Tunable Microwave Pulse Generation Based on a Time-Domain Mode Locked Optoelectronic Oscillator

A tunable microwave pulse generator is proposed and demonstrated. In this study, a time-domain mode locked optoelectronic oscillator (OEO) is realized by utilizing a dual-parallel Mach-Zehnder modulator (DPMZM). One branch of the DPMZM is modulated by the feedback signal and another branch is modulated by an inject signal. When the frequency of the injected signal is equal to an integer multiple of the oscillation mode space, the time-domain mode locking is achieved in the OEO loop and the microwave pulse trains are generated. In the experiment, the phase noise of the generated signal is −93 dBc/Hz, the frequency range of the generated signal is 6–12 GHz, the time duration of the generated microwave pulse can be adjusted from 620 ns to 2970 ns, and the repetition rate of the generated microwave pulse can be set to 185.1 kHz, 370.2 kHz and 555.3 kHz.