Iran’s US radar strike exposes China’s South China Sea gap

Iran reportedly struck and destroyed the US AN/TPY-2 radar deployed in Jordan during its ongoing war with the United States and Israel.

What makes the AN/TPY-2 distinctive is that, despite operating in the X-band of the electromagnetic spectrum — which is generally suited for fire control (directing weapons to their target) — it can also perform long-range surveillance functions.

This capability is attributed to the radar’s large phased-array antenna, high transmit power and advanced beamforming techniques. As a result, the AN/TPY-2 is an expensive platform, costing just under half a billion dollars, and only 13 such systems have been manufactured.

The destruction of the AN/TPY-2 underscores the difficulty China faces in achieving information dominance in the South China Sea (SCS), despite massive investment in intelligence, surveillance and reconnaissance (ISR) capabilities there.

Although China has developed multi-layered, overlapping ISR coverage in the SCS, it has yet to establish a well-networked system-of-systems architecture — a gap that presents an opportunity for Southeast Asian claimant states, the United States and its allies to challenge China’s “informationized warfare” in any SCS conflict.

According to the CSIS Asia Maritime Transparency Initiative (AMTI), since 2022, China has built several new facilities to enhance its ISR and electronic warfare (EW) capabilities on its Spratly Island features.

These facilities include mobile ISR and EW systems and antenna arrays across all of China’s “big three” Spratly features, namely Fiery Cross, Subi and Mischief reefs. A pair of ISR radomes, each with a small antenna in front, was also built on Subi Reef; similar radomes have existed on Fiery Cross and Mischief Reef since 2017. These investments reflect China’s efforts to achieve information dominance in the SCS.

However, achieving information dominance is easier said than done. The geography of the SCS, combined with the physics underlying radar operation, constrains China’s ISR coverage.

Because the SCS features are built on submerged reefs, they lack hills or mountains, so radar must be placed at low altitude. Radar emits electromagnetic waves that propagate along the line of sight, meaning that Earth’s curvature limits the coverage of low-altitude radar installations.

This limited detection distance is known as the radar horizon. The AN/TPY-2 is reported to have a radar range of up to 3,000 km, but according to a calculation by Jaganath Sankaran and Bryan Fearey, it would have a maximum range of 800 km even under the most optimistic conditions.

Over-the-horizon (OTH) radars can detect beyond the radar horizon but are unsuitable for fire control. The best way to extend radar coverage is therefore to use external radar — such as airborne or space-based systems — and relay the data back to the shooter for target engagement.

Relaying targeting data from an external radar back to the shooter is known as cooperative engagement capability (CEC). Executing CEC is an extremely challenging task, given the dense networking it requires among different systems to form an effective system-of-systems.

One possible reason Iran was able to strike such a formidable radar system is that it was not integrated with other systems capable of protecting it against incoming threats. Radar, as an active emitter of electromagnetic radiation, is inherently vulnerable to counterattack and must be placed under a protective umbrella of airborne, naval or ground-based systems to defend against incoming threats.

The AN/TPY-2 was deployed at Muwaffaq Salti Air Base in Jordan, just over 800 km from Iran — within its reported radar range — yet it could not thwart the incoming attack. Although details of the Iranian strike remain unknown, integration with airborne or ground-based radar systems would have improved its chances of doing so.

A well-networked system-of-systems architecture is therefore indispensable for achieving information dominance — no individual system can perform at full potential in isolation, leaving exploitable gaps that only seamless integration can close.

China, however, has yet to integrate airborne, naval and ground-based radar systems for real-time operations. Although it has developed multi-layered, overlapping ISR coverage, without a well-networked system-of-systems architecture those systems can only operate in isolation, providing minimal support to one another.

This presents an opportunity for Southeast Asian claimant states, the United States and its allies to challenge China’s “informationized warfare” — and its EW capabilities — to prevent China from achieving information dominance in any SCS conflict.

Just as Iran was able to strike and destroy the AN/TPY-2 in Jordan, deployed without the protection of a well-networked system-of-systems architecture, China’s adversaries could exploit the same vulnerabilities to overwhelm its disjointed ISR capabilities in the SCS.

Harshit Prajapati is a PhD candidate at the Centre for Indo-Pacific Studies, Jawaharlal Nehru University, New Delhi.