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Functional inputs to passive correlation detectors for oscillatory transient signals

IEEE JOURNAL OF OCEANIC ENGINEERING 1999年第1期24卷 67-80页

作者： Pflug, LA Ioup, GE Ioup, JW USN Res Lab Ocean Acoust Branch Stennis Space Ctr MS 39529 USA Univ New Orleans Dept Phys New Orleans LA 70148 USA

This research investigates whether passive detection of transient signals can be improved by replacing received signals with functionals of the received signals in correlation detectors, Specifically, this paper assesses the impact of using energy spectrum and autocorrelation functional inputs to the crosscorrelation (energy), bicorrelation, and tricorrelation detectors. Test signals with differing autocorrelation and energy spectrum properties are used in computer simulations with independent Gaussian noise to evaluate detector performance. Detection results are presented for the case when only two channels of input data are available to form the correlations, as well as the case when three and four channels of input data are available to form the higher order correlations. In the former case, it is shown that detection performance can be improved for the narrow-band signals by using the energy spectrum and autocorrelation functional inputs rather than the original received signal. In the latter case, it is shown that detection performance can be improved by using the autocorrelation input for the broadband signal and the energy spectrum input for the narrow-band signals, and that the tricorrelation detector performs best for the signals tested.

关键词： correlation detectors detection higher order statistics passive detectors transients

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Analysis of correlation and FACCD detectors in the strong-signal region

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Telecommunications and Radio Engineering (English translation of Elektrosvyaz and Radiotekhnika) 1995年第8期49卷 26-32页

作者： Tuzlukov, V.P.

This paper makes a comparative analysis of the results of an experimental investigation of two types of detectors for a signal-to-interference voltage ratio of 7.96 dB at the input;the signal detection attributes of s... 详细信息

关键词： correlation detectors

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detectors correlation factor of broadband measurements used in automotive EMC

Detectors correlation factor of broadband measurements used ...

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IEEE Symposium on Electromagnetic Compatibility

作者： Rakouth, Heritianarisoa Hozeska, Robert Cammin, Clane Delphi Automot Syst Saginaw Steering Syst Saginaw MI 48601 USA

ISBN: (纸本)9781424402939

Current CISPR12 broadband test limits are based on a 20 dB correlation factor between peak and quasi-peak measurements at 120 kHz bandwidth. This value is based on the experimental data accumulated in several countries. Electricthybrid vehicle power handling technologies produce new types of impulsive noise that call for a review of the current correlation factor. This document provides analytical insight on the empirical 20 dB correlation factor. Recommendations accounting for the new power technologies are given at the end of the paper.

关键词： correlation detectors

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Measuring photon correlation using imperfect detectors

arXiv

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arXiv 2024年

作者： Clark, Rachel N. Bishop, Sam G. Cannon, Joseph K. Hadden, John P. Dolan, Philip R. Sinclair, Alastair G. Bennett, Anthony J. School of Engineering Cardiff University Queen’s Building The Parade CardiffCF24 3AA United Kingdom Translational Research Hub Maindy Road CardiffCF24 4HQ United Kingdom National Physical Laboratory Hampton Road TeddingtonTW11 0LW United Kingdom

Single-photon detectors are "blind" after the detection of a photon, and thereafter display a characteristic recovery in efficiency, during which the number of undetected photons depends on the statistics of the incident light. We show how the efficiency-recovery, photon statistics and intensity have an interdependent relationship which suppresses a detector’s ability to count photons and measure correlations. We also demonstrate this effect with an experiment using n such detectors to determine the nth order correlation function with pseudothermal light. © 2024, CC BY.

