| 摘要 |
PROBLEM TO BE SOLVED: To enhance the carrying performance and the convenience of the receiver by providing a PSK demodulator applying PSK demodulation to a received signal, a Viterbi decoder and a high efficiency decoder decoding the video signal. SOLUTION: At a transmitter side, an analog video signal is converted into a digital signal, the signal is high-efficiency-coded, that is, an information amount is reduced and the resulting signal is convolution-coded for error correction, and the resulting data are used to apply PSK modulation to a carrier and the modulated signal is sent to a receiver side via a satellite. At the receiver side, a PSK demodulator 24 applies PSK demodulation to a received signal, a Viterbi decoder 25 corrects the error of the signal by Viterbi decoding, that is, the convolution code is subject to maximum likelihood decoding by the Viterbi algorithm and the resulting data are high-efficiency-decoded by an image high efficiency decoder 27, that is, the original data are obtained from the data whose information has been reduced and the original digitized video signal is decoded. |
