§  101.117   Antenna polarization.

   Except as set forth herein, stations operating in the radio services
   included in this part are not limited as to the type of polarization of
   the radiated signal that may be employed. However, in the event
   interference in excess of permissible levels is caused to the operation
   of other stations as a result of employing other than linear
   polarization, the Commission may order a licensee to change its system
   polarization to mitigate the interference. No change in polarization
   may be made without prior authorization from the Commission. Unless
   otherwise allowed, only linear polarization (horizontal and vertical)
   shall be used. For LMDS systems, unless otherwise authorized, system
   operators are permitted to use any polarization within its service
   area, but only vertical and/or horizontal polarization for antennas
   located within 20 kilometers of the outermost edge of their service
   area.

   [ 68 FR 4957 , Jan. 31, 2003]