Synchronization Of OFDM System Over Path Fading Channels

Along with the rapid development in field of multimedia the digital communication technique are expected to make the digital wireless communication systems more efficient. However, while researching and implementing such technology, several problems such as signal amplitude and phase distortion, which degrades the performance of the wireless communication system, needs to be encountered. Orthogonal Frequency Division Multiplexing and its related techniques because of its high band width efficiency, robustness to multipath and pulse noise, high transmission speed and flexible modulation on subcarriers has found its wide applications in a lot of scientific fields. The prime defects of OFDM system are its high sensitivity to synchronization errors. At first the paper does research on the different type of synchronization problems in OFDM transmission system.At first this thesis introduces the principle and structure of the multicarrier transmission and discusses the basic principle of the OFDM system along with its system model.After that it analyzes the synchronization process in the OFDM system, its’ basic principle and different techniques associated with it namely carrier frequency synchronization, symbol timing synchronization and sample timing synchronization along with related theoretical mathematical algorithms. Following the analysis of different techniques. The thesis explains different kind of synchronization offsets or errors experienced by the OFDM system and analyzes the impact created by different kinds of offsets namely carrier frequency offset, symbol timing offset and sample timing offset.Last but not the least the thesis introduces the SC algorithm analyzes the drawback in it and then proposes an enhanced algorithm, which is more reliable and effective to ensure the precision of timing synchronization and removing the peak plateau problem and the timing ambiguity. The enhanced method reduces the bit error rate in an OFDM system improving the performance of the digital communication system.