Feng Zhao1, Jeffrey A. Fessler2, Jon-Fredrik Nielsen1, Daehyun Yoon2, Douglas C. Noll1
1Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States; 2Electrical Engineering, University of Michigan, Ann Arbor, MI, United States
Bloch-Siegert (BS) B1 mapping is a promising method for multi-coil B1 mapping, but it may produce B1 maps with low SNR in low magnitude regions. Furthermore, estimation of relative B1 phase maps of multi-coil systems needs another set of scans. In this work, we propose a regularized method to jointly estimate the magnitude and (relative) phase of multi-coil B1 maps from BS B1 mapping data without using additional scans for the phase estimation. By utilizing the prior knowledge of B1 maps, the regularization terms for magnitude and phase can help improve quality of the B1 maps in low magnitude regions.