A.A. Mardiev1, V.D. Kuptsov2

1,2 Peter the Great St. Petersburg Polytechnic University (St. Petersburg, Russia)

1 mardiev.aa@edu.spbstu.ru; 2 kuptsov@spbstu.ru

Problem statement. Passive radio direction-finding systems usin g the time-difference-of-arrival (TDOA) method require solution s to improve accuracy and eliminate "blind spots" where small errors in TDOA measurements lead to significant errors in position or bearing determination. A promising approach to addressing these iss ues is adaptive baseline selection in direction-finding systems based on TDOA fusion. A key issue, understudied in the context of adaptive baseline selection, is the comprehensive consideration of the influence of the range-to-baseline ratio (R/d) and the angle of a rrival on the local accuracy of TDOA measurements and, conseque ntly, on the accuracy of direction-finding.

Objective. Develop a comprehensive methodology that identifies the most sensitive angular bearing baselines and quantifies the reliability of measurements on each a vailable baseline, taking into account the influence of SNR, bandwidth, the ratio of the dist ance from the source to the length of the baseline, and the angle of arrival.

Results. It was found that the root mean square error (RMSE) of the direction finding estimate using the proposed method, base d on adaptive selection of optimal baselines and weighted fusion of TDOA estimates, exceeds that of the non-adaptive method by more than 2-5 times. Furthermore, the proposed method allows for the virtual elimination of angular blind spots and ensures uniform accuracy across the entire angular range. Practical application. Optimal adaptive selection and weighted fusion of TDOA estimates can significantly improve the accuracy of direction finding, especially in conditions where the radio source is located at different distances and angles relative to the receiving antennas.

Mardiev A.A., Kuptsov V.D. Adaptive baseline selection based on the fusion of TDOA estimat es in direction finding systems. Radiotekhnika. 2026. V. 90. № 3. P. 90−106. DOI: https://doi.org/10.18127/j00338486-202603-08 (In Russian)

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