An Enhanced Cost Efficient Scheduling Algorithm For Dense Wireless Network

In order to meet explosive data traffic increased recently,the wireless network is more and more dense.To address this issue,a large amount of low power nodes can be deployed to improve network performance.However,there emerge some new problems and challenges as well,and how to schedule the resource cost-efficiently in dense network is one of them.This thesis introduces the dense wireless networks,including the concept and properties of dense wireless networks.Then,this thesis introduces the current criteria for evaluate energy efficiency,and pointed out the shortcomings when it applies in dense networks.As a result,the cost-efficiency is introduced to depict the system performance more precisely.Finally,the definitions of cost-efficiency,power model and cost model are introduced.Cost-efficient resource scheduling algorithms are proposed in the dense wireless network with ideal and non-ideal backhauls.The main research work and innovations are given in as follows:1)For heterogeneous hierarchical dense wireless networks with ideal backhaul,a user driving resource allocation algorithm is proposed,including band division,resource allocation and power control.Band division strategies will divide band into three parts:the macro base station-specific resources,resources shared by macro base stations and low-power node,and low power node dedicated resources.The size of resource block is varying as the network load.This band division strategy combines the advantages of fully multiplexing and completely orthogonal frequency division.In this thesis,the proposed resource allocation algorithm schedules the resources based on transmission rate of the user.If the user’s traffic needs is large,the orthogonal resources are used.If the user’s traffic needs is small,the reused resources are used.The disadvantage of complex calculations with a soft frequency reuse is offset by the proposed resource allocation algorithm.The object of power control optimization is the cost efficiency,and the need of user is meet as well.2)For heterogeneous hierarchical dense wireless networks with non-ideal backhaul,a cost-efficient,resource allocation algorithm is proposed,including band division and resource allocation.Band division strategies will divide band into five parts:the macro base station-specific resources,resources shared by macro base stations and low-power node,low power node dedicated resources,in-band backhaul resource and out-band backhaul resource.The size of resource block is varying as the network load,user business and the forms of backhaul.This band division strategy combines the advantages of fully multiplexing and completely orthogonal frequency division.When the resource block is backed,the base station will adjust the size of in-band resource block based on the proportion of backhaul traffic and non-backhaul traffic.This band division takes the different costs of the different backhaul resources into consideration.The resources allocation between the access resources and backhaul resources is optimized by maximizing the system cost efficiency.