Angle Calibration of Long Baseline Antennas

• US 20080259317A1
• Filed: 04/20/2007
• Published: 10/23/2008
• Est. Priority Date: 04/20/2007
• Status: Active Grant

• Current Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Original Assignee: Northrop Grumman Systems Corporation (Northrop Grumman Corporation)
• Inventors: Gordon, Wayne John, Lennon, David Curtis, Adams, Marc S., Schering, Roy, McMillan, Donald Richard
• Granted Patent: US 7,558,688 B2
• Time in Patent Office: Days
• US Class Current: 356/72
• CPC Class Codes: G01B 11/27 for testing the alignment of axes means for centering or aligning a light guide within a ferrule G02B6/3834

Abstract

A method for calibrating a sensor mounted on an aircraft includes the steps of: using an optical device to create reference points which define a reference line that is parallel to both horizontal and vertical planes of the sensor, and using the reference line to calibrate the sensor with respect to a reference coordinate system.

Claims

1. A method for calibrating a sensor mounted on an aircraft, the method comprising the steps of:

using an optical device to create reference points which define a reference line that is parallel to both horizontal and vertical planes of the sensor; and

using the reference line to calibrate the sensor with respect to a reference coordinate system.

2. The method of claim 1, wherein the step of using the reference line to calibrate the sensor with respect to a reference coordinate system comprises the step of:

sending an orient message to an inertial navigation unit reflecting corrections that force the inertial navigation unit to report its heading and pitch in a coordinate frame of the sensor.

3. The method of claim 1, wherein the step of using the reference line to calibrate the sensor with respect to a reference coordinate system comprises the step of:

adding corrections to heading and pitch angles reported by an inertial navigation unit.

4. The method of claim 1, wherein the step of using an optical device to create reference points which define the reference line comprises the steps of:

directing an optical beam through first and second irises connected to the sensor; and

using the optical beam to establish first and second reference points.

5. The method of claim 4, further comprising:

determining the locations of the first and second reference points.

6. The method of claim 5, wherein the locations of the first and second reference points are determined using a global positioning system.

7. The method of claim 1, wherein:

the reference coordinate system is established by an inertial navigation system.

8. The method of claim 1, wherein:

the reference line is parallel to a horizontal plane of the sensor and a vertical plane of the sensor.

9. The method of claim 1, wherein the sensor comprises:

an antenna.

10. The method of claim 9, wherein the antenna comprises:

a planar array of elements.