Epidermal Loop Antennas

Abstract

The Quadruple Loop (QL) antenna was designed and investigated to deliver a robust body-worn antenna for bio-medical applications. The QL antenna is a very thin single-layer groundless structure which allows for the installation of neighboring electronics and sensors on biomedical device. The initial research objective was achieved after measurement results confirmed the superior performance of the QL antenna to the standard square loop. This was evident in gain and bandwidth improvement after the inclusion of the four circular patches to the original loop. In the second research stage, different fabrication tools and materials were used to make a number of QL antennas. The different antennas were intended to operate as GSM-900, GSM-1800, and BLE epidermal antennas. Radiation pattern measurements were conducted to compare their results with their simulation counterparts. Later, data communication tests showed that the acquired BER readings could qualify the BLE and GSM-900 antennas to work as part of 4-QAM wireless links. Moreover, a stretchable QL epidermal antenna made of novel silver ink had its measured results agree with simulations. Besides these hands-on endeavors, numerical analysis was used to explain the low values of gain of epidermal antennas. This is added to finding an equivalent and more efficient mathematical model of biological tissues which make up the human arm. The equivalent model was tested in software and has the practical potential to be realized in physical phantom making.