Performance Investigation of Link Failure Line-of-Sight (LOS) Communication UAV

In this paper, telemetry performance between UAVand GCS is examined by evaluating RSSI values of UAV and GCS during flight. The research aims to review the performance of telemetry communication between UAV and GCS during operation. Several parameters, such as airspeed, altitude, power, and range or GPS locations are analyzed to obtain relation to RSSI of UAV. The telemetry module uses RFD900P on both sides. There are external and internal factor that caused the degraded performance the LOS UAV telemetry. The internal factor is the drop of electrical voltage in the UAV, especially during the takeoff phase can cause the degraded performance of the LOS telemetry system. A decrease of 2.6% of voltage can degrade the performance of telemetry by -40 dBm. While the external factor is the presence of a cellular Base Station along the flight path of the UAV can cause the link loss phenomenon that can render the UAV LOS telemetry unusable. In this flight test, the UAV flies at an altitude of 300 m above sea level and still interferes with the cellular Base Station.