KR101386974B1 - Method of allocating wireless resource for space division multiple access communication and wireless resource allocation system of enabling the method - Google Patents

Abstract

A radio resource allocation system for space division multiple access communication is disclosed. A radio resource allocation system for spatial division multiple access communication includes a channel state recognizer for recognizing channel states of radio channels formed between neighboring nodes including a source node, a relay node, and a target node, and the target node according to the channel state. And a radio resource allocator configured to control at least one of a capacity of channel state information fed back from the source node or a relay level of the relay signal to which the source signal transmitted from the source node is relayed.

Space Division Multiple Access, SDMA, Multiple Antennas, Relay, MIMO, Cooperative Communications

Description

TECHNICAL FIELD OF ALLOCATING WIRELESS RESOURCE FOR SPACE DIVISION MULTIPLE ACCESS COMMUNICATION AND WIRELESS RESOURCE ALLOCATION SYSTEM OF ENABLING THE METHOD}

The present invention relates to a space division multiple access technique for transmitting a signal using a plurality of antennas, and more particularly, to construct an optimized space division multiple access communication environment by applying an additional technique to a beamforming technique for space division multiple access. A radio resource allocation system and method thereof for space division multiple access communication.

Recently, active researches are being conducted to provide various multimedia services including voice services and to support high quality and high speed data transmission in a wireless communication environment. As part of this research, technologies for MIMO (multiple input multiple output) systems using channels in the spatial domain are rapidly developing.

Many people require high speed wireless communication services, but there are many problems in providing or using high speed wireless communication services in a wireless communication environment. In particular, in a communication environment using a wireless channel, there is a limit in increasing the data rate due to the presence of multipath fading, selective frequency fading, and various communication obstacles. In order to overcome these limitations, representative techniques that have been proposed are multi-antenna-related and signal relay technologies.

Multi-antenna technology is a technology that increases the reliability of signal transmission and obtain a high data rate by transmitting a signal using a plurality of antennas. Furthermore, a space diversity technique of transmitting a signal through a plurality of antennas may increase reliability of a received signal. In particular, a technique of transmitting different signals to multiple users through a plurality of antennas is referred to as a space division multiple access (SDMA) technique. Space division multiple access technology increases the overall system capacity by using radio resources more efficiently.

Signals transmitted through a plurality of antennas using a spatial division multiple access technique are beam-formed through a precoding technique according to the radio channel state. That is, by properly precoding the data stream in accordance with the radio channel conditions, interference occurring between the radio channels can be reduced. For example, the base station provided with a plurality of antennas receives the channel state information on the radio channel formed between the mobile terminal and the base station from the mobile terminal and performs beamforming appropriately using the fed back channel state information. However, as will be described below, the radio resources are consumed in order for the base station to receive the channel state information.

In addition, the signal relaying technique is a technique for relaying a signal generated from the source node to the destination node through a relay node existing between the source node and the destination node. As a representative relay technique, the power amplification relay technique improves the signal to interference and noise ratio or data rate by the relay node amplifying the power of the source signal and transmitting it to the target node. . However, even in this case, radio resources are consumed by the relay node to relay signals.

However, until now, the beamforming technique and the signal relay technique for space division multiple access have been studied as separate techniques, and thus there is a problem that radio resources cannot be efficiently used. For example, when the channel state of the radio channel formed between the source node and the destination node is good, a good data rate and SINR can be obtained through proper beamforming even if the relay node is not necessarily used. However, in this case it may be inefficient to consume a lot of radio resources for signal relaying.

In addition, when the relay node and the target node are located very close together so that the desired data rate and SINR can be achieved with only a slight signal amplification, the source node feeds back a large amount of channel state information from the target node for beamforming. Although the need to receive is reduced, increasing the feedback capacity for channel state information may be a waste of radio resources.

Accordingly, a radio resource allocation system for space-division multiple access communication, which can reduce the waste of radio resources and achieve better performance by efficiently controlling the two techniques while simultaneously using a signal relay technique and a beam forming technique, and its Method is required.

The present invention provides a radio resource allocation system and method for space division multiple access communication that can achieve a higher data rate and SINR by transmitting / receiving data by mixing a space division multiple access technique and a signal relay technique.

In addition, the present invention determines the radio resources required for beamforming and the radio resources required for signal relay in consideration of the channel state of radio channels formed between neighboring nodes, thereby enabling the spatial division multiple access to more efficiently allocate radio resources. A radio resource allocation system and method for communication are provided.

In addition, the present invention provides a radio resource allocation system and method for space division multiple access communication that can achieve a higher data rate and SINR by properly allocating radio resources for beamforming and radio resources for signal relay. to provide.

The present invention also provides a radio resource allocation system and method for space division multiple access communication that can efficiently use radio resources by appropriately adjusting the capacity of the channel state information fed back by the target node.

In addition, the present invention provides a system and method for allocating a radio resource for space division multiple access communication that can efficiently allocate radio resources to reduce the hardware burden of the mobile terminal and save power.

