Highly Spectrally Pure 90-GHz Signal Synthesis Using a Coupled Optoelectronic Oscillator

Abstract

A 90-GHz frequency reference is synthesized through harmonic generation from a 30-GHz coupled optoelectronic oscillator. The 30-GHz signal and its third harmonic feature an average power level of -5.6 and -15.8 dBm, respectively, at the photodiode output. Phase noise measurements at 30 and 90 GHz have been performed and phase noise levels as low as -114.4 dBc/Hz at 1-kHz offset for the fundamental and -104 dBc/Hz at 1-kHz offset frequency for the 90-GHz signal have been obtained.