MRI B1 Optimization using Coupled Coil Modal Analysis

Motivation: In low field MRI, a strong, uniform B1 field helps improve deep tissue imaging. This is particularly challenging for one-sided MRI systems. Goal(s): Strengthen the B1 field in deeper regions of interest to decrease sequence time and improve SNR. Approach: A floating TX coil was developed, which when coupled to the system TX coil, enables a B1 enhanced mode within the desired bandwidth. Using analytical methods and iterative testing, this interaction is optimized. Results: Using analytical methods we determined the tuning parameters for each coil and achieved the desired B1 enhanced mode and optimized B1 field performance in both strength and uniformity. Impact: This adaptable analytical approach, employing a secondary coil to enhance the TX coil's B1 field uniformity and localization, supports improved MRI imaging quality and enables our one-sided MRI system to image deeper into the body.