What are possible causes of a reflective OTDR trace signature?

A reflective OTDR (Optical Time Domain Reflectometer) trace signature can be influenced by various factors related to the physical and optical characteristics of the fiber optic cables.

Fusion splices can create reflective signatures due to the variations in refractive index at the junction where two fibers are welded together. If the splice is not executed perfectly or if there is a mismatch in the core diameters or refractive indexes, this can lead to significant reflections. Microbends—small, localized bends in the fiber—can also reflect light back towards the source, impacting the trace observed on the OTDR.

Mechanical splices, where two fibers are aligned and held together using an adhesive or fixture, can introduce reflections because of imperfections at the splice point, similar to fusion splices. Additionally, abrupt changes in the fiber’s characteristics, such as those found at fiber ends, can lead to notable reflective appearances in the OTDR trace.

Furthermore, optical fused biconical taper splitters are devices that combine or split optical signals and have specific characteristics that can also contribute to reflections, depending on the design and how they are integrated into the optical network.

Given that all the mentioned scenarios can indeed cause a reflective signature in the OTDR trace, the correct answer highlights that