Minimize MIPAS Cal/Val
Minimize Calibration Activities

The definition and frequency of instrument in-flight calibrations needed during the MIPAS lifetime were defined by a Calibration team before launch and revised during the instrument Commissioning Phase.

Because of the Interferometer Drive Unit anomaly in 2004 (see Mission Operations Overview) , the in-flight calibration strategy had been adapted to the new mission. The main changes affected the spectral resolution, the number of sweeps per scan and therefore the duration of calibrations themselves."

Minimize Instrument Settings Changes

Beside configuration changes applied to the instrument in response to the major Interferometer Drive Unit anomaly, few other instrument settings have been modified during the MIPAS lifetime. A summary of those changes is reported in the present section.

Minimize In-Flight Calibrations during Full Resolution (FR) mission
Calibration Description Frequency
Offset

Offset calibration

450 seconds
ILS

Instrument Line Shape

1 orbit
WCC

Wear Control Cycle

5 orbits
RGC (IF8)

Radiometric Gain Calibration (1 scan of 300 Black Body + 300 Deep Space sweeps)

1 day
LOS

Line Of Sight measurements

1 week
IF16

Several limb scanning sequences in raw mode

2 months
IF9

Offset tangent height determination

3 months
IF11

Absence of high resolution features verification

3 months
PD-IF16-IF4-IF16

Passive Decontamination, followed by the calibration sequence IF16 – IF4 – IF16

6 months
IF4

Generation of the non-linearity coefficients

6 months
IF10

NESR0 verification

6 months
IF6

CBB and DS SNR characterization

1 year
IF14

Field of View In-Flight Check

1 year

 

Minimize In-Flight Calibrations during Optimized Resolution (OR) mission
Calibration Description Frequency
Offset

Offset calibration

800 seconds
ILS

Instrument Line Shape

1 orbit
WCC

Wear Control Cycle

automatically commanded by ESOC after each instrument transition to Heater

RGC (IF8)

Radiometric Gain Calibration (1 scan of 200 Black Body + 200 Deep Space sweeps)

1 day
LOS

Line Of Sight measurements

10 days
PD-IF16-IF4-IF16 Passive Decontamination, followed by the calibration sequence IF16 – IF4 – IF16 6 months