Train location and control using spread spectrum radio communications

A system for controlling a train along a fixed track system via spread spectrum, wireless communication links, comprising:

• a control station comprising a control station wireless RF radio set for RF communication with said trackside radio sets, said station further comprising means for generating train control command and spread spectrum encoding means for encoding said command onto RF signals transmitted by said control station radio set;
• a plurality of trackside wireless RF radio sets located in spaced relation at fixed, predetermined positions relative to said track system;
• at least one train-mounted wireless RF radio set located on said train;
• wherein said trackside radio sets comprise means for relaying said encoded RF signals transmitted by said control station radio set to said train-mounted radio set, said trackside radios are dispersed over said track system so as to enable communication between said control station and said train over said track system, and said train-mounted radio set comprises means for decoding said commands and providing said decoded commands to an on-board train control system.

A vehicle location and control system employing spread spectrum radio communications, comprising:

• a plurality of wayside wireless RF radio sets located at predetermined fixed locations throughout a route system traveled by said vehicle;
• at least one vehicle-mounted wireless RF radio set located on each vehicle;
• a control station comprising a control station wireless RF radio set, and means for generating vehicle movement control signals;
• each said wayside, vehicle-mounted and control station radio set comprising spread spectrum modulating and demodulating means so as to provide the capability of transmitting and receiving spread spectrum encoded messages, and wherein said radio sets comprise a collection of spread spectrum radio sets participating in a time-synchronized, time division multiple access (TDMA) communications network, wherein said vehicle control commands are relayed from said control station to said vehicle radio set via one or more of said wayside radio sets;
• range determination means for determining a range location of said vehicle in relation to one or more of said wayside radio sets, said means employing time of arrival detection and processing means to determine said range location from radio signal transmissions between said vehicle-mounted and wayside radio sets;
• and
• position determining means for determining an absolute position of said vehicle from said range location and said predetermined positions of said wayside radios.