Train-to-wayside wireless communication in tunnel using ultra-wide-band and time reversal

The capabilities of ultra-wide-band (UWB) technology make it a viable candidate for fourth generation wireless communication. This paper proposes the use of UWB radio technology and time-reversal (TR) technique for underground train-to-wayside communication systems. UWB technology has the potential to offer simultaneous ground-to-train communication, train location and obstacle detection in front of the trains. Time-reversal channel prefiltering facilitates signal detection and helps reducing interference. Thus, UWB–TR combination provides a challenging, economically sensible, as well as technically effective alternative solution to existing signaling technologies used in urban transport systems. This paper concentrates on the communication function and reports simulation and measurement performance evaluation of such combinations, respectively in a deterministic tunnel channel model and in real tunnel environments. A new approach is also proposed to ensure multiple access (MA) communication using modified-orthogonal waveforms.