Patent ID: 6181913
Filing Date: 2001-01-30
Classification: H04B

Abstract:
A method for establishing a connection in a satellite system comprising at least one base station for transmitting and receiving electromagnetic signals, at least a first terminal for transmitting and receiving electromagnetic signals, at least a second terminal for receiving electromagnetic signals and at least one satellite with at least one transponder for receiving electromagnetic signals and for retransmitting the received signals, with the frequency of the retransmitted signals being shifted with respect to the received signals, wherein said method comprising the steps of:providing a base station having a database with frequencies including available frequencies and engaged frequencies for communication between said terminals,establishing a connection via the satellite between the first and second terminal;transmitting continuously information from said base station to the satellite for establishing a connection, said information being transmitted on a reference and control carrier wave for retransmission by the satellite, and said information including at least the available frequencies for communication between terminals;receiving the reference and control carrier wave retransmitted by the satellite at the first terminal, whereafter using the received information for selecting at least one frequency available for communication, which selected frequency will be used for a desired connection with a particular terminal;transmitting by said first terminal an operating carrier wave on the selected frequency to the satellite for retransmission by the satellite; andreceiving the operating carrier wave coming from the first terminal by the base station, retransmitted by the satellite, determining on the basis thereof that the selected frequency is in use, adjusting accordingly the database with available frequencies for communication between terminals, and adjusting accordingly the information about the available frequencies for communication between terminals that is transmitted on the reference and control carrier wave.