Dissertation (MSc Telecommunications Engineering)In Power line communication the information are sent via electrical power lines. The power lines are characterized by multipath fading and frequency selectivity due to impedance mismatch of the channel and impulsive noise. Therefore there should be a way to increase performance of the system. In this dissertation OFDM and MCSS modulation techniques were used to enhance PLC system performance. Bit Error Rate (BER) performance of OFDM and MCSS was analyzed and system efficiency was enhanced by the application of coding techniques. The performance of these modulation techniques were also analyzed with different loads’ impedances. The performance of the system was assessed by the commonly used Bit Error Rate against Signal to Noise Ratio (SNR) diagrams and the comparison of OFDM and MCSS systems was assessed by using the frequency response obtained from the PLC multipath channel model for different number of paths. For both coded and uncoded systems it was observed that at low load impedances the performance of MCSS was much better at higher signal to noise ratio than that of OFDM by a gain of 4dB. But at lower SNR OFDM had a better BER performance compared to MCSS. Additionally in the case of high load impedances the performance of OFDM was better than that of MCSS for systems with a gain of 12dB.