China started to develop its geostationary meteorological satellites and associated ground application systems from the 1980s. China's first geostationary meteorological satellites were named FengYun-2, or FY-2 satellites. China launched its first geostationary meteorological satellite FY-2A on June 10, 1997, boarding a Long March III carrying rocket from the Xichang Satellite Launch Center. Positioned at 105oE above the equator on June 17, the satellite kicked off China's meteorological satellite era. Chinese geostationary meteorological satellites can be positioned at three points in space: 105oE, 86.5oE and 123oE. Of them, 105oE is retained for operational satellites, with two others for a backup or for a satellite that will soon be abandoned.
According to China's development plan for geostationary meteorological satellites, China's first generation geostationary meteorological satellites can be divided into three groups:
As of 2017, China has successfully launched 7 geostationary meteorological satellites. Of them FY-2A and FY-2B in the first group and FY-2C and FY-2D in the second group have ceased to work as drifted away from the geosynchronous orbit. The ones currently working in orbit are FY-2E in the second group, and FY-2F and FY-2G in the last group, which are going to be replaced by the new generation FY-4 series.
Observing instruments aboard FY-2:
On FY-2A/B, the same instrument has only three channels (0.5-1.05μm, 6.3-7.6μm and 10.5-12.5μm). On the rest of satellites (FY-2 C/D/E / F/G/H), the infrared long window area (10.5-12.5μm) was split into two channels, with an additional middle range infrared channel (3.5-4.0μm). As a result, the instrument's spatial resolution is raised from 5.76 km (IR) and 1.44 km (VIS) to 5.0 km (IR) and 1.25 km (VIS). The disc image scanning is set at 30 minutes per cycle.
FY-2 satellites are equipped with a particle detector and an X-ray detector to monitor the space environment where the satellites are working. They collect space environment data, including solar activities, and send them back to the ground application system for satellite projects planning, space environment studies, and space hazards warning.
|Service||Dir||Frequency||Bandwidth||Polarisation||D/A||Datarate / Baseband||Comments|
|CDAS||S-E||1681.6 MHz||20000 kHz||linear||D||14000 kbps||Raw data|
|HRIT||S-E||1687.5 MHz||260 kHz||linear||D||660 kbps||High-resolution data|
|LRIT||S-E||1690.5 MHz||1000 kHz||linear||D||150 kbps||Selected data|
|DCP||E-S||401.1~401.4 MHz||3 kHz||RHCP||D||0.100 kbps||Regional DCP reports|
|E-S||402.0~402.1 MHz||1 kHz||RHCP||D||0.100 kbps||International DCP reports|