%qamdemod2.m
%16QAM解調(diào)程序
function[demodata]=qamdemod2(idata,qdata,para,nd,ml)
%******************variables*************************
%idata:I信道輸入數(shù)據(jù)
%qdata:Q信道輸入數(shù)據(jù)
%demodata:解調(diào)出的數(shù)據(jù)
%para:并行信道數(shù)
%nd:數(shù)據(jù)數(shù)
%ml:調(diào)制數(shù)
%(QPSK->2 16QAM->4)
%*****************************************************
k=sqrt(10);
idata=idata.*k;
qdata=qdata.*k;
demodata=zeros(para,ml*nd);
m2=ml/2;
count2=0;
for ii=1:nd
for kk=1:para
a=1;
b=1;
i_lngth=0;
q_lngth=0;
for jj=1:m2
if jj~=1
if demodata(kk,jj-1+count2)==1
a=-a;
end
if demodata(kk,m2+jj-1+count2)==1
b=-b;
end
i_lngth=i_lngth+i_plrty.*2.^(m2-jj+1);
q_lngth=q_lngth+q_plrty.*2.^(m2-jj+1);
end
if idata(kk,ii)>=i_lngth
demodata(kk,jj+count2)=a>=0;
i_plrty=1;
else
demodata(kk,jj+count2)=a<=0;
i_plrty=-1;
end
if qdata(kk,ii)>=q_lngth
demodata(kk,m2+jj+count2)=b>=0;
q_plrty=1;
else
demodata(kk,m2+jj+count2)=b<=0
q_plrty=-1;
end
end%for jj=1:m2
end%kk=1:para
count2=count2+ml;
end%for ii=1:nd
%********************end of file***************************