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33rd IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Gulum, T. O. Pace, P. E. Cristi, R. Naval Postgrad Sch Dept Elect & Comp Engn Monterey CA 93943 USA

ISBN: (纸本)9781424414833

Often used in low probability of intercept continuous waveform (CW) emitters, polyphase modulations can have extremely long code lengths (large processing gain), good sidelobe performance and robust Doppler tolerance. This paper presents an efficient algorithm to autonomously extract the polyphase radar modulation parameters from an intercepted waveform. using a Wigner-Ville Radon transform. Results show that our method results in a small relative error in the extracted parameters for signal-to-noise ratios as low as 6 dB.

关键词： Wigner-Ville distribution modulation parameters Radon transform

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Selection of diversity and modulation parameters for Nakagami fading channels to jointly satisfy outage and bit error requirements

Selection of diversity and modulation parameters for Nakagam...

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IEEE Wireless Communications and Networking Conference

作者： Sharma, P SUNY Buffalo Dept Comp Sci & Engn Buffalo NY USA

ISBN: (纸本)0780389662

Outage is an event of instantaneous signal-to-noise ratio OR bit error rate failing in an unacceptable operational regime. Outage performance analysis is traditionally carried out for diverse channel behaviors and transmission techniques, leaving the identification of unacceptable operational regime to user specified performance requirements. An alternative approach is taken in this work and an acceptable combination of system parameters are identified such that the user specified quality of service (QoS) constraints are satisfied. The QoS constraints are specified jointly in terms of outage probability, outage duration and probability of occurrence of errors during the outage event. This work presents inter-dependencies between the QoS constraints and modulation, diversity and signal parameters in closed form. The analysis assumes identically, independently distributed Nakagami interferers using maximal ratio diversity combining (MRC).

关键词： diversity reception error statistics fading channels modulation probability quality of service Nakagami fading channels QoS constraints bit error rate maximal ratio diversity combining modulation parameters outage duration outage probability quality of s

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Study on the influence of internal modulation parameters on the temperature calculation performance of matrix-searching CCD pyrometer

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MEASUREMENT SCIENCE AND TECHNOLOGY 2024年第3期35卷 036002-036002页

作者： Li, Chao Xu, Chundong Wang, Yongjuan Gao, Liming Zhang, Xiangyong Zhang, Qi Kong, Deren Nanjing Univ Sci & Technol Sch Mech Engn Nanjing 210094 Peoples R China Norinco Grp Test & Measuring Acad Technol Ctr Xian 710116 Peoples R China

Matrix-searching CCD temperature measurement technology can integrate the complex signal modulation process of CCD because of its forward solution of inverse problem. But in the existing research, there is still a lack of discussion on the temperature calculation ability of this technology in the internal modulation process. Therefore, the research on the influence of temperature calculation performance of matrix-searching CCD pyrometer is carried out. Based on the three-channel temperature equation and the radiation acquisition theory of the detector, the evaluation model of effective measurement range and temperature resolution is defined and constructed. Combined with the calibration experiment, the effects of gain and gamma internal modulation parameters on the effective temperature measurement range and temperature resolution are discussed. Through the analysis of the simulation results, the use and effects of the two internal modulation parameters are obtained, which not only improves the theoretical system of the matrix-seeking temperature measurement method, but also provides theoretical guidance for the parameter selection of the method under different conditions.

关键词： CCD pyrometer matrix-searching modulation parameters temperature measurement range

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Effect of Inverter modulation parameters on Mechanical-electric Coupling Vibration of an Ultra-High Speed Grinding System Driven by a Motorized Spindle

Effect of Inverter Modulation Parameters on Mechanical-elect...

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2007国际机械工程与力学会议

作者： Lang Lü Wanli XIONG Hongwu HUANG Hang GAO National Engineering Research Center for High Efficiency Grinding Hunan University

In order to improve the stability of a grinding system and suppress the mechanical-electric coupling vibration caused by a high-frequency converting current device, the effect of modulation parameters of an inverter on the mechanical-electric coupling vibration of an ultra-high speed grinding system driven by a motorized spindle is necessary to be studied. On the basis of a mechanical model of a grinding wheel rotor system, a mechanical-electric coupling model constituted by an inverter, a motorized spindle, a grinding wheel and grinding loads is established. Numerical methods are used to study physical mechanism of mechanical-electric coupling vibrations in some typical non-stationary processes, such as the starting, the speed rising and the grinding force importing. In numerical simulations, the physical mechanism of mechanical-electric coupling vibrations in two different modes of power supply, including an ideal sinusoidal voltage-source and a voltage-source inverter is studied comparatively. The physical mechanism of the mechanical-electric coupling vibration caused by high-order harmonic currents is revealed and its varying principle with inverter modulation parameters is given. Besides, an effective suppression method of the mechanical-electric coupling vibration induced by high-order harmonic currents is proposed.