A radio resource allocation system for spatial division multiple access communication according to an embodiment of the present invention includes a channel state recognition unit for recognizing channel states of radio channels formed between neighboring nodes including a source node, a relay node, and a destination node; And a radio resource allocator configured to control at least one of a capacity of channel state information fed back from the destination node to the source node or a relay level of a relay signal to which a source signal transmitted from the source node is relayed according to the channel state.

In this case, the radio resource allocator may control at least one of the capacity of the channel state information or the relay level in consideration of the ratio of the relay level to the capacity of the channel state information according to the channel state.

In this case, the radio resource allocator controls the relay level in consideration of the fixed capacity of the channel state information when the capacity of the channel state information is fixed, and the fixed relay level when the relay level is fixed. In consideration of this, the capacity of the channel state information can be controlled.

At this time, the radio resource allocation system for spatial division multiple access communication may further include a control information transfer unit for transmitting the control information related to the capacity or the relay level of the controlled channel state information to the neighboring nodes.

In this case, the source node may generate the source signal by beamforming a data stream using the channel state information fed back from the destination node according to the capacity of the channel state information.

In this case, the relay node may generate the relay signal in which the source signal is relayed according to the controlled relay level.

In this case, the destination node may feed back the channel state information to the source node according to the controlled capacity of the channel state information. In this case, the destination node may detect the relay signal according to the source signal and the relay level generated by beamforming the data stream.

The present invention can provide a radio resource allocation system and method for space division multiple access communication that achieves a higher data rate and SINR by transmitting / receiving data by mixing a signal relay technique with a multiple input / output technique.

In addition, the present invention determines the radio resources required for beamforming and the radio resources required for signal relay in consideration of the channel state of radio channels formed between neighboring nodes, thereby more efficiently allocating radio resources. A radio resource allocation system and a method thereof can be provided.

The present invention also provides a radio resource allocation system and method for space division multiple access communication that achieves higher data rate and SINR by appropriately allocating radio resources for beamforming and radio resources for signal relay. Can be.

In addition, the present invention can provide a radio resource allocation system and method for space division multiple access communication that efficiently allocates radio resources to reduce hardware burden and save power of a mobile terminal.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a space division multiple access communication network according to an embodiment of the present invention.

Referring to FIG. 1, a space division multiple access communication network according to an embodiment of the present invention includes a source node 110, a relay node 120, and a destination node 130.

The source node 110 may be a base station, and the relay node 120 and the destination node 130 may be mobile terminals. In particular, the relay node 120 may be a mobile terminal, it may be a relay. When the relay node 120 is a mobile terminal, the relay node 120 may receive a source signal transmitted from the source node 110 and decode the source signal.

The source node 110 may be provided with a plurality of antennas, and the source node 110 may transmit / receive a signal through the plurality of antennas. In addition, wireless channels are formed between neighboring nodes including the source node 110, the relay node 120, and the destination node 130.

이 형성되고, 소스 노드(110)과 목적 노드(130) 사이에는 무선 채널

이, 중계 노드(120)와 목적 노드(130) 사이에는 무선 채널

이 형성된다. That is, the radio channel between the source node 110 and the relay node 120

Is formed, and a wireless channel between the source node 110 and the destination node 130

The radio channel is between the relay node 120 and the destination node 130.

.

When the source node 110 intends to transmit the data stream s to the destination node 130, the data node s may be beamformed using a spatial division multiple access (SDMA) technique. In particular, the source node 110 may beamform the data stream s in Space Division Access Multiplexing (SDMA). That is, the source node 110 transmits a source signal generated by multiplying the spatially separated beamforming vector and the data stream s to the destination node 130, thereby minimizing interference that may occur between radio channels. have.

와 중계 노드(120)와 형성된 무선 채널

의 상태를 파악하고, 파악된 무선 채널들을 이용하여 적절한 빔 포밍 벡터를 선택할 수 있다.However, in order for the source node 110 to generate a source signal, a wireless channel formed with the destination node 130 is provided.

And a wireless channel formed with the relay node 120

It is possible to determine the state of and to select an appropriate beamforming vector using the identified wireless channels.

및

의 상태를 파악할 수 있다. 이 때, 채널 상태 정보는 채널 방향 정보(Channel Direction Information, CDI) 또는 채널 품질 정보(Channel Quality Information)를 포함할 수 있다. The source node 110 receives the channel status information (CSI) from the destination node 130 and the relay node 120 to provide a wireless channel.

And

I can grasp the state of the. In this case, the channel state information may include channel direction information (CDI) or channel quality information.

및

를 추정할 수 있다. 이 때, 목적 노드(130) 및 중계 노드(120)는 추정된

및

와 관련된 정보를 채널 상태 정보로서 소스 노드(110)로 피드백할 수 있다.For example, the source node 110 transmits a pilot signal and the like, and the destination node 130 and the relay node 120 transmit the pilot signal and the like to the radio channel.

