lmsmmse.m

lms算法 数字信号处理中用到的 希望大家用到

clc
fbconnection=[0 1 0 0 1]; 
mseq=m_sequence(fbconnection); 
fbconnection1=[0 0 1 0 1];
fbconnection2=[0 1 1 1 1]; 
goldseq=gold_seq(fbconnection1,fbconnection2); 
N=2^length(fbconnection)-1; 
ind1=find(mseq==0);
mseq(ind1)=-1;
ind2=find(goldseq==0);
goldseq(ind2)=-1;

bit_number=10000; 
K=16;
data=zeros(K,bit_number);
for i=1:K
    data(i,:)=randsrc(1,bit_number);
end
r=zeros(N,bit_number);
rideal=zeros(N,bit_number);
r1=zeros(N,bit_number);
SNR=-30;
for k=1:K 
    r1=goldseq(k,:)'*data(k,:);
    rideal=rideal+r1;
    r1=awgn(r1,SNR);
    r=r+r1;
end

%lms 算法
userk=10;
lmsN=bit_number;
inp=goldseq(userk,:)*r;
max_inp=max(inp);
inp=inp/max_inp;
d=data(userk,:);
[dtemp,totallength]=size(d);

lmsN=60;
w=zeros(userk,1);
for n=1:lmsN
    u=inp(n)*ones(userk,1);%u=inp(n:-1:n-userk+1);
    y(n)=w'*u;%y(n)=u*w;
    e(n)=d(n)-y(n);
    if n<20
        mu=0.32;
    else
        mu=0.15;
    end
    w=w+mu*u*e(n);%w=w+mu*u'*e(n);
end
for n=lmsN+1:totallength
    u=inp(n)*ones(userk,1); %u=inp(n:-1:n-userk+1);
    y(n)=w'*u; % y(n)=u*w;
    e(n)=d(n)-y(n);
end

tright=0;
newy=sign(y);  %最后输出数据
for lmsi=2:bit_number
    if newy(lmsi)==d(lmsi)
        tright=1+tright; %与原始数据对比,正确的个数
    end
end

trightf=0;
newinp=sign(inp);  %非多用户,最后输出数据
for lmsi=2:bit_number
    if newinp(lmsi)==d(lmsi)
        trightf=1+trightf; %与原始数据对比,正确的个数
    end
end

checkr=[newy;d];

hold on
plot(d)
plot(y,'r');
title('System output') ;
xlabel('Samples')
ylabel('True and estimated output')
figure
semilogy((abs(e))) ;
title('Error curve') ;
xlabel('Samples')
ylabel('Error value')