A convex hull algorithm based fast large-scale two-dimensional phase unwrapping method

Abstract

Two-dimensional phase unwrapping (PU) is a critical processing procedure of synthetic aperture radar (SAR) interferometry (InSAR). With the rapid advance of InSAR, the scale of the interferogram is becoming larger and larger. Under the condition of “big-data” PU, there are two new hurdles encountered: i) the dilemma between execution speed and accuracy, ii) the limitation of computing memory. To effectively solve these two problems, a new fast large-scale PU methodology, which is based on the convex hull algorithm and residue clustering characteristics, is discussed in this paper. The theoretical analysis and experiments indicate that this proposed large-scale PU methodology has some desirable potentials for large-scale PU problem: 1) peak memory consumption is very low which can avoid tiling processing; 2) time complexity is approximatively linear; 3) PU solution is as precise as some representative high accuracy PU methods.