Research On Vertical Handoff Algorithm For Dense Heterogeneous Networks

With the development and innovation of network technology,a single network coverage will be unable to meet the needs of users for diverse services.Therefore,in order to adapt to the increasing demand of users for network services,the future network architecture will certainly develop toward the direction of multi-network coexistence and high-speed computing.In order to ensure the quality of service of users in the coverage of multiple networks,vertical handover has extremely important research and learning significance as a means to realize real-time and reasonable selection for users between networks of different types and different architectures.For the vertical handover technology under different network coverage,both academics and industry have proposed some effective and unique solutions,but there are few researches on vertical handover algorithms in dense heterogeneous network coverage scenarios,and traditional The heterogeneous network vertical handover algorithm often ignores the mobile characteristics of the users,and thus the traditional vertical handover algorithm cannot be applied to the vertical handover under the multi-network coverage condition in the future fast moving scene.In view of the shortcomings of the above traditional heterogeneous network vertical handover algorithm,this paper proposes a vertical handover algorithm suitable for dense heterogeneous network coverage based on the user's mobile characteristics.The whole vertical handover process is subdivided into an alternative network selection process and a network switching time determination process,and corresponding solutions and calculation formulas are respectively given for the above two sub-processes.Firstly,in the alternative network selection process,a network switching function based on the parameters of the alternative network and different service users and service types' priorities is proposed for the more common dense network architecture scenarios in the future network,and will be approximated in the function construction process.The idea and the method of gray level analysis are combined with approaching thought reasonable adaptability,and the purpose of improving the rationality and effectiveness of network selection is achieved on the basis of ensuring certain algorithm complexity.Then,through the fuzzy logic,the user's own moving speed and moving direction under the coverage of multiple heterogeneous networks are included in the calculation process of the network switching time,and the different moving speed levels are divided to predict the user's current difference.The required service time within the network coverage is constructed,and the network switching time point set is calculated based on the obtained predicted service time.Finally,the alternative network switching selection function obtained above is combined with the network switching time point set to obtain a heterogeneous network vertical handover algorithm which is suitable for the heterogeneous network coverage and considers the user's own mobile characteristics.Simulation experiments show that the heterogeneous network vertical handover algorithm proposed in this paper is better than the comparison algorithm for the average number of handovers,average blocking rate and QoS of different service users and different service types under the same conditions.Therefore,under the dense network coverage,the heterogeneous network vertical handover algorithm proposed in this paper can effectively improve the validity and accuracy of network handover and improve the network service quality of users based on certain algorithm complexity.