Broadband data transfer and narrow band transmission, including internet, picture, and video delivery, are currently possible via Power Line Communication (PLC). It is crucial to raise the quality of wide transmission across PLC channel, and this is a current research focus. However, Power lines are not suitable for high-speed data transfer since they are intended to transport electric power at low frequency. The main difficulties in PLC system are multipath effect, inter-symbol interference, frequency selective fading and noise. Orthogonal Frequency Division Multiplexing (OFDM) is a technique frequently employed in PLC to mitigate the impact of multipath fading effect, Additive White Gaussian Noise (AWGN) and Impulsive Noise (IN). The use of OFDM to decrease noise impacts is only effective at low levels of noise energy over PLC system. So, additional noise mitigating measures are required at larger levels of noise energy. In this research work, Low Density Parity Check (LDPC) code and Deep Clipping (DC) nonlinear preprocessing are jointly proposed to mitigate the impact of noise in OFDM based PLC systems. DC preprocessor provides benefits of clipping and nulling the noise of PLC system at the same time. Performances analysis of the proposed double mitigating methods and optimization of parameters (scaling factor, depth factor and threshold) are also studied in this thesis. Performance of LDPC code combined with DC is also compared with other conventional clipping, blanking, conventional blanking/clipping (CJP) and adaptive blanking/-clipping (AJP) with LDPC by taking various levels of channel impulsiveness and noisiness. The obtained result show that the proposed noise mitigating algorithm achieved gain is 0.4dB,0.6dB,0.9dB, 1.4dB and 4.5dB as compared with AJP,CJP,blanking,clipping paired with LDPC code and LDPC coded alone ,respectively. Keywords: DC, IN, LDPC code, OFDM, PLC