In the GSM-R (GSM for Railways) mobility management technology, handover is the crucial factor to maintain high reliability and validity of mobile communication. However in high-speed movement scenario where shorter handover latency is required, the traditional handover scheme which has been adopted in the GSM network could no longer guarantee high quality performance and results in higher probability of handover failure as a consequence. In order to solve such problem, we propose an innovative handover scheme based on dual-antenna technology for GSM-R network. The proposed scheme modulates the frame structure of Traffic Channel (TCH) in order to send measurement report more quickly and adopts more complicated signaling procedure to achieve seamless handover. Simulation results show that interruption time in the proposed scheme is effectively reduced compared with the conventional handover scheme and call dropping rate is also acceptable when the train speed achieves 500km/h. Therefore the proposed dual-antenna handover scheme guarantees better service quality in high-speed scenario.