Abstract Normal difference interferograms record phases with an un-integer cycle. An unwrapping procedure is needed to recover the true ground deformation. Due to external factors, such as earthquake occurrence and fault effect, the interferograms are vulnerable to unwrapping error. The positioning of the errors is vital to further computation. This paper, based on Sentinel-1A data, proposes a checking unwrapping error method with multiple closed loops of interferograms. It takes Mexico city as the study area. Its good consistency represents better results.
