Estimates of coil parameters and noise for various receive coil geometries (rodent-size (a)–(b), human head-size (c)–(h)). Estimates include: inductance, z component of B1 at center per unit Amp, body load loss (at 3rd harmonic frequency, 30 kHz) for cylindrical objects of conductivity 0.5 S/m ((a)–(b) cylinder: d = 4.5 cm, l = 4.5 cm, (c)–(h) cylinder: d = 22 cm, l = 22 cm), body load noise corresponding to this body load loss in 100 kHz BW, AC resistance in 4 parallel strands of 26 AWG Litz wire at 30 kHz, AC conducting noise corresponding to this AC resistance in 100 kHz BW, and relative detection sensitivity (B1 per unit Amp at center per AC conducting noise).