New possibilities and challenges for imaging radar

In 1984, a forward-looking paper by Dale Ausherman was titled: "Devel- opments in Radar Imaging" [1]. Now, 22 years later, we have not reached the end of these developments: new technological possibilities and new insights into the na- ture of radar imaging allow exciting novel techniques and applications. The digital revolution today bestows a much larger flexibility to use radar in a smart manner: programmable and reconfigurable. Multi-channel and multi-sensor data acquisition together with electronical beam steering make possible extremely involved engineering ideas. On the other hand, these new possibilities implicate new challenges, e.g. they force to establish new processing techniques, highly accurate calibration and motion measurements. In this paper, we will touch some new possibilities opened in the last few years and the challenges connected to them.