Unknown phase in ALOS-1 interferogram

[Sayyed Mohammad Javad Mirzadeh]

Hi,

I downloaded the ALOS-1 Level 1.0 data from ASF Vertex and processed it using ISCE (v2.6.1) and MintPy (v1.5.1). However, I noticed a strange signal appearing consistently across all interferograms, as shown in the attached example. Interestingly, I 

Could you please share your thoughts or suggestions on how to address this issue? I’m not sure about the possible causes and would appreciate your guidance.

Sincerely,

Sayyed

[Tara Shreve]

Hi Sayyed,

It's possible that the DEM used in processing does not cover the entire SAR scene. The fringes could be due to topography, and the smooth phase on the right side of the scene is where the topographic fringes were correctly removed. 

Best,

Tara

[Sayyed Mohammad Javad Mirzadeh]

Thank you, Tara. Your guess is right, and I fixed it by checking the DEM file.