Determination of General Public Exposure to WiMAX Base Stations

This paper deals with general public exposure to WiMAX base stations. In Germany, some networks are already in use, which operate in the licensed 3.5 GHz and in the licence-free 5 GHz frequency bands. Using a frequency selective measurement method with extrapolation to maximal operational state of the station it was found, that typical exposures are in the range of 0.003 to 1.4% of the ICNIRP 1998 field strength reference levels. As with mobile phone base stations, distance to the station is not a reliable estimate for exposure, but orientation to the main lobe is. Exposure to stations operating in the licensed band is more than 25 dB higher than for stations in the unlicensed band. A comparison with UMTS stations on the same roof or in the near vicinity shows on average a 13 dB higher exposure to the UMTS stations.