And

Can be estimated. At this time, the destination node 130 and the relay node 120 is estimated

And

Information related to the feedback may be fed back to the source node 110 as channel state information.

However, the channel state information is quantized and transmitted from the destination node 130 and the relay node 120 to the source node 110. The radio channel corresponding to the quantized channel state information (CSI) is an actual radio channel. Can be different from.

If the quantization level is high (the capacity of the channel state information is large), the destination node 130 and the relay node 120 may feed back more accurate channel state information (CSI) to the source node 110, High quantization levels may cause excessive consumption of radio resources by increasing the capacity of channel state information (CSI).

As a result, the higher the quantization level, the more accurate channel state information (CSI) is fed back to the source node 110, so that the source node 110 can improve the effect of beamforming by selecting a more accurate beamforming vector. However, there is a disadvantage in that the capacity of the feedback channel state information (CSI) becomes large. Therefore, it is good to control the quantization level appropriately and obtain an effect according to beamforming without excessively increasing the capacity of the channel state information (CSI) fed back.

In addition, the relay node 120 receives the source signal from the source node 110, generates a relay signal and transmits to the destination node 130. In this case, the relay node 120 may be a repeater or a mobile terminal.

Various radio resources are also consumed by the relay node 120 to transmit the relay signal to the destination node 130. For example, the power of the relay signal, the frequency band of the relay signal, the relay time of the relay signal, and the like may be consumed as a radio resource. The relay node 120 determines the relay level related to the power of the relay signal, the frequency band of the relay signal, the relay time of the relay signal, and the like, and generates the relay signal according to the determined relay level. For example, the relay level may be set high so that the power of the relay signal and the relay time of the relay signal increase.

의 상태가 양호하고, 중계 노드(120)와 목적 노드(130) 사이에 형성된 무선 채널

의 상태가 불량한 경우 중계 신호를 송신하는 데 많은 무선 자원을 소모하는 것은 비효율적일 수 있다. 즉, 적절한 빔 포밍만으로도 양호한 데이터 전송률 또는 SINR을 얻을 수 있다면, 채널 상태 정보의 용량을 증가시키는 반면, 중계 신호의 생성을 위한 무선 자원을 절약하는 것이 효율적일 수 있다. However, since various radio resources are consumed even when the relay node 120 transmits the relay signal, appropriate control is required. For example, a wireless channel formed between source node 110 and destination node 130.

Is in a good condition, and the radio channel formed between the relay node 120 and the destination node 130

In the case of poor state, it may be inefficient to consume a lot of radio resources for transmitting the relay signal. That is, if a good data rate or SINR can be obtained only by proper beamforming, it may be efficient to increase the capacity of the channel state information while saving radio resources for generating the relay signal.

2 is a block diagram illustrating a radio resource allocation system for spatial division multiple access communication according to an embodiment of the present invention.

2, a radio resource allocation system for spatial division multiple access communication according to an embodiment of the present invention may include a channel state recognizer 210, a radio resource assigner 220, and a control information transmitter 230. Include.

In this case, the radio resource allocation system for the space division multiple access communication of the present invention may be installed in a separate node as well as a source node, a relay node and a destination node.

The channel state recognizer 210 recognizes channel states of radio channels formed between neighboring nodes including a source node, a relay node, and a destination node.

In this case, the channel state recognizer 210 may recognize channel states of wireless channels formed between neighboring nodes through various methods. In this case, the channel state recognizer 210 may recognize channel states of wireless channels formed between neighboring nodes by using various channel estimation techniques. In addition, the channel state recognizer 210 may not only estimate channel states of the wireless channels by itself, but also receive channel information estimated from at least one adjacent node to recognize channel states of the wireless channels. .

For example, suppose that a radio resource allocation system for space division multiple access communication of the present invention is installed in a relay node.

If the source node broadcasts the pilot signal, the channel state recognition unit 210 installed in the relay node may recognize the channel state by estimating the channel state of the wireless channel formed with the source node.

The channel state recognizer 210 installed in the relay node may estimate the channel state of the wireless channel without performing channel estimation by itself. That is, the relay node may transmit a pilot signal to the destination node, and the destination node may estimate a channel state of a wireless channel formed between the destination node and the relay node through the pilot signal. In this case, the destination node may feed back information related to the estimated channel state to the relay node, and the channel state recognizer 210 may recognize the channel state without performing channel estimation by itself.

) 또는 소스 노드로부터 송신된 소스 신호가 중계된 중계 신호의 중계 레벨(

) 중 적어도 하나를 제어한다.In addition, the radio resource allocator 220 may store the capacity of the channel state information fed back from the target node to the source node according to the channel state.

