Cross-correlation of system outputs-ambiguity function

Outputs of disjoint linear systems may be correlated for a nonstationary input process. For a nonstationary white input, the output cross-correlation function is simply characterized in terms of the generalized ambiguity function. An example is given for passive radiowave measurements with multiple individual sensors, in which case the ambiguity function is the spatial inverse Fourier transform of the aperture field cross-correlation.<
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