Signal assessed user terminal system access in satellite communication systems
First Claim
1. A satellite communication system wherein a user terminal is operative to communicate with one or more out of a plurality of satellites;
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
where each of said earth stations is operative, periodically, to provide a broadcast message, via said satellites, which can be received by said user terminal, said broadcast message identifying that earth station from which it originated; and
wherein said user terminal is operative to monitor said broadcasts;
said system being characterised by said user terminal being operative to perform an assessment of the quality of the signal in each broadcast message received;
by said user terminal being operative to establish and maintain a league table based on the assessed quality of the signal in said broadcast messages received from each of said plurality of earth stations whose broadcast messages are audible to said user terminal; and
by said user terminal being operative, when making a request for service from said system, to direct said request to that one out of said plurality of earth stations which is top of said league table.
4 Assignments
0 Petitions
Accused Products
Abstract
A satellite communications system comprises satellites 9A-C, earth stations 7A-E, user terminals 11 and controlling gateways 3 in the form of mobile satellite switching centers 5A-E. Access to and from a user terminal 11 may be gained from and to a terrestrial telephone system 1 by earth stations 7A-E contacting the satellites 9A-C and by the satellites contacting the user terminals 11. The satellites 9A-C periodically broadcast messages indicative of the earth station 7A-E with which they are instantly in contact. The user terminal 11 listens to these broadcasts, assesses the quality of the received signal, and keeps a league table based on an accumulated score allocated to each earth station 7A-E which can be heard. When calling into the system, the user terminal pages earth stations in descending order of score in the league table. When in contact, the user terminal 11 sends the league table to the system. When subsequently trying to contact the user terminal 11, the system uses earth stations in descending order of score in the league table, last received from the user terminal.
14 Citations
27 Claims
-
1. A satellite communication system wherein a user terminal is operative to communicate with one or more out of a plurality of satellites;
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
where each of said earth stations is operative, periodically, to provide a broadcast message, via said satellites, which can be received by said user terminal, said broadcast message identifying that earth station from which it originated; and
wherein said user terminal is operative to monitor said broadcasts;
said system being characterised by said user terminal being operative to perform an assessment of the quality of the signal in each broadcast message received;
by said user terminal being operative to establish and maintain a league table based on the assessed quality of the signal in said broadcast messages received from each of said plurality of earth stations whose broadcast messages are audible to said user terminal; and
by said user terminal being operative, when making a request for service from said system, to direct said request to that one out of said plurality of earth stations which is top of said league table. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
-
8. A method for use in a satellite communication system wherein a user terminal is operative to communicate with one or more out of a plurality of satellites;
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
where each of said earth stations is operative, periodically, to provide a broadcast message, via said satellites, which can be received by said user terminal, said broadcast message identifying that earth station from which it originated; and
wherein said user terminal is operative to monitor said broadcasts;
said method being characterised by including the steps of;
said user terminal performing an assessment of the quality of the signal in each broadcast message received;
said user terminal establishing and maintaining a league table based on the assessed quality of the signal in said broadcast messages received from each of said plurality of earth stations whose broadcast messages are audible to said user terminal; and
said user terminal, when making a request for service from said system, directing said request to that one out of said plurality of earth stations which is top of said league table. - View Dependent Claims (9, 10, 11, 12, 13, 14)
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
-
15. A user terminal for use in a satellite communication system wherein said user terminal is operative to communicate with one or more out of a plurality of satellites;
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
where each of said earth stations is operative, periodically, to provide a broadcast message, via said satellites, which can be received by said user terminal, said broadcast message identifying that earth station from which it originated; and
wherein said user terminal is operative to monitor said broadcasts;
said user terminal being characterised by being operative to perform an assessment of the quality of the signal in each broadcast message received;
by said user terminal being operative to establish and maintaining a league table based on the assessed quality of the signal in said broadcast messages received from each of said plurality of earth stations whose broadcast messages are audible to said user terminal; and
by said user terminal, when making a request for service from said system, being operative to direct said request to that one out of said plurality of earth stations which is top of said league table. - View Dependent Claims (16, 17, 18, 19, 20, 21)
- wherein each of said plurality of satellites is operative to communicate with one or more out of a plurality of earth stations to provide communication between said user terminal and at least one of said earth stations;
-
22. A supervisory earth station, for use in a satellite communication system wherein a user terminal is operative to communicate with one or more out of a plurality of satellites;
- wherein each of said plurality of satellites is operative to communicate with said supervisory earth station and with one or more out of a plurality of other earth stations to provide communication between said user terminal and at least one of said supervisory earth station or said other earth stations;
where each of said earth stations is operative, periodically, to provide a broadcast message, via said satellites, which can be received by said user terminal, said broadcast message identifying that earth station from which it originated;
wherein said user terminal is operative to monitor said broadcasts;
wherein said user terminal is operative to perform an assessment of the quality of the signal in each broadcast message received;
wherein said user terminal is operative to establish and maintaining a league table based on the assessed quality of the signal in said broadcast messages received from each of said plurality of earth stations whose broadcast messages are audible to said user terminal; and
wherein said user terminal, when making a request for service from said system, is operative to direct said request to said supervisory earth station, if said supervisory earth station is top of said league table, or to that one out of said plurality of other earth stations which is top of said league table;
said supervisory earth station being operative to receive said league table from said user terminal and, when subsequently paging said user terminal, being operative to select, in turn, in descending order of assessment, itself or each of said plurality of other earth stations, to page said user terminal until an earth station is found to whose paging said user terminal responds. - View Dependent Claims (23, 24, 25, 26, 27)
- wherein each of said plurality of satellites is operative to communicate with said supervisory earth station and with one or more out of a plurality of other earth stations to provide communication between said user terminal and at least one of said supervisory earth station or said other earth stations;
Specification