SENTINEL 1 C-BAND SAR PAYLOAD All the space you need

SAR Antenna Subsystem (SAS) in
stowed configuration
Integrated Control Electronics (ICE) of
SAR Electronic Subsystem (SES)
All the space you need
SENTINEL 1 C-BAND SAR PAYLOAD
The Sentinel 1 Mission is part of the Global Monitoring for Environment and Security (GMES) initiative
whose overall objective is to support Europe’s goals regarding sustainable development and global
governance of the environment by providing timely and quality data, information, services and knowledge.
Sentinel-1 is a C-band radar imaging mission aimed at providing continuity for ERS and Envisat data products
to be used for operational services. In particular, Sentinel-1 is aimed at providing data to the sea ice zones
and the arctic environment, to surveillance of marine environment (wind speed, oil spill and ship detection),
to monitoring and mapping land surfaces, and mapping in support of humanitarian aid in crisis situations.
Astrium is Prime Contractor for the Sentinel-1 C-Band Synthetic Aperture Radar (SAR), which is composed
of a SAR Antenna Subsystem (SAS) and a SAR Electronic Subsystem (SES).
The SAR Antenna Subsystem (SAS) is developed and build by Astrium GmbH. It is a large foldable planar
phased array antenna, which is formed by a centre panel and two antenna side wings. In deployed configuration
the antenna has an overall aperture of 12.3 x 0.84 m. The antenna provides a fast electronic scanning capability
in azimuth and elevation and is based on low loss and highly stable waveguide radiators build in carbon fibre
technology, which are already successfully used by the TerraSAR-X radar imaging mission.
The SAR Electronic Subsystem (SES) is developed and build by Astrium Ltd. It provides all radar control, IF/
RF signal generation and receive data handling functions for the SAR Instrument. The fully redundant SES is
based on a channelised architecture with one transmit and two receive chains, providing a modular approach
to the generation and reception of wide-band signals and the handling of multi-polarisation modes. One key
feature is the implementation of the Flexible Dynamic Block Adaptive Quantisation (FD-BAQ) data compression
concept, which allows an efficient use of on-board storage resources and minimises downlink times.

7464tl apr © Astrium 2010, images © Astrium 2010, © ESA 2010
Customer European Space Agency/Thales Alenia Space
Mission Ocean, Ice and Land Monitoring
Orbit Polar sun synchronous orbit at 700km
Spacecraft PRIMA-type Platform
Payload C-band SAR
• Instrument mass: 930kg
• Instrument dimensions: 12.3m x 0.84m x 0.3m in deployed
configuration
• Instrument power consumption: 3.5kW
RF Characteristics • Centre frequency: 5.405GHz
• Bandwidth: up to 100MHz • RF peak power: 4.3kW
• Polarisation: HH-HV, VV-VH • Duty cycle: up to 12%
Measurement Modes • Stripmap mode
• Extrawideswath mode
• Interferometric wideswath mode • Wave mode
Mission Duration 7 years
Astrium Responsibilities • SAR Instrument Prime Contractor
• SAR Electronic Subsystem Contractor
Key Features:
To satisfy the need for the wide variety of data products of the Sentinel-1 mission, the C-band SAR Instrument
provides three radar imaging modes with dual polarisation capability (HH-HV, VV-VH) :
• Stripmap Mode (6 selectable swathes of 80 km each, 5 m x 5 m resolution)
• Interferometric Wideswath Mode (250 km swath, 5 m x 20 m resolution)
• Extra-Wideswath Mode (400 km swath, 20 m x 40 m resolution)
and one single polarised ocean mode (HH or VV) :
• Wave Mode (20 km x 20 km vignettes, 20 m x 5 m resolution)
The Wideswath modes are both implemented as ScanSAR modes with progressive azimuth scanning (TOPS)
to ensure an excellent and homogenous image quality over the complete swath. In all four measurement
modes a high sensitivity (nESZ