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Energy harvesting coil for circularly polarized fields in magnetic resonance imaging [article]

Pavel Seregin, Oleg Burmistrov, Georgiy Solomakha, Egor Kretov, Nikita Olekhno, Alexey Slobozhanyuk
2021 arXiv   pre-print
One of the promising concepts in wireless MRI coils is energy harvesting that relies on converting the energy carried by the radio-frequency MRI field without the need for additional transmitters as in  ...  In this Article, we propose a compact harvesting coil design based on the combination of the loop and butterfly coils that allows energy harvesting of a circularly polarized field.  ...  ACKNOWLEDGMENTS This work was supported by the Russian Science Foundation (Project No.21-79-30038).  ... 
arXiv:2106.06886v1 fatcat:oj55kopkkzbyvk2m6wdcjtsyte

MRI Powered and Triggered Current Stimulator for Concurrent Stimulation and MRI [article]

Ranajay Mandal, Nishant B Babaria, Jiayue Cao, Kun-Han Lu, Zhongming Liu
2019 bioRxiv   pre-print
Results from testing it with phantoms and live animals in a 7 Tesla small-animal MRI system suggest that the device is able to harvest up to 72 (or 18) mW power during typical echo-planar imaging (or fast  ...  As a compact and standalone system, the plug-and-play device is suitable for animal research and merits further development for human applications.  ...  rate: 640T/m/s), a volume transmit and receive 1H RF coil (86 mm inner-diameter) and a surface receive-only 1H RF coil (10 mm inner-diameter).  ... 
doi:10.1101/715805 fatcat:on6osidshbd35m5lmgiaa5gicm

Table of Contents

2021 IEEE Transactions on Biomedical Circuits and Systems  
Novel Energy Harvesting Circuit for RF Surface Coils in the MRI System . . . . . . . . . . . . . A. Ganti, T. Wynn, and J.  ...  REGULAR PAPERS A Wearable Ultrasonic Neurostimulator -Part I: A 1D CMUT Phased Array System for Chronic Implantation in Small Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  ... 
doi:10.1109/tbcas.2021.3107969 fatcat:redovc52u5aevpfiunwv3gm63a

A Novel Expandable Catheter Wireless Amplified NMR Detector for MR Sensitivity Accessing the Kidney in Rodent Model

Roshan Timilsina, Chunqi Qian
2019 IEEE Transactions on Biomedical Circuits and Systems  
This paper demonstrates the enlarged effective range for MRI sensitivity enhancement with a deformable catheter MRI coils integrated with a wirelessly powered amplifier.  ...  The WAND is then mounted on a balloon catheter system for easy delivery inside confined orifice.  ...  Brad Roth for editing the manuscript. This work is supported in part by the National Institutes of Health (NIH) under Grant number R00EB016753.  ... 
doi:10.1109/tbcas.2018.2890657 pmid:30624224 pmcid:PMC6446567 fatcat:ml5jvfpvqfcm7k2iaawbh7kwia

MR Coagulation: A Novel Minimally Invasive Approach to Aneurysm Repair

Ouri Cohen, Ming Zhao, Erez Nevo, Jerome L. Ackerman
2017 Journal of Vascular and Interventional Radiology  
The distal end of the wire was laid on the patient table as an antenna to couple RF from the body coil, or connected to a separate tuned pickup coil.  ...  Purpose-To demonstrate a proof-of-concept of magnetic resonance coagulation (MRC), in which the MRI scanner-induced RF heating at the end of an intracatheter long wire heats and coagulates a protein solution  ...  Gilberto González for help with concept development. Clip art from Servier Medical Art image bank (www.servier.com) was used in Figure 1 .  ... 
doi:10.1016/j.jvir.2017.06.036 pmid:28802550 pmcid:PMC5657436 fatcat:d365yq3aonchdpguiuegzovodi

The 2021 MTT-S Graduate Student Fellowship Awards [Education News]

