A Miniaturized Tunable Microstrip Antenna for Wireless Communications with Implanted Medical Devices

Abstract

In this paper, a miniaturized microstrip antenna design is presented for establishing wireless communications with implantable medical devices in the 402-405 MHz Medical Implant Communications Services (MICS). The Ansoft's High Frequency Structure Simulator (HFSS) and CST Microwave Studio were used to evaluate the antenna design. HFSS is based on the Finite Element Method (FEM) and Microwave Studio is based on the Finite Difference Time Domain (FDTD) technique. The results from both simulations are compared to validate results obtained from the two software packages. A varactor diode is added to allow tuning of the antenna. Size reduction techniques such as meandering, addition of a shorting pin, and the introduction of a capacitive plate were investigated to make the antenna size suitable for use with medical implants.

Design of a Novel Miniaturized Implantable PIFA for Biomedical Telemetry

“…Each of the radiating patches is printed on an 0.3 mm-thick Roger 3210 substrate (ε r =10.2 ). To ensure biocompatibility and robustness of the antenna, an 0.1mm-thick Roger 3210 superstrate layer covers the structure [5]. Both radiating patches are fed by means of a 50 Ohm coaxial cable with an inner radius of 0.2 mm (placed at d f = 2.9 mm from the centre of the ground plane), while a shorting pin with a radius of 0.2 mm connects the ground plane with the lower patch to achieve a further reduction in size (placed at d s = 3 mm from the centre of the ground plane) [15].…”

“…Finally, the performance of the communication link between the antenna implanted in the spherical head model and an exterior λ 0 /2 dipole receiver is examined. A reduced antenna size is achieved as compared to previous related works [4], [5], [8]- [12]. Simulations have been carried out using the finite-difference time-domain (FDTD) technique and the finite-elementmethod (FEM) [13].…”

“…In the most common scenario, the signals are wirelessly transmitted at the medical implant communication service (MICS) band of 402 405 − MHz, which is allocated for ultra-low-power active medical implants [3]. Miniaturization and biocompatibility of the antenna, bandwidth broadening to avoid frequency shift effects and optimization of the radiation performance are the main design considerations of the antenna [4], [5]. Furthermore, regulating the power delivered to the antenna to satisfy the specific absorption rate (SAR) limitations [6], [7] in the surrounding tissue in order to ensure patient safety is a critical issue.…”

A reflective practicum for transforming instructor's industrial skills into the teaching of radio frequency techniques and systems

“…The curriculum promotes research‐based educational strategies by involving undergraduate students in research activities early in their careers. Students developed sufficient skills and confidence to engage in professional presentations and publications in their senior year …”

“…Students developed sufficient skills and confidence to engage in professional presentations and publications in their senior year. [15,16] The rest of the paper is organized as follows. In Section 2, the instructional pedagogy is described.…”