Design of Low-Cost On-board Auto-tracking Antenna for Small UAS

Unmanned Aerial Systems (UAS) are being used commonly for surveillance providing valuable video data. High quality video transmission is a must feature for this purpose. The radio signal from the UAS is transmitted generally over Omni-directional antennas, but the attenuation rate is very high and the transmission distance is severely limited. For achieving longer distance, directional antennas can be used where they should be pointing towards each other for maximum signal strength. A moving aircraft requires an antenna which dynamically points towards the ground control station (GCS). The tracking antennas currently being used are usually placed on the receiver side on the GCS and track the aircraft based on the signal strength. This method is inefficient when the aircraft movement is fast and makes it difficult to retrieve the aircraft related data once some snap occurs in tracking process. This research is aimed at developing a low cost precise tracking antenna which can be mounted onto any aerial system which needs long-distance video transmission. This system consists of inertial measurement unit, global positioning system, and servo motors to direct the antenna. It tracks the GCS using both the gyro sensor and GPS data such that even if one system fails, another one is available as a backup. This system implements tilt compensation in both x and y axis using the accelerometer in the IMU.