Embodiments of the subject invention can utilize a single coil structure
for dual-mode operation. In a specific embodiment, a single coil
structure can be used as a volume coil in the transmitting phase and as a
phase array in the receiving phase. In an embodiment, a transmit coil
array in accordance with the subject invention can be utilized for one or
more of the following: 1) parallel RF excitation on an MRI scanner
equipped with a multiple-channel transmitter; 2) serial RF excitation
with the use of a switch system with a single channel transmitter; and 3)
generation of a homogeneous B.sub.1 field for regular MRI with the use of
a power splitter on a standard scanner. In a specific embodiment, the use
of a concentric double loop coil with different tunings of inner and
outer loops can be implemented. In an embodiment, the coil elements can
be decoupled using the CRC mode of a concentric double loop coil. In an
embodiment, a surface coil transmit array can provide better
compatibility with a receive array. In a specific embodiment, an
over-coupled technique can be used to improve the phase control of the
transmitting pulse.