| 摘要 |
PROBLEM TO BE SOLVED: To provide the digital demodulator in which no absolute phase processing circuit is required. SOLUTION: A known pattern BPSK signal generating circuit 6 generates the same known pattern BPSK signal as a known pattern BPSK signal, in a received digital modulated wave synchronously with the known pattern BPSK signal in the received digital modulated wave. A carrier recovery phase error detection circuit 7 is provided with only a phase error table, where one reference phase in reference phases of a signal point of a demodulated base band signal is used for convergence point. Then a phase error voltage, based on a phase difference between a phase obtained from the signal point of the demodulated base band signal and a phase at the phase convergence point, is given to a carrier recovery loop filter 8, which is enable-controlled, based on the known pattern BPSK signal outputted from the known pattern BPSK signal generating circuit 6, to smooth the phase error voltage and then the carrier is controlled by controlling a frequency of the recovered carrier so that the phase at the signal point comes to the phase convergence point. |
