UAV-based passive geolocation based on channel estimation

In this paper, we propose a Time Difference of Arrival (TDoA) algorithm for passive geolocation based on delay estimation of two correlated wireless channels. It's assumed that the passive receiver is carried by a small flying UAV in the sky, and the transmitter is located on the ground (static or mobile), so Rician flat fading model should be used. To estimate the delay of two correlated channels, Block Phase Estimation (BPE) is used for each wireless channel estimation, and then the two estimated channels are compared to get the best time delay. We also compare it against a cross-correlation-based TDoA algorithm. Simulation results show that our TDoA algorithm performs much better than the cross-correlation-based TDoA algorithm with a lower level of magnitude in terms of average TDoA error and Root-Mean-Square-Error (RMSE). Four different Rician fading channel groups are evaluated, and conclusions are drawn for our TDoA algorithm and the cross-correlation-based TDoA algorithm.