Hello,
We are using statistical Hub Api to get the SAR backscatter values on a road segment. While doing that we are using a date range of 1 March 2022 - 31 march 2022. VV values are well received for the time range mentioned, but majority of the VH values are zero on the same road segment. Also at same dates where VV is available, VH is not available. Kindly suggest if this is normal or there is some issue in our approach
Hi Jags,
Please can you provide the full request so that we can look into it. We need the AOI and timerange to be able to debug what is going wrong. Working and non-working examples would be greatly appreciated 
Hi William,
Thanks for the quick response.
Here the screenshot for full request and Area of interest as a shape file.
I am not able to upload the shape file, can you suggest an alternative to share the AOI file
If you can share the geojson string of the area of interest, this is sufficient.
In addition, you are aware that the revisit time of Sentinel-1 was at best 5 days (pre Sentinel-1B failure in 2022)? Since then revisit times are not as good, and parts of the world are not covered at all. You can read more into this in the documentation here.
Sure William,
I am still not able to upload the geojson string here. I have tried using .zip as well. is there any email where I can send that?
Hi,
You can either open the file in a text editor and copy and paste the contents or send the file to info@sentinel-hub.com.
Hi William,
Please have a look at the geojson content here. Looking forward to your response. Understanding these zero values are very crucial now.
{
"type": "FeatureCollection",
"name": "ODR_117_patch_1km_geojson",
"crs": {
"type": "name",
"properties": {
"name": "urn:ogc:def:crs:EPSG::32643"
}
},
"features": [
{
"type": "Feature",
"properties": {
"fid_1": 1.0,
"Id": 29824.0,
"Segment Id": "13560022995077",
"NewSegId": "00004e31-3600-0400-0000-000002b18269",
"Length": 467.86212991836157,
"FRC": 4.0,
"SpeedLimit": 55.0,
"StreetName": null,
"Road_name": "ODR 117\r",
"From": 7.0,
"To": 7.25,
"From_lat": 19.443221,
"From_long": 73.14024397,
"Carriagewa": 3.7,
"PCI": 4
},
"geometry": {
"type": "MultiLineString",
"coordinates": [
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],
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],
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304717.263421228155494,
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],
[
304721.869306270731613,
2150722.305155755486339
],
[
304727.687266324472148,
2150745.819410972762853
],
[
304733.262811375956517,
2150772.727476221974939
],
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304741.020091447629966,
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]
]
}
},
{
"type": "Feature",
"properties": {
"fid_1": 2.0,
"Id": 29824.0,
"Segment Id": "13560022995077",
"NewSegId": "00004e31-3600-0400-0000-000002b18269",
"Length": 467.86212991813562,
"FRC": 4.0,
"SpeedLimit": 55.0,
"StreetName": null,
"Road_name": "ODR 117\r\n",
"From": 6.5,
"To": 7.0,
"From_lat": 19.44734597,
"From_long": 73.141418,
"Carriagewa": 3.7,
"PCI": 5
},
"geometry": {
"type": "MultiLineString",
"coordinates": [
[
[
304809.744744582509156,
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],
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],
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],
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2151489.669845345430076
],
[
304938.467110772035085,
2151515.729458086192608
],
[
304949.193974621186499,
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],
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304959.860234719817527,
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],
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]
]
}
}
]
}
Hi,
For the polygons that you have supplied, there are indeed only two acquisitions in the time period that you requested. I have checked this in Catalog API. The only issue I can see where you might also be missing data is:
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