1.
Emergency Response
For further information please visit:
ESA GMES website EC GMES website
www.esa.int/gmes www.ec.europa.eu/gmes We care for a safer world

2.
The Sentinel-1 Mission and its
Application Capabilities
Ramón Torres
GMES Sentinel-1 Project Manager
ESA - ESTEC
24 July 2012 We care for a safer world

3.
Presentation Outline
• Mission Objectives and Requirements
• Key Mission and System Facts
• Acquisition modes and performance
• Observation Strategy
• Observation Scenario
• Applications
• Conclusions
3

4.
Mission Objectives and Requirements
• Provide routinely and systematically SAR data to GMES Services
and National services
 Marine Monitoring (e.g. oil spill, sea ice)
 Land Monitoring (e.g. land cover, surface deformation)
 Emergency Response
 Climate Change (e.g. Polar caps incl. ice shelves and glaciers)
 Security (e.g. marine surveillance and ship detection)
• Provide C-band SAR data continuity of ERS/ENVISAT type of
missions at medium resolution (10 m and lower)
• Greatly improved coverage and revisit (i.e. as compared to
ENVISAT)
• Conflict-free operations (wide swath and dual-pol modes)
• High system availability (SAR duty cycle and data latency)
• Data quality similar or better than ERS/ENVISAT (e.g. equalized
performance across the swath) We care for a safer world

5.
Key Mission Facts
• Constellation of two satellites
(A & B units)
• Near-Polar sun-synchronous
(dawn-dusk) orbit at 693 km mean
altitude
• Both S-1 satellites are in the same
orbit (180 deg. phased in orbit)
• 12 days repeat cycle (1 satellite), 6
days for the constellation
• 7 years design life time with
consumables for 12 years
• Launch of Sentinel-1A October Prime contractor: Thales Alenia Space,
2013. Sentinel-1B will be ready for Italy
launch in the first half of 2015 Instrument responsible: EADS Astrium,
subject to EC funding Germany
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6.
Key System Facts
• C-Band SAR instrument
operates at centre frequency of
5.405 GHz
• On-board data storage capacity
(mass memory) of 1400 Gbit
• Two X-band RF channels for
data downlink with 2 X 260 Mbps
• On-board data compression
using Flexible Dynamic Block
Adaptive Quantization
• Optical Communication Payload
for data transfer via laser link
with the GEO European Data
Relay Satellite (ERDS) system
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7.
SAR Acquisition Modes
46o
Sentinel-1 SAR can be operated in
19o
4 exclusive measurement modes with
different resolution and coverage
Polarisation schemes for IW, EW & SM:
45o • single polarisation: HH or VV
30o
• dual polarisation: HH+HV or VV+VH
Polarisation scheme for WM: HH or VV
46o
19o
SAR duty cycle per orbit:
• up to 25 min in any of the imaging
modes
23o
• up to 74 min in WM
36o
IW: main mode of operation satisfying most
of user and services
WV: continuously operated over open ocean
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8.
SAR Mode Performance
Mode Access Single Look Swath Width Polarisation
Angle Resolution
Interferometric > 25 Range 5 m > 250 km HH+HV or
Wide Swath deg. Azimuth 20 m VV+VH
Main
Wave mode 23 deg. Range 5 m > 20 x 20 km HH or VV modes for
and Azimuth 5 m Vignettes at operations
36.5 deg. 100 km
intervals
Strip Map 20-45 Range 5 m > 80 km HH+HV or
deg. Azimuth 5 m VV+VH
Extra Wide Swath > 20 deg. Range 20 m > 400 km HH+HV or
Azimuth 40 m VV+VH
Image Quality Parameters for all Modes (worst case)
Radiometric accuracy (3 σ) 1 dB
Noise Equivalent Sigma Zero -22 dB
Point Target Ambiguity Ratio -25 dB
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Distributed Target Ambiguity Ratio -22 dB

9.
Sentinel-1 Observation Strategy
Based on optimum use of SAR duty cycle (25 min/orbit)
 satisfies the GMES user/service requirements (i.e. resolution, swath width,
polarisation)
 increases revisit time and coverage
 enables build-up of long-term data time series
 provides high level of automation for mission planning
 allows pre-defined operations
 minimizes potential conflicts during operations, considering
various constraints (e.g. mode transition times, X-band switches)
• Over land and maritime shipping routes: IW is pre-defined mode
• Over Polar areas (i.e. sea ice): IW mode is pre-defined mode (EW could
be used if decrease in radiometric resolution is acceptable)
• Emergency observation requests may alter the pre-defined observation
scenario: use of e.g. SM mode
• Over open ocean: WV mode is continuously operated We care for a safer world

