ISAR imaging of flying helicopters at millimeter-wave frequencies

The advantages of radar systems operating at millimeter-wave frequencies can be used for imaging flying objects, e.g. helicopters, by means of the ISAR principle. Using this technique it is possible to deliver a data base, which contains high resolution scatterer distributions of different targets and for different aspect angles. Under civil war conditions this data can he compared with ISAR images of approaching targets in order to distinguish between friendly and threat vehicles.