Description
The MicroWave Humidity Sounder-II (MWHS-II) is an important instrument onboard FengYun-3C
(FY-3C), the first operational satellite in a series of the second generation of polar-orbiting
operational meteorological satellites of China.
The MWHS-II on FY-3C and future FY-3s is an improved version of early MWHS model that fly on
FY-3A/B. Additional eight channels in 118-GHz band and a 89-GHz channel are added to the MWHS-I.
MWHS-II was designed for observing the distribution of global atmospheric thermodynamics
information, and monitoring the severe convective systems such as typhoon and rainstorm in
all-weather conditions. Assimilation of MWHS-II will improve the analysis of atmospheric humidity
and temperature fields required for numerical weather prediction (NWP).
MWHS-II is a total power microwave radiometer, which has fifteen channels in the range 89-191GHz.
Five sounding channels have center frequency at 183.31GHz water vapor absorption line, each having
two pass-bands. Eight sounding channels have center frequency at 118.75GHz oxygen absorption line.
One of the two window channels is at 89GHz, and the other one is at 150GHz on FY-3C/D or 166GHz on FY-3E.
In the normal working mode for MWHS-II on orbit, two offset-fed parabolic antennas are
perpendicular to flight track. MWHS-II performs cross-track scanning with a swath of 2700 km.
The incident microwave radiation is fed to corrugated feed horn via reflectors, then the beam is
split by a quasi-optical system into required frequency bands for 118 and 183GHz to obtain the
observation expressed in the form of counts. Each receiver is operated in double sideband mode
to improve the sensitivity.
| Satellite |
FY-3C ,
FY-3D ,
FY-3E
|
| No. Channels |
15 |
| Spatial Resolution |
16km (183GHz) / 32km (other) |
Characteristics
| Channel |
Central frequency (GHz) |
Polarisations |
Bandwidth (MHz) |
Dynamic range (K) |
NEΔT (K) |
Calibration Bias (K) |
3dB band width |
| 1 |
89.0 |
QH |
1500 |
3~340 |
1.0 |
1.3 |
2.0° |
| 2 |
118.75±0.08 |
QV |
20 |
3~340 |
3.6 |
2.0 |
2.0° |
| 3 |
118.75±0.2 |
QV |
100 |
3~340 |
2.0 |
2.0 |
2.0° |
| 4 |
118.75±0.3 |
QV |
165 |
3~340 |
1.6 |
2.0 |
2.0° |
| 5 |
118.75±0.8 |
QV |
200 |
3~340 |
1.6 |
2.0 |
2.0° |
| 6 |
118.75±1.1 |
QV |
200 |
3~340 |
1.6 |
2.0 |
2.0° |
| 7 |
118.75±2.5 |
QV |
200 |
3~340 |
1.6 |
2.0 |
2.0° |
| 8 |
118.75±3.0 |
QV |
1000 |
3~340 |
1.0 |
2.0 |
2.0° |
| 9 |
118.75±5.0 |
QV |
2000 |
3~340 |
