1 / 26

CHRIS (Compact High Resolution Imaging Spectrometer)

CHRIS (Compact High Resolution Imaging Spectrometer). Dr Mike Cutter EO & Technology Business Manager. sira electro-optics. sira group. CHRIS/PROBA – low cost mission. CHRIS Design concept - programmable hyperspectral Spectral range - VNIR Spatial sampling - 17 m @ perigee

nola
Télécharger la présentation

CHRIS (Compact High Resolution Imaging Spectrometer)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CHRIS (Compact High Resolution Imaging Spectrometer) Dr Mike Cutter EO & Technology Business Manager siraelectro-optics siragroup

  2. CHRIS/PROBA – low cost mission • CHRIS • Design concept - programmable hyperspectral • Spectral range - VNIR • Spatial sampling - 17 m @ perigee • PROBA Platform • Small satellite (100kg) – launched October 2001 • Agile 3-axis stabilised platform - roll, pitch & yaw • Provides multi-angle observations & motion compensation • Mission Objectives • Obtain selected land and littoral images • Obtain multi-view angle measurements (aerosols, BRDF) • Evaluate in-orbit performance - precursor mission

  3. Scene Radiance Information The radiance field is at least 7 dimensional  ( v, s ,, , x, y, t ) Spectral Information Temporal Information Angular (BRDF) Spatial Information

  4. MVA Data from CHRIS/PROBA • PROBA: • Along-track: five angles per overpass: 0°, ±36°, ±55° @ ground MVA = Multi-View Angle

  5. MVA data from CHRIS/PROBA Day n+y Day n Day n+x By rolling the satellite ± 25º in the across-track direction it is possible to image a fixed point on the Earth surface at different sensor view angles. MVA = Multi-View Angle

  6. Information from MVA Image Left: Nadir-view, multispectral composite (0.5µm, 0.65 µm and 0.85 µm) showing wheat (red), bare soil (blue) and oil seed rape (white). Right: Multi-angle composites (nadir + two oblique angles) at recorded 0.5 µm, 0.65 µm and 0.85 µm, respectively.

  7. Instrument Design

  8. CHRIS

  9. Specification • Image area 13 km square @ perigee • Spatial sampling interval 17 m @ perigee • Spectral range (nominal) 415nm to 1050nm • Spectral resolution 1.25 to 11nm • Spectral/Spatial registration +/- 0.05 pixel • Gain stage 4 levels (albedo 0.5,1,2,4 levels) • Digitisation 12 bits • Signal-to-noise ratio 200 (@ 0.2 albedo, 17m, 10nm) • Data per (13x13 km2) image 16.4Mbytes • Mass/power < 14 kg/ 10 W primary power • Volume 790 x 260 x 200 mm3

  10. GSD/band number options

  11. Platform Aspects

  12. Platform Aspects • Platform - ESA PROBA (Verhaert, Belgium) • Orbit 570- 730 km, sun-synch. (10.30am node) • Inclination 97.97º, • Repeat period 11 days • Dimensions 800mm x 600mm x 600mm • Power/mass < 100 W/100 kg • Pointing • Along-track 0 º, +/- 36º, +/-55º (@ ground) • Across-track +/-25º (@ ground) • Absolute pitch/roll/yaw < +/- 0.1º • Control of pitch/roll/yaw < +/- 0.015º/s (11% of imaging pitch rate) • Maximum pitch rate 0.7º/s • Down-link S-band: 1 Mbit/s (5 images/day) • Ground Station Redu, Belgium

  13. Observation Plan

  14. Observation Programme • Programme defined by CHRIS Steering Group (UK, ESA) • AO issued by ESA in 2000 for first year mission. • Observations • 21 Core sites, 31 additional sites, 12 reserve sites • Approx. 60 PIs world wide • Observation modes (5 off) excluding calibration • Mode 1: Low resolution – aerosols, 62 bands • Mode 2: High resolution – water, 18 bands • Mode 3: High resolution – land, 18 bands • Mode 4: High resolution – chlorophyll, 18 bands • Mode 5: Half swath/high resolution – land, 37 bands • Observation logistics • Apply 48 hour cloud predictions to aid target selection • Details: WWW.PROBA-CHRIS.ORG.UK

  15. Location of CHRIS Test Sites

  16. Sample Images

  17. Antwerpen

  18. Satellite Pitch Rates Spectral

  19. New York

  20. Current Status • Platform Commissioning • Platform undergoing fine tuning wrt pointing • Platform processor intermittent issue being investigated • Reviewing options for improving operational approach • Instrument Commissioning • Instrument performance assessment on-going • Data processing being validated for each imaging mode • Wavelength calibration (O2 line) results being evaluated • Downlink • Platform commanding approach being refined. • Reviewing options for utilising a Kiruna (polar) downlink. • Data sets • Plan to issue sample data sets to PIs in August 2002

  21. Acknowledgements • BNSC for partial funding of CHRIS • ESA for the launch opportunity, support for calibration activities, data processing, the planning tool and website. • Redu, ESOC (Belgium) for operational support • Verhaert (Belgium) for platform support • RSAC (UK) for preparation of the planning tool & jointly with ESSC the CHRIS website. • UK PIs: • Prof. Mike Barnsley (BRDF), Swansea University • Dr Jeff Settle (Aerosols), ESSC, Reading University • Dr Samantha Lavender (Coastal), Plymouth University

  22. The End WWW.PROBA-CHRIS.ORG.UK

More Related