Research On Access Control And Load Balancing Algorithm For Heterogeneous Wireless Networks

With the rapid development of communication technology,different networks have significant advantages in bandwidth,delay and so on.In order to meet the growing needs of diverse businesses,the future mobile communication system must be a heterogeneous wireless network that is combined with a variety of networks and has a complementary advantage.Resource management of heterogeneous wireless networks is an important mechanism for controlling business communication and using the resource of radios efficiently.It covers a variety of technologies.Among them,the function of the service access control is to control business access to various wireless networks and improve the utilization of network resources.The technology of load balancing can solve the problems of unreasonable distribution of resources,low system capacity and large service difference caused by the uneven distribution of business,which is of great importance for radio resource management.The existing access control and load balancing algorithms can improve the utilization of network resources and ensure the balance of the load level of each network to a certain extent.However,the benefits of both the network and the users are not taken into account,and the user preferences are ignored.And the accuracy of the solution needs to be improved.In order to solve the above problems,the business access control and load balancing algorithm are studied in depth.The multi-objective evolutionary algorithm based on decomposition can be used in the access control problem with the advantages of cooperative optimization of multiple targets and high accuracy.On this basis,combined with the service transfer strategy,a joint load balancing algorithm considering user preferences is proposed.The specific contents of the paper include the following two aspects.Firstly,Aiming at most of the existing access control algorithms based on optimization algorithm only consider two optimization objectives and transform them into single objective problem,which restricts the relative relationship between the optimization objectives and the accuracy of the solution needs to be improved,an access control algorithm based on multiobjective optimization is proposed.The optimization goals of the algrithom are expanded to three,which is to minimize the blocking rate,minimize the total occupied resources and load balancing.Then the MOEA/D is used for preliminary optimization.And the Pareto optimal solution set,that is,the optimal access scheme,is obtained by using non dominated sorting.Finally,simulation experiments show that the proposed algorithm can improve the utilization rate of network resources,significantly reduce the traffic blocking rate,and provide various optimal access schemes for decision makers.Secondly,aiming at the fact that the existing load balancing algorithms can not effectively integrate business transfer and access control and lack of consideration for user preferences,a joint load balancing algorithm based on user preferences is proposed.First of all,according to a certain business transfer strategy,part of the business are transferred from overload network to the light load network.Then the objective function is designed to maximize the satisfaction of preference,which constitutes a multi-objective access model with the minimization of the total resource utilization and the minimization of the load variance.Finally,the Pareto optimal solution set is obtained by using non dominated sorting.The simulation experiment is carried out to verify that the algorithm can effectively balance the load of each network,and improve the user satisfaction and resource utilization.