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Nonparametric Doppler spread estimation for flat fading channels

Accurate estimation of the Doppler spread of a mobile radio channel is of significant value as it reveals the channel's rate of change. This information can then be used to improve the performance of many wireless communication subsystems. In this paper, a nonparametric technique is proposed to estimate the maximum Doppler frequency of narrow band fading channels. Moreover, a computationally efficient periodogram-based approach is formulated, and its finite sample performance is assessed and compared to parametric covariance-based estimators via computer simulations. On the basis of these comparisons, we claim that the simplicity of the proposed method, its accurate performance for small sample sizes in a wide range of propagation scenarios, and its robustness to low SNR conditions make it a strong competitor to the parametric approaches.