大气对太赫兹辐射传输存在一定的非协作性，即存在吸收衰减。为了实现太赫兹辐射的有效应用必须细致地了解太赫兹辐射大气传输的窗口位置、宽度及大气透过率。选取了处理大气非均匀路径、吸收带重叠等大气辐射传输问题的最精确方法——逐线积分法，发展计算程序，并基于HITRAN分子谱线数据，对水汽、氧气、臭氧、氮气、二氧化碳等单组分气体分子对太赫兹辐射传输的吸收衰减情况进行了计算与分析，并给出了在太赫兹电磁波大气传输衰减中占主要因素的水汽和氧气的衰减峰位置。

The atmosphere is opaque to terahertz wave, hence knowing accurately the location and width of atmospheric transmission windows is crucial to facilitating any type of applications utilizing THz technology. In this paper, the line-by-line integral method is used to calculate the THz atmospheric transmittance attenuation. Based on the molecular line data provided by HITRAN 2008 database, the calculation results of the attenuation characteristics of H2O, O2, O3, CO2 and N2 gas with certain density, temperature and pressure are presented and discussed. The results indicate that vapor and oxygen contribute the most to THz transmittance attenuation under the natural conditions in the 0-3 THz range.