Optimization And Simulation Of Handover Algorithm In High-Speed Railway Environment Based On TD-LTE

The main subject of this paper is the handover algorithm in high speed railway environment. Due to the high speed and the bad channel, the handover performance is very poor. A new handover algorithm must be proposed to solve this problem and improve the quality of service.This paper firstly gives an introduction to basic theory of TD-LTE and high speed railway communication system. Then some basic researches, including the simulation platform and parameters, the filtering of received signal, the judgement of an algorithm, are made and designed to lay a foundation for the subsequent optimization.After the introduction of traditional A3event triggering handover algorithm, an optimization is made to meet the demand of high speed railway communication system. A new algorithm based on the statistical character of the delay of A3event triggering is proposed. Simulations are made to judge the performance of the optimized algorithm.At last, this paper creatively proposes a new handover algorithm which utilizes the speciality of high-speed railway. This algorithm is based on the GPS location of train and optimized soft handover. Simulations are also made to judge the performance of the algorithm.Compared with traditional A3event triggering handover algorithm, all the newly proposed algorithms have a better performance in high-speed railway communication system. It can be seen from the simulation results that the wireless link failure probability and pingpang effect is greatly reduced by these handover algorithms.