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quality in high field MRI is limited by B1 inhomogeneity. This work describes a
new approach to improving B1 homogeneity using parallel transmission. Rather
than transmitting a conventional traveling wave, which is diffracted and
reflected by the human body, thereby creating a non-uniform internal field, the
new method seeks a solution to the inverse problem—what external field produces
a traveling plane wave within the body? Simulations suggest dramatic
improvements in B1 homogeneity can be obtained given a sufficient number of
transmitted field modes.