Beyond Visual Line of Sight UAV Control for Remote Monitoring Using Directional Antennas

Many new Unmanned Aerial Vehicle (UAV) applications require beyond visual line of sight (BVLOS) control of UAVs. Examples include UAV-based nondestructive health monitoring of civil infrastructures and remote UAV-assisted emergency response. In this paper, we develop a BVLOS control solution for a remote UAV, using a local UAV relay equipped with automatically aligned directional antennas. The use of UAV relay permits flight control signals to be transmitted even if there exists blockages between the remote UAV and its operator. The use of directional antennas extends the UAV control distance to kilometers with high data throughput. Built upon our previously developed aerial communication system using directional antennas (ACDA), we first upgrade the hardware and software to improve the throughput and endurance. We then design and implement a BVLOS control solution which includes a two-way relay communication. In one direction, low-resolution video views from the remote UAV are transmitted through the local UAV relay to help a UAV operator navigate the remote UAV. In the other direction, UAV control signals are relayed through the local UAV and transmitted to the remote UAV for BVLOS operations. The system is verified using simulation studies and field tests.