China has significantly expanded its electronic warfare (EW) and surveillance network across its artificial islands in the Spratly chain, with new assessments indicating a rapid build-out that is reshaping the South China Sea into what analysts describe as an increasingly contested “electronic battlespace.”
The findings were highlighted this month by the Asia Maritime Transparency Initiative (AMTI). According to AMTI, Beijing undertook major upgrades between 2023 and 2025 on Fiery Cross, Mischief, and Subi Reefs, installing new antenna fields and deploying mobile EW vehicles capable of monitoring, jamming, and targeting foreign military activity. Satellite imagery cited in the report shows at least six new paved antenna sites, mobile jamming platforms, and expanded intelligence, surveillance and reconnaissance infrastructure across the outposts.
Subi Reef now includes a roofed shelter constructed in 2025 for vehicle-mounted EW units, while Mischief Reef hosts five EW vehicles linked directly to fixed antenna arrays. AMTI also identifies new radomes at Subi and a circular launch-pad-type structure at Mischief designed for rapid antenna deployment. Reinforced coastal positions at Mischief suggest preparations for artillery or mobile weapons systems.
The developments align with broader trends outlined by the US-China Economic and Security Review Commission (USCC). In its November 2025 report, the commission states that the People’s Liberation Army has improved its ability to disrupt or paralyze U.S. military communications, reconnaissance links, and targeting systems—capabilities it describes as striking at the “nervous system” of modern U.S. operations. The USCC concludes that EW assets now sit at the core of China’s counter-intervention strategy aimed at constraining U.S. forces in the South China Sea and Taiwan Strait.
Earlier work by J. Michael Dahm in a 2020 Johns Hopkins Applied Physics Laboratory report anticipated the trend, describing how China’s Spratly outposts could act as regional EW hubs. Dahm detailed mobile jammers, direction-finding arrays, and ELINT facilities at Fiery Cross, Mischief, and Subi, enabling the triangulation and tracking of foreign forces and the degradation of their sensors.
Further reporting by the South China Morning Post adds context to China’s evolving doctrine. In December 2024, the newspaper noted that Chinese EW strategy prioritizes blinding U.S. carrier strike groups by targeting Aegis radars, E-2C Hawkeye coordination networks, and the Cooperative Engagement Capability. In July 2024, it reported that the Type 055 cruiser Nanchang employed AI-enabled radars to withstand jamming by U.S. EA-18G Growlers.
Questions about the operational impact of these systems surfaced in October 2025, when Real Clear Defense analyst Paul Crespo suggested that two U.S. aircraft lost near the USS Nimitz might have been affected by Chinese EW interference, though no official confirmation has been issued.
A 2020 China Maritime Studies Institute report by Chi Guocang argues that China’s fortified Spratly network also supports a secure submarine “bastion” for its nuclear-armed ballistic-missile submarines. Meanwhile, U.S. Lieutenant General John Caine told the Senate Armed Services Committee in April 2025 that the United States has “lost some muscle memory” in EW, warning that training and simulation capabilities have not kept pace with the threat environment.
(Inputs from Agencies/Wires)
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