Beamforming Antenna Design for Uplink Cellular-Connected Unmanned Aerial Vehicle (UAV)

Unmanned aerial vehicles (UAVs) equipped with cellular connectivity have emerged as an innovative solution for various industries. However, cellular network antennas are designed to optimize ground-based transmission and are angled downwards, which can result in weakened uplink signals from high-altitude UAVs. To address this issue, the present study explores an effective beamforming antenna design using the Antenna Toolbox software package in MATLAB R2022a. The study aims to establish the reliable operational limits of cellular-connected UAVs by evaluating UAV performance through capacity analysis at diverse horizontal distances and altitudes. The study indicates that a microstrip patch antenna with a 2 × 2 array and antenna beamforming can enable the UAV to transmit uplink signals at high data rates. It is also revealed that the number of antenna elements needed and the antenna orientations that result in optimum performance are three microstrip patch antennas with orientations of 45°, 90°, and 135°, respectively. By implementing antenna beamforming, the overall capacity at the base station is greatest at a horizontal distance of 50 m and lowest at 1000 m. The capacity reaches its maximum at heights ranging from 70 to 80 m, which is close to the base station height (76 m) for all horizontal distances.