Session I: Status Reports on Ongoing and Future Missions Chairs: M.Shimada (JAXA) and P. Snoeij (ESA) Canadian Radarsat Mission status-s. Cote Operating far beyond design lifetime (RSAT-1: 16 years, ASAR: almost 10 years) Mission lives have been extended with measures not planned in original design Radarsat-1 performance within 1dB over 80% of the swath Maneuvers due to space debris collision avoidance increasing ARC is used for the geometric calibration TSX and TDMX mission status M. Zink TsX 4.5 year in orbit, TdX well within requirements Flexible systems allow implementing new modes 250m tube maintenance, and 10cm accuracy of geolocation PPP satellite Two products on DEM are on the shop, 12x12m<10m and level4 < 5m 1 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 1
Session I: Status Reports on Ongoing and Future Missions ALOS-2/PALSAR-2 mission status M. Shimada PALSAR follow-on satellite carrying L-band SAR and to be Launched in August 2013 Orbit cycle 14 days and 500m orbit tube to increase the interferometric coherence RA will be issued July 2012 Calibration sites will selected globally Sentinel-1 constellation P. Snoeij Commissioning Phase outline presented TOPS mode new element 3 months commissioning challenges 7 years mission life in dawn-dusk orbits using the same frequency with Radarsat. 2 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 2
Session I: Status Reports on Ongoing and Future Missions SAOCOM constellation M. Thibeault Soil moisture mapping for the Panpa is one of the main system drivers, Polarimetry data will be used. Uses TOPSAR mode Validation plan in progress Joint project with Cosmo-skymed: SIASIGE Tandem-L mission proposal M. Zink 15 meter reflector with digital beam steering and analogue beam forming, scan on receive Helix orbit and 2 global coverage a week. Soil moisture at 50 m product size 5-10 vol% 3 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 3
Session II: SAR Sensor Calibration and Validation Activities Chairs : S.Côté (CSA) and M.Thibeault (CONAE) TanDEM-X SAR System Verification (Mathias Weigt, DLR) The performance of the TDX satellite is outstanding, with aspects unique to close formation flying validated through separate monostatic and bistatic commissioning, including inter-satellite interference, mutual illumination avoidance, synchronization. In-Orbit Calibration of Both TDX Satellites (Dirk Shrank, DLR) A calibration strategy based on antenna model & on-board calibration allowed to efficiently calibrate and validate the very accurate radiometric and geometric performance of TDX, matching TSX on all aspects. TDX DEM Performance and Calibration (Manfred Zink, DLR) For certain areas, relative height requirement (<2m) is achieved with a single acquisition; coherence is improved for forest areas through formation adaptation. Interferometric and baseline calibration is accurate to 1 mm, with absolute height errors <10m before DEM calibration; DEMs show remarkable quality. 4 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 4
Session II: SAR Sensor Calibration and Validation Activities Interferometric TanDEM-X Data Processing First Operational Experiences (Birgit Schättler, DLR) Operational processing of global DEM data started end of Aug. 2011, and processing is reliable and accurate: excellent performance of bistatic synchronisation, and radargrammetry is used to derive absolute height information in addition to interferometric phase information, without the need of external reference data. SAOCOM Calibration Strategy (Marc Thibault & Julian Giardini, CONAE) On-board and external calibration concepts are integrated with an antenna model for the calibration strategy. Internal calibration performance, with a focus on drifts estimation accuracy, was presented. Corner reflectors (X & L bands) are being deployed in Argentina, and areas of Amazon and possibly Congo will be exploited as distributed targets. 5 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 5