关键词： Ultra-high speed grinding Motorized spindle Inverter modulation parameters Mechanical-electric coupling Vibration

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Experimental method based on wavelength-modulation spectroscopy for the characterization of semiconductor lasers under direct modulation

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APPLIED OPTICS 2004年第22期43卷 4446-4453页

作者： Schilt, S Thévenaz, L Ecole Polytech Fed Lausanne Swiss Fed Inst Technol Lab Nanophoton & Metrol CH-1015 Lausanne Switzerland

An experimental method is presented for characterization of the combined intensity and frequency modulation produced when the injection current of a laser diode is modulated. The reported technique is based on the analysis of the harmonic signals produced when a modulated laser is used to probe a gas absorption line by the so-called wavelength-modulation spectroscopy method. Based on a theoretical model of this technique, we present two methods that facilitate the determination of (i) the deviation in laser frequency and (ii) the phase shift between intensity and frequency modulation. These methods are illustrated experimentally by measurement of the modulation parameters of a 2-mum distributed-feedback laser by use of a CO2 absorption line. The experimental results have been compared with those obtained with another traditional method and have shown full agreement in the frequency range (400 Hz-30 kHz) considered. (C) 2004 Optical Society of America.

关键词： .deviation phase shift lock-in harmonic signals frequency modulation semiconductor lasers laser diodes theoretical model modulation frequency laser frequency distributed-feedback WMS Experimental method wavelength-modulation spectroscopy modulated laser modulation parameters

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Suppression of Self-Noise and Environmental Disturbances by Fusion in Fiber-Optic Gyroscopes for Precision Measurement

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IEEE SENSORS JOURNAL 2023年第13期23卷 14084-14094页

作者： Chen, Yanjun Zhu, Lanxin Cao, Yuwen Wang, Wenbo Huang, Huimin He, Yan Ma, Xiangdong Li, Zhengbin Peking Univ Sch Elect State Key Lab Adv Opt Commun Syst & Networks Beijing 100871 Peoples R China Peking Univ Sch Elect Engn & Comp Sci Beijing 100871 Peoples R China

We present a study of noise suppression by fusion in fiber-optic gyroscopes based on the source-sharing architecture. A theoretical model is proposed for the detailed analysis of the noise mechanism. The importance of the modulation parameters is revealed, and the optimal modulation strategies are given. Through simulations and experiments, we demonstrate that the proposed fusion scheme not only suppresses self-noise including relative intensity noise (RIN) and thermal phase noise (TPN), but also achieves complete elimination of environmental disturbances. Up to 5.8-fold suppression of self-noise and 5.2-fold reduction of bias instability (BI) is obtained in the experimental apparatus when compared with the performance before fusion. In the applications of fiber-optic gyroscopes for precision measurement, the proposed schemes effectively suppress the noises at the system level.

关键词： Gyroscopes Optical fiber sensors Optical variables measurement Sagnac interferometers Optical modulation Optical interferometry Optical fiber couplers Fiber-optic gyroscopes fusion configuration modulation parameters noise suppression

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Method of Four-Element Retrodirective Cross-Eye Jamming Based on DoA

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IEEE ACCESS 2020年 8卷 76896-76902页

作者： Liu, Wei Meng, Jin Zhou, Liang Naval Univ Engn Natl Key Lab Sci & Technol Vessel Integrated Powe Wuhan 430033 Peoples R China

The cross-eye method is commonly used to interfere monopulse radars. To overcome the strict tolerance and the range limitation of the traditional retrodirective cross-eye method and the multi-loop method, a novel four-element retrodirective cross-eye based on Direction of Arrival (DoA) is proposed. The mathematical model of the four-element retrodirective cross-eye jamming is derived based on the method of expansibility analysis, and the general formulas of indication angle are obtained. Based on the DoA information, the antenna layout of jamming loops is optimized, and the influence of the modulation parameters on cross-eye jamming effect are analyzed. The orthogonal four-element retrodirective cross-eye is compared with the traditional cross eye jamming, the results show that the the proposed method is superior to the traditional and the orthogonal four-element retrodirective cross-eye in terms of the jamming effect and the modulation parameter tolerance.

