Research On Relay Selection Algorithm Of Relay Channel Under The Condition Of Error

Due to the repaid development of today's world,prompting a series of important changes to the wireless communication.Wireless communication is widely used in broadcast,mobile communication technology,underwater communications,military and other aspects,which urging us demanding and relying on it more and more strongly.Under this trend,we must increase the consumption of radio wireless spectrum resources,which causing a series of conflicts that make for the research on wireless communication technology caused a certain degree of obstruction,and it promotes us to seek a new generation of wireless communications technology.At present,how to improve the utilization of spectrum resources more fully and more effectively has become a core issue in the field of wireless communication technology.With the introduction of beamforming technology,which providing broader prospects for communication technology.Now it has been adapted to the single-user,multi-user,single-antenna and multi-antenna scenario,in which multiple-input multiple-output( MIMO) system is more typical.The use of beamforming technology can gain benefits in a desired position,while get nulling in the interference directions,so as to improve the quality of service(Qo S) effectively.On the other hand,because of the amount of information carried by the source of information is too large,the distance and the influence of noise and other factors,the destination users can't obtain the expected spectrum resources.The introduction of cooperative relay technology can improve it effectively.However,a considerable part of the current research on the relay channel is based on the condition that the channel state information(CSI) is under ideal condition,and most did not consider the effects of transmission power.But predictable,due to the influence of noise and external factors,the channel state information will be changed.If the channel state information is not properly analyzed and processed,it will have a certain impact on the quality of the communication link in the scene.Aiming at the above problems,this paper puts forward the relay selection algorithm under the condition of relay channel error,its essence is to further improve the utilization of spectrum resources.The main work is as follows:According to the actual environment,this paper designs a practical and efficient beam forming device,which takes into account the difference of each relay environment.The communication link fadingcharacteristics between the relays and the users are different.For example,some links are under deep fading,whereas others are in good conditions.Consequently,not all the relay nodes are suitable for participating relay nodes beamforming.At the same time,the coexistence of primary users and secondary users makes the design of the relay selection algorithm become difficult.The key of this paper lies in resolving the problem of the spectrum resources shortage and providing reliable communication services,discussing a compromised resource allocation policy under the bounded model of channel error between minimum transmission power and the optimal relay subset.Aiming at the scenario where coexistence of primary users and secondary users,analysing from two aspects about the fully of collaborative relay and part of the collaborative relay.Then turning the nonconvex problem into a convex problem by the sparse lifting scheme,and using an iterative algorithm to solve the power.Finally, the simulation results verify the feasibility of the proposed algorithm.