| 摘要 |
<p>A circuit arrangement four conference circuits in digital communications systems, particularly in PCM telephone systems, provide digitized voice signals of the conference participants which are added in the conference circuit and are transmitted to all conference participants minus a voice signal generated by the respective participant. In the conference circuit, linear samples are transmitted to a subtracter in a frame-delayed manner by an intermediate memory and are compared by a transverse filter to the sum of all preceding samples respectively multiplied by a correction value derived dependent on the phase position to the sum of a momentary sample. As a result, each conference subscriber receives the sum of the voice signal of all conference subscribers minus his own voice signal, whereby the echo signals of the conference participants are suppressed except for one's own echo signal.</p> |
