1. Example of sensitivity analysis Sophie Lachérade, Bertrand Fougnie
CNES
Ouahid Aznay
CS-SI
Lunar WS – 3rd December 2014, Darmstadt

2. Sensitivity tree Data source, Measurement technique Non-linearity
Source of degradation:
Out of band rejection
On-orbit degradation
Non-linearity
Spectral response
Dark signal correction
Oversampling
Integration step
Absolute calibration
Data source
Sensitivity study parameters
ΔSRF ΔI
Δ(x,y,z)
SRF
Sensor Irradiances
Satellite position
GIRO inputs
GIRO

3. Sensitivity tree Data source, Measurement technique Non-linearity
Source of degradation:
Out of band rejection
On-orbit degradation
Non-linearity
Spectral response
Dark signal correction
Oversampling
Integration step
Absolute calibration
Data source
Sensitivity study parameters
ΔSRF ΔI
Δ(x,y,z)
SRF
Sensor Irradiances
Satellite position
GIRO inputs
GIRO

4. Summary
Oversampling
Dark Signal
ROLO inputs

5. Oversampling Inputs of the oversampling study: Questions:
2012_02_14_17_58_56_B2
2012_02_14_17_58_56_B2
+ 90°
2012_02_14_18_49_30_B2
Questions:
- What is the impact of a resampling error on the integrated irradiances ?
- Is it the same impact whatever the orientation of the Moon in the image ?

6. Oversampling Oversampling errors introduced in the image:
Resampling grids used to simulate an resampling error in the lunar processings

7. Oversampling
Reference
image

8. Oversampling

9. Dark signal correction

10. Dark signal correction
1% of IPHR
when g=90°
0.1% of IPHR
when g=3°
IPHR= IPHR+5x10-6 (w/m²/sr/µm)

11. Dark signal correction
2.5% of IPHR
when g=90°
0.2% of IPHR
when g=3°
IPHR= IPHR+1x10-5 (w/m²/sr/µm)

12. Dark signal correction
5% of IPHR
when g=90°
0.4% of IPHR
when g=3°
IPHR= IPHR+2x10-5 (w/m²/sr/µm)

13. ROLO inputs
ROLO
→ Impact of a bias (±1°) in the librations components:
- satellite latitude
- satellite longitude
- sun longitude
→ Impact of a bias (±1°) in the lunar phase angle

14. Satellite position
Impact of a bias in the satellite latitude

15. Satellite position
Impact of a bias in the satellite longitude

16. Satellite position
Impact of a bias in the sun longitude

17. ROLO inputs
Impact of a bias in the lunar phase angle

18. Conclusions: just an example !
Data source, Measurement technique
Source of degradation:
Out of band rejection
On-orbit degradation
Non-linearity
Spectral response
Dark signal correction
Oversampling
Integration step
Absolute calibration
Data source
Sensitivity study parameters
ΔSRF ΔI
Δ(x,y,z)
SRF
Sensor Irradiances
Satellite position
GIRO inputs
GIRO

19. Conclusions Lunar sensitivity analysis very useful to
Better understanding the lunar calibration processing chain
Determining the more sensitive component of the chain
- depending of the system
- depending of the observed lunar phase angle
Associating uncertainties to each step of the processing chain