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Magnetic Resonance Materials in Physics, Biology and Medicine

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01-12-2019 | Magnetic Resonance Imaging | Research Article

A high duty-cycle, multi-channel, power amplifier for high-resolution radiofrequency encoded magnetic resonance imaging

Authors: Aaron R. Purchase, Tadeusz Pałasz, Hongwei Sun, Jonathan C. Sharp, Boguslaw Tomanek

Published in: Magnetic Resonance Materials in Physics, Biology and Medicine | Issue 6/2019

Abstract

Objective

A radiofrequency (RF) power amplifier is an essential component of any magnetic resonance imaging (MRI) system. Unfortunately, no commercial amplifier exists to fulfill the needs of the transmit array spatial encoding (TRASE) MRI technique, requiring high duty cycle, high RF output power and independently controlled multi-channel capability. Thus, an RF amplifier for TRASE MRI is needed.

Materials and methods

A dual-channel RF power amplifier dedicated for TRASE at 0.22 T (9.27 MHz) was designed and constructed using commercially available components. The amplifier was tested on the bench and used a 0.22 T MRI system with a twisted solenoid and saddle RF coil combination capable of a single-axis TRASE.

Results

The amplifier is capable of sequential, dual-channel operation up to 50% duty cycle, 1 kW peak output and highly stable 100 μs RF pulse trains. High spatial resolution one-dimensional TRASE was obtained with the power amplifier to demonstrate its capability.

Conclusion

The constructed amplifier is the first prototype that meets the requirements of TRASE rectifying limitations of duty cycle and timing presented by commercial RF amplifiers. The amplifier makes possible future high resolution in vivo TRASE MRI.

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Title: A high duty-cycle, multi-channel, power amplifier for high-resolution radiofrequency encoded magnetic resonance imaging
Authors: Aaron R. Purchase
Tadeusz Pałasz
Hongwei Sun
Jonathan C. Sharp
Boguslaw Tomanek
Publication date: 01-12-2019
Publisher: Springer International Publishing
Keywords: Magnetic Resonance Imaging
Magnetic Resonance Imaging
Published in: Magnetic Resonance Materials in Physics, Biology and Medicine / Issue 6/2019
Print ISSN: 0968-5243
Electronic ISSN: 1352-8661
DOI: https://doi.org/10.1007/s10334-019-00763-1

Keynote webinar | Spotlight on sleep in brain health

Springer Medicine

A high duty-cycle, multi-channel, power amplifier for high-resolution radiofrequency encoded magnetic resonance imaging

Abstract

Objective

Materials and methods

Results

Conclusion

Keynote webinar | Spotlight on sleep in brain health

Springer Medicine

Abstract

Objective

Materials and methods

Results

Conclusion

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