Two-level injection in fiber-delay line based oscillator

Abstract

Two-level injection-locked opto-electronic oscillator is proposed for low phase noise. Dielectric resonator oscillator (DRO) is used as the first injection source, injection locking a long-fiber loop based opto-electronic oscillator, then its output is injection locking another long-fiber opto-electronic oscillator for getting a lower-phase noise output carrier. After the first injection, the single side band (SSB) phase noise at 10kHz offset frequency decreases from −123dBc/Hz to −135dBc/Hz, then through the second injection the SSB phase noise drops down to −146dBc/Hz.