30 Gsample/s 4-bit time-stretch analog-to-digital converter

Summary form only given.Photonic time stretch preprocessing (TSP) has been proposed as a means to enhance the performance of electronic ADCs. This concept is based on the premise that if the analog signal can be stretched in time free of distortion, then the effective sampling rate and the input bandwidth of the ADC is increased. The technique is best suited for time-limited analog signals, such as those encountered in pulsed radars. In this paper we demonstrate complete time-stretch ADC with 30 Gsample/s sampling rate, and 4 effective number of bits resolution realized over a 4 GHz bandwidth. The system consists of a photonic TSP and a commercially available electronic digitizer with 8 Gsample/s sampling rate and 1.5 GHz bandwidth.