| 摘要 |
<p>PURPOSE:To make Fourier transformation strong against a noise and an error by Fourier-transforming oscillation waveform values after storing one, at least, of sampled new oscillation waveform values, and simultaneously, removing one, at least, of old oscillation waveform values. CONSTITUTION:The sampled new oscillation waveform value of every period is stored, and simultaneously, one, at least, of the old oscillation waveform value having been stored is removed, and a complex amplitude value in every sampling period is obtained from the complex amplitude value obtained before from difference between one, at least, of the new oscillation waveform values and one, at least, of the old oscillation waveform values. Then, when an oscillation waveform is synchronized with a sampling section, one, at least, of N pieces of sampled data is remarked, and it is averaged. Thus, since the sampled data is a few, possibility to pick up the noise is reduced, and even though the noise is picked up, it can be eliminated by averaging processing.</p> |
