The FCC’s OBI issued a paper in June called Spectrum Analysis: Options for Broadcast Spectrum, OBI Technical Paper No. 3 [3.5 mb pdf]. The agency has a goal of recouping 120 MHz of spectrum (20 TV channels).
BroadcastEngineering has thus far printed two articles of analysis by Phil Kurz in what will be a multipart series analyzing the report.
August 5, 2010: New approach seeks to optimize DTV spectrum allotment.
In a related Congressional development, Sen. Jay Rockefeller has introduced a bill authorizing voluntary incentive auctions of TV spectrum, and last month Rep. Rick Boucher and Rep. Cliff Stearns introduced a similar bill in the House. Link: BroadcastEngineering. --Dennis