Robust Doppler spread estimation in nonisotropic scattering environments

A new parametric approach is proposed for estimation of the maximum Doppler frequency, or equivalently the mobile speed, in narrowband mobile radio channels. Such information is of interest as it reveals the channel´s rate of change, which can be used to improve the performance of many wireless communication subsystems. In this work, simple and efficient Doppler frequency estimators are formulated based on using a small number of samples of the channel autocorrelation function. Unlike previous approaches, the chosen parameterization is shown to be robust in a microcellular propagation environment, which may be characterized by nonisotropic scattering and/or a specular component. Simulation results are described to illustrate the effects of additive noise and the finite data record performance.