Comparison of the influence of Martian and Earth's atmospheric environments on terahertz band electromagnetic waves

Abstract

SummaryTerahertz waves have wide application prospects in space communication because of their strong penetration ability, wide band, and strong directional antenna. Therefore, it is necessary to study the propagation characteristics of terahertz waves in space, such as in the environment on Mars. In space near Mars, the terahertz link is mainly affected by the absorption attenuation of its atmosphere and the scatter attenuation of heavy dust storms. In this paper, the absorption of 0.1–1 THz waves in the Martian atmosphere is analyzed. The absorption coefficient is calculated based on the theory of atmospheric radiative transfer and the HITRAN database. The influence of temperature, pressure, and altitude on the absorption coefficient is analyzed, and the calculation results are compared with those of Earth's atmosphere. The size distribution of Martian dust particles is then fitted by lognormal distribution, and the transmission characteristics of terahertz waves with different wavelengths are studied based on Mie theory. The research results show the transparent window positions of the attenuation peaks of water vapor and oxygen, which are the main factors of atmospheric transmission attenuation in the 0.1–1 THz band. The attenuation of Martian dust is affected by the size parameter, and it decreases with the visibility of the dust storm. The results provide a reference for terahertz communications in a Martian atmospheric environment and clarify the range of Martian atmospheric fading and dust fading.