Monolithic GaAs digitizer for space-based laser pulse spreading effect

Abstract

A 6-bit 1-GHz digitizer was designed to analyze the 1-ns pulse spreading effects in a space based altimeter. The digitizer consisted of four 4-bit flash A/D converters and a 6-bit encoder. Also, the converter utilized four 4-bit converters and a 4-to-6 bit encoder to achieve 6 bit resolution at the 1 GHz sample rate. The design was unique because it utilized only the inverters and NOR gates for the converters and encoder, hence it could be fabricated using the existing state-of-the-art GaAs processing techniques. This GHz digitizer has many commercial applications. It could be applicable to: (1) digital microwave transmission system for the telecommunication industries, (2) pulse monitoring in high kinetic chemical reactions, (3) transient signals in the medical field, and (4) microwave signals in astronomy.