FY-4 Series


FY-4 series is China's second generation geostationary meteorological satellites. The satellite attitude is three-axis stabilized to improve the time resolution of observations and regional mobility. The new generation satellites are designed with an enhanced imagery scanning capability, desirable for monitoring small and medium scale weather systems. It is enabled with vertical atmospheric sounding and microwave detection capabilities to address 3D remote sensing at high altitudes. It is also enabled with solar observations for extreme ultraviolet and X-rays, in a bid to enhance China's space weather watch and warning capability. FY-4 will be made either carrying optical or microwave instruments. An optical satellite will carry onboard a 10-channel 2D scanning imager, an interferometric vertical detector, a lightning imager, CCD camera and an earth radiation budget instrument. The satellite produces earth disc imageries every 15 minutes..

Compared with FY-2:

Platform stabilization Three-axis stabilization Spin stabilization
Working life in orbit 7 years as designed 3 years as designed
Observation efficiency >85% appr. 5%
Observation mode Imaging, sounding and lightning Imaging


Observing instruments aboard FY-4:

  • Advanced Geosynchronous Radiation Imager (AGRI). The instrument has 14 channels with a spectral range set between 0.55μm and 13.8μm.
  • Geo. Interferometric Infrared Sounder (GIIRS).
  • Lightning Mapping Imager (LMI).
  • Space Environment Package (SEP).
  • Solar X-EUV imaging telescope (SXEUV).

Compared with similar satellite worldwide:

Imaging Spatial resolution VIS/NIR: 0.5~1km
IR: 2~4km
VIS/NIR: 0.5~1km
IR: 2km
VIS/NIR: 0.5~1km
IR: 2km
Time resolution 15min 5min 10min
No. bands 14 16 16
Accuracy 0.1K 0.1K 0.1K
Sounding Spectrum range LWIR: 700~1130cm-1 (8.85~14.29μm)
MWIR: 1650~2250cm-1 (4.44~6.06μm)
No. Bands 1650
Spectrum resolution 0.625cm-1
Spatial resolution 16km
Lightning Central wavelength: 777.4nm
Time resolution: 2ms
Central wavelength: 777.4nm
Time resolution: 2ms
Space Particles/magnetic field/X-ray Particles/magnetic field/Solar imaging N/A


FY-1 FY-4A