Artykuły w czasopismach: „Doppler theory”

1

Tinto, Massimo. "Theory of spacecraft Doppler tracking". Banach Center Publications 41, nr 2 (1997): 145–54. http://dx.doi.org/10.4064/-41-2-145-154.

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Ranganath, G. S. "!Quantum theory of the Doppler effect". Resonance 1, nr 10 (październik 1996): 76–78. http://dx.doi.org/10.1007/bf02839100.

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NISHIMURA, RICK A., FLETCHER A. MILLER, MARK J. CALLAHAN, ROBERT C. BENASSI, JAMES B. SEWARD i A. JAMIL TAJIK. "Doppler Echocardiography: Theory, Instrumentation, Technique, and Application". Mayo Clinic Proceedings 60, nr 5 (maj 1985): 321–43. http://dx.doi.org/10.1016/s0025-6196(12)60540-0.

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4

Hines, Colin O. "The Doppler spread theory and parameterization revisited". Journal of Atmospheric and Solar-Terrestrial Physics 66, nr 11 (lipiec 2004): 949–56. http://dx.doi.org/10.1016/j.jastp.2004.02.005.

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Choi, Yang-Ho. "Systematic approach to the relativistic Doppler effect based on a test theory". Canadian Journal of Physics 94, nr 10 (październik 2016): 1064–70. http://dx.doi.org/10.1139/cjp-2016-0340.

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Numerous experiments have been carried out to validate the Lorentz transformation or to find possible violations of Lorentz invariance, based on test theories to test special relativity. The test theory of Mansouri and Sexl (MS) provides a general framework for the transformation of inertial frames, presuming a preferred system of reference. Based on the MS framework, this paper systematically approaches the relativistic Doppler effect such that its dependency on transformation coefficients and parameters can be investigated. The Doppler effect is formulated in a complex Euclidean space where time is represented with imaginary numbers. Two formulae of the Doppler effect, which have been derived in an arbitrary transformation within the MS framework, are presented: one between an inertial frame and the preferred one and the other between arbitrary inertial frames. It is shown from the former formulation that the Doppler effect is independent of the synchronization of clocks, which implies that the Doppler-shifted frequency in the absolute synchronization is the same as that in the standard synchronization. The latter formula can allow us to find Doppler shifts without information on the velocities of inertial frames relative to the preferred frame. Exploiting these theoretical results, we examine the transverse and the longitudinal Doppler effects in detail.

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6

Zhou, Chang, Zhen-Bo Zhu i Zi-Yue Tang. "A Novel Waveform Design Method for Shift-Frequency Jamming Confirmation". International Journal of Antennas and Propagation 2018 (2.07.2018): 1–13. http://dx.doi.org/10.1155/2018/1569590.

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Shift-frequency jamming is generally used to form range false targets for ground-based early-warning radar systems; the frequency shift value of such interference is larger than the Doppler shift value of the moving target, and the key element to suppress the shift-frequency jamming is the frequency shift value estimation. However, in the low- or medium-pulse repetition frequency (PRF) mode, it is challenging to estimate the accurate frequency shift due to the velocity ambiguity. To solve this problem, a novel sparse Doppler-sensitive waveform is designed based on the ambiguity function theory, where the basic idea is to design a waveform sensitive to a specific Doppler but insensitive to other Dopplers; therefore, this waveform can recognize the specific Doppler of the target unambiguously. To apply the designed waveform in practice, the detection and estimation processing flow is provided based on the waveform diversity technique and the family of the sparse Doppler-sensitive waveforms. Simulation experiments are presented to validate the efficiency of the proposed method, and we conclude that the advantage of this method is that it can be used to confirm the specific Doppler of the target unambiguously with few pulses even under the condition of a low PRF.

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Zhang, Yu-xi, Jin-ping Sun, Bing-chen Zhang i Wen Hong. "Doppler Ambiguity Resolution Based on Compressive Sensing Theory". Journal of Electronics & Information Technology 33, nr 9 (30.09.2011): 2103–7. http://dx.doi.org/10.3724/sp.j.1146.2011.00073.

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8

Moriconi, M. "Special theory of relativity through the Doppler effect". European Journal of Physics 27, nr 6 (9.10.2006): 1409–23. http://dx.doi.org/10.1088/0143-0807/27/6/015.

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9

Capron, B. A., A. S. Marathay i M. Sargent. "Theory of two-photon Doppler-broadened probe absorption". Optics Letters 11, nr 2 (1.02.1986): 70. http://dx.doi.org/10.1364/ol.11.000070.

