Development of an Waveform Equalizer for a MUSE Decoder

Abstract

The MUSE system, a bandwidth compression system for HDTV transmission, employs sub-sampling techniques and transmits picture information as a PAM (Pulse Amplitude Modulation) signal. In order to obtain good picture quality, the cosine roll-off characteristic is applied to the transmission path.
For this purpose, we have developed a waveform equalization circuits that can be built into the MUSE decoder.These circuits consist of an additional A/D converter that operates at twice the sampling rate of the main A/D converter, and a digital filter with variable coefficients to obtain the compensation signal. Equalization is performed by adding this compensation signal to the output signal of the main A/D converter.
Even though the configuration of this equalizer is simple and small scale, it can still satisfy the characteristics required by the actual transmission paths of MUSE signals.