RCS measurement of cylinders in terahertz band based on the time-domain spectroscopy system

Radar cross section(RCS) measurement is of great significance to terahertz(THz) radar system design. Firstly, the principle and experimental design of RCS measurement based on time-domain spectroscopy (TDS) system were introduced. Secondly, by using TDS system, the time-domain echo of smooth and rough cylinder were obtained. The measured RCS value can be given after Fourier transform. Compared the measured value with the physical optics solution of the same size cylinder, the results shows that calculation and measurement have the same result which prove the TDS system can be used to measure RCS in terahertz band. Finally, comparison of measured RCS value between the smooth and rough cylinder indicates that the higher frequency, the greater impact of rough surface on RCS in terahertz band, and the traditional definition of rough surfaces which roughness more than one eight of the wavelength is not suitable any more.