Challenges in Optimizing The Microstrip Patch Antenna for Endoscopy Application

Abstract

Wireless capsule endoscopy using noninvasive antennas have got more attention compared to the traditional endoscopy. Designing of transmitting antenna in wireless capsule endoscope (WCE) is a challenging task as it is placed inside the human body compared to receiving antenna placed outside the human body. The main challenges of these antennas include achieving high data rate of the telemetry system, miniaturization, omnidirectional radiation pattern, allowable specific absorption rate (SAR) value, and wide bandwidth simultaneously. This is because of the various sections of gastrointestinal tracks having different thickness and dielectric constants. In WCE system, the conformal antenna can get placed on the surface of capsule leaving the interior open for other electrical components. So, the miniaturization can be achieved up to a great extent. It gives wide bandwidth but at the cost of SAR. To overcome these challenges, one need to characterize the antenna for WCE application. This paper initially discusses about the various requirements of patch antennas in WCE and later discuss about while achieving these requirements, what are the effects of physical parameters of antenna are taking place on those requirements. Further, paper discuses about how these effects can be minimized by doing trade-off between the various performance parameters in antenna designing for WCE application. The study of these effects is characterization of patch antenna. Paper also discusses about various challenges that can occur during optimizing the patch antenna for endoscopy application. Later, remedial solutions are proposed to overcome these challenges.