A statistical comparison of spaced antenna and spatial interferometry methods for estimating horizontal winds in the troposphere and lower stratosphere is presented. The data analyzed were obtained with the middle and upper atmosphere radar from 1910 LT on June 29, 1990, through 0950 LT on July 2, 1990. At all heights, velocity estimates based on frequency domain analysis are within 4% of those based on the time domain analysis. We conclude that frequency domain techniques provide an alternative method for estimating the so-called true velocity. It is not clear, however, that they offer a significant advantage over the time domain methods. Some analysis parameters are easier to extract in the frequency domain, while others can be extracted more easily and efficiently in the time domain. ¿ American Geophysical Union 1993