Intermodulation Distortion of a Comb-Based RF Photonic Filter Using Balanced Detection

We investigate intermodulation distortion of a tunable radio frequency photonic filter utilizing an optical frequency comb, an interferometric configuration, and a balanced detection. When the filter passband is tuned from 2 to 7 GHz, this scheme has the third-order spurious free dynamic range of <;108.2 dB·Hz2/3. In addition, we investigate the effect of Mach-Zehnder modulator (MZM) configuration on second-order intermodulation. A high extinction ratio MZM results in 43-dB lower power in the second-order intermodulation tones compared with that obtained with a conventional MZM.