SAR Interferometry Capabilities of Canada's planned SAR Satellite Constellation

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1 SAR Interferometry Capabilities of Canada's planned SAR Satellite Constellation Dirk Geudtner, Guy Séguin,, Ralph Girard Canadian Space Agency

2 RADARSAT Follow-on Program CSA is in the middle of a Phase A study on a SAR constellation

3 SAR Constellation Objectives Ensure C-band data continuity beyond RADARSAT-2 Meet requirements for key applications: maritime surveillance sea-ice monitoring land surface monitoring & environment disaster management Increase the availability of SAR data and reduce its costs to support operational applications and services Improve system reliability and reduce risk Costs (for 3 satellites) < costs for RADARSAT-1 (about $ CAD 600 Mill.)

4 Change of Paradigm 1 Satellite Imaging Equal User Requirements Pre-tasked 24-day Repeat Orbit 3-6 Satellites Monitoring/ Surveillance Priority User Requirements Near Real-Time Tasking 12-day Repeat Orbit

5 Key Applications Maritime Surveillance: Ship Detection Provide information on location and identification of ships in national waters or from approaching areas for security and fishing control

6 Ship Surveillance: Coverage Requirements Coverage of middle zone every 12 hours at 50 m resolution (25m desired)

7 Key Applications Maritime Surveillance: Oil Spill Monitoring Provide information about oil slick locations and identification of faulty ships oil slicks ship

8 Oil Spill Monitoring: Coverage Requirements Coverage of areas of interest every 24 hours, at 25 m resolution Areas of Interest: Atlantic Great Lakes Pacific Potential Growth Labrador Coast Eastern Arctic Beaufort

9 Provides sea-ice cover maps for maritime navigation Operational sea-ice services are the largest near-real time users of SAR information in the world Key Applications Sea-Ice Monitoring

10 North American Ice Service: Coverage Requirements Coverage of areas of interest every 24 hours, at 100 m resolution (southern latitude coverage could be slightly less frequent)

11 Key Applications Disaster Management Provide early warning and operational support for disaster management such as floods and hurricanes Provides situational awareness of evolving situations (during bad weather and in remote areas) Provides intelligence information during humanitarian crises

12 Key Applications InSAR Surface Change Monitoring Frequent monitoring of geohazard-prone areas (e.g., earthquakes, volcanoes, landslides, subsidence) Mapping of ice motion and permafrost changes for climate change monitoring Coastal change monitoring Monitoring of wetlands and other critical ecosystems Crop monitoring

13 SAR Constellation Configuration CSA is developing two options for the SAR Constellation: A three-satellite constellation provides once daily Canadian coverage at 50m resolution Constellation of six satellites 10 min apart A six-satellite constellation provides twice daily Canadian coverage at 50m resolution Data analyzed in near-real time and following satellites tasked to image target at 5m resolution 50 min coverage of east Atlantic

14 Satellite Characteristics Rigid Panel Antenna No/Yes deployable structure? Antenna Size: 5 x 1.89 (no deployable) Extended Canadian Small-Sat bus (< 1100 kg) Compatible with Dnepr fairing (for design) Deployable antenna concepts: - Single-hinge - Mini R-2 Deployed 9170 mm AC1 : 4 panels - 8 columns - 24 rows T/R Modules Stowed for launch 1030 mm 2290 mm Orbit height Inclination Resolution Swath Width Imaging Time Polarization NESZ Repeat Orbit Cycle Lifetime 600 km m km 12 min/sat/orbit single & dual-pol for 1 sat -22 db 12 days 7 years

15 SAR Constellation Beam Modes ScanSAR (multi-beam) Stripmap

16 SAR Constellation Configuration InSAR Capabilities Satellites fly in the same orbital plane at altitude of 600 km Satellites follow each other with a time separation of ~ 32 min (3 sats) or ~ 16 min (6 sats) provide the coverage of ~ 1000 km over ocean (maritime surveillance) using ScanSAR mode 12-day repeat-orbit cycle for each satellite Formation of InSAR data pairs having a 4-day (3 sats) or 2-day (6 sats) time span

17 InSAR Capabilities Orbital Requirements Differential InSAR applications require small perp. baselines Common orbital tube of about 100 m in diameter for all satellites in the constellation relative requirement due to the drift of the tube Allows only short-term D-InSAR measurements Small ground track repeat for the entire constellation configuration absolute requirement Allows long-term D-InSAR and PS-InSAR measurements

18 InSAR Capabilities Beam Mode Requirements Repeat-pass stripmap InSAR high+resolution mode ~ 90% bandwidth overlap in azimuth and range Repeat-pass Scan-InSAR mapping mode Synchronization of the azimuth scanning pattern: Small number of bursts having a long duration (e.g., 4-5 sub-swaths = km swath width) High timing, position, and pointing accuracy

19 Timeline RADARSAT-1 ENVISAT RADARSAT-2 SAR Constellation-1 SAR Constellation-2 SAR Constellation »

20 International Partnerships CSA is currently exploring a range of potential partnerships, in particular to: Expand the ground network (i.e., increased command time and greater global coverage area Add capability to the constellation (e.g., automated ship identification) Add satellites to the constellation (objective: 6 satellite constellation) Identify potential infrastructure synergy (e.g., launch capability, ground segments) Partnership discussions include ESA, Norway and Finland, and will be extended during Phase A