An optimized Double-Dwell frequency synchronization algorithm for OFDM signals

Abstract

In this paper, we propose a Double-Dwell (DD) Carrier Frequency Offset (CFO) estimation algorithm for Orthogonal Frequency Division Multiplexing (OFDM) signals. The proposed scheme is based on a two-stage correlation operation to provide an initial coarse estimate of the carrier offset followed by a much finer search to improve the accuracy. The search step size and search window are varied to optimize the operation of the proposed scheme in order to minimize the mean-square error (MSE). Simulation results under both AWGN and flat fading channels are presented in this paper. It is shown that the proposed DD scheme provides an improvement in MSE of about two-order of magnitude when compared to conventional single-dwell (SD) scheme without increasing the computational complexity.