Radar apparatus and alignment sensor

• US 20080278386A1
• Filed: 05/07/2007
• Published: 11/13/2008
• Est. Priority Date: 05/07/2007
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Granat, Stanley M., Hall, Richard R.
• Granted Patent: US 7,884,772 B2
• Time in Patent Office: Days
• US Class Current: 343/703
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 2013/0245 Radar with phased array antenna
• CPC Class Codes: G01S 7/4026 Antenna boresight
• CPC Class Codes: G01S 7/403 in azimuth, i.e. in the horizontal plane
• CPC Class Codes: G01S 7/4034 in elevation, i.e. in the vertical plane
• CPC Class Codes: H01Q 1/1235 Collapsible supports; Means for erecting a rigid antenna
• CPC Class Codes: H01Q 3/02 using mechanical movement of antenna or antenna system as a whole
• CPC Class Codes: H01Q 3/267 Phased-array testing or checking devices

Abstract

A radar apparatus including: a radar antenna array; and, a sensor for detecting a relative distortion of at least one portion of the radar antenna relative to at least one other portion of the radar antenna array.

Claims

1. A radar apparatus comprising:

a radar antenna array; and

,

a sensor for detecting a relative distortion of at least one portion of the radar antenna relative to at least one other portion of the radar antenna array.

2. The radar apparatus of claim 1, wherein the sensor comprises at least one interferometer.

3. The radar apparatus of claim 1, wherein the sensor comprises a plurality of interferometers.

4. The radar apparatus of claim 1, further comprising:

at least one source of electromagnetic radiation emissions; and

a plurality of reflectors coupled to the antenna and positioned to reflect emission from the at least one source to the at least one sensor.

6. The radar apparatus of claim 1, wherein the sensor comprises a plurality of load cells coupled to the antenna.

7. The radar apparatus of claim 1, wherein the sensor comprises a plurality of strain gages coupled to the antenna.

8. The radar apparatus of claim 1, wherein the sensor comprises at least one photo detector array coupled to the antenna.

9. The radar apparatus of claim 1, wherein the sensor comprises at least one quadrant detector coupled to the antenna.

10. The radar apparatus of claim 1, wherein the sensor comprises a plurality of accelerometers coupled to the antenna.

11. The radar apparatus of claim 1, further comprising at least one actuator coupled to the antenna structure and responsive to the sensor to mitigate at least one sensed distortion.

12. The radar apparatus of claim 1, wherein the radar antenna is substantially planar, and the sensor detects radar antenna variation therefrom.

5. The radar apparatus of claim 5, further comprising at least one processor coupled to the at least one sensor.

13. A method for use with a radar antenna array, comprising:

detecting a relative distortion of at least one portion of the radar antenna array relative to at least one other portion of the radar antenna; and

,

providing an output dependently upon the detecting.

14. The method of claim 13, further comprising biasing the radar antenna responsively to the output.

15. The method of claim 13, further comprising providing an indication of confidence responsively to the output.

16. The method of claim 13, wherein the output is indicative of the amount of detected distortion.

17. The method of claim 13, wherein the detecting comprises:

determining distances to a plurality of points on the radar antenna; and

,

comparing the distances to known distances.

18. An alignment sensing system for a radar antenna array comprising:

a sensor arrangement operatively coupled to the radar array, the sensor arrangement sensing deviations in positions of one or more of the portions of array relative to a set of predetermined positions associated with said one or more portions and generating signals indicative of said deviations; and

a processor responsive to said signals output from said sensor arrangement for adjusting radar parameters to compensate for said sensed deviations in position of said array.

19. The system of claim 18, wherein said adjusted radar parameters include one or more of elevation, azimuth, range and velocity.

20. The system of claim 18, wherein said sensor arrangement comprises an interferometric sensor system.

21. The system of claim 18, wherein the radar array comprises a foldable antenna array.