关键词： Cross-eye monopulse radar direction of Arrival (DoA) modulation parameters

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Research on digital forensics method of 5G communication system in the future based on direct intermediate frequency sampling

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INTERNATIONAL JOURNAL OF AUTONOMOUS AND ADAPTIVE COMMUNICATIONS SYSTEMS 2022年第1期15卷 46-62页

作者： Luo, Xian Liao, Rongtao Hu, Huanjun Ye, Yuxuan Informat & Commun Branch Hubei EPC Wuhan 430074 Peoples R China

To overcome the problems of low efficiency and poor security in the process of digital forensics, a digital forensics method based on direct if sampling for 5G communication system is proposed. In this method, the modulation parameters of the communication signal are obtained by the feature extraction algorithm of the receiver's in pulse signal, and the ontology model of digital forensics is constructed based on the ontology theory: analyse the disk image and judge the file category according to the pattern feature recognition results of the radiation source signal in 5g communication system;determine the hash value and information entropy, and generate the key index;summarise the digital forensics results and generate the digital forensics report. The simulation results show that the data processing efficiency is over 25/Mbps, and the successful attack rate in the security performance test is 2.89%.

关键词： intermediate frequency sampling 5G communication system digital forensics intra pulse feature mobile terminal encryption algorithm modulation parameters the ontology model

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Optimal design of the inlet temperature based periodic operation of non-isothermal CSTR using nonlinear output frequency response functions

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IFAC-PapersOnLine 2018年第18期51卷 620-625页

作者： Shi, Hongyan Lang, Z.Q. Zhu, Yunpeng Yuan, Decheng Wang, Wei Department of Information Engineering Shenyang University of Chemical and Technology Shenyang110142 China Department of Automatic and Control and Systems Engineering University of Sheffield SheffieldS1 3JD United Kingdom Department of Control Science and Engineering Dalian University of Technology Dalian116024 China

The periodic operation of a non-isothermal continuous stirred tank reactor (CSTR) using inlet temperature modulation is investigated in this paper. The DC component of the CSTR output concentration is optimized by tuning the modulation parameters of the inlet temperature in order to achieve a maximum conversion using a Nonlinear Output Frequency Response Functions (NOFRFs) based approach. The results show that the new approach is fast and efficient in the analysis and design of the periodic operation of CSTR and can potentially be applied to conduct the optimal design of periodic operation of other chemical engineering processes. © 2018

关键词： Optimal systems Chemical analysis Frequency response Isotherms modulation Chemical engineering process Continuous stirred tank reactor Frequency domains modulation parameters Non linear output frequency response function Optimal design Output concentrations Periodic operation

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Emission characteristics of Cu in Dc voltage modulation applied glow discharge optical emission spectrometry

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ANALYTICAL SCIENCES 2006年第4期22卷 599-602页

作者： Park, H Wagatsuma, K Tohoku Univ Mat Res Inst Sendai Miyagi 9808577 Japan

In order to obtain the depth profile of a thin film, we investigated the emission characteristics of a voltage modulation glow discharge to optimize the modulation parameters (modulation voltage, offset voltage, and modulation frequency). In this study, a phase-sensitive detection method with a lock-in amplifier to the modulation technique led to a higher sensitivity and a larger signal-to-noise ratio in the emission analysis compared to the normal dc amplification method. Upon increasing the maximum voltage, the emission intensity of the Cu atomic line (CuI 239.34 nm) increased linearly at a modulation voltage of 400 V and an offset voltage of 300 V. On the other hand, the emission intensity was gradually reduced when a modulation frequency increased. It is advantageous for surface analysis that the voltage modulation technique gives a lower sputtering rate rather than the conventional dc discharge.

关键词： .emission intensity Phase-Sensitive GD-OES optical emission modulation frequency depth profile emission characteristics Dc Voltage modulation parameters modulation voltage offset voltage lock-in amplifier modulation technique maximum voltage conventional dc

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