An Ultra-Low Output Impedance Power Amplifier for Tx Array in 7-Tesla Magnetic Resonance Imaging

In Ultra high-field MRI scanners (3T and higher),
parallel RF transmission techniques using multiple RF chains with
multiple transmit elements are a promising approach to overcome
the high-field MRI challenges in terms of inhomogeneity in the RF
magnetic field and SAR. However, mutual coupling between the
transmit array elements disturbs the desirable independent control of
the RF waveforms for each element. This contribution demonstrates
a 18 dB improvement of decoupling (isolation) performance due to
the very low output impedance of our 1 kW power amplifier.

Authors:

• Ashraf Abuelhaija
• Klaus Solbach

Keywords:

• EM coupling
• Inter-element isolation
• Magnetic resonance imaging (MRI)
• Parallel Transmit.

References:

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