Anda R. Guraliuc

Enhancement of On-Body Propagation at 60 GHz Using Electro Textiles

It is demonstrated that an electro textile can improve the wave propagation at 60 GHz along and around the body. To this end, an analytical formulation is implemented to evaluate the electric field excited by an infinitesimal dipole over a flat skin model with and without an electro textile layer. To validate the analytical results, the propagation is characterized numerically and experimentally for two rectangular open-ended V-band waveguides placed over a skin-equivalent phantom. Path gain values for flat, cylindrical, and elliptical cylinder phantoms are provided. Results show that placing an electro textile over a skin-equivalent phantom allows increasing the path gain by 5-15 dB. In addition, it has a shielding effect by decreasing the power absorption in the body by more than 95%.

Millimeter-wave electromagnetic field exposure from mobile terminals

In the context of the fast development of millimeter-wave (mmW) technologies for future 5G cellular networks and concerns related to their possible impact on the human health, this paper introduces a first analysis on the mmWs interaction with the human body. Firstly, the main regulations on the exposure limits at mmWs are reviewed. Secondly, an investigation on the skin modeling in terms of homogeneous vs. multilayer model is performed. In particular, power reflection coefficients and power density distributions are compared for different models. Our results provide an insight on the choice of an appropriate human body model for dosimetric analysis in the 60 GHz band.

On-body propagation at 60 GHz: Impact of a textile presence

Effect of regular or electro textiles on the on-body propagation at 60 GHz is presented. It is analyzed analytically, numerically and experimentally. The presence of regular textiles (e.g. cotton or felt) covering a skin-equivalent phantom produces a typical path gain decrease of 2-5 dB, without significant changes of the power decay exponent. On the other hand, the use of an electro textile allows increasing the path gain by 5-15 dB.

PDMS-based skin-equivalent phantom for propagation studies in the 58–63 GHz range

A solid phantom simulating the same reflection coefficient at the air / phantom interface as at the air / skin interface is developed for on-body propagation assessment in the 58–63 GHz range. The phantom consists in a grounded lossy dielectric sheet made of polydimethylsiloxane (PDMS) and carbon black powder. The paper describes the characteristics of the phantom and provides an example of its application in propagation studies at 60 GHz.

Tissue-equivalent phantoms in the 60-GHz band and their application to the body-centric propagation studies

Experimental tissue-equivalent phantoms represent an essential element for accurate evaluation of antenna / human body interactions as well as for body-centric propagation measurements. The paper is focused on recent advances in design of tissue-equivalent phantoms in the 60-GHz band, in particular on semi-solid and solid phantoms. Recently developed prototypes are presented and compared. Some application examples for propagation measurements are provided, demonstrating that these phantoms can be successfully used for such applications.

Characterization of on-body communications at millimeter waves

This paper presents a the study of on-body communications at millimeter waves. An analytical formulation is proposed by assuming a dipole source radiating on a flat skin, whose permittivity is suitably chosen to model human tissues at those frequencies, according to previous investigation. An experimental setup, consisting of two open-ended waveguides placed on the top of a skin-equivalent phantom, is then discussed in order to validate the theoretical analysis.