Dependence of near field transmit properties at 300 MHz of array element spatial distribution

We present a numerical investigation of the RF fields generated by a parameterized set of loop array configurations using RF circuit and frequency domain 3-D EM co-simulation. When circular polarization mode excitation of the entire human brain is used, single row arrays with the closest possible element spacing, whether of 4, 8 or 12 elements, deliver the largest fraction of the available transmit power to the brain, and provide not only the best transmit performance for the entire volume and specific slices, but also the minimum possible SAR. Increasing the gap between coil elements, and staggering the element rows, both decrease both transmit and safety indices.