Electrically Small Spiral PIFA for Deep Implantable Devices

Abstract

In this paper, a miniaturized implantable circularly polarized spiral Planar Inverted-F Antenna (SPIFA) in the UHF (600-800 MHz) band is presented. This antenna is intended for deep implantable devices such as leadless pacemakers and deep brain stimulation (DBS), which facilitates the reception of RF power from an external transmitter. The antenna is electrically small, with a volume of π× 5 mm × 5 mm × 3.2 mm and a diameter of 0.022λ. The performance of the proposed antenna in terms of reflection coefficient, realized gain and axial ratio are assessed when accounting for the effects of operating in different types of human body tissues, different biocompatible materials and different thicknesses and depths of the implanted antenna. Finally, the antenna is prototyped and measured in free space, a phantom model, in a cow's fat and muscle tissues to validate the simulation results, indicating good agreements. A realized gain around -20 dBm is achieved when operating in 50 mm depth in cow's muscle tissue while having electrically very small dimensions compared to implantable antennas reported in the literature.

Meta-Wearable Antennas—A Review of Metamaterial Based Antennas in Wireless Body Area Networks

“…The use of metamaterials has been hugely successful in adapting conventional antenna designs into a Figure 1. A Wireless Body Area Network (WBAN) and its applications [1,[8][9][10][11][12][13][14][15][16].…”

“…Through WBAN, communication and data synchronization can take place to complete the other communication networks, such as wireless sensor networks and mobile communication networks [ 1 , 2 , 6 , 7 ]. An important application of WBAN is in healthcare, where the body area network can transmit physiological information obtained from patients through various physiological sensors, such as blood pressure, blood sugar concentration, temperature, weight, and heartbeat [ 1 , 8 , 9 , 10 ] to the hospital’s medical monitoring equipment or the user’s personal mobile terminal [ 11 ]. In entertainment, a personal media device with high speed communication capability will enable augmented/virtual/mixed reality interaction with users, and wirelessly communicate with a device such as glasses [ 12 ] or headset [ 13 ].…”

Design of UWB Wearable Conformal Antenna Based on Jean Material

“…In military applications, wearable antennas can provide personal positioning and mobile communication through helmets [4,5]. In healthcare, wearable antennas can monitor physiological information, such as blood pressure, blood glucose concentration, temperature, weight, and heartbeat [6][7][8]. These applications face limitations due to electromagnetic coupling between the human body and the antenna, changing physical deformations, highly variable operating environments, and manufacturing processes [9][10][11].…”

Design of Conformal Spiral Dual-Band Antenna for Wireless Capsule System

“…Due to the limitations of space in implantable devices, how to maintain antenna dual-band and broadband while reducing the space occupied by the antenna is the top priority. Some miniaturization techniques, such as high dielectric constant substrate [14], [15], meandered line [16], spiral line [10], opening slot [17], and adding shorting pins [18], as well as stacked antennas [19], are used to reduce the space. However, these miniaturization technologies usually bring difficulties to the antenna design and production process and still occupy the limited space.…”