errprob.m

In 揚erformance of multi-carrier DS CDMA Systems?we apply a multi-carrier signaling technique to a di

function [err avp n1] = errprob(data,snr_in_dB,M,pn,h)
% ----------------------------------------------------------------------- %
global err
snr = 10^(snr_in_dB/10);;
Nusers = 3;
N = 100;
Nc = 31; 
T = 1;
Tc = (T/Nc);
%chip duration of MC-DS-CDMA
Nsample = 1; ts = Tc/Nsample; 
fs = 1/ts; 
%To save run time, we can select fc to be [1:M]*10000;
%To ensure that bandwidth of subcarrier doesn't overlap each other. 
for i = 1:M
    fc(i) = 10000+(1/(2*Tc));
end;
error = 0; 
iteration = 2;
for n = 1:iteration        
    for i = 1:N, 
        %Sampling time
        t = [(i-1)*T:ts:i*T-ts]; 
        datat = data(i,:);         
        %Transmitter
        trans = transmitter(datat,t,Nsample,Nc,pn,M,fc,Nusers); 
        E = sum(trans.^2); 
        simga = sqrt(E/snr);
        
        %For multicarrier system 
        hno=(randn(1,Nc)+j*randn(1,Nc));
         for path = 1:M            
            noise = simga*hno; 
            rec(path,:) = conv(h(path),trans)+noise; 
        end; 
        %Receiver
        z = multirece(rec,h,t,Nsample,Nc,pn,M,fc,Nusers); 
        %decision 
        if z(1)<1 
            decision = 0;
        else
            decision = 1;
        end; 
        if decision ~= datat(1) 
            error = error+1;
        end;
    end; 
    p(n) = error/(Nusers*N);    
end; 
avp = sum(p(n))/iteration;
% ----------------------------------------------------------------------- %