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Abstract: The orthogonal method, a powerful and versatile array design procedure, is implemented to the synthesis of conformal slot arrays that reside on a perfectly conducting elliptic cone. In the design scheme, coupling between the slots is taken into account. The coupling information is derived through a numerically rigorous technique based on a full wave analysis. Two arrays, a circumferential and a quasi-radial, are synthesized. In the design examples, constraints on the side lobe level, on scanning capabilities and on cosecant pattern shaping are included.

Currently, standards for the compliance testing of wireless devices are being extended to cover a wider frequency band and different usage patterns of mobile phones as well as of novel body-worn and handheld devices. As a consequence, not only the head but also strongly varying tissue distributions of the body are exposed to electromagnetic radiation. Several authors have reported changes in the SAR absorption of body tissue due to the presence of a low permittivity fat layer. This paper identifies two different effects which can lead to increased SAR in layered tissue in comparison to the SAR assessed using homogeneous tissue simulating liquid: (1) for larger distances between the tissue and the antenna, standing wave effects occur depending on the frequency and fat layer thickness. (2) In the very close near-field (distances approximately ?/40), reactive E-field components lead to high local absorption in the skin. The latter effect occurs at lower frequencies and depends on the antenna type. Modification of the parameters of the homogeneous liquids cannot compensate for these effects. However, a conservative exposure estimate can be obtained by applying a multiplication factor between 1 and 3 to the values assessed using current experimental dosimetric techniques.

In this work, we highlight two issues that have to be taken into consideration for accurate thermal modelling with the finite-difference time-domain (FDTD) method, namely the tissue interfaces and the staircasing effect. The former appears less critical in the overall accuracy of the results, whereas the latter may have an influence on the worst-case approach used in numerical dosimetry of non-ionizing radiation.

In this work, a novel method is presented, with which the safe space around aperture antennas can be assessed. The basis of this new approach is the approximate similarity of the contours between uniformly and non-uniformly illuminated apertures. The isoparametric contours that result from numerical calculations have to be replaced by envelope contours that fully enclose them, in order to avoid radio frequency hazards. These envelopes were approximated with analytical formulas. Various examples of different apertures are presented, which demonstrate the mode of application and the validity of our method.