A New Approach Defining Angular DMD Using Near Field Aperturing

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.

• S. Al-Sowayan
• K. L. Lear

• Fiber measurements
• Fiber optic communications

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