| US 7,548,189 B2 | ||
| Using radar targets of opportunity to build a monopulse calibration table | ||
| Yair Alon, Thousand Oaks, Calif. (US); and Mark Jacobs, Simi Valley, Calif. (US) | ||
| Assigned to Northrop Grumman Corporation, Los Angeles, Calif. (US) | ||
| Filed on Aug. 21, 2006, as Appl. No. 11/507,332. | ||
| Prior Publication US 2008/0042896 A1, Feb. 21, 2008 | ||
| Int. Cl. G01S 7/40 (2006.01); G01S 13/44 (2006.01) | ||
| U.S. Cl. 342—174 [342/149; 342/152] | 48 Claims |
| 1. A method of building a monopulse calibration table from a live target of opportunity using signals received from the target
at sum and difference antenna channels of a rotating radar antenna that receives signals within an angular-shaped beam, the
center of which is the antenna's bore-sight, the angle formed between a reference direction and the bore-sight being an azimuth
angle, the method comprising the steps of:
a) at each of a plurality of N different azimuth angles, calculating a normalized received signal from a target of opportunity
using a signal received from the target at a sum channel and using a signal received from the target at a difference channel;
b) identifying the azimuth angle of where the target of opportunity is actually located as the azimuth angle whereat the magnitude
of the normalized received signal obtained in step a) is greatest;
c) for each of the other N azimuth angles of step a), calculating the difference between each of the N azimuth angles of step
a) and the azimuth angle determined in step b) to obtain N, off-bore sight angles where each of the normalized received signals
of step a) was determined;
d) storing each of the normalized received signal obtained at step a) with a corresponding off bore sight azimuth angles determined
in step c).
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