FY-4A Introduction

FY-4 is the 2nd generation FengYun Geostationary meteorological satellite. The spacecraft has the following parameters:

Fig. FY-4A spacecraft.

Tab. FY-4 Spacecraft parameters.

Mission objectives of CMA FengYun Geo. satellites are:

Fig. Recent and future CMA FengYun Geo. missions.

Compared with FY-2:

	FY-4A	FY-2F/G
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
Main payloads	AGRI	VISSR
	Band range: 0.45~13.8μm	Band range: 0.55~12.5μm
	Spatial resolution: 0.5~4km	Spatial resolution: 1.25~5km
	Full disk time: 15 min	Full disk time: 30 min
	Observation area: flexible	Observation area: fixed
	GIIRS	N/A
	Band range: 700~1130cm^-1, 1650~2250cm^-1
	Spectrum resolution: 0.8cm^-1, 1.6cm^-1
	Spatial resolution: 16km
	LMI	N/A
	Band: 777.4±0.5nm
	Size: 2×300mm×400mm
	Spatial resolution: 7.8km
	Coverage: China and surrounding
	SEP	SEM
	Particles, magnetic field	Particles

Compared with similar satellite worldwide:

		FY-4 (China)	GOES-R (USA)	Himawari-8 (Japan)
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)	N/A	N/A
	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	N/A
Space		Particles/magnetic field/X-ray	Particles/magnetic field/Solar imaging	N/A