“An information technology-based war at sea is sudden, cruel and short…” was how the Chinese military characterized a peer-to-peer naval conflict at sea in a public statement at the beginning of the month during PLAN naval exercises. The exercises, occurring in the East China Sea, were designed to increase the PLAN’s “assault intensity, precision, stability and speed of troops amid heavy electromagnetic influences” or in other words, electronic warfare. China and the United States are preparing and force posturing to contest the electromagnetic spectrum in the South China Sea and further north in the East China Sea.

One of the defining characteristics of China’s actions in the South China Sea has been the construction of radar installations across the majority of its artificial features in the region.According to CSIS’s Asia Maritime Transparency Initiative, a variety of radar installations have been constructed on Cuarteron Reef, Fiery Cross Reef, Gaven Reef, Hughes Reef, Johnson Reef, Mischief Reef and Subi Reef. The purpose of these installations will vary and some will have dual uses—for instance a few of the radars on Fiery Cross and Subi Reef will be used to facilitate air operations from the runways housed on those features—but together, the facilities will significantly expand the real-time domain awareness and ISR capabilities of the PLA over a large portion of the South China Sea.
http://nationalinterest.org/blog/the-buzz/electronic-warfare-comes-the-south-china-sea-why-it-matters-17454