The document summarizes research using fully polarimetric TerraSAR-X data for scientific analysis. Key findings include: 1) TerraSAR-X was able to achieve high quality polarimetric data and stable radiometric calibration over multiple years of operation. 2) Analysis of agricultural, urban, glacial and sea ice sites showed polarimetry can provide information on surface changes and feature separation in different environments. 3) Coherent scatterer detection techniques were able to identify stable radar targets in urban and glacial sites at high spatial resolution.

1. Fully Polarimetric TerraSAR-X Data: Data Quality and Scientific Analysis Irena Hajnsek 1/2 , Kostas Papathanassiou 1 , Thomas Busche 1 , Thomas Jagdhuber 1 , JunSu Kim 1 , Maria Sanjuan Ferrer 1 , Stefan Sauer 1 , Michelangelo Villano 1 1 Microwaves and Radar Institute & ²Institute of Environmental Engineering, ETH Zurich

2. TerraSAR-X: DRA Mode Campaign Announcement of Opportunity: DRA Mode data available: simplified proposal procedure and free of charge ! Defined test site (over selected areas): 356 Data takes Campaign duration: 3 cycles (33 days - April 11 and May 13, 2010) StripMap mode (15 km swath width, 3 m resolution) http://sss.terrasar-x.dlr.de

3. Selected Test Sites At least 42 test sites with 3 repeat cycles (repeat pass Pol-InSAR) Europe

4. North America

5. Arctic Sea

6. Principle Transmit: the full antenna is used Receive: the antenna is ‚electrically‘ divided into two sections in azimuth direction (two independent receive channels are available) TS-X Experimental Modes Along-Track Interferometry (ATI) Quad Polarisation Transmit Receive Dual Receive Antenna Mode (DRA Mode) RX2 RX1 V H HH V H HH CH1 H H H H RX1 VV H V VV H V CH2 V V V V RX2 V H V H TX Polarisation Mode

7. TerraSAR-X Calibration Results 0.39 dB 0.18 dB 0.15 dB (2 years) < ±0.2 dB no measurements no measurements < ±0.2 dB 0.31 m 0.54 m < 0.001° < 0.004° 0.38 dB / 0.49 dB 5.1° / 2.4° 80 sec DT length < 0.05 dB < 0.9° Re-Calibration (2009) Radiometric Calibration Antenna Model Verification Geometric Calibration Antenna Pointing Knowledge T/R Module Characterisation Internal Calibration 0.6 dB 1.1 dB Absolute Radiometric Accuracy 0.31 dB 0.68 dB Relative Radiometric Accuracy 0.2 dB (after launch) 0.87 dB Radiometric Stability < ±0.2 dB < ±0.1 dB ±0.2 dB ±0.1 dB Beam-to-Beam Offset two-way over rain forest one-way over ground receiver < ±0.1 dB ±0.1 dB Azimuth Pattern Accuracy (one-way) < ±0.2 dB ±0.2 dB Elevation Pattern Accuracy (two-way) 0.30 m 0.53 m 2 m 2 m Pixel Localisation Accuracy Range Azimuth < 0.002° 0.002° Azimuth < 0.006° 0.015° Elevation 0.38 dB / 0.56 dB 5.3° / 2.6° - - Individual TRM Setting (1- σ ) : Amplitude (Tx / Rx) Phase (Tx / Rx) < 0.05 dB < 0.7° 0.05 dB 0.7° Temp Freeze Amplitude Phase Status Commissioning Phase (2007) Goal

8. System and Propagation Distortion Model X-Talk: On Receive: and On Transmit: and Tx Channel Imbalance: Rx Channel Imbalance: Rx Distortion Tx Distortion Scatterer Propagation Propagation Add. Noise

9. 2 nd Order Descriptors: Polarimetric Coherences: Valid for Reflexion Symmetric Scatterers

10. Rx/Tx Distortion Matrices

11. Agricultural Test Site: Wallerfing (Germany) Acquisition dates: 14 April 2010 25 April 2010 06 May 2010

12. 14/04/2010 25/04/2010 06/05/2010 Subset of Wallerfing for 3 Different Dates @ Pauli RGB

13. Cross-Pol Ratios HV/VH 14/04/2010 25/04/2010 06/05/2010

14. 14/04/2010 25/04/2010 06/05/2010 Polarimetric Coherence Histograms (Amplitude) hhvv hvvh hhhv vvvh hhvv hvvh hhhv vvvh hhvv hvvh hhhv vvvh Polarimetric Coherences (Amplitude)

