摘要
首先,采用勒让德多项式的加法定理,对PartⅠ部分得到的并矢格林函数进行化简,将双级数和形式转换成单级数和形式。然后,将场型格林函数转换成位型格林函数,将九个分量中收敛慢的TM分量统一合并成公共的标量位函数。接着,利用球贝塞尔函数和汉克尔函数的渐近公式,导出并矢格林函数的渐近函数,以加速格林函数的收敛速度。最后,计算了球面共形微带天线的输入阻抗,与文献计算结果吻合,说明了处理的正确性和有效性。
Firstly,the dyadic Green's functions obtained in PartⅠ are reduced to a single summation from double summation expressions based on the addition theorem of Legendre polynomials. Then,the field Green' functions are converted to the potential Green's functions,and the slowly convergent modes TM in nine elements are incorporated into a unified potential. Next,the asymptotic items of the dyadic Green's functions are attained to accelerate the infinite series convergence using the asymptotic expressions of spherical Bessel and Hankel functions. Finally,the input impedance microstrip antennas in multilayered spherical media are calculated,and the results are in good agreement with ones from literatures,which shows the validity and effectiveness of the analysis method.
引文
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