الفهرس 
Wireless Capsule Endoscopy System (WCE)Only 14 pages are availabe for public view
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Abstract
This thesis addresses the study and design of implantable antennas for wireless
biotelemetry applications. The wireless capsule endoscopy (WCE) system
requirements are be presented. WCE records images of the human body digestive
tract and transmits it wirelessly to the receiving unit. In this thesis a proposed
design of a linearly polarized sunflowered with conformal monopole antenna
dedicated for wireless in-body capsule endoscopy applications at 2.4 GHz. The
designed antenna offers an advantage of very small size equal to radius of capsule
dome. Also, a circularly polarized quadfilar or octafilar helical antenna (QFHA or
OFHA) investigated for wireless in-body capsule endoscopy applications. The use
of a circularly polarized antenna permits a freedom in capsule orientation during
endoscopy process. A multi-layered cylindrical model and homogenous cubic
model for the human body tissues are studied and compared. The radiation
characteristics of the QFHA and OFHA are encapsulated and placed inside the
human model. Both the QFHA and the OFHA in capsule module are designed to
resonate at 2.4 GHz with an impedance matching bandwidth of 125 MHz. The
effect of the capsule orientation on the performance of the endoscopy process is
explained. The response of then OFHA with and without capsulation is studied and
introduced. The radiation characteristics of the QFHA and OFHA antennas in
different cases are fully analyzed and investigated using the finite integral
technique and the result compared with that calculated by finite element method.
A 4-arm curl antenna at 2.4 GHz is presented. The antenna arms are sequentially
fed to enhance the circular polarization characteristics. The antenna is
encapsulated and implanted in the human body. The radiation characteristics of
the encapsulated 4-arm curl antenna inside the human body are investigated. The
orientation of the WCE inside the human body is demonstrated. The performance
of the capsule in free-space with the same dimensions is investigated. The effect
of capsule orientation during its travel through the digestive tract on the gain and
radiation efficiency has been explained.