The FCC voted Nov. 4 to authorize the use of unlicensed devices in TV white spaces.
The move opens the band to a variety of consumer devices and services, such as improved wireless broadband connectivity and peer-to-peer devices, that will create “a Wi-Fi on steroids,” in the words of FCC Chairman Kevin Martin.
Authorizing unlicensed devices to operate in the band has been highly contentious, pitting the interests of broadcasters, sports leagues, theater owners and others against high-tech companies like Microsoft and Google seeking to take advantage of the inherent strengths of the TV band. At issue has been whether or not technologies such as spectrum sensing and geolocation technology can provide adequate safeguards to protect TV signals and wireless mic transmission from harmful interference emanating from white space devices.
As of Nov. 4, the FCC had not published the new rules; however, according to a commission press release, the rules approve fixed and personal/portable unlicensed devices and specify the use of geolocation technology and access to an Internet database of full- and low-power TV stations and cable headends, as well as spectrum sensing, to protect against interference. To protect wireless mics from white space device interference, the rules will allow venues where wireless mics are frequently used, such as stadiums and theaters, to be registered in a database, as well as spectrum sensing technology. The rules also make white space devices subject to FCC Laboratory certification.
The commission’s authorization of white space devices “imperils” TV reception “to satisfy the ‘free’ spectrum demands of Google and Microsoft,” according to comments from David Donovan, president of the Association for Maximum Service Television (MSTV), released to the press.
Donovan pointed to four weaknesses in the commission’s decision, including:
- The operation of white space devices at 40mW on first adjacent channels will cause interference that affects millions of over-the-air TV viewers.
- The power levels will cause direct pickup interference for millions of cable subscribers.
- The “complete failure of spectrum sensing” in FCC Lab tests contradicts the conclusion in a report on the second phase of commission testing of white space devices that there has been “proof of concept.”
- “Live, on-the-spot” TV crews using wireless mics to cover sports and breaking news lack adequate protection.
Following the vote to authorize the devices, the FCC’s five commissioners released individual statements on their decision. While most acknowledged the possibility of harmful interference from white space devices, they expressed confidence in the conclusion of the FCC engineering staff that authorization done prudently would not disrupt incumbent users of the TV spectrum.
Commissioner Deborah Taylor Tate said she “placed much faith” in Julie Knapp, chief of the FCC’s Office of Engineering and Technology, and his staff of engineers. “Their recommendations, while always useful in any rulemaking, played an especially persuasive role in my final decision to support this item,” she said. “I have been assured by Chief Knapp and our top engineers that the risks of interference have been appropriately considered.”
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