Taleb Fatima, Alfaro-Gomez Mariana, Al-Dabbagh Mohanad Dawood, Ornik Jan, Viana Juan, Jäckel Alexander, Mach Cornelius, Helminiak Jan, Kleine-Ostman Thomas, Kürner Thomas, Koch Martin, Mittleman Daniel M, Castro-Camus Enrique
Department of Physics and Material Sciences Center, Philipps-Universität Marburg, Renthof 5, 35032, Marburg, Germany.
Universidad Autonoma de Aguascalientes, Av. Universidad 940, Cd. Universitaria, 20100, Aguascalientes, Mexico.
Sci Rep. 2023 Nov 27;13(1):20782. doi: 10.1038/s41598-023-47586-8.
As the need for higher data rates for communication increases, the terahertz (THz) band has drawn considerable attention. This spectral region promises a much wider bandwidth and the transmission of large amounts of data at high speeds. However, there are still challenges that need to be addressed before the THz telecommunications technology hits the consumer market. One of the recurring concerns is that THz radiation is greatly absorbed by atmospheric water-vapor. Although many studies have presented the attenuation of THz signals under different atmospheric conditions, these results analyze specific temperature or humidity values, leaving the need for a more comprehensive analysis over a wider range of climate conditions. In this work, we present the first study of the attenuation of THz radiation over a broad range of temperatures and humidity values. It is worth noticing that all of our measurements have been undertaken at atmospheric pressure unlike many previous studies where the pressure was not kept constant for various temperatures. Furthermore, we extend our analysis beyond the impact of absolute humidity on the bit error rate in THz communications. We also discuss the refractivity of the atmosphere, examining its variations across different temperatures and humidity levels. THz propagation is studied using two different measurement systems, a long-path THz time-domain spectrometer as well as a quasi-optic setup with vector network analyze. We also compare the results with the ITU-R P.676-13 propagation model. We conclude that the attenuation at the absorption peaks increases linearly with water content and has no dependence on the temperature, while the refractive index, away from absorption lines, namely at 300 GHz shows a sub-linear increase with humidity.
随着通信对更高数据速率的需求不断增加，太赫兹（THz）频段已引起了广泛关注。这一光谱区域有望提供更宽的带宽，并能高速传输大量数据。然而，在太赫兹电信技术进入消费市场之前，仍有一些挑战需要解决。一个反复出现的问题是，太赫兹辐射会被大气中的水汽大量吸收。尽管许多研究已经给出了不同大气条件下太赫兹信号的衰减情况，但这些结果分析的是特定的温度或湿度值，因此需要在更广泛的气候条件范围内进行更全面的分析。在这项工作中，我们首次对太赫兹辐射在广泛的温度和湿度值范围内的衰减进行了研究。值得注意的是，与许多之前在不同温度下未保持压力恒定的研究不同，我们所有的测量都是在大气压下进行的。此外，我们的分析不仅限于绝对湿度对太赫兹通信中误码率的影响。我们还讨论了大气的折射率，研究了其在不同温度和湿度水平下的变化。使用两种不同的测量系统研究太赫兹传播，一种是长路径太赫兹时域光谱仪，另一种是带有矢量网络分析仪的准光学装置。我们还将结果与ITU-R P.676-13传播模型进行了比较。我们得出结论，吸收峰处的衰减随含水量呈线性增加，且与温度无关，而远离吸收线（即300GHz处）的折射率随湿度呈亚线性增加。
