Fig. 4

The surface current distributions of the F-MDSRR microstructure, S-MDSRR microstructure, and ground plane and the near electric fields of the PMA at the resonance frequency of 5.13, 14.49, 19.05, 20.77, and 25.42 GHz. a Surface current distributions at 5.13 GHz. b Near electric fields distributions at 5.13 GHz. c Surface current distributions at 14.49. d Near electric fields distributions at 14.49 GHz. e Surface current distributions at 19.05 GHz. f Near electric fields distributions at 19.05 GHz. g Surface current distributions at 20.77 GHz. h Near electric fields distributions at 20.77 GHz. i Surface current distributions at 25.42 GHz. j Near electric fields distributions at 25.42 GHz