Research On Carrier Frequency Offset Estimation Algorithms In OFDM Systems

With the development of communication people require better communication quality and bandwidth. Orthogonal Frequency Division Multiplexing (OFDM) technology is one of the key technologies for the new generation of wireless communication. OFDM technology is an effective way to suppress multipath fading and improve the bandwidth efficiency. But the OFDM systems are very sensitive to Carrier Frequency Offset (CFO), which can seriously affect system performance. So CFO estimation has become the research foci of OFDM technology.In this thesis some classical algorithms for CFO estimation have been discussed in detail, including the performance analysis and computer simulation for each algorithm. Some improvement has been made for several algorithms. Firstly, the thesis introduces the emergence background, technical features of OFDM and the developing state of frequency offset estimation algorithms.Secondly, the affect of wireless fading channel on OFDM signal and the structure of OFDM systems are given. Several techniques in each part of OFDM systems are described.Thirdly, some classic estimation algorithms for carrier frequency offset are analyzed in detail. Then the performance of each algorithm is analyzed and simulated.Fourthly, some improved estimation algorithms for carrier frequency offset are proposed, and the simulation results further prove the feasibility of these algorithms.Finally, the thesis introduces the application of estimation algorithms for carrier frequency offset in DVB T systems.