Chinese Journal of Magnetic Resonance >
A Design of Circularly Polarized Coil for Low-field Nuclear Magnetic Resonance Spectrometers
Received date: 2025-03-17
Online published: 2025-04-07
Signal-to-noise ratio (SNR) is a key parameter governing signal quality in benchtop MRS spectrometers, where quadrature circularly polarized coils offer an effective means to enhance SNR. However, the confined space within the compact magnets of desktop systems poses challenges for implementing such coils—a strategy previously unattempted in this domain. Leveraging a self-developed desktop MRS platform, this study designed and fabricated a flexible printed circuit-based transceiver-integrated circularly polarized coil system, comprising orthogonally arranged saddle and Helmholtz coils. The coil geometry was optimized through Ansys Maxwell simulations, and experimental validation using CuSO₄ solution demonstrated SNR improvements of 28.78% and 29.21% over single-channel saddle and Helmholtz coils, respectively, alongside a 37.5% reduction in reflected power. These results confirm the viability of circularly polarized coils for advancing desktop MRS probe performance.
TANG Shihao , YANG Jinyu , XU Yajie , WANG Ya , PENG Bowen , GAO Yuhao , YANG Xiaodong . A Design of Circularly Polarized Coil for Low-field Nuclear Magnetic Resonance Spectrometers[J]. Chinese Journal of Magnetic Resonance, 2025 , 42(3) : 308 -320 . DOI: 10.11938/cjmr20253150
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