Modeling and Characterization of Capacitive Elements With Tissue as Dielectric Material for Wireless Powering of Neural Implants

  title={Modeling and Characterization of Capacitive Elements With Tissue as Dielectric Material for Wireless Powering of Neural Implants},
  author={Reza Erfani and Fatemeh Marefat and Amir Masoud Sodagar and Pedram Mohseni},
  journal={IEEE Transactions on Neural Systems and Rehabilitation Engineering},
This paper reports on the modeling and characterization of capacitive elements with tissue as the dielectric material, representing the core building block of a capacitive link for wireless power transfer to neural implants. Each capacitive element consists of two parallel plates that are aligned around the tissue layer and incorporate a grounded, guarded, capacitive pad to mitigate the adverse effect of stray capacitances and shield the plates from external interfering electric fields. The… 
Biosafety Considerations of a Capacitive Link for Wireless Power Transfer to Biomedical Implants
This work specifically focuses on investigating the optimal range of link operation frequency, f<inf>op</inf>, that maximizes the power transfer efficiency (PTE) and power delivered to the load (PDL) parameters under biosafety constraints imposed by specific absorption rate and electric-field strength in living tissue.
On the Non-idealities of a Capacitive Link for Wireless Power Transfer to Biomedical Implants
The study shows that plate misalignment (causing reduction in parallel plate overlap area) and skin tissue contraction (while muscle grows) are the most detrimental individual factors to the link performance.
Auto-Resonant Tuning for Capacitive Power and Data Telemetry Using Flexible Patches
Flexible, conformable, and biocompatible patches are adopted with an automatic resonant frequency calibration technique for the first time and a reliable power and data transfer scheme for biomedical implants through a resonant capacitive link is proposed and demonstrated.
Powering electronic implants by high frequency volume conduction: in human validation
It is demonstrated for the first time in humans that innocuous and imperceptible HF current bursts that flow through the tissues by volume conduction can be used to wirelessly power threadlike eMIs, overcoming the limitations of existing WPT methods in terms of minimal invasiveness and usability.
Improving Power Delivery of CPT for Biomedical Implants by Using Conjugate Impedance Matching
The conjugate impedance matching method is applied to the CPT system for the first time, different from the existing simple impedance matching by only using inductors.
Bioelectronic systems enabled by wireless electromagnetic power transfer
The work presented in this thesis demonstrates that by extending wireless powering schemes from the well known inductive coil to include capacitive and radiative power transfer, capacitive power and data transfer is viable for stent-based biomedical implants.
Study of mm-sized Coil to Coil Backscatter Based Communication Link
For the first time, the feasibility of local communication between mm-sized coils is demonstrated using backscattering technique which promises to reduce the requirement on the uplink bandwidth between the external device and the implants.
Antenna array design on flexible substrate for wireless power transfer
In this work, a microstrip antenna array for wireless power transfer (WPT) application is reported. The proposed 4 × 4 antenna array operating at 16 GHz is designed using a flexible Kapton polyimide
Long Distance Power Transfer Technique: A Review
This paper is focused on the vigorous beam forming issues for the multi-radio wire remote telecom framework with synchronous data and power transmission under the supposition of flawed station state data at the transmitter following the most pessimistic scenario deterministic model.
A 1–10-MHz Frequency-Aware CMOS Active Rectifier With Dual-Loop Adaptive Delay Compensation and >230-mW Output Power for Capacitively Powered Biomedical Implants
A novel CMOS active rectifier for the emerging modality of capacitive wireless power transfer to biomedical implants with high power budgets is presented, utilizing dual-loop adaptive delay compensation to provide both high resolution and high dynamic range in switched-offset currents of comparators.


Modeling and Experimental Validation of a Capacitive Link for Wireless Power Transfer to Biomedical Implants
The modeling and experimental validation of a capacitive link as an emerging strategy for wireless power transfer to biomedical implants and in very good agreement with simulation results from the related circuit model is reported.
Transcutaneous capacitive wireless power transfer (C-WPT) for biomedical implants
A transcutaneous capacitive wireless power transfer strategy for biomedical implants based upon a series resonant converter in which the tank capacitors are replaced with a capacitive link comprising two pairs of coated parallel plates aligned around the tissue as the dielectric material is reported on.
Wireless Power Delivery to Flexible Subcutaneous Implants Using Capacitive Coupling
The studies validate the NCC method as a safe wireless powering scheme, which can be used as an alternative to the near-field resonant inductive coupling method, for chronic use in subcutaneous implants.
Modeling of a capacitive link for data telemetry to biomedical implants
This paper presents modeling of a capacitive link for wireless data transfer to implantable biomedical microsystems. Based on the proposed model, voltage transfer ratio of the link is calculated, and
Wireless Power Transfer Strategies for Implantable Bioelectronics
This review presents the theory, link design, and challenges, along with their probable solutions for the traditional near-field resonant inductively coupled WPT, capacitively coupled short-ranged W PT, and more recently developed ultrasonic, mid-field, and far-field coupled W PT technologies for implantable applications.
A Biosafety Comparison Between Capacitive and Inductive Coupling in Biomedical Implants
This letter investigates the link efficiencies and ensuing biohazards when capacitive versus inductive coupling is used to power biomedical implants electromagnetically. Electromagnetic simulations
Capacitive power transfer for contactless charging
The simplicity and low cost of capacitive interfaces makes them very attractive for wireless charging stations. Major benefits include low electromagnetic radiation and the amenability of combined
A Hybrid Inductive-Ultrasonic Link for Wireless Power Transmission to Millimeter-Sized Biomedical Implants
  • Miao Meng, M. Kiani
  • Computer Science
    IEEE Transactions on Circuits and Systems II: Express Briefs
  • 2017
A hybrid inductive-ultrasonic WPT link for powering mm-sized implants that utilizes two cascaded co-optimized inductive and ultrasonic links for WPT through bone/air and tissue, respectively is presented.
A Wireless Implantable Multichannel Microstimulating System-on-a-Chip With Modular Architecture
A 64-site wireless current microstimulator chip (Interestim-2B) and a prototype implant based on the same chip have been developed for neural prosthetic applications, which has site potential measurement and in situ site impedance measurement capabilities, which help its users indicate defective sites or characteristic shifts in chronic stimulations.
Capacitive Power Transfer Through a Conformal Bumper for Electric Vehicle Charging
  • J. Dai, D. Ludois
  • Engineering
    IEEE Journal of Emerging and Selected Topics in Power Electronics
  • 2016
Wireless power transfer (WPT) is emerging as a practical means for electric vehicle (EV) charging. Of the most common approaches to WPT, inductive coupling, and capacitive coupling, capacitive power