一种结构新颖的数字PABX会议电路

数字交换系统中实现会议电话比在模拟系统中要困难得多。因为PCM数字语音信号是非线性的,因而不能象在模拟系统那样直接将与会者的语音信号相加,而需要作特殊处理。本文简要介绍数字会议电话的原理及其实现方法,并就会议电路设计中常遇到的问题进行讨论。文章以总线TDM数字PABX为基础,对一个中规模会议电路的设计提出了一种新的话音开关型会议电路,并给出了其硬件框图和软件流程图。

A Novel Conference Circuit for Digital PABX

In analog switching system conferences' voice signals cart be added direct to implement conference. But the implementation of conference in digital switching system is more difficult than that in analog switching system, ecause PCM digital voice signals are nonlinear signals and can not be added direct to each other. This paper briefs the principles of digital telephone conference and the implementation techniques. Some problems about conference curcuit design are discussed in this paper, too. We have designed a new type of voice switch conference curcuit for a middlesized conference based on TDM bus digital PABX and the hardware and software flow chart of the circuit are presented in this paper.