Elements for a year 1995 mobile communications satellite

Achieving compatibility between the different mobile satellite terminals and integration with the existing well developed terrestrial networks (ISDN), are goals that a new mobile satellite system should aim for. Compatibility will certainly reduce the costs of the user terminals and will allow single-loop communication between users of different categories, whereas integration will allow a deeper penetration of the satellite systems into the existing networks, therefore increasing the impact on the users community. The European Space Agency is developing different payload concepts and their associated hardware to serve the above requirements of the next generation mobile communication satellites. These developments are briefly described, with an emphasis on their level of maturity