Session II: SAR Sensor Calibration and Validation Activities Canadian Governement Calibration Activities: Assessment of Distributed Target Sites Within the RADARSAT Program (Stephane Cote, CSA) Radiometric cal-val of current and future space-based SARs would benefit from further characterization of natural sites. R2 data show that areas of Cameroon share many Amazon properties while the Dome-C region in Antarctica displays very good stability and smoothness in co-pol. Assessment and Calibration of Polarimetric RADARSAT-2 Using Transponder Measurements (Ridha Touzi, CCRS) Based on a new approach making use of a polarimetric transponder, R2 antenna cross-talk is low (-32 db) even before pol. calibration, and product-supplied pol. calibration is good for general applications. The transponder technique could be a calibration option where very low cross pol. returns are needed. 6 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 6
Session II: SAR Sensor Calibration and Validation Activities AirMOSS P-Band SAR Calibration (Alexandra Chau, JPL) For this radar, the calibration is based on temperature sensing, internal calibration paths, and corner reflectors for radiometric and geometric validation. In addition to the Rosamond CR array, a series of larger, 4.8m CRs were designed with a modular approach using triangular panels as building elements. 7 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 7
Session II: SAR Sensor Calibration and Validation Activities Statements / Recommendations TerraSAR-X and TanDEM-X demonstrate outstanding performance levels. It would be very interesting to have samples available for scientific use. With the increasing number of SAR beams available per mission, the use of an antenna model answers to the need for efficient cal-val (together with internal calibration, natural and artificial targets). To increase robustness & flexibility of space-based SAR cal-val, characterization of natural targets other than the Amazon should be pursued with current missions, in multiple bands (L, C, X). R2 has very good antenna isolation. When polarimetrically configurable, transponders could prove to be useful tools in estimating low cross-talks. P-Band airborne SAR calibration for soil-moisture applications represents distinctive challenges: need of large artificial targets, and high accuracy due to saturation of backscatter levels with soil moisture. 8 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 8
Distributed Target Sites (RADARSAT Program) Distributed Target Sites Satellite Modes (tested by CSA) Lat-Lon Polygon Used by Comments Amazon Prime area RADARSAT-1 RADARSAT-2 9 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 9 All Greater Amazon 1-E RADARSAT-2 All Greater Amazon 1-W RADARSAT-2 All Greater Amazon 2-E RADARSAT-2 All Greater Amazon 2-W RADARSAT-2 All Canadian Boreal Forest RADARSAT-1 Wide Standard Extended High Cameroon RADARSAT-2 All (under validation) Dome-C RADARSAT-2 All (under investigation) Co-pol 6.617092S 68.471545W 7.893549S 68.446272W 7.884001S 66.886225W 7.407580S 66.887274W 7.397836S 66.562979W 6.103395S 66.557360W 6.096117S 67.922924W 6.608517S 67.923008W 4.976390S 71.190000W 4.976390S 74.000000W 7.246940S 74.000000W 7.246940S 71.190000W 4.362500S 70.208890W 6.377780S 70.204440W 6.384440S 68.278330W 4.362500S 68.278330W 1.109720S 62.805000W 1.109720S 64.916670W 2.551110S 64.916670W 2.551110S 63.966670W 3.205280S 63.966670W 3.205280S 62.009170W 1.550000S 62.009170W 1.550000S 62.805000W 4.362500S 70.208890W 6.377780S 70.204440W 6.384440S 68.278330W 4.362500S 68.278330W 51.266667N 84.607778W 49.655556N 85.248056W 49.291667N 82.760556W 50.891944N 82.022778W 51.266944N 84.583611W 4.14129N 13.48798E 4.13572N 13.48798E 4.15119N 12.19741E 2.59908N 12.26637E 2.61134N 13.53829E 73.75806S 123.35000E 73.83250S 121.70222E 74.04917S 120.21111E 74.38667S 119.03028E 74.81083S 118.30222E 75.27500S 118.14667E 75.72472S 118.63444E 76.10167S 119.75889E 76.35333S 121.40556E 76.44167S 123.35000E 76.35333S 125.29444E 76.10167S 126.94111E 75.72472S 128.06556E 75.27500S 128.55333E 74.81083S 128.39778E 74.38667S 127.66972E 74.04917S 126.48889E 73.83250S 124.99778E MDA MDA CSA MDA CSA MDA CSA MDA CSA CSA CSA CSA Area was used by CSA as the prime area for RADARSAT-1 for about 10 years. Well-characterized and accepted as an international area in 2004 by the Committee on Earth Observation Satellites, SAR Cal/Val Working Group. Is also the prime area for RADARSAT-2 for absolute radiometric calibration (MDA). JAXA (Japan), ESA and DLR have areas that contains this area, or that have been contained by this area. Area validated by CSA with RADARSAT-1 in 2006 in support of MDA, to enlarge the valid Amazonian calibration sites in anticipation of the large number of RADARSAT-2 modes to be monitored. Validated since 2003, used as the prime RADARSAT-1 site since 2008 after the termination of the RADARSAT-1 On-Board Recorder, use which allowed cost-efficient data acquisition over the Amazon. Amazon is out of reach of any active and certified receiving facility. This Boreal Forest site near Hearst, Ontario, is within reach of both Prince Albert and Gatineau facilities. Area under validation Area under investigation
