FMCW Radar Near Field Three-Dimensional Imaging

A system with 3-D imaging capability can be implemented by using a frequency modulated continuous wave (FMCW) radar which synthesizes a two-dimensional (2-D) planar aperture. A millimeter-wave FMCW three-dimensional (3-D) imaging system can be used for the detection of concealed weapons and contrabands at airports or other security checkpoints, since millimeter-wave can readily penetrate common clothing material. A 3-D image can be formed by coherently integrating the backscatter data over the measured frequency bandwidth and the two spatial coordinates of the 2-D synthetic aperture. This paper presents a 3-D imaging algorithm for near field FMCW radar. This algorithm is an extension of the 2-D range migration algorithm (RMA). We derive the formulation in detail by using the principle of stationary phase (POSP). A 3-D version Stolt interpolation is used in this algorithm. Accurate image reconstruction and high computational efficiency of this algorithm are demonstrated through simulation results.