A method for reducing maximum local specific absorption rate ("SAR") in a
magnetic resonance imaging ("MRI") system is disclosed. More
specifically, a plurality of candidate radio frequency ("RF") pulses are
designed and the manner in which they are applied to a subject is
determined such that the maximum local SAR is substantially reduced
relative to applying the candidate RF pulse that produces the lowest
maximum local SAR alone. Put another way, this "time-multiplexing" of a
set of RF pulses that each produce approximately the same excitation
pattern yields a lower maximum local SAR than does transmitting the
individual RF pulse having the lowest local SAR over many repetition
times ("TRs"). A convex optimization method is utilized to determine the
manner in which the RF pulses are multiplexed in time such that a
substantially lower maximum local SAR is achieved.