Comparison of site-specific radio propagation path loss predictions to measurements in an urban area

With high frequency portable communication systems becoming more common, the need for fast and accurate predictions of high frequency radio propagation in urban environments has rapidly increased. Until recently such predictions were usually based on empirical methods, especially if a relatively large number of predictions were required. But advances in both computational methods and computer speeds now allow for fast, site-specific predictions of radio propagation even in a complex urban area. We are primarily concerned with narrow band signal attenuation, but the methods presented are also applicable to signal delay and delay spread predictions. Measurements were made at frequencies of 900 and 1900 MHz.