40 GSPS all-optical ADC with ENOB of 6.6 using EO polymer optical deflector and spatial quantizer

40GSPS analog-to-digital converters (ADC) are required for realization of digital receivers up to 20GHz. An all optical ADC is presented using an optical deflector for spatial sampling. The optimized design of optical deflector is based on optical beam propagation and finite element modeling electromagnetic modeling. An effective number of bits (ENOB) of 6.6 ADC is achieved under a ±20V RF voltage swing and by minimalizing angular resolution with a leaky waveguide of 2cm long. Design and implementation of a polymer waveguide are presented, meeting the leaky waveguide coefficient of 0.1Np/cm and low optical attenuation with quality optical waveguide surface flatness better than 20nm. A broadband (2-40GHz) transition from coplanar waveguide (CPW) to coupled microstrip (CMS) transmission lines is presented that overcomes the RF attenuation to achieve under 0.06Np/cm variation by using a pre-emphasis filter with a flat group delay of less than 70ps.