Phase measurement system operating at constant frequency

In this work, we propose an electronic structure, to transform the phase of two high-frequency signals to the low frequency domain, using mixers and associated filters. To keep a constant resolution phase, for signals with variable frequency, we have developed a digital technique to construct a reference signal required to active the phase measurement system operating at constant frequency. Design blocks and simulation results will be presented to validate the measurement and error of phase shift, followed by a discussion on the choice of parameters.