短語(yǔ)詞組短語(yǔ)tpt propagation delay time 傳播延時(shí)propagation time delay 傳播時(shí)間延遲英語(yǔ)Propagation Delay Time HIGH -to-LOW Level 傳播延遲高到低Propagation Delay Time LOW -to-HIGH Level 傳播延遲低到高Propagation time -delay of ground-wave 地波傳播時(shí)延 返回 propagation delay time