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An Iterative Maximum Likelihood Synchronization Method for OFDM System
Department of Communications, Navigation and Control Engineering, Taiwan Ocean University, Keelung, Chinese Taipei
Department of Communications, Navigation and Control Engineering, Taiwan Ocean University, Keelung, Chinese Taipei
- 1 Department of Communications, Navigation and Control Engineering, Taiwan Ocean University, Keelung, Chinese Taipei
- 2 Department of Communications, Navigation and Control Engineering, Taiwan Ocean University, Keelung, Chinese Taipei
Communications and Network·Volume 05 (2013)·Pages 43–47·Published 30 May 2013·DOI10.4236/cn.2013.52B008
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Abstract
OFDM system divides a wideband transmission bandwidth into several overlapped narrowband subcarriers to avoid the serious frequency selective fading problem. However, if Timing Offset (TO) and Carrier Frequency Offset (CFO) exist between the Transmitter (Tx) and Receiver (Rx), OFDM system will suffer the Inter-Symbol Interference (ISI) and Inter-Carrier Interference (ICI) that degrade the system performance dramatically. In this paper, we propose an iterative maximum likelihood method for synchronization. We also adopt the overlap concept to reduce the plateau problem. Simulation results show that the proposed method can predict the time delay and frequency offset correctly even under the multipath fading scenarios.
KeywordsSynchronizationMaximum LikelihoodOFDM
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