Relay Selection and Power Control Based on Multi - relay and Multi-antenna Cognitive Wireless Network

Abstract

Cognitive radio has been widely used as an effective way to solve the problems of shortage of available spectrum resources and low spectrum utilization. In this paper, spectrum sensing, spectrum dynamic access and power allocation in cognitive wireless networks are analyzed. In addition, in order to improve the spectrum sensing performance and data transmission rate of cognitive wireless networks, relay cooperation technology, multi-antenna technology, single relay selection technology and full-duplex technology are applied to different cognitive wireless networks. Firstly, the cognitive model of multi-relay and multi-antenna is described, and then the optimal single relay selection is made in the information transmission stage.Secondly, the relay selection and power optimization of multi-relay multi-antenna full duplex system based on hybrid spectrum sensing are studied. The optimal single relay is selected by using the optimal relay selection scheme. Then, the optimal multi-antenna power allocation strategy for single relay node is proposed in the case of hybrid spectrum access mode. We have set the self-interference to a constant value, and then compare the full duplex mode with the half duplex mode in numerical simulation. The FD system using the combination of the Optimal relay selection algorithm and the Power control algorithm proposed in this paper increases the transmission rate by about 50% compared with the full-duplex basic system. System performance has been Opitimized.