Patent ID: 8963751
Filing Date: 2015-02-24
Classification: G02F,H03M

Abstract:
1. A photonically assisted analog to digital conversion (ADC) system comprising: 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, where each pulse is distinguishable by a central wavelength thereof different from its neighboring pulses; an electro-optical modulator for interacting an input electric analog signal and the 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; the ADC system being configured and operable for carrying out at least one of the following: (a) interfering said modulated optical signal with a reference signal corresponding to the optical sampling signal so as to provide oversampling of interference terms of the signals, thereby improving phase estimation corresponding to the input electric analog signal; and (b) providing said predetermined sampling pulse sequence in the form of the time separated pulse train of spectral components dispersed in a periodic fashion, the optical sampling signal generator having one of the following configurations: (i) comprises a cascade arrangement of a continuous chromatic dispersive element and a wavelength division multiplex (WDM) dispersion compensator having a free spectral range (FSR) equal to a channel separation, thereby producing a staircase group delay transfer function, which separates an incident transform-limited ultrashort pulse into a burst of output pulses, each being transform-limited by a stair bandwidth and offset from its neighboring pulses in time by a staircase step height; (ii) comprises an optical dispersion compensator, and a wideband chromatic dispersive unit, to thereby provide spectrally and temporally separate pulse train presenting a combined staircase group delay.