title: FGG-NUFFT-Based Method for Near-Field 3-D Imaging Using Millimeter Waves.
abstract: In this paper, to deal with the concealed target detection problem, an accurate and efficient algorithm for near-field millimeter wave three-dimensional (3-D) imaging is proposed that uses a two-dimensional (2-D) plane antenna array. First, a two-dimensional fast Fourier transform (FFT) is performed on the scattered data along the antenna array plane. Then, a phase shift is performed to compensate for the spherical wave effect. Finally, fast Gaussian gridding based nonuniform FFT (FGG-NUFFT) combined with 2-D inverse FFT (IFFT) is performed on the nonuniform 3-D spatial spectrum in the frequency wavenumber domain to achieve 3-D imaging. The conventional method for near-field 3-D imaging uses Stolt interpolation to obtain uniform spatial spectrum samples and performs 3-D IFFT to reconstruct a 3-D image. Compared with the conventional method, our FGG-NUFFT based method is comparable in both efficiency and accuracy in the full sampled case and can obtain more accurate images with less clutter and fewer noisy artifacts in the down-sampled case, which are good properties for practical applications. Both simulation and experimental results demonstrate that the FGG-NUFFT-based near-field 3-D imaging algorithm can have better imaging performance than the conventional method for down-sampled measurements.
authors.affiliation: College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. kanyingzhi@nudt.edu.cn.
authors.forename: Yingzhi
authors.initials: Y
authors.lastname: Kan
authors.affiliation: College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. zoyofo@163.com.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. tangliangcool@163.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Tang
authors.affiliation: College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. fuqiang1962@vip.sina.com.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Fu
authors.affiliation: Beijing Institute of Mechanical and Electrical Engineering, Beijing 100074, China. peihch@163.com.
authors.forename: Hucheng
authors.initials: H
authors.lastname: Pei
keywords: 3-D imaging; FGG-NUFFT; millimeter wave; near-field