| 摘要 |
PURPOSE:To simply convert a signal level of a MUSE signal into a prescribed level even when the inputted MUSE signal is either in the AM or AM transmission mode by sharing a waveform equalization filter with the MUSE signal level conversion use for the MUSE signal. CONSTITUTION:A coefficient of a 1st stage coefficient multiplier 12-1 or of a final stage coefficient multiplier 12-n of an adaptive equalization filter 1 for waveform equalization receiving a MUSE signal subjected to A/D conversion is set independently of other coefficient multipliers in the filter 1 at the time of signal level conversion. Furthermore, based on a detection output of a transmission control signal in the MUSE signal, whether the multiplier 12-1 or 12-m is used for waveform equalization or used for signal level conversion is switched. Furthermore, which is the multipliers 12-1, 12-n is used for signal level conversion is switched by comparing the coefficients of the multipliers 12-1, 12-n calculated by a tap coefficient correction circuit 4 according to an output of the waveform distortion detection circuit 3 at the time of the signal level conversion. |
