Study On The Resource Scheduling Methodes For Muliticast Streams In Heterogeneous Networks

Heterogeneous networks and multicast transmissions are key technologies for 5G wireless systems.The heterogeneous network can significantly improve the quality of the received signal by deploying the low-power node in the traditional macro cell and reducing the distance between the base station and the user.The multicast transmission will form a multicast group for users requesting the same data content,and the data will be transmitted to the group users at one time through the wireless broadcast channel,which can effectively improve the system spectrum efficiency.Multicast transmission in heterogeneous networks has the characteristics of high rate and large number of users,which is crucial to design a reasonable resource scheduling scheme to improve the overall performance of the system.To this end,this paper studies the heterogeneous network resource scheduling method for multicast streams.We first propose a joint allocation scheme for heterogeneous network channel resources and power resources for general multicast streams.With the goal of maximizing the user throughput of the multicast group,the resource allocation scheme is described as an optimization problem with the total transmit power of the system as a constraint.In order to reduce the complexity of the original problem,the non-smooth objective function is first converted into an equivalent constraint,and then the problem is decomposed into a channel allocation sub-problem and a power allocation sub-problem.A suboptimal solution for finding subproblems is designed for algorithms with lower complexity.The simulation results show that our resource allocation scheme can achieve higher multicast throughput than the existing scheme,and the iterative algorithm can converge quickly.On this basis,we study the resource joint allocation scheme for scalable video coding(SVC)multicast streams.The goal is to maximize the user throughput of an SVC multicast stream.We extend the resource allocation algorithm for general multicast streams,add the constraint relationship between the SVC multicast stream base layer and the enhancement layer,and design the resource allocation algorithm for base layer and the enhancement layer respectively.The final simulation verifies the convergence of the algorithm and its advantages in system throughput improvement.