太赫兹频段的目标散射特性测量技术是当前太赫兹雷达的重要研究方向，其中系统定标技术决定了雷达散射截面积(RCS)测量结果的准确性。使用基于微波倍频源的太赫兹宽带雷达目标散射特性测量系统，该系统由微波源经倍频后，中心频率达到440 GHz，带宽达25.6 GHz。利用光滑表面金属球为标准体，采用分时定标技术对太赫兹雷达系统进行定标，再对金属材质的战斗机模型和吉普车模型进行近场RCS测量实验，获得以上2种典型人造目标的近场RCS测量结果。测试结果与理论趋势符合良好，证明了太赫兹雷达系统RCS测量中分时定标技术的有效性。

Radar Cross Section(RCS) measurement under the terahertz band is one of the important research directions of terahertz radar. The system calibration technology determines the accuracy of the RCS measurement results. In this paper, RCS measurement system of terahertz wideband radar based on microwave frequency doubling source, the system has a central frequency at 440 GHz and its bandwidth is 25.6?GHz after the frequency doubled. Using a smooth surface metal sphere as the standard body, calibration of terahertz radar system by different times calibration technique, then the near field RCS measurement experiment of the fighter model and the jeep model of metal material are also carried out. Near field RCS measurements of two typical artificial targets have been obtained. The results are in good agreement with the theoretical trends, which proves the effectiveness of the time-sharing calibration technique in RCS measurement in terahertz radar systems.