A High-Precision Direction Finding Method Assisted by Multipoint Ranging Sequences

The positioning accuracy of radio aviation search and rescue is composed of two parts: ranging error and direction finding error. Direction finding error is easily affected by complex environmental interference, leading to a rapid increase in positioning error. To solve this problem, this work proposes a novelly method of using multi-point ranging information to improve direction finding accuracy. Firstly, virtual target positions are generated using direction finding estimation information. Then, a set of ranging sequences is constructed, and direction finding information is estimated using multi-point ranging information and airborne position information in the set. Subsequently, a method using GDOP metric to update the set of ranging sequences is proposed, which significantly reduces the computational complexity and storage unit of the algorithm while ensuring its accuracy. Finally, simulation results show that the proposed method can achieve high-precision direction finding performance in complex environments.