THz atmospheric attenuation model

A model of the terahertz waves atmospheric transmission and attenuation is developed with the radiation transmission theory, continuum absorption and modified Van Vleck-Weisskopf line-shape based on the HITRAN database. The THz wave atmospheric attenuation experimental results obtained with the THz-time domain spectroscopy (THz-TDS) technique are analyzed by using this model, and the absorbing attenuation characteristics are compared. The influence of the humidity on the atmospheric attenuation is studied. The precision of the resulted theoretical attenuation is demonstrated by the good agreement between the calculation and the measurement, but a small discrepancy remains in the low-frequency atmospheric window.