Advanced MT-InSAR Landslide Monitoring: Methods and Trends

MT-InSAR (Multi-temporal Interferometric Synthetic Aperture Radar) is a powerful remote sensing technique used to measure earth surface displacements and monitor their trend throughout the years over different times. It employs multiple time series of SAR images and extracts spatial height information over large scales of illuminated areas. It is a proficient technique to acquire all season day and night data with high accuracy and wide spatial coverage. Although conventional InSAR technique have vast successful applications but several limitations like decorrelation of phase, error in phase unwrapping and atmospheric artifacts hinders its use, which, in fact, have resulted in the development of more innovative multi-temporal InSAR (MTInSAR) techniques which has proved an enhancement in accuracy and consistency of extracted deformation time series. This paper provides a review of development of MTInSAR techniques, basic principles behind them, their strengths and limitations and a review of the applications of the advanced algorithms proposed in the literature and deformation measurement trends being followed. The paper accomplishes discussions on the main strengths, limitations, cross-comparison among approaches and the associated research trends.