Is Wi-Fi Heading Down the Wrong Track?
May 09, 2002
Complaints and petitions to the FCC from users of the same 2.4GHz band that is used by 802.11 devices seek to derail expansion of wireless networks.
In March, Federal Communication Commission (FCC) Chairman Michael Powell told an audience at the annual PC Forum that 802.11 is heading for a "meltdown" as the number of unlicensed devices skyrocket. The head of a group advising the government on managing the radio spectrum predicts a "train wreck" between licensed and unlicensed devices.
Dewayne Hendricks, chairman of the Spectrum Management Working Group, says he will recommend the FCC adopt measures allowing devices to "peacefully co-exist in unlicensed spectrum." Hendricks is also CEO of the Dandin Group, a proponent of Ultrawideband (UWB) technology. The FCC recently approved the limited use of UWB.
The 2.4GHz band, one area where 802.11 devices are permitted to operate, is considered experimental spectrum, so use of the airwaves is not licensed by the FCC. Amateur radio enthusiasts allege the number of 802.11 products are growing as quickly as the level of interference the equipment is producing. Users of offending Wi-Fi gear will have to either eliminate the interference or shut down, according to Hendricks' interpretation of FCC regulations.
Hendricks, an avid supporter of amateur radio, points to a Feb. 8, 2001 case where Wireless Internet Service Provider (WISP) Darwin Networks was required to eliminate interference produced by 802.11b access points at a Dallas, Texas location. The Wi-Fi equipment was interfering with a licensed amateur TV station operating on the same 2.4GHz band.
Although licensed amateur radio is conducted under the FCC's Part 97 rules, ham radio folks also operate in the 2.4GHz area alongside 802.11 gear. The American Radio Relay League (ARRL), a group of about 175,000 licensed U.S. radio operators, petitioned the FCC in February this year, saying the regulatory agency does not have the authority to permit unlicensed devices to interfere with radio services. The group has said that if denied they would go to the U.S. Court of Appeals in Washington, D.C.After television stations in San Francisco reported an increase of background interference from 802.11b devices, the FCC in August 2001 contracted with the Naval Post Graduate School in Monterey, Calif. to produce a noise study. The study was scheduled for release March 20, 2002, but the FCC informed us it is on hold due to other priorities.
Despite a claim by Hendricks that the FCC's consumer complain hotline was "going all the time," a new report by the FCC listing the most common consumer complaints did not include any instances of 802.11 interference. Thomas Wyatt of the FCC's Consumer Government Affairs Bureau told 80211 Planet he was unaware of complaints involving 802.11 interference.
Hendricks says one reason for complaints about interference surrounding Wi-Fi devices is a lack of information. Consumers calling the FCC are often "mirandized" as to their lack of recourse when it comes to interference degrading their wireless service. As Wi-Fi devices evolve from technical to consumer-oriented, there is an increasing misunderstanding of how common household items such as microwaves and cordless phones can cut a WLAN's data speed from 11 Mbps to 1 Mbps, says Hendricks. "Wi-Fi is at the bottom of the heap" when it comes to remedying an interference problem, says Hendricks.
Although the chairman of the FCC working group labels 802.11 as a technology "stuck in time" and "just a bump in the road" of technological progress, Dennis Eaton, chairman of the Wireless Ethernet Compatibility Alliance (WECA), couldn't disagree more.
Eaton says charges of interference are outweighed by all the benefits of Wi-Fi devices, including broadband Internet access. Eaton says his group is filing a response to ARRL's petition. Eaton claims the Wi-Fi standard includes built-in interference protection.
While there is a "potential for interference to go up," Eaton says a recent gathering at Networld+Interop of 500-700 people all on 802.11b using 12 to 20 access points suffered no noticeable degradation due to interference.
This isn't the first time 802.11 technology has been charged with interfering. Sirius Satellite Radio Inc. earlier this year asked the FCC to reduce the power of 2.4GHz devices, saying emissions from in-car Wi-Fi and Bluetooth gadgets could cost the satellite radio industry $3 billion in lost signal strength. To date, the FCC has not responded to Sirius.