Fast Integral Method For Near-Field Cross Section Imaging At Millimeter Wave

Near-field cross section imaging is an important issue for near filed radar imaging. Conventional methods always transform the recorded data to the frequency wavenumber domain and utilize interpolation and fast Fourier transforms (FFT) to reconstruct image. Since the interpolation accuracy significantly affects the image quality especially when the spatial spectrum data is highly curving in the case of wideband millimeter wave. To avoid interpolation and consider the calculation efficiency, a fast integral imaging method is proposed. The imaging formula is derived from the echo signal model. A two dimensional integral obtained by back projection theory is transformed into a one-dimensional FFT and a one-dimensional integral which guarantee accuracy and efficiency. Simulation is carried out to certify the effectiveness and efficiency of the method.