Abstract
In this paper, we present the design of probe excitations for 7- and 10.5-T traveling-wave wide-bore magnetic resonance imaging systems. The probes are 297- and 447-MHz coaxially fed microstrip patches, designed to give a circularly polarized magnetic field when placed in the metallic bore waveguide. Images of a water phantom using the patch probes are obtained and compared with full-wave electromagnetic simulations. Additionally, periodic axial metal strip cylinders are inserted into the bore, resulting in improved field uniformity in a phantom with a simultaneous increase in SNR. The numerical analysis for nonquasi-static fields can be computationally intensive, and the numerical error for finite-element simulations is quantified using modified boundary conditions of the system. When the waveguide effects are taken into account, the mode content in the images compares well to full-wave simulations.
| Original language | English (US) |
|---|---|
| Article number | 7855781 |
| Pages (from-to) | 2547-2557 |
| Number of pages | 11 |
| Journal | IEEE Transactions on Microwave Theory and Techniques |
| Volume | 65 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 2017 |
Bibliographical note
Publisher Copyright:© 1963-2012 IEEE.
Keywords
- FEM
- magnetic resonance imaging (MRI)
- patch antenna
- waveguide