Site diversity is considered to be an effective technique to overcome severe rain attenuation in satellite communication links. In the present paper, a modification of an existing method to predict the improvement in using dual/triple site diversity techniques is proposed. The modified method assumes a more complicated but realistic model for the description of the rain height. The present results are compared with a representative set of available experimental data taken from operated links. The difference between the existing predictive results and the deduced ones after use of the modified procedure, for various geographic latitudes and climatic zones, is also examined.