An Implantable and Conformal Antenna for Wireless Capsule Endoscopy

This letter proposes an implantable antenna with ultrawide bandwidth operating in the medical device radio communications service band (401-406 MHz) for the wireless capsule endoscopy (WCE). The simulation and experimental results show the proposed antenna has a good performance in terms of the return loss and hence the bandwidth from 284 to 825 MHz. The maximum realized gain of this antenna is -31.5 dBi at 403 MHz. The maximum simulated input power is <1.7 mW in order to satisfy the specific absorption rate (SAR) regulations in the IEEE standard. The tolerance of the antenna owing to bendability and different WCE shell thicknesses is investigated. These indicate that the proposed antenna is a good candidate for the WCE.