Warning horn control system, radar system, and method

• US 9,019,115 B2
• Filed: 07/02/2010
• Issued: 04/28/2015
• Est. Priority Date: 07/02/2010
• Status: Active Grant

• Current Assignee: Alstom Holdings (Alstom SA)
• Original Assignee: General Electric Company
• Inventors: Ballinger, Forrest H.
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): POINT, RUFUS C
• Application Number:
  US12/830,081
• Publication Number:
  US 20120001767A1
• Time in Patent Office: 1,761 Days
• Field of Search: 340/901, 340/905, 340/435, 340/902, 340/686.6, 340/903, 367/27, 367/40, 246/473.1, 246/292, 246/294
• US Class Current: 340/686.6
• CPC Class Codes: B61L 29/24 Means for warning road traffic that a gate is closed or closing, or that rail traffic is approaching, e.g. for visible or audible warning
• CPC Class Codes: G01S 13/04 Systems determining presence of a target based on relative movement of target G01S13/56
• CPC Class Codes: G01S 13/18 wherein range gates are used

Abstract

There is provided a radar system that includes an emitter system (e.g., an antenna), configured to emit electromagnetic pulses and detect electromagnetic pulses, and a reflection target, placed opposite the emitter system. The emitter system and the reflection target define an area of interest. A controller is configured to identify a reflection from the reflection target and, if the reflection is not identified, to stop sending a radar check signal. The radar system may be part of a warning horn control system, where the radar check signal is used as a control input for activating a warning horn.

Claims

1. A radar system, comprising:

an emitter system configured to emit an emitted electromagnetic pulse and detect a reflected electromagnetic pulse;

a reflection target configured to be disposed opposite the emitter system to define an area of interest, the reflection target configured to reflect the emitted electromagnetic pulse as the reflected electromagnetic pulse;

a timer configured to determine a time window based at least in part on a time delay between emission of the emitted electromagnetic pulse by the emitter system and detection of the reflected electromagnetic pulse by the emitter system between the reflection target and the emitter system; and

a controller configured to generate a radar check signal indicative of an absence of a variable target in the area of interest, the controller configured to generate the radar check signal responsive to detecting the reflected electromagnetic pulse during the time window.

2. The radar system of claim 1, wherein the reflection target includes an advance warning sign.

3. The radar system of claim 1, wherein the reflection target is includes a dedicated passive target reflector.

4. The radar system of claim 1, further comprising a train detection system configured to stop providing a train-detection check signal when a train is approaching a crossing.

5. The radar system of claim 4, further comprising:

a warning system configured to generate a warning of the train approaching the crossing; and

a logic control circuit configured to activate the warning system responsive to both the radar check signal and the train-detection check signal not being generated.

6. The radar system of claim 1, wherein the timer comprises logic configured as a timing gate.

7. The radar system of claim 1, wherein the timer is configured to identify a secondary reflection of the emitted electromagnetic pulse off the variable target between the emitter system and the reflection target.

8. The radar system of claim 7, wherein the controller is configured to identify whether the variable target between the emitter system and the reflection target is approaching a crossing based, at least in part, on timing of the secondary reflection.

9. The radar system of claim 8, wherein the controller is configured to stop generating the radar check signal responsive to identifying the variable target approaching the crossing, even if the reflected electromagnetic pulse is received from the target reflector during the time window.

10. The radar system of claim 1, wherein the variable target comprises a truck, a car, a pedestrian, a bicyclist, or any combination thereof.

18. The radar system of claim 1, wherein the timer is configured to determine the time window such that the time window begins at a first time and ends at a second time, the first time occurring subsequent to emission of the electromagnetic pulse by the emitter system.

19. The radar system of claim 1, wherein the timer is configured to determine the time window by calculating a time that the reflected electromagnetic pulse is to be received at the emitter system based on a distance between the emitter system and the reflection target and by extending the time window around the time that is calculated.

11. A warning control system comprising a radar system configured to determine a time window based at least in part on a time delay between emission of an emitted electromagnetic pulse and detection of a reflected electromagnetic pulse from a reflection target, the radar system also configured to generate a radar check signal responsive to detecting the reflected electromagnetic pulse from the reflection target within the time window.

12. The warning control system of claim 11, wherein the radar system is configured to stop providing the radar check signal responsive to determining that a variable target is approaching a crossing, even if the reflected electromagnetic pulse received within the time window.

13. The warning control system of claim 11, further comprising a train detection system configured to generate a train-detection check signal responsive to determining that a train is not approaching a crossing and to stop generating the train-detection check signal responsive to determining that the train is approaching the crossing.

14. The warning hem-control system of claim 13,

wherein the radar system is configured to activate a warning system responsive to both the radar check signal and the train-detection check signal not being generated.

15. A method comprising:

emitting a first pulse into a region with an emitter system portion of a radar system;

determining a time window based at least in part on one or more of a time delay that the first pulse travels from the emitter system portion to a reflection target or a time delay that a reflected pulse from the reflection target travels to the emitter system portion from the reflection target; and

generating a radar check signal indicative of an absence of a variable target between the emitter system portion and the reflection target responsive to the reflected pulse being detected within the time window.

16. The method of claim 15, further comprising:

stopping generation of the radar check signal responsive to the reflected pulse one or more of not being detected or being detected outside of the time window.

17. The method of claim 15, further comprising arming a warning system responsive to the radar check signal no longer being generated.

20. A radar system comprising:

a controller configured to determine a time window that occurs subsequent to transmission of a first electromagnetic pulse from an emitter system toward a reflection target, the emitter system and the reflection target spatially separated from each other to define an area of interest,

wherein the time window is based on a time delay that includes propagation of the first electromagnetic pulse from the emitter system to the reflection target without being reflected off one or more variable targets in the area of interest between the emitter system and the reflection target, reflection of the first electromagnetic pulse off the reflection target as a reflected electromagnetic pulse, and propagation of the reflected electromagnetic pulse from the reflection target to the emitter system without being reflected off the one or more variable targets in the area of interest between the emitter system and the reflection target,

wherein the controller also is configured to deactivate a warning system for a crossing between plural vehicle routes by generating a radar check signal responsive to the reflected electromagnetic pulse being received within the time window.

21. The radar system of claim 20, wherein the controller is configured to determine the time window such that the time window begins at a first time that is temporally separated from the transmission of the first electromagnetic pulse from the emitter system.

22. The radar system of claim 20, wherein the controller is configured to identify presence of the one or more variable targets in the area of interest between the emitter system and the reflection target responsive to the reflected electromagnetic pulse being received outside of the time window.

23. The radar system of claim 22, wherein the controller is configured to activate the warning system responsive to identifying the presence of the one or more variable targets within the area of interest.

24. The radar system of claim 20, wherein the controller is configured to identify a failure of the emitter system responsive to not detecting the reflected electromagnetic pulse within the time window.

25. The radar system of claim 20, wherein the controller is configured to activate the warning system responsive to both:

the reflected electromagnetic pulse not being detected within the time window, and

one or more of a train detection system detecting a train approaching the crossing or a failure of the train detection system.