Comparison and Evaluation of Doppler Spread Estimation Algorithms in WCDMA

Abstract: In a WCDMA transmission systems, the properties of the radio transmissionchannels can be strongly aected by the movement of User Equipment (UE) orthe surrounding objects. The estimation of Doppler spread is therefore of greatimportance since it is closely related to the mobile speed, as it can also be usedto characterize the fast fading in the radio channel. Thus the Doppler spread estimation can have wide range of applications and the relative research on thistopic has drawn much attention. Many Doppler spread estimation algorithms has been proposed in the literature. In this report, these algorithms are divided into four categories, and the comparison is performed from both performanceand implementation point of view to compare these four types of estimators. During the investigation, the Rayleigh fading and Rician fading model withdierent mobile speed and SNR are simulated to analyze the performance of estimation algorithms under dierent conditions. The effect of Rician factor and angle of arrival of Line Of Sight (LOS) component is also taken into consideration in the evaluation. Furthermore, the computational complexity of each algorithm is calculated. Based on simulation results, the underlying reasons for their performances are analyzed individually. The Moser's estimator (correlation based estimator) demonstrates the best performance among these four estimators from the perspective of estimation accuracy. And it also shows the great value for the implementation in real systems.