Minimax Noncoherent Detection of BFSK Signals in Nonwhite Gaussian Noise

We derive an optimum receiver for noncoherent detection of binary frequency shift keyed (BFSK) signals in nonwhite Gaussian noise. It will be shown that the achieved symbol error rates are smaller when operating on a nonwhite Gaussian noise channel than on a white Gaussian noise channel. The well-known BFSK receiver designed for white noise proves to be a minimax receiver when used in nonwhite noise. We show that the symbol error probability of the minimax receiver does not depend on the noise characteristics.