Side lobes from radio base station antenna in the evaluation of human exposure to EMF

Maximum human exposure to electromagnetic field associated to a base station is, usually, due to the main lobe of the antenna and is located in the range of some tens to a few hundred meters from its mast. In this paper, we discuss practical situations in which the side lobes of the antenna is responsible for the maximum exposure in distances closer to the base station, even transporting less energy than the main lobe. It will also be presented guidelines to estimate what portions of the pattern of the antenna contributes to the highest field strength. This guidance may be used when few radiating system information is available, like gain, height, tilt and vertical half-power angle, and side lobe level.