The use of nonlinear techniques in the Fourier plane of pattern recognition correlators can improve the correlators’ performance in terms of discrimination against objects similar to the target object, correlation peak sharpness, and correlation noise robustness. Additionally, filter designs have been proposed which provide the linear correlator with invariance properties with respect to input signal distortions and rotations. In this paper, we propose simple modifications to presently known distortion invariant correlator filters which enable these filter designs to be used in a nonlinear correlator architecture. These Fourier plane nonlinear filters can be implemented electronically, or may be implemented optically using a nonlinear joint transform correlator. Extensive simulation results are presented which illustrate the performance enhancements that are gained by the unification of nonlinear techniques with these filter designs.

Date Published: 9 August 1996
PDF: 30 pages
Proc. SPIE 10287, Optoelectronic Devices and Systems for Processing: A Critical Review, 1028703 (9 August 1996); doi: 10.1117/12.259694

Published in SPIE Proceedings Vol. 10287:
Optoelectronic Devices and Systems for Processing: A Critical Review
Bahram Javidi; Kristina M. Johnson, Editor(s)