NSF Award
9861038
9861038<br/> This Small Business Innovation Research Phase I project will develop a wide-bandwidth digitizer with adequate memory storage needed for recording single-shot laser pulse events for studying plasma confinement. The laser pulses used in such studies have bandwidths greater than 10 GHz. Commercially available digitizers either have inadequate bandwidth, or are prohibitively expensive. A digitizer with greater than 10 GHz bandwidth, real-time memory acquisition, and a sampling rate of 16 GigaSamples/s (GSa/s) has been demonstrated. The goal of this research is to achieve 0.5 picosecond aperture uncertainty which requires extremely linear digitizing comparators. Negative feedback has been used to obtain a certain degree of linearity, but not enough to obtain the required performance (an aperture uncertainty of 0.5 ps is equivalent to 6 effective bits at 10 GHz and 8 effective bits at 2.5 GHz). A superconductive logic for correcting any remaining nonlinear effects in real time has been developed. In Phase I, a goal is to demonstrate this method at 20 GSa/s. The feasibility for providing 25 ns of on-chip 20 GHz memory and self-triggering capability will also be demonstrated.<br/> If successful, the project will enable better measurements of sub-nanosecond events for high-end electronics, communications networks, and high-speed lasers. Other government applications include digital radar, electronic warfare, and secure communications. The prime commercial application will be a general-purpose transient digitizer. The successful fielding of a transient digitizer from this project could compensate for the recent withdrawal of a U.S. product, which has resulted in the ascendancy of a foreign digitizer product to the position of highest performance.
