Zhonghong Lin

We propose what we believe to be a novel frequency-modulated continuous-wave distributed acoustic sensing (FMCW-DAS) system utilizing the sub-chirp-multiplexed spectral matching (SCM-SM) method. Multiplexing N sub-chirp probe signals enhances the theoretical maximum measurable frequency N-fold beyond the conventional single-shot limit.

Abstract Distributed fiber-optic sensing has become an indispensable tool for large-scale structural and environmental monitoring, where spectral interrogation of backscattering light enables high-precision quantitative measurement of external perturbations. Conventional spectral analysis methods, typically based on frequency-domain serial interrogation or time-to-frequency mapping, face inherent trade-offs between measurement speed, dynamic strain measurement range, and system complexity.