Toward an Integrated Wireless Sensor Node for Motion Correction in MRI

Magnetic resonance imaging (MRI) is highly sensitive to magnetic field imperfections and patient motion, which can lead to severe image artifacts and reduced diagnostic quality. Nuclear magnetic resonance (NMR) field probes provide a means to monitor field dynamics in real-time, enabling motion correction and field stabilization. For clinical deployment and to ensure safety, such probes should operate wirelessly within the MRI bore, maintain strict phase synchronization, and consume minimal power, all while remaining fully compatible with the electromagnetic environment. This thesis investigates the design and implementation of complementary metal-oxide semiconductor (CMOS) integrated circuits (ICs) for wireless NMR field probes. Emphasis is dplaced on developing an analog front-end and power management circuits that support the excitation and detection of free induction decay (FID) signals. Additionally, a clock recovery circuit based on a crystal oscillator and a digital phase-locked loop (DPLL) provides accurate synchronization and robust transmission of triggering events under the challenging conditions of high-field MRI. Silicon measurements confirm low-noise performance, precise timing lignment with a broadcast radio frequency (RF) signal, and successful operation inside MRI scanners. The presented architectures demonstrate that autonomous, wireless, and phase-synchronized NMR field probes can be accompanied by low-power CMOS technology. Beyond enabling real-time motion correction in MRI, these advances open the door to more precise and reliable imaging methods, with potential impact on both clinical diagnostics and neuroscience research, while driving progress in miniaturized sensing technologies.