代码:

%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
%% Output Info about this m-file
fprintf('\n***********************************************************\n');
fprintf(' <DSP using MATLAB> Problem 7.9 \n\n'); banner();
%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ws1 = 0.2*pi; wp1 = 0.35*pi; wp2 = 0.55*pi; ws2 = 0.75*pi; As = 40;
tr_width = min((wp1-ws1), (ws2-wp2));
M = ceil(6.2*pi/tr_width) + 1; % Hann Window
fprintf('\nFilter Length is %d.\n', M); n = [0:1:M-1]; wc1 = (ws1+wp1)/2; wc2 = (wp2+ws2)/2; %wc = (ws + wp)/2, % ideal LPF cutoff frequency hd = ideal_lp(wc2, M) - ideal_lp(wc1, M);
w_han = (hann(M))'; h = hd .* w_han;
[db, mag, pha, grd, w] = freqz_m(h, [1]); delta_w = 2*pi/1000;
[Hr,ww,P,L] = ampl_res(h); Rp = -(min(db(wp1/delta_w+1 : 1 : wp2/delta_w))); % Actual Passband Ripple
fprintf('\nActual Passband Ripple is %.4f dB.\n', Rp); As = -round(max(db(ws2/delta_w+1 : 1 : 501))); % Min Stopband attenuation
fprintf('\nMin Stopband attenuation is %.4f dB.\n', As); [delta1, delta2] = db2delta(Rp, As) %Plot figure('NumberTitle', 'off', 'Name', 'Problem 7.9 ideal_lp Method')
set(gcf,'Color','white'); subplot(2,2,1); stem(n, hd); axis([0 M-1 -0.4 0.5]); grid on;
xlabel('n'); ylabel('hd(n)'); title('Ideal Impulse Response'); subplot(2,2,2); stem(n, w_han); axis([0 M-1 0 1.1]); grid on;
xlabel('n'); ylabel('w(n)'); title('Hanning Window'); subplot(2,2,3); stem(n, h); axis([0 M-1 -0.4 0.5]); grid on;
xlabel('n'); ylabel('h(n)'); title('Actual Impulse Response'); subplot(2,2,4); plot(w/pi, db); axis([0 1 -150 10]); grid on;
set(gca,'YTickMode','manual','YTick',[-90,-45,0]);
set(gca,'YTickLabelMode','manual','YTickLabel',['90';'45';' 0']);
set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1]);
xlabel('frequency in \pi units'); ylabel('Decibels'); title('Magnitude Response in dB'); figure('NumberTitle', 'off', 'Name', 'Problem 7.9 h(n) ideal_lp Method')
set(gcf,'Color','white'); subplot(2,2,1); plot(w/pi, db); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Decibels'); title('Magnitude Response in dB');
set(gca,'YTickMode','manual','YTick',[-90,-45,0])
set(gca,'YTickLabelMode','manual','YTickLabel',['90';'45';' 0']);
set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1,1.2,1.55,2]); subplot(2,2,3); plot(w/pi, mag); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Absolute'); title('Magnitude Response in absolute');
set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1,1.2,1.55,2]);
set(gca,'YTickMode','manual','YTick',[0.0,0.5,1.0]) subplot(2,2,2); plot(w/pi, pha); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Rad'); title('Phase Response in Radians');
subplot(2,2,4); plot(w/pi, grd*pi/180); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Rad'); title('Group Delay'); figure('NumberTitle', 'off', 'Name', 'Problem 7.9 h(n)')
set(gcf,'Color','white'); plot(ww/pi, Hr); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Hr'); title('Amplitude Response');
set(gca,'YTickMode','manual','YTick',[-delta2,0,delta2,1 - delta1,1, 1 + delta1])
%set(gca,'YTickLabelMode','manual','YTickLabel',['90';'45';' 0']);
%set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1,1.2,1.55,2]); h_check = fir1(M-1, [wc1 wc2]/pi, 'bandpass', window(@hann,M));
[db, mag, pha, grd, w] = freqz_m(h_check, [1]);
[Hr,ww,P,L] = ampl_res(h_check); figure('NumberTitle', 'off', 'Name', 'Problem 7.9 fir1 Method')
set(gcf,'Color','white'); subplot(2,2,1); stem(n, hd); axis([0 M-1 -0.4 0.5]); grid on;
xlabel('n'); ylabel('hd(n)'); title('Ideal Impulse Response'); subplot(2,2,2); stem(n, w_han); axis([0 M-1 0 1.1]); grid on;
xlabel('n'); ylabel('w(n)'); title('Hanning Window'); subplot(2,2,3); stem(n, h_check); axis([0 M-1 -0.4 0.5]); grid on;
xlabel('n'); ylabel('h\_check(n)'); title('Actual Impulse Response'); subplot(2,2,4); plot(w/pi, db); axis([0 1 -150 10]); grid on;
set(gca,'YTickMode','manual','YTick',[-90,-45,0])
set(gca,'YTickLabelMode','manual','YTickLabel',['90';'45';' 0']);
set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1]);
xlabel('frequency in \pi units'); ylabel('Decibels'); title('Magnitude Response in dB'); figure('NumberTitle', 'off', 'Name', 'Problem 7.9 h(n) fir1 Method')
set(gcf,'Color','white'); subplot(2,2,1); plot(w/pi, db); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Decibels'); title('Magnitude Response in dB');
set(gca,'YTickMode','manual','YTick',[-90,-45,0])
set(gca,'YTickLabelMode','manual','YTickLabel',['90';'45';' 0']);
set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1,1.2,1.55,2]); subplot(2,2,3); plot(w/pi, mag); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Absolute'); title('Magnitude Response in absolute');
set(gca,'XTickMode','manual','XTick',[0,0.2,0.35,0.55,0.75,1,1.2,1.55,2]);
set(gca,'YTickMode','manual','YTick',[0.0,0.5,1.0]) subplot(2,2,2); plot(w/pi, pha); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Rad'); title('Phase Response in Radians');
subplot(2,2,4); plot(w/pi, grd*pi/180); grid on; %axis([0 1 -100 10]);
xlabel('frequency in \pi units'); ylabel('Rad'); title('Group Delay');

