The Study And Simulation Of Handover Algorithm In TD-LTE Under High-Speed Railway Enviorment Based On NS2

With the development of the LTE (Long Term Evolution) technology, the LTE communication technologies in railway communication system present a good application prospect. How to meet the requirement of the signal quality in the environment of the special line information transmission, how to send the data without dropping packet, and to meet the customer demand for the data rates has important meaning to be researched. As the development of high-speed railway, the handover algorithm in the high-speed environment with the LTE system is necessary to be purposed.This paper proposes the effective handover algorithm in the environment of high-speed railway. The simulation tools NS2 is chosen to test the quality of the algorithm. The paper will introduce the network architecture scene in the environment of high-speed railway and the physical layer in the TD-LTE. To improve the quality of the network, the effective handover algorithm is studied. The realization in NS2 simulation of handover algorithm is introduced and the simulation result is shown in the paper.First of all, the rational network design is purposed to combine with the complex topography environment. The context of the network design includes the antenna configuration, RRU number, the area radius and length of the overlap area. The environment of high-speed railway contains plain, mountain and tunnel. In the paper, the network plan analysis based on the three circumstances is put forward.Secondly, the reference of the physical strength RSRP is researched and emulated. The value of the RSRP is important for the study of the handover algorithm. In the paper, the value of the RSRP is emulated based on the TD-LTE system. The simulation appears the modulation and demodulation of OFDM symbol with the high-speed channel module. And then, the paper proposes the quick handover mechanism and the advanced handover algorithm based on the TD-LTE. The protocol stack is simulated in the NS2. The handover algorithm quality is proved by the NS2 software.Finally, with the simulation result of the handover algorithm, effective handover mechanism is suggested and the rational network design scheme based on the high-speed railway environment is proposed.