The FY-1C Meteorological Satellite and Its Remote Sensor
Gong Huixing, Zheng Qinbo, Weng Chuijun
Shanghai Institute of Technical Physics,
Chinese Academy of Sciences, Shanghai, China (200083)
Introduction
China successfully launched the FY-1C Meteorological Satellite from Taiyuan Satellite Launch
Center by the CZ-4B carrier rocket at 09:33 (Beijing time) on May 10th, 1999. The satellite is placed
in a sun-synchronous orbit at an altitude of 862.8 km with an inclination of 98.8°, an eccentricity of
0.009, at descending local time of 08:34 and with a period of 102.23 min.
China once launched two sun-synchronous orbit meteorological satellites FY-1A and FY-1B in
1988 and 1990 respectively. Because the satellite attitude was out of control, neither satellite had
achieved its predetermined lifetime. In order to enhance the earth observation ability of satellite and
establish China's own operational system of meteorological satellite, China decided to continue
developing the sun-synchronous orbit meteorological satellite. Compared to FY-1A and FY-1B, FY-1C
has made the following improvements:
- Improve the reliability of satellite, and the designed lifetime is increased from one year to two
years;
- The record capacity for image data onboard is increased from 60 min to 300 min, so as to
acquire the global image data;
- The number of detecting bands of visible and infrared scanning radiometer is increased from 5
to 10.
The main missions of FY-1C satellite includes:
-
Continuously observe the global atmosphere and surface scenes with the 10-band scanning
radiometer;
- Conduct remoter sensing experiments of ocean color;
- Utilize the satellite ground stations in China to receive the image data played back from
satellite, and acquire the global cloud images with a ground resolution of 3.1 km and the
ocean surface temperature images or 10 band images of any region on the earth with a ground
resolution of 1.1 km once a day.
FY-1C Satellite
Fig.1 shows the FY-1C satellite with a dimension of 2.02×2.00×10.5m and a weight of 954
Kg. There are four solar cell plates with a total area of 9.58m2 on both sides of the satellite. They
provide the satellite with an average power consumption of about 250 W. The satellite attitude is
three-axis stabilized and the deviation is less than 0.4° . On its side facing the ground, two 10-channel
scanning radiometers which are redundant each other are mounted. The image signals are processed
onboard in real time, resulting in 10 channel digital signals with a ground resolution of 1.1 km and
data rate of 1.3308 Mbps to be transmitted to the ground by a HRPT transmitter at a transmission
frequency of 1700.4 MHz, and 4 channel digital image signals which have undergone scanning
geometric distortion correction with a ground resolution of 3.1 km and data rate of 88.72 kbps to be
recorded on the onboard solid-state storage. When the satellite enters the receiving range of the
ground stations in China, the stored data are played back at a data rate of 1.3308 Mbps and a record-play
ratio of 1:15.
Because the number of detecting channels of the scanning radiometer on FY-1C is 4 more than
that of the AVHRR on NOAA satellite and the channel number for transmission in real time on FY-1C
is doubled. Therefore, the ground stations for NOAA satellite must be improved so as to be able
to receive the real-time image data transmitted from the FY-1C satellite.
Fig.1 FY-1C satellite.
