为测量太赫兹时域光谱散射测量系统的静区场强分布, 以确定后续测量目标的尺寸, 将金属球在静区三维方向上移动测量回波, 分别采用不同软件处理实验数据并得到不同类型的数据拟合曲线, 由拟合曲线得到了静区的三维空间范围。通过不同类型的曲线拟合发现, 相对于入射波方向在静区横截面的两维方向上, 电场强度分布近似为高斯分布, 而在入射波方向上的场强分布在某一范围内存在波动现象。还对系统的线性度进行了测量, 结果显示了系统具有良好的线性度。

The quiet zone of terahertz time-domain spectroscopy experiment system was measured, which was very important for targets measurements. Experimental data had been processed with software packages of MATLAB and Origin respectively and corresponding fitting curves were gotten as a result. Relative to the travelling direction of electromagnetic wave, different fitting formulas including Gaussian were found describing the electric field intensity distribution very well in the cross section of the quiet zone transversely and vertically. However, there was fluctuation in quiet zone longitudinally. Additionally, the linear relationship between peak scattered electric field and metal sphere diameter was studied with this experiments.