Project Abstract

Unmanned Aerial Vehicles (UAVs) operating under tree canopy are frequently exposed to unexpected and complicated obstacles, which leads to sudden deterioration of WiFi signal strength under Non-Line-of-Sight (NLOS) environment. The substantially reduced WiFi communication coverage under dense rainforest and farming situations causes temporary UAV control loss and creates critical damage to the UAV.

Hence, the adoption of Long Range (LoRa) is proposed as a secondary telemetry communication medium for the UAV navigation, where LoRa is an emerging Low Power Wide Area Networks (LPWAN) technology, optimised for Internet of Things (IoT) applications for its low power consumption and wide area coverage feature. With the aid of cognitive radio technology, our multi-mode communication module constituting WiFi, LTE, and two types of LoRa supporting 433 MHz and 900 MHz, will be optimised to achieve best possible coverage range.

A cognitive radio aided transceiver will be employed to enable intelligent detection of the best communication type and available empty channels in terms of a harmonised set of the Received Signal Strength Indicator (RSSI), Signal-to-Noise-Ratio (SNR), and coverage range. Additionally, by adopting a novel LoRa mesh network consisting of a mobile LoRa node and several LoRa nodes on the ground, further extension of UAV communication coverage will be investigated under the above-mentioned situations.