FCC proposal could boost Wi-Fi

With the Federal Communications Commission proposing to nearly double 802.11a’s available bandwidth, Wi-Fi is on course to become as available as the air it travels through.

Posted last week, the FCC proposal would add 80 percent (255MHz) to the 300MHz of spectrum currently available in the 5GHz band. The additional spectrum would reside in the middle band, from 5.470GHz to 5.725GHz.

The change would offer many major benefits, according to the FCC.

“The additional bandwidth means you can have higher density of use in a given geographical area because there is much more spectrum available. It can also be channelized in many ways,” said Edmond Thomas, chief of the office of engineering and technology at the FCC in Washington.

The bandwidth proposal would increase the number of channels 802.11a can operate on to 24. At present, IEEE 802.11b has three channels available; 802.11a has 11.

The added spectrum would also match the 5GHz middle band currently allocated in Europe.

“The Europeans decided to use the middle band to get out of the way of radar,” said Craig Barratt, CEO of Atheros, a Sunnyvale, Calif.-based manufacturer of IEEE 802.11x chip sets.

Under the FCC guidelines, additional spectra must use DFP (Dynamic Frequency Protection) so that when a WLAN detects radar using the same band it can switch to another channel.

The FCC chose the same band as Europe's in order to have overlapping bands throughout the world, according to Ken Dulaney, chief wireless analyst at Gartner in San Jose, Calif.

“This simplifies things a lot. If you buy a radio in a country that doesn’t have support for that band, you can’t use it,” Dulaney said.

Given the proposed increase in spectrum, companies would have more flexibility in allocating specific channels for particular applications.

“If you have enough channels set aside for dedicated use, your QoS [quality of service] problems are gone,” said Leigh Chinitz, CTO of Proxim in Sunnyvale, Calif.

Specifying channels will also make the use of VoIP (Voice over IP) far more practical, Chinitz said, adding that VoIP requires the WLAN to offer continuous coverage and high capacity.

“Voice over IP will be carried over wireless LANs by allocating a couple of channels just for VoIP,” Chinitz said.

The proposed specturm addition is also receiving a warm reception from Cisco Systems. Christine Falsetti, Cisco’s director of wireless and mobility marketing, said the FCC’s decision to make the 5.4GHz band usable in an unlicensed way is a positive step.

“Allowing access to this spectrum allows more channels and more innovation,” Falsetti said.

But Gartner’s Dulaney believes the FCC proposal does not go far enough. Dulaney conceded that, in the short term, the increased number of channels would ease conflicts between competing networks but added that the open bands, IEEE 802.11x, are too open.

“We need an unregulated technology in a regulated band,” Dulaney said.

There are a number of other issues surrounding the FCC proposal that could delay deployment of devices that would be capable of accessing the additional spectrum.