Research On Resource Scheduling Model And Optimization Algorithm In Wireless Virtualized Networks

In response to the rapidly growing demand for data traffic and diversification of business types,wirless network virtualization technology has received wide attention from acadamia and industry.Based on Software Defined Network and Network Function Virtulization,wirless network virtualization integrates wireless network resources into a unified resource pool and dynamically allocates resource according to the requirement of different scenarios,so as to form independent and directed virtual networks.The virtual network can reduce the network operation and maintenance costs while improving the utilization of network resource.However,due to the limited physical network,how to effectively allocate network resource for each virtual network and meet the QoS requirement is crucial to the virtual netwok implement.This paper focuses on the resource allocation in wireless virtual networks.The main contents and innovations of this paper are summarized as follows:1.Aiming at the problem of spectrum resource sharing between access and backhaul link of each virtual network when in-band self-backhaul is adopted by small base stations,a virtual resource allocation utilizing Lyapunov for wireless self-backhaul network is proposed.Firstly,a joint radio access resources and backhaul algorithm is deployed to maximize the virtual network utility under certain practical preconditions,i.e.the network queue stability,the minimum average data rate for each virtual network and the capacity constraint of the backhaul link.Secondly,a real-time scheduling algorithm based on the current channel state and queue state is designed by using Lyapunov optimization.Finally,it's solved by Lagrange duality algorithm and particle swarm algorithm based on similarity random variation.The simulation results show that the proposed method can effectively improve the total average revenue of virtual network while guaranteeing the queue stability.2.In order to solve the unreasonable virtual resource allocation caused by the uncertainty of service and delay of information feedback in wireless virtualized networks,this paper proposes an online adaptive virtual resource allocation algorithm based on prediction.Firstly,a utility of virtual networks minimization is studied by jointly allocating the time-frequency resources and buffer space,while guaranteeing the overflow probability of each virtual network.Secondly,considering the different demand of virtual networks to different resources,this paper designs a resource dynamic scheduling mechanism with multiple time scales,in which the reservation strategy of buffer space is realized based on the prediction information in slow time scale and the virtual networks are sorted according the overflow probability derived by the large deviation principle and dynamically schedules the time-frequency resources in fast time scale,so as to meet the service demand.Simulation results show that the algorithm can effectively reduce the bit loss rate and improve the utilization of physical resources.