Digital transmission of hierarchical HDTV, EDTV and SDTV TV signals - converting analogue picture and sound signals to digital and removing redundancy in source coder

摘要

The method involves converting picture and sound input signals at a transmitter from A/D and removing redundancy is in a source coder (11). After this, the signal bits are protected in an unequal error protection (UEP) coder (12) according to their importance. The TV signals hierarchically formed in the coders (11,12) are multi-level coded, multi-resolution modulated and frequency demultiplexed to be transmitted after D/A conversion. At the receiver, the transmitted signals are converted back from A/D and are inverse frequency demultiplexed with the help of channel state information (CSI). The signals are then demodulated in a multi-resolution demodulator (23) and then decoded in a multi-stage decoder (24). The data is then processed in a UEP decoder (25) specific to each receiver and a source decoder (26) by D/A conversion to HDTV, EDTV or SDTV signals. ADVANTAGE - Detects desired signal from received signal including three qualitative different TV signals.