) Or the relay level of the relay signal at which the source signal sent from the source node was relayed (

Control at least one of

)이 클수록 더욱 정확한 빔 포밍 벡터가 선택될 수 있고, 정확한 빔 포밍 벡터를 이용하여 빔 포밍된 소스 신호는 목적 노드로 높은 데이터 전송률로 전송될 수 있다.That is, the source node generates a source signal by beamforming the data stream using the beamforming vector. At this time, the capacity of the channel state information fed back from the target node to the source node (

The larger the), the more accurate beamforming vector can be selected, and the source signal beamformed using the correct beamforming vector can be transmitted at a high data rate to the destination node.

)은 중계 신호의 파워, 중계 신호의 주파수 대역, 중계 신호의 중계 시간 등과 관련 것이다. 예를 들어, 중계 레벨(

)이 높게 제어되었다면 중계 신호의 파워가 높거나, 중계 시간이 긴 것으로 볼 수 있다.In addition, the relay level of the relay signal (

) Is related to the power of the relay signal, the frequency band of the relay signal, the relay time of the relay signal, and the like. For example, the relay level (

If the control is high, the relay signal has a high power or a long relay time.

As a result, the present invention can more efficiently use radio resources by controlling radio resources consumed for beamforming and radio resources consumed for signal relay.

)이 특정한 값인 X로 고정된 경우, X를 고려하여 중계 레벨(

)을 제어하고, 중계 레벨(

)이 특정한 값인 Y로 고정된 경우, Y를 고려하여 채널 상태 정보의 용량(

)을 제어할 수 있다.At this time, the radio resource allocator 220 stores the capacity of the channel state information.

) Is fixed to a specific value of X, the relay level (

), And the relay level (

) Is fixed to a specific value of Y, the capacity of the channel state information (

) Can be controlled.

)이 Y로 고정된 경우를 가정한다. 이 때, 무선 자원 할당부(220)는 소스 노드와 목적 노드 사이에 형성된 무선 채널의 채널 상태를 고려하여 채널 상태 정보의 용량(

)을 제어할 수 있다. 즉, 소스 노드와 목적 노드 사이에 형성된 무선 채널의 채널 상태가 좋아, 채널 상태 정보의 용량(

)이 커지면 빔 포밍에 따른 성능 향상이 클 것으로 예측되는 경우, 무선 자원 할당부(220)는 채널 상태 정보의 용량(

)을 증가시킬 수 있다.For example, a radio resource allocation system for space division multiple access communication according to the present invention is installed in a source node, and a relay level (

Assume that) is fixed to Y. In this case, the radio resource allocator 220 may determine the capacity of the channel state information in consideration of the channel state of the radio channel formed between the source node and the target node.

) Can be controlled. That is, the channel state of the radio channel formed between the source node and the target node is good, so that the capacity of the channel state information (

If it is expected that the increase in performance due to beamforming is large, the radio resource allocator 220 may determine the capacity of the channel state information.

) Can be increased.

)에 대한 중계 레벨(

)의 비율을 고려하여 채널 상태 정보의 용량 또는 중계 레벨 중 적어도 하나를 제어할 수 있다.At this time, the radio resource allocator 220 stores the capacity of the channel state information.

Relay level for

At least one of the capacity or the relay level of the channel state information may be controlled in consideration of the ratio of.

)에 대한 중계 레벨(

)의 비 율을 고려할 수 있다.That is, in general, since the radio resources available in the communication system are limited, the radio resource allocator 220 may determine the capacity of the channel state information.

Relay level for

The ratio of) can be considered.

)이 높을수록 경우 중계 레벨(

)이 감소하고, 중계 레벨(

)이 높을수록 상기 채널 상태 정보의 용량(

)이 감소하도록 채널 상태 정보의 용량(

) 또는 중계 레벨(

) 중 적어도 하나를 제어할 수 있다.For example, the radio resource allocator 220 may store the capacity of the channel state information.

), The higher the relay level (

) Decreases, and the relay level (

Is higher, the capacity of the channel state information (

Volume of channel state information so that

) Or relay level (

Control at least one of

) 또는 중계 레벨(

) 중 적어도 하나를 제어할 수 있다.At this time, the radio resource allocator 220 compares the channel state of the first radio channel formed between the source node and the target node and the channel state of the second radio channel formed between the relay node and the target node and compares the channel state information. Volume(

) Or relay level (

Control at least one of

)을 높여서 중계 신호의 생성 및 송신을 위하여 많은 무선 자원을 소모하는 것은 비효율적일 수 있다. 따라서, 중계 레벨(

)을 낮추는 대신 제1 무선 채널에 대한 채널 상태 정보의 용량(

)을 높여서, 더욱 정확한 빔 포밍을 수행하는 것이 보다 효율적일 수 있다. For example, assume that the channel state of the first radio channel is very good, and the destination node is very far from the relay node, so that the channel state of the second radio channel is poor. In this case, the relay level (

It may be inefficient to consume a large amount of radio resources for generating and transmitting a relay signal by increasing a). Therefore, the relay level (

Capacity of the channel state information for the first wireless channel instead of

), It may be more efficient to perform more accurate beamforming.

