A Method for HF Skywave Source Geolocation in Unknown Ionosphere Environments and Experimental Results

Large-scale real-time ionospheric information is difficult to obtain promptly, plaguing the timely and accurate geolocation of high-frequency (HF) sources in unknown ionosphere environments. In this letter, we propose a novel HF skywave source geolocation method based on the time difference of arrival with semidefinite programming, and no priori information about the ionosphere is necessary. In the simulations, the proposed method is compared with existing methods and detailed geolocation error distribution maps are given. In the experiments, HF I/Q data captured from the same source at different times on different dates are used to validate the proposed method. Simulated and experimental results show that the proposed method improves the positioning accuracy by about 40% compared with existing methods under the same conditions, and the average relative positioning error is less than 1.8%.