Interferometry from two satellite images S1A and S1B

Hello everyone,

I’m currently focusing on mapping vegetation growth using the interferometry approach. I’ve observed that the 12-day cycle images from Sentinel-1A are not yielding satisfactory results. I’m considering whether it’s possible to utilize both Sentinel-1A and Sentinel-1B for a 6-day cycle instead. Is it scientifically correct to use images from two different satellites?
Does anyone have experience with this, or could provide some guidance on the feasibility of using these satellites with a shorter interval?

Thank you!

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The satellites are for all practical purposes identical so you can use both interchangeably. Currently S-1B is not operational but you can develop your methods using historical datasets.

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Thanks for your response.

Sounds interesting to use interferometry for vegetation growth unless you just consider the coherence loss.

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This approach works for short timeseries. However, for multi-year analysis, mixing S1A and S1B data results in significantly higher dispersion and larger displacement RMSE error. Use a single satellite for higher quality results whenever possible, and mix only when no alternative is available.
The interactive InSAR cases “La Cumbre Volcano Eruption Interferogram, 2020” and “Iran–Iraq Earthquake Co-Seismic Interferogram, 2017” at https://InSAR.dev use a mix of S1A and S1B satellite scenes with excellent results.

The study we have performed in the past has proved that cross-interferograms (S1A-S1B) are providing correct results. Please check the reference paper

P. Prats-Iraola et al ., “Interferometric investigations with the Sentinel-1 constellation,” 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS) , Fort Worth, TX, USA, 2017, pp. 5537-5540, doi: 10.1109/IGARSS.2017.8128258.
keywords: {Orbits;Doppler effect;Bandwidth;Time series analysis;Azimuth;Strain;Urban areas;Sentinel-1;TOPS Interferometry;coregistration;time series},

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From my experience, SNAP produces blank results if S1A and S1B are combined.

Can you identify a S-1A/B pair where this happens to you? I hope you are running fully updated SNAP10 as that is the currently supported version.

Actually, it was SNAP 8 I believe then I tried it last time. It was during the time when S1B was still with us and it was always blank no matter which pair of images and where it was taken. Eventually, I had to use only the same sat in the InSAR pair.