Coherent detection SNR of an array of detectors.

General equations are derived for the SNR of a coherent (heterodyne) receiver constructed from an array of detectors and i.f. amplifiers. The equations are in terms of the distribution functions of the signal and local oscillator fields, the distributions of gain and phase shift among the i.f. amplifiers, and the sizes and shapes of the individual detectors. Such a receiver can efficiently detect any signal distribution function, no matter how badly aberrated, if the individual detectors are small enough, and the i.f. amplifier gains and phase shifts are set correctly.