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基于NOA-VMD的炮口冲击波谐振噪声降噪算法
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作者 杨浩越 孟祥瑞 +1 位作者 鞠明池 王英志 《弹箭与制导学报》 北大核心 2024年第4期9-17,共9页
火炮发射时产生的炮口冲击波信号频谱范围广,受限于采集系统中压力传感器有效工作带宽导致采集过程引入大量谐振噪声。为了降低谐振噪声对炮口冲击波信号的影响,提出了一种基于星鸦优化算法(NOA)优化变分模态分解(VMD)的炮口冲击波谐振... 火炮发射时产生的炮口冲击波信号频谱范围广,受限于采集系统中压力传感器有效工作带宽导致采集过程引入大量谐振噪声。为了降低谐振噪声对炮口冲击波信号的影响,提出了一种基于星鸦优化算法(NOA)优化变分模态分解(VMD)的炮口冲击波谐振噪声降噪算法。首先以最小包络熵为适应度函数的NOA对VMD的分解模态数与惩罚因子参数进行优化;其次通过NOA-VMD算法对炮口冲击波信号进行分解,计算各分量谐振能量损失比筛选出谐振分量;最后对剩余信号分量进行重构得到去除谐振分量的炮口冲击波。实验结果表明,NOA寻优效果最佳,基于NOA-VMD算法有效降低谐振噪声对炮口冲击波信号的干扰。 展开更多
关键词 炮口冲击波 谐振噪声 星鸦优化算法 变分模态分解 谐振能量损失比
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电源与地平面间谐振电压噪声和阻抗特性仿真 被引量:2
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作者 高成 寇震梦 黄姣英 《安全与电磁兼容》 2020年第6期65-69,共5页
多层PCB板中的电源与地平面间的谐振效应会引发电压噪声及电磁辐射问题。利用Cadence Sigrity软件,从电源和地平面间谐振电压噪声和阻抗特性两个维度对谐振效应进行了评估。通过控制变量,对比不同PCB设计下的仿真结果,发现增加去耦电容... 多层PCB板中的电源与地平面间的谐振效应会引发电压噪声及电磁辐射问题。利用Cadence Sigrity软件,从电源和地平面间谐振电压噪声和阻抗特性两个维度对谐振效应进行了评估。通过控制变量,对比不同PCB设计下的仿真结果,发现增加去耦电容、减小平面间距和合理的平面分割方式可以降低谐振效应。 展开更多
关键词 电源和地平面 谐振电压噪声仿真 阻抗仿真 Cadence Sigrity软件 PCB设计
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905MHz低相噪声表面波振荡器的设计 被引量:1
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作者 刘春宁 费元春 《微波学报》 CSCD 北大核心 2002年第4期57-60,63,共5页
本文分析了声表面波谐振器的性能 ,论述了声表面波振荡器的工作原理及设计方法 ,最终完成中心频率为 90 5MHz的振荡电路 ,相位噪声低于 - 110dBc/Hz/ 1kHz。
关键词 声表面波 谐振 振荡器 相位噪声
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检波器数量对组合压噪能力的影响 被引量:6
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作者 魏继东 《物探与化探》 CAS CSCD 北大核心 2011年第2期238-242,247,共6页
根据组合压噪的有关理论,在其他因素不变的情况下,采用数量越多的检波器,组合压制干扰波的效果越好。这使得人们认为在施工中应该采用尽量多的检波器以提高资料的信噪比。但是通过分析组合中检波器数量对规则干扰波,随机干扰波以及耦合... 根据组合压噪的有关理论,在其他因素不变的情况下,采用数量越多的检波器,组合压制干扰波的效果越好。这使得人们认为在施工中应该采用尽量多的检波器以提高资料的信噪比。但是通过分析组合中检波器数量对规则干扰波,随机干扰波以及耦合高频微震衰减的影响证明:在其他因素不变的情况下,线性等灵敏度组合增加到"γm ax+3"个检波器以后(其中γm ax=组合基距/最小干扰波视波长),组合对于规则干扰波的衰减能力不再随着检波器数量的增加而显著提高。在组合基距确定的情况下,检波器数量越多,对随机干扰的衰减越明显(包括在组内距小于随机干扰相关半径的情况下);但是增加到一定数量后,衰减效果不再出现明显变化。检波器数量的多少对衰减耦合高频微震没有明显作用。同时指出,确定组合中合理的检波器数量要与组合的摆放形式相结合;组合图形不合理的情况下,增加检波器数量不会显著提高组合的压噪能力;灵敏度分布不合理,是导致组合压噪能力降低的重要原因。在线性等灵敏度组合的基础上,利用玫瑰图进行分析,可以确定工区面积组合(包括道间混波后)中使用的合理的检波器数量。 展开更多
关键词 检波器数量 压噪能力 相干噪声 环境噪声 内部噪声 耦合谐振噪声
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Novel Ka-band low-noise down-converter assembly 被引量:1
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作者 李鸣 李兴国 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期461-464,共4页
An efficient way to design a down-converter assembly for the Ka-band millimeter system is presented, in which dielectric resonators (DR's) are adopted in the Schottky barrier diode image recovery mixer and the loca... An efficient way to design a down-converter assembly for the Ka-band millimeter system is presented, in which dielectric resonators (DR's) are adopted in the Schottky barrier diode image recovery mixer and the local oscillator (LO). DR structures guarantee high frequency stability with an acceptable volume. The configurations of low noise amplifier, mixer and oscillator in the assembly are described and fabricated to estimate the chain performance. According to the verification results, the assembly exhibits the noise figure of less than 5 dB over 1 GHz frequency range, and the single-sideband phase noise (200 kHz offset from carrier frequency) of - 70 dBc/Hz. Utilizing the DR structure, the frequency stability of the local oscillator is less than 60 × 10^-6/℃. 展开更多
关键词 DOWN-CONVERTER dielectric resonator noise figure conversion loss
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Low phase noise LC VCO design in CMOS technology 被引量:2
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作者 李智群 王志功 +1 位作者 张立国 徐勇 《Journal of Southeast University(English Edition)》 EI CAS 2004年第1期6-9,共4页
