Patent ID: 11967242
Assignee: THE ISLAND RADAR COMPANY
Field: Transport (Mechanical engineering)
Classification: CPC G  B | IPC B  G

Claim 20:
21. A traffic control preemption system for signal lights at a signalized roadway intersection adjacent to but separated from a rail grade crossing, the system comprising:
a first train detecting element adjacent a railroad track passing through the rail grade crossing, the first train detecting element being a radar-based train detection sensor located at a distance from rail grade crossing, the radar-based train detection sensor being configured to determine a heading and speed of a detected train advancing toward the rail grade crossing; and
a controller that is operatively responsive to a detected train by the first train detecting element, and based upon the determined speed of the detected train the controller being configured to issue a preemption signal that interrupts a normal traffic signal routine for the signalized roadway intersection with at least a predetermined amount of warning time to clear vehicles from the rail grade crossing before the detected train arrives.