On the problem of high-accuracy modeling of the dry air absorption spectrum in the millimeter wavelength range

Abstract A detailed analysis of the dry air spectrum in the frequency range 180–260 GHz is given. The contributions of monomolecular and bimolecular absorption are discussed. It is shown that the effect of collisional coupling of zero-frequency transitions has a significant impact (up to 60%) on the value of nonresonance absorption. The coefficients of the empirical approximation of the "dry" continuum are redefined. A comparison with the continuum approximation from the Millimeter-wave Propagation Model is given.