Comparison of different statistical methods for specklegram-based fiber optic vibration sensor

Vibrations and their parameters can be measured through monitoring the speckle pattern of multimode optical fiber. In this paper a modified approach to realization of a specklegram based vibration sensor system is discussed. Replacing the (standard) camera detector with an array of several detector diodes improves the size and frequency range of the system. Different statistical methods for processing the signals from the diode array are presented, compared experimentally and discussed. The principal advantages of the specklegram vibration detection approach, low cost and distributed detection possibility, have been retained.