Research Of Resource Allocation Mechanisms In Cognitive Radio System

In recent years,with the rapid development of wireless communication service and the increasing demand for information transmission speed and quality of wireless communication,the available spectrum resources become more and more intense.Therefore,how to make full use of the spectrum resources has been a key issue in wireless communication.As a key technology that can effectively improve the utilization of spectrum,cognitive radio has become a hot in the research on wireless communication.Cognitive radio technology allows secondary users to dynamically access the licensed frequency for data transmission on the premise of guaranteeing the communication quality of the primary user,which can significantly improve the spectrum utilization and system capacity.However,how to apply cognitive radio technology to real scenes in real life and how to further improve the performance of cognitive system are still the key problems to be solved urgently.Therefore,this paper puts forward the corresponding solutions in view of the above problems.The innovative work of this article is as follows.In most of the CR network scenarios,there are multiple primary users(PUs)with intense traffic.A novel multi-PUs multi-state CR access mechanism and the corresponding multi-power access strategy based on the primary user traffic were proposed to address this problem.The mathematical expression of the throughput of the cognitive system under the novel access strategy is derived,and the computer simulation is carried out.The results show that the proposed method can enable the SU to choose the best licensed channel for data transmission and adopt the multi-power access strategy adaptively,which not only reduce the interference to the PU,but also maximize the capacity of the CR system.Considering the advantages of the NOMA technology relative to the traditional orthogonal access mode,a cognitive radio system model based on NOMA is proposed in this paper.And in the SSSA model,considering the average transmission power constraint and average interference power constraint,the optimal power allocation algorithm was proposed to maximize the throughput of the CR system.The research results show that the performance of the proposed NOMA based CR model has been significantly improved compared with the traditional orthogonal access CR model,and it can better reflect the principle of fairness.In view of the advantages of the MGMC system compared with the traditional multicast mode,this paper proposed a MGMC CR system model based on SSSA.Then,on the premise of considering the maximum transmission power constraint and the maximum interference power constraint,an optimal power allocation algorithm was proposed,which can maximize the transmission rate of the MGMC CR system.Finally,the performance advantages of the proposed method are verified by computer simulation analysis.