Researchers working for the US military recently developed a quantum sensor capable of precisely analyzing the radio frequency spectrum. However, we are talking about a very wide range. According to the US Army, this type of device could allow listening to enemy communications. It could also mean maintaining its own operations in the face of jamming systems.
Radio spectrum coverage up to 20 GHz!
It is possible that in the more or less near future, quantum technologies could make their appearance on the battlefield. For now, quantum is used in cryptography, but could well relate to communications on the ground, at sea or in the air. In a report published in the journal Applied physical examination on January 27, 2021, scientists from the US Army Research Laboratory detailed their latest innovation. We are talking about a new sensor capable of detecting the entire radio spectrum up to 20 GHz. However, this spectrum covers among others Wi-Fi, Bluetooth and many other means intended for communication.
Researchers explained that they had exploited rubidium atoms in Rydberg state. Going into the use of quantum computers, these atoms are very sensitive to electromagnetic waves. Under the effect of an excitation, they therefore enter this state making it possible to identify and then analyze the waves.
An improvement of an existing technology
Scientists at the US Army Research Laboratory described how a laser could to excite rubidium atoms in a vacuum chamber, the goal being to force them to enter a Rydberg state. The sensor collects the input radio waves, before processing them in a microwave system. Next, algorithms are responsible for fine-tuning and increasing the sensitivity to the desired areas of the radiofrequency spectrum. This kind of quantum sensor has been around for several years, but research had only resulted in the detection of small areas. Thus, recent research has broadened the possibilities to cover a wide range with precision.
Project officials said their innovation could detect enemy communications. It is also about protecting communication systems against jammers and other interference. On the other hand, this quantum sensor, which is still in development, is – in its current state – quite simply unusable on a battlefield. Indeed, the latter is too bulky, but also energy intensive. Researchers will have to find solutions miniaturization and energy saving in order to allow integration of their innovation into army equipment.