Radio wave loss deviation and shadow loss at 900 MHz

Abstract

Radio wave propagation between base and mobile stations is normally described as being Rayleigh distributed due to multipath interference. When the multipath is made up of a limited number of radio waves, the variations in signal amplitude follows a Weibull distribution. The transmission loss deviation has been defined as the dB difference between the 50 and 90% points on the Weibull distribution. Data will be presented showing loss deviation between 3 dB and 30 dB. Shadow loss over hills and around buildings are usually assumed to be knife-edge or rounded knife-edge. Shadow loss based on these assumptions is generally found to be less than the true measured value. Data will be presented comparing calculated shadow loss with measured values.