Status of Meteosat Third Generation (MTG) Pre-Phase A System Architecture Studies

Transcription

1 Status of Meteosat Third Generation (MTG) Pre-Phase A System Architecture Studies Paolo Bensi, Earth Observation Future Programme Department European Space Agency

2 Planning: Meteosat Third Generation (MTG) 2015: NOMINAL NEED DATE FOR MTG : PHASE C/D DEVELOPMENT/ON-GROUND TEST OF MTG SYSTEM : PHASE B COORDINATED ESA & EUM PREPARATORY PROGRAMMES Approval of EUMETSAT and ESA MTG development programmes : MTG PHASE A STUDIES FOR SELECTED MISSION CONCEPTS (critical technologies pre-developments) : USER CONSULTATION PROCESS & PRE-PHASE A STUDIES PHASE 2: PRE-PHASE A STUDIES, EVALUATION/PRE- SELECTION OF MISSION CONCEPTS : PHASE 1: HIGH LEVEL USER NEEDS & PRIORITIES AGREED, PREPARATION OF PRE-PHASE A STUDIES

3 Pre-Phase A System Architecture studies ALCATEL ALENIA SPACE 2 Parallel Studies 14 months duration EADS ASTRIUM GmbH Requirements and Concepts Detailed Analysis and Definition Requirements & Trade-off tree Observation Payload Non Observ. Payload Selection mission / system Architecture (s) concepts Spacecraft & Launcher Candidate Concepts Characterisation Mission & Operations G/S concept Data Flow KO October 2004 v Mid-Term Review (MTR) Mar/Apr nd MTG UCW Locarno v Programmatic Aspects Wrap-up Architecture Consolidation and Justification System Update Planning & ROM estimates Critical Areas Mission Architecture Review (MAR) Sep/Oct 2005 In progress Close-out: Nov/Dec 2005

4 MTG Observation Missions Requirements λ: spectral range/channels; Δx: spatial resolution at sub-satellite point (SSP); BRC: basic repeat cycle FDHSI HRFI LI IRS UVS BRC Full Disk: 10 min 6x18 deg: 10/3 min 6x18 deg: 5 min 6x6 deg: 5/3 min 16 deg shifted N 10-3 sec Full Disk: 30 min 6x18 deg: 10 min 18x6 deg: 30 min 6x6 deg: 10 min λ 15 core channels in the range μm FD-OPT1: 4 channels O 2 absorption band ( μm) FD-OPT-2: 4 channels CO 2 absorption band ( μm) FD-OPT-3: 2 channels Aerosol/true colour imagery ( μm) 5 channels in the range μm 1 channel in the neutral Oxygen line (774.4 nm) bandwidth: 0.34 nm 9 bands in the range 4-15 μm. Synchronous imaging (sub-pixel characterisation): 1 VIS channel (0.5 km Δx) + 2 IR channels (1 km Δx) 10 bands in the range nm. Polarisation measurements along two orthogonal planes for two bands in the range nm or polarisation insensitive instrument (TBC). 3 bands in the O2 absorption band ( nm) Δx VNIR-SWIR: 1 km MWIR-TIR: 2 km VNIR-SWIR: 0.5 km MWIR-TIR: 1 km 10 km (over Europe) μm: 3 km μm: 6 km 6 km

5 From MOP to MTG MOP MSG MTG 1 observation mission: -MVIRI: 3 channels -Spinning satellite 2 observation missions: - SEVIRI: 12 channels - GERB - Spinning satellite 5 observation missions: - HRFI: 5 channels - FDHSI: 22 channels - Lightning Imager - Infra-Red Sounder -3-axis stabilised satellite(s) UVS coordinated with GMES Sentinel 4

6 System Concept Selection at MTR The following concept was selected for detailed analysis: Implementation of the imaging mission through the combined imager 1 imager instead of 2 on each satellite Simpler satellite configuration, reduced launch mass Significant cost savings (space segment/launcher) Payload accommodation (Combined Imager, IRS, LI) on multiple satellites Flexible system deployment and development approach Decoupling of higher risk sounding mission from the higher priority imaging mission Reduced complexity of key platform subsystems LI IRS HRFI FDHSI Combined Imager Combined Imager

7 MAR status Combined Imager 10 min. FD coverage (3.3 min LAC) 15 core channels (22 with options) 250 Kg 250 W Data Rate 50 Mbs (all options) Active cooling (driven by LW channels) 2 axes scan mechanism Entry Baffle Calibration Slot Earth face E/W Face N/S Face Baseplate Development Issues Detector arrays for the IR (LWIR) channels Scan Mechanism (complexity, lifetime) Cryo-coolers Optical elements (coatings, filters) Solar inputs effects (thermo-elastic deformations -> mission availability)

