November 2015

Byunghun won the Silver Award in the highly competitive “The 11th Samsung Electro-Mechanics Best Paper Awards”. The title of his paper was “A Multi-Cycle Q-Modulation Technique for Wirelessly-Powered Biomedical Implants.” You may find more information here.

October 2015

Yaoyao, Zheyuan, and Abdollah won the Best Live Demo Award at the 2015 IEEE Biomedical Circuits and Systems Conference. Their demo was titled: “Live Demonstration: A Smart Homecage System with Behavior Analysis and Closed-Loop Optogenetic Stimulation Capabilities”. You may find more information here.

August 2015

GT-Bionics lab will participate in the 2015 IEEE Biomedical Circuits and Systems Conference (BioCAS'15) with 6 papers. BioCAS serves as a premier international forum for presenting the interdisciplinary research and development at the crossroads of medicine, life sciences, physical sciences and engineering that will shape tomorrow's medical devices and healthcare systems.

July 2015

Congratulations to Dr. Sarah Ostadabbas for accepting a faculty position at Northeastern University. We at the GT Bionics lab look forward to you making us all proud. We'll miss you!

March 2015

Dr. Ghovanloo was named an IEEE Circuits and Systems Society Distinguished Lecturer for 2015-2016 term. The topics on which he will lecture are "Implantable and Wearable Microelectronic Devices to Improve Quality of Life for People with Disabilities" and "Efficient Power and Wideband Data Transmission in Near Field."

November 2014

Tongue Drive featured in US NEWS and World Report: Wearable Tech for People With Disabilities.

Multi-Carrier Wireless Link for Implantable Biomedical Devices

An inductive link between two magnetically-coupled coils that constitute a transformer is the most common method to wirelessly transmit power and data to implantable biomedical devices that have relatively high power consumption such as neuromuscular stimulators, cochlear implants, and visual prostheses. Neuroprostheses that substitute sensory functions also need sizeable amounts of real-time data to interface with a large number of neurons by means of tens to hundreds of stimulating sites that are driven simultaneously through multiple parallel channels. The wireless link should be robust enough not to be affected by patient’s motion artifacts or minor coils misalignments. A back telemetry link is also needed for implant power regulation, stimulating sites impedance measurement, and recording the neural response for accurate electrode placement and stimulation parameter adjustments.

Therefore, high power transmission efficiency, high data transmission bandwidth, magnetic coupling insensitivity, and back telemetry are the major wireless link requirements in the design and implementation of high performance implantable biomedical devices. While these requirements are individually attainable, they have not been achieved concurrently with traditional techniques. The reason is that there are conflicting constraints involved in achieving high performance in two or more of the above system requirements.

The wireless link operating frequency, also known as the carrier frequency, is one of the most important parameters of an inductive link, which affects all other system specifications. Traditionally, a single carrier frequency has been used for (1) inductive power transmission, (2) forward data transmission from outside to the implanted device, and (3) back telemetry from the implanted device outward. In this research we are using three carrier signals at three different frequencies and amplitude levels: (a) low-frequency high-amplitude (fP < 1MHz) for power transmission, (b) medium-frequency medium-amplitude (fFD ~ 50MHz) for forward data link, and (c) high-frequency low-amplitude (fBT > 400MHz) for back telemetry. These frequencies are optimal for the above three major functions and we can effectively isolate many of the competing parameters in the design of a wireless link. Therefore, we expect to achieve a high performance in all of the aforementioned system requirements.

The research presented here is aimed at developing a robust, power-efficient, wideband, bidirectional wireless link using multiple carrier frequencies. The new link will be utilized in development of a prototype neuroprosthetic testbed for a visual prosthesis. The prototype neuroprosthesis will be tested in vitro to evaluate the multi-frequency wireless link performance in the tissue environment. Then it will be used in short term in vivo experiments.

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