Sommerfeld's wave expansion theory demonstrates that a spherical wave can be expanded as the superposition of plane simpleharmonic waves.
索末菲关于波的展开理论证明，球面波可以展开为平面简谐波的叠加。
2
The wave equation having general forms of planar simpleharmonicwave is deduced in this article. It is simple and accurate to solve wave equation by using this formula.
推导出了具有一般形式的平面简谐波的波动方程，利用此公式求解波动方程简单而且准确。
3
Transient and surge are the instant aberrance of the voltage and electric current on the simple alternating current wave circuit. surge and harmonic wave are the main manifestation.