Broadband One-dimentional Range Profiles of Rough Surface in the Terahertz Range

The one-dimensional (1D) range profile is an important back scattering characteristic of objectives, which reveals the longitudinal distribution radar cross section (RCS) along detection beam. Since shape and posture can be reflected by 1D profile, it great significance in military to determine target orientation, velocity whether armed. In this paper, broadband terahertz 1D-range-profile measurement was enable based on time-domain spectroscopy (TDS) system. It bistatic configuration (bistatic angle 9°) signal-to-noise ratio (SNR) 34.5 dB using a gold mirror as reflector. Benefiting from ultrashort pulse width (full 0.52 ps), bandwidth covered frequency 0.1 THz 2.5 (peaked at 0.9 THz), corresponding resolution submillimeter scale. Firstly, profiles several objects different shapes were measured, including step, cylinder, step cone their combinations, indicated that geometric targets direction adequate identify features proved reliability measuring system TDS. Secondly, aluminum plates with surface roughness 0~25 μm also characterized. Kirchhoff approximation theory small perturbation method (SPM) introduced illustrate characteristics related targets. found metal sensitive roughness. If object larger, peak intensity would weaker echo signal becomes wider. rule applicable for cases incident angles. Furthermore, revealed time delay systems rotation target, useful estimating target. summary, relating shape, are studied. conclusions should helpful identification radar.