Self-phase modulation in high-resolution DAS: impact of high-peak-power Gaussian pulses
Year: 2026
Type: article
Abstract: Modulation instability (MI) is a well-known limit for distributed fiber sensors. However, self-phase modulation (SPM) is rarely addressed as a standalone constraint in distributed acoustic sensing (DAS). This study demonstrates, through modeling and experiments, that SPM-induced spectral broadening causes significant backscattered signal losses and increased phase noise. These effects are particularly critical when using high-power, short Gaussian pulses commonly used to extend the sensing range. We highlight the predominant role of the detection bandwidth in these excess losses, proving that SPM is a limiting factor independent of MI for high-resolution nonlinear ϕ -OTDR measurements.
Source: Optics Express
DOI: 10.1364/oe.606361
Institution: Thales (France)
Language: English
Topic: Advanced Fiber Optic Sensors
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
OpenAlex ID: W7201872029