)을 낮추고, 중계 신호의 파워를 높이 는 것이 보다 효율적일 수 있다. On the contrary, if the channel state of the first radio channel is poor and the destination node is very close to the relay node so that the channel state of the second radio channel is very good, the capacity of the channel state information for the first radio channel (

Lowering the power and increasing the power of the relay signal can be more efficient.

) 또는 상기 중계 레벨(

) 중 적어도 하나를 제어할 수 있다. At this time, the radio resource allocator 220 stores the capacity of the channel state information such that the signal to interference and noise ratio (SINR) of the received signal received by the target node is maximized.

) Or the relay level (

Control at least one of

) 및 중계 레벨(

)이 어떤 값을 갖는 경우에 목적 노드가 수신하는 수신 신호의 신호 대 간섭 및 잡음 비(Signal to Interference and Noise Ratio)가 최대가 되는지를 판단하여 채널 상태 정보의 용량(

) 및 중계 레벨(

)을 제어할 수 있다. That is, the radio resource allocator 220 may determine the capacity of the channel state information in consideration of the available radio resources.

) And relay level (

) Has a value, and determines the maximum signal to interference and noise ratio of the received signal received by the destination node to determine the capacity of the channel state information (

) And relay level (

) Can be controlled.

) 또는 중계 레벨(

)과 관련된 제어 정보를 이웃 노드들로 전달한다.In addition, the control information transfer unit 230 is the capacity of the controlled channel state information (

) Or relay level (

Control information related to the) is transmitted to the neighbor nodes.

For example, it is assumed that a radio resource allocation system for space division multiple access communication according to the present invention is installed at a source node.

)에 따라 채널 상태 정보를 소스 노드로 피드백하도록 제어 정보 전달부(230)는 제어된 채널 상태 정보의 용량(

)과 관련된 제어 정보를 목적 노드로 전달할 수 있다. 이 때, 중계 노드가 제어된 중계 레벨(

)에 따라 중계 신호를 생성하도록 제어 정보 전달부(230) 는 제어된 중계 레벨(

)을 중계 노드로 전달할 수 있다.In this case, the capacity of the channel state information controlled by the target node (

Control information transfer unit 230 to feed back the channel state information to the source node according to the

) Can be passed to the destination node. At this point, the relay node controls the controlled relay level (

In order to generate a relay signal according to the control information transmission unit 230 is controlled relay level (

) Can be passed to the relay node.

In addition, the destination node may feed back channel state information to the source node according to the capacity of the controlled channel state information. In this case, the source node may generate a source signal by beamforming the data stream using the channel state information fed back from the target node. The relay node generates a relay signal relaying the source signal according to the controlled relay level.

In this case, the destination node may grasp the beamforming vector based on the channel state information, and detect the source signal using the channel state information. In addition, the destination node may receive a relay signal from the relay node. Thus, the destination node can detect the source signal and the relay signal in a cooperative relationship with each other.

As a result, the present invention can achieve higher channel capacity, data rate, SINR, etc. by detecting both the source signal and the relay signal generated by appropriately allocating radio resources.

3 is a flowchart illustrating a signal transmission process between nodes when a capacity or relay level of channel state information is controlled at a target node according to an embodiment of the present invention.

Referring to FIG. 3, the target node may estimate a channel state of a wireless channel formed between the target node and the relay node for a long term. That is, the relay node transmits a pilot signal to the target node, and the target node estimates the channel state of the radio channel formed between the target node and the relay node using the pilot signal.

The source node also broadcasts the pilot signal to the destination node and the relay node. At this time, the destination node and the relay node estimates the channel state of the radio channel formed with the source node using the pilot signal.

) 또는 중계 레벨(

) 중 적어도 하나를 제어한다. At this time, the target node may consider the channel state of the radio channel formed with the source node and the channel state of the radio channel formed with the relay node.

) Or relay level (

Control at least one of

)이 미리 고정(fixed)된 경우, 목적 노드는 채널 상태 정보의 용량(

)을 고려하여 중계 레벨(

)을 제어할 수 있다. 반대로, 중계 레벨(

)이 미리 고정된 경우, 목적 노드는 중계 레벨(

)을 고려하여 채널 상태 정보의 용량(

)을 제어할 수 있다. 또한, 목적 노드는 동시에 채널 상태 정보의 용량(

) 및 중계 레벨(

)을 제어할 수도 있다.At this time, the capacity of the channel state information (

If the node is fixed in advance, the destination node may determine the capacity of the channel state information.

), Considering the relay level (

) Can be controlled. Conversely, the relay level (

) Is fixed in advance, the destination node

Taking into account the volume of channel state information (

) Can be controlled. In addition, the destination node can simultaneously determine the capacity of the channel state information (

) And relay level (

) Can also be controlled.