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Xiao, Yongshun. "Doppler effect in larval biology: theory and applications". Ecological Modelling 165, nr 1 (lipiec 2003): 1–22. http://dx.doi.org/10.1016/s0304-3800(02)00356-3.

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Meneghini, R., S. W. Bidwell, L. Liao, R. Rincon i G. M. Heymsfield. "Differential-frequency Doppler weather radar: Theory and experiment". Radio Science 38, nr 3 (7.02.2003): n/a. http://dx.doi.org/10.1029/2002rs002656.

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Jensen, J., O. S. Mortensen i E. N. Svendsen. "Doppler Effect Derived from Time-Dependent Perturbation Theory". Journal of Molecular Spectroscopy 158, nr 2 (kwiecień 1993): 484–86. http://dx.doi.org/10.1006/jmsp.1993.1093.

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13

Steinbach, Arden. "Electromagnetic theory of range-Doppler imaging in laser radar I: Scattering theory". Journal of the Optical Society of America A 8, nr 8 (1.08.1991): 1287. http://dx.doi.org/10.1364/josaa.8.001287.

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BERTOTTI, BRUNO. "ON THE THEORY OF THE DOPPLER EFFECT IN A MOVING MEDIUM". Modern Physics Letters A 13, nr 01 (10.01.1998): 1–6. http://dx.doi.org/10.1142/s0217732398000024.

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The increase in the accuracy of Doppler measurements in space requires a rigorous definition of the observed quantity when the propagation occurs in a moving, and possibly dispersive medium, like the solar wind. This is usually done in two divergent ways: in the phase viewpoint it is the time derivative of the correction to the optical path; in the ray viewpoint the signal is obtained form the deflection produced in the ray. They can be reconciled by using the time derivative of the optical path in the Lagrangian sense, i.e. differentiating from ray to ray. To rigorously derive this result an understanding, through relativistic Hamiltonian theory, of the delicate interplay between rays and phase is required; a general perturbation theorem which generalizes the concept of the Doppler effect as a Lagrangian derivative is proved. Relativistic retardation corrections O(v) are obtained, well within the expected sensitivity of Doppler experiments near solar conjunction.

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15

Huang, Jing, Bao Hua Zhu, Yuan Yuan Wu i Xi Huang. "Laser Cooling Mechanisms of Chromium Atomic Beam". Advanced Materials Research 189-193 (luty 2011): 3768–71. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.3768.

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A theoretical investigation of 52Cr atomic beam in optical traps was reported, the Doppler and sub-Doppler laser cooling forces were discussed and some characteristics of these forces were shown based on the semi-classical theory. The simulative results indicate that the atomic beam can be collimated by these laser cooling forces, especially by sub-Doppler laser cooling force.

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16

Gandini, Augusto. "The heuristically-based generalized perturbation theory". EPJ Nuclear Sciences & Technologies 7 (2021): 7. http://dx.doi.org/10.1051/epjn/2021003.

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The generalized perturbation method is described relevant to ratios of bi-linear functionals of the real and adjoint neutron fluxes of critical multiplying systems. Simple linear analysis for optimization and sensitivity studies are then feasible relative to spectrum and space-dependent quantities, such as Doppler and coolant void reactivity effects in fast reactors.

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17

Gray, Trevor, i Walter Blanchard. "Airborne Doppler Radar Development by the Decca Company". Journal of Navigation 61, nr 1 (10.12.2007): 71–85. http://dx.doi.org/10.1017/s0373463307004511.

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This paper is intended as an historical document describing the entry and success of the Decca Radar Company into the production of Doppler-based navigation units. It is based on an original personal paper written in about 1970 by Trevor Gray, then Head of Doppler Department, Decca Radar, updated and edited with additions by Walter Blanchard (past President of the RIN) assisted by Trevor Gray in May 2007. The paper first covers the basic theory and principles of Doppler radar systems, continues through the setting up of the Decca Doppler Department in the mid-1950s and the production of the first transistor-based Doppler system. Success led to the development of both civil and military Doppler systems culminating in the Decca Doppler 70 Series which was fitted to some 30 types of aircraft and helicopters, worldwide.

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18

Wu, Xing Cun, Ping Gong, Hai Jun Song i Hui Zhi Zou. "An FFT-Based Approach for Carrier Frequency Domain Acquisition in Spread Spectrum TT&C System". Applied Mechanics and Materials 135-136 (październik 2011): 211–16. http://dx.doi.org/10.4028/www.scientific.net/amm.135-136.211.

