clear
clc
c=6;         % 子載波個數(shù)
bits=4000;      % 每個信道的比特數(shù)
n=c*bits;       % 總的傳送比特數(shù)
data= 2*round(rand(1,n))-1;     %產(chǎn)生信源數(shù)據(jù)
s = reshape(data,c,bits);        % 串并變換
tp=1:0.1:(1+bits/10)-0.1;
for i=1:c
    carrier(i,:)=cos(2*i*pi*tp); % 產(chǎn)生載波信號
    bpsk_sig(i,:)=s(i,:).*carrier(i,:); % 產(chǎn)生調制信號
    fin(i,:)=ifft(bpsk_sig(i,:));  %對信號進行ifft
end
%并串變換
transmit=reshape(fin,1,n);
%加噪聲
snr=[-5:2:16];
for t=1:length(snr)
    rxdata=awgn(transmit,snr(t),'measured');
    %并串變換
    rec=reshape(rxdata,c,bits);
    for i=1:c
        rxdataf(i,:)=fft(rec(i,:));  %進行FFT處理
        uncarry(i,:)=rxdataf(i,:).*carrier(i,:); %解調
    end
    rdata=sign(real(uncarry));
    num(t)=biterr(rdata+1,s+1)/n;
end