(a) In general
Nothing in subparagraph (G) of section 309(j)(8) of this title or in section 1452 of this title shall be construed to prevent the Commission from using relinquished or other spectrum to implement band plans with guard bands.

(b) Size of guard bands
Such guard bands shall be no larger than is technically reasonable to prevent harmful interference between licensed services outside the guard bands.

(c) Unlicensed use in guard bands
The Commission may permit the use of such guard bands for unlicensed use.

(d) Database
Unlicensed use shall rely on a database or subsequent methodology as determined by the Commission.

(e) Protections against harmful interference
The Commission may not permit any use of a guard band that the Commission determines would cause harmful interference to licensed services.