Terahertz radar ultrahigh resolution imaging method

Abstract

The invention belongs to the technical field of radar signal processing, and particularly relates to a terahertz radar ultrahigh resolution imaging method. Terahertz frequency band target scattering energy anisotropy is relatively violent. The common method for imaging the target comprises the step dividing a large aperture into small apertures and jointly imaging sub-aperture images, and the smaller the sub-aperture is, the clearer the details in the small aperture is. The method of the invention is characterized in that in the sub-aperture dividing process, an algorithm based on a sub-aperture cross correlation coefficient in combination with sub-aperture energy is adopted to determine sub-aperture boundaries, and in the sub-aperture dividing method, the technology that the sub-aperturesare sequentially overlapped by a part is adopted. According to the method, the problem of sidelobe defocusing when small-aperture sub-aperture combined imaging is adopted for a scattered energy anisotropic target is better solved. The method solves the problem that when small-aperture sub-aperture combined imaging is adopted for a scattering energy anisotropy target, imaging details are incomplete due to the fact that edge angle scattering energy is cut off by aperture edges.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing, and in particular relates to a terahertz radar ultra-high resolution imaging method. Background technique [0002] For the imaging of targets with anisotropic scattering energy, if the coherent accumulation imaging of wide-aperture data is directly used, the strong scattering energy of the scatterers is only concentrated in a small part of the aperture, which will reduce the signal-to-noise ratio of the target and blur the edges and corners of the target. . The traditional imaging method for imaging targets with anisotropic scattering energy is: divide the wide aperture into multiple sub-apertures with fixed centers and equal widths, and non-correlationally combine these sub-aperture images to form a fusion image based on the GLRT imaging method, and the sub-aperture width The smaller the aperture, the clearer the details. Because terahertz radar has the disadvantage of more int...

AI Technical Summary

Problems solved by technology

The realization of this technology depends on a certain chance, so the imaging effect is unstable

At the same time, this technology only images sub-apertures with higher energy, but actually loses a lot of imaging details, and cannot achieve ultra-high resolution imaging.

And the sub-aperture energy is used to divide the sub-aperture, and then unifying the sub-aperture width does not set the sub-aperture boundary at the most reasonable position, resulting in this method not completely solving the sidelobe defocus problem of small-aperture sub-aperture division imaging, and the imaging effect is somewhat blurred

Images