Microsoft claims new protocol fixes interference problem for white-space devices

Researchers from Microsoft and Harvard University say they have developed a protocol that could be the foundation for new white-space devices.

The researchers believe the protocol could enable devices to avoid interference in white-space spectrum--those unused slivers of spectrum in the 700 MHz band between spectrum used by broadcast TV stations. The FCC approved the use of white-space devices last November on the condition that they don't interfere with nearby services, such as broadcast TV and wireless microphones. White-space devices are supposed to undergo a rigorous certification process before it is authorized. The vision for white space is to create super WiFi technology. The broadcasting industry has vigorously opposed any use of white-space devices, citing interference concerns. It hasn't been satisfied with the FCC's conclusion that interference won't be a major problem.

Microsoft and Harvard researchers presented their ideas this week at the ACM SIGCOMM 2009, a communications conference held in Barcelona, Spain, according to an article published on MIT's Technology Review Web site. The set of protocols are called "White-Fi," which are designed to avoid interference and make efficient use of the white-space spectrum since much of the interference has to do with devices using the same frequency at the same time. The protocol enables each device to evaluate the spectrum around it, discover available frequencies and continually search for interference, the researchers said. Once the interference is found, the protocol enables the device to jump to a different piece of spectrum at any time.

Microsoft recently obtained an experimental license from the FCC to build a prototype White-Fi system on the Microsoft Research Campus in Redmond, Wash., Microsoft researcher Ranveer Chandra told Technology Review. Microsoft plans to share its findings with the FCC.

For more:
- read Cnet

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