit the data received from the transmitting node 200 to the receiving node 250.

According to one side, some of the relay nodes 220 and 230 that successfully decode the received data are radio channels from some of the relay nodes 220 and 230 to the reception antennas 251 and 252 of the reception node 250 The received data may be pre-coded in space-time in consideration of and transmitted to the receiving antennas 251 and 252 of the receiving node 250.

및 제2 데이터 심볼

을 시공간 선 부호화하고, 시공간 선 부호화된 데이터 심볼들을 수신 노드(250)로 전송할 수 있다.According to one side, some relay nodes 220 and 230 are the first data symbol according to Equation 3

And the second data symbol

The space-time pre-coded is performed and the space-time pre-coded data symbols may be transmitted to the receiving node 250.

According to one side, some of the relay nodes 220 and 230 may estimate the number of relay nodes that successfully decode data, and perform space-time pre-coding in consideration of the number of relay nodes that successfully decode data.

According to one side, some of the relay nodes 220 and 230 are space-time lines in consideration of the radio channels from the antennas 221 and 231 of the relay nodes 220 and 230 to the reception antennas 251 and 252 of the receiving node 250 Can be coded.

Fig. 3 is a block diagram showing a structure of a relay node according to an exemplary embodiment.

The relay node 300 according to an exemplary embodiment may include an antenna 351, a receiving unit 310, a determining unit 320, an estimating unit 330, an encoding unit 340, and a transmitting unit 350. .

및 제2 데이터 심볼

를 수신할 수 있다.The receiving unit 310 receives data from the transmitting node 360 using the antenna 351. According to one side, the receiving unit 310 is a first data symbol from the transmitting node 360

And the second data symbol

Can receive.

The determination unit 320 determines whether the data received by the reception unit 310 has been successfully decoded. According to one side, the data received by the receiving unit 310 may not be successfully decoded. In this case, the estimating unit 330, the encoding unit 340, and the transmitting unit 350 may wait without performing an operation for transmitting the received data to the receiving node 360. According to another aspect, the data received by the receiving unit 310 may be successfully decoded. In this case, the estimation unit 330, the encoding unit 340, and the transmission unit 350 may perform an operation for transmitting the received data to the reception node 360. Hereinafter, operations of the estimation unit 330, the encoding unit 340, and the transmission unit 350 will be described on the assumption that data received by the receiving unit 310 is successfully decoded.

The estimation unit 330 estimates the number of relay nodes that have successfully decoded data from among a plurality of relay nodes that have received data from the transmission node 360. According to one side, the estimating unit 330 may estimate the number of relay nodes that successfully decoded data according to Equation 4.

The encoder 340 pre-encodes the received data. According to one side, the encoding unit 340 may pre-encode the received data in consideration of a radio channel from the antenna 351 of the relay node 300 to the reception antennas 361 and 362 of the receiving node 360. have. In addition, the encoder 340 may pre-encode the received data in consideration of the number of relay nodes successfully decoded. According to one side, the encoder 340 may perform encoding according to Equation (3).

When the received data is successfully decoded, the transmission unit 350 transmits the space-time pre-coded data to the receiving node 360. The receiving node 360 may include a plurality of receiving antennas 361 and 362. According to one side, the transmission unit 350 may transmit data encoded according to Equation 3 to the reception node 360 during a plurality of time slots.

Fig. 4 is a block diagram showing the structure of a receiving node according to an exemplary embodiment.

The receiving node 400 according to an exemplary embodiment includes a plurality of receiving antennas 421 and 422, a receiving unit 410, and a decoding unit 420.

The receiving unit 410 receives space-time pre-coded data from the relay nodes 430 and 440 using a plurality of receiving antennas 421 and 422. According to one side, each of the relay nodes 430, 440, and 450 receives data from a transmitting node (not shown), but only some of the relay nodes 430 and 440 can successfully decode the data. In this case, only some of the relay nodes 430 and 440 that successfully decode the data may transmit the received data to the receiving node 400.

According to one side, the space-time pre-encoded data received by the receiver 410 is space-time pre-encoded in consideration of the number of relay nodes 430 and 440 that have successfully decoded the data among the plurality of relay nodes 430, 440, and 450. It may have been.

According to one side, the space-time pre-coded data received by the receiving unit 410 is from the antennas 431 and 441 of the relay nodes 430 and 440 that successfully decode the data and the receiving antennas 421 and 422 of the receiving node 400 It may be space-time pre-coded in consideration of radio channels up to.

