《DSP using MATLAB》Problem 5.38


代码:
%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
%% Output Info about this m-file
fprintf('\n***********************************************************\n');
fprintf(' <DSP using MATLAB> Problem 5.38 \n\n'); banner();
%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ % ------------------------------------------------------------------------
% 1 x(n) = [2sin(0.04pi*n)+5cos(0.08pi*n)]
% N=40 N=50 N=60
%
% ------------------------------------------------------------------------
N = 40;
nn1 = [0:N-1];
xx1 = 2*sin(0.04*pi*nn1)+5*cos(0.08*pi*nn1);
NN1 = length(xx1); % length %m = mod_1(nn1, NN1);
%x = [xx1 zeros(1, 0)]; % padding zeros
%n = [nn1 max(nn1)+1:max(nn1)+6];
x = xx1;
n = nn1; str = fprintf('P5.38.1 x(n) N=%d', N);
figure('NumberTitle', 'off', 'Name', str);
set(gcf,'Color','white');
subplot(2,1,1); stem(nn1, xx1);
xlabel('n'); ylabel('x(n)');
title('x(n) ori sequence'); grid on;
subplot(2,1,2); stem(n, x);
xlabel('n'); ylabel('x(n)');
title('x(n) padding 0 zeros'); grid on; %% =============================================================================
%% DTFT X(w) of xn sequence, w=[0:2pi],
%% =============================================================================
MM = 500;
[Xw_DTFT, w] = dtft1(x, n, MM); magXw_DTFT = abs(Xw_DTFT); angXw_DTFT = angle(Xw_DTFT)/pi;
realXw_DTFT = real(Xw_DTFT); imagXw_DTFT = imag(Xw_DTFT); %% --------------------------------------------------------------
%% START X_DTFT's mag ang real imag
%% --------------------------------------------------------------
figure('NumberTitle', 'off', 'Name', 'P5.38.1 X(w) DTFT of x(n) N=40');
set(gcf,'Color','white');
subplot(2,2,1); plot(w/pi,magXw_DTFT); grid on; % axis([-2,2,0,15]);
title('Magnitude Part');
xlabel('frequency in \pi units'); ylabel('Magnitude |X\_DTFT|');
subplot(2,2,3); plot(w/pi, angXw_DTFT); grid on; % axis([-2,2,-1,1]);
title('Angle Part');
xlabel('frequency in \pi units'); ylabel('Rad \pi'); %axis([-200,200,0,2]); subplot('2,2,2'); plot(w/pi, realXw_DTFT); grid on;
title('Real Part');
xlabel('frequency in \pi units'); ylabel('Real');
subplot('2,2,4'); plot(w/pi, imagXw_DTFT); grid on;
title('Imaginary Part');
xlabel('frequency in \pi units'); ylabel('Imaginary');
%% --------------------------------------------------------------
%% END X_DTFT's mag ang real imag
%% -------------------------------------------------------------- %% ------------------------------------------------------------------
%% DFT(k) of xn sequence, k=[0:N-1]
%% w=2pi*k/N k=Nw/(2pi)
%% ------------------------------------------------------------------
N1 = length(x);
k1 = [0 : N1-1];
%k2 = [-N : N-1];
%k3 = [-N/2 : N/2];
Xk_DFT = dft(x, N1); % DFT
magXk_DFT = abs( [ Xk_DFT ] ); % DFT magnitude
angXk_DFT = angle( [Xk_DFT] )/pi; % DFT angle
realXk_DFT = real(Xk_DFT); imagXk_DFT = imag(Xk_DFT); figure('NumberTitle', 'off', 'Name', 'P5.38.1 DFT(k) of x(n) N=40')
set(gcf,'Color','white');
subplot(2,1,1); stem(k1, magXk_DFT); hold on; plot(N1*w/(2*pi), magXw_DTFT,'r--'); hold off;
%axis([-N/2, N/2, -0.5, 50.5]);
xlabel('k'); ylabel('magnitude(k)');
title('DFT magnitude of x(n)'); grid on;
subplot(2,1,2); stem(k1, angXk_DFT); hold on; plot(N1*w/(2*pi), angXw_DTFT,'r--'); hold off;
%axis([-N/2, N/2, -0.5, 50.5]);
xlabel('k'); ylabel('angle(k)');
title('DFT angle of x(n)'); grid on; %% =============================================================================
