Extensions eliminate cell blind spots

The hills and valleys of Lawrence Berkeley National Laboratory’s campus once presented something of a hang-up for researchers at the Energy Department’s oldest lab. Their cell phone calls would drop inside lab buildings and as they traversed the 200-acre site.

The campus had spotty indoor cellular coverage for two reasons. The cavernous landscape weakened signals from nearby cellular towers, and the lab facilities’ concrete and steel infrastructures obstructed signals. Finding a signal in some rooms was nearly impossible. Buildings on hilltops received good coverage, while buildings deep in the valleys — and sometimes carved into hillsides — had little or no coverage.

“I’d be going from building to building and calls would come in and out, and people couldn’t get in touch with me,” said Stephen Nobles, a project manager in the information technology infrastructure department at Berkeley Lab. “Walking or driving, you definitely would go in and out of coverage. If you found a spot, you’d have to pull over to maintain reception.”

The campus was designed more than 70 years ago, before cellular coverage existed. Now about 3,800 employees rely on mobile voice and text messaging to communicate with one another and the world outside Berkeley Lab as they conduct their unclassified research in disciplines such as integrated computing and nanoscience.

When cell phones became ubiquitous about seven years ago, lab officials realized they needed better reception from area cellular carriers. Cellular One and AT&T Wireless — now Cingular Wireless — proposed deploying an indoor cellular system from in-building network provider LGC Wireless. Because of delays caused by the merger of AT&T and Cellular One, the project did not begin until 2003. Lab officials say the cellular extension was worth the wait.

Overseeing the installation was relatively painless, Nobles said. Within six months, a handful of LGC engineers and lab technicians had installed the network. Nobles’ role was to direct the LGC engineers to areas with poor reception. The engineers determined where to place antennae on the ceilings. “They pretty much did most of the design work,” he said.

The LGC system is akin to a sprinkler system that sprays radio waves. A central source, known as a Cingular base station, transmits radio waves to cell phones campuswide via the indoor antennae. A single antenna can provide cellular coverage for a 10,000-square-foot room or a 125,000-square-foot open area, such as a convention center. Buildings on the Berkeley Lab campus range from the size of portable trailers to facilities of 150,000 square feet. The LGC deployment spans 10 buildings and includes about 100 antennae.

Not all buildings at Berkeley Lab required extra coverage. Some were able to receive signals from the outdoor cell towers.

More extensions coming
The project continues to evolve. As the number of lab facilities grows, more cellular extensions will be necessary. Berkeley Lab officials just deployed the system in a new six-story nanoscience facility called the Molecular Foundry. The structure is in a canyon carved out of the hillside. It had zero coverage, Nobles said.

The project initially hit some minor bumps. The community was concerned about the equipment’s appearance. Although the antennae are small — about a foot and a half wide by four feet tall — the state historical society was troubled by the appearance of plastic equipment on a 1930s stucco building. Nobles and his team solved the problem by painting the antennae to match the building.

There was one other, more pressing concern. Cellular signals can interfere with sensitive lab equipment, such as electron microscopes. Again, the solution was simple. The team moved the antennae a few feet down the hallway, away from the microscopes, to eliminate the interference. One downside to the configuration is that it supports only Cingular subscribers. All laboratory-owned phones use Cingular, but some graduate students and professors from the neighboring University of California at Berkeley use Verizon, Sprint Nextel and other carriers.

Indoor mobile phone networks are a rapidly emerging market, observers say. LGC recently constructed similar cellular systems for several large federal facilities. The Federal Communications Commission’s Washington, D.C., headquarters was outfitted to receive service from Cingular, Verizon, T-Mobile and Sprint Nextel. LGC’s installation at the new U.S. Patent and Trademark Office in Alexandria, Va., supports Cingular, Verizon and Sprint Nextel.

John Spindler, LGC’s marketing vice president, said, “Everybody these days is carrying a cell phone or a BlackBerry or a [personal digital assistant], but as you go deeper into the building, you’re going to have more obstructions between you and the cell tower. Because the coverage isn’t uniform throughout the building,” customers are starting to ask for cellular augmentations, he said.