It gives me immense pleasure in bringing out this book which has the patronage of the student community all over the world . This book endeavours to provide a basic concept about OFDM communication .The main objective of this book is to study and compensate the Phase Noise problem in OFDM based communication system and enhanced the performance of the system in terms of bit error rate (BER) by using R-S coding with LSA channel estimation technique. Some other objectives of this book are (1) To analysis the BER Performance of Uncoded OFDM System without considering Phase Noise. (2) To analysis the BER Performance of Uncoded OFDM System at different values of Phase Noise. (3) To analysis the Comparison between Uncoded OFDM and R-S Coded OFDM System at different values of Phase Noise. (4) To analysis the Comparison between R-S Coded OFDM and R-S coded with LSA Channel Estimated OFDM System at different values of Phase Noise.