MR.Ajay Vyas thank u for ur reply.sir we are confusing about FFT size ,position array,number of subcarrier ,cyclic prefix in ofdm modulator block.BY using no.of subcarrier 512,position array 256,FFT size 1024,cyclic prefix 64 we have got the Q-factor 10^49 and min BER is 0.is it correct this is our ques?.And also
1. IN WDM/OFDM PON,we retrieve the downstream at ONU But upstream signal not send after the AWG mux demux block but we have same output at OLT in BER give us some idea sir.if any one know give us some idea.
2.AND also if we are using different wavelength in upstream and downstream ,we have got the result in ONT not get the result at OLT