Injection-locked optoelectronic oscillator based on frequency conversion filtering

In this paper, an injection-locked optoelectronic oscillator (OEO) based on frequency conversion filtering process is proposed and experimentally demonstrated. The kernel of the proposed scheme is that injection locking technique is employed to obtain a high side-mode suppression ratio, while the delay-matched frequency conversion filtering process is used to eliminate the phase noise influence of the local oscillation (LO) signal. In the proof-of-concept experiment, a single-mode oscillation at 10 GHz is realized, where the frequency of the LO signal was set to be 10.07 GHz and an intermediate frequency bandpass filter with a center frequency of 70 MHz and a 3-dB bandwidth of 50 kHz is employed. The side-mode suppression ratio and the phase noise are measured to be 76 dB and -123.5dBc/Hz@10kHz, respectively.