Performance Analysis Of Relay System Based On Alamouti Scheme

Recently, with the demands for multimedia communications and broadband data services of wireless communication users increasing, how to provide high speed and high quality communication in mobile environment becomes one of the research focuses. In this paper, MIMO and relay, which are two research hotspots of mobile communication, are combined to analysis the performance of wireless communication system.Multiple input and multiple output(MIMO), which uses multiple antennas at both the transmitter and receiver, thus forms plenty of spatial channels, can increase the capacity of the system and the transmission quality. Relay which is a node between the transmitter and receiver,and that receive the signal from the transmitter and then transmit it to the receiver, can improve the coverage area without an additional transmit power.This paper focused on the diversity technology based on MIMO and the forward mode of relay. On the basis above, we build the system with the Alamouti scheme and one relay, Assuming the channel model, deriveing and simulating the algorithm of the system performance. The main contents are as follows:Firstly, research the MIMO communication system. MIMO is mainly based on space diversity, we discuss the performance of receiver and transmitter from the receive and transmit diversity respectively. We highlight two kinds of the Alamouti transmit scheme, describing the process of send and receive.Secondly, research the relay system. Relay system can be divided into multiple models from a single antenna and multi-antennas division, or from a single relay and multi-relays division, or from the single user and multi-users criterion. The main operation mode of relay are receiving and forwarding. Before analyzing the system, we should assume the working mode of the transmitter,the relay and the receiver first.Thirdly, research the MIMO system based on relay. Combining the MIMO and relay technology, establishing a system with one user and one relay. In order to facilitate research, we derived the algorithm of the system performance with the Alamoutischeme. Finally, simulating the performance of the model which we build with Monte Carlo method, and compare the result with the theoretical analysis result.Proving the correctness of the theoretical expressions ultimately.