Reconfigurable multi-slot antenna for bio-medical applications

International audienceWe present a polarization- reconfigurable multi-slot antenna with four switchable linear polarizations (as 0⁰, ± 45⁰ and 90⁰) for implant communications. The design is based on four bow-tie shaped slots acting as radiators etched on a circular metallization plane with 45⁰ rotated sequential arrangements. RF switches based on PIN diodes are connected across each slot in order to modify the radiators polarization. We apply a differential source to feed the slot antenna through a ground-tapered Balun. In order to obtain a broadside radiation pattern, a reflector is placed at the quarter-wave distance below the radiator. Measured results are showing that the realized multi-slot antenna can generate four switchable linear polarization states with wide bandwidth and stable gain. This polarization diversity feature makes the proposed antenna highly attractive for implant and body-centric wireless communication systems for minimizing the multi-path distortion and polarization mismatching in the wireless channels