传输线的反射干扰

在数字信号处理系统中,时钟信号和数字信号传输因传输始端和终端阻抗不匹配而引起反射干扰,使传输信号的波形出现上冲、下降和振荡。为了抑制这种因阻抗不匹配引起的反射,本文首先从产生这种反射的原因和造成的重大危害分析,提出了反射干扰这一亟待解决的问题;接着从传输线的阻抗特性以及阻抗匹配原理出发,提出了始端和终端阻抗匹配原则,最后给出了几种减小和抑制反射干扰的方法,实践证明使用阻抗匹配这一方法在减小反射干扰是十分有效的。

Reflection interference of transmission line

In digital signal processing system, the clock signal and digital signal transmission cause reflection interference due to the transmission beginning and the terminal impedance mismatch, so that the transmission signal waveform appears on overshooting, the drop and the vibration. In order to suppress the kind of impedance mismatch caused by the reflection, First, the article introduces the mechanism of the reflection and the significant hazard, put forward the problem of reflection interference which is urgently awaits to be solved; Then embarked from the transmission line impedance characteristic as well as the impedance matching principle,proposed the beginning and the terminal impedance match principle, gave several kinds reducing and suppressing the launch interference;Finally,the paper gives a few method to reduce and to suppress the reflection disturbance. The practice proved that use impedance matching this method was reducing the reflection disturbance is very effective.