Enhancing Performance of Antenna in Capsule using Parasitic Element for Wireless Capsule Endoscopies

This paper presents a simple configuration in which the external parasitic element of the capsule eliminates the influence of the lossy medium and improves the performance of the internal antenna for wireless capsule endoscopies (WCEs). It is validated using three different types of conformal capsule helical antennas based on flexible printed circuit board (FPCB). The proposed antenna achieves omni-directional radiation characteristics and simulated fractional bandwidth of 11.0% amid reduced influence of the lossy tissue.