Efficient MIMO Array 3D Fine Imaging Method with Adaptive Sub-scene Segmentation and Wavenumber Domain Born Approximation

Microwave fine imaging technology for multiple inputs and multiple outputs (MIMO) array radar has attracted considerable attention in security screening, owing to its high-resolution and non-harming characteristics. However, the large amount of millimeter-wave (MMW) MIMO echo data leads to huge computational overhead, making it difficult to obtain a real-time three-dimensional (3D) imaging result. To figure this out, this paper proposes an efficient 3D fine imaging method for MMW MIMO array radar based on adaptive sub-scene segmentation and wavenumber domain Born approximation (WDBA). Firstly, an efficient 3D reconstruction model is developed according to the Born approximation theory of wavenumber domain. Then, a 3D geometrical mapping from the WDBA imaging position to the true position is established to correct the 3D distortion caused by the first-order item of wavenumber domain Born approximation phase error (WDBAPE). Furthermore, an adaptive sub-scene segmentation and splicing strategy is adopted to eliminate the other items of WDBAPE with less computational overhead. Finally, to demonstrate the performance and feasibility of the proposed method, the real imaging experiments are conducted with an MMW MIMO array system using 1152 transmitting and 1152 receiving antennas within the 76GHz-81GHz frequency range.