Boosting Cell Signals for a Better-Connected Campus
When cellular carriers cannot solve coverage problems on campus, universities turn to signal boosters to fill in the gaps.
With 40,000 students and a campus that stretches three miles in all directions, the University of Houston (TX) is big – and cellular reception is a big issue.
"Cellular signal penetration problems are caused by a range of factors," explained Rashad Fogle, telecommunications analyst for UH. "For example, even though we're below sea level, the campus is built with a lot of basements. Most basements are impenetrable to cell signals. There are also other common areas that are underground, rooms with no windows and buildings that were built with materials that cause signal problems."
Cell carriers provide theoretical coverage based on mathematical calculations and the number of cell towers a carrier has in any given geographical area. However, in many situations, these calculations do not take into account real-life obstructions, including construction materials and terrain.
UH is using signal boosters to fill in the gaps. Essentially, the technology captures weak or blocked signals and boosts the signal strength to create a more robust, reliable connection. A booster may capture the signal from a cell tower, increasing the strength of that signal and rebroadcasting it within a defined area. It may also capture the signal from a cell phone, boost that signal, and retransmit with enough power to reach back to the cell tower. Cellular boosters work for all carriers, and each booster unit can support multiple simultaneous users.
There are a number of different buildings on the UH campus that have been transformed by signal boosters, according to Fogle. These former no-signal-zone areas range from underground classroom and conference areas to whole buildings. The biggest implementation was a seven-story student dormitory, built to "green" specifications with materials that make it more energy-efficient.
"This recently built 1,100-bed dormitory had signal issues on all seven floors," explained Fogle. "It's an example of how a building's makeup creates a problem with receiving cell signals. The concrete walls, floors and ceilings, and the energy-efficient tint on the windows, are very energy-efficient – but cell phone signal suffers in this environment. I was tasked with finding a solution for this problem."
Fogle brought in Powerful Signal Business Solutions, which installed the SureCall Force5 cellular booster system. The Force5 pumps signals to 12-18 antennas at one time, has a range of up to 20,000 square feet and can support up to 100 simultaneous users/devices — regardless of carrier. "Green" now means "Go" for cellular users residing in the dorm.
Although the UH campus is served by the major cell providers – including AT&T, Verizon, Sprint and T-Mobile — connection issues have occurred with all the carriers. While there are things individual carriers can do to help solve signal problems, it was not feasible for UH to involve every carrier in boosting coverage for every area.
Another potential solution — a distributed antenna system (DAS) — was also out of reach for UH, at least for now. "Our long-term goal has been to acquire a distributed antenna system that could be centrally located and distributed throughout campus using our network infrastructure," Fogle noted. "This has not been an option in the past due to cost, which would be at least $2 million for our facilities. We needed a solution that was cost effective, more universal to cell carriers, as well as durable." With cellular amplification systems, the UH IT Telecom Team provided cell coverage for all of the school's problem areas for about one-eighth of that cost.
"Our use of signal boosters has resulted in an 80 percent increase in cellular signal coverage," said Fogle. "This is important today with the high volume of cell phone usage by everyone, including faculty, staff and students. It provides an additional communication solution that is especially ideal in case of an emergency."
Most common emergency information at UH is communicated via e-mail, but text messages handled via cellular phones are becoming more and more popular, Fogle explained. Now that cell amplification systems are in place, he said, signals can reach users in those areas that once were degraded or where the cell signal was completely blocked.
Fogle noted that the signal boosters were "very easy to install." He was able to learn the system "in a matter of minutes," and found it very user-friendly. "Of course," he added, "it helps to have some cabling background."
For IT administrators considering signal boosters, Fogle has the following recommendations:
- Double-check connectors when installing. It's very easy to overlook a connector during the installation process — and if you don't do it properly at the start, you can waste a lot of time tracing bad connections, Fogle pointed out. To save additional time troubleshooting after the system is turned on, make sure that all connectors are crimped and seated properly.
- Take the time to choose the best possible area for the antennas. This makes a big difference in the performance delivery of the amplification system, said Fogle. Choose the best possible location for your donor (external) antenna. The signal in this area should have the greatest possible cell reception. The broadcast (internal) antenna should be installed in desired areas for signal delivery. With a properly installed donor antenna, the signal should be sufficient for cell service in your desired area.
- Don't overrun the length of any branch of the system, as this leads to poorer performance. Signal booster systems are designed based on floor plan, building composite and landscape. Within the design, there are specific distance requirements for the cabling to antennas and distribution equipment to provide the best possible service delivery. If you have to improvise and deviate from the design, it's best to consult your designer for any changes that may be required elsewhere in the design, advised Fogle — otherwise, you may not get the desired cell signal you need for service delivery.
- Make sure you use the most knowledgeable facility resource when designing the layout of your system. Fogle uses UH's building managers to assist when researching the best locations for the amplifiers and the donor and broadcast antennas. The building managers usually know the best closet space to house the equipment, and are aware of any shortcuts in the building's infrastructure, he explained.
- Balancing the system's output is critical to the level of service delivered, said Fogle. Once the system is in place and turned on, it's important to check the signal in desired areas. Depending on your amplifier, you should be able to turn different frequency filters on or off for desired service delivery in the given areas.
Another Reception Issue Resolved
At the University of New Mexico in Albuquerque, faculty and staff rely heavily on their cell phones — but indoor cell coverage has been a challenge.
"The University of New Mexico has many older buildings made with a lot of concrete and rebar, where we were not getting reception," said facilities manager Jeff Kleeman. "We also have a lot of subterranean areas, and reception there was non-existent."
Kleeman and his team talked to representatives from all four major cell carriers. The carrier reps said they could put antennas on top of some of the buildings but that would probably not help — the signals would still not reach inside the buildings. They said the concrete, steel and building materials used to make buildings LEED [Leadership in Energy & Environmental Design] certified would effectively block the signal.
"As for the subterranean areas of the buildings," Kleeman recalled, "well, forget about it. The carriers said we had to grab that signal outside the building and bring it inside."
Kleeman concluded that carriers are mostly interested in spreading their signals over large geographic areas. "I guess their business model does not include developing in-building solutions."
That's when Kleeman and his team called on Repeater Store (now Waveform.com), a SureCall installer. "We put antennas on the roof to grab the outside signals, connected them to the boosters, then connected inside antennas to the boosters and placed them in the areas where coverage was needed."
The result: "Exactly what we had hoped for," said Kleeman.
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