Sentinel-1 EW mode RTC Scaling

[ibrown222]

Hi,
I've downloaded Sentinel-1 Extra Wide swath mode RTC products as GRD-M processed data. They are 16-bit unsign integers (as I suppose you know). The scaling I cannot work out: data values range from ca. 76 to >2000. As a gamma nought product I assume i can convert to another scaling. Please tell me if, and how, I can convert to power in dB or linear scaling. I'd be very grateful. Thanks for a great service.

[ASF-EDL - bhauer]

Hello,
Where are you downloading these S-1 GRD-M RTC products from? RTC processing of medium-resolution GRD data is not an option with the HyP3 On Demand service.

[ibrown222]

Hi, thanks for your response. I'm getting them from the Vertex Geographic search to fill in gaps in IW-mode SLC coverage. I assumed that as they are GRD processed they were delivered as sigma or gamma nought but perhaps I misunderstood.

[ASF - bhauer]

The GRD products are map projected. But they are not geometrically or radiometrically corrected (RTC), so retain the distortions introduced by side-looking radar.

I recommend using the SNAP Microwave Toolbox for applying geometric corrections and different calibrations to EW GRD medium-resolution products.

[ibrown222]

Thanks Bill, much appreciated.