The calculation of common volumes for rain scatter interference

Attention is given to the means for calculating the common volume and the effects of the use of realistic antenna gain patterns on the size of the effective common volume. Three types of calculations are presented: (1) the approximation of the main lobe by a Gaussian patterns, using numerical integration to produce the exact effective common volume; (2) the use of the same method, but basing it on a Gaussian main lobe and a suitable envelope for the antenna pattern; and (3) the situation of partial beam intersection.