ds_cdma.m

A DS Spread Spectrum simulation code.

% MATLAB script for DS CDMA simulation
echo on
Lc=20;			  		% Number of chips per bit
A1=3;			  		% amplitude of the first sinusoidal interference
A2=7;			  		% amplitude of the second sinusoidal interference
A3=12;			  		% amplitude of the third sinusoidal interference
A4=0;			  		% fourth case: no interference
w0=1;			  		% frequency of the sinusoidal interference in radians
SNRindB=0:2:30;
for i=1:length(SNRindB),
  % measured error rates
  smld_err_prb1(i)=ss_Pe94(SNRindB(i),Lc,A1,w0);
  smld_err_prb2(i)=ss_Pe94(SNRindB(i),Lc,A2,w0);
  smld_err_prb3(i)=ss_Pe94(SNRindB(i),Lc,A3,w0);
  echo off ;
end;
echo on ;
SNRindB4=0:1:8;
for i=1:length(SNRindB4),
  % measured error rate when there is no interference
  smld_err_prb4(i)=ss_Pe94(SNRindB4(i),Lc,A4,w0); 
  echo off ;
end;    	
echo on ;		          
% Plotting commands follow

figure; semilogy(SNRindB,smld_err_prb1,'b',SNRindB,smld_err_prb2,'g',SNRindB,smld_err_prb3,'c',SNRindB4,smld_err_prb4,'k');
legend('A=3','A=7','A=12','A=0');