Two-Dimensional Ultrawideband Radar Imaging of a Target With Arbitrary Translation and Rotation

Indoor target detection and imaging technologies hold great interest for security surveillance systems. The ultrawideband (UWB) radar is promising because it can complement conventional camera-based systems. However, conventional UWB radar imaging systems are costly and impractical because they require large antenna arrays for acceptable resolution. This paper proposes a low-cost UWB radar imaging method using the motion of a target. The method employs five antennas for estimating the motion of a target, including its rotation, to obtain an image. Previous work deals only with a target in translation without rotation, which makes the method difficult to apply in practice. The proposed method, an extension of such previous methods, obtains an accurate image for an elliptical or distorted nonelliptical target with arbitrary translation and rotation. Numerical simulation and experimental results show that the proposed method is capable of accurately estimating motions and shapes.