低杂波多结波导阵天线耦合特性的数值分析

通过数值模拟研究了低杂波多结波导阵天线的耦合特性。采用线型耦合理论，用艾黎函数计算了等离子体阻抗，推导出常规波导阵对等离子体的散射矩阵，并利用它和天线自身的散射矩阵研究了HT-7装置低杂波多结波导阵天线的耦合特性；计算了其平均功率反射系数、方向性系数和功率谱与等离子体边缘密度和主波导相位差等参数的关系。结果表明，与常规波导阵相比，由于多结波导阵天线存在自匹配特性，其天线功率反射系数小，且对相位不敏感。但由于存在多余副瓣，驱动效率较低。

Numerical analysis on coupling properties of the LHCD multijunction launcher

The coupling properties of the Lower Hybrid Current Drive (LHCD) multijunction (MJ) launcher are investigated numerically. The Airy function is used to calculate the plasma impedance and the grill-plasma scattering matrix is deduced, then the coupling properties of the HT-7 LHCD MJ launcher are studied with the antenna scattering matrix and the grill-plasma scattering matrix based on the liner coupling theory. The average power reflection coefficient, directivity, power spectrum are obtained for different edge plasma densities and for different phasings between main waveguides. The results show that the power reflection coefficient of the MJ launcher is much lower and less sensitive to the phase difference than that of the conventional grill because of its self-matching characteristic. However, due to the excrescent side lobe, the current drive efficiency is lower.