§  25.261   Sharing among NGSO FSS space stations.

   (a) Scope. This section applies to NGSO FSS operation with earth
   stations with directional antennas anywhere in the world under a
   Commission license, or in the United States under a grant of U.S.
   market access.

   (b) Coordination. NGSO FSS operators must coordinate in good faith the
   use of commonly authorized frequencies.

   (c) Default procedure. Absent coordination between two or more
   satellite systems, whenever the increase in system noise temperature of
   an earth station receiver, or a space station receiver for a satellite
   with on-board processing, of either system, ΔT/T, exceeds 6 percent due
   to interference from emissions originating in the other system in a
   commonly authorized frequency band, such frequency band will be divided
   among the affected satellite networks in accordance with the following
   procedure:

   (1) Each of n (number of) satellite networks involved must select 1/n
   of the assigned spectrum available in each of these frequency bands.
   The selection order for each satellite network will be determined by
   the date that the first space station in each satellite system is
   launched and capable of operating in the frequency band under
   consideration;

   (2) The affected station(s) of the respective satellite systems may
   operate in only the selected (1/n) spectrum associated with its
   satellite system while the ΔT/T of 6 percent threshold is exceeded;

   (3) All affected station(s) may resume operations throughout the
   assigned frequency bands once the threshold is no longer exceeded.

   [ 82 FR 59986 , Dec. 18, 2017]