Experimental Analysis of DSRC for Radio Signaling at Grade Crossings

Despite the breakthroughs of wireless technology, only a few systems have been proposed for improving the safety at railroad crossings. We propose using and adapting the Dedicated Short-Range Communications (DSRC) protocol for railroad crossing protection to improve the safety of both trains and vehicles. This paper analyzes the radio frequency (RF) propagation channel and the DSRC system performance based on measurements at railroad crossings on a test track in wide-open spaces and artificial shadowing environments. These environments assimilate typical rural and urban settings. Our results show that the channel around railroad crossings has an approximately 3 to 5 dB lower Rician K factor and 2 higher path loss exponent when compared to typical Vehicle-to-Vehicle or Vehicle-to-Infrastructure environments; the RMS delay spread in the shadowing environment is similar to that of a tunnel or non-line of sight highway scenario. For the DSRC performance evaluation we use the packet error rate of the warning messages transmitted by the approaching train and received by cars near the railroad crossing. We find that warning messages are reliably received before the minimum notification distance in a wide-open space regardless of the train speed and in an artificial shadowing environment only when LoS condition provided.