| 摘要 |
PURPOSE:To obtain an object amplitude characteristic more accurately by adding a difference between amplitude characteristics of an amplitude input means and a Fourier transformation means to the inputted amplitude characteristic, obtaining again a transfer function, applying inverse Fourier transformation to obtain a filter coefficient and repeating the processing above until a difference reaches a prescribed range. CONSTITUTION:A desired amplitude frequency characteristic and a phase frequency characteristic are inputted by an amplitude input means 11 and a phase input means 12, and a new amplitude frequency characteristic and a new phase frequency characteristic are obtained based on the calculation using the amplitude phase deviation frequency characteristic obtained from the analyzing a data inputted from a signal input means 18 or the amplitude phase deviation frequency characteristic stored in a memory. Then an impulse response is calculated by an inverse Fourier transformation means 15 applying inverse Fourier transformation to a transfer function having the amplitude frequency characteristic and the phase frequency characteristic and the impulse response obtained by a setting means 16 is set to a transversal filter 17 as a filter coefficient. Thus, a desired characteristic is obtained. |
