run.m

离散多载波传输(DMT)的MATLAB程序及注释

B= 4; % # of bits
C= 16; % # of points in constellation
S= 256; % # samples of handel
L=16; % length of channel
%noise=.00001; % noise amplitude
%sN=0; % # TD spikes
N=16; % length of cyclic pad
F=128; % length of blocks (1/2 # of subchannels) dmt
%F=1; %single carrier
M=constbuilder(C); % constellation matrix

s=abs(randn(L,1));  % random channel
s=s./sum(s);

%file_input_type=1;
data_in=readfile('short.wav');
x=data_in';

% load handel
% y=y(1:S);
% x=a2d(y,B);
z=constmap(x,M);
a=series2parallel(z,F);% dmt
%a=z;%sigle carrier
b=mirror(a);
c=ifft(b); 
d=cyclicpad(c,N);
%e=matlaberr(d);%sigle carrier
e=matlaberr(parallel2series(d));% dmt 

%for SNR=-50:3:80
SNR=52;
aN1= randn(length(conv(e,s)),1);
ps=(norm(e))^2;
pn1=(norm(aN1))^2;
noise=sqrt(ps/pn1)*10.^(-SNR/20);
aN=aN1*noise;

f=channel(e,s,aN);
f=f(1:length(e));
%g=f;%sigle carrier
g=series2parallel(f,2*F+N);% dmt
h=decyclicpad(g,N);
k=fft(h); 
m=filterchannel(k,s);
n=demirror(m);
n(1,:)=a(1,:);
%o=n;%single carrier
o=parallel2series(n);% dmt 
p=approximate(o,M);
q=deconstmap(p,M);
%r=d2a(q,B);

writefile(q);

% x=readfile('txtin.txt');
% q=readfile('dmttxt.txt');
biterr=sum(abs(x-q));
ber=biterr/(length(x));




% % %for original input
% data_samples=wavread('short.wav');
% output_samples=wavread('dmtshort.wav');
% % output_samples1=wavread('scshort.wav');
% % 
% figure(1);
% subplot(3,1,1)
% plot(data_samples(1:1000));
% subplot(3,1,2)
% plot(output_samples(1:1000));
% subplot(3,1,3)
% plot(output_samples1(1:1000));