Coordinated of multi-point and bi-casting joint soft handover scheme for high-speed rail

The high mobility of high-speed train brings great challenges to the current wireless communication, especially to the handover. How to reduce the interrupt time and enhance the handover performance is becoming a serious problem for high-speed rail (HSR). In this study, a coordinated of multi-point (CoMP) and bi-casting joint soft handover scheme for HSR is proposed, which is based on long-term evolution network architecture, and without any change to the existing network and the train. In the scheme, CoMP is used on air interface and bi-casting is used on S1 interface. With the binding triggering of CoMP and bi-casting, only one suit of signalling is needed and the system complexity is much simplified. Meanwhile, as much handover related information is stored in corresponding entity during the joining process of CoMP and bi-casting, the handover process is much simplified and converted into update of serving eNodeB. Compared with traditional handover scheme, it can be seen from theoretical analysis and simulation results that the handover delay is reduced remarkably and the handover performance is improved greatly.