Methods of signal averaging for a multimode fiber interferometer: an experimental study

Three methods of multimode fiber interferometer signal averaging are investigated theoretically and experimentally: the ensemble averaging, the averaging over a long realization, and the averaging over transverse coordinates of an output speckle pattern. The analysis is performed for two wavelengths and two launch conditions of the graded-index multimode fiber: few mode and multimode. Applicability of methods for practical applications is discussed.