passband.m

this code for qpsk with awgn

clear all;clf
samp=32;
data=randint(1,20,2,1)
T=10^-3;
f=1000;
t=0:1/samp:1-(1/samp);
SQ=data;
SI=1-data;
basis1=(sqrt(2/T))*cos(2*pi*f*t);
basis2=(-1)*(sqrt(2/T))*sin(2*pi*f*t);
S1=basis1;
S2=basis2;
qpskI=(S1'*SI);
qpskQ=(S2'*SQ);
qpsk=qpskI+qpskQ;    %%%%%keluaran pemancar
subplot(2,1,1)
plot(t,qpsk)
qpsknoise=awgn(qpsk,0,'measured')    %%%%penambahan noise AWGN (diumpamakan di kanal)
subplot(2,1,2)
plot(t,qpsknoise)
z1=basis1*qpsknoise
z2=basis2*qpsknoise
z=sign(z1-z2)
z=(1-z)/2

%menghitung BER
[N,BER]=biterr(z,data)