All optical instantaneous frequency measurement incorporating optical Hilbert transformer

A novel method to incorporate an optical Hilbert transformer with an all-optical photonic instantaneous frequency measurement system is proposed and demonstrated. Two orthogonal measurements of an RF signal are obtained which enables determination of both signal frequency and power. This system produces DC outputs that simplify the receiver and reduce cost. The system is demonstrated between DC and 20 GHz but can be scaled to 40 GHz and beyond.