Beam propagation method (BPM) is employed to calculate the coupling coefficient of transmission modes in MMF coupler, and an output pattern from coupling branch is obtained.是什么意思_Beam propagation method (BPM) is employed to calculate the coupling coefficient of transmission modes in MMF coupler, and an output pattern from coupling branch is obtained.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句