Optoelectronic oscillators (OEOs) can generate high-purity RF signals with very low phase noise. The application covers a wide area of photonic and RF systems such as microwave frequency standards, radars, RF photonics and optical signal processing. Conventional OEOs have two potential drawbacks: RF amplifiers with high gain (up to ~ 60 dB) are needed to compensate the RF link loss of the feedback loop; and high frequency operation is challenging. To overcome the drawbacks and further enhance the performance of OEO, we propose a novel optical injection-locked optoelectronic oscillator (OIL-OEO). Optical injection locked semiconductor lasers exhibit two desirable features: (1) greatly enhanced resonant frequency. The new resonance frequency is proportional to the injection ratio, and can potentially reach above 100 GHz; (2) Enhanced RF modulation efficiency at the resonant frequency. Efficient modulation can be achieved at the enhanced resonance frequency of injection-locked lasers. This could alleviate the need for high-frequency RF amplifiers and optical modulators in the conventional OEO loop. In this program, we will demonstrate ultrahigh frequency (60-90 GHz) OEO using this novel optical modulation scheme.
Project end date: 08/15/07