Research On Spectrum Allocation Method Based On Cognitive Technology

Due to the rapid progress of signal processing and other technologies and the rapid growth of user needs,the field of wireless communications has developed rapidly.Under the existing static spectrum allocation method,new users cannot be allocated to the available frequency band for a period of time,resulting in spectrum shortage.In response to this problem,the wireless cognitive network uses dynamic spectrum allocation and access sharing to improve the network performance and resource utilization,and alleviates the problem of resource constraints.The essence of the spectrum allocation problem is that the cognitive network uses the spectrum opportunity and the authorized network to share the same frequency band under the premise of ensuring that the authorized network can communicate normally.Resource sharing in spectrum allocation includes both sharing between primary and secondary users in the licensed band,and sharing between secondary users in the cognitive network.Based on the above expressions,this paper studies the spectrum allocation problem of primary users,secondary users,cellular users,and D2 D users in cognitive networks.The three specific points of research are as follows:1? To solve the problem that the traditional power control algorithm limits the transmission power of cognitive users and affects the communication quality,a multi-user spectrum allocation method under the Rubinstein game model is proposed.By using cognitive users as participants and at the cost of bandwidth lost due to delay,a multiplayer game model that benefits from the final bandwidth share is established.First,by establishing a benefit function composed of a price function and a signal-to-interference-to-noise ratio,the selfish behavior of individual users is prevented.The transmission power of cognitive users is reduced through Newton's iterative formula,and the corresponding link quality is obtained according to the interference between each user.The discount factor in economics is mapped to the user's link quality;finally,the cognitive is adjusted according to the link quality.The user sub-game sequence makes the total transmission rate of the network reach a relatively stable state.2?For multiple D2 D multiplexed cellular links,the increase in the number of D2 D pairs has caused shortages of spectrum resources and serious interference to cellular users.A clustering model centered on cellular users is established and aresource allocation algorithm for D2 D users in the cluster is proposed.The algorithm calculates the signal-to-interference and noise ratio of each D2 D pair in the cluster on the premise of ensuring the maximum throughput demand of the cellular user,and reconstructs the interference matrix,available matrix and benefit matrix through the mapping relationship and probability model.And through the new interference topology map to determine the accessible D2 D pairs and access priorities in the cluster,and maximize the number of user access under the interference tolerance.3?Aiming at the problems of low transmission power and low network transmission rate caused by limited battery capacity of low-power D2 D communication equipment,a D2 D relay selection algorithm based on HUS energy collection model is proposed.In this algorithm,D2 D users in the network are divided into multiplexing set and relay set by the improved graph theory model.For D2 D users with poor energy collection in the multiplexing set,relay users are selected in the relay set,and the throughput of the relay link is improved by cooperative communication.