Fiber And Power – Better Together

Connectivity for remote radio units (RRUs) at a cell site requires optical fiber for the data and power conductors to supply the power. The two different media types can be kept separate—by bringing the fiber up the tower or along the rooftop in one cable sheath and using a separate cable running in parallel to support the power—or the power and fiber can be combined into one compact cable. CommScope provides both options as part of our HELIAX® FiberFeed solution. However, after examining the applications for each, it appears that using a single cable approach has many advantages:

• Reducing the total number of cables makes it easier and faster to install, whether hoisting up the tower through a monopole or connecting to distributed RRUs at the corners of a rooftop.

• Reducing the number of cables helps limit tower loading levels, simplifies and speeds installation, and reduces the space taken up in cable trays and within the shelter.

• Use of a hybrid trunk cable may also greatly reduce monthly leasing costs if the building owner charges by the cable or by the volume of space the cable consumes. While leasing costs are not a factor everywhere, they can be a significant concern in the United States and parts of Europe and Africa. In some cases, the leasing cost could be as high as $100 USD PER month PER cable. That can really add up over time.

To quantify the expected costs for separate and hybrid cable deployments, CommScope looked at material and labor costs incurred during installation including fiber, power cables, conduit, and accessories. Then we added in the operational expenses and expected savings based on system design. In one 3RRU tower example, the expected savings PER site over a five-year period was about $1,800 when a hybrid cable solution was utilized over separate cables. A potential savings of $180,000+ over a 100 sitescan be quite exciting for an operator.

CommScope supplies hybrid FiberFeed cables with steel or aluminum armoring that protects the cables against crushing forces, theft, rodents, or birds. This eliminates the need for a protective conduit, reducing the installation time as well as labor and materials costs. Adding spare optical fibers and the use of a junction box can allow for upgrades without having to pull in a new cable. Simply utilize the spare fiber and/or replace the short jumper, and changes to your site are made at little additional cost.

For a more in-depth look at the hybrid vs. separate cable comparison, review the white paper HELIAX FiberFeed Solutions: Reduce total cost of ownership for remote radio unit deployments.