Here is a good overview of some of the benefits software defined radio can bring to wireless. Imagine a radio that can span a 7 gigahertz range just by the function being performed. You could have a cellphone that makes cell calls then cuts over to Wi-Fi then to WiMax then to Bluetooth then to who-knows-what? - All in ONE chip built in to a device! The power savings and functionality are mind-blowing.
-Mike O. The Polite Radio Mark Frauenfelder Wed May 04 08:00:00 GMT 2005 http://www.thefeature.com/article?articleid=101589 [...] As the years went on, radio became even more polite: it learned to divide channels into sequential time slots, and assign different devices to coded channels. Then, in 1991, a computer scientist named Joseph Mitola coined "software radio" to describe wireless devices that were capable of transceiving over different frequencies and protocols simply by changing the software that ran the devices. It was a good idea -- instead of having to uses multiple chipsets to be able operate in different networks, a software radio could emulate whatever chipset the system required to work with it. [...] Conventional voltage-controlled oscillators (VCOs) have a tuning range in the neighborhood of 20 percent, but the COGUR VCO can double or halve its midpoint frequency. If the midpoint frequency is, say, 5 gigahertz, it can shift up to 10 gigahertz or down to 2.5 gigahertz. [...]
