A Flexible Rectangular PCB Coil to Excite Uniform Magnetic Field in Nuclear Magnetic Resonance Spectroscopy: Design, Optimization and Implementation

AbstractIn this article, a rectangular coil in the form of a flexible printed circuit board (F-PCB) with FR4 substrate is designed and fabricated. Owing to its flexibility, the coil can be curved which facilities its use in nuclear magnetic resonance (NMR) spectroscopy. Two samples of this F-PCB coil are faced each other in place, aiming to achieve a range with a uniform magnetic field in the middle of the coils. The performance of the proposed structure is compared with a planar PCB structure. Although the developed coil is intended for NMR spectroscopy, it can also be used in other applications such as wireless power transfer. As a special application, the proposed coil can be adopted in a portable NMR spectroscopy device for analysis and identification of metal minerals. Advantaged from reduced weight and occupied volume, precise design, flexibility and increased efficiency, the presented F-PCB coil can be considered as a promising alternative to the conventional coil. The finite element method (FEM) simulations are performed using COMSOL Multiphysics software and the results have been analyzed in the frequency domain. The results show that the proposed coil has 92% uniformity of the magnetic field in wide frequency range of 3 –6 MHz that is used in NMR. The experimental results obtained from the fabrication device under test are compared with simulation results. The measured magnetic field in the sample area is 102 µT.
Source: Sensing and Imaging - Category: Biomedical Engineering Source Type: research