Characterisation of attenuation by sand in low-THz band

Abstract

Research to quantify the attenuation of 150 GHz and 300 GHz EM waves in sand has been conducted and the results are presented in this paper to investigate the performance of low-THz sensing for outdoor applications when a antenna radome might be contaminated by sand, which is one of the most common types of contaminant in outdoor environments. The signal power deviation has been studied as a function of sand thickness and granule size. Five kinds of granule-size-calibrated silica sands and natural sand were used in the experiment. While the results confirms expected greater attenuation at 300 GHz than that at 150 GHz, it has also been shown that sand composed of coarser particles provide greater attenuation than that of finer particles, which challenges some previously reported results.

Next Generation, Low-THz Automotive Radar - the potential for frequencies above 100 GHz

“…The results for sand in [9] indicate that coarser sand particles produce greater attenuation than finer particles. However, in practice sand with smaller particle sizes is more likely to attach to the radome, possibly forming a uniform layer.…”

Terahertz Communications and Sensing for 6G and Beyond: A Comprehensive Review

“…[146] Experimentally demonstrated the propagation of THz signals through 137 m of dense fog with approximate visibility of 7 m, and reported the observed THz attenuation. [147] Quantified the attenuation of 150 GHz and 300 GHz THz waves in the sand for the outdoor scenario of low-THz sensing. [148] Assessed the attenuation through various intensities of snowfall experimentally at 300 GHz, which is characterized by measuring the ratio of the received power from the target through the snow precipitation and through the same path with no precipitation.…”

Toward localization in terahertz-operating energy harvesting software-defined metamaterials

“…In more general terms, in the design of a system for localization in SDMs, one will have to account for the scattering and absorption losses from a particular surface, and the design of such a system will have to be environment specific for attenuation-heavy environments. Nevertheless, initial studies in the literature reports around 5 dB scattering and absorption losses for different types of sands [59], and less than 5.6 dB for losses in ordinary clothing materials [60], suggesting that for some of the potential use-cases the environment-specific design might not be needed.…”