1. Calibration and Validation of Microwave Humidity Sounder onboard FY-3D Satellite
Yang Guo, Songyan Gu
NSMC/CMA Mar. 2018

2. outline FY3D MWHS Introduction Calibration process
On-orbit instrument performance
Inter-satellite Validation
Summary

3. MWHS Introduction
number of channel up to 15from 5, frequency points from 2 to 4.
Old Chs.
New Chs.
FY-3A/B/ MWHS
FY-3C/D MWHTS
Channel
Frequency（GHz） 1
89.0 2
118.750.08 3
118.750.2 4
118.750.3 5
118.750.8 6
118.751.1 7
118.752.5 8
118.753.0 9
118.755.0
150(V) 10
150.0
150(H)
183.31±1 11 12
183.31±1.8
183.31±3 13 14
183.31±4.5
183.31±7 15

4. Atmospheric Transmission at Microwave Wavelengths
118GHz
89GHz
183GHz
150GHz

5. MWHS Introduction MWHS instrument MWHS scan sequence
0º(Nadir)
90º
180±2º
Hot Targets
270º
53.35º
287±2º
Cold Space
306.65º
earth scene
accelerate
MWHS instrument
MWHS scan sequence
nonlinearity
Radiometer transfer function

6. Calibration process Calibration flow chart Quality control flow chart
No lunar intrusion
If a lunar intrusion

7. Band correction: Planck’s Law: Calibration flow chart
Triangular function
No lunar intrusion
If a lunar intrusion n
The variation of Nedt with number of N included in the average of the
Space view and internal target counts.
Band correction:
Planck’s Law:

8. Data_QA_Scan_Flag: ABCDE A_Flag: 0—preprocess success!
Calibration flow chart
Data_QA_Scan_Flag: ABCDE
A_Flag: —preprocess success!
1—preprocess Failure!
QC_Flag: —all channels cal success!
1—Part of the channel cal success!
2—all channels cal Failure!
moonAffect: 0—no lunar contamination!
1—lunar contamination!
Geoqc: ,01,02—Geolocation success!
11,12,13—Geolocation Failure!
No lunar intrusion
If a lunar intrusion
Use
to compute
Then use
to compute antenna
brightness temperature.
Compute scene TBs by antenna correction

9. FY-3D MWHSII Global Brightness Temperature（Ascending）

10. FY-3D MWHSII Global Brightness Temperature（Descending）

11. Instrument temperature and Warm Target temperature
Long-term trends of the internal warm target PRTs averaged temperatures and the instrument temperature

12. MWHS Warm Target View Count
AGC adjustment
AGC adjustment
Long-term trends of Warm Target view counts

13. MWHS Noise Equivalent Delta Temperature

14. Center Frequency（GHz）
Inter-satellite Validation of Observation
FY-3D MWHS VS. Soumi/NPP ATMS
Corresponding channels between
FY-3D MWHS and Soumi/NPP ATMS
Data :
Key match-up conditions
Difference of observing times < 20 minutes
Difference of satellite zenith angles < 5°
Distance < 3 km
Uniformity check : STD (3×3 pixels BT) < 1 K
Center Frequency（GHz）
MWHS Channel
ATMS Channel
89.0/88.2 1 --
118.750.08 2
118.750.2 3
118.750.3 4
118.750.8 5
118.751.1 6
118.752.5 7
118.753.0 8
118.755.0 9
150.0/165.5 10
183.31±1 11 22
183.31±1.8 12 21
183.31±3 13 20
183.31±4.5 14 19
183.31±7 15 18

15. Inter-satellite Validation of Observation
Ch.11
Ch.12
Ch.13
Ch.14
Ch.15
Brightness Temperature of MWHS versus that of ATMS

16. SUMMARY
FY-3D MWHS(II) on-orbit calibration system has been working well, and the basic calibration data are stable.
The Noise Equivalent Delta Temperature of FY-3D MWHS(II) is well characterized and meets the specification.
Assessments of FY-3D MWHS(II) performance will using NWP O-B and site calibration test data.

17. Thank you!