This paper presents the design and the experimental measurements of two complementary metal-oxide-semiconductor (CMOS) LC-tuned voltage controlled oscillators (VCO) implemented in a 0.18 μm 6-metal-layer mixed-signal... This paper presents the design and the experimental measurements of two complementary metal-oxide-semiconductor (CMOS) LC-tuned voltage controlled oscillators (VCO) implemented in a 0.18 μm 6-metal-layer mixed-signal/RF CMOS technology. The design methodologies and approaches for the optimization of the ICs are presented. The first design is optimized for mixed-signal transistor, oscillated at 2.64 GHz with a phase noise of -93.5 dBc/Hz at 500 kHz offset. The second one optimized for RF transistor, using the same architecture, oscillated at 2.61 GHz with a phase noise of -95.8 dBc/Hz at 500 kHz offset. Under a 2 V supply, the power dissipation is 8 mW, and the maximum buffered output power for mixed-signal and RF transistor are -7 dBm and -5.4 dBm, respectively. Both kinds of oscillators make use of on-chip components only, allowing for simple and robust integration. 展开更多
关键词 CMOS integrated circuits Integrated circuit layout TRANSISTORS
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Noise-improved information transmission in a nonlinear threshold array for Gaussian mixture noise 被引量:1
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作者 王友国 吴乐南 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期31-34,共4页
To discuss further the dependence of stochastic resonance on signals, nonlinear systems and noise, especially on noise, the binary input signal buried in Gaussian mixture noise through a nonlinear threshold array is s... To discuss further the dependence of stochastic resonance on signals, nonlinear systems and noise, especially on noise, the binary input signal buried in Gaussian mixture noise through a nonlinear threshold array is studied based on mutual information. It is obtained that Gaussian mixture noise can improve the information transmission through the array. Both stochastic resonance (SR) and suprathreshold stochastic resonance (SSR) can be observed in the single threshold system and in the threshold array. The parameters in noise distribution affect the occurrence of SR and SSR. The efficacy of information transmission can be significantly enhanced as the number of threshold devices in the array increases. These results show further the dependence of SR and SSR on the noise distribution, and also extend the applicability of SR and SSR in information transmission. 展开更多
关键词 stochastic resonance suprathreshold stochastic resonance mutual information Gaussian mixture noise
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Entropy Correlations and Entanglement of a Superconducting Charge Qubit in a Resonant Cavity in the Presence of Noise 被引量:2
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作者 Hünkar Kayhan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第7期139-143,共5页
We study the dynamics of the entropy correlations and entanglement in a system of interaction of a superconducting charge qubit with a single-mode resonant cavity subject to noise considered as two-state random phase ... We study the dynamics of the entropy correlations and entanglement in a system of interaction of a superconducting charge qubit with a single-mode resonant cavity subject to noise considered as two-state random phase telegraph noise. We show that although the noise has an apparent suppressing effect on the evolution of the entropies of the qubit and the field and also on the entanglement in the system, the entropy exchange between the qubit and the field is independent of it during the time evolution of the system. 展开更多
关键词 random phase telegraph noise ENTROPY ENTANGLEMENT
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Stochastic Resonance Induced by Dichotomous Resistor in an Electric Circuit
