When the frequency is below than the cut-off frequency of the waveguide, the field intensity decays exponentially with distance along the waveguide and the wave is called evanescent wave.是什么意思_When the frequency is below than the cut-off frequency of the waveguide, the field intensity decays exponentially with distance along the waveguide and the wave is called evanescent wave.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句