FCC Concerned about Wireless Broadband Use of Vacant TV Channels
At their Thursday open meeting, the FCC commissioners adopted a Notice of Proposed Rulemaking (NPRM) to allow wireless broadband services to use vacant TV channels. While the text of the Notice of Proposed Rulemaking has yet to be released, an FCC News Release FCC Proposes Rules to Facilitate Wireless Broadband Services Using Vacant TV Channels said the NPRM proposes to allow two categories of devices to use vacant TV channels. One category would include low power "personal/portable" unlicensed devices that would be used in the same manner as Wi-Fi home networks. The second category would consist of higher power "fixed/access" devices that would generally be operated from a fixed location and used for services such as broadband Internet access. According to the FCC, these devices, operating under Part 15 of the FCC rules, would not be allowed to cause harmful interference to other service, adding that the NPRM proposed specific technical requirements "to ensure that TV reception is not impaired."
In comments filed in response to the FCC's Notice of Inquiry, broadcasters expressed concern about the potential for these devices to interfere with TV reception. MSTV, NAB and the Association of Public Television Stations (APTS) pointed out in their Joint Comments that unlicensed devices are unlikely to include the technology to avoid interference with TV reception and that there is very little "unused spectrum in the broadcast band. The MSTV/NAB/APTS comments noted that "the television band will be in a crowded, fluid and fragile state during the digital transition." They also expressed concern that low power devices could interfere with high power DTV transmissions in areas were the TV signal is weak due to terrain, buildings, foliage, distance from the transmitter or, for indoor reception, building construction materials.
There was also concern that consumers would blame broadcasters if their unlicensed wireless devices stopped working when a DTV station increased power. MSTV/NAB/APTS explained, "The burdens created by such a de facto allocation of responsibility can be substantial, as when a local broadcaster felt it had to replace 2,000 garage door openers disabled by the broadcaster's new DTV signal."
Sinclair Broadcasting pointed out another problem in its comments. "Given that over-the-air DTV receivers have proven incapable of providing adequate reception in the present interference environment, it is a certainty they will not be able to operate when unlimited numbers of unlicensed transmitters are operating in the same environment. Equally disturbing, the Consumer Electronics Association (CEA), the representative of electronics manufacturers that has stated that over-the-air television is not a worthwhile market, is on record applauding the Commission's decision to explore new unlicensed uses of TV broadcast spectrum." Sinclair urged the FCC to take expedited action to adopt mandatory DTV receiver performance standards or "voluntary standards accompanied by a meaningful labeling regime..." instead of giving consideration to sharing of the TV broadcast spectrum.
Cox comments of Cox Broadcasting said, "The Commission should establish a timetable for testing and evaluating unlicensed operation in the broadcast spectrum coordinated with the close of the DTV transition." Cox did not oppose the concept of allowing unlicensed devices to operate in the broadcast band, but noted that the FCC has every reason to presume widespread commercial success of these devices. Since the FCC has not permitted widespread unlicensed use of TV channels before, there is little experience with how TV receivers will be affected by it.
Some FCC commissioners seemed concerned about the potential for TV interference as well. In his statement on the NPRM, Commissioner Michael J. Copps said, "I want to encourage the Bureau and my colleagues to be vigilant to ensure that we have the investigative and enforcement resources and plans in place as we pursue more and more complicated spectrum arrangements. We may allow unlicensed operations in this band. And we have already allowed other tightly packed licensed and unlicensed use in other bands. Given the interference concerns these actions create, we must be able and ready to conduct independent harmful interference tests, and to act decisively when harmful interference has occurred."
Commissioner Kevin J. Martin released a statement concurring in part with the decision to release the NPRM: "While I am pleased that this proceeding has the potential to encourage new and innovative unlicensed services, I remain concerned about the proceeding's impact on the broadcasters and their transition to digital television."
Commissioner Jonathan S. Adelstein was more descriptive in his statement. "Unlicensed operations should not be permitted in the television bands if they appear to be likely to cause harmful interference to TV reception, and I fully support our request for comment on how best to ensure that such interference is not caused by the operation of unlicensed devices. The American people care a lot about the quality of their television reception. Television broadcasts are viewed by people as perhaps the most sacred use of public spectrum. Their TV is not to be trifled with. We will hear an earful from consumers if this is not done right." He added, "it is worrisome that we are undertaking this proceeding right in the middle of our important digital television transition. I have lingering concerns about the wisdom of allowing unlicensed operations in the vacant television bands before the DTV transition is complete, and I encourage commenters to fully address this timing issue and any problems that it creates."
Two other comments filed in the Notice of Inquiry Notice of Inquiry that I noticed provided additional insight into the concerns about interference from unlicensed devices in the TV bands are the joint comments filed by several state broadcaster associations and broadcast companies and the comments of The Port Authority of New York and New Jersey. The Port Authority was concerned about interference to its radios in the 470-512 MHz band. You can view all the comments by going to the FCC Search for Filed Comments page and entering 02-380 in box number 1, "Proceeding" and clicking on "retrieve document list."
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