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[1] It is well known that interference of the human body affects the performance of the antennas in mobile phone handsets. In this contribution, we investigate the use of miniaturized metallodielectric electromagnetic band gap (MEBG) structures embedded in the case of a mobile handset as a means of decoupling the antenna from the user's hand. The closely coupled MEBG concept is employed to achieve miniaturization of the order of 15:1. Full wave dispersion relations for planar closely coupled MEBG arrays are presented and are validated experimentally. The performance of a prototype handset with an embedded conformal MEBG is assessed experimentally and is compared to a similar prototype without the MEBG. Reduction in the detuning of the antenna because of the human hand by virtue of the MEBG is demonstrated. Moreover, the efficiency of the handset when loaded with a human hand model is shown to improve when the MEBG is in place. The improvements are attributed to the decoupling of the antenna from the user's hand, which is achieved by means of suppressing the fields in the locality of the hand.Citation: Goussetis, G., A. P. Feresidis, G. K. Palikaras, M. Kitra, and J. C. Vardaxoglou (2005), Miniaturization of electromagnetic band gap structures for mobile applications, Radio Sci., 40, RS6S04,

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This paper is dedicated to Professor Jim James. It is a celebration of his life, career and world renowned research contribution to the engineering community. Jim was eminent for his pioneering research contributions to the fundamental understanding of radiation mechanisms in printed patch and small antennas including seminal achievements, both theoretical and in terms of demonstrated practical applications, in communications, radar and medical electronics. The paper includes a brief summary of his research. Details will also be included on some of his latest work involving low SAR material coated mobile handset antennas.

Previous studies have shown that monopoles loaded with material of equal permittivity and permeability values give increased bandwidth and radiation efficiency for a given size reduction. Positioning the monopole orthogonally to the head directs pattern nulls towards the head, which leads to low Specific Absorption Rates (SAR). Simulated results of the material loaded monopole showed dual-mode behaviour. In this paper, the simple monopole is translated into a compact antenna design suitable for mobile handsets. Metallic strips are printed on the material block to increase the number of modes and realise a small, quad-band, low-SAR handset antenna.