BPSK Demodulation code

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Calvert

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Please help me about BPSK demodulation code. I have face many problems at working time. If problems are incurred during working the speed of output is very slow.
physical therapy billing coding
 
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Did you get anything Calvert? I am also looking for the same.
 

Hi. I have the same problem. I am trying to demodulate BPSK signal and here is my way: BPSK signal .* carrier => integral => compare with 0 (if >0 is 1 and <0 is -1)=> recover original signal.
Use can follow this link: **broken link removed** but if we use LPF, the BER is really high. My teacher said "use integral and then compare to 0". But now I have problem with integral signal because BPSK signal is not defined function (if you want to use integral function in matlab you should define function)
Any one help?
 

Here is all you need. It's part of my Project.
Hope this help
Code:
clc
clear all
close all

% Generation of bit pattern
s=round(rand(1,25));    % Generating 25 bits
signal=[];  
carrier=[];
t=[0:2*pi/119:2*pi];     % Creating 60 samples for one cosine 
for k=1:25
    if s(1,k)==0
        sig=-ones(1,120);    % 120 minus ones for bit 0
    else
        sig=ones(1,120);     % 120 ones for bit 1
    end
    c=cos(t);   
    carrier=[carrier c];
    signal=[signal sig];
end
figure(1)
subplot(6,1,1);
plot(signal);
axis([-100 3100 -1.5 1.5]);
title('\bf\it Original Bit Sequence');

subplot(6,1,2);
plot(carrier);
axis([-100 3100 -1.5 1.5]);
title('\bf\it Original Bit Sequence');

% BPSK Modulation of the signal
bpsk_sig=signal.*carrier;   % Modulating the signal
subplot(6,1,3);
plot(bpsk_sig);
axis([-100 3100 -1.5 1.5]);
title('\bf\it BPSK Modulated Signal');


%Demodulation
debpsk_sig=bpsk_sig.*carrier; %Coherent Multiplication
subplot (6,1,4);
plot(debpsk_sig);
axis([-100 3100 -2.5 2.5]);
title('\bf\it After Coherent Multiplication');

y=intdump(debpsk_sig,120); %Integral with period reset
subplot(6,1,5);
plot(y);
title('\bf\it After Intergrated with Period Reset');
orig_sig=[];
%Comparator with threshold 0
for i=1:25
    if y(i)<0
        r_sig=-ones(1,120);    % 120 minus ones for bit 0
    else
        r_sig=ones(1,120);     % 120 ones for bit 1
    end
    orig_sig=[orig_sig r_sig];
end
subplot(6,1,6);
plot(orig_sig);
axis([-100 3100 -1.5 1.5]);
title('\bf\it Original Signal');
 

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