Generalized impedance boundary conditions are derived for a planar, homogeneous, magnetic dielectric slab grounded by a perfect electric conducting plane and for a magnetic dielectric coated, perfect electric conducting circular cylinder. By invoking the duality principle, generalized resistive boundary conditions are also obtained for a planar, transparent dielectric slab. In the method followed here, it is not necessary to have a prior knowledge of the Fresnel reflection and/or transmission coefficients of the configuration under study to obtain the generalized boundary conditions. The boundary conditions developed here for the planar slab recover the exact Fresnel reflection and transmission (for the transparent slab) coefficients. Finally, the boundary conditions for the coated cylinder are used to obtain a solution for the scattering of an obliquely incident plane wave field, and this result is compared with the exact solution.

Exposure of the general public to electromagnetic radiation originating from randomly selected GSM/WCDMA base stations in Riyadh, Kingdom of Saudi Arabia has been assessed in the context of the International Commission on Non-Ionising Radiation Protection (ICNIRP) guidelines. The purpose of the measurement was to record the maximum power density of signals to estimate possible worst case exposure at each measurement location. These power density measurements were carried out at 60 mobile base stations located in different regions of the city. For each of these sites, three sectors were operational, yielding a total of 180 sectors. Two positions were identified per site with the greatest power density values. Exposures from these base stations were generally found to be in the range of 0.313 to 0.00000149% of the ICNIRP general public reference level, and the greatest exposure near any of the base stations was 21.96 mW m(-2) for a wideband measurement in the 75-3000 MHz frequency range. Analysis of the measured data reveals several trends for different mobile bands with respect to maximum exposure in those locations. Additionally, a simplified calculation method for the electromagnetic fields was used to compare calculated and the measured data. It was determined, on the basis of both results of the measurements and calculations carried out for these selected base stations, that members of the public would not be exposed to in excess of a small fraction of the ICNIRP guidelines at any of those sites. These are first such measurements to be made in the Middle East and provide assurance that exposures in this region of the world do not seem to be any greater than elsewhere.

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