Challenges and Prospects to Time Series Burst Overlap Interferometry (BOI): Some Insights From a New BOI Algorithm Test Over the Chaman Fault

How to obtain millimeter-scale along-track deformations using phase measurements is still a pending question for interferometric synthetic aperture radar (InSAR) community. Although burst overlap interferometry (BOI) technique makes this question seem tractable, most applications of BOI still focus on extracting centimeter-scale deformations for coseismic cases. To further improve measurement accuracy, here we propose a new time series BOI algorithm toward maximizing the performance of BOI and obtaining as high accuracy of the along-track deformations as possible. This algorithm has three major steps. The first step is to enhance BOI phase signal-to-noise ratio (SNR) using our newly proposed phase estimator. In the second step, we apply a strain model-based method to further suppress the phase noise and rescue more data points. In the third step, a misregistration correction procedure which considers plate motion is applied to mitigate BOI time series bias. We tested our proposed algorithm over the Chaman fault. Although the derived millimeter-scale deformations demonstrate the effectiveness of our method, experimental results show that decorrelation and ionospheric disturbance are still two great challenges of BOI techniques.