A comparative study of MFSK and CDMA for power line communication with background Nakagami noise

Direct sequence code division multiple access (DS-CDMA) and M-ary frequency shift keying (MFSK) are two viable modulation schemes for broadband power line communication (PLC) channels, for multi-carrier and single carrier cases respectively. In this paper, we study the bit error rate (BER) performance of a synchronous DS-CDMA system and an MFSK system employing coherent detection for a PLC channel. The background noise present in PLC channel is assumed to follow Nakagami-m distribution as suggested by earlier works. Thereafter a comparison is drawn between the two modulation schemes. In order to draw the comparison at an equal level, we analyse the BER performances of the two systems having the same degree of transmitter/ receiver complexity along with the criteria of same bandwidth occupation, same transmission power as well as the same PLC channel characteristics. The study provides an insight as to how a small change in the parameter of a random variable (RV) describing the background power line noise has a marked influence on the BER performances of the two modulation schemes mentioned above. Also from the simulation results obtained it is quite evident that for a single user case, the MFSK system outperforms the DS-CDMA system at similar data rates.