Prediction of hilly terrain diffraction loss experienced by microwaves

The investigation consisted of carrying out signal loss and polarisation measurements using 20 radio paths ranging in length from 3 to 10 km planned over the measurement area which is approximately rectangular in shape measuring 20 km by 12 km. This area proved to be very useful in the study of diffraction loss by terrain features as it contained six almost parallel valleys running north to south which form an undulating landscape providing a cross sectional path profile ranging in height from 100 m to 500 m above sea level. Simultaneous measurements of both co-polar and cross-polar components of the received signal were taken and for each radio path a set of readings consisting of 100 such signal levels (co and cross-polar values) were taken to provide information on the variability of the signal caused by wind movements