On the Diffraction and Line of Sight (Los) Centered Loss Modelling of VHF TV Signal over Hilly Terrain

Abstract

This paper discusses the diffraction loss due to obstruction and its analysis based ona single knife-edge diffraction method to arrive at a precise loss estimate. We supplement this study with the measurement data of continuous-wave propagating at 182.25 MHz over variable hilly terrain. After calculating the measured signal,we used the loss exponent estimated from the measured signal in computing the loss for the obstructed region, which we add with the diffracted loss. The analysis showed that the recommendations of the ITU-R diffraction model give a good agreement with the measured data. We proposed apropagation loss model dependent on the diffraction and line of sight (LoS).