dsp1_2.m

实现补长可变的LMS程序

%  姓名:齐家红 学号：200520203020
clc
clear
%2.1
a1=-0.195;a2=0.95;
c=(1-a2)*((1+a2)^2-(a1)^2)/(1+a2);
v=randn(1000,1)*c^0.5;
for m=3:1:1002
    u(2)=0;
    u(1)=0;
    u(m)=-a1*u(m-1)-a2*u(m-2)+v(m-2);
end
u;
%  2.2
r1=0;
r=zeros(1,1000);
for l=2:1:1000
    for k=(l+2):1:1002
        r1=(u(k)*conj(u(k-l+1))+r1);
    end
    r(l)=r1/1000;
    r1=0;
end
r12=0;
for k1=3:1:1002
    r12=(r12+u(k1)^2);
end
r(1)=r12/1000;
r;
%2.3
a11=-r(2)*(r(1)-r(3))/(r(1)^2-r(2)^2)
a21=(-r(1)*r(3)-r(2)^2)/(r(1)^2-r(2)^2)
c1=r(1)+a11*r(2)+a21*r(3)
a1
a2
c
%2.4
w=0:pi/1000:2*pi;
r1=zeros(255,1);
for m1=1:255
    r1(m1)=double(r(257-m1));
end
pt1=0.0000000;
pt2=0.0000000;
pt=0.00000000;
for k1=2:1:256
  pt1=pt1+r(k1)*exp(-i*w*k1);
end
pt1;
for l2=1:1:255
    pt2=pt2+r1(l2)*exp(i*w*257-l2);
end
pt2;
pt=pt1+pt2+1;
subplot(2,1,1);
plot(w,pt);
title('DSP作业第一次图(3)  姓名:齐家红 学号：200520203020');
Hw2=1./(1+a11*exp(-i*w)+a21*exp(-i*2*w));
Pw2=c1.*abs(Hw2).^2;
Pw2;
subplot(2,1,2);
plot(w,Pw2);