title: Design and Imaging of Ground-Based Multiple-Input Multiple-Output Synthetic Aperture Radar (MIMO SAR) with Non-Collinear Arrays.
abstract: Multiple-Input Multiple-Output (MIMO) radar provides much more flexibility than the traditional radar thanks to its ability to realize far more observation channels than the actual number of transmit and receive (T/R) elements. In designing the MIMO imaging radar arrays, the commonly used virtual array theory generally assumes that all elements are on the same line. However, due to the physical size of the antennas and coupling effect between T/R elements, a certain height difference between T/R arrays is essential, which will result in the defocusing of edge points of the scene. On the other hand, the virtual array theory implies far-field approximation. Therefore, with a MIMO array designed by this theory, there will exist inevitable high grating lobes in the imaging results of near-field edge points of the scene. To tackle these problems, this paper derives the relationship between target's point spread function (PSF) and pattern of T/R arrays, by which the design criterion is presented for near-field imaging MIMO arrays. Firstly, the proper height between T/R arrays is designed to focus the near-field edge points well. Secondly, the far-field array is modified to suppress the grating lobes in the near-field area. Finally, the validity of the proposed methods is verified by two simulations and an experiment.
authors.affiliation: School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. hucheng.bit@gmail.com.|Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing 100081, China. hucheng.bit@gmail.com.
authors.forename: Cheng
authors.initials: C
authors.lastname: Hu
authors.affiliation: School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. ryan1312@foxmail.com.|Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing 100081, China. ryan1312@foxmail.com.
authors.forename: Jingyang
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. tianwei6779@163.com.|Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing 100081, China. tianwei6779@163.com.
authors.forename: Weiming
authors.initials: W
authors.lastname: Tian
authors.affiliation: School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. zengtao@bit.edu.cn.|Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing 100081, China. zengtao@bit.edu.cn.
authors.forename: Tao
authors.initials: T
authors.lastname: Zeng
authors.affiliation: School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China. bit.wangrui@gmail.com.|Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing 100081, China. bit.wangrui@gmail.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
keywords: MIMO imaging; MIMO radar; grating lobes; height difference between T/R arrays; near-field imaging