EXPERIMENTAL AND SIMULATION STUDIES ON THE PERFORMANCE OF BINARY AND GRAY-VALUED JOINT TRANSFORM CORRELATORS UNDER POOR ILLUMINATION CONDITIONS AND NONOVERLAPPING BACKGROUND-NOISE

The correlation performance of four different types of joint transform correlators (JTCs) is investigated in a noncooperative situation when the target image is cluttered with scene noise and present under poor illumination condition, Computer simulation and experimental results are provided. Although the binary JTCs based on spatial-frequency-depe ndent threshold (SFDT), sliding-window local-median threshold (SWLMT) offer good correlation performance in poor target image illumination c onditions their performance is affected in the presence of background noise in the target image. The JTC based on modified-fringe-adjusted f ilter (MFAF) performs better in such a combined situation. (C) 1997 So ciety of Photo-Optical instrumentation Engineers.