Feedback frequency synchronization for OFDM applications

Maximum-likelihood estimation methods are often used to derive carrier freq uency recovery schemes for digital receivers. Unfortunately, their rigorous application is generally hindered by analytical difficulties and, in conse quence, some approximations must be made to achieve practical results, In t his paper we concentrate on frequency recovery for Orthogonal Frequency Div ision Multiplexing signals. Following Daffara and Chouly [1], we derive a f eedback synchronizer based on maximum-likelihood methods, Making different approximations, however, we come up with a scheme that is superior in terms of estimation accuracy Comparisons are also made with other feedback schem es based on heuristic reasoning.