Path loss prediction of electromagnetic wave from the micro power

Results of the measurement of electromagnetic waves from the micro power conducted in short-distance environments at 900 MHz and 1800 MHz are presented. The data were obtained in four different environments in Beijing. Some analytical models are presented to predict the path loss in short distance. These models show that the path loss exponent value is close to the value n=2 in a suburban open field environment which is for free-space propagation, and is n=3 or so in other three urban environments.