Research On The Strategy Of Relay Selection And Power Allocation For Two-way Cooperative Relay Network

With the growing number of mobile users,the quality of business requirements improve continually,the problem of wireless spectrum shortage and bad wireless transmission environment is increasingly serious.The emergence of collaborative communication provides the new methods of use of space resources,it through the way of collaboration between multiple communicating entities to share limited resources so as to improve the wireless resource utilization.Compared with one-way relay,two-way relay can realize two-way signal transmission and exchange,has higher spectrum efficiency,in recent years,there are a lot of researches on two-way collaboration relay network.Due to the limited system resources,power allocation strategy can improve network performance.Selecting the appropriate relay nodes can make use of the system resources and reduce the interference between the transmission links.This paper is mainly focused on the further research of relay selection and power allocation strategy of two-way collaboration relay network.The major research work of this paper includes:Because of the two-way collaboration relay network's channel capacity,outage probability,SNR(Signal To Noise Ratio)and SER(Symbol Error Ratio)system performance is not ideal.In order to improve the performance of the system,on the one hand,this paper research on relay selection strategy,a multi relay selection algorithm based on minimized outage probability is proposed,the algorithm compares the outage probability of candidate relay with the system set the outage probability threshold,so as to minimize the outage probability,to get the optimal number of relay,.and the simulation results show that the improved strategy obviously improves the system performance.On the other hand,this paper research on power allocation strategy,compared with the traditional single performance,the power allocation strategy of minimized SER and maximized the system capacity,this paper presents combined power allocation strategy,which comprehensively considering the SER and system capacity,through the simulation analysis,it is concluded that this strategy can have a better system capacity,outage probability and SER system performance.In order to further improve the system performance of two-way cooperative relaying network,through the use of fusion coding and routing network coding can further save energy,improve the network throughput.But in the actual multipath fading channel,relay nodes forward unavoidably has a transmission error,which leads to the decrease of the capacity gain of network coding.Channel coding has certain error correction ability through redundancy,to improve the quality of link transmission,Turbo code as a better coding method,in this paper,combining the collaborative communication,network coding and Turbo code together to research,this paper presents joint Turbo-network coding two-way relay collaboration network.Simulation results show that compared with traditional network coding way,the joint Turbonetwork coding strategy improve the transmission capacity,and the transmission performance of the system is improved.