Daehyun Yoon1, Ray Maleh2, Anna C. Gilbert2, Jeffrey A. Fessler1, Douglas C. Noll3
1Electrical Engineering, University of Michigan, Ann Arbor, MI, USA; 2Mathematics, University of Michigan, Ann Arbor, MI, USA; 3Biomedical engineering, University of Michigan, Ann Arbor, MI, USA
We propose a novel, fast method based on a hybrid version of Simultaneous Orthogonal Matching Pursuit(S-OMP) to select sparse phase-encoding locations in a Echo-Volumar(EV) trajectory for parallel excitation pulse design with slice-selective subpulses. Sparse phase-encoding selection was previously presented as a convex optimization problem in a Second Order Cone Program(SOCP) form, which was too slow to be computed on-line in parallel excitation. We present a much faster greedy algorithm, Parallel-OMP(P-OMP), which will solve the same problem in a few seconds with compatible accuracy to that of SOCP in both the single and multiple coil cases.