In this work, analyses of threshold detection and phase difference techniques for wind speed measurement using ultrasonic transducers are presented. The influence of uncertainties associated with additive noise and attenuation of the ultrasonic signal on the wind speed measurement uncertainty is analyzed. A dala fusion procedure based on the Maximum Likelihood Estimation Algorithm is developed for the determination of the wind speed. Data are gathered using the threshold detection and phase difference technique. The data fusion procedure provides a lower measurement uncertainty than those obtained through the above techniques when taken separately. Practical design issues are considered and an application example is shown in order to illustrate the proposed procedure. © 2007 IEEE.