Anil Kumar RamRakhyani

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Two-coil based inductive coupling is a commonly used technique for wireless power and data transfer for biomedical implants. Because the source and load resistances are finite, two-coil systems generally achieve a relatively low power transfer efficiency. A novel multi-coil technique (using more than two coils) for wireless power and data transfer is(More)
Inductive coupling-based wireless power transfer (WPT) is commonly used for near-field power and data transfer to implanted electronics. Some implanted coils undergo relative motion during device operation causing variation in magnetic coupling from their normal position. To ensure stable power transfer efficiency and frequency bandwidth, these WPT systems(More)
Functional electrical stimulation is the current gold standard for stimulating neuronal interfaces for functional neuromuscular and cortical applications, but it is not without its drawbacks. One such fault is the need to have direct electrical contact with the nerve tissue, and any side effects this causes. Functional magnetic stimulation, which works(More)
Wireless power transfer using resonant inductive coupling has been employed in a number of applications, including wireless charging of electronic devices and powering of implanted biomedical devices. In these applications, power is transferred over short distances, which are much smaller (~ λ/100) than the wavelength of operation. In such systems,(More)
There has been recurring interest in using magnetic neural stimulation for implantable localized stimulation. However, the large stimulation voltages and energies necessary to evoke neuronal activity have tempered this interest. To investigate the potential of magnetic stimulation as a viable methodology and to provide the ability to investigate novel coil(More)
An extremely compact and low-frequency metamaterial design is presented in the following work. A ferrite loaded solenoid with a size on the order of 1/10000 of the wavelength of operation is used as the unit cell of the proposed metamaterial. This unit cell allows for the construction of a 77 unit-cell sample with dimensions of 6 cm × 6 cm × 2(More)
A popular technique for wireless power transfer, particularly in biomedical implants, is inductive coupling. One of the first applications of this technique in the biomedical field was to supply power to an artificial heart. Since then, it has commonly been used in implantable devices. For short-range wireless power transfer systems, working on inductive(More)
Summary form only given. Neural stimulators are the key building blocks of current neuroprosthetic systems, such as cochlear and retinal implants. Due to direct current injections and foreign body reactions, conventional current passing electrodes suffer from reduced performance and reduced lifetimes. However, magnetic fields can be used as an alternative(More)
The need to correctly predict the voltage across terminals of mm-sized coils, with ferrite core, to be employed for magnetic stimulation of the peripheral neural system is the motivation for this work. In such applications, which rely on a capacitive discharge on the coil to realise a transient voltage curve of duration and strength suitable for neural(More)
Implantable medical devices are used to supplement, monitor, or replace physiological function for a variety of medical conditions. In this article we highlight a set of topics that we believe could eventually be instrumental in bringing the next generation of implantable devices to existence. These include multi-scale numerical modeling and simulation,(More)