Wideband tunable optoelectronic oscillator based on a single-bandpass microwave photonic filter and a recirculating delay line

A wideband tunable optoelectronic oscillator (OEO) based on a tunable single-bandpass microwave photonic filter (MPF) and a recirculating delay line is proposed and experimentally demonstrated. The MPF is formed by cascading a finite impulse response filter and an infinite impulse response filter, which can enhance the quality factor of the MPF and suppress the side modes of the OEO. The frequency response of the tunable MPF is theoretically analyzed. By placing the MPF into the OEO, tunable microwave signals from 10.3 GHz to 26.7 GHz and a 100 MHz step tunability are experimentally demonstrated. The phase noise is −113 dBc/Hz@10 kHz. The results agree well with the theory.