Raytracing analysis of microwave link fading

A raytracing model of propagation provides the basis for developing a dependable qualitative fade analysis technique. A qualitative analysis is conducted by interpreting ray trajectory relationships in the modeled link environment. Fade analysis examples correlated to actual test data demonstrate that interpretation of raytracing graphics can identify the fade mechanism(s). The good agreement between measured field data and raytracing analysis has provided the opportunity to predict the propagation behavior on proposed links without having to resort to on-site testing. This technique is used to evaluate alternative antenna height and alignment angle solutions for surface reflection cases. Since the atmosphere is constantly changing, the raytracing model must be able to accept varying environmental data and update the display accordingly. A PC-based, interactive raytracing program with this capability allows the rapid simulation of successive fade events