In today’s culture, wireless rules. WiFi-enabled laptops easily connect to Internet hotspots, prevalent in most cities, and cell phones are virtually ubiquitous. But while much of the technology in these devices is advanced, the radio chips that transmit and receive those wireless signals are, for the most part, still based on an older, highly inflexible model: they’re hardwired with access to only a single kind of wireless frequency, such as WiFi or cellular or GPS.
In recent years, researchers have been working on a wireless chip that can do it all: tune into television and radio stations, GPS, cellular signals, WiFi, and WiMax–or even unlock your car door. The trick is to use software to modify the radio hardware, a concept known as software-defined radio (SDR).
Some of the pioneering research on SDR is happening at Lucent’s Bell Laboratories, a facility that’s invented a number of the wireless technologies used today. Bell Labs’ researchers are now developing SDR for base stations, the wireless hubs that communicate with devices.
Currently, it’s expensive to deploy and install the base stations that route wireless signals from, for instance, Cingular, Verizon, or Sprint, to their customers. And when the station’s wireless technology needs to be updated, the companies have to redeploy and reinstall the radio technology. By using software-defined radio, however, the hardware could be easily and inexpensively brought up to speed by simply tweaking the software. In other words, these more-flexible base stations could be upgraded quickly–possibly leading to fewer dropped calls, more reliable signals, and extended ranges.
Tod Sizer, director of broadband wireless research at Bell Labs, and a speaker at Technology Review’s Emerging Technology Conference today, discussed software-defined radio with our editors.
Technology Review: The term “software-defined radio” is kind of clunky, and not too descriptive to people who aren’t familiar with it. What’s your cocktail party definition of the technology?
Tod Sizer: It’s the ability to take a radio [in a cellular base station] that is doing an application that you define today, and tomorrow you can reconfigure it to do something different. That’s one model of software-defined radio. There’s another model, and it’s that you have a single radio [in a handheld device] that has both Bluetooth and [Wi-Fi] 802.11, for instance. We know what those standards are today, but you want to have one radio that can do both. That’s about reconfiguring immediately where the radio can either be one or the other. A lot of software-defined radio has also been pushed strongly by the military, which wants a radio that can communicate with different types of radios, such as those used by the Marines, the Coast Guard, or firefighters. It’s a very important problem and one that the military has pushed as they’ve been a supporter of software-defined radio.