Assessment of Conventional Unwrapping Methods Presented to Unwrap Interferometric Phases

InSAR technique can be used for extracting topography and estimating ground surface displacements. Phase unwrapping is one of the most important parts of displacement estimation from an interferogram affecting the results. Because of the nature of the phase unwrapping problem, finding the number of missed integer cycles is critical and demanding. If the conventional method is considered for interferometry, phases will spread regularly. In recent years, several algorithms have been presented to unwrap data in regular spaces. Since a comprehensive study has not been done for unwrapping methods evaluation yet, the main goal of this paper is to introduce and investigate the performance of the most important unwrapping algorithms. Moreover, unwrapping methods presented in regular space are thus investigated. Moreover, their advantages and disadvantages are fully discussed. Because regular-space methods are usually considered to unwrap phases, a number of efficient conventional unwrapping approaches have been implemented on an interferogram processed from ENVISAT ASAR satellite images acquired over the Tehran basin northeast.