A Tunable Narrowband Microwave Photonic Bandpass Filter with an Ultra-High-Q Silicon Microring Resonator

We experimentally demonstrate a tunable sub-gigahertz bandwidth microwave photonic bandpass filter based on a silicon microring resonator. A 170 MHz full width at half maximum bandwidth is achieved owing to utilize an ultra-high-Q as 1.14⨯10 6 of the microring resonator. The corresponding rejection ratio is 26.5 dB. The central frequency of the bandpass filter could be tuned from 2.0 GHz to 18.4 GHz.