| 摘要 |
A satellite signal receiver (12) includes an input demodulator (7) followed by a Viterbi decoder (26) and a Reed-Solomon decoder (28). A received signal is encoded with information including error-representative information, and exhibits an error correction code rate which is a function of the power level of a satellite transmitted signal. The demodulator (7) produces control signals representing the presence or absence of synchronism with the received signal, and signal quality (e.g. signal-to-noise ratio). The Reed-Solomon decoder (28) produces a control signal indicating whether or not error detection and correction is occurring properly. These control signals are sensed by a control network to change the code rate of the Viterbi decoder if necessary. |
