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Multiple Autocorrelation Function-based Maximum Doppler Frequency Estimation

In this paper, we introduce a maximum Doppler frequency estimation scheme based on autocorrelation function (ACF) and propose a modified ACF-based method for orthogonal frequency division multiplexing (OFDM) systems. The traditional ACF-based estimation scheme has a trade-off relationship between estimation range of the maximum Doppler frequency and the corresponding performances such as convergence time and steady-state jitter. Since this relationship depends on correlation interval between two OFDM symbols, it is important to design a flexible algorithm in known channel environment. In this paper, we analyze the characteristics of the ACF-based estimation scheme and propose an algorithm to guarantee stable performances such as estimation range and steadystate jitter regardless of correlation interval. Simulation results verify that the proposed method can improve the overall estimation performance in time-varying Rayleigh fading channel environment.