434 MHz ISM band antenna for in-body biotelemetry capsules
Abstract
We propose a versatile 434 MHz in-body capsule antenna suitable for ingestible and variety of implantable applications. The low profile conformal antenna is synthesized using a hybrid analytical–numerical approach and optimized for robust operation at 434 MHz inside a 17 mm long biocompatible encapsulation (7 mm diameter). The antenna remains matched below –10 dB in wide range of body tissues (from 42% of muscle electromagnetic properties up to the maximum tissue electromagnetic properties). A realized gain is –22.4 dBi and radiation efficiency reaches 0.4%. The radiation performance of the proposed antenna exceeds most of counterparts whereas its impedance characteristics are more robust.