A STUDY OF INTERPOLATION OF TOPOGRAPHICAL MESH-DATA TO DERIVE TERRAIN PROFILES FOR PROPAGATION PREDICTION

Abstract

This paper describes some methods for interpolation of the topographical mesh-data in order to derive terrain profiles which are essential especially to predict the terrestrial radiowave propagation. The mesh-data provide ground heights at specific locations at regular intervals of 50m or 200m. Heights for intermediate locations must be obtained by interpolation of nearby heights. The interpolation is carried out first along a propagation path, and then across the path at key locations, such as mountain peaks. The two methods of interpolation, Everett-Newton's and Rectangle methods, are applied and compared. Both of them fairly meet our needs comparably.