Wireless communication for heavy haul railway tunnels based on distributed antenna systems

摘要

Radio-over-fiber (RoF) technology can improve reliability and quality of service (QoS) of railway communication systems effectively. This paper studies directional antenna radiating same direction and intercross base station redundant network these two coverage strategies of RoF in long heavy haul railway tunnels (more than 1 km). As RAUs (remote antenna unit) deployed in long tunnels, according to different coverage strategies, the number of RAUs is different, this will lead various handover mechanisms. Based on the channel modeling of simulator in this paper, coverage efficiency (power consumption of unit distance in tunnel) handover trigger probability and outage probability are adopted to compare the performance of these two coverage strategies. It can be concluded that when using directional antenna radiating same direction, due to the longer radiate distance R, it has better coverage efficiency, and the trigger probability almost reached 100% once entered the overlapping area, and the handover outage probability is clearly lower than using intercross base station antenna network, even if the train is fast.