Design of compact loop-wire medium at radio frequencies for magnetic resonance imaging X. Radu, S. Massaoudi, D.Dragosh, I.Huynen and C. Craeye Université catholique de Louvain, Belgium The first European Conference on Antennas and Propagation (EuCAP), 6-10 November, Nice, France Introduction (1/2) Goal: Design a metamaterial lens suited for magnetic resonance imaging (MRI), to increase its resolution For MRI : required properties of the lens • Adapted to the air • Compact: limited space in the tube Metamaterial = combination of two structures Challenge :frequency is quite low for MRI Spiral resonator [1] low negative permeability at low frequency Solution to satisfy these properties • For the negative permeability structure Use loop wire medium instead [2] Introduction (2/2) • For the negative permittivity structure Loop wire medium good solution to design compact metamaterial with low negative index at MRI frequency [2] D.R. Smith and al. ‘Loop-wire medium for investigating plasmons at microwave frequencies,’ applied physics letters, volume 75, number 10 , 1999 Array of rods : at very low frequency, for a given spacing permittivity tends to be too negative Example : at 123MHz, [1] J.Baena, and al. ‘Artificial magnetic metamaterial design by using resonators ,’ physical review, B169, 2004 1. Simulation method (MoM) and periodic Green’s function 2. Comparison numerical simulation vs. analytical simulation 3. Loop-wire medium principle 4. Parametric studies 5. Metamaterial using loop wire medium 6. Conclusion 7. Further prospects: MBF Outline