Coherent detection of very narrow linewidth millimetre-wave and microwave signals

摘要

A coherent-detection technique for very narrow linewidth millimetre-wave and microwave signals is described. Wide laser linewidth is eliminated at the receiver by nonlinear operation. An experiment demonstrating such a technique with laser intermediate-frequency linewidth of 200 MHz is reported, where the resulting electrical linewidth is limited only by the resolution bandwidth of the spectrum analyser.