1.0 |
2.0 |
2.0° |
| 10 |
150.0 |
QH |
1500 |
3~340 |
1.0 |
1.3 |
1.1° |
| 11 |
183.31±1 |
QV |
500 |
3~340 |
1.0 |
1.3 |
1.1° |
| 12 |
183.31±1.8 |
QV |
700 |
3~340 |
1.0 |
1.3 |
1.1° |
| 13 |
183.31±3 |
QV |
1000 |
3~340 |
1.0 |
1.3 |
1.1° |
| 14 |
183.31±4.5 |
QV |
2000 |
3~340 |
1.0 |
1.3 |
1.1° |
| 15 |
183.31±7 |
QV |
2000 |
3~340 |
1.0 |
1.3 |
1.1° |
| Channel |
Central frequency (GHz) |
Polarisations |
Bandwidth (MHz) |
Dynamic range (K) |
NEΔT (K) |
Calibration Bias (K) |
3dB band width |
| 1 |
89.0 |
QH |
1500 |
3~340 |
1.0 |
1.3 |
2.0° |
| 2 |
118.75±0.08 |
QV |
20 |
3~340 |
3.6 |
2.0 |
2.0° |
| 3 |
118.75±0.2 |
QV |
100 |
3~340 |
2.0 |
2.0 |
2.0° |
| 4 |
118.75±0.3 |
QV |
165 |
3~340 |
1.6 |
2.0 |
2.0° |
| 5 |
118.75±0.8 |
QV |
200 |
3~340 |
1.6 |
2.0 |
2.0° |
| 6 |
118.75±1.1 |
QV |
200 |
3~340 |
1.6 |
2.0 |
2.0° |
| 7 |
118.75±2.5 |
QV |
200 |
3~340 |
1.6 |
2.0 |
2.0° |
| 8 |
118.75±3.0 |
QV |
1000 |
3~340 |
1.0 |
2.0 |
2.0° |
| 9 |
118.75±5.0 |
QV |
2000 |
3~340 |
1.0 |
2.0 |
2.0° |
| 10 |
150.0 |
QH |
1500 |
3~340 |
1.0 |
1.3 |
1.1° |
| 11 |
183.31±1 |
QV |
500 |
3~340 |
1.0 |
1.3 |
1.1° |
| 12 |
183.31±1.8 |
QV |
700 |
3~340 |
1.0 |
1.3 |
1.1° |
| 13 |
183.31±3 |
QV |
1000 |
3~340 |
1.0 |
1.3 |
1.1° |
| 14 |
183.31±4.5 |
QV |
2000 |
3~340 |
1.0 |
1.3 |
1.1° |
| 15 |
183.31±7 |
QV |
2000 |
3~340 |
1.0 |
1.3 |
1.1° |
| Channel |
Central frequency (GHz) |
Polarisations |
Bandwidth (MHz) |
Dynamic range (K) |
NEΔT (K) |
Calibration Bias (K) |
3dB band width |
| 1 |
89.0 |
QH |
1500 |
3~340 |
0.4 |
1.0 |
2.0° |
| 2 |
118.75±0.08 |
QV |
20 |
3~340 |
2.2 |
2.4 |
2.0° |
| 3 |
118.75±0.2 |
QV |
100 |
3~340 |
1.0 |
1.2 |
2.0° |
| 4 |
118.75±0.3 |
QV |
165 |
3~340 |
0.8 |
1.2 |
2.0° |
| 5 |
118.75±0.8 |
QV |
200 |
3~340 |
0.8 |
1.2 |
2.0° |
| 6 |
118.75±1.1 |
QV |
200 |
3~340 |
0.8 |
1.0 |
2.0° |
| 7 |
118.75±2.5 |
QV |
200 |
3~340 |
0.8 |
1.0 |
2.0° |
| 8 |
118.75±3.0 |
QV |
1000 |
3~340 |
0.5 |
1.0 |
2.0° |
| 9 |
118.75±5.0 |
QV |
2000 |
3~340 |
0.5 |
1.0 |
2.0° |
| 10 |
166.0 |
QH |
1500 |
3~340 |
0.4 |
1.0 |
1.1° |
| 11 |
183.31±1 |
QV |
500 |
3~340 |
0.6 |
1.0 |
1.1° |
| 12 |
183.31±1.8 |
QV |
700 |
3~340 |
0.6 |
1.0 |
1.1° |
| 13 |
183.31±3 |
QV |
1000 |
3~340 |
0.5 |
1.0 |
1.1° |
| 14 |
183.31±4.5 |
QV |
2000 |
3~340 |
0.5 |
1.0 |
1.1° |
| 15 |
183.31±7 |
QV |
2000 |
3~340 |
0.5 |
1.0 |
1.1° |
Data and Products
Calibration and Validation
MWHS-II calibration and validation
FY-3E MWHS-II SRF (ZIP)