)이 높게 제어될 수 있다. 반대로, 채널 상태가 신호 중계에 무선 자원을 더 사용하는 것이 효율적인 것으로 판단되면, 중계 신호의 중계 레벨(

)이 높게 제어될 수 있다.For example, if the destination node determines that it is more efficient to use radio resources for beamforming, the capacity of the channel state information may be improved so that beamforming performance can be improved.

) Can be controlled high. Conversely, if the channel condition determines that it is efficient to use more radio resources for signal relaying, the relay level of the relay signal (

) Can be controlled high.

) 또는 중계 레벨(

)과 관련된 제어 정보를 소스 노드 및 중계 노드로 전달한다. 이 때, 목적 노드는 다양한 시기에 여러 가지 방식으로 제어 정보를 전달할 수 있다. The destination node is the capacity of the channel state information.

) Or relay level (

The control information related to the) is transmitted to the source node and the relay node. In this case, the destination node may transmit control information in various ways at various times.

)에 따라 목적 노드와 소스 노드 사이에 형성된 무선 채널의 채널 상태 정보(CSI)를 소스 노드로 피드백한다. 예를 들어, 채널 상태 정보의 용량(

)이 높게 제어되었다면, 목적 노드는 높은 양자화 레벨(quantization level)을 갖는 채널 상태 정보(CSI)를 피드백할 수 있다.In addition, the destination node may determine the capacity of the controlled channel state information (

The channel state information (CSI) of the radio channel formed between the target node and the source node is fed back to the source node. For example, the capacity of channel state information (

If is controlled high, the destination node can feed back channel state information (CSI) with a high quantization level.

)에 따라 채널 상태 정보(CSI)를 소스 노드로 피드백할 수 있다. 다만, 중계 노드는

와는 다른 용량을 갖는 채널 상태 정보(CSI)를 소스 노드로 피드백할 수도 있다. In addition, the relay node may also feed back channel state information (CSI) of the radio channel formed between the source node and the relay node to the source node. At this time, the relay node also controls the capacity of the controlled channel state information (

), Channel state information (CSI) may be fed back to the source node. However, the relay node

Channel state information (CSI) having a different capacity may be fed back to the source node.

)에 따라 빔 포밍 벡터를 생성 또는 선택하고, 그 빔 포밍 벡터를 기초로 데이터 스트림을 빔 포밍하여 소스 신호를 생성한다. 생성된 소스 신호는 소스 노드에 설치된 다수의 안테나들을 통하여 공간 분할 접속 방식에 따라 목적 노드 및 중계 노드로 전송된다. The source node is the capacity of the channel state information (

Generate or select a beamforming vector, and generate a source signal by beamforming a data stream based on the beamforming vector. The generated source signal is transmitted to the destination node and the relay node according to the spatial division access scheme through a plurality of antennas installed in the source node.

)이 높게 제어되었다면, 소스 노드는 실제 무선 채널에 부합하는 빔 포밍을 수행할 수 있다. 이 경우, 전체적인 빔 포밍이 성능이 향상될 수 있다. If the capacity of the channel state information (

If is controlled to be high, the source node may perform beamforming to match the actual wireless channel. In this case, the overall beamforming performance can be improved.

)에 따라 중계 신호를 생성한다. 예를 들어, 중계 노드는 중계 레벨(

)에 따라 중계 신호의 파워, 중계 신호의 중계 시간 및 주파수 대역 등을 결정할 수 있다. The relay node receives the source signal via a wireless channel and generates a relay signal. At this point, the relay node is in the controlled relay level (

To generate a relay signal. For example, a relay node might be a relay level (

), The power of the relay signal, the relay time and the frequency band of the relay signal can be determined.

The destination node detects the source signal and the relay signal transmitted from the source node. At this time, the target node may sequentially detect the source signal and the relay signal, and may simultaneously detect the source signal and the relay signal.

)이 크게 제어된 경우, 소스 신호의 파워가 클 수 있고, 중계 레벨(

)이 높게 제어된 경우, 중계 신호의 파워가 클 수 있다. 결국, 본 발명은 주어진 무선 환경에 따라 적응적으로 빔 포밍에 할당되는 무선 자원 및 중계 신호 생성에 할당되는 무선 자원을 적절히 할당할 수 있다. 따라서, 목적 노드는 보다 높은 SINR 또는 데이터 전송률을 달성할 수 있다. At this time, the capacity of the channel state information (

) Is largely controlled, the power of the source signal may be large, the relay level (

) Is controlled high, the power of the relay signal may be large. As a result, the present invention can appropriately allocate radio resources allocated to beamforming and relay signals generated adaptively according to a given radio environment. Thus, the destination node can achieve higher SINR or data rate.

4 is a flowchart illustrating a signal transmission process between nodes when a capacity of channel state information is fixed and a relay node determines a relay level according to an embodiment of the present invention.

=X)은 고정되어 있으며, 중계 노드는 파일럿 신호를 통하여 목적 노드와 형성된 무선 채널의 채널 상태를 인지한다. Referring to FIG. 4, the capacity of channel state information (

= X) is fixed, and the relay node recognizes the channel state of the radio channel formed with the destination node through the pilot signal.

