Detecting a target with quantum entanglement

In the last decade a lot of research activity focused on the use of quantum entanglement as a resource for remote target detection, i.e. on the design of a quantum radar. The literature on this subject uses tools of quantum optics and quantum information theory, and therefore often results obscure to radar scientists. This review has been written with purpose of removing this obscurity. As such, it recollects the main advances in the quantum radar literature accompanied by a thorough introduction of the quantum optics background necessary for its understanding.