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A Radar Vehicle Detection System for Four-Quadrant Gate Warning Systems and Blocked Crossing Detection

Document Series
Technical Reports
Thomas N. Hilleary
Report Number
Subject Grade Crossing Technology, Highway-Rail Grade Crossing Warning Systems, Highway-Rail Grade Crossings, Signal and Train Control
Microwave radar, vehicle detection, Wavetronix, four-quadrant gate, blocked railroad crossing, exit gates, obstacle detection, IODS, island radar,

The Wavetronix Matrix Radar was adapted for use at four-quadrant gate railroad crossings for the purpose of influencing exit gate behavior upon the detection of vehicles, as an alternative to buried inductive loops. Two radar devices were utilized, operating collaboratively, in order to realize a fully redundant system. Performance variables including vehicle size and location, vehicle occlusion, and radar positioning were evaluated, along with sensitivity to rain, snow, and other environmental conditions. Recommendations for utilization of the radars in conjunction with popular crossing warning system controllers are provided. Also included is a means for detecting vehicles that are stopped, stored, or deliberately placed in the crossing island, and rapidly communicating that information across cellular, PTC, ITCS, and ACSES, and other data networks.

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Last updated: Thursday, January 10, 2013