| 摘要 |
Method for receiving a high-definition television signal using the methods of band separation and subsampling. The physical embodiment of the method can be obtained by converting the radio-frequency signal received into a first intermediate-frequency signal and by separating from the latter a second intermediate-frequency signal and a narrow-band intermediate-frequency signal. The narrow-band intermediate-frequency signal is locked into a given fixed frequency in order to demodulate the second intermediate-frequency signal in a technique by phase displacement in quadrature. The demodulated signal is low-pass filtered and converted into a digital signal in order to separate from the latter a synchronisation signal, an audio signal, a control signal. The digital signal is processed in a high-frequency band on the basis of the control signal, and it is delayed by a given time. The delayed signal is added to the signal processed in the high-frequency band. The added signal is separated into luminance Y and chrominance (R-Y, B-Y) signals so as to be converted into analog signals. <IMAGE>
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