The source node also broadcasts the pilot signal to the destination node and the relay node. At this time, the destination node and the relay node estimates the channel state of the radio channel formed with the source node using the pilot signal.

)을 제어한다. 이 때, 중계 노드는 고정된 채널 상태 정보의 용량(

=X)을 더 고려하여 중계 레벨(

)을 제어할 수 있다. 즉, 중계 노드는 채널 상태 정보의 용량(

=X)이 고정된 환경에서, 주어진 무선 환경에 어떠한 중계 레벨이 적합한 지를 판단하고, 중계 레벨(

)을 제어한다.The relay node considers the channel state of the radio channel formed with the destination node or the channel state of the radio channel formed with the source node.

). At this time, the relay node may have a fixed capacity of channel state information.

= X), further considering the relay level (

) Can be controlled. In other words, the relay node is the capacity of the channel state information (

In an environment where X is fixed, it is determined which relay level is suitable for a given wireless environment, and the relay level (

).

=X)에 따라 소스 노드와 형성된 무선 채널의 채널 상태 정보(CSI)를 소스 노드로 피드백한다. In addition, the destination node and the relay node may have a fixed capacity of fixed channel state information.

= X), the channel state information (CSI) of the wireless channel formed with the source node is fed back to the source node.

=X)에 따라 피드백된 채널 상태 정보를 기초로 빔 포밍 벡터를 선택한다. 이 때, 소스 노드는 선택된 빔 포밍 벡터를 이용하여 데이터 스트림을 빔 포밍하여 소스 신호를 생성한다.The source node is the capacity of fixed channel state information (

= Beamforming vector is selected based on the channel state information fed back according to X). At this time, the source node beamforms the data stream using the selected beamforming vector to generate a source signal.

The relay node generates a relay signal by relaying the source signal according to the controlled relay level. If the relay level is controlled to be high, the power of the relay signal, the relay time, etc. may increase.

The destination node also detects source signals and relay signals transmitted from the source nodes. At this time, the target node may simultaneously detect the source signal and the relay signal, or may sequentially detect the source signal.

5 is a flowchart illustrating a radio resource allocation method for space division multiple access communication according to an embodiment of the present invention.

Referring to FIG. 5, a radio resource allocation method for spatial division multiple access communication according to an embodiment of the present invention recognizes channel states of radio channels formed between neighboring nodes including a source node, a relay node, and a destination node. (S510).

In addition, the radio resource allocation method for spatial division multiple access communication according to an embodiment of the present invention is the capacity of the channel state information fed back from the destination node to the source node or the source transmitted from the source node according to the channel state At least one of the relay levels of the relayed signal signal is controlled (S520).

At this time, controlling the at least one of the capacity or relay level of the channel state information (S520) in accordance with the channel state in consideration of the ratio of the relay level to the capacity of the channel state information or the capacity of the channel state information or Controlling at least one of the relay levels.

At this time, controlling the at least one of the capacity or relay level of the channel state information (S520) is a channel state of the first wireless channel formed between the source node and the target node and between the relay node and the target node. And comparing at least one channel state of the formed second wireless channel to control at least one of the capacity of the channel state information and the relay level.

At this time, controlling the at least one of the capacity or relay level of the channel state information (S520) is such that the signal to interference and noise ratio of the received signal received by the target node to the maximum And controlling at least one of the capacity of the channel state information or the relay level.

In this case, in the controlling of at least one of the capacity or the relay level of the channel state information (S520), the higher the capacity of the channel state information, the lower the relay level, and the higher the relay level, the higher the level of the channel state information. The method may include controlling at least one of the capacity of the channel state information or the relay level to decrease the capacity.

In this case, the controlling of at least one of the capacity of the channel state information or the relay level (S520) may be performed by considering the capacity of the fixed channel state information when the capacity of the channel state information is fixed. And controlling the capacity of the channel state information in consideration of the fixed relay level when the relay level is fixed.

In addition, although not shown in FIG. 5, the method for allocating a radio resource for spatial division multiple access communication according to an embodiment of the present invention includes controlling the capacity of the channel state information or control information related to the relay level to the neighboring node. It may further comprise the step of delivering to the.

Matters not described with reference to FIG. 5 have been described in detail with reference to FIGS. 1 to 4, and thus will be omitted below.

The radio resource allocation method for space division multiple access communication according to the present invention may be implemented in the form of program instructions that can be executed by 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 those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

As described above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

1 is a diagram illustrating a space division multiple access communication network according to an embodiment of the present invention.

2 is a block diagram illustrating a radio resource allocation system for spatial division multiple access communication according to an embodiment of the present invention.

3 is a flowchart illustrating a signal transmission process between nodes when a capacity or relay level of channel state information is controlled at a target node according to an embodiment of the present invention.

