Since October 1983, a new HF radar facility has been operated from Goose Bay, Labrador, for the purpose of studying high-latitude ionospheric irregularities. In this paper, we present autocorrelation functions of the backscattered signals from these irregularities and show how these are processed to yield information on the drift velocities of the irregularities. Since the radar is typically operated in an azimuth scan mode, the Doppler data derived from the autocorrelation functions may be used to study the two-dimensional structure of the irregularity drift. A procedure is presented for this analysis, and it is shown that the results are reasonably accurate during periods in which the irregularity drift is approximately uniform. However, if the flow is nonuniform, as it is the vicinity of the cusp and in the midnight local time sector, then the procedure leads to erroneous results. We consider the implication that these results have an azimuth scan measurements of plasma drift with incoherent scatter radars, and we present possible ways in which measurements might be made under nonuniform flow conditions.