A photonic technique for microwave frequency measurement employing tunable dispersive medium

We propose a novel photonic technique for microwave frequency measurement by employing an optical group delay line. The 7-bit optical delay line composed of several magneto-optical switches and 1.6km single-mode fiber (SMF) is designed as a tunable dispersive medium (TDM) in the measurement system. In our scheme, the measurable frequency range of 1-20GHz with a measurement error less than ± 40MHz is demonstrated experimentally. Also, we have studied the dynamic range of the measurement system.