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A New Approach Defining Angular DMD Using Near Field Aperturing

Authors: S. Al-Sowayan, K. L. Lear


A new technique to quantify the differential mode delay (DMD) in multimode fiber (MMF) is been presented. The technique measures DMD based on angular launch and measurements of the difference in modal delay using variable apertures at the fiber face. The result of the angular spatial filtering revealed less excitation of higher order modes when the laser beam is filtered at higher angles. This result would indicate that DMD profiles would experience a data pattern dependency.

Keywords: fiber measurements, Fiber optic communications

Digital Object Identifier (DOI):

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