We report on the use of an adaptive signal processing technique called Adaptive Line Enhancement with Coherent Accumulation (ALECA) for improving the time domain signals captured from a Fiber Bragg grating-based acoustic emission sensor. The acoustic emission sensor is able to detect signals from a few kHz to 1 MHz with a sensitivity of 1 micro strain. We demonstrate the usefulness of ALECA for extracting the time domain signals from standard ball drop tests. © 2012 IEEE.