关键词： correlation detectors

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Influence of laser pulse on the autocorrelation function of H in a strong electric field

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Chinese Optics Letters 2009年第1期7卷 1-4页

作者：王立飞杨光参 School of Physics and Electronic Information Wenzhou University

The autocorrelation function of electronic wave packet of hydrogen atom in a strong electric field below the zero-field ionization threshold is investigated in the formalism of semiclassical theory. It is found that the autocorrelation depends on the applied laser pulse significantly. In the case of narrow laser pulse, the reviving peaks in the autocorrelation can be attributed to the closed orbits of electrons, which are related to the classical dynamics of the system. But this correspondence is wiped out with increasing the laser width because of the interference among the adjacent reviving peaks.

关键词： correlation detectors Electric field effects Electric fields Hydrogen Laser beams Laser pulses Lasers Photolithography Probability density function Programming theory Regression analysis

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Signal detection and classification based on the estimation-correlation statistic

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JOURNAL OF COMMUNICATIONS TECHNOLOGY AND ELECTRONICS 2002年第3期47卷 290-299页

作者： Sosulin, YG Kostrov, VV

Optimal and quasi-optimal estimation-correlation algorithms intended for the multialternative detection (recognition) of stochastic signals in the presence of white noise are synthesized. The estimation-correlation algorithms are shown to be sufficiently general and valid for discrete-time observations in noise described by Gaussian and non-Gaussian statistics. Properties of the algorithms synthesized and the estimates they use are discussed. Performance of the estimation-correlation algorithms designed for discriminating correlated Gaussian signals and detecting a random telegraph signal is analyzed. A sign estimation-correlation detector is proposed and analyzed. The problem of classifying signals of the first and second scan strokes, which occurs in pulsed range-ambiguity radars, is considered.

关键词： Valid Telegraphies signal acquisition white noise algorithms Gauss signals radar discrete-time correlation detectors Optimal

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SPECTRA FOR THE PRODUCT OF GAUSSIAN NOISES

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METROLOGY AND MEASUREMENT SYSTEMS 2012年第4期19卷 653-658页

作者： Kish, Laszlo Bela Mingesz, Robert Gingl, Zoltan Granqvist, Claes-Goran Texas A&M Univ Dept Elect & Comp Engn College Stn TX 77843 USA Univ Szeged Dept Tech Informat H-6701 Szeged Hungary Uppsala Univ Dept Engn Sci Angstrom Lab SE-75121 Uppsala Sweden

Products of Gaussian noises often emerge as the result of non-linear detection techniques or as parasitic effects, and their proper handling is important in many practical applications, including fluctuation-enhanced sensing, indoor air or environmental quality monitoring, etc. We use Rice's random phase oscillator formalism to calculate the power density spectra variance for the product of two Gaussian band-limited white noises with zero-mean and the same bandwidth W. The ensuing noise spectrum is found to decrease linearly from zero frequency to 2W, and it is zero for frequencies greater than 2W. Analogous calculations performed for the square of a single Gaussian noise confirm earlier results. The spectrum at non-zero frequencies, and the variance of the square of a noise, is amplified by a factor two as a consequence of correlation effects between frequency products. Our analytic results are corroborated by computer simulations.

关键词： fluctuation-enhanced sensing correlation detectors indoor and environmental air quality sensing

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Inferring Aftershock Sequence Properties and Tectonic Structure Using Empirical Signal detectors

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PURE AND APPLIED GEOPHYSICS 2015年第2期172卷 359-373页

作者： Junek, William N. Kvaerna, Tormod Pirli, Myrto Schweitzer, Johannes Harris, David B. Dodge, Douglas A. Woods, Mark T. Patrick AF Base AF Tech Applicat Ctr Brevard FL USA NORSAR Kjeller Norway Deschutes Signal Proc Maupin OR USA Lawrence Livermore Natl Lab Livermore CA USA

