如何在矩形块中构建具有标记截止频率的巴特沃斯滤波器，切比雪夫和椭圆滤波器的幅频特性？
以前在这个级别上无法在 LateX / TikZ / PGF 中工作。
我请求合格的帮助。
我需要这个草图 https://www.eg.bucknell.edu/~kozick/ili/img1.gif
在块低通滤波器中我需要描述： https://dspguru.com/img/fig_f3.gif
https://en.wikipedia.org/wiki/Butterworth_filter
https://en.wikipedia.org/wiki/Chebyshev_filter
https://en.wikipedia.org/wiki/Elliptic_filter
我的尝试没有成功。我甚至不知道从哪里开始。
\documentclass[a4paper,border=1mm]{standalone}
\usepackage{tikz}
\usepackage{amsmath}
\newcommand{\Cross}{\mathbin{\tikz [x=1.4ex,y=1.4ex,line width=.2ex] \draw (0,0) -- (2,2) (0,2) -- (2,0);}}%
\usetikzlibrary{positioning}
\usetikzlibrary{positioning,arrows}
\usetikzlibrary{shapes,arrows}
\usetikzlibrary{arrows.meta,positioning}
\begin{document}
\tikzset{%
block/.style={draw, fill=white, rectangle, minimum height=2em, minimum width=3em},input/.style={inner sep=0pt},
output/.style={inner sep=0pt},
sum/.style = {draw, fill=white, circle, minimum size=2mm, node distance=1.5cm, inner sep=0pt},
pinstyle/.style = {pin edge={to-,thin,black}}}
\tikzset{
%---------------------------------------------------------------%
% for use this \tikzset yiu need to load in the preamble %
% the folowing tikz libraries: %
% arrows.meta, calc, chains, positioning and quotes %
%---------------------------------------------------------------%
alias path picture bounding box/.code=%
\pgfnodealias{#1}{path picture bounding box},
CNTRL/.style =
{
> = Triangle,
shorten <>/.style = {shorten <=##1, shorten >=##1},
block/.style = {rectangle, draw, fill=##1,
minimum height=8mm, minimum width=16mm,
outer sep = 0mm},
dot/.style = {fill=##1,
circle, inner sep=0mm, outer sep=0mm, minimum size=1mm,
node contents={}},
%
mlt/.style = {fill=##1,
rectangle, draw=black, minimum size=6mm,
path picture={%
\tikzset{alias path picture bounding box=@}
\draw[very thick,shorten <>=1.5mm,-]
(@.north west) edge (@.south east)
(@.south west) -- (@.north east);
},% end of node contents
node contents={}},
%
sum/.style = {fill=##1,
circle, draw=black, minimum size=6mm,
path picture={%
\tikzset{alias path picture bounding box=@}
\draw[very thick,shorten <>=1mm,-]
(@.north) edge (@.south)
(@.west) -- (@.east);
},% end of node contents
node contents={}},
% default styles settings:
block/.default = cyan!30,
dot/.default = black,
mlt/.default = cyan!30,
sum/.default = cyan!30,
}% end of CNTRL style
}% end of tikzset
\tikzstyle{branch} = [circle,inner sep=0pt,minimum size=0.5mm,fill=black,draw=black]
\begin{tikzpicture}[auto, node distance=3cm, on grid, >=latex']
% Place nodes
\node[block,minimum height=2.8cm] (xi) {
\begin{pmatrix}
$\xi(\theta,\gamma,\Theta,\Gamma)$ \\
$I_{ph}(\xi,G_{exH},G_{0})$ \\
$P(I_{ph},V,R_{s},R_{sh})$
\end{pmatrix}};
% input half boxes
\node (n1a) [block,left = of xi] {$\frac{1}{s+1}$};
\node (n1b) [block,above = 1cm of n1a] {$\frac{1}{s+1}$};
\node (n1b) [block,below = 1cm of n1a] {$\frac{1}{s+1}$};
\node [block,below = 2 cm of xi] (i1) {$I_{1}(s)$};
\node [block,below = 1 cm of i1] (i2) {$I_{2}(s)$};
\node [block,below = 1 cm of i2] (i3) {$I_{3}(s)$};
\node [block, right = 4.8cm of i1,minimum width=0.707cm] (prod1) {$\Cross$};
\node [block, right =4cm of i2,minimum width=0.707cm] (prod2) {$\Cross$};
\node [block, right = 3.2cm of i3,minimum width=0.707cm] (prod3) {$\Cross$};
\node [circle,draw=black,left =1.2cm of i1] (sum1) {$+$};
\node [circle,draw=black,left =2cm of i2] (sum2) {$+$};
\node [circle,draw=black,left =2.8cm of i3] (sum3) {$+$};
\node [block, right = 1.5cm of i1,minimum width=0.707cm] (LPF1) {$LPF1$};
\node [block, right =1.5cm of i2,minimum width=0.707cm] (LPF2) {$LPF2$};
\node [block, right = 1.5cm of i3,minimum width=0.707cm] (LPF3) {$LPF3$};
;
\end{tikzpicture}
\end{document}