Session III: Advanced Calibration Methods Chairs : M. Zink (DLR) and F.Meyer (UAF) Frequency/bandwidth allocations for remote sensing have to be defended and possibly enlarged (L-Band to 120MHz, X-Band to 1200MHz) interference from ground radars expected to increase New statistical approach for correcting ionospheric distortions is under investigation more reliable phase estimation from interferometric stacks expected Super sites for which remote sensing data as well as ground truth can be shared shall be supported - the Laurentides Reserve in Quebec is a good example for such a site Free access to software packages like GMTSAR INSAR software is highly recommended. These packages shall be validated e.g. via comparison with similar tools. 10 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 10
Session IV: Emerging SAR Techniques Chairs : D.Atwood (UAF) and B.Schättler (DLR) Shimada: Model-based Polarimetric Calibration Alternative method to SAR calibration using quad-pol (without assumption of reciprocity). Results comparable, but different from alternative means. Validity demonstrated by resultant polarimetric signature. Schattler: Advances in Pixel Location Accuracy Outline efforts to achieve (upgraded) 1m pixel location specs. Effects of ionosphere, troposphere, solid earth tides, and continental drift must be modeled and removed. Result is geolocation accuracy that permits glacier velocity studies, co-seismic motion measurements, and reference for optical imagery. Meyer: Modeling Atmospheric Signals Turbulent atmosphere poses challenges for interferometry. Can it be 1)accurately modeled with WRF or 2) just stochastically characterized? WRF yields poor phase screen, but offers excellent linearity in variance. Variance magnitudes are underestimated by 3x. 11 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 11
Session IV: Emerging SAR Techniques Hawkins: Residual Motion Compensation for Repeat Pass Despite 5m flight tubes for UAVSAR, residual motion poses problems for repeat track interferometry. Use image correlation to determine baseline slopes. Use correlation to remove bad data Pi: Sounding from Low Earth Orbit Proposed OASIS will use 45MHz signal to sound subsurface beneath sand and glacial ice. Problem is impact of atmosphere on VHF signal. Rigorous modeling points to data collection during 4AM passes. 12 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 12
Session V: Emerging SAR Applications Chairs : W.Boerner (UIC) and M.Thankappan (GA) Making UAVSAR More Accessible from PolSAR Classification D. Atwood Polarimetric L band SAR developed by JPL flown on Gulfstream III aircraft but built for UAV; 20 km swath width Good data holdings from the collections ASF is the distribution centre Value-added products Need for radiometric normalisations for accurate classification Results of UAVSAR Airborne SAR Repeat-Pass Interferometry R.Muellerschoen Demonstrated multi-aperture interferometry can produce azimuth displacements comparable to amplitude correlation displacements Potential advantages of MAI range displacements uncorrelated from azimuth estimates 13 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 13
Session V: Emerging SAR Applications The Alaska Satellite Facility s InSAR Initiative G.Bryson User interface that has provision of InSAR compatible settings for data discovery 2 million granules in the archive 4 InSAR product packages Ground Based Radars Applied to Glacier Observation M.Fahnestock Demonstration of glacier applications Importance of satellite based long-term observation of glaciers UAV Based Remote Sensing Efforts at UAF G.Walker UAV based applications for hazardous, inaccessible environments using lightweight payloads (still / video cameras and X-band SAR) 14 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 14
Session V: Emerging SAR Applications Sub-Mesoscale Imaging of the Ionosphere with SMAP X.Pi How to turn SMAP into a Faraday Polarimeter Ionospheric precursor of earthquakes? Heike 2011 15 Thursday SAR Cal-Val 04-Jun-2009 Workshop 2011 15