A Pseudo-Superheterodyne Receiver for Measuring Phase and Amplitude

A simple high-sensitivity receiver for simultaneously measuring the amplitude and phase of signals at radio and microwave frequencies is described. The receiver is built, for the most part, with standard (microwave) components and employs a modulation technique. The receiver sensitivity, depending on the information bandwidth, is of the order of -100 dBm. Information bandwidths ranging from a few Hz to several MHz are easily achieved.