1)  travel time
双程走时
2)  two-way
双程
3)  double-pass forward
双程前向
4)  Round trip time
双程时延
5)  two-way propagation
双程传播
1.
Theoretical analysis of Faraday rotation for trans-ionosphere two-way propagation;
穿越电离层双程传播法拉第旋转的理论分析
6)  two-stage double-pass
双级双程
1.
The basic principle of L-band is presented,based on 3 dB wide band coupler,the fiber loop mirror with high reflectivity is obtained,through optimal designs and experiments,the two-stage double-pass of L-band with high power amplified spontaneous emission(ASE) fiber source was developed.
研究了L波段光产生的基本机理,基于3dB宽带耦合器的光纤环形镜作为反射镜,优化设计并通过实验得到了双级双程L波段掺Er光纤(EDF)高功率放大的自发辐射(ASE)输出光谱。
参考词条
补充资料：程程
1.旅途停顿处。 2.一程又一程。谓路程遥远。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。