More like a PC
The first cell phones relied on dozens of hardware components. In the past 15 years, programmable chips have been added, but their function is set immutably at manufacture. Today, dedicated, single-purpose chips do most of the work in mobile phone handsets and base stations; these chips are made as simple as possible to keep costs down.Given the mishmash of conflicting standards and the uneven advent of the next generation of broadband wireless, manufacturers such as Motorola are starting to see dedicated components as a liability. A manufacturer that guesses wrong about the future standard will find itself with a lot of useless junk in its warehouses. As Ken Riordan, of Motorola’s Personal Communications Sector in Libertyville, IL, puts it, “If you commit your solution to hardware, and you get it wrong, then you’re going to be in a very jeopardized situation.”
So more-general-purpose software that can be reprogrammed looks appealing. No one understands the trade-offs better than Joseph Mitola III, a radio engineer whom many insiders perceive to be the central innovator in the field. Early in life, Mitola became fascinated with computer code; he learned Fortran while attending high school in Providence, RI, in the 1960s. When he got to college-Northeastern University in Boston-he says he was “one of the few who knew how to program anything.” Mitola had also tinkered with radios. Combining both interests led to a career creating top-secret radio designs for the military-including the first software-defined radios, which were for military use (see “The Military Seed” sidebar). Indeed, the commercial wireless industry learned of the technology in the early 1990s mainly through Mitola’s papers and lectures. His military bosses cleared these for public release, figuring the military could benefit if the commercial world pushed the technology further and brought costs down.
The problem Mitola was trying to solve was similar to the situation that would arise if you had to put a new circuit board in your PC every time you wanted to do a different task-say, switch from Web browsing to a spreadsheet. You’d eventually run out of space inside the box. The same holds true for cell phones. “If you want to cram in four more functions, it means each device has to be about a quarter the size it was before,” says Mitola, now at the McLean, VA, office of MITRE, a nonprofit R&D consultancy. But, he adds, chips aren’t shrinking rapidly enough to make that possible, given the many standards and functions the wireless revolution demands.