Resource Allocation Algorithm In Cognitive Heterogeneous Network Using Convex Optimization

There is great difference and complementarity for different radio access technologies in capacity, coverage and transmission rate. Thus the heterogeneous wireless networks which allow multiple networks coexist could meet different users’ needs. Cognitive networks are also gradually becoming heterogeneous, which could improve the utilization of network resources and meet the needs of different users. Rational resource allocation scheme can reduce the energy consumption and improve the utilization efficiency of network resources. Thus in this paper, resource allocation algorithm in the cognitive heterogeneous networks is researched to improve system resource utilization and reduce transmission delay.First of all, the development situation of cognitive heterogeneous networks is reviewed, and we focus on the research of existing resource allocation algorithm in heterogeneous network. Then we decide that the convex optimization method is used for the resource allocation in cognitive heterogeneous network.Secondly, the basic concepts and properties of convex optimization are studied. Due to the special nature of cognitive heterogeneous network, the basic arrival model of primary user is discussed, including the model based on Poisson process, birth and death process and primary user activity index.Once again, a cognitive resource allocation algorithm heterogeneous network based on convex optimization methods is proposed. The optimization goal is to minimize the system delay in the limitation of the system resource. The primary users’ arrival is considered in the objective function. And the algorithm is applied in the different models of primary user’s arrival. By Matlab simulation, the results show that the proposed algorithm has better delay performance than the algorithm without considering the arrival of primary users.Finally, considering that secondary user could not perfectly sense the condition of primary users, in order to avoid causing interference to the primary user, the primary user interference tolerance limit is introduced in the algorithm, and the limitation of the interference caused by the secondary users is added in the constrains. The algorithm could be applied in the different primary user arrival model according to the simulation results.