Non-local effects in a Brillouin optical frequency-domain analysis system

Systematic errors due to the energy transfer between the pump and probe waves in distributed Brillouin sensors have been widely studied in conventional schemes based on a pulsed pump wave. These studies led to the formulation of guidelines and/or novel schemes, allowing strict control of these errors. In this paper, we analyze numerically and experimentally the influence of non-local effects in Brillouin optical frequency-domain analysis sensors. Due to the continuous interaction of the optical waves along the fiber, we show that non-local effects are influenced by the power of both pump and probe waves. Our analysis, performed for a single-sideband and a double-sideband BOFDA scheme, leads to the formulation of simple guidelines to make the impact of non-local effects negligible.