Hi Damian,
Thanks for your kind reply.
I have managed to solve the problem but I think there is still some Error in my code. I am checking the BER for OFDM without using any optical channel. The BER shows 0 which is expected. But when I use optical channel, the BER still shows 0.
Please could you kindly take a look at my Matlab code? Thanks.
Regards,
Rizbi