ESA s Earth Observation Lidar Missions and Critical Technology Developments

Transcription

1 ESA s Earth Observation Lidar Missions and Critical Technology Developments J.-L. Bézy European Space Agency Jean-Loup.Bezy@ esa.int ICSO Rhodes, Island, October October Slide 1

2 Acknowledgments Directorate of Earth Observation Programme: Yannig Durand and Roland Meynart Jérôme Caron, Arnaud Hélière, Martin Endemann, Alain Culoma, Olivier le Rille, Armin Loescher, Paolo Bensi Directorate of Technical & Quality Management: Michael Jost, Nick Nelms, Mustapha Zahir, Errico Armandillo Slide 2

3 Lidar Principles Doppler lidar Wind vectors Velocity = /2* f ADM-Aeolus Backscatter lidar Cloud vertical profile Aerosol vertical profile I T I R Frequency Extinction = I R /I T ATLID/EarthCA RE Differential absorption lidar Trace gases concentration Time Concentration = Log(I on /I off ) A-SCOPE WALES ACCURATE Wavelength Altimetry lidar Ranging Vegetation canopy distribution Range = c t/2 BepiColombo Time Slide 3

4 Current ESA lidar missions under development BepiColombo ADM-Aeolus EarthCARE Slide 4

5 Atmospheric Dynamics Mission-Aeolus Scientific objective: quantify global measurements of vertical wind profiles in the troposphere and lower stratosphere to improve the quality of weather forecasts, and to advance our understanding of atmospheric dynamics and climate processes. MISSION PARAMETERS Orbit: Sun-synchronous Altitude ~ 405 km Local time ~18:00 ascending node Mass: 1500 kg Power: 2.3 kw Mission life: 3 years PAYLOAD Doppler Wind Lidar (ALADIN) Slide 5

6 Atmospheric Dynamics Mission-Aeolus Measurement geometry Main Observation requirements PBL Troposphere Stratosphere Vertical Domain [km] Vertical Resolution Horizontal Domain [km] Global Profile Separation [km] 200 Accuracy HLOS [ms -1 ] Dynamic Range [ms -1 ] ± 150 Horizontal integration [km] 50 Slide 6

7 Atmospheric Dynamics Mission-Aeolus Mie, Fringe imaging receiver Measurement principle Rayleigh, Double edge receiver Slide 7

8 Atmospheric Dynamics Mission-Aeolus Instrument features The Flight Model of the Mie Spectrometer with the Fizeau etalon and the associated optics Transmitter (Nd:YAG) Wavelength Pulse energy Repetition rate Line width Duty cycle Transmit-receive Telescope Telescope diameter Telescope transm. (incl. obscuration) Transmitter beam divervence (full angle) Receiver Field-of-View (full angle) 355 nm 120 mj 100 Hz 30 MHz 42 % 1.5 m > 80 % 12 µrad 19 µrad Laser diode stack used to pump the master oscillator and the power amplifiers of the transmitter. Receiver Fizeau interferometer (Mie) Free Spectral Range Useful Spectral Range Fringe width (FWHM) Double Fabry-Perot (Rayleigh) Free Spectral Range Spacin Detector quantum efficiency 2.2 GHz 1.5 GHz 145 MHz 10.9 GHz 5.5 GHz > 80% Detection Front-end Unit with the Accumulation CCD The completed Aeolus 1.5 m transmit/receive SiC telescope Slide 8

9 Atmospheric Dynamics Mission-Aeolus Status Platform Integration completed and in storage Laser: testing in progress, some design issues still need to be resolved (alignment stability) Low pressure Oxygen environment to the majority of the high intensity laser optics. Operation in continuous mode Power Laser Head Slide 9

10 ADM-Aeolus: Airborne Campaigns Campaigns activities First results from 3rd airborne campaign Ground return compares good to DEM First Rayleigh winds compare qualitatively good to 2 µm wind lidar Reference 2 m LOS wind A2D Rayleigh LOS wind Slide 10

