Research On Relay Selection And Power Allocation In Cooperative Communication Network

With the rapid development of wireless communication technology, the requirements of wireless communication system performance for data processing become higher and higher. Cooperative communication technology can effectively reduce the influence of channel fading characteristics brought to communication performance, and improve the performance and reliability of network. The basic idea is that in a communication environment which contains many multiple single-antenna terminals, the terminals share their antennas in a agreed manner mutually to form a virtual multi-antenna system, then enhance the diversity effect of the system, and improve the transmission performance of the system.Firstly, this paper researched the problem of relay selection in cooperative communication network, and introduced several kinds of relay selection algorithms,then we analyzed the advantages and disadvantages of different algorithms, also we proposed an improved SNR-threshold-based relay selection algorithm, and the simulation result verified the algorithm improved the performance of system.Secondly, this paper analyzed the power allocation problem of cooperation communication network, elaborated two common power allocation algorithm, and analyzed the symbol error rate performance and interrupt capability of the two power allocation scheme. Simulation result verified both the two programs improved the performance of cooperative communication network.Finally, we combined the advantages of both relay selection and power distribution technologies, researched joint relay selection and power allocation optimization problem. We proposed two joint optimization schemes based on relay selection and power allocation under different network scenarios, resolved the problem of network energy efficiency under different environmental conditions, contrary to the different network conditions, the joint optimization program is divided into two cases. One case is that to meet the given network performance qualification, minimize the network power optimization programs, the other case is that when given network power consumption constraints, optimizied the energy efficiency of cooperative communication network.then we analysed the joint optimization problem, and we obtained the closed expressions optimal solution for different schemes.Simulation result certificated the optimization program improved the performance of cooperative communication network.