Efficient Near-Field Imaging Using Cylindrical MIMO Arrays

Multiple-input–multiple-output (MIMO) array-based millimeter-wave (MMW) imaging has a tangible prospect in applications of concealed weapons detection. A near-field imaging algorithm based on wavenumber domain processing is proposed for a cylindrical MIMO array scheme with uniformly spaced transmit and receive antennas over both the vertical and horizontal-arc directions. The spectrum aliasing associated with the proposed MIMO array is analyzed through a zero-filling discrete-time Fourier transform. The analysis shows that an undersampled array can be used in recovering the MMW image by a wavenumber domain algorithm. The requirements for the antenna interelement spacing of the MIMO array are delineated. Numerical simulations as well as comparisons with the backprojection algorithm are provided to demonstrate the effectiveness of the proposed method.