What Is a Gap Loss?

Gap loss is a phenomenon in fiber optics where the signal is disrupted by a gap between cables that should be aligned with each other. It can be the result of a problem with the way technicians laid the cables, and in some cases, it may be deliberately induced with the assistance of an attenuator device. Unplanned gap loss can be a problem in fiber optic systems that may interfere with the smooth transmission of data, and thus technicians need to be able to identify and fix it quickly.

This type of cabling relies on the use of a visible signal to transmit information. At a point where two wires join, they need to be carefully aligned with each other to allow the signal to move freely between the cables. If they are not aligned correctly, gap loss can occur. The light spreads as it exits one cable, scattering to hit the cladding around the neighboring cable rather than targeting the fiber optic wiring inside. As a result, some of the signal is lost.

When it is unintentional, it can be the result of failing to position cables properly, as in the case of problems like angular misalignment loss, where the cables do not align at the correct angle. When an attenuator is installed between two cables, it creates gap loss. This may be used to control power differentials, where a high powered signal could interfere with the line. It can also be used to simulate gap loss in the wild for the benefit of technicians performing testing and install activities.

Simulation of gap loss in the lab can provide important information about cable performance under adverse conditions. It can also offer insight into what data loss looks like when a gap is the issue. This can be helpful for diagnostic procedures to determine the cause of a faulty signal. It can also be used in research and development to create cabling that will be less susceptible to gap loss, with a wider range of tolerances to prevent problems in field applications.

When simulating gap loss in the lab, technicians can carefully calibrate their attenuators to control the conditions. They can explore what happens with different settings as well as adjustments to the position of the line to collect as much data as possible about the data loss. Measurements can also be taken to see how the light behaves as it tries to cross the gap.