Satellite communication system with variable rate satellite link diversity

Abstract

A satellite communication system includes Earth-based terminal and a satellite constellation in non-geosynchronous Earth orbits. When two or more satellites are within range of a first Earth-based terminal, the station requests a communication link with the first satellite at a first data rate. If the first satellite will accept data transfer at the first communication rate, the first Earth-based terminal transmits data to the first satellite at the requested first data rate. If, however, the first satellite will not accept data transfer at the requested first data rate, the first Earth-based terminal transmits a first portion of the data to the first satellite at a second data rate and transmits a second portion of the data, different from the first portion of the data, to the second satellite at a third data rate. The first and second satellites relay the respective data portions to a second Earth-based terminal, either directly or via additional satellites. The second Earth-based terminal reassembles the first and second data portions to recover the original data. The data transfer may be unequal error correction encoded data whereby the second Earth-based terminal may recover the original data from only a portion of the received error correction encoded data.