短語(yǔ)詞組短語(yǔ)round -trip transit time 往返躍遷時(shí)間;往返增益Round -trip time on the road 來(lái)回路上時(shí)間fixed round -trip time 固定往返時(shí)間RTT round -trip time 來(lái)回時(shí)間 返回 round-trip time