A Novel Energy Harvesting Circuit for RF Surface Coils in the MRI System

Ganti, Aasrith; Wynn, Tracy; Lin, Jenshan

doi:10.1109/tbcas.2021.3103431

Cited by 4 publications

(3 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As an alternative, it has been suggested to harvest energy from the powerful radiofrequency (RF) pulses involved in MRI in the first place. [7][8][9][10] Equally wireless, this completely parasitic approach avoids the need for additional power transmission and the hardware involved. It has been reported to harvest average power in the order of 100 mW from standard medical imaging sequences, using receiver form factors of just a few centimeters.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Stealth RF energy harvesting in MRI using selective shielding

Bjorkqvist,

Pruessmann

2024

Magnetic Resonance in Med

View full text Add to dashboard Cite

PurposeTo utilize the transmit radiofrequency (RF) field in MRI as a power source, near or within the field of view but without affecting image quality or safety.MethodsPower harvesting is performed by RF induction in a resonant coil. Resulting RF field distortion in the subject is canceled by a selective shield that couples to the harvester while being transparent to the RF transmitter. Such shielding is designed with the help of electromagnetic simulation. A shielded harvester of 3 cm diameter is implemented, assessed on the bench, and tested in a 3T MRI system, recording power yield during typical scans.ResultsThe concept of selective shielding is confirmed by simulation. Bench tests show effective power harvesting in the presence of the shield. In the MRI system, it is confirmed that selective shielding virtually eliminates RF perturbation. In scans with the harvester immediately adjacent to a phantom, up to 100 mW of average power are harvested without affecting image quality.ConclusionSelective shielding enables stealthy RF harvesting which can be used to supply wireless power to on‐body devices during MRI.

show abstract

Section: Introductionmentioning

confidence: 99%

“…As an alternative, it has been suggested to harvest energy from the powerful radiofrequency (RF) pulses involved in MRI in the first place 7–10 . Equally wireless, this completely parasitic approach avoids the need for additional power transmission and the hardware involved.…”

Section: Introductionmentioning

confidence: 99%

Stealth RF energy harvesting in MRI using selective shielding

Bjorkqvist,

Pruessmann

2024

Magnetic Resonance in Med

View full text Add to dashboard Cite

show abstract

“…All of these wired connections require complex cable routing inside the scanner with expensive RF cables, filters, and baluns to maintain the MR image quality (Peterson et al 2003, Fujita et al 2013. These cable assemblies can add significant weight and bulk to the coil array, which increase patient setup time and may cause patient discomfort, and they must be carefully placed around the patient to avoid burn risks (Dempsey et al 2001, Ganti et al 2021. To address these limitations, a previous study has proposed to split a typical RF coil array cable assembly into two separate cable assemblies and to use inductivelycoupled RF 'sniffer' coils to transfer the image data between them (Bulumulla et al 2015).…”

Section: Introductionmentioning

confidence: 99%

Numerical simulations of an integrated radio-frequency/wireless coil design for simultaneous acquisition and wireless transfer of magnetic resonance imaging data

Overson,

Bresticker,

Willey

et al. 2023

Phys. Med. Biol.

View full text Add to dashboard Cite

Objective: A novel MRI radio-frequency coil design, termed an integrated RF/wireless (iRFW) coil design, can simultaneously perform MRI signal reception and far-field wireless data transfer with the same coil conductors between the coil in the scanner bore and an access point (AP) on the scanner room wall. The objective of this work is to optimize the design inside the scanner bore to provide a link budget between the coil and the AP for the wireless transmission of MRI data. Approach: Electromagnetic simulations were performed at the Larmor frequency of a 3T scanner and in a WiFi wireless communication band to optimize the radius and position of an iRFW coil located near the head of a human model inside the scanner bore, which were validated by performing both imaging and wireless experiments.Main Results: The simulated iRFW coil with a 40-mm radius positioned near the model forehead provided: a signal-to-noise ratio (SNR) comparable to that of a traditional RF coil with the same radius and position, a power absorbed by the human model within regulatory limits, and a gain pattern in the scanner bore resulting in a link budget of 51.1 dB between the coil and an AP located behind the scanner 3 m from the isocenter, which would be sufficient to wirelessly transfer MRI data acquired with a 16-channel coil array.Significance: The MRI coil array cable assembly connected to the scanner increases patient setup time, can present a burn risk to patients and is an obstacle to the development of lightweight, flexible, or wearable coil arrays that provide an improved coil sensitivity. Significantly, the RF coaxial cables and corresponding receive chain electronics can be removed from within the scanner by integrating the iRFW coil design into an array for the wireless transmission of MRI data outside of the bore.

show abstract