What are Aerial Fiber Optic Cables?
In optical signal transmission, we often have to overcome long distances, and one solution for these long paths is the installation of aerial cables.
For these applications, an aerial installation is a much faster and cheaper method. However, these cables are directly exposed to the elements, which can be quite severe in some locations.
Aerial cables are built to have a lifespan of 25 years, resisting wind, rain, ice, heat, UV rays, and other constant weather variations that occur with the seasons or even throughout the day. However, in some locations, where temperatures can vary greatly in just a few hours, elongation or contraction can happen in both the cable and its supporting structures, which can affect the conditions of the fibers inside.
Therefore, as always, the choice of cable should take into consideration the local conditions, including the maximum and minimum temperatures, hours of sun exposure, humidity, and so on.
Within the Self-suported category, there are three different types of aerial fiber optic cables:
ADSS (All Dielectric Self-supporting Cable): It’s a very strong cable that can support its own weight. It can be deployed to up to 1000 meters between support poles, which is a considerably long extend ability. The fibers inside this type of aerial fiber optic cable are completely loose in the core of it to prevent attenuation, due to possible cable deformations. They are standard for accompanying power transmission lines.
Fig 8: The name of this self-supported cable comes from its strength element being located on the exterior of the cable, forming a figure of the number 8 when cut. This strength member can be made of steel or dielectric material. This type of aerial fiber optic cable can withstand very high-tension forces and extends up to 180 meters. Figure 8 cables can be divided into three types, but all three have high mechanical strength, water protection, and high UV resistance:
GYTC8S type: The fibers are protected in a corrugated steel tube for great mechanical strength.
GYXTC8Y type: It has a loose tube with water blocking and waterproof properties.
GYXTC8S type: The fibers are protected in a corrugated steel tube for high mechanical strength, and it also has loose tubes with water-blocking and waterproofing properties.
OPGW (Optical Ground Wire): These are fully metallic cables, capable of holding large quantities of fibers inside. These aerial fiber optic cables are used in power lines and work for both data transmission and protection against lightning strikes.
What are the Main Benefits of Aerial Fiber?
The main advantages of aerial fiber optic cables are:
These can be easily installed due to being very lightweight and flexible (except for OPGW cables).
Often, in the path we want make, there already exist electrical or other network poles, and we can take advantage of these existing paths.
Aerial fiber optic cables allow for covering long distances fast, sometimes in just a day’s work.
However, they also have disadvantages like the visual pollution they cause to landscapes, increased risks of contact due to exposure (some cables are hit by hunting shots), and impact from the environment, that translate into greater maintenance needs for these cables.