High linearity non-magnetic RF power amplifier for 5T MRI

Motivation: Accurate RF excitation in MRI requires a linear response from the radio-frequency power amplifier (RFPA). However, the conventional RF power amplifier (RFPA) used in MRI is typically located in the equipment room, which introduces complexity and significant signal losses. Additionally, it poses challenges to direct control of RF signals at the RF coil side. Goal(s): Design high power and high linearity RFPA which can operate in a strong magnetic field environment. Approach: The design incorporates non-magnetic high-power circuits and a negative feedback control module. Results: The amplifier exhibits high power and linearity characteristics during the bench testing. Impact: The proposed design method for non-magnetic RFPA can enhance the efficiency and linearity of RF excitation in MRI, multiple non-magnetic RFPAs will be fabricated to facilitate parallel transmission in 5T MRI.