New Active DAS Hybrid Solves In-Building Cellular Coverage Challenges for Small to Medium Enterprise

Cel-Fi QUATRA delivers uniform cellular coverage in venues up to 200,000 sq. ft. at a fraction of the installation time and cost of other solutions.

Leave a Comment
New Active DAS Hybrid Solves In-Building Cellular Coverage Challenges for Small to Medium Enterprise

Achieving uniform in-building cellular coverage in small to mid-size enterprise (SME) spaces is a common challenge for integrators. Solutions such as active DAS are usually too much – technically and financially – for the SME budget. BDAs (bi-directional amplifiers) and femtocells are generally too limited in their coverage capacity (15,000 sq. ft. or less) and can interfere with a carrier network, resulting in customers less than satisfied with the installation.

In some cases, multiple small cells are being used to tackle the mid-market space. However, this solution brings its own challenges, not the least of which are potential problems relating to backhaul, interference between small cells, cabling, and coverage optimization. In these scenarios, careful planning and integration is necessary to ensure there is dominance over the macro signal at the building perimeter, and no interference between the small cells or other elements on the network. The added complexities can lead to significant installation costs for customers.

To address these issues, a unique active DAS hybrid technology was introduced this year for venues up to 200,000 sq. ft. This new in-building enterprise cellular solution, Cel-Fi QUATRA, operates either in off-air mode or can be integrated with carrier small cell equipment and operated in distributed small cell mode, creating a SupercellTM. A Supercell (i.e. a large single cell versus multiple small cells) provides uniform access to the capacity introduced by the small cell. Supercells are inherently uncomplicated from a planning and deployment point of view, because they use a combination of RF over Ethernet (RFoE) and self-optimizing technologies. Installation of remote radio units is made easier with the inclusion Power over Ethernet (PoE), eliminating the need for power outlets at each node.

Since this active DAS hybrid does not require fiber, or complex RF surveys and design, it is much simpler and more cost-effective to install. As it is also self-configuring and self-optimizing, it can be installed and maintained with basic IT and cabling skills.

Because it falls under carrier-specific guidelines for regulatory certification, the active DAS hybrid delivers up to 100dB of gain when deployed in off air mode, providing 1000 times more signal than typical BDA-based systems that can only provide 70 dB of peak gain. At the same time, the stronger signal is not subject to the typical power loss (attenuation) found with coax cables since the hybrid’s signal is all digital.

Solving Cellular Coverage Problems at 2-1-1 San Diego

2-1-1 San Diego chose Cel-Fi QUATRA to solve its cellular coverage problem when it moved into a new 30,000 sq. ft., two-floor, concrete office building and some executives began to experience dropped calls.

2-1-1 San Diego connects more than 6,000 health and disaster services to provide vital food, housing, and other special needs to seniors, vets, children, and others at risk within the community. Although it has a contact center that is powered by landlines, 2-1-1 San Diego otherwise considers itself a BYOD organization where executives rely on their cell phones for conducting conversations. In addition to its own 160 employees, it has partner agencies that are co-located in the same building, as well as meeting rooms that are used by community stakeholders. The poor cellular coverage was interfering with operations.

“Because we operate a Connection Center, we have partner agencies co-located with us. We also have 12 meeting rooms that we allow community stakeholders to meet in,” said Peter Battistel, Vice President of Technology at 2-1-1 San Diego. “We wanted to be able to provide the same level of indoor cellular service [as they had before the move] for the thousands of guests we host each year.”

2-1-1 San Diego’s configuration consists of one Network Unit (NU), which is the hub of the system and provides the donor signal, and four Coverage Units (CUs), serving as the remote radio units that rebroadcast the donor signal. A MIMO Panel Antenna was installed to enhance the donor signal. The system was configured to operate off air, distributing the external macro network signal throughout the building into areas it didn’t reach previously.

“Currently, two of the CUs are located in areas that we lease to other tenants,” explains Battistel, “but we have the flexibility to re-deploy them as needed, and re-position them as we expand. This really enables us to maximize the value of the original investment. We are getting ready to expand our office space, and we will be able to easily re-position the CU’s for better coverage in the new space.”

2-1-1 San Diego contracted an installer to run Cat 5e cables between the two floors of the building. The following day, Cel-Fi QUATRA was up and running within hours. The installation consisted of:

  1. Using the test mode on a smartphone, the installer measured the cellular signal levels within the building to determine the areas where the best coverage existed and where coverage was needed most.
  2. Using this information, a plan was determined for the best location of the NU and external antenna where the off air signal was the strongest, and the best locations of the CUs to blanket the entire building.
  3. With the planning done, the contracted installers ran the CAT 5e cables.
  4. The NU was then mounted in a discreet location above the ceiling tiles. The external antenna was mounted inside a window.
  5. The CUs were placed in various locations on both the upper and lower floors. As previously mentioned, the locations could be flexible since the units were powered via the ethernet cables and there was no need for electrical outlets because PoE.
  6. The LAN management port on the back of the NU was connected to the LAN to enable communications with the Cel-Fi WAVE platform that allows Cel-Fi QUATRA management and maintenance from a computer or mobile device.
  7. The last steps were plugging in the NU to the power source, and provisioning the system.

Depending on the size of an installation and number of systems involved, integrators can complete a Cel-Fi QUATRA installation within a day. This can be done at lower cost for the customer, using fewer resources than a typical DAS installation. For integrators that means a faster turnover and return on investment, not to mention a welcome range of new market opportunities that were previously out of reach for mid-size enterprise budgets.

DOWNLOAD THE WHITEPAPER, Cel-Fi QUATRA In-Building Enterprise Cellular System, for a full understanding of how Cel-Fi QUATRA can be easily deployed to deliver high quality signal for enterprise customers with venues up to 200,000 sq. ft.