Experimental Demonstration of a Real-time Photonic Analog-to-Digital Conversion Scheme Operating at 40 Gigasamples/s

Paper in proceeding, 2005

Abstract We have experimentally demonstrated a novel interferometric scheme for photonic analog-to-digital conversion (ADC), at a real-time sample rate of 40 gigasamples/s. In the experiment we used a 1.25 GHz sinusoidal tone (electrical) as input signal and reached a resolution of 21 digital levels with an effective number of bits (ENOB) of 3.6. This scheme benefits from using only one standard phase modulator, giving immediate access to the bandwidth of state-of-the art fiber-optical telecom modulators. It further benefits from the ultra-low temporal jitter attainable using a mode-locked laser as sampling-pulse source, and the low required phase swing greatly enhances the inherent bandwidth as compared to many other interferometric schemes.