Hidden node margin and man-made noise measurements in the UHF broadcasting bands

This paper presents an extended study of the spectrum occupancy in the UHF frequency band (470-870MHz) in Spain and in Italy. The objective of the study is to establish by signal power measuring if cognitive devices are able to detect and distinguish in a Hidden Node scenario between empty and occupied TV channels. The study has been performed, for each of these two countries, at three different sites and at different heights over the ground for assessing the hidden node margin. The measurements in Spain were carried out in urban, suburban and rural environments close to the city of Bilbao while the measurements in Italy were carried out in Sardinia, in different urban areas of the city of Cagliari, surrounding suburban spots and a rural location 50 km west. The measurement methodology was the same in both scenarios. The results from the spectrum measurements performed in the various scenarios have been analyzed and conclusions have been drawn.