Pattern discrimination using a bank of wavelet filters in a joint transform correlator

We introduce and demonstrate the use of wavelet-filter-based processing in a joint transform correlator for achieving high-quality target discrimination. The inherent frequency localization characteristic of these filters offers high discrimination in correlation for lookalike targets. Re- sults obtained from simulation and experimental studies validate this fact. Wavelet filters are generated and applied to the joint power spec- trum through fast digital processing and are displayed onto a spatial light modulator. The correlation results are analyzed for target discrimination. The hybrid experimental setup combines the speed of optical processing with the flexibility of digital processing to realize such a technique in real time. © 1998 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(98)04202-0)

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