11 EarthCARE: Earth Clouds Aerosols and Radiation Explorer Mission Scientific objective: quantify aerosol-cloud-radiation interactions so to include them correctly in climate and numerical weather forecasting models. Instantaneous radiative flux with an TOA error of 10 Wm -2 MISSION PARAMETERS Orbit: Sun-synchronous Altitude : 393 km Local time : 13:45..14:00 descending node Mass: 2000 kg Power: 1.5 kw Mission life: 3 years PAYLOAD Backscatter Lidar (ATLID) Cloud Profiling Radar (CPR) Multi-Spectral Imager (MSI) Broad-Band Radiometer (BBR) Slide 11

12 EarthCARE: ATmospheric backscatter LIDar Main Observation requirements Cirrus Cirrus optical depth Mie copolar channel Rayleigh channel 0.05 Mie X- polar channel Backscatter sr -1 m -1 8 x x 10-5 Vertical resolution 100 m 300 m 100 m Required 10 km integration 50 % 15 % 45 % 40 km Measurement geometry Laser pulse Instrument sized to detect the weak signal from the thinnest radiatively significant cirrus cloud in daytime above dense cloud deck Sampling = 500 m Sampling = 100 m 20 km Atmosphere Horizontal sampling distance =100 m 0 km Averaging length = 10 km Time Signal Slide 12

13 EarthCARE: ATmospheric backscatter LIDar Measurement principle arbitrary unit Mie scattering contribution Rayleigh scattering contribution HSR filter transmission Relative frequency (GHz) arbitrary unit Relative frequency (GHz) arbitrary unit Relative frequency (GHz) UV (355 nm) Backscatter Lidar with High Spectral Resolution Receiver to separate Rayleigh (molecular) and Mie (cloud,aerosol) cross and copolarisation return Slide 13

14 EarthCARE: ATmospheric backscatter LIDar Instrument requirements Parameters Transmitter Wavelength Pulse energy Repetition rate Line width Receive Telescope Telescope diameter Receiver HSR Etalon Working Aperture Acceptance angle Overall finesse Peak transmission Bandwidth Free spectral range Background filter rejection Working Aperture Peak transmission Overall finesse Bandwidth Free spectral range Value 355 nm 30 mj 74 Hz 50 MHz 0.6 m 20 mm 0.78 mrad 8 > 87 % < 0.3 pm 2.4 pm 38 mm > 80 % pm 0.45 nm Capacitance stabilised HSR etalon have been developed and successfully assessed against environment loads. Slide 14

15 EarthCARE: ATmospheric backscatter LIDar Status: Preliminary Design Review completed Bi-static configuration Pressurised laser Slide 15

16 EarthCARE: ATLID pre-development ATLID Laser Source: Medium energy frequency tripled and stabilised Nd:YAG laser MO/PA architecture Parameters Output energy Optical optical efficiency PRF Performance 34 mj 8% [808 nm-355 nm] 100 Hz Spatial quality M 2 < 1.7 Boresight stability < ±41 µrad ptp over 10 min Pulse duration Longitudinal mode Pulse linewidth Spectral purity Frequency stability < 35ns Single < 50MHz 99% in 100MHz < 10MHz rms over 1.4 sec Oscillator: End pump; 8 mj, 15 % o-o Amplifier based on patented Innoslab concept: Slab crystal partially end-pumped from 2 sides Signal folded in single pass configuration with constant fluence: scalable output 85 mj with 21 % o-o Harmonic section: LBO crystals: efficiency < 50 % Slide 16

17 EarthCARE: ATLID pre-development ATLID Stacks: laser diodes manufacturers involved in the development of a stack optimised for a space application: long lifetime, high efficiency Parameters Requirements Wavelength ( ) nm Spectral width 2-3 nm Peak output power > 700 W Pulse width µs Repetition rate Hz Total efficiency > 50% Emitting area < 10 x 14 mm Divergence < 10 x 60 deg Polarisation Linear >95% Lifetime 10 billion shots Highly-Reliable Laser Diodes and Modules for Spaceborne Applications, E. Deichsel, Jenoptik, Session 4a Slide 17

