A.17.14.3.1 SEAMCAT Specific Implementation

The site-general propagation models from §4.1.1 and §4.2.1 are valid only for a given range of Tx-Rx 3D distances ,  If the Tx-Rx 3D distances in the simulation scenario are outside this range, SEAMCAT will inform the user about that in a consistency check before the simulation starts. The simulations can still be run and the values of the basic transmission loss will be computed using the formulas from Recommendation ITU-R P.1411 even for distances that are outside the range of validity.

A special care needs to be taken for distances  as they can result in non-physical values of the basic transmission loss that can be smaller than free-space loss, or even be negative. In that particular case, the median values of the basic transmission loss are capped from below by the free space loss as follows:

Compute PL=PL_1411
if d<d_min:

Compute PL_FreeSpace
PL=max⁡〖(PL,〗  PL_FreeSpace)