The CryoSat-2 spacecraft is one of the Opportunity missions of the ESA Living Planet programme. It is currently operated by the European Space Operations Centre, in Darmstadt. The Mission objective is to provide a global continuous measurements of the ice cover variations on the Polar caps and continental ice sheets plus other areas of land ice which is being achieved thanks to the use of its multi-mode interferometer radar, SIRAL. Additionally, CryoSat-2 data is being used to support the Oceanography community with respect to the long term sea level monitoring.
In April 2019, Cryosat-2 will have achieved nine years of operations, covering six-months of commissioning and the follow on routine operations, including the completion of the nominal mission and the start of the extended routine phase. Overall, the mission has proven to be very successful and the spacecraft overall performance very reliable.
The poster provides an overview of the CryoSat-2 current status, including the currently “active” anomalies, i.e. those which have not already been solved on-board, and their potential impact on the mission. A brief explanation of the satellite operations performed in the routine phase will be provided. Special operations in support of the mission performance and characterisation and also as a consequence of anomalies will be presented. An outlook on the future of the satellite will be included with respect to the operations concept, i.e. which activities are already being performed to mitigate the aging of the satellite in order to ensure the mission continuation throughout the mission extension phase and beyond.
In order to support the further continuation of the mission a number of changes to the ground segment have been undertaken too. These will be described, including the methods used to mitigate impact of the changes of the ground segment on the satellite operations and also the benefit that these changes will bring to the longevity of the mission. The additional layer autonomous notification layer for on-board anomalies will be described and the benefit with respect to science data return highlighted.
Special attention will also be given to the gains obtained by exploiting all possible synergies with the Swarm mission in terms of ground operations.

Area C - Board 299

Swarm is the magnetic field mission of the ESA Earth Observation program composed by three satellites flying in a semi-controlled constellation. Its history in-orbit began in the after-noon of the 22nd November 2013, when the three identical spacecraft separated perfectly from the upper stage of the Rockot launcher at an altitude of about 499 km. Control of the trio was immediately taken over by the Flight Operations Segment (FOS) established at the ESA’s Space Operations Centre (ESOC) in Darmstadt, Germany. Following the successful completion of the Launch and Early Orbit Phase (LEOP), commissioning was concluded in spring 2014 and precious scientific data have been provided since then.

Due to the valuable contribution provided by the Swarm mission, its in-orbit lifetime (phase E) has been extended from the maximum foreseen of six years, four nominal plus two of po-tential extension, to a period covering at least one full solar cycle, i.e. twice as expected. This raised the need to identify the best strategy to support the operations in a scenario much long-er than foreseen.

Some of the systems involved were not designed or sized to satisfy the mission requirements for such an extended period and the natural obsolesce of part of the underlying technologies started to be a concern. An overall upgrade of the Swarm Mission Control System (SMCS) was therefore one of the key aspects to support the mission extension for what concerned the Flight Operations Segment (FOS).

An overview of the evolution of the Swarm Mission Control System (SMCS) in terms of con-cept and implementation will be presented, together with a brief description of the solution selected for the upgrade. Drivers and effort for a full migration of an in-use Mission Control System are described with special focus on the strategies adopted to avoid any impact on data return, to minimise disruption of on-going operations and to reduce changes in the inter-faces between the Flight Operations Segment (FOS) and its external entities.

The reasons why the porting of such a complex and articulated system for a flying mission is a challenge will be presented through the analysis of the areas involved: Applications Software, Hardware, Operating-System, Data Storage and supporting tools.
Emphasis will be given to
• the different validation phases of the Multi-Satellite Application Software (SCOS-2000 Release 6);
• the strategy adopted for the migration of the data;
• the update of the Flight Operations Segment (FOS) interfaces and the cooperation with the entities involved;
• the adaptation of the procedures included in the Flight Operations Plan (FOP) and the training of the operational team.

Details about the parallel coexistence between the original and the new system during the different testing phases will be provided, together with the description of the approach cho-sen to implement the final roll-out on the operational environment.

To conclude, a parallel evaluation of the benefits of the adopted solutions (e.g. in terms of costs reduction, flexibility and technological innovations) with respect to the risks linked to substituting a well proven and running system will be provided. All that to anticipate the capability of the new Swarm Mission Control System to support not only the current extension but potentially many more with a minimum number of further adaptations.

