An On-Vehicle Dual-Antenna Handover Scheme for High-Speed Railway Distributed Antenna System

Distributed antenna technology, as one of the important next-generation wireless communication technologies, has aroused extensive attention. The technology has been applied in high-speed movement environment. Due to the high density coverage of distributed antennas, almost anywhere in the area has line-of-sight (LOS) to reach at least one fixed antenna. However it may correspondingly result in smaller overlap between adjacent cells and higher probability of handover failure in high-speed movement scenario. In order to solve these problems, this paper proposes a novel handover scheme based on on-vehicle dual-antenna for high-speed railway distributed antenna system (DAS). On-vehicle antennas which collaborate each other, are mounted on the top of high-speed train (the one is in the front-end and the other is in the rear-end). The proposed scheme utilizes distributed transceivers and centralized processing technology. The numerical analysis results show that the novel scheme can pre-trigger handover appropriately, guarantee the higher handover success rate, and increase the system throughput by around 50%. In addition, the scheme is feasible and easy to be implemented.