Calculating Terahertz Channel Capacity Under Beam Misalignment and User Mobility

In this letter, we consider the terahertz (THz) wireless communication between an unmanned aerial vehicle (UAV) and a base station. The beam alignment is interrupted by some unpredictable factors, such as air turbulence, and the UAV recovers the beam alignment via flying maneuver. Here, we propose a new method to obtain the closed-form channel capacity under the beam misalignment, where a classical control model is used to capture the trajectory of the UAV maneuver. This allows us to obtain a much accurate channel capacity compared with the conventional methods that treat the misalignment as a random variable. The numerical results show that the proposed method reduces almost 80% calculation error compared to the conventional method.