White space use OK'd

The FCC has released a report and proposed rule making in its 2004 proceeding dealing with the authorization of unlicensed devices to operate in the spectrum currently set aside for TV broadcasting.

Low-power devices

In the report, The FCC authorized low-power devices to operate in the TV band, but only after the end of the DTV transition in 2009. The agency will not authorize the use of personal portable devices at this juncture. Only fixed, or stationary, low-power operations will be permitted. The use of personal portable devices would likely pose a greater risk of interference, so the FCC is seeking further comment on this issue.

The commission has also prohibited low-power devices from operating on Channel 37 (to protect the radio astronomy services) and Channels 52 to 69 (to protect the wireless and public safety services authorized to operate on these channels).

And the FCC has prohibited, until the end of the DTV transition in February 2009, the marketing of portable or fixed devices. It wants to protect TV stations finalizing their DTV transition as well as allow itself time to adopt the technical rules under which the new unlicensed service will operate. The marketing of these devices will ultimately be covered by the new rules.

The commission questions whether the use of the TV spectrum for these fixed low-power devices should be on a licensed or unlicensed basis. The FCC prefers the unlicensed use of the spectrum, given the wide range of the spectrum's availability (rural vs. urban) and the difficulty that would be involved in creating priority rights to the spectrum among licensees.

Use of unlicensed devices

Additionally, the commission is seeking comment on the appropriate method for determining whether a particular swath of spectrum is available for use and whether unlicensed devices would cause harmful use to TV stations in the vicinity.

The commission has proposed three possible solutions:

  • enabling the devices to sense whether the spectrum is available;
  • professionally installing the devices, equipping them with GPS, and guiding them by a database of existing TV stations; or
  • establishing a control signal program in which existing FM, TV and CMRS providers would continuously broadcast a signal providing a list of channels available to devices, and limiting the device to operate only on one of those channels.

There is only one other sensing system currently authorized for use in the 5GHz band, but there are substantial differences between that already authorized use and the use under consideration. Therefore, the FCC is asking for testing to show that a sensing system could work in the TV band.

The commission is also seeking comment on the best method for making these systems work. The FCC wants comments on the appropriate threshold for sensing devices and on whether to protect TV channels that are adjacent to the spectrum to be used for the unlicensed devices. Also, the FCC is considering whether these unlicensed devices will be required to use transmit power controls that will limit the transmit power to the minimum necessary.

The FCC is also considering excluding the devices from operating on Channels 2 to 4. With respect to possible standards and limits for out-of-band emission levels, the FCC has asked whether it would be appropriate to use the same standards currently applied to other unlicensed devices.

The commission is also asking the public to substantiate its claims of interference or no interference with data and test results. While the FCC will be conducting tests to determine whether any of the methods for avoiding harmful interference will work, it is also seeking studies from the public.

Harry C. Martin is the past president of the Federal Communications Bar Association and a member of Fletcher, Heald and Hildreth PLC.


Jan. 10 is the deadline for placing children's TV programming reports (Form 398) in the public files of all full-power and Class A TV stations. Also, on Jan. 10, all commercial TV and Class A stations must place in their public files their certifications with respect to compliance with commercial limits during programming for children ages 12 and under.

Jan. 10 also is the date by which all TV and Class A stations must place their quarterly issues and program lists in their public files.

Feb. 1 is the deadline for renewal applications for TV, TV translator, LPTV and Class A stations in New Jersey and New York. TV stations in those states also must file biennial ownership reports by Feb. 1. TV stations, LPTV stations that originate programming and Class A stations must file EEO program reports by Feb. 1.

Send questions and comments to:harry.martin@penton.com