Protection areas. The geographic regions where U.S. Department of Defense meteorological satellite systems or National Oceanic and Atmospheric Administration meteorological satellite systems, or both such systems, receive signals from low earth orbiting satellites. Also, areas around NGSO MSS feeder-link earth stations in the 1.6/2.4 GHz Mobile-Satellite Service determined in the manner specified in 25.203.
47 CFR § 25.103
Terms with definitions including the (RR) designation are defined in the same way in 2.1 of this chapter and in the Radio Regulations of the International Telecommunication Union.