In-flight line-of-sight sensor boresighting using GPS receiver data

A technique is presented to boresight a two-axis line-of-sensor, in-flight, using outputs from an inertially aided GPS receiver. This technique implements scalar Kalman filters in the sensor's line-of-sight frame to estimate errors between a computed sensor line-of-sight and readouts available from the sensor while tracking a surveyed ground reference point. Compensations for INU attitude and position errors are applied in the computed line-of-sight prior to entering these scalar filters. The a priori knowledge of the INU attitude and position errors, available from the GPS receiver's outputs, is used in applying the compensations. Monte Carlo simulation results are presented showing the boresight accuracies achieved using this technique based on a single encounter for several aircrafts, and improvements available from multiple encounters with the ground reference point for a single aircraft.<<ETX>>