Alcatel Lucent Shrinks Cell Phone Towers

If you've been wondering whether to equip your roving workforce with iPads or other mobile devices, Alcatel-Lucent promises to make mobile computing cheaper, faster, and more readily available wherever you go.

Alcatel-Lucent today is announcing that its Bell Labs unit has invented a replacement for the existing cellular architecture, now showing its age after 30 years of operation without major change, according to Tom Gruba, senior director of product marketing for the company in Naperville, Ill. The next generation of mobile equipment will help suppliers deliver better service, while extending their capacity and coverage.

Alcatel-Lucent's new Light Radio product set can't be compared directly to existing equipment because it decomposes today's cellular architecture and reassembles it in a new, more space- and energy-efficient way, Gruba said in an interview.

Antennas, which used to sit as a lone component atop towers, have been shrunk in size and can now be combined with miniature amplifiers, which enable them to be placed discreetly in many existing locations, such as on a building, street lamp, or a flag pole, without the need for large towers filled with antenna spars. That move has already been afoot for three years as the first components became available, Gruba said.

At the same time, the new infrastructure separates the digital processing unit, which used to be closely linked to the amplifiers in a hut at the foot of a cellular broadcast tower, and relocates new Freescale-produced processors in consolidated facilities, such as a carrier's local switching and routing center.

This reconstruction of the cellular network results in a doubling of the capacity available to any given user, while cutting in half the energy consumed, claimed Gruba. The Light Radio product set will allow phones and other mobile devices to become smarter and more active without threatening the capacity of the cellular network, as they are starting to do today. With the rapid growth of smartphones, existing cellular providers were not going to be able to build towers with equipment huts at their feet fast enough to keep up, he said.

The equipment huts at the foot of today's cellular towers are used to house the amplifiers and digital signal processors. These, too, have been deconstructed. In the past, the amplifiers were connected to the antennas at the top of the tower by coaxial cables. On a 300-foot tower, that meant half the signal wattage was lost by the time it reached the peak. By moving the amplifier to the antenna and combining them as a new broadcast unit, this power loss is avoided. The antenna/amplifier combination is connected to the digital processor, now moved out of the hut to a central processing facility, by fiber optic cable. Fiber optic signal attenuation is less than coaxial cable's for the distances involved. The product set was dubbed Light Radio because of its lighter impact on the environment as well as for the fact that fiber optic light waves are carrying signals between antenna towers and consolidated processing centers. The antennas themselves have been improved so that they can broadcast a signal in the direction of the customer instead of in a 360-degree arc, the way present cellular systems do. The actual arc is 120 degrees, Gruba noted, and the antenna can switch direction in the midst of a call if the customer moves to the edge of the arc. The focused broadcast is another power and capacity saver, he said.

In addition, multiple towers may serve the same customer at the same time instead of one tower needing to own the customer, with the others contending in wasted signals for ownership. "Coordinated, multi-point antennas work in concert," noted Gruba. So a customer seeking information off a complex Web site can receive headers from one tower, ads from another, and content from a third, rapidly populating the screen of his device.

"The customer sees he's getting his bits faster. He doesn't care where they came from. There's more speed and volume. It will be more like a wired experience," Gruba said.

No carriers have implemented the new architecture yet. Alcatel-Lucent is just coming to market with the first product set that can be used to implement it. China Mobile and other industry leaders have backed the creation of the product set, he noted. Other telecommunications manufacturers will be bringing out their own product sets in the future, he acknowledged.

The new antennas may be configured to broadcast either 2G, 3G, or 4G signals, or any combination of two of them, and the antennas with their amplifiers may be built out in columns, like Lego blocks. The design will help ensure that carriers in the future will be able to place the right amount of broadcast power where it's needed, without a massive tower.

The approach will reduce the cost of cellular towers by 66% and the expense of sending field technicians on service calls by 60%. Energy costs for the same broadcast output will be reduced by 51%, he claimed.

Over time, the innovations represented by the architecture behind Light Radio will allow the full convergence of voice and data onto IP networks, Gruba predicted.