In a Public Notice released yesterday, the Federal Communications Commission asked for comments on several possible plans for reorganizing the spectrum currently used by television broadcasters. Initial comments are due June 14, with reply comments due June 28.

Under a statute passed last year, broadcast television stations will be allowed to voluntarily participate in an auction of their spectrum to mobile broadband providers, after which the FCC will involuntarily repack remaining television stations into a smaller television spectrum band.

The FCC’s initial proposals on how to conduct the incentive auction and repacking drew extensive comments. The FCC has continued to gather input from interested parties, including at a May 3  public workshop on how the new 600 MHz wireless band should be organized.

In yesterday’s Public Notice, the FCC noted widespread support among broadcasters and wireless companies for the general principle of a “Down from 51” band plan, in which the FCC would clear TV spectrum from Channel 51 down. The uplink band would occupy the higher portion of the cleared spectrum (adjacent to the current 700 MHz uplink band), while the downlink band would occupy the lower portion of the spectrum. The uplink and downlink bands would be separated by a duplex gap.

However, yesterday’s Notice expressed concern that this version of the band plan would not allow enough flexibility to maximize the amount of new spectrum available for mobile use if different amounts of TV spectrum are cleared in different markets. The Notice asked for comments on three variations on the “Down from 51” band plan:

  • “Down from 51 Reversed”: Unlike the original “Down from 51” plan, in this version the downlink band would occupy the higher portion of the cleared spectrum (adjacent to the current 700 MHz uplink band), while the uplink band would occupy the lower portion of the spectrum. Guard bands would be needed to separate the uplink and downlink bands and to separate the compressed TV band from the new uplink band. The Notice suggested this “Reversed” plan would allow for more flexibility between markets regarding how low the new uplink band can extend.
  • Down from 51 with TV in the Duplex Gap: This proposal retains the structure of the original “Down from 51” proposal, with the uplink band occupying the higher portion of the 600 MHz band. However, in markets where relatively few TV broadcasters give up spectrum some TV stations would be placed in the gap between the new uplink and downlink bands. The Notice recognizes “that some commenters have concerns about allowing high power services to operate in the duplex gap.” A joint filing by the National Association of Broadcasters, AT&T, Intel, Qualcomm, T-Mobile, and Verizon Wireless opposed placing broadcast stations in the duplex gap.
  • Down from 51 TDD Approach: Instead of allocating different uplink and downlink frequencies, this approach would convert cleared TV spectrum into a single band for mobile broadband, which would relying on Time Division Duplexing (TDD) to separate upstream and downstream traffic. In contrast, mobile carriers’ comments have argued that the FCC should provide paired uplink and downlink frequencies, as in the original “Down from 51” proposal.