I "improved ?" my programm a little bit:
function out = smallofdm
modulated = pskmod(data)
receivedmodulated1 = fft(OFDMmodulated, 2*k)
receivedmodulated = [receivedmodulated1(1:k)]
if receivedmodulated == modulated
and now it seems it is almost good. But I am still confused.
my questions are now:
1) why I need to do fft 2*k points for the vector of the length k ? is it something with a Nyquist frequency ?
2) why i got 'not succeed' message, when the vectors seems to be equal... ? I saw while displaying vectors are like:
Columns 1 through 7
0 - 1.0000i -0.0000 - 1.0000i 1.0000 - 0.0000i -0.0000 + 1.0000i 1.0000 0.0000 + 1.0000i 1.0000 + 0.0000i
1.0000 - 0.0000i
How to make value like -0.000i or other values close to zero just not important ? I can imagine it is something with round-off values by PC, but how to workaround it in my code ?
thank you for the help