Asymmetric Tapered Solenoid Designs for Halbach-Based Portable Magnetic Resonance Imaging

Halbach array is a popular permanent magnet used in head dedicated portable MRI. It supplies transversal main magnetic field ( $B_{0}$ ), and it works well with solenoid RF coils when homogeneous. The low. To compensate this, desired to have high coil sensitivity of the that such system. Hence this paper, an asymmetrical tapered was proposed optimization carried out for both profile pitches between turns homogeneity. Multi-objective genetic algorithm used. B notation="LaTeX">$_{1}$ -field calculated using Biot-Savart's law process. targeted view (FoV) 190 mm diameter spherical volume (DSV) imaging. optimized were simulated frequency domain solver CST Microwave studio, physically constructed, compared reference comparable dimensions. optimal design shows increase notation="LaTeX">$\sim$ 35% (calculation), 33% (simulation) minimal trade-off homogeneity 10% (calculation simulation) within DSV. For validation, constructed measured FoV on notation="LaTeX">$xy-$ plane at notation="LaTeX">$z=0$ . results are good agreement results.