§  25.261   Procedures for avoidance of in-line interference events for Non
Geostationary Satellite Orbit (NGSO) Satellite Network Operations in the
Fixed Satellite Service (FSS) Bands.

   (a) Applicable NGSO FSS Bands. The coordination procedures in this
   section apply to non-Federal-Government NGSO FSS satellite networks
   operating in the following assigned frequency bands: The 28.6-29.1 GHz
   or 18.8-19.3 GHz frequency bands.

   (b) Definition of "In-line interference events." For purposes of this
   section, an "in-line interference event" is defined as the interference
   associated with an occurrence of any physical alignment of space
   stations of two or more satellite networks with an operating Earth
   station of one of these networks in such a way that the angular
   separation between operational links of the two networks is less than
   10DEG as measured at the Earth station.

   (c) Default procedure. If no agreed coordination exists between two or
   more satellite networks, then the bands will be divided among the
   affected satellite networks involved in an in-line interference event
   in accordance with the following procedure:

   (1) Each of n (number of) satellite networks involved in a particular
   in-line interference event shall select 1/n of the assigned spectrum
   available in each frequency band for its home base spectrum. The
   selection order for each satellite network shall be determined by and
   be in accordance with the date that the first space station in each
   satellite network is launched and operating;

   (2) The affected space station(s) of the respective satellite networks
   shall only operate in the selected (1/n) spectrum associated with its
   satellite network, its home base spectrum, for the duration of the
   in-line interference event;

   (3) All affected space station(s) may resume operations throughout the
   assigned frequency bands once the angular separation between the
   affected space stations in the in-line interference event is again
   greater than 10DEG.

   (d) Coordination procedure. Any coordination procedure agreed among the
   affected operating satellite networks, which allows operations of the
   satellite networks when each network's respective space stations are
   within the 10 degree avoidance angle associated with an in-line
   interference event, shall supersede the default procedure of paragraph
   (c) of this section. Coordination may be effected using information
   relating to the space stations and the parameters of one or more
   typical earth stations. All parties are required to coordinate in good
   faith.

   [ 68 FR 59129 , Oct. 14, 2003]