Optical Sampler for Broad-Spectrum Sensing

David Perlmutter | 19-FS-018

Overview

We investigated the feasibility of using non-uniform optical sampling to measure wide-bandwidth radio frequency (RF) signals more efficiently. Our work combined two areas of signal measurement research to increase accuracy and reduce cost over current state-of-the-art sampling devices: 1) optical sampling, which uses optics to alleviate the bandwidth limitations of traditional electronic sampling, and 2) compressed sensing, which seeks to measure signals with fewer samples than typically necessary. However, several different compressed sensing architectures and algorithms offer varying levels of performance, robustness, and complexity. We compared trade-offs between several of these methods in a simulation of a remote sensing application. We found that, while feasible, compressed sensing is inherently less sensitive than fully sampled systems; therefore, it must be paired with a very low-noise optical system. We also built an experimental prototype of the system and took initial measurements.

Impact on Mission

Our work leveraged and advanced Lawrence Livermore National Laboratory's core competencies in laser and optical science and technology. Our results broaden the capability and applications space of photonic analog-to-digital converters at Livermore's National Ignition Facility, which ultimately supports the Laboratory's stockpile stewardship mission.