Because the oversized, ultra short-range and arbitrary-shape goals cannot be imaged by Fourier transform algorithm, a Boundary Element Method(BEM) is presented for short-range millimeter wave holographic imaging.Through the discrete boundary integral equation, the discrete electromagnetic fields on the source surface and holographic surface are obtained. They are linked by a transfer matrix. Finally, the discrete electromagnetic fields obtain target holographic image. Due to the complexity of the transfer matrix, the Distributed Source Boundary Point Method (DSBPM) is introduced to calculate it, which greatly simplifies the calculation process. The simulation experiments of three-dimensional hemisphere imaging show the sensitivity of the imaging algorithm to test error, and regularization method has been proposed. The actual measurement of the four small metal balls verifies the validity of the imaging algorithm for large target imaging. The imaging results show that holographic imaging of the boundary element method can obtain high resolution and high amplitude accuracy.
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