The schematic diagram of the experimental samples. (a) MNZ media, the total thickness is h. (b) MNZ metamaterial unit. The side length of the unit is L, and the radius of each single disc is r. The width of the copper is w, the gap is g. The pin a and b of the capacitor is connected to the terminal 2 and 3 by soldering, respectively, and the other terminal 1 is connected to the terminal 4. (c) A single ferrite slab. The side length of each bulk is L. The thickness of the slab is 2h. (d) Composite metamaterials with a bulk ferrite. For each ferrite bulk, the side length is L, the thickness is h. (e) Composite metamaterials with a patterned ferrite. For patterned ferrite, the outer length is L, the inner length L₁, and the thickness is h. (f) Non-resonant system. The Tx coil is the same as the Rx coil, the outer length is L₂, the inner length is L₃. The distance between them is S.