By Tobias Schubert, Marketing; Major Accounts; EMEA, Carrier Networks at Corning Optical Communications
5G will fundamentally change telecommunications across the world. The implementation of the new standard has already begun in the GCC and now the network operators need to ensure the infrastructure is ready for 5G. The demand for faster connections is growing not only in the industry but also among the public.
The reason for the increasing demand for fiber optic connections among the general public is the growing need for bandwidth as more and more devices are connected to the internet. Consumers expect high quality when streaming movies and music. IoT appliances in households and production facilities are gaining importance and further boosting the growing demand for bandwidth. In order to meet this demand, we require fiber optic connections to the building and into the home or the apartment as they have a technically almost unlimited transmission capacity.
At the same time, telecommunications companies are preparing for 5G. As the demand for bandwidth and lower latencies grows, the infrastructure must be adapted. Copper cables are being complemented or replaced by fiber optical cables because copper will no longer be able to meet these increased requirements in the future.
So the question is: how do you get fiber to people quickly and cost-effectively, no matter where they are?
Why we need aerial deployment
Rural and remote areas are a challenge for the deployment of fiber optic cables: the distances are long and underground installation to the end customer via fiber to the home (FTTH) networks is a major cost factor and very time-consuming. The aerial fiber optic installation offers an alternative installation method for the fast and cost-effective deployment of FTTH connections in the process of broadband expansion. It is considered if underground installation is not possible or very expensive (e.g. in mountainous regions), or if an infrastructure (poles or power towers) already exists. This method is also suitable for temporary applications, e.g. to bridge the time before the next planned road modernization when a cable can be moved underground more economically.
About 80–90% of the total costs to build fiber networks correspond to traditional underground deployment. As the approval and deployment processes are very time-consuming and complex, many large construction companies consider it to be unprofitable. In addition, the underground fiber optic construction requires specialists who are increasingly scarce on the labor market.
Aerial cabling can be a cheaper and easier alternative here. The cables are usually installed on existing infrastructure, such as wooden poles. This existing and constantly growing infrastructure can be leveraged for the installation of fiber optic cables, thus massively reducing costs compared to underground cabling.
It’s all about the right cable design
When deciding which type of cable is right for your application, several factors need to be considered: the desired bandwidth for end customers, how easily network expansion or repairs can be carried out, the necessary certification requirements for installers and the ability to expand the network over time.
We generally choose from two basic network designs:
- Point-to-point deployment on dedicated routes, typically for long distance connections between urban and rural areas with very distant fiber access points
- Point-to-multipoint fiber optic installation in dense urban and suburban environments with multiple fiber access points.
In practice, we often see mixed forms of aerial and underground networks. For some projects, the operators decide to bury the cables in the backbone area and lay the last mile to the customer aerially. Others install the backbone infrastructure on poles and bridge the last mile underground.
Fiber terminations or fiber network distribution points must ensure that the cables can be used independently when they arrive as aerial or underground cables and they should provide capacity for future upgrades, additions or changes to make the networks future-proof.
The different cable types
There are three types of aerial cable designs commonly deployed: full-dielectric self-supporting cables (ADSS), Figure 8 aerial cables and standard outside plant cables (OSP). Before deciding which cable best suits your needs, you should take a closer look at their specific designs and characteristics.
ADSS cables, like the Corning SOLO® ADSS, are suitable for point-to-point connections over long distances in rural areas or for inter-city links. ADSS cables do not require any additional supporting lines (messengers) and are therefore suitable for installation in the vicinity of high-voltage lines up to 12kV in accordance with IEEE 1222 guidelines. As the cables are metal-free, they do not require grounding. This allows for installation in existing power lines and reduces costs.
However, not all ADSS cables are the same: for a long service life without negative effects on the optical transmission performance, ADSS cables must be manufactured using aramid yarns. When temperatures rise in summer, plastic components in the cables tend to expand. Aramid yarn, on the other hand, contracts inside the cable construction, reducing cable sag in summer.
When installing aerial cables on wooden telecommunication poles without any electrical line nearby, Figure-8 self-supporting cables are an alternative solution to ADSS cables. They are manufactured by incorporating an additional steel wire into the cable sheath. It then carries the load of the fiber optic cable when it is installed between poles and prevents an increase in attenuation throughout the life of the cable. Figure-8 cables can be installed with a span of up to 80 meters and require fewer accessories for mounting on the poles compared to ADSS cables. This allows installation costs to be reduced if there are no electrical potentials affecting the optical cable. However, the problem of lightning strikes in the steel wire still persists and must be considered.
OSP cables like SST-Ribbon™ cables are perfect for point-to-multipoint applications in an urban or suburban area. OSP cables are available with armoring or full dielectric construction and can be tied to existing cables or steel messengers. This type of installation is generally preferred when a high fiber count connection is required. The steel messenger is used to support the weight of the fiber optic cable and to withstand weather conditions, thus reducing the load on the optical fibers.
However, if an OSP cable cannot simply be attached to existing cables, the need for a new steel messenger could lead to additional costs. It is also necessary to check that the load capacity of the poles is not exceeded by the new cables. Steel messengers and armored aerial cables also require grounding, which can also lead to additional investments.
5G is coming to the region and the broadband rollout is progressing steadily, but alternative installation methods may need to be considered to make 5G a reality sooner. The deployment of aerial cables will be an essential part of the various cable solutions, especially for remote and rural areas and also for temporary network connections. This way, customers can be provided with fast internet until the cables can be laid underground at a lower cost, e.g. in the course of road modernizations. Aerial cables are relatively easy to install and the infrastructure already exists in many places. Thus, the use of aerial cables speeds up the expansion process at a fraction of the cost. Aerial cabling can play a major role in building a future-proof network supplying all customers with fiber connections, no matter where they are.