Excess Loss is the amount of loss that a passive coupler exhibits, which is inherent in the act of dividing light among the output ports. It is the light that fails to be diverted from the nominal operation ports of the coupler. In the context of cables, this is the amount of energy that is lost in the signal as it is transferred from one end of the cable to the other.
Excess loss typically results from inherent losses in the coupler, such as those caused by connector imperfections, material absorption, and surface scattering. It can also result from the design of the coupler itself, such as if the output ports are not properly aligned or the device is not optimized for the particular application it is used in. In addition, excess loss can be caused by environmental factors, such as extreme temperatures or dust.
Excess loss results in a decrease in the signal strength of the transmitted signal, which can lead to degraded performance, noise, and interference. It is important for installers to ensure that the cables and connectors used for a particular application are optimized for the job and that the environment is free from extreme temperatures and dust. The amount of excess loss for a particular cable should be documented during installation and monitored regularly to ensure that the signal strength is not degrading over time.
Excess loss is an important factor to consider when designing and installing a cable system. It is important to select cables and connectors that are optimized for the particular application, as this will help to minimize excess loss and ensure reliable performance. In addition, it is important to be aware of environmental conditions and to take steps to reduce excess loss where possible.