| 摘要 |
PURPOSE:To obtain an optimum equalized waveform by detecting the attenuation amount of the high frequency component to the low frequency component within a frequency band of a digital reproduction signal and controlling the level of the high frequency component to the low frequency component in response to the detected attenuation amount. CONSTITUTION:A digital input signal 1 serves as the input of the cascaded delay units 2 and 3 respectively and is applied to an adder 6 via a variable gain inverting amplifier 8. While the output of the unit 3 is applied to the adder 6 via a variable gain inverting amplifier 9. Furthermore the output of the unit 2 is applied directly to an adder 6. The addition output 7 of the adder 6 is supplied to BPF10 and 11, and the outputs of the BPF10 and 11 are applied to peak detectors 12 and 13 respectively. The outputs of detectors 12 and 13 are used as the input of a coefficient controller 14, and the gains of the amplifiers 8 and 9 are controlled by the control signal of the controller 14. The controller 14 works to secure the coincidence between the low and high frequency components of a reproduction signal. Thus an optimum equalized waveform is obtained. |
