Short Range, Close to Ground, VHF/UHF Propagation: A Comparison of Measured Results with a Simple Ray-Based Model

This report describes a VHF/UHF propagation prediction model and a series of field measurements aimed at verifying the results of the model. Comparisons between the model and the trial results were made at spot frequencies from 100 MHz to 900 MHz for several types of antenna and for various heights (not exceeding 2 metres) above ground level. The predicted path losses from the model were found to agree quite well with the results of the field measurements. It should be noted that the prediction model was never intended to be a comprehensive tool, merely a utility package which could be incorporated into other software. The program was written on an HP 9000 series model 310 computer using BASIC 5.1. This language has a set of commands which allow direct manipulation of complex values, consequently, translation into another language or version of BASIC not having these facilities will require extra programming. Great Britain.