low-pass, high pass, band-pass, band-stop) design. On this basis, the use of virtual realization of analog filters MATLAB. Good scalability of this design, easy to adjust the performance of filters can be based on different requirements to be in the realization of MATLAB.Through the MATLAB simulation and realization of, we can see that the traditional design method of analog filters and do not intuitive red, and MATLAB with more stringent scientific computing and graphical display of the advantages of the design showed that the more intuitive, but also to filter accuracy has been greatly improved to better achieve the desired results. At the same time, low-pass analog filters of high pass, band-pass, band-stop conversion of a theoretical

KEYWORD: Filtering, Analog filters, MATLAB

1 引言 .............................................................................................................................................. 2

2.3.2模拟滤波器滤波器的工作原理 .................................................................................... 8 我们知道，模拟滤波器是对模拟信号实行线性滤波的一种线性时不变系统，如图1.1所示。在时域内，它的动态特性可以用系统的单位冲激函数的响应ha(t)来描述，也就是该滤波系统在任何时刻对输入单位冲激信号xa t =δ（t）的输出响应ya t ha t 。这个函数从时域上反映了该滤波系统的传输特性。对于任意输入信号xa t ，系统的输出ya t 可以卷积表示： ............................................................................................................ 8

2.4 滤波器的基本特性 ....................................................................................................... 10

2.4.1 模拟滤波器与数字滤波器的基本特性 ..................................................................... 10

2.4.2 无限冲击响应IIR和有限冲击响应FIR滤波器 ............................................. 11

2.5 滤波器的主要技术指标 ................................................................................................. 12

1 引言

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