Giovanni Crupi, Roger Kaul, Changzhi Li, Wenquan Che, Rashaunda Henderson
2021 IEEE Microwave Magazine  
Project topic: RF coils based on high-permittivity materials with low losses and/or metamaterials for improved sensitivity magnetic resonance imaging (MRI).  ...  The artificial-dielectric resonator operates as a passive wireless structure that is electromagnetically coupled with the body transmit coil on a commercial 3-tesla clinical MRI system.  ... 
doi:10.1109/mmm.2021.3078043 fatcat:gftt54356fbt3c6uvs5jhpj2hi

Endourethral MRI

Harald H. Quick, Jean-Michel Serfaty, Harpreet K. Pannu, Rene Genadry, Christopher J. Yeung, Ergin Atalar
2001 Magnetic Resonance in Medicine  
To this end, two different radiofrequency (RF) receiver coil designs for an endourethral insertion have been developed: a single-loop coil and a phased array/quadrature coil.  ...  Both designs feature a flexible coil circuit, small loss tuning and matching directly at the coil, active decoupling, and the integration of a /4 coaxial choke to decrease unbalanced currents and limit  ...  The authors are grateful to Perry Karmarkar, M.S., of Surgi-Vision, Inc., for providing the flexible coil circuits and fabricating the prototype coil used in the in vivo pig experiments.  ... 
doi:10.1002/1522-2594(200101)45:1<138::aid-mrm1018>3.0.co;2-g pmid:11146495 fatcat:kkykrmca2ffrdhoyngf3cjl3km

Real-time magnetic resonance imaging–guided radiofrequency atrial ablation and visualization of lesion formation at 3 Tesla

Gaston R. Vergara, Sathya Vijayakumar, Eugene G. Kholmovski, Joshua J.E. Blauer, Mike A. Guttman, Christopher Gloschat, Gene Payne, Kamal Vij, Nazem W. Akoum, Marcos Daccarett, Christopher J. McGann, Rob S. MacLeod (+1 others)
2011 Heart Rhythm  
In this study, we report a novel 3-Tesla RT -RI based porcine RF ablation model and visualization of lesion formation in the atrium during RF energy delivery.  ...  OBJECTIVE The purpose of this study was to develop a 3-Tesla RT MRI-based catheter ablation and lesion visualization system. METHODS RF energy was delivered to six pigs under RT MRI guidance.  ...  In this study, we report a novel 3-Tesla RT MRI-guided catheter tracking system combined with a unique RT MRI sequence and a new T2-weighted (T2W) sequence, which have allowed us to successfully and safely  ... 
doi:10.1016/j.hrthm.2010.10.032 pmid:21034854 pmcid:PMC3118671 fatcat:kfg67lrbdjhxnkw5gwazihrsta

Soft subdermal implant capable of wireless battery charging and programmable controls for applications in optogenetics

Choong Yeon Kim, Min Jeong Ku, Raza Qazi, Hong Jae Nam, Jong Woo Park, Kum Seok Nam, Shane Oh, Inho Kang, Jae-Hyung Jang, Wha Young Kim, Jeong-Hoon Kim, Jae-Woong Jeong
2021 Nature Communications  
battery replacement or a special, bulky wireless power transfer system for continuous device operation, respectively.  ...  AbstractOptogenetics is a powerful technique that allows target-specific spatiotemporal manipulation of neuronal activity for dissection of neural circuits and therapeutic interventions.  ...  The power management circuit with a coil antenna primarily helps harvest wireless RF energy to form DC electrical charging currents for the LiPo battery (12 mAh, 0.3 g).  ... 
doi:10.1038/s41467-020-20803-y pmid:33483493 fatcat:x7vzzq6j5ffttpe46nhnjw4rj4

