System and method for photonically assisted analog to digital signal conversion

A photonically assisted analog to digital conversion (ADC) system is presented. The system comprises: an optical sampling signal generator configured and operable for generating an optical sampling signal comprising a predetermined sampling pulse sequence in the form of a time separated pulse train of spectral components dispersed in a periodic fashion, where each pulse is distinguishable by a central wavelength thereof different from its neighboring pulses. The generation of the pulse sampling sequence is achieved by combining broadband dispersion and compensation with a periodic dispersion compensator having a free spectral range smaller than the broad bandwidth of the ultrashort pulse. The second innovative element is the introduction of coherent detection with oversampling of the interference terms of the phase modulated pulse sampling sequence and a reference pulse. The over-sampling provides additional measurements of the beat term and by way of error minimization a more reliable phase estimation is provided, translated into a more accurate conversion to digital representation. The system further comprises an electro-optical modulator for interacting an input electric analog signal and an optical sampling signal and generating a modulated optical signal indicative of said input signal; and a detection system configured and operable for receiving said modulated optical signal and generating an output digital signal corresponding to said input electric analog signal.