Analysis And Solutions About Wireless Communication Interference In Train-ground For CBTC System

Because of radio interference caused interrupt operations by LINE 2 and LINE 5 of Shenzhen Metro. Communication security in train-ground for Communication Based Train Control system(CBTC) attached great importance to People in the industry.How to improve anti-interference ability of signal in the urban rail transit becomes the key of construction in rapid rail transit of city.In this paper, the IEEE802.11 wireless LAN standards are introduced. And LINE 2 of Shenzhen Metro adopted the IEEE802.11 g wireless LAN standard. Through the in-depth analysis of train ground wireless transmission, find the real cause of train emergency stop.This paper also has carried on the introduction to the current status of wireless communication for CBTC in the urban rail transit. It analysis communication mode of two kinds of signal system for the cross induction loop system and the wireless spread spectrum system.Because of radio interference, this paper offer 4 kinds of solutions, which improvement scheme of using 2.4G Hz,using scheme of 5.8G Hz, using LTE technology scheme, selection and application of special frequency in metro. It solute radio interference,and proved reliability and security of wireless communication.In order to deal with the interference of 2.4GHz, we established propagation model, and analyzed propagation and interference degree of different environment for 2.4 GHz and 5.8 GHz. In the laboratory and field, we verified the feasibility of the improved scheme of adaptive 2.4GHz band.In urban rail transit construction, equipment manufacturers, users and radio management shall be to ensure theapplication of wireless CBTC system as the primary goal.We should exerted the advantages of application of technical measures, management measures and policy management measures, soluted interference through fusion mode in wireless communication system, and ensure the safe operation of the train.