| 摘要 |
<p>When a narrow-band digital filter is used for demodulating a signal which has been modulated by using a plenty of sub-carriers, the number of stages is increased, analysis requires a long time, the transmission speed is not increased, and the circuit size is increased. The modulation circuit operation is considered as multiplication of a trigonometric function matrix of each sub-carrier by modulation data matrix and DA conversion of the product. The state of each sampling is expressed by a simultaneous linear equation. For demodulation of this, the simultaneous equation is solved by handling the AD conversion data as a modulation output and the modulation data series as unknown, so as to obtain the demodulation data series. Thus, it is possible to obtain demodulation data series by a comparatively small number of sub-carriers and a small number of samplings. In order to increase the transmission speed and reduce the circuit size, the speed increase of the DA/AD converter the phase amplitude is corrected by applying to the number of over-samplings, thereby improving the transmission reliability. <IMAGE></p> |
