Path Loss Prediction Model for Propagating Radio Wave in Woodland

This paper presents new empirical prediction models for loss estimation in forest environment. Experimental investigations were carried out on groups of trees in form of woodland and lines of trees at SHF band under different operational contexts. In the experimentations, two major measurement geometries (propagation “into” and propagation “inside” forest) were adopted on site to site basis. Results from all the sites displayed a common trend, in that they all showed a persistent decay in signal power with the depth of vegetation and which is dependent on the measurement geometries.

Using a “Power Law” theory, a new empirical loss prediction model has been proposed for each propagation scenario using parametric equations which are in line with the general formulations of the ITU-R models. These new models were tested with the standard empirical loss prediction models and gave a statistical adherence with the fitted ITU-R model.

It is anticipated that these new models will address the inadequacy in the existing prediction models which have not taken cognizance of the differences in operational contexts of each propagation scenario in their formulations.