Seismotectonic studies of the 2008 Storfjorden aftershock sequence were limited to data acquired by the permanent, but sparse, regional seismic network in the Svalbard archipelago. Storfjorden's remote location and harsh polar environment inhibited deployment of temporary seismometers that would have improved observations of sequence events. The lack of good station coverage prevented the detection and computation of hypocenter locations of many low magnitude events (mb < 2.5) in the NORSAR analyst-reviewed bulletin. As a result, the fine structure of the sequence's space-time distribution was not captured. In this study, an autonomous event detection and clustering framework is employed to build a more complete catalog of Storfjorden events using data from the Spitsbergen (SPITS) array. The new catalog allows the spatiotemporal distribution of seismicity within the fjord to be studied in greater detail. Information regarding the location of active event clusters provides a means of inferring the tectonic structure within the fault zone. The distribution of active clusters and moment tensor solutions for the Storfjorden sequence suggests there are at least two different structures within the fjord: a NE-SW trending linear feature with oblique-normal to strike-slip faulting and E-W trending normal faults.

关键词： correlation detectors Subspace detectors Aftershock sequence Tectonics Seismicity

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A Waveform Detector That Targets Template-Decorrelated Signals and Achieves Its Predicted Performance, Part I: Demonstration with IMS Data

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BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA 2016年第5期106卷 1998-2012页

作者： Carmichael, Joshua D. Los Alamos Natl Lab Bikini Atoll RdSM 30 Los Alamos NM 87544 USA

Waveform correlation detectors used in seismic monitoring scan multi-channel data to test two competing hypotheses: that the data contain (1) a noisy, amplitude-scaled version of a template waveform or (2) only noise. In reality, seismic wavefields include signals triggered by nontarget sources (background seismicity) and target signals that are only partially correlated with the waveform template. We reform the waveform correlation detector hypothesis test to accommodate deterministic uncertainty in template-to-target waveform similarity and thereby derive a new detector from convex set projections (the cone detector) for use in explosion monitoring. Our analyses give probability density functions that quantify the detectors' degraded performance with decreasing waveform similarity. We then apply our results to three announced North Korean nuclear tests and use International Monitoring System (IMS) arrays to determine the probability that low magnitude, off-site explosions can be reliably detected with a given waveform template. We demonstrate that cone detectors provide (1) an improved predictive capability over correlation detectors to identify such spatially separated explosive sources, (2) competitive detection rates, and (3) reduced false alarms on background seismicity.

关键词： waveforms signals correlation detectors North Korean

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On the interpretation of the layered structures detected by mesosphere-stratosphere-troposphere radars in dual frequency domain interferometry mode

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RADIO SCIENCE 1999年第5期34卷 1077-1083页

作者： Luce, H Crochet, M Hanuise, C Yamamoto, M Fukao, S Univ Toulon & Var Lan Sondages Electromagnet Environm Terr F-83957 La Garde France Kyoto Univ Ctr Radio Atmospher Sci Uji Kyoto 611 Japan

The frequency domain interferometry (FDI) technique has been developed for probing thin layered structures of the atmosphere. The position and thickness of a single layer embedded within the scattering volume can be deduced from the complex normalized cross correlation (coherence) of received signals at two closely spaced frequencies. Applied in the vertical pointing direction, this technique identified layered structures ("FDI layers") of 50-200 m in thickness in the lower atmosphere. These structures are 1 order of magnitude thicker than observed temperature sheets (about 10-m thick) which are very likely responsible for the main part of the VHF radar echoes in vertical direction. In this paper, although the ambiguity of the dual FDI technique is well known, we emphasize that the FDI layers do not necessarily correspond to a single atmospheric layer;they can also be interpreted as a more complex structure of very thin atmospheric layers. A simple model, introduced as an example, shows that the FDI layer thickness can also approximately be interpreted as the vertical separation of two very thin atmospheric layers. This result can explain by itself the differences between the estimated thicknesses by balloon and FDI radar techniques. Finally, we stress that comparisons with high-resolution in situ measurements are urgently needed for interpreting the FDI layers.

关键词： Meteorological radar Atmospheric structure Interferometry Frequencydomain analysis Thickness measurement Scattering Radar receivers correlation detectors Radio balloons Frequency domain interferometry Atmospheric layers

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