%% DTFT X(w) of xn sequence, w=[-2pi:2pi],
%% =============================================================================
MM = 500;
[Xw_DTFT, w] = dtft2(x, n, MM); magXw_DTFT = abs(Xw_DTFT); angXw_DTFT = angle(Xw_DTFT)/pi;
realXw_DTFT = real(Xw_DTFT); imagXw_DTFT = imag(Xw_DTFT); %% --------------------------------------------------------------
%% START X_DTFT's mag ang real imag
%% --------------------------------------------------------------
figure('NumberTitle', 'off', 'Name', 'P5.38.1 X(w) DTFT of x(n) N=40');
set(gcf,'Color','white');
subplot(2,2,1); plot(w/pi,magXw_DTFT); grid on; % axis([-2,2,0,15]);
title('Magnitude Part');
xlabel('frequency in \pi units'); ylabel('Magnitude |X\_DTFT|');
subplot(2,2,3); plot(w/pi, angXw_DTFT); grid on; % axis([-2,2,-1,1]);
title('Angle Part');
xlabel('frequency in \pi units'); ylabel('Rad \pi'); %axis([-200,200,0,2]); subplot('2,2,2'); plot(w/pi, realXw_DTFT); grid on;
title('Real Part');
xlabel('frequency in \pi units'); ylabel('Real');
subplot('2,2,4'); plot(w/pi, imagXw_DTFT); grid on;
title('Imaginary Part');
xlabel('frequency in \pi units'); ylabel('Imaginary');
%% --------------------------------------------------------------
%% END X_DTFT's mag ang real imag
%% -------------------------------------------------------------- %% ------------------------------------------------------------------
%% DFT(k) of xn sequence, k=[-N:N-1]
%% w=2pi*k/N k=Nw/(2pi)
%% ------------------------------------------------------------------
N2 = length(x);
%k1 = [0 : length(x)-1];
k2 = [-N2 : N2-1];
%k3 = [-N/2 : N/2];
Xk_DFT = dft(x, N2); % DFT
magXk_DFT = abs( [ Xk_DFT Xk_DFT] ); % DFT magnitude
angXk_DFT = angle( [Xk_DFT Xk_DFT] )/pi; % DFT angle
realXk_DFT = real([Xk_DFT Xk_DFT]);
imagXk_DFT = imag([Xk_DFT Xk_DFT]); figure('NumberTitle', 'off', 'Name', 'P5.38.1 DFT(k) of x(n) N=40')
set(gcf,'Color','white');
subplot(2,1,1); stem(k2, magXk_DFT); hold on; plot(N2*w/(2*pi), magXw_DTFT,'r--'); hold off;
%axis([-N/2, N/2, -0.5, 50.5]);
xlabel('k'); ylabel('magnitude(k)');
title('DFT magnitude of x(n)'); grid on;
subplot(2,1,2); stem(k2, angXk_DFT); hold on; plot(N2*w/(2*pi), angXw_DTFT,'r--'); hold off;
%axis([-N/2, N/2, -0.5, 50.5]);
xlabel('k'); ylabel('angle(k)');
title('DFT angle of x(n)'); grid on; %% =============================================================================
%% DTFT X(w) of xn sequence, w=[-pi:pi],
%% =============================================================================
MM = 500;
[Xw_DTFT, w] = dtft3(x, n, MM); magXw_DTFT = abs(Xw_DTFT); angXw_DTFT = angle(Xw_DTFT)/pi;
realXw_DTFT = real(Xw_DTFT); imagXw_DTFT = imag(Xw_DTFT); %% --------------------------------------------------------------
%% START X_DTFT's mag ang real imag
%% --------------------------------------------------------------
figure('NumberTitle', 'off', 'Name', 'P5.38.1 X(w) DTFT of x(n) N=40');
set(gcf,'Color','white');
subplot(2,2,1); plot(w/pi,magXw_DTFT); grid on; % axis([-2,2,0,15]);
title('Magnitude Part');
xlabel('frequency in \pi units'); ylabel('Magnitude |X\_DTFT|');
subplot(2,2,3); plot(w/pi, angXw_DTFT); grid on; % axis([-2,2,-1,1]);
title('Angle Part');
xlabel('frequency in \pi units'); ylabel('Rad \pi'); %axis([-200,200,0,2]); subplot('2,2,2'); plot(w/pi, realXw_DTFT); grid on;
title('Real Part');
xlabel('frequency in \pi units'); ylabel('Real');
subplot('2,2,4'); plot(w/pi, imagXw_DTFT); grid on;
title('Imaginary Part');
xlabel('frequency in \pi units'); ylabel('Imaginary');
