A Broadband Flexible Implantable Loop Antenna With Complementary Split Ring Resonators

Author

Alrawashdeh, Rula S. ; Yi Huang ; Kod, Muayad ; Abu Bakar Sajak, Aznida

Author_Institution

Dept. of Electr. Eng. & Electron., Univ. of Liverpool, Liverpool, UK

Volume

14

fYear

2015

fDate

7/7/1905 12:00:00 AM

Firstpage

1506

Lastpage

1509

Abstract

In this letter, a novel flexible implantable loop antenna with complementary split ring resonators (CSRRs) is proposed and designed for biomedical telemetric applications. The antenna has a very wide bandwidth to cover the Medical Device Radiocommunications service (MedRadio 401-406 MHz) and Industrial, Scientific and Medical (ISM 433.1-434.8, 868.0-868.8, 902.8-928.0 MHz and 2.45 GHz) bands which support the functions of wireless data transmission, wireless power transfer and saving (wakeup receiver). It is optimized over a two-step design process for cylindrical implants for a robust communication over 2 m. The CSRRs are introduced to reduce the absorbed power inside the body and improve the antenna impedance matching. This results in a larger radiation efficiency, gain and transmission coefficient (over 2 dB in comparison with the structure without the CSRRs). The specific absorption rate (SAR) is also decreased significantly. Measurements in a pork phantom are conducted and a good agreement with the simulation results is demonstrated. This novel antenna could be an excellent candidate for a range of implantable applications.

Keywords

UHF antennas; UHF resonators; antenna radiation patterns; biomedical telemetry; broadband antennas; impedance matching; loop antennas; CSRR; ISM bands; MedRadio; SAR; antenna impedance matching; biomedical telemetric applications; complementary split ring resonators; cylindrical implants; distance 2 m; flexible implantable loop antenna; frequency 2.45 GHz; frequency 401 MHz to 406 MHz; frequency 433.1 MHz to 434.8 MHz; frequency 868 MHz to 868.8 MHz; frequency 902.8 MHz to 928 MHz; industrial scientific and medical bands; medical device radiocommunications service; pork phantom; radiation efficiency; specific absorption rate; transmission coefficient; wakeup receiver; wireless data transmission; wireless power transfer; Antenna measurements; Broadband antennas; Gain; Implants; Transmitting antennas; ISM band antenna; Implantable antenna; MedRadio band antenna; specific absorption rate;

fLanguage

English

Journal_Title

Antennas and Wireless Propagation Letters, IEEE

Publisher

ieee

ISSN

1536-1225

Type

jour

DOI

10.1109/LAWP.2015.2403952

Filename

7042255