An infrared hyper-spectral vertical sounder, also the first space-borne
interferometer that flies in geostationary orbit to take measurements of
three dimensional atmospheric structure from interference of split light beams.
Technically featured by a 32×4 sensor array plane, a Michelson interferometer
working over different infrared bands for large-area, continuous, fast, and
accurate vertical air soundings of temperature and humidity.
GIIRS on FY-4B has spatial resolution of 12km, with better sensitivity and
calibration accuracy through improved structure and designs.
Fig. GIIRS of FY-4.
Primary instrument details:
|
FY-4B (Operational) |
FY-4A (R&D) |
Working bands |
LWIR: 680~1130 cm-1 |
LWIR: 700~1130 cm-1 |
MWIR: 1650~2250 cm-1 |
MWIR: 1650~2250 cm-1 |
VIS: 0.55~0.90μm |
VIS: 0.55~0.90μm |
Spectral resolution |
0.8 cm-1 |
LWIR: 0.8 cm-1, MWIR: 1.6 cm-1 |
Spatial resolution |
IR: 12km SSP VIS: 1km SSP |
IR: 16km SSP VIS: 2km SSP |
Temporal resolution |
45min |
1hour |
Regional observation at 1 hour intervals.
Parameters of FY-4B GIIRS.
Band |
Range (cm-1) |
Sensitivity (mW/m2sr cm-2) |
Calibration accuracy (K) |
1 |
700 ~ 1130 |
0.5 |
0.7K |
2 |
1650 ~ 2250 |
0.1 |
0.7K |
VIS band
○ SNR: S/N≥200(ρ=100%)
○ Calibration accuracy: better than 10ppm