LDACS-Based Wide Area Multilateration for Surveillance: An Iterative Reweighted Least Square Method Using TDOA and FDOA Measurements

The L-band Digital Aeronautical Communication System (LDACS) has been recognized by the International Civil Aviation Organization (ICAO) as the first integrated communication, navigation, and surveillance system designed for future air traffic management. In wide-area multipoint wireless positioning, recent studies have investigated various techniques, including those based on Time Difference of Arrival (TDOA). However, conventional methods are often limited by low estimation accuracy and slow convergence, mainly when applied to fast-moving targets such as aircraft. To address these challenges, this study proposes a hybrid TDOA and Frequency Difference of Arrival (FDOA) method designed to improve the accuracy of position and velocity estimation for aircraft using LDACS ground stations. To overcome the limitations of traditional methods, the proposed approach incorporates the Iterative Weighted Least Squares (IRLS) method, which refines the iterative process and improves the precision of the estimation. To validate the effectiveness of the technique, the Cramér-Rao Lower Bound (CRLB) is derived, and a series of simulation experiments are conducted to assess performance. The results demonstrate that the proposed method achieves high accuracy and computational efficiency, approaching CRLB performance, thus reinforcing the feasibility of LDACS for aircraft surveillance applications.