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A new radar under development is expected to detect low observable (stealth) targets under electronic warfare conditions and identify stealth aircraft and missiles. Radar jamming is a form of electronic countermeasures (ECM), designed to degrade the effectiveness of enemy radar systems. Usually, this is done by emitting radio signals at specific frequencies which impair the ability of radar systems to accurately detect and depict objects in the operational environment.
China claims to have revealed a prototype of an advanced quantum radar that is resistant to jamming and may be able to detect stealth aircraft. The system’s operation is rooted in proven science and could be game-changing, but the Chinese still face significant development challenges in turning it into an operational capability.
The state-owned China Electronics Technology Group Corporation (CETC) revealed a mockup of their quantum radar.
While a traditional radar emits a beam of electromagnetic energy, which then reflects off objects in the distance, allowing the entire system to register their return signature and position with varying degrees of specificity, a quantum radar does essentially the same thing, but differently. It uses photons that are “entangled” together after a single beam of light is split in half. One of the two new beams passes through a converter that sends the particles traveling onward at a microwave frequency to bounce off objects like a normal radar. The full system would convert the particles back into the visible frequency as they returned to the radar’s receiver. The second beam serves an immensely important purpose. A phenomenon called quantum entanglement means that the pairs of photons that appear at the point a beam of light is split otherwise have a tendency to operate identically regardless of how far they are apart.
What this means is that the quantum radar should be able to register the paired photons in both streams and record only the signals it gets back from particles that have a partner. This would make the system more accurate since it would be able to quickly eliminate signals from other sources, such as ground clutter when tracking targets at low altitude or operating in a maritime role, according to a report by thedrive.com.
The quantum radar should is also expected to be able to identify stealth planes, missiles, and ships. Existing radar absorbent materials are not specifically designed to absorb or defuse these particles. Stealthy shapes might still deflect the photons and cause them to lose energy to some degree, but the system’s ability to isolate only the activities of the entangled photons theoretically means that it should be able to detect even a very weak signal by cutting out all of the background noise.
CETC claims that it has been working on the system for years and first tested it in 2015.