2019 Index IEEE Transactions on Microwave Theory and Techniques Vol. 67

2019 IEEE transactions on microwave theory and techniques  
., +, TMTT July 2019 2555-2568 A Dual-Mode RF Power Harvesting System With an On-Chip Coil in 180nm SOI CMOS for Millimeter-Sized Biomedical Implants.  ...  Khaleghi, A., +, TMTT March 2019 1093-1106 Dual-Mode RF Power Harvesting System With an On-Chip Coil in 180nm SOI CMOS for Millimeter-Sized Biomedical Implants.  ...  Power demand Design of Reconfigurable dB-Linear Variable-Gain Amplifier and Switchable-Order g m -C Filter in 65-nm CMOS Technology. Liu  ... 
doi:10.1109/tmtt.2019.2953035 fatcat:hyq2vngaxrcqlggu7bzcbzdyba

Europe and the Future for WPT : European Contributions to Wireless Power Transfer Technology

Cost Action IC1301 Team
2017 IEEE Microwave Magazine  
Machac was supported by the Czech Ministry of Education, Youth and Sports within the framework of the project LD14122 Electromagnetic Structures and Circuits for Wireless Power Transmission.  ...  Acknowledgments The work presented in this paper was accomplished within the European Union COST Action IC1301. The work of J. Kracek, M. Svanda, M. Mazanek, and J.  ...  The coil arrangement in the MFIPT system from [57] .  ... 
doi:10.1109/mmm.2017.2680078 fatcat:q3yv6fhihvflljadzar7qzxre4

Program

2021 2021 IEEE International Conference on RFID (RFID)  
energy dissipation compared to the traditional tracking systems.  ...  We present a real-time multi-user UHF RFID tomographic localization system that employs a novel signal processing pipeline that uses communication channel parameters such as RSSI, RF Phase, and Read Rate  ...  S8: Workshop on Wireless Energy Harvesting Design and Experimentation of a Novel Five Coil Asymmetric Magnetic Resonance Wireless Power Transfer System Rafael R Figueroa III, Allen G Morinec, Jr, Ethan  ... 
doi:10.1109/rfid52461.2021.9444380 fatcat:4g4yxtwpszh7robhdrzh6blmxa

Enabling Seamless Wireless Power Delivery in Dynamic Environments

Alanson P. Sample, Benjamin H. Waters, Scott T. Wisdom, Joshua R. Smith
2013 Proceedings of the IEEE  
However, unpredictable loads rapidly change system operating points, and changes in position disrupt system efficiency, which affects the ultimate usability of these systems.  ...  Recent work using magnetically coupled resonators (MCRs) for wireless power delivery has shown a promising intersection between range (on the order of a meter), efficiency (over 80%), and delivered power  ...  Low Q limits the amount of energy that can be stored in the coils and thus reduces the magnetic flux density for a given location.  ... 
doi:10.1109/jproc.2013.2252453 fatcat:66c3aaoecncl7oo5lmaxmvbfqq

Table of contents

2019 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)  
Flexible Distributed Capacitance Coil Simulation in MR Imaging . . . . . . . . . . . . . . . . 2062 A Novel Mixed Integer Programming Scheme for Passive Shimming in MRI . . . . . . . . . . . . . .  ...  Novel Device Model Validation System for 1.5 T and 3 T MRI Safety Assessment . . . . . . . . . . . . . . . . . . . 1283 On the Diagnosis of Incipient Faults in Transmission Lines Using a Projection  ... 
doi:10.1109/piers-fall48861.2019.9021769 fatcat:tkvlcifbifgolbr3u3kt5j3jra

Sensitivity Enhancement of an Inductively Coupled Local Detector Using a HEMT-Based Current Amplifier

Chunqi Qian, Qi Duan, Steve Dodd, Alan Koretsky, Joe Murphy-Boesch
2015 Magnetic Resonance in Medicine  
Methods- The resonant detection coil is connected in parallel with the gate of a HEMT transistor without impedance matching.  ...  This amplifier enables efficient signal transmission between customized user coils and commercial clinical coils, without the need for a specialized signal interface.  ...  This research was supported by the Intramural Research Program of the NINDS at NIH and R00EB016753.  ... 
doi:10.1002/mrm.25850 pmid:26192998 pmcid:PMC4720591 fatcat:hnmgau5zpjfwpbgz3vi3cjv2iy
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