GERCHBERG-SAXTON AND YANG-GU ALGORITHMS FOR PHASE RETRIEVAL IN A NONUNITARY TRANSFORM SYSTEM - A COMPARISON

A detailed comparison of the original Gerchberg-Saxton and the Yang-Gu algorithms for the reconstruction of model images from two intensity measurements in a nonunitary transform system is presented. The Yang-G u algorithm is a generalization of the Gerchberg-Saxton algorithm and is effective in solving the general amplitude-phase-retrieval problem in any linear unitary or nonunitary transform system. For a unitary tr ansform system the Yang-Gu algorithm is identical to the Gerchberg-Sax ton algorithm. The reconstruction of images from data corrupted with r andom noise is also investigated. The simulation results show that the Yang-Gu algorithm is relatively insensitive to the presence of noise in data. In all cases studied the Yang-Gu algorithm always resulted in a highly accurate recovered phase.