Blind Symbol Timing Estimation for Orthogonal Frequency Division Multiplexing Based on Non-Gaussianity Maximization

Abstract

This paper proposes a blind symbol timing estimator for orthogonal frequency-division multiplexing (OFDM) systems. The basic idea lies in that compared to the scenarios with timing offsets, the distribution of the received signal within one OFDM symbol in the frequency domain is less Gaussian when the start of the discrete Fourier transform window is locked into the safe region. Thus via minimizing the kurtosis employed to measure the non-Gaussianity, the symbol timing estimation is achieved. A two-step implementation is introduced to balance between the estimation accuracy and computational complexity. It is proved that this estimator is also applicable in multiple-input multiple-output systems, including multiplexing- and diversity-based configurations. Numerical simulation is carried out to confirm the effectiveness of the proposed method and give the performance comparison with existing blind schemes in terms of the probability of lock-in and bit-error rate.