ntial route to SDR is being pioneered by the open source- based GNU Radio project. Eric Blossom, the project's leader, believes that SDR makes a lot of sense from an open-source standpoint, since it would make phones and radios infinitely compatible and flexible. An SDR radio could, for example, let users simultaneously listen to an FM music station, monitor a maritime distress frequency, and upload data to an amateur radio satellite. Developers could also create a "cognitive radio"-one that seeks out unused radio frequencies for transmissions. "That could go a long way toward solving the current spectrum shortage," says Blossom. The GNU Radio project also wants to throw a virtual monkey wrench into the efforts of big technology and entertainment companies to dictate how, and on what platforms, content can play. By creating a user-modifiable radio, Blossom and his colleagues are staking a claim for consumer control over those platforms. "The broadcast industry has a business plan that fundamen- tally hasn't changed since 1920," he says. "I don't see any constitutional guar- antee that some previous business plan still has to be viable." Work on the GNU Radio project's first design-a PC-based FM receiver- is complete, with an HDTV transmitter and receiver in the works. Yet devel- opers still must overcome power consumption issues and other hurdles before software-defined radio becomes practical. Blossom estimates that it will take about five years before SDR hits the mainstream. 6.3 ULTRAWIDEBAND RADIO Today's relatively poor-quality wireless local area networks (WLANs) could soon be replaced by a far more sophisticated technology. Ultrawideband (UWB) promises high-bandwidth, noninterfering and secure communications for a wide array of consumer, business, and military wireless devices. A team of Virginia Tech researchers is attempting to take UWB to a new level. Michael Buehrer and colleagues William Davis, Ahmad Safaai-Jazi, and Dennis Sweeney in the school's mobile and portable radio research group are studying 