18 A-SCOPE: Advanced-Space Carbon and Climate Observation of Planet Earth Mission Scientific objective: The observation of the spatial and temporal gradients of atmospheric XCO 2 with a precision and accuracy sufficient to constrain CO 2 fluxes within 0.02 Pg C yr -1 on a scale of 1000 x 1000 km 2. MISSION PARAMETERS Orbit: Sun-synchronous Altitude ~ 400 km Local time 06:00 descending node PAYLOAD Integrated Path Differential Absorption lidar (IPDA) Mass: ~ 1000 kg Power: ~ 1.7 kw Mission life: 3 years Slide 18

19 A-SCOPE: Advanced-Space Carbon and Climate Observation of Planet Earth Mission Main Observation requirements Value NIR (1.57 or 2.05 m) DIAL lidar for total column dry air CO 2 mixing ratio Geophysical product XCO 2 Random error [ppm] 0.5 Systematic error [ppm] 0.05 Coverage Horizontal Resolution observation Horizontal Resolution measurement Vertical resolution Global [km] 50 [m] 100 Total column Weighting function [-] = 2.05 m = 1.57 m Altitude [km] Slide 19

20 A-SCOPE: Advanced-Space Carbon and Climate Observation of Planet Earth Mission Instrument parameters Parameters 1.57 m 2.05 m Transmitter Pulse energy Repetition rate Frequency accuracy Linewidth Spectral purity Receive Telescope Telescope diameter FOV Detector QE NEP 50 mj 50 Hz 70 khz 50 MHz > m 0.47 mrad 55 mj 50 Hz 100 khz < 50 MHz > % 1.2 m mrad fw/hz fw/hz 0.5 Instrument design drivers: Low random error: 0.5 ppm wrt 380 ppm (0.13 % of DAOD) for ~ 350 measurements high laser power telescope aperture low detector noise maximize the on and off-lines pulses overlap on ground Very low systematic error: 10 % of random error for 1000 x 1000 km 2 laser spectral stability and knowledge laser spectral purity stability of power monitoring of emitted laser pulses stability and knowledge of the S/C pointing Slide 20

21 A-SCOPE: pre-development A-SCOPE laser sources: OPO-OPA at 1.57 m Parameters OPO-OPA Requirements Fiber laser Spectral band (um) PRF (Hz) Power (W) Energy per pulse (mj) Bandwidth (MHz) Spectral Stability (MHz) over 10 s Spectral purity in 1 GHz 99.94% 99.98% 99.9% Fibre laser at 2.05 m OPO-OPA at 2.05 m Slide 21

22 A-SCOPE: pre-development A-SCOPE APD detectors at 2.05 m HgCdTe: APD based on loophole junctions Amplifier based on CMOS TIA MCT hybridised directly onto the silicon chip InAlAs: Type-II superlattice heterojunction SAM structure MBE growth Current (A) Dark current Photocurrent T=200KMultiplication =2.1 m IV characteristics of Type-II APD Reverse Voltage(V) Multiplication Excess Noise factor Excess Noise Factor Parameters QE 70% Active area diameter Multiplication 150 m Excess noise 1.5 NEP 100 fw/hz 0.5 ] Bandwidth Gain stability Linearity 20 MHz 0.1 % rms (short term) 5 % rms InAs: InAs MBE and 2.0 MOVPE growth SAM structure Slide 22

23 Earth Explorer 8 Opportunity Mission Release of the Call Proposals M industrial cost for the space segment and mission specific ground segment a minimum TRL of 4-5 required by the end of Phase A 31 proposals received 7 proposals based on lidar technique Results of evaluation expected in NOV 2010 Slide 23

24 The ESA Living Planet Programme EXPLORER 1 CryoSat CryoSat-2 EXPLORER 2 GOCE EXPLORER 3 SMOS EXPLORER 4 ADM-Aeolus EXPLORER 5 SWARM EXPLORER 6 EXPLORER 7 EXPLORER 8 Call release Proposals Phase 0 Selection for phase A: PREMIER, CoReH2O, BIOMASS Call release Selection for phase A Proposals EarthCARE Slide 24

25 Thank you for your attention Merci de votre attention Bedankt voor jullie andacht Danke für Ihre Aufmerksamkei Gracias por su atención Grazie per la vostra attenzione σας ευχαριστώ! Slide 25