Improved Dynamic Range Microwave Photonic Instantaneous Frequency Measurement Based on Four-Wave Mixing

An improved dynamic range instantaneous frequency measurement system based on four-wave mixing effect in a highly nonlinear fiber was practically demonstrated. A closed-form model was developed to predict the behavior of the system. The model predicted that the system output would have a low frequency voltage which was a function of RF input frequency. The system performance was also practically demonstrated. The system characterization showed a 0.04-40-GHz frequency measurement range with 51-dB dynamic range for 100-MHz measurement error at the end of the band. A maximum relative measurement error of 0.35% was achieved over the entire frequency range. This dynamic range was achieved by employing the lock-in amplification technique.