Abstract
The ultra-high field magnetic resonance imaging (MRI) system has become a key focus of clinical and scientific research due to its remarkable sensitivity and resolution. However, achieving whole-body MRI at ultra-high field strengths necessitates enhanced power-drive capability in order to optimize the excitation of radio frequency (RF) coils. To avoid significant signal transmission losses, it is necessary to ensure that the RF transmission chain has a high transmission efficiency. An 8 kW non-magnetic RF power amplifier (RFPA) has been proposed for 5T whole-body magnetic resonance imaging. The proposed non-magnetic structure allows the RF power amplifier to be placed directly in the scanning room, thereby reducing transmission distance and enhancing transmission efficiency. The multi-stage amplification structure based on high power MOSFETs employed a magnetic-planar balun and a lumped-distributed power combiner design to attain a peak output power of 8 kW (69 dBm). Additionally, The nonlinearity correction of gain and status monitoring of the amplifier was facilitated by incorporating a dual directional coupler and feedback control loop design.
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Acknowledgments
This work was funded partly by National Key Research and Development Program of China (2021YFE0204400),National Natural Science Foundation of China (816279 01), National Key Research and Development Program of China (2022YFA1004200), Key Laboratory Project of Guangdong Province, China (2020B1212060051), Funding Program of Shenzhen, China (RCYX20200714114735123), The Chinese Academy of Sciences Youth Innovation Promotion Association funded project (Y2021098), High-end medical imaging key technology and core components innovation team funded project, China (JSGGKQTD20210831174329010).
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Wang, J., Liu, S., Chen, J., Rong, X., Yang, X., Li, Y. (2024). 8kW Non-magnetic RF Power Amplifier of 5T Human Body Magnetic Resonance. In: Yang, Q., Li, Z., Luo, A. (eds) The Proceedings of the 18th Annual Conference of China Electrotechnical Society. ACCES 2023. Lecture Notes in Electrical Engineering, vol 1179. Springer, Singapore. https://doi.org/10.1007/978-981-97-1428-5_15
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DOI: https://doi.org/10.1007/978-981-97-1428-5_15
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