GMSK detector code help

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lincolndsp

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mlse equalizer

Guys, could anyone send me the Matlab code
for GMSK MLSE detector with Viterbi equalizer and/or
GMSK coherent detector with no Viterbi.
 

gmsk coherent detector

YOU MAY REFER THIS SIMULATION POSTED ON FOLLOWING LINK.
 

    lincolndsp

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Re: BPSK simulation BER

QPSK Simulation with soft-output demodulator


function y=mod_qpsk(x)
NN=size(x,1);
N=size(x,2)/2;
r=1;
for nn=1:NN
for n=1:N
if x(nn,2*n-1)==0&x(nn,2*n)==0;
y(nn,n)=r*exp(j*pi/4);
elseif x(nn,2*n-1)==0&x(nn,2*n)==1;
y(nn,n)=r*exp(j*pi*3/4);
elseif x(nn,2*n-1)==1&x(nn,2*n)==1;
y(nn,n)=r*exp(j*pi*5/4);
elseif x(nn,2*n-1)==1&x(nn,2*n)==0;
y(nn,n)=r*exp(j*pi*7/4);
else
error('qpsk input error');
end
end
end


function y=soft_qpsk_demod(x)
%x=[-0.3162-0.3162*j];
NN=size(x,1);
N=size(x,2);
r=1;
x=x/r;

con=exp(j*pi*(1:2:7)/4);
out=[0 1 3 2];
for nn=1:NN
for n=1:N
i=1;
while (i<=4)&(x(nn,n)~=con(i))
d(i)=1/abs(x(nn,n)-con(i));
%ed(1:2,i)=d(i)*(ones(1,2)-2*deci2bin(out(i),2))';
ed(1:2,i)=d(i)*(deci2bin(out(i),2))';
i=i+1;
end
if i==5
y(nn,2*n-1:2*n)=sum(ed')/sum(d);
else
%y(nn,2*n-1:2*n)=(ones(1,2)-2*deci2bin(out(i),2));
y(nn,2*n-1:2*n)=(deci2bin(out(i),2));
end
end
end
 
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    lincolndsp

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    RIA007

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The attached files contain the Simulation programs of GSM which use the GMSK modem. I hope they are useful.
 
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