15. 14/04/2010 25/04/2010 06/05/2010 Polarimetric Coherence Histograms (Phase) hhvv hvvh hhhv vvvh hhvv hvvh hhhv vvvh hhvv hvvh hhhv vvvh Polarimetric Coherences (Phase)

16. SNR Estimation: Reciprocity: SNR Estimates from HVVH Coherence

17. SNR Estimates from hvvh Coherence 14/04/2010 25/04/2010 06/05/2010

18. Polarimetric SAR for Different Applications: Examples Wallerfing (Agriculture) Change of polarimetric feature depending on crop phenology Repeat pass Pol-InSAR coherence analysis San Francisco (Urban Area) Urban area application for feature separation and interpretation Argentiere & Aletsch (Glaciers) Coherent Scatterer detection Ward Hunt Ice Shelf (Sea Ice) Change of sea ice feature

19. 14/04/2010 25/04/2010 06/05/2010 Polarimetric Ratios HH/VV @ X-band 49.1% 39.0% 51.4% VV>HH 17.8% 37.9% 44.2% VV>HH Sugar Beet Winter Wheat Dates HH>VV HH>VV 48,6% 55.8% 14/04/2010 61.0% 62.1% 25/04/2010 50.9% 82.2% 06/05/2010

20. Entropy/Alpha Angle @ X-band 14/04/2010 - Entropy 25/04/2010 - Entropy 06/05/2010 - Entropy Entropy/Alpha Entropy/Alpha Entropy/Alpha

21. Interferometric Coherences @ Different Polarisations April 25 th - May, 6 th April 14 th - May, 6 th April 14 th - April, 25 th |  HV12 | |S HV1 | ||S HV1 |-|S HV2 || |  VV12 | |S VV1 | ||S VV1 |-|S VV2 || |  HH12 | |S HH1 | ||S HH1 |-|S HH2 ||

22. San Francisco (11/04/2010)

23. range |HH+VV| |HH-VV| |HV| Double-bounce Single-bounce Triple-bounce Alpha_1 0 Double-bounce Single- bounce Triple-bounce Polarimetric TSX Image of the Golden Gate Bridge

24. Alpha_1 0 Double-bounce Single-bounce Triple-bounce Double- bounce Polarimetric TSX Image of the Golden Gate Bridge

25. Coherent Scatterers (CSs) Detection Method: Phase Variance Approach Based on the deterministic phase pattern across the spectrum characteristic of the CSs. It allows a widely preservation of the spatial resolution in the CSs detection . Common detection: Only the CSs that have a phase derivative variance σ ² lower than a given threshold in both directions (range and azimuth) are considered as detected CSs. 10 sublooks of 60 MHz each out of the 150 MHz range bandwidth are formed and the variance σ ² of the phase derivative for every pixel is estimated. 10 sublooks of 552 Hz each out of the 1380 Hz azimuth bandwidth and the variance of the phase derivative for every pixel is estimated. Fixing a threshold ( σ ² ), pixels with a phase derivative variance lower than the threshold in range and azimuth at the same time will be considered as a detected CSs.

26. CSs Detection on the Argentiere Glacier (France) CR

27. CR CR σ ²=0.0025 rad ² σ ²=0.0064 rad ² σ ²=0.0144 rad ² CR IM (13-04-10) Argentiere Glacier (France): Coherent Scatterer Detection

28. IM1 (13-04-10) IM2 (24-04-10) IM3 (05-05-10) σ ²=0.0081 rad ² Aletsch Glacier (Switzerland): Coherent Scatterer Detection

29. Pauli RGB Composites Ice Shelf Land Fast Ice Pack Ice Ward Hunt Ice Shelf RadarSAT-2 Blue line 2001 Red line 2008 Eastern Ward Hunt ice shelf showing long (up to 15 km) meltwater lakes that form every summer on the ice surface. -ää (http://madzu.com/ellesmere/Ward_Hunt.html) 2010/04/13 2010/04/24 2010/05/05

30. and and = H and V Symmetry Rx and Tx Symmetry Reciprocity

31. SNR Estimates from 2D eigenvalue matrix 14/04/2010 25/04/2010 06/05/2010

32. CSs Detection on the San Francisco Scene (USA) σ ²=0.0025 rad ² σ ²=0.0064 rad ² σ ²=0.0144 rad ²