lms.rar_LMS系统辨识_系统辨识lms

n=4; N=500; delta=0.8; X1=1;X2=0;X3=1;X4=0; %移位寄存器输入Xi初T态（0101）， Yi为移位寄存器各级输出 m=500; %置M序列总长度 for i=1:m %1# Y4=X4; Y3=X3; Y2=X2; Y1=X1; X4=Y3; X3=Y2; X2=Y1; X1=xor(Y3,Y4); %异或运算 if Y4==0 U(i)=-1; else U(i)=Y4; end end u=U; z=zeros(1,500); %定义输出观测值的长度 for k=3:500 z(k)=1.5*z(k-1)-0.7*z(k-2)+u(k-1)+0.5*u(k-2); %用理想输出值作为观测值 end h = zeros(N+1,n); e(n)=0; for i=n+1:N y(i)=0; for j=1:n y(i)=y(i)+h(i,j).*u(i-j+1); tr=norm(u((i-n):i))^2; h(i+1,j)=h(i,j)+delta*e(i-1)*u(i-j+1)/tr; end e(i)=z(1,i)-y(i); end figure(1) plot(0:N-n,u(n:N)),grid title('x(k) input signal in V ') xlabel('simples') figure(2) plot(0:N-n,z(1,n:N),'r'),hold on %plot(0:N-n,e(n:N),'g'),hold on %plot(0:N-n,h(n:N,1),'b'),hold off grid title('e(k) error and y(k) output in V') xlabel('samples')