Error of DInSAR interferogram

Microwave Toolbox
1

Hello everyone
DATA: S1A_IW_SLC__1SSV_20150912T012217_20150912T012244_007675_00AA76_08F2
S1A_IW_SLC__1SSV_20150912T012242_20150912T012309_007675_00AA76_523C

     S1A_IW_SLC__1SSV_20151006T012217_20151006T012244_008025_00B3C7_6B96
     S1A_IW_SLC__1SSV_20151006T012242_20151006T012309_008025_00B3C7_BE4D

orbit:precise orbit
SNAP sentinel-toolbox version 2.02
step：

Pasted image942×750 110 KB

I use these data to make an interferogram, to be obvious, there are some huge fringe. But there’s no surface modification. so there shouln’t have fringe. Perhapse these fringe are caused by orbit error, but i used precise orbit.
can anyone give me some advice?

Pasted image1525×908 927 KB

thanks a lot!!

2

Based on the rugged terrain in area where you scene was taken, those fringes are due to topology. To remove the topographic phase, find a function Topographic Phase Removal in SNAP.

3

Hi jegrix
I had removed the Topographic Phase befor filter, that’s why i have some confusion about this phenomenon.

thanks