الفهرس 
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Abstract
Nowadays, a lot of considerable attention is being directed towards biomedical telemetry
devices, which are attached to the patient’s tissue for daily monitoring of physciological
and pathological information, such as blood pressure, temperature, glucose monitoring, a leadless pacemaker, etc. Besides, these devices can be utilized in the exchange
of this information. Based on the physciological and pathological information, the patient’s treatment will take place without the need to visit a hospital for examination
and diagnosis. Thus, for wireless capabilities, wearable and implantable antennas are
prime components of implantable medical devices (invasive) and wearable devices (noninvasive) to establish bio-telemetry links.
Communication between devices can be classified into three categories according to the
method of communication. The on-body communication is a communication between
the nearby worn devices, while the communication between the body-mounted device
and the remote device is an off-body communication. For implantable medical devices,
communication is performed with a worn device and a body-centeric device. In this thesis, various bio-telemetry antennas are designed. Then, the communication link between
these antennas is evaluated for various cases as described above.
This thesis provides compact implantable and wearable antennas. The antennas are
simulated and optimized with the aid of computer simulation technology (CST). First,
a wide-band, low-profile antenna with a circularly polarized (CP) merit immersed in a
lossy medium is designed. This antenna works in the 2.4–2.4835 GHz and 5.725–5.875
GHz industrial, scientific, and medical (ISM) bands. The main features of the designed
antenna are its simplicity, the wide-band characteristics, which preserve the detuning
effect caused by environmental heterogeneity, and the CP property at both operational
ISM bands. Moreover, for introducing an electrically small antenna footprint with proper
performance, the implantable antenna is designed with an entire size of 25.4 (5× 5 ×
1.016) mm3
. This antenna is designed and dissected in a homogeneous skin model (HSM)
as well as a three-layer phantom. In addition, the antenna performance is measured and
evaluated in chicken slab as well as in a saline solution. For skin tissue emulation, the
liquid phantom was prepared and tested using an open-end coaxial probe in our Lab.
The measured impedance BWs are 13.04 % and 33.2 % in the chicken slab, while 19.5%
and 25.2 % in the saline solution at the two ISM bands, respectively. Finally, the link
budget and safety considerations are evaluated for ensuring reliable communication of
the designed implantable antennas and patient safety. Second, a triple-band antenna
with CP behavior embedded in a lossy tissue is introduced. The triple bands are the ISM
(868–868.6 MHz and 2.4–2.4835 GHz) bands and the midfield band (1.824–1.98 GHz).
These bands are used for physiological information telemetry, power-saving, and wireless power transfer in medical devices. CP behavior at three bands is the key feature of the
designed implantable antenna. Moreover, the size of the designed antenna is compact
of 50.8 mm3
.
Third, a flexible wearable antenna integrated with Rogers material as well as jeans
fabric material operating at 2.45 GHz is proposed for bio-telemetry applications. These
substrates are chosen due to their flexibility and conformability in worn scenarios. The
compactness of the designed wearable antenna with a coplanar waveguide (CPW) is
carried out by using six rectangular slits at the right and left edges and etching centeral
slits from the upper edge of the radiator. Besides, two triangles are cut from the ground
plane. Meanwhile, the impedance matching of the designed antenna is enhanced by
adjusting two triangle slots on the ground plane. For operating the antenna at the
desired frequency, four L-shaped elements are added at the corners of the rectangular
patch. As the antenna is designed for wearable applications, it is also analyzed on a cubic
model consisting of four layers mimicking human tissue. Then, this antenna is backed
by a flexible as well as semi-flexible AMC periodic structure for enhancing the gain,
reducing the SAR value, and increasing the impedance BW in off-body and on-body
cases. Besides, for verification, the wearable antenna is fabricated on the two flexible
substrates and then evaluated when mounted in four different places on a male body.
Finally, communication between implantable antenna and on-body antenna and offbody communication between wearable and off-body antennas integrated with 3 × 3
AMC array are evaluated. For implantable communication, a dual-band implantable
Tx antenna and an on-body Rx antenna are proposed working in the 2.41 and 5.81
GHz ISM bands. A flexible on-body antenna with a compact size and wide band is
designed for patient comfort. The designed antenna begins with a conventional patch
antenna that has a partial ground plane. However, in order to achieve a low profile
and improve impedance matching, a center slot is loaded on the radiator to increase
the capacitive effect. Furthermore, two meander lines are etched to expand the current
path for shifting the frequency down and enhancing the impedance matching. Then,
parasitic element is etched on the ground plane for operating at desired frequencies.
The transmission coefficients between two antennas in implantable communication and
off-body communication cases are evaluated and measured. Besides, the power flow
with the help of the poynting vector is discussed, and the link budget is evaluated for
implantable and off-body communications, respectively.