Advanced Time and Frequency Synchronization Techniques for OFDM Systems

The Orthogonal Frequency-Division Multiplexing (OFDM) is a multi-carrier modulation technique in which data symbols are transmitted in parallel over orthogonal sub-carriers. It has been adopted in several broadband wireless communication systems thanks to its numerous advantages namely high spectral eciency immunity to multipath distortion and simplicity of the receiver architecture to support high data rates and user mobility. However OFDM systems are very sensitive to synchronization errors which destroy the orthogonality between sub-carriers resulting in an important performance degradation. Hence it is important to implement ecient and relevant synchronization algorithm at the OFDM receiver side. In addition to the relevance features the overhead introduced by the insertion of dedicated synchronization signals and the occasioned computational load should also be considered.