摘要 |
A satellite communications system comprises a transmitter, a satellite transponder and a receiver. The transmitter transmits an uplink multi-level modulated signal (hierarchical modulation or layered modulation) to the satellite transponder, which broadcasts the multi-level modulated signal downlink to one, or more, receivers. The transmitter includes a repetition coder for repetition coding at least one level, e.g., a lower level, of the multi-level modulated signal. In complementary fashion, the receiver includes a repetition decoder for use in decoding the at least one repetition coded level of the received multi-level modulated signal.
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