A radiocommunication service between Earth stations and one or more space stations, which may include links between space stations, in which:
information relating to the characteristics of the Earth and its natural phenomena is obtained from active sensors or passive sensors on Earth satellites;
similar information is collected from airborne or Earth-based platforms;
such information may be distributed to Earth stations within the system concerned;
platform interrogation may be included.
This service may also include feeder links necessary for its operation . [ NTIA ] [ RR ]