The Subspace Phase Retrieval (SPR) algorithm can accurately recover an n-dimensional k-sparse complex-valued signal from Ω(k log n) magnitude-only Gaussian samples, attaining the information-theoretic sampling complexity for sparse phase retrieval.
This paper proposes two fundamental improvements to the classical Orthogonal Matching Pursuit (OMP) algorithm to make it computationally more efficient while preserving its excellent performance guarantees. The proposed algorithms, OMP-SR and BSR, achieve significant speedup over OMP by avoiding the expensive computation of pseudo-inverse over an increasing-sized matrix.