The Sanya Institute of Remote Sensing said it would launch three optical satellites next year.
It will add another three optical satellites, two hyperspectral satellites and two Synthetic Aperture Radar satellites to complete the Satellite Constellation Programme by 2021, for conducting round-the-clock remote-sensing over the tropical sea area, state-run Xinhua news agency reported.
Yang Tianliang, director of the institute, said the network was calculated to broadly cover the area between 30 degrees north and south of the equator.Yang said the programme would provide scientific support for China's initiative of the 21st Century Maritime Silk Road and emergency response efforts at sea.
China claims sovereignty on almost of the South China Sea. The Philippines, Vietnam, Malaysia, Bureni and Taiwan have counter claims.
China has already firmed up its hold over the area by building military installations in the reclaimed islands.
Meanwhile, reacting to a report by a US think tank which released satellite images showing deployment of radar and other high tech equipment for military use in the islands and reefs of the South China Sea, Foreign Ministry spokesman Lu Kang told media here that it was "normal" for China to build installations in an area over which it has sovereignty.
"If China is conducting any construction, peaceful activities or deploying defence facilities it is normal because it within our sovereignty," Lu told the media.
"Some individuals are making a fuss about this to hype it up. This clearly points to some ulterior motives," he said, adding that the situation in the South China Sea is becoming normal.
With the concerted efforts of China and regional countries, the situation has steadily stabilised and the countries outside the region should respect efforts and "stop hyping up relevant issue", he said.
China is involved in maritime disputes in the South and East China Seas. It claims almost all of the South China Sea and has also laid claims on the Senkaku islands under the control of Japan in the East China Sea, believed to harbor vast natural resources below their seabed.
The US has been periodically deploying its naval ships and fighter planes in the South China Sea to assert freedom of navigation in the disputed areas.