加hanning窗程序.txt

该程序是加上汉宁窗

%加汉宁窗傅立叶变换％
f=50;%f为基频
t1=0.12;%t1为采样时间
n=64; %n为采样点数
m=64; %m为做fft的点数
w=50;
global k;
t=0:t1/n:(t1-t1/n); 
%x=2.55*cos(4.33*2*pi*f*t+pi/3);
% x=1.5+2*sin(100*pi*t+pi/4)+5*sin(300*pi*t+pi/3);
% x=0.87*sin((4.33*2*pi*t*f+pi/4));
%x=2*sin(1.4*2*pi*w*t+pi/10)+0.933*sin(2.6*2*pi*w*t+pi/9)+1.813*sin(3.8*2*pi*w*t+pi/6);
%  x=2*sin(0.4*2*pi*f*t+pi/18)+0.933*sin(2.3*2*pi*f*t+pi/9)+1.813*sin(3.4*2*pi*f*t+pi/6);
%x=1.5*sin(2*2*pi*w*t+pi/10)+1.8*sin(2.22*2*pi*w*t+pi/6)+0.8*sin(2.43*2*pi*w*t+pi/4);
% x=0.65*sin(1*2*pi*w*t+pi/10)+0.9*sin(1.3*2*pi*w*t+pi/9)+0.6*sin(1.5*2*pi*w*t+pi/6);
%x=2.6*sin(2.23*2*pi*w*t+pi/9)+1.75*sin(2.43*2*pi*w*t+pi/6)+2.3*sin(3.05*2*pi*w*t+pi/10);
% x=4.5*exp((9.7*2*pi*w*t+pi/9)*j)+2.5*exp((3.3*2*pi*w*t*+50*pi/180)*j);
%x=2.6*sin(0.5*2*pi*w*t+pi/4)+10.05*sin(1*2*pi*w*t+pi/6)+3.4*sin(1.5*2*pi*w*t+pi/9)+3.15*sin(3*2*pi*w*t)+2.85*sin(5*2*pi*w*t+pi/10)+3.2*sin(9*2*pi*w*t+pi/18);
%x=15*sin(1*2*pi*w*t+pi/6)+1*sin(2.3*2*pi*w*t+pi/4)+8*sin(3.1*2*pi*w*t+pi/3)+1*sin(4*2*pi*w*t+pi/10);
x=10*sin(1.5*2*pi*w*t+pi/6)+1*sin(2*2*pi*w*t+pi/4)+6*sin(2.5*2*pi*w*t+pi/3)+3*sin(3.1*2*pi*f*t+pi/10);
%x=0.68*sin(2*2*pi*w*t+pi/10)+0.9*sin(2.22*2*pi*w*t+pi/9)+0.75*sin(2.43*2*pi*w*t+pi/6);
%x=0.88*sin(2*2*pi*w*t+pi/3)+0.9*sin(19.21*2*pi*w*t+pi/6)+0.75*sin(20.33*2*pi*w*t+pi/9);
% x=0.88*sin(2.2*2*pi*w*t+pi/3)+0.9*sin(20.1*2*pi*w*t+pi/6)+0.75*sin(24*2*pi*w*t+pi/9);
for i=1:n
    w(i)=0.5*(1-cos(2*pi*i/(n+1)));      
end
xx=x.*w;
y=fft(xx,m);
y1=abs(y(1:m/2))*4/n;
y1(1)=y1(1)/2;
%y2=angle(y(1:m/2))*180/pi+90;
k=(0:(m/2-1)).*(n/t1)./(m*f);
%subplot(1,2,1);
stem(k,y1,'.');
%subplot(1,2,2);
%stem(k,y2,'.');