Because of different system capacities of base station(BS)or access point(AP)and ununiformity oftraffic distribution in different cells,quantities of new call users may be blocked in overloaded cell incommunication ho...Because of different system capacities of base station(BS)or access point(AP)and ununiformity oftraffic distribution in different cells,quantities of new call users may be blocked in overloaded cell incommunication hot spots.Whereas in some neighboring under-loaded cells,bandwidth may be superflu-ous because there are only few users to request services.In order to raise resource utilization of the wholeheterogeneous networks,several novel load balancing strategies are proposed,which combine the call ad-mission control policy and multi-hop routing protocol of ad-hoc network for load balancing.These loadbalancing strategies firstly make a decision whether to admit a new call or not by considering some param-eters like load index and route cost,etc.,and then transfer the denied users into neighboring under-load-ed cell with suiplus channel according to optimum multi-hop routing algorithm.Simulation results showthat the proposed load balancing strategies can distribute traffics to the whole heterogeneous wireless net-works,improve the load balance index efficiently,and avoid the call block phenomenon almost absolutely.展开更多
This paper investigates channel allocation and power control schemes in OFDM-based multi-hop cognitive radio networks.The color-sensitive graph coloring(CSGC) model is viewed as an efficient solution to the spectrum a...This paper investigates channel allocation and power control schemes in OFDM-based multi-hop cognitive radio networks.The color-sensitive graph coloring(CSGC) model is viewed as an efficient solution to the spectrum assignment problem.The model is extended to combine with the power control strategy to avoid interference among secondary users and adapt dynamic topology.The optimization problem is formulated encompassing the channel allocation and power control with the interference constrained below a tolerable limit.Meanwhile,the proposed resource allocation scheme takes the fairness of secondary users into account in obtaining the solution of optimization.Numerical results show that the proposed strategy outperforms the existing spectrum assignment algorithms on the performance of both the network throughput and minimum route bandwidth of all routes,as well as the number of connected multi-hop routes which implies the fairness among secondary users.展开更多
基金Supported by the National Natural Science Foundation of China (No. 60672059, 60496315 )the National High Technology Research and Development Programme of China (No.2006AA01Z233)
文摘Because of different system capacities of base station(BS)or access point(AP)and ununiformity oftraffic distribution in different cells,quantities of new call users may be blocked in overloaded cell incommunication hot spots.Whereas in some neighboring under-loaded cells,bandwidth may be superflu-ous because there are only few users to request services.In order to raise resource utilization of the wholeheterogeneous networks,several novel load balancing strategies are proposed,which combine the call ad-mission control policy and multi-hop routing protocol of ad-hoc network for load balancing.These loadbalancing strategies firstly make a decision whether to admit a new call or not by considering some param-eters like load index and route cost,etc.,and then transfer the denied users into neighboring under-load-ed cell with suiplus channel according to optimum multi-hop routing algorithm.Simulation results showthat the proposed load balancing strategies can distribute traffics to the whole heterogeneous wireless net-works,improve the load balance index efficiently,and avoid the call block phenomenon almost absolutely.
基金Supported by the National Natural Science Foundation of China(No.61461006)the Guangxi Province Natural Science Foundation(No.2013GXNSFBA19271)
文摘This paper investigates channel allocation and power control schemes in OFDM-based multi-hop cognitive radio networks.The color-sensitive graph coloring(CSGC) model is viewed as an efficient solution to the spectrum assignment problem.The model is extended to combine with the power control strategy to avoid interference among secondary users and adapt dynamic topology.The optimization problem is formulated encompassing the channel allocation and power control with the interference constrained below a tolerable limit.Meanwhile,the proposed resource allocation scheme takes the fairness of secondary users into account in obtaining the solution of optimization.Numerical results show that the proposed strategy outperforms the existing spectrum assignment algorithms on the performance of both the network throughput and minimum route bandwidth of all routes,as well as the number of connected multi-hop routes which implies the fairness among secondary users.