Tunable multi-frequency optoelectronic oscillator based on a microwave photonic filter and an electrical filter

We propose and experimentally demonstrate a multi-frequency optoelectronic oscillator (OEO) based on the phase-modulation to intensity-modulation conversion. A microwave photonic filter incorporating an optical fiber Bragg grating Fabry–Perot filter and an electrical yttrium iron garnet (YIG) filter in two branches are used to select the oscillation modes of the OEO. By adjusting the wavelength of laser source or the central frequency of YIG filter, two frequencies can be tuned independently within a wide range. The single sideband phase noises of the generated frequencies are measured experimentally. Moreover, the OEO shows potential ability to achieve more frequencies oscillation by multiplexing more optical and electrical filters.