Chinese military scientists have developed an intriguing contraption much to the surprise of its Western counterparts, an invisibility cloak that can hide ground military targets from spy radar satellites. The contraption is a piece of stretchable cloth that can fit over a range of various military equipment like artillery, radar station or tanks, almost perfectly.
This extraordinary flexibility of the cloak allows it to make the object almost invisible even to radar satellites, as per lead researcher Xu Hexiu whose team at the Air Force Engineering University at Xian, Shaanxi province, developed the cloak. In a paper published in the Journal of Infrared and Millimetre Waves last month they wrote that any target using or wearing the cloak would appear as if it is "a piece of land with nothing on it."
As reported by the South China Morning Post, the cloak explained by Xu and his colleagues has several layers, the top most being a thin fabric with several printed circuits, made by using a special 3D-print technology, that can manipulate electromagnetic waves. More layers include plastic and thin metals referred to as the "meta surface" that has the ability to shift the direction of a return signal in order to imitate the radar signature of flat land.
When the device was tested in a simulation facility the researchers observed that the waves that strike the cloak bounce back in a uniformed manner very identical to that from flat lands. As opposed to the situation when the waves strike an uneven object and return in a scattered manner. This led them to the conclusion that bigger the distance from the radar, smaller will be the disruption.
Xu added that the cloak no matter how efficient in its operation does not function as an independent device or item. "It needs to work with other methods including heat reduction, optical camouflage and decoys to achieve the desired effects," he said.
According to the researcher, many metamaterials have been developed in the recent years to deceive a radar satellite but they could not move like the cloak, without any restriction or limitation. The scientists have revealed that the technology can counter the effect of satellite radars altering the strength and angle of their beams to disclose details about any target.
