Minimization of path loss for a UWB communication link in a wireless capsule endoscopy system using antenna parameters

Abstract

Presently, Wireless Capsule Endoscopy (WCE) becomes popular for the diagnosis of GI tract diseases due to its non-invasive procedure. For further improvement of this technology, there is a need of a high speed telemetry system. One of the important parameters for analyzing the telemetry system is the path loss through the human body's channel. This paper investigates the path loss of an in-to-out human body channel for WCE system in Ultra Wide Band (UWB) frequency spectrum. A miniaturized UWB in-body capsule antenna is considered as a transmitting antenna and an UWB bow-tie antenna is designed and exploited for the receiving antenna. The effect of misalignment of the antennas and the effect of orientation of the antennas on path loss for a simplified human body channel are investigated. The finite integration technique (FIT) in CST Microwave Studio 2015 is used in the simulation. This paper shows that path loss minimization is possible by properly choosing the relative position, i.e., misalignment between the transmitter antenna and the receiver antenna. The paper also suggests that the rotation of the antennas has a significant effect on path loss minimization.