Research On Transmission Performance Of Wireless Relay Communication Network

In the recent years, with the development of wireless communication technology developing rapidly, the multimedia communication with the need for more bandwidth and higher transmission rate, gradually became the focus of modern wireless communication services. Thus, as to improve the transmission rate and reliability of communication system, MIMO technology and cooperative communication technology, has been widely concerned.MIMO technology is one of communication technology to improve the communication performance of the system equipped with multiple antennas conditions in the device, and cooperative communication technology is a transmission technology to realize the transmission technology of virtual MIMO, in the equipment equipped with only one antenna, sharing other mobile users antenna. The technology can provide multiplexing and diversity gain corresponding to the communication system, to improve the communication system performance.This paper studies the distributed cooperative communication system:the source node and the relay nodes cooperate to send signals to the destination node. In the process of the source node and relay node communication, the protocol is the decode-and-forward protocol. That is to say, the relay node decodes the signal received from the source node, then re-encoded, finally sent to the destination node, we establish a system model, give the general hypothesis and multiplexing gain, focus on the transmission performance of cooperative scheme of the relay communication system.On the basis of the literature [1], we analyze the system model in the article, the related performance of channel model and system (setting power limiting conditions), and we have the data simulation by MATLAB and the corresponding verification. According to the characteristics of the actual communication environment, based on the study of literature, we puts forward the new channel model, make the communication environment be more in line with the actual situation。In the fourth chapter, first proposed the angle formed between the source node and relay node transmission line link with the source node and the destination node transmission line link (the article referred to as trunk angle).Then, we establish a new channel model, the channel between the source node and the relay node link fading obeying Rician distribution, We studied the effect of trunk angle on the transmission performance of the system, in the channel model changes before and after modification. Finally, through data simulation, We analysis and verification the system transmission performance improved.