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Korea Multimedia Society (한국멀티미디어학회)
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Analysis of the Bird-cage Receiver Coil of a MRI System Employing a Equivalent Circuit Model Based on a Transmission Matrix

전송행렬 기반 등가 회로 모델을 이용한 자기공명영상 장치용 새장형 수신 코일 해석

  • Kim, Hyun Deok (School of Electronics Engineering, Kyungpook National University)
  • Received : 2017.06.07
  • Accepted : 2017.07.06
  • Published : 2017.07.31
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Abstract

A novel analytic solution has been derived for the bird-cage receiver coil of a magnetic resonance imaging (MRI) system, which is widely used in 3-dimensional medical imaging, by transforming the coil into an equivalent circuit model by using a transmission matrix-based circuit analysis. The bird-cage coil composed of N legs is divided into a cell for which input impedance is to be analyzed and the remaining N-1 cells, and then a transmission matrix corresponding to the N-1 cells is converted into a circuit to transform the 3-dimensional bird-cage coil into the 2-dimensional equivalent circuit model, which is suitable to derive the analytic solution for the input impedance. The proposed method derives directly the analytic solution for the input impedance at an arbitrary point of the coil unlike the conventional analytic solution of a bird-cage coil, so that it can be used not only for resonance frequency calculations but also for various coil characteristics analyses. Since the analytic solution agreed well with the results of computational simulations, it can be useful for the impedance matching of a coil and the analysis and the design of a multi-tune bird-cage coil.

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References

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