A generalization of the main linear and nonlinear correlation methods,
the dual nonlinear correlation (DNC), is introduced. Various filters
(CMF, POF, IF, FPF, PPC, OF) appear to be special cases of the DNC. Th
e convolution formula describing the peak shape and the intermodulatio
n effects for the noise-free multi-object scenes is discussed. Optimiz
ation of the DNC according to the peak-to-correlation energy criterion
is performed. Superior performance of the PPC is presented. The influ
ence of noise on the intermodulation effects is studied. Hybrid, optoe
lectronic realization of the DNC based on joint transform correlator a
rchitecture with nonlinear preprocessing which allows the introduction
of various correlation methods without any filters is proposed.