www.pudn.com > bpsk.rar > bpsk.m

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
% Programmed by Oh Joon 
% 
 
%******************** Preparation part ************************************* 
clear all; 
sr=256000.0; % Symbol rate 
ml=1;        % ml:Number of modulation levels (BPSK:ml=1) 
br=sr .* ml; % Bit rate 
nd = 100;   % Number of symbols that simulates in each loop 
IPOINT=8;    % Number of oversamples 
 
%******************* Filter initialization ******************** 
 
irfn=21;     % Number of filter taps           
alfs=0.5;    % Rolloff factor 
[xh] = hrollfcoef(irfn,IPOINT,sr,alfs,1);   %Transmitter filter coefficients   
[xh2] = hrollfcoef(irfn,IPOINT,sr,alfs,0);  %Receiver filter coefficients 
 
%******************** START CALCULATION ********************* 
%nloop=1000;  % Number of simulation loops 
 
nloop=100; 
Eb_N0=0:10; % Eb/No 
 
for i=1:length(Eb_N0) 
%ber = 0; 
noe = 0;    % Number of error data 
nod = 0;    % Number of transmitted data 
%total = 0; 
Eb = Eb_N0; 
for iii=1:nloop 
     
%******************** Data generation ********************************   
 
	data=rand(1,nd)>0.5;  % rand: built in function 
     
%******************** BPSK Modulation ***********************   
 
    data1=data.*2-1; 
	[data2] = oversamp( data1, nd , IPOINT) ; 
	data3 = conv(data2,xh);  % conv: built in function 
      
%****************** Attenuation Calculation ***************** 
	 
    spow=sum(data3.*data3)/nd; 
	attn=0.5*spow*sr/br*10.^(-Eb_N0(i)/10); 
	attn=sqrt(attn); 
    
%********************** Fading channel ********************** 
 
  % Generated data are fed into a fading simulator 
  % In the case of BPSK, only Ich data are fed into fading counter 
  % [ifade,qfade]=sefade(data3,zeros(1,length(data3)),itau,dlvl,th1,n0,itnd1,now1,length(data3),tstp,fd,flat); 
   
  % Updata fading counter 
  %itnd1 = itnd1+ itnd0; 
 
%************ Add White Gaussian Noise (AWGN) *************** 
	 
    inoise=randn(1,length(data3)).*attn;  % randn: built in function 
	data4=data3+inoise; 
	data5=conv(data4,xh2);  % conv: built in function 
 
	sampl=irfn*IPOINT+1; 
	data6 = data5(sampl:8:8*nd+sampl-1); 
     
%******************** BPSK Demodulation ********************* 
 
    demodata=data6 > 0; 
 
%******************** Bit Error Rate (BER) ****************** 
 
    noe2=sum(abs(data-demodata));  % sum: built in function 
	nod2=length(data);  % length: built in function 
	noe=noe+noe2; 
	nod=nod+nod2; 
 
     
    %ber = noe/nod; 
    %total = total+ noe/nod; 
     
     
end % for iii=1:nloop    
    ber(i) = noe/nod; 
    %Avg_BER(i) = total/nloop; 
    %Q function 
    Qx=(1/2)*erfc((10.^(Eb/10))/sqrt(2)); 
 
end % for i=1:20 
%********************** Output result *************************** 
 
%semilogy(Eb_N0,ber); 
figure; 
semilogy(Eb_N0, ber, 'bo-',Eb_N0,Qx,'rx-'); 
xlabel('Eb/No (dB)'); ylabel('BER'); 
title('Performence of BPSK'); 
axis([0 10 1E-4 1]); 
legend('BPSK AWGN (Simulation)','BPSK AWGN (Theory)'); 
grid on; 
 
 
%******************** end of file ***************************