【摘要】 在理想导电地面与电离层条件下,我们导出了SLF/ELF垂直电偶极子在球形地-电离层壳体中产生的电磁场的球谐级数表达式,并提出了一种加速收敛算法。利用此算法分别算出了电场分量随传播距离、高度及工作频率的变化,所得计算结果与Barrick方法所得结果基本吻合。由于地面和电离层没有吸收损耗,地面与电离层之间产生的场是"驻波",在ELF频段,其频率变化规律能正确反映出"舒曼"谐振现象。更多还原

【Abstract】 We derive the spherical harmonic series expressions of electromagnetic fields excited by SLF/ELF vertical electric dipole in spherical Earth-ionosphere guide when earth and ionosphere are regarded as the ideal conductor.Moreover,a method to speed numerical convergence has been presented.The electromagnetic fields in the cavity have been calculated by this algorithm.From the result,electromagnetic fields between earth and ionosphere are the sum of two travelling wave in SLF band.The calculated result perfectly agrees with the Barrick’s result.Because there is not absorbability attenuation between the earth and ionosphere,the fields in Earth-ionosphere guide are a kind of standing wave.In ELF band,the variation of the amplitude verse frequency coincides with the Schumann resonance.更多还原