Mobile data link field trials: an evaluation for ATCS

Results of mobile-data-link field trials conducted in Canada are reported. These trials were initiated to evaluate feasibility of digital transmissions for the advanced train control system (ATCS). The trials were conducted using commercially available equipment in the 150, 400, and 800 MHz band. Two extremes, flat and hilly terrain conditions, were chosen to provide good and difficult propagation conditions. From the recorded data error files were created and these files were analyzed for probability of error. The signal envelope recorded is analyzed for variations of input signal, i.e. signal strength in terms of dB above 1 μV. This signal is related to the measured error rates. The probability of error is then plotted against signal strength for several radios and vehicular speeds