Research On Vertical Handoff And Resource Allocation Algorithms In Heterogeneous Wireless Networks

With the rapid development of wireless communication and information technology,the network system structure is becoming more and more complex,and users are facing the coexistence of multiple networks.Better implementation of heterogeneous network fusion technology is one of the focuses of the next-generation network technology.As a part of the key technologies for heterogeneous wireless network convergence,both the vertical handover and resource allocation guarant user the Qo S and resources the reasonable distribution,which are of great significance to the development of heterogeneous wireless networks.However,the existing vertical handover algorithms still have problems of high handoff times and high reversal rate(high ping-pong effect).To tackle these problems,a new vertical handover algorithm based on grey correlation analysis and improved entropy weight method had been proposed here.In detail,the entropy weight method is first used to calculate the objective weights of the network attributes,and to obtain the comprehensive weights of the network combining with the subjective weights.After that,the gray correlation degree of the candidate networks is obtained through the gray correlation sending,and the relevant networks are ranked.Finally,the network with the largest gray correlation degree is taken as the best candidate network.In which,a threshold mechanism is setting to determine the difference between the correlation degree of the best candidate network and the connection degree of the current terminal connection network.As a result,if the difference is greater than the threshold value,the vertical handover will be done.Comparing with the simulation results derived from GRA,SAW,MEW,Topsis and AHP,the number of handoffs required is effectively reduced,and reduce the handover inversion phenomenon,and the ping-pong effect are decreased at the same time with our proposed algorithm.In addition,with growing business and users,the wireless resources are becoming increasingly precious and scarce.Among them,the bandwidth and power,the two important resources of heterogeneous wireless network communications,become more and more stretched.In view of the above problems,a heterogeneous wireless network resource allocation algorithm based on the Staceklberg game had been proposed forthe heterogeneous cellular wireless network scenario composed of small base stations(SBS)and macro base stations(MBS).The MBS and SBS resource allocation problem is regarded as a Stackelberg game.A price mechanism is introduced to establish a game model.MBS plays the role of Stackelberg leader and determines pricing strategies based onSBS user behavior and bandwidth power requirements in order to maximize their own revenue.SBS,acting as a follower of Stackelberg,needs to purchase the appropriate amount of power and bandwidth resources from MBS to provide the users the data traffic.With ensuring users the Qo S,they pursue their own maximum benefits at the same time.The proposed game model verifies the existence of Stackelberg equilibrium and has a game equilibrium solution.Simulation results show that compared with other existing algorithms.effectively improves.The utilization of bandwidth and power resources and the utility of the system are both improved effectively with out propsosed algorithm.