用自由空间法测量材料复介电常数的研究

分析电磁波在自由空间通过平板电介质材料的传播特性,得到了散射参数与复介电常数之间的关系式和求解复介电常数的三种表达式,并对三种表达式分别进行误差分析.解决自由空间法测量电介质材料复介电常数的不稳定性问题和相位模糊性问题.建立测试系统,并在X波段对平板电介质材料进行测量.实验结果表明,本测试方法和测试系统是正确的.

Study of Using Free-Space Method for Measuring Complex Permittivity

The characteristic of electromagnetic wave through the dielectric planar sample in free-space was analyzed. The relations between the scatter parameters and the complex permittivity were found, and three expressions were obtained to determine the complex permittivity. The error analysis of these three expressions was performed. By combining these three expressions, instability problem and phase-shift ambiguity problem of thick samples were solved. The test system was established and several samples were measured at X-band. The validity of the method and test system was proved by experiments.