Artificial magnetic conductor backed dual-mode sectoral cylindrical DRA for off-body biomedical telemetry

Abstract

This research investigates the potential of a sectoral Cylindrical Dielectric Resonator Antenna (CDRA) for biomedical telemetry. CDRAs are known for their low loss, ruggedness, and stability, but their limited bandwidth and size make them unsuitable for wearable devices. The research addresses these limitations by proposing a dual mode antenna that operates in EH110 and TE210 modes. The sectoral CDRA is a quarter segment with Perfect Electric Conductor boundaries, reducing its size by a factor of four. Mathematical derivations of the field components for both modes are derived to support the design. To minimize specific absorption rate (SAR), an Artificial Magnetic Conductor (AMC) surface is applied to the antennas backside, enhancing compatibility with the transverse electric modes. The antenna achieves a bandwidth of 0.7 GHz (5.2-5.9 GHz), suitable for biomedical applications, with a measured peak gain of 7.9 dBi and a SAR of 1.24 W/kg when applied to a human arm.