Probability density of the phase error of a digital interferometer with overlapped FFT processing

Advanced interferometric direction finding systems often use the Fast Fourier Transform (FFT) for computing the relative phase shifts of the signals corresponding to pairs of antenna elements. An exact formula was recently derived for the probability density of the phase error for the case when the overlap ratio γ of the FFT input data blocks is 0. This paper extends the previous work to derive an exact formula for the probability density for the general case of an arbitrary overlap ratio γ ∈ [0, 1).