China's first satellite was successfully launched into orbit in April 1970, and China has since developed a dozen or so geosynchronous orbit communications satellites.
Four types of geo-synchronous orbit communications satellite have so far been developed, namely the successful DFH-2, DFH-2A, DFH-3 and DFH-4. DFH-2 and DFH-2A satellites are spin-stabilised, while DFH-3 and DFH-4 are 3-axis stabilised.
The DFH-4 satellite is a Chinese third-generation communications satellite characterised by its high power, heavy payload capacity and extended service life. With a design life span of 15 years, it can accommodate various C, Ka, Ku and S band transponders for communications, broadcast and DTH satellite services.
The technical parameters for the DFH series of communications satellites are listed below:
|Satellite Lift-off Mass (kg)||920||1044||2320||5200|
|Power (kw)||——||——||1.7||10.5 (EOL)|
|In-Orbit Life Span (years)||3||>4||>8||15|
|Number of Transponders||2||4||24||54|
|Stabilisation Mode||Spin stabilised||Spin stabilised||3-axis||3-axis|
As of May 15, 2009, China Great Wall Industry Corporation (CGWIC) has signed four contracts for DFH-4 satellite in-orbit delivery. The signature in December 2004 of the contract for the in-orbit delivery of the NigComSat-1 satellite marked a major milestone for the emergence of Chinese satellites on the world commercial satellite market. The NigComSat-1 satellite was delivered in July 2007, and VeneSat-1 was subsequently delivered to Venezuela in December 2008.
The third and fourth DFH-4 communications satellites are currently under development for our international clients.