Multi-format microwave signal generation based on an optoelectronic oscillator

A novel approach to generating multi-format microwave signals directly from an optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. Through applying different low-frequency electrical waveforms to the bias port of the electro-optic Mach-Zehnder modulator, the net gain in the OEO cavity is dynamically controlled to make the OEO work at different status. Hence, different microwave signals can be generated in the oscillation process. In the proof-of-concept experiment, a single-tone microwave signal at 4.005 GHz is generated by using a direct-current driving voltage. Microwave pulse trains centered at 4 GHz and with repetition rates of 390 kHz and 3.9MHz are generated under fundamental and 10th-order harmonic mode locking, respectively, by using sinusoidal driving voltages. Besides, rectangular microwave waveforms centered at 4 GHz and with duty cycles of 25%, 50%, and 75% are generated under gain switching status by using rectangular driving voltages. The proposed method is also able to generate other types of microwave signals in a broad frequency range, which can find applications in a multi-functional microwave photonic system. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

A novel approach for generating multi-format microwave signals directly from an optoelectronic oscillator (OEO) is proposed and experimentally demonstrated in this study. By dynamically controlling the net gain in the OEO cavity, different microwave signals can be generated, including single-tone signals, pulse trains, and rectangular waveforms with varying duty cycles. The proposed method shows potential for generating various types of microwave signals in a broad frequency range, making it suitable for applications in multi-functional microwave photonic systems.