Fig 1. Numerical models of a 1.5 T 16-rung low-pass birdcage coil tuned at 64 MHz, a 3 T 16-rung low-pass birdcage coil tuned at 127 MHz, a 7 T 16-rung hybrid birdcage coil tuned at 297 MHz, and a 10.5 T 8-channel bumped dipole array tuned at 447 MHz all loaded with a homogeneous human head model with no implant.

The geometrical dimensions of the coils were the same as the coils reported in literature [18–21].