Phase noise of a high performance OEO and an ultra low noise floor cross-correlation microwave photonic homodyne system

This paper describes two recent types of opto-electronic oscillators. The first is a long fiber opto-electronic oscillator, utilizing a high power laser with long delay, and consisting of low noise components. This oscillator generates a stable 10 GHz signal with phase noise of -163 dBc/Hz at 6 kHz offset from the carrier. The second is a low noise 10 GHz compact opto-electronic oscillator. This latter oscillator consists of coupled optical and microwave loops utilizing a short fiber. We also report on an automatic ultra-low noise floor measurement system, designed and built to measure the phase noise of the above (and other) oscillators. This delay line cross-correlation measurement system utilizes microwave-photonic links, eliminating the need for a second oscillator. This system provides quick and reliable measurement of the oscillator under test.