  In this contribution we present numerical and experimental results of a
parametric quantitative study of radiative dipole antennas in a phased array
configuration for efficient body magnetic resonance imaging at 7T via parallel
transmission. For magnetic resonance imaging (MRI) at ultrahigh fields (7T and
higher) dipole antennas are commonly used in phased arrays, particularly for
body imaging targets. This study reveals the effects of dipole positioning in
the array (elevation of dipoles above the subject and inter-dipole spacing) on
their mutual coupling, $B_1^{+}$ per $P_{acc}$ and $B_1^{+}$ per maximum local
SAR efficiencies as well as the RF-shimming capability. The numerical and
experimental results are obtained and compared for a homogeneous phantom as
well as for a real human models confirmed by in-vivo experiments.
