Single knife edge diffraction propagation studies over a hilly terrain

Field strength measurements are made to study the single knife edge diffraction propagation in the hilly terrain of Tirupati, southern India. TV signals originating from Narayana Giri Hill in the VHF band are monitored at 4 different locations of Tirupati for this purpose. The observed values are converted into path loss values and are compared with prediction techniques. An attempt is made to study the adaptability of these techniques and it was found that the ITU-R, Epstein-Peterson (1953), Deygout (1966) and Edward-Durkins (1969) methods are in closer agreement with the observed path loss where as Blomquist-Ladell (1974) over estimates the observed path loss.