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一、概述所谓“基带”就是一个基本频带的缩写。一个由信息转换过来。信号一般不会有一个严格的正弦或余弦信号,它的频率成分也不是一个单一的频率,而是一个频带。对于数据通信系统中所传输的一些电压或电流脉冲,在没有进行调制以前是一些直流脉冲,直流脉冲不仅包含直流成分,还有很多不同频率的交流成分,这些交流成分中有基波和无数次谐波。这些脉冲的频谱,幅度是随频率的增高而逐渐减小的,小到一定程度就可以忽略不计了。因此,可以说这些频谱被限制在某一频率以下。由原消息转换过来的原始信号所固
First, an overview of the so-called “baseband” is an abbreviation of the basic band. A conversion from the information. The signal generally does not have a strict sine or cosine signal, its frequency content is not a single frequency, but a band. For some voltage or current pulses transmitted in a data communication system, there are some direct current pulses before modulation. The direct current pulse not only contains the direct current component, but also has a lot of alternating current components of different frequencies. These alternating current components have fundamental waves and numerous times harmonic. The frequency and amplitude of these pulses gradually decrease with increasing frequency, to a certain extent negligible. Therefore, it can be said that these spectra are limited to below a certain frequency. The original signal is converted from the original signal is solid