Research on Radar Cross Section Measurement Based on Terahertz Radar Near-Field High Resolution Imaging

Radar cross section (RCS) measurement is an important way for understanding terahertz scattering characteristics of targets. Terahertz RCS measurement has high requirements for the background environment. This paper proposes a RCS measurement method based on terahertz near-field high resolution imaging system. Firstly, a convolution back projection algorithm model for near-field compensation is proposed to achieve precise imaging of targets with large rotation angle. Then, different window functions in image domain are designed to extract the target’s scattering distribution and filter out the background interference. Finally, the RCS is retrieved through inverse Fourier transform of the extracted scattering distribution. By measurement of several typical targets, it is shown that the proposed measurement method can obtain the RCS of the targets at different angles through a single 360° rotation imaging, and the accuracy of RCS measurement is improved and the dynamic range of measurement is expanded obviously.