Microwave frequency measurement with improved measurement range and resolution

An approach is proposed and demonstrated to improve the measurement range and resolution of a microwave frequency measurement system. Two optical wavelengths are modulated by a microwave signal in a Mach-Zehnder modulator (MZM). The optical output from the MZM is sent to a dispersive element to introduce different chromatic dispersions, leading to different microwave power penalties. A fixed relationship between the microwave power ratio and the microwave frequency is established. The microwave frequency is estimated by measuring the microwave powers. A new measurement range is defined with an improved measurement range and resolution. Analysis is performed and confirmed by an experiment.