High-speed Powerline Communications Technology Research

This thesis is mainly focused on the performance of OFDM and MC-CDMA architectures in the High Speed Power Line Communications. At the first beginning, the Power Line Communications is introduced. Then the noises in the power line channel are analyzed, followed by a study of the OFDM system for its capability to resist the impulsive noise. Simulation results show that for large Signal-to-Noise Ratio (SNR), the OFDM system with large number of carriers can cope with the impulsivity of the noise, even when it is very impulsive, and can improve the performance efficiently. Based on the Frequency Selective Multipath Slow Fading channel model obtained from the physical transmission characteristics of the power line, the channel capacity in the OFDM system is derived to prove the feasibility for high-speed communications in the first place, and after that, the adaptive OFDM and Trellis Coded OFDM are implemented to improve the communication quality. Simulations show that the modified OFDM systems are superior to the fixed OFDM system in the sense of Bit Error Rate (BER) performance. In the last section of this thesis, the BER performance between the MC-CDMA system and the fixed OFDM system are compared and the simulation results show that at high SNR, the former outperforms the latter for the BER criteria and if combined with coding, it is even better because of the additional coding gain obtained.