Fast Brillouin optical time-domain analysis using frequency-agile and compressed sensing.

Abstract

A fast Brillouin optical time-domain analysis (BOTDA) sensor has been proposed and experimentally demonstrated based on the frequency-agile and compressed-sensing technique. The proposed scheme employs a data-adaptive sparse base obtained by the principle component analysis algorithm, enabling the sparse representation of Brillouin spectrum. Then, it can be reconstructed successfully with random frequency sampling and orthogonal matching-pursuit algorithms. In the experiment, the Brillouin gain spectrum (BGS) is mapped by the conventional fast BOTDA, where the frequency step and span are 4 MHz and 500 MHz, respectively. By using compressed-sensing technology, the BGS is successfully recovered with 37 random frequency samples, the number of which is only 30% of the full data. With fewer sampling frequencies, the compressed-sensing technology is able to improve the sensing performance of the conventional fast BOTDA, including a 3.3-time increase in sampling rate and 70% reduction in data storage.