를 수신하고, 제2 시간 슬롯 동안에는

를 수신할 수 있다.According to one side, the space-time pre-coded data received by the receiving unit 410 may be space-time pre-coded data according to Equation (3). In this case, the receiving unit 410 of the k-th relay node during the first time slot

Receive, and during the second time slot

Can receive.

According to one side, the space-time pre-coded data received by the receiver 410 may be space-time pre-coded data according to Equation (3). The received signal received by the receiver 410 may be expressed as Equation (5).

The decoder 420 may decode the received space-time pre-coded data. When the data received by the receiver 410 is encoded according to Equation 3, the decoding unit 420 may decode the space-time pre-coded data according to Equation 6.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like alone or in combination. The program instructions recorded on the medium may be specially designed and configured for the embodiment, or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -A hardware device specially configured to store and execute program instructions such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of the program instructions include not only machine language codes such as those produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as one or more software modules to perform the operation of the embodiment, and vice versa.

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.

200: sending node
210: transmission unit
211: transmitting antenna
220, 230, 240: relay node
221, 231, 231: antenna
222, 232, 242, 223, 224, 233, 234, 243, 244: Wireless channel
250: receiving node
251, 252: receiving antenna

Claims (14)

A receiving unit for receiving data from a transmitting node;
An encoding unit for pre-coding the received data in space-time;
A transmission unit for transmitting the space-time pre-coded data to a reception node having a plurality of reception antennas;
A determination unit determining whether the data received by the receiver is successfully decoded; And
An estimating unit for estimating the number of relay nodes that successfully decoded the received data from among a plurality of relay nodes that received the data from the transmitting node
Including,
The encoding unit performs space-time pre-coding of the received data in consideration of the number of relay nodes that have succeeded in decoding
The transmission unit transmits the space-time encoded data when the received data is successfully decoded. delete delete The method of claim 1, wherein the encoding unit
A relay node for space-time pre-coding of the received data in consideration of a radio channel from the relay node to a reception antenna of the reception node. The method of claim 1, wherein the encoding unit
The space-time line coding is performed according to Equation 1 below,

[Equation 1]

here,

Is an index of a relay node that successfully decoded the received data among a plurality of relay nodes that received the data from the transmitting node,

Denotes a radio channel from the k-th relay node having successfully decoded the received data to the first receiving antenna of the receiving node,

Denotes a radio channel from the k-th relay node having successfully decoded the received data to the second receiving antenna of the receiving node.

Is a first data symbol transmitted by the transmitting node and received by the receiving unit,

Is a second data symbol transmitted by the transmitting node and received by the receiving unit.

Denotes the number of relay nodes that successfully decoded from among a plurality of relay nodes that received the data from the transmitting node.

Is the size of a radio channel vector between the receiving node and the k-th relay node that successfully decodes the received data.
The transmission unit
During the first time slot, the

And, during the second time slot, the

Relay node that transmits. In a transmitting node that transmits data to a receiving node via at least one relay node,
Transmission unit that transmits data to multiple relay nodes
Including,
The number of relay nodes that successfully decoded the data among the plurality of relay nodes is estimated,
The transmission node in which the data transmitted to the plurality of relay nodes is pre-coded in space-time in consideration of the number of relay nodes that successfully decode the data. The method of claim 6,
The data transmitted to the plurality of relay nodes is transmitted to the receiving node only from relay nodes that have successfully decoded the data among the plurality of relay nodes. delete The method of claim 6,
The data transmitted to the plurality of relay nodes is space-time pre-coded in consideration of a radio channel from the relay node to a reception antenna of the reception node. In a receiving node having a plurality of receiving antennas,
A receiving unit for receiving space-time pre-coded data from a relay node that has received data from a transmitting node using each of the receiving antennas; And
A decoder that decodes the received space-time pre-coded data
Including,
The space-time pre-coded data is space-time pre-coded in consideration of the number of relay nodes that have successfully decoded the data among relay nodes that have received data from the transmitting node. The method of claim 10,
The receiving unit receives the space-time pre-coded data only from relay nodes that have successfully decoded the received data from among relay nodes that have received data from the transmitting node. delete The method of claim 10, wherein the space-time pre-coded data,
A receiving node that is space-time pre-coded in consideration of a radio channel from the relay node to each of the receiving antennas of the receiving node. The method of claim 10,
The receiving node decodes the received space-time pre-coded data according to Equation 2 below.

[Equation 2]

here,

Is the first data symbol transmitted by the transmitting node,

Is a second data symbol transmitted by the transmitting node.

Is a signal received using the first receiving antenna during the first time slot,

Is a signal received using a second receiving antenna during the first time slot,

Is a signal received using the first receiving antenna during the second time slot,

Is a signal received using the second receiving antenna during the second time slot.

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