Breaking News
China Develops a Near-Light-Speed Radar System to Counter Submarine Stealth.
Chinese scientists have developed a "ghost" radar capable of emitting electromagnetic waves at speeds close to the speed of light, enabling submarine detection. This innovation is based on the advanced use of the Doppler effect and high-energy microwave synthesis, as detailed in a study published on November 28, 2024, in the Chinese academic journal Modern Radar.
The Chinese Academy of Sciences designed a virtual radio emission source in the sky that generates continuously moving extremely low-frequency (ELF) electromagnetic capable of penetrating seawater and effectively detecting submarines several hundred meters below the surface. (Picture source: China Military)
The team, led by Li Daojing of the National Key Laboratory of Microwave Imaging at the Chinese Academy of Sciences, has designed a virtual radio emission source in the sky. This constantly moving source continuously generates extremely low-frequency (ELF) electromagnetic waves capable of penetrating seawater to detect submarines several hundred meters below the surface. These ELF signals, with wavelengths exceeding 100 meters, allow for effective submarine detection due to their interaction with the aquatic environment.
The researchers describe this technology as capable of transforming underwater detection. When ELF signals at 100 Hz interact with a nuclear submarine, its radar cross-section (RCS) can reach up to 88 square meters, enabling identification using standard magnetic detectors. Compact detectors mounted on drones could achieve gradient detection across wide areas, providing extensive and precise coverage.
Traditionally, ELF signals required massive antennas, such as the ELF facility in central China, which spans over 100 km. Li Daojing's team has significantly reduced the size of these structures. Their new transmitter, measuring only 100 meters in length, is compact enough to be installed on Chinese naval ships. The high-frequency, high-power microwaves emitted by these antennas converge in the sky to form a virtual radio source. As one source dissipates, another is instantly generated, creating a continuous flow of ELF signals.
This technique employs a network structure to simulate high-speed motion using Doppler signals in space. It reduces signal frequency while widening pulse width. The Doppler effect—where wave frequency changes based on relative motion between the source and observer—is a fundamental principle of this development. The perceived frequency increases as the source and observer approach each other and decreases as they move apart.
Beyond submarine detection, the technology has potential applications for communication between surface ships and submarines, with an estimated range of 6,000 kilometers. Following successful ground-based trials, the team plans to reduce the transmitter's size to about 30 meters, making it more adaptable for various uses.
This development was achieved with contributions from institutions such as the China Electronics Technology Group and Northwestern Polytechnical University, both key players in advanced military technologies for the People’s Liberation Army. The research highlights the integration of scientific innovation with strategic application to enhance underwater detection and communication capabilities.
The innovation aligns with China's strategic priorities amid Sino-American rivalries, particularly regarding Taiwan and regional maritime security. While still in development, the technology could bolster China's ability to monitor and control its maritime zones, potentially affecting the strategic balance with the United States and its allies. By improving submarine detection, China aims to safeguard its territorial interests and assert its presence in the South China Sea, a region of heightened tensions surrounding Taiwan. This technological progress could reshape maritime security dynamics and influence submarine operations by external forces, reinforcing China's regional claims.