As part of its ongoing aggressive efforts to illegally dominate the South China Sea (SCS), the Chinese Communist Party (CCP) is deploying a sophisticated network of sensors and surveillance platforms across the SCS. China claims the system is purely civilian and calls it the “Blue Ocean Information Network.”
More likely this network is military, or at least “dual-use,” and will be used to extend the People’s Liberation Army Navy‘s (PLAN) reach and capability throughout the region.
As H.I Sutton at Forbes notes:
While ostensibly civilian, these can be viewed as part of the Chinese Navy’s (PLAN) efforts to control the SCS. It is unrealistic to assume that their sensor data cannot be accessed by the PLAN for military purposes. And they may be part of a much larger sensor network, most of which is unseen beneath the waves. This reinforces China’s strategic advantage over other countries in the region, and can be used to monitor U.S. Navy movements.
“Many of these [platforms] are in Chinese waters,” Sutton reports, but others are “floating in international waters,” and some are on China’s illegal artificial island bases.
According to Forbes:
The platforms carry a range of sensors and communications. These include electro-optical / infrared sensor turrets, high frequency radio and cellular masts. Most also have a large radar dome on them, which may be the primary sensor. The platforms are unoccupied, and rarely need maintenance.
With these platforms China has greatly increased its radar coverage of the South China Sea. They now have an uninterrupted chain between Hainan and its bases in the Paracel and Spratly Islands. Many of these islands already have radar sites. And one unoccupied atoll, Bombay Reef, now has one of the platforms on its shoreline.
There is also an underwater component to this network, explains Sutton. It is sometimes referred to as the “Underwater Great Wall,” and is comparable to the U.S. Sound Surveillance System (SOSUS) used to track Soviet submarines during the Cold War. The Chinese system similarly includes sonar arrays on the ocean floor, but with far more modern and sophisticated technology.
Together these two systems (surface and subsurface) provide China an increasing ability to monitor and control major parts of the SCS. Specifically, the Center for Strategic and International Studies (CSIS) noted in its June 2020 report, that this vast maritime surveillance network gives China:
The ability to rapidly relocate platforms and sensors during a crisis may afford Chinese authorities information advantages in a crisis. This could include persistent monitoring of contested waters or a disputed island. An obvious military application might be to use the platforms and deployable underwater systems to close gaps in radar, sonar, or communications coverage in a military confrontation.
As CSIS concludes in its report, China’s Blue Ocean Information Network in the South China Sea “is the most visible and ambitious project of its kind, using information technology to advance China’s goal of becoming a great maritime power.”