Abstract: A seeker head comprises a seeker for scanning field of view and a gyro assembly sensing attitude variations. Signal processing means process information from two consecutive scans of the seeker. The signals from the gyro assembly are applied to a coordinate transformer circuit, which transforms the picture information from consecutive scans into a common intertial coordinate system. A target is selected by target selection logic. The coordinates of a selected target are read into a deviation memory. The signal processing means provide the inertial sight line rate of the sight line to a selected target. After each scanning and signal processing cycle the location is computed at which the target is to be expected according to the sight line rate measured during the preceding cycle. This permits comparison of target signals in consecutive scans even with moving targets, recovery of temporarily lost targets and discrimination between actual targets, such as an aircraft, and mocktargets, such as flares.

Abstract: In a seeker head a field of view is scanned cyclically for providing picture informations referenced to a seeker-fixed coordinate system. The seeker carries a gyro assembly, which provides attitude variation signals as a function of attitude variations of the seeker relative to inertial space. The attitude variation signals are applied to a coordinate transformer which transforms all picture informations with their addresses into an inertial coordinate system which coincided with the seeker-fixed coordinate system after the completion of the preceding scan. Thereby during each scan all picture informations are transformed into one single inertial coordinate system. After the completion of the scan, the picture informations are again transformed into an inertial coordinate system, which coincided with the seeker-fixed coordinate system at the end of said scan, and are stored in a memory. This is the same coordinate system into which the picture informations will be transformed during the next-following scan.