Prof. Tao YU
Chinese Aeronautical Radio Electronics Research Institute, China
Title: Breaking Wavelength Dependence: A New Paradigm for Broadband Doppler Direction Finding Without Frequency Priori
Abstract:
Traditional Doppler direction-finding methods are deeply coupled with signal wavelengths, which greatly limits their application scenarios. This paper proposes a broadband direction-finding method that requires no prior frequency information, with its core lying in the construction of a dual mapping mechanism: on one hand, it establishes a direct correlation between Doppler frequency shift and path difference in geometric space through radial velocity differential approximation; on the other hand, it extracts the motion velocity per unit wavelength based on second-order Doppler analysis, thereby realizing the analytical decoupling of wavelength in the direction-finding equation and completely eliminating the dependence on prior information of signal frequency or wavelength.
Monte Carlo simulation results show that the proposed mean-corrected three-point Doppler estimation algorithm can still control the direction-finding root mean square error (RMSE) below 0.05° even under large incident angle scenarios, which represents an accuracy improvement of nearly two orders of magnitude compared with the traditional two-point method. This method only requires the use of a simple equidistant linear array, without the need to meet the half-wavelength spacing constraint, complex phase calibration, or being limited to specific frequency bands. It can operate seamlessly across the entire frequency spectrum from High Frequency (HF) to Terahertz (THz) while maintaining the unity of model structure and parameters.
By shifting the direction-finding paradigm from "observation-driven" to "mapping-driven", this study constructs a new foundational architecture for passive direction-finding technology, and demonstrates broad application prospects in military reconnaissance, aviation navigation, electronic warfare, as well as cross-domain sensing fields such as acoustic sensing and quantum measurement.
Biography:
Professor Yu Tao, a leading academic figure in the field of passive detection and localization technology in China, was honored with the "Asia Lifetime Achievement Award" by Asian Figures in 2025. With decades of dedicated research in this domain, he pioneered several core theories, including the two-dimensional planar bistatic localization model, the ambiguity-free phase difference localization method, and the Doppler-based ranging fusion algorithm. These innovations have effectively broken through key bottlenecks in passive localization technology and have laid the foundation for a critical technical system supporting national strategic security. Professor Yu has published over 200 research papers, authored two academic monographs, and filed more than 20 invention patents. In 2024, he was awarded five gold medals at international invention exhibitions for four core research achievements. Consistently committed to aligning scientific advancements with national needs, he is a key contributor to the development of Asia’s core scientific and technological competitiveness.