On the Signal-to-Noise Ratio for Optical Heterodyne Detection

Abstract

The conventional result for the signal-to-noise ratio in an optical heterodyne detector is shown to apply to the mixing of a stable local oscillator with any radiation field which gives rise to a stationary narrow-band i.f. signal. The result is explicitly demonstrated for radiation scattered from a diffuse target, which may be represented as a narrow-band Gaussian random process.