A Pseudo-Normal-Mode Helical Antenna for Use With Deeply Implanted Wireless Sensors

• Published in: IEEE transactions on antennas and propagation 2012-02, Vol.60 (2), p.1135-1139
• Main Authors: Murphy, O. H., McLeod, C. N., Navaratnarajah, M., Yacoub, M., Toumazou, C.
• Format: Article
• Language: English
• Subjects: Antenna measurements; Antennas; Applied classical electromagnetism; Applied sciences; Biomedical applications of electromagnetic (EM) radiation; biomedical telemetry; Dipole antennas; Electromagnetic wave propagation, radiowave propagation; Electromagnetism; electron and ion optics; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Helical antennas; implantable biomedical devices; In vitro; In vivo; Insulation; Physics; Radiocommunications; Services and terminals of telecommunications; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Telemetry. Remote supervision. Telewarning. Remote control
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2011.2173106

A pseudo-normal-mode helical antenna as part of a deeply implanted wireless sensor was designed. Justification for using this type of antenna along with simulation, in vitro and in vivo experimental results are presented in this communication. The circumference of the helical coil is 0.43λ ib (wavelength in-body) and its height is 0.23λ ib which includes substantial insulation. While losses from such a deeply implanted antenna are inevitable, the work presented here shows accurate frequency tuning can be achieved prior to implantation. The relative size, safety of use and results presented here make this pseudo-normal-mode helical antenna an excellent candidate for use with deeply implanted wireless sensors.