| 摘要 |
PURPOSE:To exactly execute equalization even against propagation distortion having plural fall-in frequencies in a band, by providing plural resonators so that each resonance frequency and Q can be changed independently and simultaneously. CONSTITUTION:An input signal becomes an equalized output signal through an HPF 1, resonators 2, 3, an LPF 4 and AGC amplifier 5. On the other hand, a control port 6 controls a voltage controlling oscillator 7, sweeps its oscillation frequency, and its oscillating output is inputted to multipliers 9, 10 through a limiter 8. In the multipliers 9, 10, input/output signals are multiplied by an output signal of the limiter 8, and outputs of the multipliers 9, 10 are provided to the port 6 through LPFs 11, 13 and amplifiers 12, 14, respectively. As a result, the port 6 detects frequencies f1, f2 of the minimum level and frequency fmax of the maximum level. Subsequently, the port 6 controls the center frequency in each resonator 2, 3 so that it conforms with the frequencies f1, f2, and also controls Q of the resonator so that each level of the frequencies f1, f2, and fmax becomes equal. |
