title: Implanted miniaturized antenna for brain computer interface applications: analysis and design.
abstract: Implantable Brain Computer Interfaces (BCIs) are designed to provide real-time control signals for prosthetic devices, study brain function, and/or restore sensory information lost as a result of injury or disease. Using Radio Frequency (RF) to wirelessly power a BCI could widely extend the number of applications and increase chronic in-vivo viability. However, due to the limited size and the electromagnetic loss of human brain tissues, implanted miniaturized antennas suffer low radiation efficiency. This work presents simulations, analysis and designs of implanted antennas for a wireless implantable RF-powered brain computer interface application. The results show that thin (on the order of 100 micrometers thickness) biocompatible insulating layers can significantly impact the antenna performance. The proper selection of the dielectric properties of the biocompatible insulating layers and the implantation position inside human brain tissues can facilitate efficient RF power reception by the implanted antenna. While the results show that the effects of the human head shape on implanted antenna performance is somewhat negligible, the constitutive properties of the brain tissues surrounding the implanted antenna can significantly impact the electrical characteristics (input impedance, and operational frequency) of the implanted antenna. Three miniaturized antenna designs are simulated and demonstrate that maximum RF power of up to 1.8 milli-Watts can be received at 2 GHz when the antenna implanted around the dura, without violating the Specific Absorption Rate (SAR) limits.
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.
authors: Yujuan
authors: Y
authors: Zhao
authors: Behavioral and Brain Sciences, Erik Jonsson School of Engineering, University of Texas Dallas, Richardson, Texas, United States of America.
authors: Robert L
authors: RL
authors: Rennaker
authors: School of Electrical and Computer Engineering, Oklahoma State University, Stillwater, Oklahoma, United States of America.
authors: Chris
authors: C
authors: Hutchens
authors: Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America; Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America.
authors: Tamer S
authors: TS
authors: Ibrahim
mesh_terms: D062207:Brain-Computer Interfaces; D006801:Humans; D020007:Implants, Experimental; D019047:Phantoms, Imaging; D059015:Wireless Technology