Optoelectronic ADC integrated circuit technology

"Direct detection radar requires both AD and DA conversion located essentially at the antenna or at the LNA output. The advantages are dramatic improvements in EMI interference and dynamic range and a reduction in power and complexity. For example with RFat 2 - 10 GHz, the down conversion process could be eliminated by direct digital conversion if sampling at 20GS/s were possible. In addition, an AD converter with digital optical output is ideal for coupling to fiber for remote connection to the processor.Similarly, D/A conversion with fiber input can carry digital routing information for an optical switch matrix to implement TTD as well as to carry RF optical energy. State-of-the-art electronic research-based converters provide GS/s but only with 4 - 6bits of resolution whereas 10-12 bits are needed for digital radar. We propose an optoelectronic thyristor comparator combined with HFET differential amplifiers to form a compact AD quantizer. The thyristor comparator provides digital optical outputs. Thethyristor also provides the unique opportunity to sample at very high speeds without clock feedthrough. The ADC has been demonstrated with discrete thyristors and COTs amplifiers. In this SBIR we will develop the integrated circuit technology todemonstrate high speed ADC operation. The thyristor/FET will enable practical very high speed O/E ADC suitable for the numerous sensing systems. The optical output and CCD compatibility can tra