dspex1.m

滤波器阶数固定时,代价函数和信噪比之间的关系 信噪比固定时,代价函数和滤波器长度之间的关系

% DSP Experiment 3.2.1 Varying Eigenvalues Spread
a1=[-0.195,-0.9750,-1.5955,-1.9114]
a2=[0.95,0.95,0.95,0.95]
r1=[1.1,1.5,1.818,1.957]
r2=[0.9,0.5,0.182,0.0198]
x=[1.22,3,10,100]
Jmin=[0.0965,0.0731,0.0322,0.0038]
v1=zeros(200,4)
v2=zeros(200,4)
w1=zeros(200,4)
w2=zeros(200,4)
v1(1,:)=-0.7072*(a1+a2)
v2(1,:)=-0.7072*(a1-a2)
w1(1,:)=-0
w2(1,:)=-0
J(1,:)=r1.*v1(1,:).^2+r2.*v2(1,:).^2+Jmin
for k=2:200
        v1(k,:)=((1-0.3*r1).^k).*(v1(1,:))
        v2(k,:)=((1-0.3*r2).^k).*(v2(1,:))
        w1(k,:)=-a1-0.7072*(v1(k,:)+v2(k,:))
        w2(k,:)=-a2-0.7072*(v1(k,:)-v2(k,:))
        J(k,:)=r1.*v1(k,:).^2+r2.*v2(k,:).^2+Jmin
end
for k=1:4
    figure(k)
    %subplot(2,2,k)
    plot(v1(:,k),v2(:,k),':b.')
    % axis([-6,6,-6,6])
    axis equal
    grid on
    hold on
    figure(k+4)
    %subplot(2,2,k)
    plot(w1(:,k),w2(:,k),':b.')
   % axis([-6,6,-6,6])
    axis equal
    grid on
    hold on  
end
theta=0:0.01:2*pi
for k=1:4
    for m=1:5
        figure(k)
        x1=((J(m,k)-Jmin(k))/r1(k))^0.5*cos(theta)
        y1=((J(m,k)-Jmin(k))/r2(k))^0.5*sin(theta)
        plot(x1,y1,'-r')
        figure(k+4)
        x2=-a1(k)-0.7072*(x1+y1)
        y2=-a2(k)-0.7072*(x1-y1)
        plot(x2,y2,'-r')
    end    
end

figure(30)
x=1:200
plot(x,J(:,1),'-') 
hold on
plot(x,J(:,2),':') 
hold on
plot(x,J(:,3),'-.') 
hold on
plot(x,J(:,4),'--') 
hold on
axis([0,200,0,1])
grid on