Snaphu unwrapping orbit radius less than earth radius

hello. I’m an amateur working with snaphu unwrapping
i’m getting an error with unwrapping where it says that the platform orbit radius must be greater than the earth orbit radius. I’m not sure how to respond or adress this issue.

Here is the snaphu configuration

CONFIG FOR SNAPHU

----------------------------------------------------------------

Created by SNAP software on: 13:38:54 17/10/2019

Command to call snaphu:

snaphu -f snaphu.conf Phase_ifg_VV_01Sep2019_20Aug2019.snaphu.img 3414

#########################

Unwrapping parameters

#########################

STATCOSTMODE DEFO
INITMETHOD MCF
VERBOSE TRUE

###############

Input files

###############

CORRFILE coh_IW1_VV_01Sep2019_20Aug2019.snaphu.img

################

Output files

################

OUTFILE UnwPhase_ifg_VV_01Sep2019_20Aug2019.snaphu.img
#LOGFILE snaphu.log

################

File formats

################

INFILEFORMAT FLOAT_DATA
CORRFILEFORMAT FLOAT_DATA
OUTFILEFORMAT FLOAT_DATA

###############################

SAR and geometry parameters

###############################

TRANSMITMODE REPEATPASS

ORBITRADIUS 1.407649532968525E15
EARTHRADIUS 1.13872371361364592E17

LAMBDA 0.0554658

BASELINE 1.4076495332367362E15
BASELINEANGLE_RAD 4.706

NEARRANGE 798985.8535428

Slant range and azimuth pixel spacings

DR 13.9773727
DA 3.53145338676195E7

Single-look slant range and azimuth resolutions.

RANGERES 2653030.6017161
AZRES 9.27211151423343E7

The number of independent looks: approximately equal to the

real number of looks divided by the product of range and

azimuth resolutions, and multiplied by the product of the

single-look range and azimuth spacings. It is about 0.53

times the number of real looks for ERS data processed

without windowing.

NCORRLOOKS 23.8

################

Tile control

################

NTILEROW 1
NTILECOL 1

ROWOVRLP 0
COLOVRLP 0

NPROC 4

TILECOSTTHRESH 500

End of snaphu configuration file

any help would be much appreciated!

Steps of snaphu Algorithm for phase unwrapping , To run the unwrapping in snaphu follow steps bellow:

  1. In SNAP use the Radar -> Interferometric -> Unwrapping -> Snaphu Export tool to export the wrapped interferogram;
  2. Navigate to the folder containing the exported data using File explorer;
  3. Right click the snaphu.conf file and open it with Mousepad;
  4. Copy the command at line 7 (to avoid errors with the number of lines);
  5. In command line, navigate to the folder where your data are stored and run the coppied command;

Example:
cd /shared/data/sentinel1/snaphu/S1A_IW_SLC__1SSV_20161016T105004_20161016T105031_013514_0159DC_4744_Orb_Stack_ifg_deb_flt_ML/
snaphu -f snaphu.conf Phase_ifg_IW3_VV_16Oct2016_22Oct2016.snaphu.img 5952

If you receive an error go back to the snaphu.conf and place comment before LOGFILE. Line 28 should then be: # LOGFILE snaphu.log

Keep in mind, that you need the multilooked product (input for Snaphu Export ) to import the unwrapped phase back to SNAP. So you could use for example following graph to preprocess your data (input is coregistered stack, the steps can vary based on application):

Import to SNAP
To import the unwrapped phase from SNAPHU processing, go to Radar -> Interferometric -> Unwrapping -> Snaphu Import . In the first Read tab , select the multilooked product, in the second Read tab , navigate to the snaphu folder and import the Unwrapped*.hdr file (not the .img).

Source: https://rus-copernicus.eu/forum/t/snaphu-how-to-run-snaphu-unwrapping-on-rus/120

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