Mitigating the effects of water vapour absorption within terahertz wireless communication systems

Communication technology has shown trends towards wireless systems (for improved mobility) and broader bandwidths (for high data rates). This has led to growing interest in terahertz (THz) wireless communication systems—for which there are great benefits and equally great challenges. Arguably, the single greatest challenge for THz wireless communication systems is the susceptibility of the THz spectrum to water vapour absorption in the free-space/air environment. Our study recognizes this challenge and introduces a physical model through which the water vapour characteristics can be fit and then removed from measured signal characteristics. We show the physical foundations of our model and demonstrate its effectiveness in fitting the water vapour characteristics in measured signals from a THz time-domain spectroscopy system. The theoretical and experimental results show strong agreement, suggesting that the model can be an effective tool for characterizing and mitigating the effects of water vapour absorption in future THz wireless communication systems.