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Frequency agile technology provides full play to the advantage of radars for adopting electronic countermeasures actively, which can effectively enhance the antinoise suppression jamming performance of radars. However, with the increasing complexity of the interference environment, developing an online decision-making method for frequency-agile radar with dynamic adaptability and without foresight of the nature of the environment is a demanding task. According to the features of the jamming strategy, suppression jamming scenarios are divided into three categories, and an online decision-making method for frequency-agile radar based on Multi-Armed Bandit (MAB) is developed to maximize the radar’s detection probability. This approach is an online learning algorithm that does not need to interfere with the foresight of the environment and offline training process and realizes remarkable learning performance from noninterference scenarios to adaptive interference scenarios. The simulation results and theoretical analysis demonstrate that compared with the classical algorithm and stochastic agile strategy, the proposed method has stronger flexibility and can effectively improve the antijamming and target detection performances of the frequency-agile radar for various jamming scenarios.

This is a paper in the field of mineral synthesis, covering the areas of mineral processing engineering and ceramics and composites. Tailings of a vanadium-titanium magnetite plant in Panzhihua were subjected to regrinding and re-election experiments, and an iron ore concentrate with a Fe grade of 58.59% was obtained by the "step grinding and step separation" process. The ilmenite concentrate with TiO2 grade of 46.63% was obtained by adopting the flotation flowsheet of "one roughing, one scavenging, three cleaning". The TFe and TiO2 of the reselection tailings of vanadium-titanium magnetite were 5.71% and 2.96%, respectively. The process was achieved efficient separation of effective components. The foamed ceramic material with a volume density of 482 kg/m3 and a water absorption rate of 2.35%, and a compressive strength of 3.03 MPa was obtained by using the reselection tailings of vanadium-titanium magnetite, feldspar tailings and kaolinite pyrite tailings as the base material, and silicon carbide as blowing agent at 1160℃ for 30 min. The comprehensive utilization of vanadium-titanium magnetite tailings is realized.