A residual frequency offset compensation scheme for OFDM system via SAGE algorithm

In this paper, we propose an iterative detection scheme in the presence of residual frequency offset (RFO) for orthogonal frequency-division multiplexing (OFDM) system using the space-alternating generalized expectation-maximization (SAGE) algorithm. In the proposed algorithm, the expectation step intends to remove the inter-carrier interferences (ICI) due to RFO in the received signals. Then, the maximization step is utilized to estimate the required parameters (i.e. RFO, data symbols and channel state information) using the ICI canceled signals. Simulation results present that the proposed algorithm shows almost ideal performance as long as the normalized RFO value is within 0.2.

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