Spatial Resolution Enhancement in Preactivated BOTDA Schemes by Numerical Processing

A novel processing algorithm is demonstrated for time-domain high-resolution Brillouin schemes based on acoustic field preactivation. An iterative method is employed to correct the measured data from spurious effects associated with acoustic wave transients. Based on a model of the stimulated Brillouin scattering in the frequency domain, the spatial resolution degrading features are computed and subtracted from the acquired data. Experimental tests with 20-cm spatial resolution and dark-pulse pumping are reported.