Investigation of Coherent Multicarrier Code Division Multiple Access for Optical Access Networks

Orthogonal frequency division multiplexing (OFDM) has proved to be a promising technique to increase the reach and bit rate both in long-haul communications and in passive optical networks. This paper, for the first time, investigates the use of OFDM combined with electrical CDMA in presence of coherent detection as a multiple access scheme. The proposed multicarrier-CDMA system is simulated synchronously using Walsh-Hadamard codes and its performance is evaluated in terms of bit-error-rate and spectral efficiency. It is shown that the system error slightly increases for greater number of users due to multiple-access interference. BER can be reduced using longer code words for the same number of users at the expense of losing spectral efficiency

Keywords:

Fiber Optic Communication , Optical MC-CDMA , Coherent Detection , Optical Access Network , OptiSystem