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The first solid skin-equivalent phantom is developed to characterize the propagation channel for 60-GHz wireless body-centric systems. This phantom is designed to emulate the same reflection coefficient at the air/phantom interface as at the air/skin interface. It is fabricated by combining carbon black powder with polydimethylsiloxane (PDMS) and metallizing the resulting flexible carbon-PDMS composite on one side. Compared to the water-based semi-solid phantoms suffering from evaporation, this solid phantom allows avoiding the deterioration in time of the electromagnetic properties. This paper reports the design procedure and peculiarities of the phantom preparation. Using two open-ended waveguides, it is demonstrated, both numerically and experimentally, that the propagation along flat and cylindrical phantoms is similar to the propagation along the skin in the 58–63-GHz frequency range. The phantom is further validated using two dipoles and two wearable textile Yagi–Uda antennas demonstrating that it can be successfully used for propagation studies. [ABSTRACT FROM PUBLISHER]

The effect of textiles on propagation along the body at 60 GHz is studied. A Green's function representation is used to investigate analytically the field excited by an infinitesimal dipole over a multilayer structure representing a flat skin model and clothing. The propagation between two rectangular open-ended waveguides is studied numerically and analytically in terms of path gain. Furthermore, the effect of an air gap between the textile and phantom is considered. Results show that the presence of a textile over a skin-equivalent phantom, as well as an air gap between them, induces a typical decrease of the path gain by 2–5 dB, but it doesn't significantly affect the path gain exponent. In all considered scenarios the power decay exponent is around 3.6. [ABSTRACT FROM PUBLISHER]

It is demonstrated that an electro textile can improve thewave propagation at 60GHz 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%. [ABSTRACT FROM AUTHOR]