Photonic Quantizer for Use in Photonic Analog to Digital Converters (pADCs)

Digital Signal Processing (DSP) technology has transformed modern communications. Digitizing wideband analog data is the key part in implanting DSP systems in most of applications which makes high-speed analog-to-digital converters attractive. We propose a high-speed integrated optical ADC based on Partow’s LN thin film on Silicon. In proposed photonic integrated ADC circuit, analog signal will be converted to digital signal using electro-optical phase shifting and multimode interference couplers. A complete study and characterization of phase controlling (sampling) and efficient multimode interfering (quantizing) using lithium niobite thin films in Phase I will enable us to design and fabricate a compact and integrated prototype of a photonic ADC, ready to be incorporated into test beds for high-speed ADC applications in phase II. Our proposed electrooptical approach in thin film lithium niobite platform can achieve higher speed and highly linear conversions in comparison of SOI platform, while it is comparable in case of compactness and low power consumption. The proposed ADC circuit is all optical, both sampling and quantization is done optically, and higher sampling rates than 10GHz can be easily achieved.