LAUSR

Abstract With the recent rapid improvement of wireless communication technology, wireless network gains increasing interest as a train backbone in order to provide the passenger service as well as the original real-time control duties. To use the wireless network as a train backbone, however, the existing standard protocol, IEC Std. 61375 Train Communication Network(TCN), needs to be modified to reflect the wireless-specific characteristics because it was originally designed for the wired network such as switched Ethernet. The train topology discovery protocol(TTDP) that provides automatic network reconfiguration is one of the key TCN protocols to be modified to support a wireless train bus. This paper proposes a modified topology discovery protocol that can be used for a train-wide wireless LAN. Proposed protocol finds the bus topology based on the radio signal strength with maintaining the existing standards and controls the transmit signal power to avoid overhearing problem in wireless network. The time bound to build network topology using the proposed protocol is also estimated by computer simulation.