China operated a constellation of three Dongfanghong DFH-2 (Dong Fang Hong - The East is Red) communications satellites in GEO for domestic needs. Designed, manufactured, and launched by indigenous means, the modest DFH-2 Dongfanghong DFH-2 (Dong Fang Hong - The East is Red) space craft were analogous to 1960's era Western GE0 satellites (e.g., INTELSAT 3), although slightly heavier.
After an initial CZ-3 launch failure in January, 1984, the first Chinese GEO satellites were deployed in April, 1984, and February, 1986, to 125 degrees E and 103 degrees E, respectively. Both satellites apparently continued to operate until 1990-1991, by which time they had been replaced by the operational DFH-2 series.
With an on-orbit mass of 441 kg (compared to 433 kg for the earlier satellites), DFH-2 spacecraft were successfully placed in GEO in March, 1988, December, 1988, and February, 1990, and positioned at 87.5 degrees E, 110.5 degrees E, and 98 degrees E, respectively. All three satellites remained on station at the end of 1994. A fourth DFH-2 was lost on 28 December 1991 when its CZ-3 upper stage failed to reignite.
The body of the DFH-2 was a cylinder with 2.1m in diameter and 1.6m in height. The 920kg satellite has a designed life of 3 years and adopted double spin-stablized attitude control system. It had 2 C-band transponders with 8W output power of each one. The conic horn communications antenna of the first DFH-2 was installed on despin component and had 14?angle coverage. It could provide services not only to ground stations in China, but also to offshore mobile stations. Small communications capacity resulted from low EIRP and specific value of antenna gain and system noise temperature (G/T) affected the economic benefit of the satellite. The second DFH-2 satellite used domestic beam parabolic antenna with 5 ??elliptic beam, whose antenna gain was increased by 6-9dB from that of the first satellite. The communications capacity had increased sharply and the requirements for the power of ground station was reduced.
DFH-2A-1, 2A-2, 2A-3 were later renamed ChinaSat-1, ChinaSat-2 and ChinaSat-3, respectively. China began to develop the DFH-2A communications satellite while launching and using the DFH-2. The DFH-2A was the upgraded DFH-2 with function improved greatly and had 4 transponders. The output power of each power amplifier was10W. The EIRP within the service area was greater than 32dBW and G/T value greater than -11dB/K. The DFH-2A had liftoff mass of 1040kg and designed lifetime of 4 years. 3 DFH-2A satellites were launched into orbit on March 7, 1988, Dec. 22, 1988 and Feb. 4, 1990 respectively and positioned at 87.5?E, 98?E and 115?E. All the 3 satellites had worked for more than 5 years.
The DFH-2 was a spin-stabilized, drum-shaped satellite with a diameter of 2.1 m and a height of 3.1 m. The communications payload consisted of only two 6/4 GHz transponders with an output power of 10 W. The total electrical power capacity was assessed to be about 300 W (the first two experimental satellites were rated at 284 W) (References 223-227).
Prior to 1993 all DFH satellites were operated by the military. All DFH-2As had exhausted fuel and halted operation by the early 1990s.
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