A robust Carrier Frequency and Timing Offset Estimation in Inter-UAV OFDM Communication Links

The UAV-mounted base station has been integrated into 5G and beyond to provide communication in an emergency when conventional systems fail due to some reason. Moreover, it is also used in coverage enhancement and for other strategic purposes. In this work, we have considered a MIMO-OFDM based UAV system that is inclined to fast-fading channels due to the continuous motion of UAVs. Due to the mobility of UAVs, there is a frequency and timing offset which must be estimated for proper and seamless communication. For that purpose, we have proposed a data-aided maximum likelihood-based scheme that efficiently estimates the carrier frequency and timing offset. Results show that our algorithm outperforms the state-of-the-art system in terms of MSE.