The Heartbeat of Magnetic Resonance Imaging: RF Power Amplifiers in MRI Scanners

This article provides an overview of Radio Frequency (RF) power amplifiers (PAs) as an Essential To Function (ETF) sub system within Magnetic Resonance Imaging (MRI) scanners. It discusses the fundamental role of RF PAs in generating the high-power RF pulses necessary for exciting nuclear spins and acquiring MR signals. Key considerations for RF PA design in MRI are explored, including, linearity, bandwidth, pulse fidelity in order to handle various MRI RF pulse sequences. The article will also touch upon MRI history, current challenges and future trends in RF PA technology aimed at improving MRI system performance, particularly concerning higher field strengths, image resolution and parallel transmission(B1 shimming/PTx).