This paper focuses on deriving expected values for the transmit (TX) and receive (RX) antenna gains in terahertz (THz) wireless fronthaul and backhaul links under stochastic beam misalignment, which is created by antenna movement coming from the building or antenna mast swaying. In particular, four different antenna movement models are considered: (i) Gaussian motion of a single antenna; (ii) Gaussian motion of both the TX and RX antennas; (iii) 2-dimensional (2D) Gaussian motion of a single antenna; and (iv) 2D Gaussian motion of the one antenna and one-dimensional Gaussian motion of the other. Models (i) and (iii) depict fronthaul scenarios, in which the access point is usually installed in high buildings or in road-sides. Models (ii) and (iv) may model backhaul applications. To verify the analysis and quantify the impact of beam misalignment, analytic and simulations results are provided that reveal that the antenna motion can cause a significant degradation on the expected value of the TX and RX antenna gains. Moreover, the derived models are used in a link budget assessment and insightful results for a number of realistic scenarios are given. These result clearly highlight the impact of beam misalignment in the received signal quality as well as the importance of taking into account the beam misalignment and using the correct antenna movement model, when evaluating its impact.

本文着重于在随机波束未对准情况下在太赫兹（THz）无线前传和回传链路中推算发射（TX）和接收（RX）天线增益的期望值，这是由建筑物或天线桅杆摆动引起的天线移动造成的。特别地，考虑了四个不同的天线运动模型：（i）单个天线的高斯运动；（ii）TX和RX天线的高斯运动；（iii）单个天线的二维（2D）高斯运动；（iv）一个天线的二维高斯运动和另一个天线的一维高斯运动。模型（i）和（iii）描绘了前传场景，其中接入点通常安装在高层建筑物或路边。模型（ii）和（iv）可以对回程应用程序进行建模。为了验证分析结果并量化光束未对准的影响，提供的分析和仿真结果表明，天线运动会导致TX和RX天线增益的期望值显着下降。此外，导出的模型用于链接预算评估中，并给出了许多实际情况的有见地的结果。这些结果清楚地突出了波束未对准对接收信号质量的影响，以及在评估其影响时考虑到波束未对准并使用正确的天线运动模型的重要性。