VHF and UHF Doppler radars provide a unique database to estimate the refractivity structure constant Cn 2, eddy dissipation rate &egr;, and vertical flux of horizontal momentum. Using the data collected from the Indian MST radar, these parameters are studied at a tropical latitude. The refractivity turbulence structure constant is estimated from the backscattered power of the received echoes. Cn 2 (radar) and Cn 2 (model), derived from radiosonde observations, are compared, and a fairly good agreement is seen. Diurnal and seasonal variations of Cn 2 are also presented. The eddy dissipation rate is estimated from the radar echoes employing the power and spectral width methods. A fairly good agreement is seen between the two methods. Values of &egr; are found to vary from 10-6 to 10-3 m2s-3 in a height range of 4--19 km. Cn 2 and &egr; are observed to be minimum during a moderate jet stream wind of 50--60 m s-1. Vertical flux of horizontal momentum is computed using the symmetrical two-beam method. Significant fluxes of westward and northward momentum are observed, and the values lie in the range of -1 to +1 m2 s-2. The implied accelerations are also estimated. The results presented are largely consistent with the results available in the literature.¿ 1997 American Geophysical Union