FCC Releases Channel Repack Analysis, Updated OET-69 Software

WASHINGTON — TV regulators have once again updated the software they will use to repack TV stations into the spectrum that remains after next year’s incentive auctions, concurrent with the release of a repacking analysis and related data. The Federal Communications Commission has issue the second update of its TVStudy software, the program based on OET-69, the agency’s methodology for calculating a TV station’s coverage area, plus a 37-page Technical Appendix for how it could be applied.

“One of the key advantages of the TVStudy Version 1.2 software is its ability to easily replicate multiple stations to generate various nationwide scenarios,” the commission said. The user interface was updated, as well as the software’s ability to generate “pairwise” interference data files. These pairwise files are described as “yes-or-no determinations of whether interference is predicted from one television station to another at a particular location,” according to the Appendix. The criterion used to make these determinations is reception by “the same specific viewers for each eligible station.”

This criterion is derived from the commission’s October 2012 Incentive Auction Notice of Propose Rulemaking, which laid out three possible options for meeting the Congressional mandate of making “all reasonable effort” to preserve TV station coverage areas and populations served as of Jan. 3, 2012. (The date Congress passed the Spectrum Act.)

The first option limited new interference to half a percent or less for a population served as of Feb. 22, 2012. Noting that this could change which households experienced interference, the second option was to preserve service to the “same specific viewers.” This would presume the same areas of interference, but potentially by different stations, after a repack. The third and most restrictive option was to allow only the same amount of interference between the same stations. (An addendum to option No. 3 allowed for a 2 percent increase in interference.)

In the NPRM, the commission made clear that it preferred the first approach because it provided the most flexibility in a repack, and met the Congressional mandate by preserving service “to approximately the same number of viewers. The National Association of Broadcaster opposed the method because it would potentially reduce a station’s geographic reach.

In the TVStudy extrapolation described in the Technical Appendix, the commission used Option No. 2—the same specific viewers—but emphasized that it do so for illustrative purposes only.

“The commission has made no decision on them yet,” the Notice stated.

In addition to tweaking the TVStudy software, the commission’s Office of Engineering and Technology consolidated other input data, including Canadian and Mexican TV allotments, as well as domestic licensing information, in a “format that can be used more easily with the updated software,” the commission said. Using the data, the software can calculate which stations can be assigned to which channels, and which ones cannot be located on the same or adjacent channels in neighboring markets.

TVStudy Vers. 1.2 has several functions not available in the previous release, including the ability to:

  • Automatically conduct pairwise studies;
  • Define parameters of Mexican allotments that lack height and power data in the commission’s database;
  • Automatically invert negative electrical beam-tilts that would otherwise cause inaccurate predictions of coverage and interference;
  • Choose the contour level within which Longley-Rice propagation analysis independent of the Longley-Rice parameters;
  • Add Desired and Undesired stations independently and at any time;
  • Choose which output files to create;
  • Generate a summary output file comprising the results of multiple scenarios;
  • Generate cell-level point coordinates.

The new version no longer requires the command line on Macs.

The commission said the information in the Public Notice and the Technical Appendix could be used to determine the feasibility of moving TV stations during bidding in the reverse auction—the process for broadcasters to assess demand for their spectrum.

“Such a ‘feasibility check’ could be conducted rapidly during the course of bidding in the reverse auction because it would only require determining whether a channel assignment is feasible for a set of stations, not that it represents the optimal channel assignment,” the commission said. “Optimization analysis is time-consuming; conducting it during the course of bidding in the reverse auction would restrict the commission’s auction design options.”

The feasibility data could be used to optimize channel assignments after the fact, the commission said. Optimization could be used in a sealed-bid auction to “determine which bids to accept in order to obtain a given amount of spectrum at minimum cost.” The Notice stressed that such scenarios are theoretical, and that “bidders need not know or master the technical details” to participate.

Additional repacking components, such as algorithms related to how bids will be selected and channels assigned, will be released “in the coming months,” it said. The final design will be approved by the full commission.

The Public Notice, “Incentive Auction Task Force Releases Information Related to Incentive Auction Repacking,” is here.
The Technical Appendix is here.

Be on the look-out as well for Doug Lung’s coverage at RF Technology.

Also see…
April 26, 2013:
FCC Releases Updated OET-69 TVStudy Software
“This update addresses an issue with calculation cell indexing that can result in the population of some cells not being correctly considered, and which may cause the program to crash in unusual instances.”

February 6, 2013:NAB—OET-69 Update Injects Legal Uncertainty
Insiders say wagons are circling over the new methodology for predicting TV station coverage and interference.

February 5, 2013:
FCC Reveals Crucial Piece of TV Channel Repacking Method
The Federal Communications Commission has quietly revealed what amounts to its methodology for repacking TV channels in the post-incentive auction spectrum band.