Topology discovery for linear wireless networks with application to train backbone inauguration

A train backbone network consists of a sequence of nodes arranged in a linear topology. A key step that enables communication in such a network is that of topology discovery (TD), or train inauguration, whereby nodes learn in a distributed fashion the physical topology of the backbone network. While the current standard for train inauguration assumes wired links between adjacent backbone nodes, this work investigates the more challenging scenario in which the nodes communicate wirelessly. The key motivations for this desired switch from wired TD to wireless one are the flexibility and capability for expansion and upgrading of a wireless backbone. The implementation of TD over wireless channels is made difficult by the broadcast nature of the wireless medium, as well as by fading and interference. A novel TD protocol is proposed, which overcomes these issues and requires relatively minor changes to the wired standard. The protocol is shown via analysis and numerical results to be robust to the impairments caused by the wireless channel, including interference from other trains.