Toward an Integrated Wireless Sensor Node for Motion Correction in MRI

MRI is highly sensitive to magnetic field imperfections and patient motion, which can lead to severe image artifacts and reduced diagnostic quality. 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 CMOS IC for wireless NMR field probes. Emphasis is placed on developing an analog front-end and power management circuits that support the excitation and detection of FID signals. Additionally, a clock recovery circuit based on a crystal oscillator and a 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 alignment with a broadcast 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.