Limits in Timing Jitters of Forced Microwave Oscillator Using Optical Self-ILPLL

Abstract

A novel optical feedback technique using self-injection locked and phase locked loop (SILPLL) is employed for phase noise reduction of free-running microwave oscillators. Phase noise reduction of 27 dB at 10-kHz offset has been demonstrated by applying this technique for a 10-GHz state of art dielectric resonator oscillator achieving -137 dBc/Hz at 10-kHz offset. A phase noise prediction of this feedback technique is also presented, which very closely corroborates with experimental results. Analysis of SILPLL using the modeling has shown that further phase noise reductions could be achieved, by reducing the flicker phase noise of the long delay lines and microwave amplifiers. Phase noise of -147 dBc/Hz at 10-kHz offset is predicted when the relative intensity noise (RIN) is reduced to the RIN of -170 dB/Hz for an optical power leading to a photocurrent of 5 mA and the b-1(flicker noise) levels of -125 dBc/Hz for RF amplifiers.