4 is a flowchart illustrating a signal transmission process between nodes when a capacity of channel state information is fixed and a relay node determines a relay level according to an embodiment of the present invention.

5 is a flowchart illustrating a radio resource allocation method for space division multiple access communication according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

210: channel state recognizer

220: radio resource allocation unit

230: control information transmission unit

Claims (20)

A channel state recognizing unit for recognizing a channel state of wireless channels formed between neighboring nodes including a source node, a relay node, and a destination node; And A radio resource allocator configured to control at least one of a capacity of channel state information fed back from the destination node to the source node or a relay level of a relay signal to which a source signal transmitted from the source node is relayed according to the channel state Radio resource allocation system for spatial division multiple access communication comprising a. The method according to claim 1, The radio resource allocation unit And controlling at least one of the capacity of the channel state information or the relay level in consideration of the ratio of the relay level to the capacity of the channel state information according to the channel state. Allocation system. The method according to claim 1, The radio resource allocation unit Comparing the channel state of the first radio channel formed between the source node and the destination node and the channel state of the second radio channel formed between the relay node and the destination node to determine the capacity of the channel state information or the relay level. A radio resource allocation system for spatial division multiple access communication, characterized in that it controls at least one. The method according to claim 1, The radio resource allocation unit And controlling at least one of the capacity of the channel state information or the relay level such that a signal to interference and noise ratio of a received signal received by the destination node is maximized. Radio resource allocation system for access communication. The method according to claim 1, The radio resource allocation unit The relay level is reduced when the capacity of the channel state information is higher, and at least one of the capacity of the channel state information or the relay level is controlled so that the capacity of the channel state information is decreased as the relay level is higher. A radio resource allocation system for space division multiple access communication. The method according to claim 1, The radio resource allocation unit When the capacity of the channel state information is fixed, the relay level is controlled in consideration of the fixed capacity of the channel state information. When the relay level is fixed, the channel state information is considered in consideration of the fixed relay level. A radio resource allocation system for space division multiple access communication, characterized in that for controlling the capacity of. The method according to claim 1, And the relay level is associated with at least one of a relay time of the relay signal, power of the relay signal, or a frequency band of the relay signal. The method according to claim 1, Control information transfer unit for transmitting the control information related to the capacity or the relay level of the controlled channel state information to the neighboring nodes Radio resource allocation system for spatial division multiple access communication further comprising. The method according to claim 1, The source node generates the source signal by beamforming a data stream using the channel state information fed back from the destination node according to the capacity of the channel state information. Radio resource allocation system for communication. The method according to claim 1, And the relay node generates the relay signal in which the source signal is relayed according to the controlled relay level. The method according to claim 1, And the destination node feeds back the channel state information to the source node according to the controlled capacity of the channel state information. 10. The method of claim 9, And the destination node detects the source signal generated by beamforming the data stream and the relay signal relayed according to the relay level. Recognizing the channel state of the free channels formed between neighboring nodes including a source node, a relay node and a destination node; And Controlling at least one of a capacity of channel state information fed back from the destination node to the source node or a relay level of a relay signal in which a source signal transmitted from the source node is relayed according to the channel state; Radio resource allocation method for spatial division multiple access communication comprising a. 14. The method of claim 13, Controlling at least one of the capacity of the channel state information or the relay level Controlling at least one of the capacity of the channel state information or the relay level in consideration of the ratio of the relay level to the capacity of the channel state information according to the channel state. Radio resource allocation method. 14. The method of claim 13, Controlling at least one of the capacity of the channel state information or the relay level Comparing the channel state of the first radio channel formed between the source node and the destination node and the channel state of the second radio channel formed between the relay node and the destination node to compare at least one of the capacity of the channel state information or the relay level. And a step of controlling one radio resource allocation method for spatial division multiple access communication. 14. The method of claim 13, Controlling at least one of the capacity of the channel state information or the relay level Controlling at least one of the capacity of the channel state information or the relay level such that a signal to interference and noise ratio of a received signal received by the destination node is maximized. Radio resource allocation method for split multiple access communication. 14. The method of claim 13, Controlling at least one of the capacity of the channel state information or the relay level Controlling at least one of the capacity of the channel state information or the relay level such that the relay level decreases as the capacity of the channel state information increases, and the capacity of the channel state information decreases as the relay level increases. A radio resource allocation system method for space division multiple access communication, characterized by the above-mentioned. 14. The method of claim 13, Controlling at least one of the capacity of the channel state information or the relay level When the capacity of the channel state information is fixed, the relay level is controlled in consideration of the fixed capacity of the channel state information. When the relay level is fixed, the channel state information is considered in consideration of the fixed relay level. And controlling the capacity of the radio resource allocation method for spatial division multiple access communication. 14. The method of claim 13, Transferring control information related to the capacity of the controlled channel state information or the relay level to the neighbor nodes; The radio resource allocation method for space division multiple access communication further comprising. A computer-readable recording medium in which a program for executing the method of any one of claims 13 to 19 is recorded.

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