Research and Application of Tunnel Emergency Positioning System Based on Beidou#br#
MA Tianyu1, ZHANG Lixian1, SU Zhou2*
(1. Yunnan Provincial Highway Management Corps (Comprehensive Transportation Development Center),
Kunming, Yunnan, 650031, 2. Yunnan Science Research Institute of Communication & Transportation Company
Limited, Kumming, Yunnan, 650051)
