A “workable technical solution” that will allow unlicensed TV band devices to share the same swath of spectrum used by TV stations and wireless mics without causing interference to either will emerge if policymakers “don’t pollute” the science behind the issue “with politics,” an FCC commissioner said Monday.
In remarks to the Conference on Spectrum Management in Washington, D.C., Commissioner Robert McDowell discussed the ongoing debate over whether unlicensed RF devices should be allowed to operate on unused portions of the DTV spectrum, often referred to as white spaces.
“If we don’t pollute science with politics, powerful new technologies will emerge and American consumers will benefit as a result,” he said.
The issue of whether such devices should be allowed into the TV band has sparked a battle between incumbent spectrum users — namely TV licensees and wireless mic users and vendors — who wish to protect themselves against harmful interference, and various high-tech companies that desire to use the band for a variety of new devices and services.
Broadcast groups, such as the Association for Maximum Service Television (MSTV), have publicly expressed support for FCC Chairman Kevin Martin’s goal of allowing the use of stationary devices in designated spots on frequencies known not to cause interference to nearby broadcasters. This approach, particularly in rural areas of the country, could usher in broadband Internet access to homes too remote to be connected economically with other alternatives.
However, they reject the idea of “personal, portable” unlicensed devices using white spaces. Such mobile applications would have to rely on questionable spectrum sensing technology to identify frequencies for operation where they did not detect the presence of broadcast and wireless mic signals. If millions of such devices were in the hands of consumers on the move and they failed to adequately detect the presence of TV stations, the future of over-the-air TV broadcasting could be a blank screen, they contend.
In his address, McDowell expressed confidence that inventiveness and technology will solve the problem. “Inventors will continue to invent, and a workable technical solution will develop,” he said.
McDowell told his audience that he has “long advocated vigorous promotion of unlicensed use of the white spaces,” as long as that use doesn’t cause harmful interference.
On July 31, the FCC Office of Engineering & Technology published the results of tests conducted at the FCC Laboratory of two prototype white space devices. In part, it said that “bench testing of the sensing function of Prototype A device found that this device is generally not able to detect DTV signals on any of the tested channels at the -116dBm/6MHz level detection threshold for DTV signals on which the commission requested comment or at the -114dBm level detection threshold suggested by the device’s manufacturer.”
That, along with other findings in the report, threw cold water on the drive for personal portable devices. However, the report also prompted Microsoft, one of the companies providing a prototype, to meet with the FCC and ultimately assert that the device used in the test failed to perform because of a faulty component.
In his comments to the conference, McDowell expressed optimism that a solution will be found, and said he was hopeful that the “unlicensed approach will provide opportunities for American entrepreneurs to construct new delivery platforms that will provide an open home for a broad array of consumer equipment.”
For more information, visit http://fjallfoss.fcc.gov/edocs_public/attachmatch/DOC-276676A1.doc.