8 Telescope Optics MAR status Infrared Sounder Two instrument concepts analysed. Final selection still open Fourier Transform Spectrometer (FTS) Dispersive Spectrometer (DS) Collimating optics Michelson interferometer Mecanism Wavelength λ 0 Wavelength λ = λ 0 Band-pass filter Cold stop Detector array Imaging optics Slit opd = time Dispersive system Spectral sample λ 0 Detector array Step and Stare scanning Pushbroom scanning in EW direction 256 x 256 FPA at 6.5 sec dwell time Array size depends on band

9 MAR status Infrared Sounder E/W Face Earth face N/S Face Baseplate DS FTS Kg Kg 350 W W (1) 400 Mbps 3 Gbps (2) Active cooling (driven by LW channels) 2 axes scan mechanism (1) Depending on level of data processing and implementation (instrument/dhss) (2) Raw Instrument data rate before processing

10 MAR status Infrared Sounder Development Issues LWIR detectors array requires major pre-development (in different direction for the DS and the FTS) interferometer design (FTS), gratings (DS) Processing loads (FTS) Cryo-coolers Scan Mechanism (but driven by the combined imager) Solar inputs effects (thermo-elastic deformations -> mission availability) Preliminary Concept Assessment The engineering challenges are different between the DS and FTS concepts but of the same level of complexity at instrument level; The FPA array/cooler technologies require development for both DS and FTS but in different directions DS shows better radiometric performances for most bands whereas FTS seems better for LWIR bands; Spectral calibration requirements more constraining for the DS concept FTS instrument is more difficult to accommodate (data rate, pointing stability)

11 MAR status Lightning Imager 4 cameras 16 deg coverage (shifted N) 160 mm aperture 100 Kg W Data Rate 100 kbps radiator telescope baffle bench Development Issues prox. el. Not a small instrument, current concept based on reduced DE performances (DE>90% from 6 mj.m-2.sr-1 ) APS detector with smart pixel (extraction of lightning flash events) and narrow band filter (160 mm) are technologies to be developed Lightning flash models (at signal level) are essential for assessing the spatial and temporal coupling of the flash event with the detection process. Different assumptions have a significant impact on the instrument sizing

12 MAR status Space Segment L-band antenna North or South Main Body Deep Space IR-Sounder Lightning Imager UHF patch Combined Imager X-Band Antenna Y S-Band Antenna Xs X Nadir Launch Direction Zs Earth Ys Imaging Satellite (MTG-I) Sounding Satellite (MTG-S) Z Payload accommodation on two satellites: MTG-I (CI, LI, DCS) and MTG-S (IRS DS/FTS) Common S/C bus except communication payload and Data Handling, heritage from Telecom buses Launch mass: 3+ tons Power: 1+ kw PDT: L/X band for MTG-I, X/Ku band for MTG-S (on-board processing, DS/FTS selection) Launchers: Soyuz (3t), Ariane 5 S band TT&C

13 MAR status Space Segment MTG Satellite concept Main Features AOCS concept heritage from recent telecom development with improved sensor performances CPS for orbit acquisition and station keeping, EPS options for wheels unloading (and possibly N/S S/K) Asymmetric solar wing and 2-yearly yaw flip (instrument thermal control) High thermo-mechanical stability to minimise thermo-elastic distortion in orbit and particularly at eclipse transitions Micro-vibration impacts (Reaction wheels, active coolers) on observing missions performance to be analysed in details in the coming development phases

14 MAR status System deployment assumptions 8 satellites (2 MTG-I nominal + 2 MTG-I back-up; 2 MTG-S nominal + 2 MTG-S back-up) to cover the required mission lifetime (15 years + 5 years extension) Phased deployment approach (first MTG-S two years after the first MTG-I) to cope with the critical IRS development schedule and to provide programmatic flexibility 1-year commissioning MTG-I satellite MTG-S satellite Earliest date Latest date

15 MAR status Ground Segment Sounder satellite Imager satellite 0.6 to 1 deg ITM (X-band) TT&C (S-band) ITM (L-band) TT&C (S-band) Primary ground station - Tracking, Telemetry & Command (TTC) - Observation and DCP data acquisition - Level 0 processing - Back-up control centre Meteo data providers GOS partners Core facility (Darmstadt) Data Processing & Control Quality Control Center Facility Data Dissemination Facility Back-up ground station(s) SAF s - Level 2 processing Archive And on-line user services Terrestial network Non real time users Real time users

16 MAR status Conclusion The pre-phase A studies have identified suitable instrument/system concepts for the implementation of the MTG system, based on the present definition of user/mission requirements The mission is ambitious and demanding, major technology pre-developments are required (partially already initiated by ESA) Phased system development and deployment approach will mitigate the risk in compliance with the MTG mission priorities Programmatic inputs to be analysed soon. Affordability consideration will probably drive the consolidation of mission/system requirements applicable to the coming feasibility studies at phase A level The operational deployment of the MTG imagery mission by 2015 is judged feasible but challenging. MTG technical and programmatic requirements to be consolidated soon in line with the objective of starting Phase A and major predevelopments by 2006