Train crossing modeling based on measurements and best numerical approximation in subway tunnels  

作　　者：官科 Zhong Zhangdui Ai Bo Cesar Briso-Rodriguez 

机构地区：[1]State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University [2]Escuela Universitaria de Ingenieria Tecnica de Telecomunicacion,Universidad Politecnica de Madrid

出　　处：《High Technology Letters》2013年第2期182-189,共8页高技术通讯（英文版）

基　　金：Supported by the National Natural Science Foundation of China(No.60830001);Program for New Century Excellent Talents in University(No.NCET-09-0206);the Key Project of State Key Lab.of Rail Traffic Control and Safety(No.RCS2008ZZ006);Program for Changjiang Scholars and Innovative Research Team in University(No.IRT0949);the Project of State Key Lab.of Rail Traffic Control and Safety(No.RCS2008ZT005)

摘　　要：Communication based train control systems （CBTC） must work even in the worst situation-- train crossing. This paper models the propagation characteristics in one of the most common and piv- otal scenarios--train crossing in subway tunnels which is rarely mentioned in previous publications. Firstly, measurements for train crossing scenario at 2.4 GHz in a real subway line in Madrid have been made. The field measurement is the most reliable way to reveal the propagation characteristics involving shadowing effect and fast fading. Moreover, to precisely describe the fast fading distribu- tion and eliminate the inevitable weak points of traditional fitting way, a best numerical approxima- tion method using Legendre orthogonal polynomials has been proposed. Comparisons show that this method works better and is of greater physical significance. Finally, a complete statistical model is given and all the coefficients can be applied by system designers for the link and system level simu- lations.Communication based train control systems(CBTC) must work even in the worst situation—train crossing.This paper models the propagation characteristics in one of the most common and pivotal scenarios—train crossing in subway tunnels which is rarely mentioned in previous publications.Firsdy,measurements for train crossing scenario at 2.4 GHz in a real subway line in Madrid have been made.The field measurement is the most reliable way to reveal the propagation characteristics involving shadowing effect and fast fading.Moreover,to precisely describe the fast fading distribution and eliminate the inevitable weak points of traditional fitting way,a best numerical approximation method using Legendre orthogonal polynomials has been proposed.Comparisons show that this method works better and is of greater physical significance.Finally,a complete statistical model is given and all the coefficients can be applied by system designers for the link and system level simulations.

关 键 词：communication based train control systems （CBTC） measurement train cross-ing TUNNEL propagation modeling 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]