Summary
International Symposium on Antennas and Propagation
2008
Session Number:3C23
Session:
Number:3C23-4
Base Station Antenna Equivalent Apertures Theory
A. A. Nanos, K. Siakavara, T. Samaras, J. N. Sahalos,
pp.-
Publication Date:2008/10/27
Online ISSN:2188-5079
Summary:
The field estimation near mobile base station antennas (BSA) is of paramount importance for safety studies of the general and occupational population. For safe space exclusion studies, one sometimes resorts to less accurate techniques, which can though determine reliably the outer space field value peaks. Two such methods, already presented in the literature, are the gain and the synthetic based model, [1]. These estimate the field in the near zone of a BSA comprised of dipoles backed up by reflectors, combining the far fields of the constituent unit cells. The method presented in this work, substitutes each unit cell by an equivalent uniformly excited rectangular cross section aperture, whose dimensions are estimated so as to give the same half power beamwidths as those of the unit cell in the two main planes. The electric and magnetic fields iso-contours of the actual and equivalent sources are shown to have common form in the near zone, after appropriate normalization to an arbitrary reference distance of the far field. The method has been applied successfully to large circular and elliptic apertures, [2]. Simple and fast equations for the near field evaluation of uniform planar sources have also been given, [3].