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本文首先推导得到大信噪比条件下单脉冲比的近似公式;然后根据和、差通道噪声特性求得单脉冲比的统计特性;最后利用极大似然估计原理推导单脉冲公式,同时得出了信噪比的极大似然估计.研究建立了单脉冲与极大似然估计的理论联系.该研究不仅有利于“雷达原理”课程教学,同时对雷达工程实践也有参考价值. 相似文献
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本文介绍了一种在LabVIEW环境下通过LabVIEW MathScript调用MATLAB中小波函数实现对信号奇异点检测的方法。通过对传感器故障信号的仿真实验,较准确的定位到了突变点,同时给出了对应的消除措施,降低了检测信号的误差率,证明了该方法的有效性。 相似文献
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提出利用信号构造行数为2的矩阵,在奇异值分解后保留小奇异值对应的分量,并取大奇异值所对应的分量信号重复构造相同矩阵进行奇异值分解,从而将原始信号分解为一组分量信号.这种分量信号具有二阶消失矩,可实现对原始信号中Lipschitz指数为0和1的奇异性的位置精确检测,其检测脉宽小,且在同一层分量中指示奇异点位置的模极大值和奇异点处的突变量、转折斜率具有正比线性关系.此法克服了小波变换检测结果的位置偏移和脉冲宽大的缺陷,在对铣削力信号的处理中,准确地检测出了其中的微弱冲击. 相似文献
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小波分析在信号奇异性检测中的应用 总被引:10,自引:0,他引:10
研究了信号的奇异性检测问题。给出小波变换和信号奇异性的关系,实现小波分析对信号各类奇异间断点的有效检测,利用小波分析构造故障诊断所需的特征因子(或直接提取对诊断有用的信息),从而将该方法推广到各类冲击响应信号的奇异性检测中。最后给出一个实例进行验证。 相似文献
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《IEEE transactions on information theory / Professional Technical Group on Information Theory》1969,15(2):266-272
If a mathematical model of a signal detection problem is such that there exists a detector which achieves zero error, the model is called singular. Such models are usually not acceptable. In this paper, various sufficient conditions for singular detection and estimation are presented. For the case of a known signal, second-moment conditions are given which imply singularity of detection in the most general kind of noise. For the case of random signals, no such general result exists. Let the signal be a known function of some random parameters(t; gamma(omega)) and let the detection problem corresponding to each value ofgamma(omega) be singular. It is shown that ifgamma(omega) has a discrete distribution or if the noisen(t) is Gaussian, then detection is singular. Finally, ifn(t) is wide-sense stationary, if the signal is the sum of randomly spaced Fourier transformable signals, and if certain moment conditions are satisfied, then one can not only singularly detect the signal, but can also singularly estimate the unknown parameters of the signal--at least whenn(t) is Gaussian. 相似文献
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目标雷达散射截面(RCS),在复平面可以表示为复频域的函数。根据奇点(SEM)展开(留数)方法,计算对目标物体的散射奇点(留数),进行射频识别(RFID),是射频识别的新思路。通过FEKO软件,对蝶形无芯标签结构进行仿真得出该结构散射场。仿真的结果显示该结构具有开槽数量多、极点分布规律、数据容量大、易于实现等优点。 相似文献
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Ricardo Riaza Stephen L. Campbell Wieslaw Marszalek 《Circuits, Systems, and Signal Processing》2000,19(2):131-157
Some qualitative properties of singular equilibria arising in semiexplicit index-1 differential-algebraic equations are discussed in this paper. We extend a taxonomy of singularities from index-0 problems to address situations not covered by the singularity induced bifurcation, singular flow, and associated theorems. Although some related phenomena may occur, different behavior can be expected when the assumptions supporting these results are not satisfied, as is illustrated by several examples. Special attention is paid to the effect that the singular nature of the underlying ordinary differential equation and, eventually, of the solution manifold, has on the behavior of the original singular index-1 problem.Supported by a graduate fellowship from Universidad Politécnica de Madrid. The work of this author was done while he was with the Department of Mathematics at North Carolina State University.Research supported in part by NSF Grants DMS-9714811 and DMS-9802259. 相似文献