Design aspects and performance evaluation of ATCS mobile data link

The Mobile Data Link (MDL) System for the North American Advanced Train Control System (ATCS) is proposed and analyzed with respect to the ATCS preliminary requirements. Design aspects of mobile data radios are discussed to point out the hardware limitations due to DOC (US Department of Communications) and FCC (US Federal Communications Commission) regulations and technologies. The propagation characteristics of the channel are investigated. The RF field strength coverage of a base station predicted for urban, suburban, quasiopen, and open is given. Multipath fading models are also given. The probabilities of success for a single try as a function of received signal levels are presented for different trains' speeds. System bit error rates (BER) for different cases are also shown. The use of Reed-Solomon codes for forward error correction is also included to show the improvement of the system performance.<
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