  运行结果:

45dB满足设计要求。

理想低通方法加窗截断,获得脉冲响应。其幅度响应(dB和Absolute单位)、相位响应、群延迟

振幅响应,通带部分(放大图)

振幅响应,阻带部分(放大图)

使用fir1函数获得脉冲响应,其幅度响应(dB和Absolute单位)、相位响应、群延迟响应

《DSP using MATLAB》Problem 7.9的更多相关文章

  1. 《DSP using MATLAB》Problem 7.27

    代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...

  2. 《DSP using MATLAB》Problem 7.26

    注意:高通的线性相位FIR滤波器,不能是第2类,所以其长度必须为奇数.这里取M=31,过渡带里采样值抄书上的. 代码: %% +++++++++++++++++++++++++++++++++++++ ...

  3. 《DSP using MATLAB》Problem 7.25

    代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...

  4. 《DSP using MATLAB》Problem 7.24

    又到清明时节,…… 注意:带阻滤波器不能用第2类线性相位滤波器实现,我们采用第1类,长度为基数,选M=61 代码: %% +++++++++++++++++++++++++++++++++++++++ ...

  5. 《DSP using MATLAB》Problem 7.23

    %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output Info a ...

  6. 《DSP using MATLAB》Problem 7.16

    使用一种固定窗函数法设计带通滤波器. 代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ...

  7. 《DSP using MATLAB》Problem 7.15

    用Kaiser窗方法设计一个台阶状滤波器. 代码: %% +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ...

  8. 《DSP using MATLAB》Problem 7.14

    代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...

  9. 《DSP using MATLAB》Problem 7.13

    代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...

  10. 《DSP using MATLAB》Problem 7.12

    阻带衰减50dB,我们选Hamming窗 代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ...

随机推荐

  1. Unity3D_UGUI判断鼠标或者手指是否点击在UI上

    比如战斗场景,UI和3D场景同时都需要响应触摸事件,如果同时响应可能就会出现触摸UI的时候影响到了3D部分.为了解决这个问题在判断3D响应之前要先判断手指是否点击在UI上. 以前NGUI的时候都是自己 ...

  2. 使用Flask部署机器学习模型

    Introduction A lot of Machine Learning (ML) projects, amateur and professional, start with an aplomb ...

  3. 5th,Python购物车模拟

    1.启动程序后,输入用户名密码后,如果是第一次登录,让用户输入工资,然后打印商品列表 2.允许用户根据商品编号购买商品 3.用户选择商品后,检测余额是否够,够就直接扣款,不够就提醒 4.可随时退出,退 ...

  4. js同步、异步、回调的执行顺序以及闭包的理解

    首先,记住同步第一.异步第二.回调最末的口诀 公式表达:同步=>异步=>回调 看一道经典的面试题: for (var i = 0; i < 5; i++) { setTimeout( ...

  5. MySQL5.5安装教程

                                          登录MySQL:mysql -uroot -p密码 退出MySQL:exit | quit 查看数据库:show datab ...

  6. 弹性盒式布局flexbox(dispaly:flex)

    display:flex flex-direction: row(行)/column(列)/row-reverse/column-reverse反方向  //布局 justify-content: s ...

  7. vue中关于v-for性能优化---track-by属性

    vue中关于v-for性能优化---track-by属性 最近看了一些react,angular,Vue三者的对比文章,对比来说Vue比较突出的是轻量级与易上手. 对比Vue与angular,Vue有 ...

  8. Eclipse+Maven+Scala Project+Spark | 编译并打包wordcount程序

    学习用Eclipse+Maven来构建并打包一个简单的单词统计的例程. 本项目源码已托管于Github –>[Spark-wordcount] 第一步 在EclipseIDE中安装Scala插件 ...

  9. ID基本操作(复制页面)(移动页面)(调整跨页页数)(版面调整)5.16

    1.在页面面板中选择要复制的页面.拖动到新建页面图标上就可以新建页面. 2.在页面面板中选择要复制的页面.点击右上角的下箭头选择直接复制跨页. 3.在页面面板中选择要移动的页面.用鼠标拖到要移动的地方 ...

  10. CSS 选择器 选择 拥有多个类名 的元素

    今天开发的时候,碰到这个连起来的类名. 才想起来,这个类似于 <div class="node hide"></div> 连起来写,表示找到  拥有这两个类 ...