Fast Processing Approach for Near-Field Terahertz Imaging With Linear Sparse Periodic Array

The benefits of terahertz (THz) radiation have increased its use, especially in imaging systems. Recently, the use a linear sparse periodic array (SPA) has been proposed as an effective solution for two-dimensional (2D) scanning THz However, special multistatic structure SPA is such that it not possible to apply fast Fourier transform-based techniques directly near-field (NF). Therefore, this paper, processing approach based on two compatible with presented NF imaging. In approach, we first employ multistatic-to-monostatic conversion reduce phase errors due Then, improve quality results, mathematically derive interpolation formula counteract non-uniform spacing virtual array. modified data then processed by three rapid (fast transform (FFT)-inverse transform, matched filtering and novel 1D FFT-based technique low computational complexity) obtain reconstructed images scene. Numerical experimental results confirm satisfactory performance terms both time images.