As the wireless industry comes of age, upgrades are necessary to keep existing, legacy infrastructure in working order and compatible with emerging wireless communications technologies. Those upgrades and enhancements start with the very foundation of wireless communication, wireless tower sites.
Physical tower upgrades occur mainly for structural reinforcement, so a tower can support more carriers’ equipment, making it capable of enabling communications for more wireless consumers. But carriers are finding it increasingly necessary to upgrade aging backhaul networks that lie beneath the ground at cell sites.
Carriers approach tower upgrades in cycles, depending on whether quality or coverage is most important at the time, said Dan Adickes, vice president of sales and marketing for WesTower Communications Inc., formerly the construction arm of SpectraSite Inc. “The animal kind of went dormant for a while, now it’s coming back to life,” said Adickes of the recent increase in interest in upgrading towers to improve quality of service.
Above-ground upgrades can be tricky because towers are really just tons of steel. Structural engineering firm Paul J. Ford and Co. and infrastructure solution provider AeroSolutions L.L.C. are working together to offer structural upgrades to existing wireless towers. Paul J. Ford provides analysis services for structural upgrades to its tower-owner customers’ existing structures as well as for designing new towers for companies like Sprint PCS, American Tower Corp., SpectraSite and Crown Castle International Corp.
The upgrades are implemented through a partnership with AeroSolutions, which developed AeroForce Systems, an upgrade solution that uses a carbon fiber material allowing for nearly transparent upgrades without welding. The material, used to strengthen foundations, towers and antenna-supporting water towers and rooftops, as well as for ground panels and maintenance buildings at cell sites, weighs a fraction of traditional steel, so working with it requires less manpower and less time.
WesTower is licensed to install AeroSolutions’ upgrade solution and has its own patent-pending upgrade solution, the TMR (Thread-bar Monopole Reinforcing) Solution. TMR offers carriers a cost-efficient way to strengthen monopoles, also without welding and without affecting tenants, so they can accommodate additional antenna equipment, Adickes said.
In addition to physical tower structures, carriers are upgrading their backhaul networks, which typically consist of copper T1 lines lying beneath cell sites. San Francisco-based FiberTower, founded in June 2000, has been busy rolling out its business plan to build, operate and manage microwave backhaul networks at cell sites. Traditional copper backhaul networks present problems for both wireless carriers and tower companies, according to David Leeds, co-founder and vice president of marketing of FiberTower.
Wireless carriers pay huge amounts to telco companies for use of the copper lines, often the top cost in their operating budgets, and tower companies-accustomed to having control over everything at their sites-have no say when it comes to telco-owned copper backhaul. Carriers can save money and improve networks without spending capital using FiberTower to manage a microwave backhaul solution, Leeds said, and the company pays tower owners to be at their sites.
FiberTower offers carriers a complete backhaul solution consisting of a network based on point-to-point licensed microwave technology, as well as software to manage and monitor the network. The company is financed primarily by the wireless tower industry, according to Leeds, who declined to name specific companies involved. It has signed national agreements with two of the big six wireless carriers. Its first network is live in Dallas. The company’s strategy is to build out “dense” networks, by building coalitions of tower companies and carriers in specific markets, said Leeds.
Carriers need to upgrade backhaul networks in order to keep up with increased minutes of use and emerging technologies like GPRS, 1x and Wi-Fi, said fSona Communications Corp.’s Michael Corcoran.
On average, each carrier uses one T1 line per cell site. To optimize their networks, each carrier needs up to four T1 lines per site, according to Corcoran. Instead of using additional T1 lines, which likely would cause a multitude of problems-not the least of which would be sacrificing reliable communications-Corcoran said carriers should opt for broadband backhaul solutions, including microwave and free-space optics.
FSona, which specializes in free-space optics, is a proponent of using the technology in combination with microwave for backhaul networks. Wireless carriers increasingly are implementing such combination systems, Corcoran stated. “We can go where microwave cannot go.” Because it only travels shorter distances (it only covers up to four kilometers), free-space optics transmits no RF signals and does not require any spectrum. That means it can easily fill in the gaps for microwave backhaul, covering areas like hospitals, which prohibit microwave signals.
Another company, Bayly Communications Inc., is focused on optimizing the existing backhaul system. According to Brian Sherk, sales manager at Bayly, 25 percent to 40 percent of the bandwidth available on most traditional T1 backhaul networks goes unused. Bayly offers products, including its OmniFlex and OmniBranch T1 access platforms that allow carriers to recover that unused bandwidth.
Sherk said Bayly’s six-year-old solutions have become increasingly popular in the past six to 10 months, indicating carriers’ needs to drop operating costs. “They’ve just never looked before,” said Sherk, adding that traditionally, carriers just added new T1 lines as new technologies require without maximizing the bandwidth already available on existing copper lines. Bayly also offers products to optimize microwave backhaul networks.
Before any infrastructure upgrade can ensue, however, carriers have to assess what it will entail. Enter Cramer Systems, which helps wireless carriers develop a detailed model of the physical inventory they have at each cell site, enabling them to discern exactly what upgrades, above or below ground, might be necessary and how they can best be carried out.
“Carriers want to move from reactivity to proactivity,” emphasized Alan Gilbert, spokesman for Cramer. Too often, carriers go into the field to implement upgrades and find that the information from their databases is outdated, giving inaccurate views of the site, and making it impossible to implement changes as planned, according to Ronnie Beggs, Cramer’s wireless product manager.