Research On Synchronization Algorithm For OFDM Systems

Orthogonal Frequency Division Multiplexing(OFDM) has been extensively used in the wireless communication systems .At present, OFDM technology has been used in many fields, such as wireless local network, digital audio broadcasting(DAB),digital video broadcasting(DVB)systems and so on. It is very promising to be a core technology of the fourth generation mobile communications. OFDM system is sensitive to symbol timing and carrier frequency offset very much so that it is probably to produce inter-carrier-interference. Therefore precise timing and frequency offset estimation and compensation is very important in OFDM communication system. Synchronization becomes one of major research topics in this domain.The synchronization of OFDM system is researched in this thesis, and the impact of synchronization on system performance is discussed in detail.First of all, the basic principles of OFDM system is introduced. Then, the various OFDM signal synchronization algorithms is discussed and the Cyclostationarity of OFDM signals is proved. In the end ,according to the Cyclostationarity of OFDM signals, we proposed a blind joint estimation of delay and frequency offset based on oversampling of OFDM system. The simulation results further proofs the applicability of the algorithm.