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基于Hilbert的单边带调制随机共振的微弱信号检测 被引量:14
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作者 张刚 吴瑕 《电子测量与仪器学报》 CSCD 北大核心 2019年第2期10-17,共8页
为了克服经典随机共振中的小参数检测条件的限制,介绍了基于Hilbert变换的单边带频率调制技术,并与二阶随机共振系统相结合,提出了运用调制随机共振的方法实现工程中大信号检测的应用。针对小采样频率和大采样频率进行了分开讨论,并对... 为了克服经典随机共振中的小参数检测条件的限制,介绍了基于Hilbert变换的单边带频率调制技术,并与二阶随机共振系统相结合,提出了运用调制随机共振的方法实现工程中大信号检测的应用。针对小采样频率和大采样频率进行了分开讨论,并对基频信号的选取做了相关研究。研究结果发现,小采样频率下,Hilbert单边带频率调制技术结合二阶系统有很好的检测效果。大采样频率下,可以结合变尺度处理进行优化。数值仿真分析表明,基频信号取在频率轴分辨率的10~60倍时,会有一个较高的并且较稳定的输出信噪比。并将变尺度Hilbert单边带频率调制技术运用于实际的轴承内外圈故障信号检测中,能明显、准确的检测出单频故障大信号。 展开更多
关键词 HILBERT变换 单边带调制 变尺度 二阶随机共振 大信号检测 轴承故障检测
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反辐射武器抗诱饵技术 被引量:14
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作者 梁永生 刘俊 朱全江 《电子信息对抗技术》 2017年第3期36-41,共6页
针对雷达诱饵面临的核心抗干扰问题,首先简述诱饵工作原理和特征,然后重点论述了反辐射武器抗诱饵技术,包括前沿跟踪、大信号检测、超分辨测向技术,最后简要概述了多模复合抗诱饵技术,包括被动/红外复合、被动/毫米波复合、被动/辐射计... 针对雷达诱饵面临的核心抗干扰问题,首先简述诱饵工作原理和特征,然后重点论述了反辐射武器抗诱饵技术,包括前沿跟踪、大信号检测、超分辨测向技术,最后简要概述了多模复合抗诱饵技术,包括被动/红外复合、被动/毫米波复合、被动/辐射计复合技术。指出了每一种抗诱饵技术的应用条件和局限性。为有效提高反辐射武器抗诱饵能力的适应性和可靠性,必须根据不同雷达和诱饵特性进行相应的对抗策略研究,综合采用多种技术手段。 展开更多
关键词 反辐射 抗诱饵 大信号检测 前沿跟踪 波达方向 谱估计
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AN EFFICIENT APPROXIMATE MAXIMUM LIKELIHOOD SIGNAL DETECTION FOR MIMO SYSTEMS
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作者 Cao Xuehong 《Journal of Electronics(China)》 2007年第1期23-26,共4页
This paper proposes an efficient approximate Maximum Likelihood (ML) detection method for Multiple-Input Multiple-Output (MIMO) systems,which searches local area instead of exhaustive search and selects valid search p... This paper proposes an efficient approximate Maximum Likelihood (ML) detection method for Multiple-Input Multiple-Output (MIMO) systems,which searches local area instead of exhaustive search and selects valid search points in each transmit antenna signal constellation instead of all hy-perplane. Both of the selection and search complexity can be reduced significantly. The method per-forms the tradeoff between computational complexity and system performance by adjusting the neighborhood size to select the valid search points. Simulation results show that the performance is comparable to that of the ML detection while the complexity is only as the small fraction of ML. 展开更多
关键词 Signal detection Maximum Likelihood (ML) Multiple-Input Multiple-Output (MIMO) system
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Digital Lock-in Amplifier Based on Microcontroller
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作者 陶安利 徐国栋 +1 位作者 骆科学 张钢领 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期285-288,共4页
A method of implementing high cost-effective and highly integrated digital lock-in amplifier with microcontroller is discussed. And the digital lock-in amplifier is more suitable for meastwing lowfrequency weak signal... A method of implementing high cost-effective and highly integrated digital lock-in amplifier with microcontroller is discussed. And the digital lock-in amplifier is more suitable for meastwing lowfrequency weak signal. Digital signal sequence is obtained through sampling signal measured over an integer number of signal periods, but digital reference sequence is acquired through mathematical operation, then digital phase sensitive detection can be implemented by calculating the cross-correlation function of digital signal sequence and digital reference sequence. In addition, the frequency response and phase character of the digital lock-in amplifier is analyzed. Finally, the designed digital lock-in amplifier is achieved. Expermental results show that the digital lock-in amplifier can be used for measuring weak signal with low ignal-to-noise ratio. 展开更多
关键词 digital lock-in amplifier SNR MICROCONTROLLER
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Magnetic particles and cadmium sulfide nanoparticles tagging for signal-amplifying detection of nucleic acids 被引量:4
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作者 DONG XiaoYa, ZHAO WeiWei, XU JingJuan & CHEN HongYuan State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China 《Science China Chemistry》 SCIE EI CAS 2011年第8期1304-1310,共7页
A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magne... A versatile DNA recognition system using cadmium sulfide nanoparticles (CdS NPs) as labels was proposed for ultrasensitive detection of specific sequence DNA based on target recycling. This strategy utilized the magnetic particles (MNPs) for the immobilization of linker DNA and CdS NPs and the subsequent target DNA hybridization. Using the unique characteristic of nicking endonuclease for cutting one specific strand of double strand DNA (ds DNA), the linker DNA could be transected and the target DNA could be liberated for re-hybridization and hence the amount of released CdS NPs was enhanced. Due to the advantage of the MNPs and signal amplification from the target recycling, the analyte DNA could be detected by the square-wave stripping voltammetry (SWV) in a wide linear range from 0.4 fM to 100 fM with the detection limit down to 0.08 fM. The proposed DNA detection strategy possesses high sensitivity, satisfactory reproducibility and excellent stability, which might have potential in other DNA biological assays. 展开更多
关键词 CdS nanoparticles square wave stripping voltammetry nicking endonuclease electrochemical DNA assay
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