Planar inverted-F antennas (PIFAs) made of woven conductive textiles and of patterns embroidered with conductive threads are investigated. The influence of conductive thread density on antenna properties is considered in both cases. The effect of lockstitch on antenna resonant frequency is quantified. A metallic button is proposed as the transition between textile antennas and classical circuits. A full-textile prototype of a PIFA is designed and shown to operate properly in the ISM 2.4 band.

Recently, an uniaxial multilayer cylinder cloak which does not scatter electromagnetic wave was proposed. However, the metamaterial realization only reduces the scattered field and is suitable only for excitation by a TM-polarized wave. Furthermore, it works only in a narrow frequency band. The purpose of this paper is to analyze such a cloak and to characterize the achieved "invisibility" in mathematical terms by calculating the scattered field and equivalent blockage width -the structure width that is actually "perceived" by EM waves. Therefore, mathematical analysis for TM-excitation is provided and the simulations are performed using the G1DMULT algorithm. The results show large sensitivity of reduction in the equivalent blockage width on the number of anisotropic layers used for cloak realization.

The electromagnetic wave propagation around human body torso is modelled by considering elementary electric and magnetic dipoles over an infinite muscle-equivalent cylinder. The poles in the spectral domain Green's function with smallest imaginary part are found to correspond to creeping wave propagation coefficients which predict the general trend in propagation around human body. In addition, it was found that axial magnetic field component is crucial for communication via creeping waves since it generates modes with smaller field decay compared to axial electric field. The developed model may thus serve as a practical guideline in design of on-body wearable antennas. The theoretical considerations are verified with simulations and measurements on the prototype of PIFA antenna placed on the human body.

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