Research About Resource Allocation Algorithm Based On Cognitive OFDM

The development of mobile communication,it can reflect the current radio technology of explosive development,it is of high quality,high service,high quality and so on various business needs,resulting in the spectrum resources cannot meet the demand caused by the shortage of.Cognitive radio(Cognitive Radio CR)is a wireless communication system with intelligence and flexibility,can perceive the external environment and the detection of no idle time and spectrum occupied around in complex system environment under the condition of changing the system parameters adaptively change the use of artificial intelligence technology,can realize the dynamic spectrum sharing and the best performance of communication.Orthogonal frequency division multiplexing(Orthogonal,Frequency,Division,Multiplex,OFDM)can dynamically allocate spectrum resources,flexibly select subcarrier transmission and power allocation,so as to dynamically allocate spectrum resources.Cognitive OFDM combines the advantages of both,can meet the needs of spectrum allocation,so the allocation of radio spectrum resources based on cognitive OFDM is the current research hotspot.This paper studied the cognitive radio resource allocation algorithm based on OFDM,introduces the background and current situation of cognitive radio and OFDM and related technology,and cognitive OFDM system on resource allocation system model and the classical algorithm.In order to solve the problem of resource shortage caused by the failure of users to make full use of spectrum resources in cognitive OFDM system,this paper proposes an optimal resource allocation strategy based on fish swarm algorithm.According to the principle of proportion fairness subcarrier allocation,rational allocation of power through the artificial fish swarm algorithm for cognitive users,taking into account the cognitive users and licensed users do not interfere with each other,taking into account the fitness function as the judge the power distribution,and realize the maximization of the cognitive OFDM system capacity.The experimental results show that the algorithm in the cognitive user requirements of the authorized user interference is less than the threshold value,ensure the fairness of the cognitive user subcarrier and power allocation,effectively improve the spectrum utilization rate,to achieve the maximum transmission rate of the system.In this paper,a spectrum resource allocation strategy based on cuckoo search algorithm is proposed.Guarantee the principle of fairness,reasonable allocation of power through the cuckoo search algorithm of cognitive users,meet the authorized user without interference,at the same time as the fitness function to determine the rationality of power allocation,to maximize the cognitive capacity of the OFDM system.The experimental results show that the proposed algorithm can guarantee fairness,improve the efficiency of spectrum utilization,and achieve the maximum transmission rate.At the same time,under the same experimental environment,the algorithm is simulated by the fish swarm algorithm and the cuckoo algorithm.The experimental results show that the cuckoo search algorithm is better than the fish swarm algorithm,and the system capacity is maximized.