An efficient method of EM field modification around transmitting stations

Abstract

An efficient practical method for the electromagnetic (EM) fields reduction around transmitting stations has been developed. The project has been stimulated by the necessity to reduce the field levels in the vicinity of transmitting stations, including FM, UHF, cellular base stations and other radiocommunication services, to obey regulations concerning human protection against electromagnetic radiation. The main constraint in the optimization procedure is the requirement to preserve the radiated power ERP of a service in operation. The method joins accuracy with high efficiency, and is based on 3 stages procedure using the antenna numerical models of different levels of approximation. An example is given of its application to a real case of transmitting stations in which the levels of measured EM exceeded the safety limits.

Index Terms
antenna systems; human exposure assessment; non-ionizing radiation; electromagnetic fields (EMF); radiation limits; radiation patterns