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一、前言由PCM端机送出的双极性半占空矩形脉冲经过光端机——光纤——光端机的传输系统要受到衰减、失真和干扰,波形严重畸变。这样的波形无法直接识别判决。除了针对衰减加以放大外,还必须针对其频率响应失真进行均衡。波形均衡的目的是要在判决点获得容易检出的均衡波形。波形均衡时必须选择判决点信噪比最大的波形均衡函数。同时,为减少噪声影响,还必
I. INTRODUCTION The bipolar half-duty rectangular pulse sent out by the PCM terminal machine undergoes the attenuation, distortion and interference of the transmission system of the optical fiber terminal-optical fiber-optical terminal unit, resulting in serious distortion of the waveform. Such a waveform can not directly recognize the decision. In addition to amplifying the attenuation, it must also be equalized for its frequency response distortion. The purpose of waveform equalization is to obtain an easily detectable equalized waveform at the decision point. Waveform equalization must be selected to determine the maximum signal to noise ratio waveform equalization function. In the meantime, in order to reduce the influence of noise, it is also necessary