资 源 简 介
Many signals are digitally generated or transmitted as squarewaves. It is often desirable to convert these signals into sinewaves. For example, the 350Hz, 440Hz, 480Hz, and 620Hztelephone supervisory tones transmitted over fiber-opticsmay appear at curb-side as square waves. To be used intelephone equipment it is desirable to convert the squarewaves into low-distortion sine waves. This can be done witha simple filter.