Area C - Board 300

This paper will discuss in detail the current status and results concerning the implementation of an end-to-end (E2E) performance simulator for the BIOMASS mission [1].
BIOMASS is the 7th Earth Explorer Mission [2] of the European Space Agency (ESA), approved for full implementation in February 2015 and to be launched in 2022. As primary objective, BIOMASS will measure in a consistent manner the global distribution of the above-ground forest biomass and its changes for improving resources assessment, carbon accounting and carbon models [3]. To achieve this, the mission is based on a P-band (central frequency 435 MHz) Synthetic Aperture Radar (SAR) with 6 MHz bandwidth operated on a down/dusk orbit in a side-looking geometry with a 3-4 day repeat-pass. The satellite will systematically acquire fully-polarimetric data in an interferometric mode over (almost) all major forested areas on the globe. The inversion methodology is then based on backscatter intensity measurements and interferometric coherence measurements at different polarizations. By doing so, the sensitivity of the backscatter intensity measurements to biomass at low biomass levels (<200Mgr/ha) will be combined with the sensitivity of the interferometric coherence measurements to vertical forest structure at high(er) biomass levels (>100Mgr/ha). Additionally, secondary objectives such us the monitoring of glaciers, ice sheets and under-vegetation topography and the mapping of the subsurface geology in desert and arid areas will be also considered.
In order to support the instrument design, the calibration algorithms consolidation and the mission performance verification during the Phases B2, C, D and E1, a complete E2E chain consisting of the BEEPS Front End (BEEPS-FE) [5] and the Ground Processor Prototype (GPP) [6], which represents the Space Segment and the Ground Segment of the BIOMASS mission, respectively, is currently being developed. The demonstrator represents an evolution of the previous end-to-end chain (BEES) developed during the Phase A activities [4]. However, BEEPS-FE will simulate raw data which later on will be focused by the GPP, producing up to simulated Level 1a/1b products.
Focusing first on the raw data simulation and trying to make the most profit out of it, BEEPS-FE needs to go beyond the mere radiometric sensitivity analysis and shall reinforce the understanding of the main error sources (especially, instrument- and platform-related as well as environmental errors, including ionospheric disturbances and RFIs) and allow for the quantification of their impact on the mission performance. On the other side, the GPP shall be considered as the main reference for the development and validation of the operational processor, to be implemented within the Payload Data Ground Segment, and support both the processing and the calibration algorithms.
A complete overview of the architecture solution for BEEPS will be provided in the full-paper, including a functional description of the key modules, and the up-to-date E2E results will be reported as well.

References
[1] “BIOMASS – An Earth Explorer to observe forest biomass. Report for Mission Selection”. ESA Technical Report, ESA SP-1324/1, May 2012.
[2] J. Bezy et al.: “ESA Future Earth Observation Explorer Missions,” in Proc. of the IEEE Geoscience and Remote Sensing Symposium (IGARSS), pp. 212–215, 2007.
[3] “BIOMASS –To observe global forest biomass for a better understanding of the carbon cycle. Report for Assessment”. ESA Technical Report, ESA SP-1313/2, Nov. 2008.
[4] P. López-Dekker et al: “BIOMASS End-to-End Mission Performance Simulator”, in Proc. of the IEEE Geoscience and Remote Sensing Symposium (IGARSS), pp. 4249–4252, 2011.
[5] M.J. Sanjuan-Ferrer et al: “End-to-End Performance Simulator for the BIOMASS Mission”, in Proc. of the European Synthetic Aperture Radar Conference (EUSAR), pp. 1164-1168, 2018.
[6] P. Prats-Iraola et al: “The BIOMASS Ground Processor Prototype: An Overview”, in Proc. of the European Synthetic Aperture Radar Conference (EUSAR), pp. 919-924, 2018.

Area C - Board 301

The Sentinel-1 core ground segment allows all Sentinel-1 data to be systematically acquired, processed and distributed [1]. Within the core ground segment, the S-1 Mission Performance Center (MPC) is responsible for calibration, validation, quality control and end-to-end system performance assessment of the products [2]. The MPC includes expert teams for specific Calibration / Validation, quality control, algorithm correction and evolutions for the SAR processor both for Level 1 (images in SLC and GRD) and Level 2 (OCN / Ocean Wind, Swell and Radial Velocity) products.

The purpose of this presentation is threefold:

First, to present the organization of the MPC and the team covering both L1 and L2 experts, and how the QC/Cal/Val activities on Level 1 products benefits to the quality of the products delivered to the end users by illustrating the key quality parameters monitored by the MPC.

Second, to present the main evolutions of the SAR processing baseline for both Sentinel-1A and 1B since their respective start of operations (improved radiometric accuracy, improved noise annotation, global L2 productions…) and the planned evolutions. On those topics the members of the Expert Support Laboratories of the MPC, also attending to the workshop in specific sessions, will be able to directly interact with the users interested with specific topics.

Finally, to present how the Sentinel-1 product end-user can access the most up to date information on the Sentinel-1 status and performances and contact the MPC if they want to raise specific questions. This includes presentation of links to the appropriate documentation (IPF release note for S-1 product end users, Cyclic and Annual Performance reports, etc), web sites (QC Web Site, Sentinel Online, etc) and forum / social medias.

This presentation aims to complement potential presentation of the mission status by ESA and to provide contact points for the end users for requests on product performances.

[1] https://sentinel.esa.int/web/sentinel/missions/sentinel-1/ground-segment/core-ground-segment
[2] https://sentinel.esa.int/web/sentinel/missions/sentinel-1/ground-segment/core-ground-segment/pdgs

Area C - Board 303