Theory Analysis of the Handover Challenge in Express Train Access Networks (ETAN)

To handle the handover challenge in Express Train Access Networks (ETAN), mobility fading effects in high speed railway environments should be addressed first. Based on the investigation of fading effects in this paper, we obtain two theoretical bounds: HO-Timing upper bound and HO-Margin lower bound, which are helpful guidelines to study the handover challenge today and in the future. Then, we apply them to analyze performance of conventional handover technologies and our proposal in ETAN. This follow-up theory analyses and simulation experiment results demonstrate that the proposed handover solution can minimize handover time up to 4 ms (which is the fastest one so far), and reduce HO-Margin to 0.16 dB at a train speed of 350 km/h.