%% --------------------------------------------------------------
%% END X_DTFT's mag ang real imag
%% -------------------------------------------------------------- %% ------------------------------------------------------------------
%% DFT(k) of xn sequence, k=[-N/2:N/2]
%% w=2pi*k/N k=Nw/(2pi)
%% ------------------------------------------------------------------
N3 = length(x);
%k1 = [0 : length(x)-1];
%k2 = [-N : N-1];
k3 = [-N3/2 : N3/2];
Xk_DFT = dft(x, N3); % DFT
magXk_DFT = abs( [ Xk_DFT(N3/2+1 : N3) Xk_DFT(1 : N3/2+1)] ); % DFT magnitude
angXk_DFT = angle( [Xk_DFT(N3/2+1 : N3) Xk_DFT(1 : N3/2+1)] )/pi; % DFT angle
% realXk_DFT = real([Xk_DFT(N/2+1 : N) Xk_DFT(1 : N/2+1)]);
% imagXk_DFT = imag([Xk_DFT(N/2+1 : N) Xk_DFT(1 : N/2+1)]); figure('NumberTitle', 'off', 'Name', 'P5.38.1 DFT(k) of x(n) N=40')
set(gcf,'Color','white');
subplot(2,1,1); stem(k3, magXk_DFT); hold on; plot(N3*w/(2*pi), magXw_DTFT,'r--'); hold off;
%axis([-N/2, N/2, -0.5, 50.5]);
xlabel('k'); ylabel('magnitude(k)');
title('DFT magnitude of x(n)'); grid on;
subplot(2,1,2); stem(k3, angXk_DFT); hold on; plot(N3*w/(2*pi), angXw_DTFT,'r--'); hold off;
%axis([-N/2, N/2, -0.5, 50.5]);
xlabel('k'); ylabel('angle(k)');
title('DFT angle of x(n)'); grid on;
运行结果:





下面是N=50的情况,附图




《DSP using MATLAB》Problem 5.38的更多相关文章
- 《DSP using MATLAB》Problem 8.38
代码: function [wpLP, wsLP, alpha] = bp2lpfre(wpbp, wsbp) % Band-edge frequency conversion from bandpa ...
- 《DSP using MATLAB》Problem 7.38
代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...
- 《DSP using MATLAB》Problem 7.27
代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...
- 《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: %% +++++++++++++++++++++++++++++++++++++ ...
- 《DSP using MATLAB》Problem 7.25
代码: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output In ...
- 《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: %% +++++++++++++++++++++++++++++++++++++++ ...
- 《DSP using MATLAB》Problem 7.23
%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %% Output Info a ...
- 《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: %% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ...
- 《DSP using MATLAB》Problem 7.15
用Kaiser窗方法设计一个台阶状滤波器. 代码: %% +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ ...
随机推荐
- laravel模型表建立外键约束的使用:
模型: //表->posts class Post extends Model { //关联用户: public function user(){ //belongsTo,第一个参数:外键表,第 ...
- mongodb细节
MongoDB中数值型默认为Double,可以使用NumberInt()函数及NumberLong()函数分别指定某个字段为整型和长整型.
- svg 学习笔记
http://git.oschina.net/heboliufengjie/demo/tree/master/svg?dir=1&filepath=svg&oid=3a44203972 ...
- 整数中1出现的次数(1~n)
题目描述 求出1~13的整数中1出现的次数,并算出100~1300的整数中1出现的次数?为此他特别数了一下1~13中包含1的数字有1.10.11.12.13因此共出现6次,但是对于后面问题他就没辙了. ...
- 红黑树与AVL
红黑树和avl树都属于自平衡二叉树: 两者查找.插入.删除的时间复杂度相同: 包含n个内部结点的红黑树的高度是o(logn); TreeMap是一个红黑树的实现,能保证插入的值保证排序 ...
- loj6277
题解: 树状数组模板提 代码: #include<bits/stdc++.h> using namespace std; ; int num[N],n,a[N],l,r,c,opt; vo ...
- java局部变量,成员变量在堆和栈中的存储
对于局部变量,如果是基本类型,会把值直接存储在栈:如果是引用类型,比如String s = new String("william");会把其对象存储在堆,而把这个对象的引用(指针 ...
- [POJ3481]Double Queue
Problem 0 结束操作 1 K P 将一个数K以优先级P加入 2 取出优先级最高的那个数 3 取出优先级最低的那个数 Solution Splay模板题 Notice 是输出数而不是输出优先级. ...
- 【原创】连接数据库MySQL,读取、显示、修改数据
/* Time: 2017.01.02 —— 2017.01.04 * Author: WJ * Function:连接数据库,从数据库中读取图片并显示(已成功) */ [参考链接] MySQL存入图 ...
- day26 第二阶段共享
第二阶段共享--网络编程 一.C/S架构 : 客户端(client)/服务端(sever)框架 B/S架构: 浏览器(brower)/服务端(sever)架构 软件CS架构: 服务端连接到浏览器,QQ ...