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Recognition of Radar Emitter Signals Based on SVD and AF Main Ridge Slice
Qiang Guo,Pulong Nan,Xiaoyu Zhang,Yuning Zhao,Jian Wan 한국통신학회 2015 Journal of communications and networks Vol.17 No.5
Recognition of radar emitter signals is one of core elements in radar reconnaissance systems. A novel method based on singular value decomposition (SVD) and themain ridge slice of ambiguity function (AF) is presented for attaining a higher correct recognition rate of radar emitter signals in case of low signal-tonoise ratio. This method calculates the AF of the sorted signal and ascertains the main ridge slice envelope. To improve the recognition performance, SVD is employed to eliminate the influence of noise on the main ridge slice envelope. The rotation angle and symmetric Holder coefficients of the main ridge slice envelope are extracted as the elements of the feature vector. And kernel fuzzy cmeans clustering is adopted to analyze the feature vector and classify different types of radar signals. Simulation results indicate that the feature vector extracted by the proposed method has satisfactory aggregation within class, separability between classes, and stability. Compared to existing methods, the proposed feature recognition method can achieve a higher correct recognition rate.
Yu, Jianguo,Wei, Dan,Zheng, Zhe,Yu, Wenjie,Shen, Honghui,Qu, Yuning,Wen, Shuya,Kwon, Young-Uk,Zhao, Yongnan Elsevier 2020 JOURNAL OF COLLOID AND INTERFACE SCIENCE - Vol.566 No.-
<P><B>Abstract</B></P> <P>x%Pt-Naf-CV (Pt-Nafion-Cyclic Voltammetry) catalysts with homogeneously distributed platinum nanoparticles and ultra-low Pt loading are successfully synthesized by using a facile potential cycling approach. The as-synthesized 0.8%Pt-Naf-CV catalyst exhibits an enhanced electrocatalytic activity for hydrogen evolution reaction (HER) in 0.5 M H<SUB>2</SUB>SO<SUB>4</SUB> solution, which obtains a low overpotential of 34 mV at 10 mA cm<SUP>−2</SUP>. The linear sweep voltammetry (LSV) curve of 0.8%Pt-Naf-CV catalyst is almost consistent with that of commercial Pt/C. However, the 0.8%Pt-Naf-CV catalyst displays a more excellent stability and durability in comparison with commercial Pt/C. Besides, the Pt loading of Pt/C (Pt–10 wt%) is about 10 times that of 0.8%Pt-Naf-CV catalyst. The improved electrocatalytic performances are derived from the synergistic effects of Pt and Nafion. The Nafion plays a significant role as a dispersant, carrier and structure directing agent on the morphology and size of the Pt catalyst. This result contributes a promising method to enhance the catalytic activity and reduce the amount of Pt.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>