Research On Power Allocatin Algorithm In Cooperative Communication Systems

The cooperative communication technology has high spectral efficiency and good anti-multipath fading performance. It is a suitable technology for high speed data transmission under wireless environment, and has aroused the widespread concern of academics. However, because the structure of cooperative communication network is more complex, the communication between network nodes is subjected to power constraints, and there is multi-hop relay, etc. In order to reduce interference between networks, enhance the stability of the system, and improve the transmission capacity of the system, it is particularly important to use of power resources reasonably and effectively. Therefore, the study of power allocation in cooperative communication has important theoretical significance and application value.We study the basic primciples of the cooperative communication system in depth in the paper. Firstly, we introduce the basic model and key technologies of the cooperative communication system, and describe the relay forwarding protocols, relay selection stagey and typical power allocation algorithm of the cooperative communication system in details. On the basis, we analyze the optimal power allocation problem in amplification forwarding protocol single relay cooperative system, and transform it into the global optimization problems. By using the global optimization ability of artificial fish swarm algorithm, and combining with the advantage of rapid convergence of the particle swarm algorithm, we propose the artificial fish swarm particle swarm algorithm, apply it to minimize the error rate of the objective function for solving the optimal power allocation problem. The way not only ensure that the algorithm has strong ability of global optimum, but also improve the convergence speed and precision.The traditional power allocation algorithms for the multi-relay system use exhaustive search algorithm to choose the optimal set of cooperation relay under the condition of the same power, but they did not take full advantage of power resources and the computational complexity is high. Aiming at the problem, the paper introduces the power allocation factor. We can select the optimal set of cooperative relay adaptively by using the channel statistical information, so as to realize the reasonable power allocation between the source node and the relay, reduce the complexity of the algorithm significantly, make rational use of the system resource, and improve the performance of system.