Ramon Torres

SENTINEL-1 SYSTEM CAPABILITIES AND APPLICATIONS

The paper provides an overview of the Copernicus Sentinel-1 system capabilities and applications. In particular, the characteristics of the Sentinel-1 SAR imaging modes and their key performance parameters are described. In addition, the Sentinel-1 SAR interferometry (InSAR) capabilities, especially for TOPS InSAR and the strategy for maintaining the orbital baseline as well as the requirements for TOPS image co-registration are discussed.

Sentinel-1 mission status

Sentinel-1A has been launched from Kourou on a Soyuz rocket on 3rd April 2014. The second satellite Sentinel-1B is planned to be launched first half of 2016. The In-Orbit Commissioning phase was completed on 23 September 2014, followed by the so-called operational qualification phase (ramp-up). This ramp-up operations phase is a phase during which the capacity of the overall system, including the ground segment operations, is progressively increased, together with the gradual release of the operationally qualified products. The ramp-up phase is being completed at the time of writing this paper (end May 2015); at this stage the routine operations are starting. The Full Operation Capacity (FOC) of the mission will be reached once the In-Orbit Commissioning phase of Sentinel-1B and the subsequent constellation operational qualification phase will have been completed, indicatively by end 2016. The paper provides high-level information on the ongoing mission operations, at the time of the ramp-up phase completion. It described at high level the system operations, incl. ground segment operational activities, as well as some user data access statistics. It presents few examples of mission results achieved during the first year of Sentinel-1A in orbit, in some key application domains.

ASAR instrument performance and product quality status

This paper presents the main characteristics of the advanced synthetic aperture radar (ASAR) instrument on board ENVISAT, ASAR products, the challenges in the ASAR calibration and product validation, the methodology used to perform the sensor performance monitoring and product calibration based on the special ASAR features and dedicated calibration sites and finally a summary on the product quality status will also be provided.

Sentinel-1 system overview and performance

The paper provides an overview of the GMES Sentinel-1 system characteristics including the SAR imaging modes and their key performance parameters, the SAR interferometry capabilities, and the specifics of related attitude and orbit control modes (i.e., roll steering mode and zero-Doppler steering mode). Furthermore, the paper outlines the planned Sentinel-1 commissioning phase activities related to the in-orbit SAR system end-to-end performance verification and calibration.

The Sentinel-1 mission and its application capabilities

The ESA Sentinels constitute the first series of operational satellites responding to the Earth Observation needs of the EU-ESA Global Monitoring for Environment and Security (GMES) programme. The GMES space component relies on existing and planned space assets as well as on new complementary developments by ESA. This paper describes the Sentinel-1 mission, an imaging synthetic aperture radar (SAR) satellite constellation at C-band. It provides an overview of the mission requirements, its applications and the technical concept for the system.

Sentinel-1A and Sentinel-1B CSAR status

The ESA Sentinels constitute the first series of operational satellites responding to the Earth Observation needs of the EU-ESA Global Monitoring for Environment and Security programme. The GMES space component relies on existing and planned space assets as well as on new complementary developments by ESA. In particular, as part of the GMES space component, ESA is currently undertaking the development of 3 Sentinels mission families. Each Sentinel is based on a constellation of 2 satellites in the same orbital plane. This configuration allows to fulfil the revisit and coverage requirements and to provide a robust and affordable operational service. The launch of the 2nd satellite is scheduled 18 months after the launch of the 1st spacecraft of the constellation. The lifetime of the individual satellite is specified as 7 years, with consumables allowing mission extension up to 12 years. The lifecycle of the space segment is planned to be in the order of 15-20 years. The strategy for Sentinel procurement and replacement over this period is being elaborated, but will likely result in a need for 4-5 satellites of each type if the desired robustness for the service that GMES will provide is to be achieved. This paper will describe the operational and observational capabilities of the Sentinel-1 mission based on the user requirements, including potential emergency requests. An example of a pre-defined mission timeline for each and every cycle will be given.

C-SAR instrument design for the Sentinel-1 mission

The ESA Sentinels constitute the first series of operational satellites responding to the Earth Observation needs of the EU-ESA Global Monitoring for Environment and Security (GMES) programme. The GMES space component relies on existing and planned space assets as well as on new complementary developments by ESA. This paper describes the Sentinel-1 mission, an imaging synthetic aperture radar (SAR) satellite constellation at C-band. It provides an overview of the mission requirements, its applications and the technical concept for the system.

Sentinel-1B LEOP and commissioning

Sentinel-1A, the first component of the Copernicus Space Segment developed by the European Space Agency, has been launched 3 April 2014. The LEOP Phase is expected to last three days where all subsystems and the SAR instrument will be checked. It is immediately followed by the three-month Commissioning Phase that will include the in-orbit Calibration and Characterisation, and the verification of the satellite, in order to deliver a full functional and well performing satellite to the mission operations. This paper will present the LEOP and Commissioning activities in progress, and the status of Calibration, Characterisation and Verification activities of the Commissioning in place.

Sentinel 1 evolution: Sentinel-1C and -1D models

The paper provides an overview of the evolution of the Copernicus Sentinel-1 mission, which is part of the Copernicus European Earth Observation program. Following the successful launch and in-orbit Commissioning of Sentinel-1A in 2014 and Sentinel-1B in 2016, ESA is currently developing the Sentinel-1 C and D models. The paper addresses the expected improvements in system robustness and performance. In addition, it discusses the main characteristics of the Automatic Identification System (AIS) instrument to augment the SAR payload data for ship marine traffic applications and the Optical Communication Payload (OCP) for payload data downlink via inter-satellite laser-link with the European Data Relay System (EDRS). Finally, the design of Sentinel-1C and Sentinel-1D incorporates novel solutions that will make both satellites fully compliant with the latest Space Debris code-of-conduct and the required casualty risks at re-entry.

Sentinel-1 SAR system and mission

The paper provides an overview of the Copernicus Sentinel-1 mission, which includes Sentinel-1A (S-1A) and Sentinel-1B (S-1B) satellites, and the characteristics of its SAR system. Sentinel-1 uses pre-programmed SAR mode operations to provide a high revisit frequency and systematic global SAR image coverage. This is mainly based upon the operational use of the novel TOPS (Terrain Observation with Progressive Scans in azimuth) SAR imaging mode. In particular, we present results of the SAR system performance analysis focusing on the instrument stability and the achieved radiometric accuracy, as well as the Noise Equivalent Sigma Zero (NESZ). In addition, we discuss the cross-S-1A/S-1B SAR Interferometry (InSAR) performance considering the effects of burst synchronization and SAR antenna pointing on the achievable common Doppler bandwidth. Results of differential cross interferograms are presented showing the coseismic surface displacement caused by the central Italy earthquake.