Research On Carrier Frequency Offset Estimation Algorithms In Orthogonal Frequency Division Multiplexing(OFDM) Systems

Orthogonal Frequency Division Multiplexing(OFDM)has been extensively used in theareaofradio communication systems,itwillbethebasictechniqueofthefuturebroadband radioaccess system,and also has been considered as the core technique of future mobilecommunication system．Cartier frequency offset is the key problem to use OFDM,soresearchers recently focus on it． This paper simply introduces the emergence,development,basic working theory,characteristics and the merits of OFDM systems．Four calTier frequency offset estimationalgorithms are respectively discussed about their chief theories,classical algorithms andproblems that they have．Then it proposes some new modified methods to estimate CalTierfrequency offset． With the basic MLE,SCA algorithms and MUSIC-Like,ESPRIT-Like which belong tothe subspace cartierfrequency Offset estimation algorithms being researched,they are simulatedrespectively．Then this paper modified the combination method,itfirst attains more exact timingestimation based on MLE,then estimates entire frequency offset based on SCA．Simulation results show that this new method is of better precision and little computation．Two Novel algorithms belonging to classical subspace method,LS—ESPRIT and TLS-ESPRIT,are also proposed to estinaate carrier frequency offset．They have the same even better estimation performance as ESPRIT-Like．At the end ofthis paper a simple simulation about appfication estimation algorithms to OFDM systems shows that they are feasible and efficient to maintain good system performance．...