Broadband hybrid water antenna for ISM-band ingestible capsule endoscope systems

A broadband hybrid water antenna for ingestible capsule endoscope systems at Industrial, Science and Medical (ISM 2.45 GHz) band is proposed. The proposed antenna consists of a cylindrical conducting monopole antenna, saline-water, and a biocompatible shell. The antenna has a wide -10 dB reflection coefficient bandwidth from 1.89 GHz to 4.51 GHz (a fractional bandwidth of 106.9%) with a compact volume (approximately 1.53 cm
³
). To evaluate the effects on the antenna performance, electrical components (battery, camera, and transceiver) are modeled as a PEC cylinder inside the capsule. In addition, the specific absorption rate (SAR) performance of the proposed antenna is also analyzed by SEMCAD.