10.
Sentinel-1 Observation Scenario
Sea-ice monitoring
services in the North
Hemisphere
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11.
Sentinel-1 Observation Scenario
Sentinel-1 Real-Time (10min)
requirements from EMSA
(CleanSeaNet Oil Spill
Monitoring Service)
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12.
Sentinel-1 Observation Scenario
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13.
Sentinel-1A Observation Scenario
Average Revisit Time S-1A Satellite Average Revisit Time with S-1A + S-1B Satellites
S-1A Satellite S-1A + S-1B Satellites
Complete global After 12 days After 6 days
coverage
Ice MTZ Europe Canada Rest of Ice MTZ Europe Canada Rest of
Land Land
Number of 1-9 1-6 1-5 1-4 1-6 2-18 2-12 2-10 2-8 2-12
acquisitions (range
from - to)
Average Revisit 8,0 3,7 5,5 8,2 9,9 5,0 1,9 2,7 4,1 4,9
Time [day]
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14.
Sentinel-1 Applications: Ship Detection
100m
Smaller ships
30m
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15.
Sentinel-1 Applications: Dyke Monitoring (INSAR)
– Estimated sea-level rise impacts in the Netherlands and Germany.
– 0.65 m (dark blue) and 1.3 m (light blue)
Courtesy Hansje Brinker BV We care for a safer world

16.
Sentinel-1 Applications: Land cover classification
Based on multi-temporal scene
acquisitions
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17.
Sentinel-1 Applications: Ice Classification
– ENVISAR ASAR image
separating thinner, more
navigable first year ice
from the hazardous,
stronger and much
thicker multi-year ice.
Courtesy of the Canadian Ice
Service.
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18.
Applications Performance Prediction
S1 Level-2 Product Resolution Performance Units
Subsidence Rate 5 x 20 m2 1.3/1.3 mm/year
Land Cover 30 x 30 m2 90/75 % correct
Classification (2 dB classification
contrast )
Forest Non-Forest 30 x 30 m2 98.6/75 % correct
Classification classification
Soil Moisture 100 x 100 m2 0.8/1.2 volume %
Flood Mapping 30 x 30 m2 93/79 % correct
classification
Snow Cover 30 x 30 m2 80/75 % correct
Classification classification
Ship Detection 5 x 20 m2 20/40 ship length (m)
Sea Surface Wind Speed 100 x 100 m2 0.4/0.8 m/s
Sea Surface Currents 5 Hz 30/30 cm/s We care for a safer world

19.
Conclusions
• Sentinel-1 is the GMES European Radar Observatory that will ensure
the continuation and improvement of SAR operational services of
medium- to high-resolution applications
• Sentinel-1 will become one of the main data sources for the six
GMES service themes identified by the European Commission for
which it will support the provision of operational services based on
Earth observation data: Emergency Response, Marine Monitoring,
Land Monitoring, Atmospheric Monitoring, Security, and Climate
• The System is optimised to a main mode of operation that features
both a wide swath (250 km), high geometric resolution (5 × 20 m)
and high radiometric accuracy (1dB 3σ), allowing imaging of global
landmasses, coastal zones, sea ice, polar areas, and shipping routes
at high resolution, in a repeat cycle of 12 days
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20.
Conclusions
• Sentinel-1 is designed to respond to emergency requests to support
disaster management in crisis situations but otherwise works in a pre-
programmed conflict-free operation mode that will ensure the
reliability required by operational services and will create a consistent
long-term data archive for applications based on long time series
• The Spacecraft are being built by an industrial consortium led by
Thales Alenia Space (Italy) as the Prime Contractor, while Astrium
GmbH (Germany) is responsible for the C-band Synthetic Aperture
Radar (CSAR) payload, which incorporates the central radar
electronics subsystem developed by Astrium Ltd. (UK)
• The Sentinel-1A Spacecraft is scheduled to be launched in October
2013 with Soyuz from Kourou
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