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作者 LI Jing-Hui HAN Yin-Xia 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期487-490,共4页
Abstract An electric circuit with dichotomous resistor is investigated. It is shown that the amplitude of the average electric current washing the resistor represents the phenomenon of stochastic resonance, which is t... Abstract An electric circuit with dichotomous resistor is investigated. It is shown that the amplitude of the average electric current washing the resistor represents the phenomenon of stochastic resonance, which is the response as a function of the correlation time of the dichotomous resistor. 展开更多
关键词 stochastic resona.nce dichotomous noise electric current
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Mean First Passage Time for System with Fluctuating Potential Barrier and Coupled Noise
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作者 LI Jing-Hui HAN Yin-Xia 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3期517-519,共3页
In this paper we study the mean first passage time (MFPT) over a fluctuation potential barrier driven by a coupled noise. It is shown that the MFPT over the fluctuation potential barrier displays resonant activation... In this paper we study the mean first passage time (MFPT) over a fluctuation potential barrier driven by a coupled noise. It is shown that the MFPT over the fluctuation potential barrier displays resonant activations as the function of the flipping rate of the fluctuation potential barrier, and as the function of the dichotomous noise transition rate. 展开更多
关键词 mean fist passage time resonant activation coupled noise
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基于单端开路系统函数的介质振荡器的设计
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作者 宣伯乐 袁乃昌 张晓发 《电波科学学报》 EI CSCD 2004年第z1期156-158,共3页
介绍了X波段的介质谐振腔稳频的振荡电路的理论分析和数值仿真设计.振荡器由高介电常数的介质谐振腔形成的反馈回路和单端开路负阻振荡器构成.谐振腔的设计可以用一个简单的传输线型的模型进行仿真,使得理论分析得以试验的证实.电路的... 介绍了X波段的介质谐振腔稳频的振荡电路的理论分析和数值仿真设计.振荡器由高介电常数的介质谐振腔形成的反馈回路和单端开路负阻振荡器构成.谐振腔的设计可以用一个简单的传输线型的模型进行仿真,使得理论分析得以试验的证实.电路的仿真结果和测试结果吻合良好,其工作在10.576GHz,输出功率在16dBm,这种振荡器可以应用在很多微波系统. 展开更多
关键词 介质谐振 负阻振荡器 差损 相位噪声
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Response of harmonically and stochastically excited strongly nonlinear oscillators with delayed feedback bang-bang control 被引量:4
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作者 Chang-shui FENG Wei-qiu ZHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第1期54-61,共8页
We studied the response of harmonically and stochastically excited strongly nonlinear oscillators with delayed feedback bang-bang control using the stochastic averaging method. First, the time-delayed feedback bang-ba... We studied the response of harmonically and stochastically excited strongly nonlinear oscillators with delayed feedback bang-bang control using the stochastic averaging method. First, the time-delayed feedback bang-bang control force is expressed approximately in terms of the system state variables without time delay. Then the averaged It6 stochastic differential equations for the system are derived using the stochastic averaging method. Finally, the response of the system is obtained by solving the Fokker-Plank-Kolmogorov (FPK) equation associated with the averaged lt6 equations. A Duffing oscillator with time-delayed feedback bang-bang control under combined harmonic and white noise excitations is taken as an example to illus- trate the proposed method. The analytical results are confirmed by digital simulation. We found that the time delay in feedback bang-bang control will deteriorate the control effectiveness and cause bifurcation of stochastic jump of Duffing oscillator. 展开更多
关键词 Nonlinear system Delayed feedback bang-bang control Combined harmonic and white noise excitation Stochastic averaging Stationary response Stochastic jump
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