Quasi-Full-Duplex Wireless Communication Scheme for High-Speed Railway

Full-duplex, massive antenna and higher frequency bands are core technologies of the fifth generation (5G) wireless communications to boost the throughput to satisfy the future explosively increasing demands of traffic volume. Unfortunately, the implementation of full-duplex is badly limited by the severe self-interference. In this paper, we propose a novel quasi-full-duplex scheme on the basis of separate transceiver arrangement and massive antenna beamforming to achieve future high reliable and efficient professional railway wireless communication systems. To obtain accurate direction of arrival (DOA) of the desired user for beamforming, real-time feedback link and novel reference signal (RS) distribution are designed to adapt to high-speed scenario. The theoretical analysis and numerical simulations demonstrate that the proposed scheme can dramatically improve the spectrum efficiency and transmission reliability, except for the scope nearby the eNodeB where the receiver of eNodeB is overwhelmed by its local signal. The complementary method that employs power control and higher frequency bands has settled this problem entirely.