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Acquisition time of precision ranging code is long under the conditions of large Doppler shift, the carrier frequency domain FFT-based fast acquisition theory was analyzed, and the method of carrier Doppler compensation estimates to complete the PN code Doppler compensation was directly used in spread spectrum ranging signal acquisition. Comparing with the traditional parallel acquisition approach, the Doppler frequency estimation accuracy and acquisition speed is greatly improved, the acquisition time is shorter than long code segment with the traditional parallel acquisition method. Comparing with the method of short code supporting for long code, the channel energy is saved.

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19

Guermeur, F., Yannick Bailly i B. Martinez. "DOPPLER GLOBAL VELOCIMETRY. RANGES OF ACCESSIBLE VELOCITIES. PART I: THEORY". Journal of Flow Visualization and Image Processing 23, nr 3-4 (2016): 215–32. http://dx.doi.org/10.1615/jflowvisimageproc.2017019015.

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20

XING Bo, 邢. 博., 余祖俊 YU Zu-jun, 许西宁 XU Xi-ning i 朱力强 ZHU Li-qiang. "Rail defect monitoring based on laser Doppler frequency shift theory". Chinese Optics 11, nr 6 (2018): 991–1000. http://dx.doi.org/10.3788/co.20181106.0991.

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21

O’Callaghan, M. J., i J. Cooper. "Theory of velocity-dependent, collision-broadened, Doppler-free line shapes". Physical Review A 39, nr 12 (1.06.1989): 6206–23. http://dx.doi.org/10.1103/physreva.39.6206.

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22

Strean, R. F., L. D. Mitchell i A. J. Barker. "Global noise characteristics of a laser Doppler vibrometer—I. Theory". Optics and Lasers in Engineering 30, nr 2 (sierpień 1998): 127–39. http://dx.doi.org/10.1016/s0143-8166(98)00014-1.

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23

Naumov, A. N., A. A. Podshivalov, K. N. Drabovich, R. B. Miles i A. M. Zheltikov. "Theory of Doppler-free spectroscopy with λ-thick vapor cells". Physics Letters A 289, nr 4-5 (październik 2001): 207–12. http://dx.doi.org/10.1016/s0375-9601(01)00617-x.

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24

Stern, Michael D. "Laser Doppler velocimetry in blood and multiply scattering fluids: theory". Applied Optics 24, nr 13 (1.07.1985): 1968. http://dx.doi.org/10.1364/ao.24.001968.

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25

Hu, Fei, Chang Qing Shen, Fang Liu, Ao Zhang i Fan Rang Kong. "Doppler Shift Elimination Method Based on Instantaneous Frequency Estimation for the Wayside Acoustic Signal". Applied Mechanics and Materials 333-335 (lipiec 2013): 510–15. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.510.

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The phenomenon of Doppler Shift leads to the difficulty for fault diagnosis of train bearings with a high moving speed. So the elimination of the Doppler shift should be implemented firstly. A Doppler Shift elimination method for the wayside acoustic signal is proposed. The instantaneous frequency estimation based on STFT was applied to attain the IF vector. According to the acoustic theory of Morse, the data fitting was then carried out to achieve the fitting IFs, with which the re-sampling sequence could be established to eliminate Doppler Shift. To demonstrate the validity of this method, an experiment with the synthetic signal containing several frequency components had been carried out. The results show that the re-sampled signal was revised without Doppler Shift.

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26

Wang, Xin Long, Chuan Jun Li i Xing Cheng Li. "Research on INS-Aided GNSS Carrier Tracking Loop in High Dynamic Circumstance". Applied Mechanics and Materials 464 (listopad 2013): 215–21. http://dx.doi.org/10.4028/www.scientific.net/amm.464.215.

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GNSS receiver will produce a large Doppler shift in high dynamic environment, thus causing lock-lose of the tracking loop. INS-aided GNSS tightly coupled system can improve tracking performance in high dynamic environment by introducing the Doppler information estimated by INS. Through analyzing by the theory of closed loop control system theory and numerical simulation of the INS-aided carrier tracking loop, the results show that INS-aided carrier tracking loop can obviously improve the stability of carrier tracking performance and anti-jamming ability of the satellite navigation receiver in high dynamic circumstance.

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27

Kim, Yeong M., i Song B. Park. "Modeling of Doppler Signal considering Sample Volume and Field Distribution". Ultrasonic Imaging 11, nr 3 (lipiec 1989): 175–96. http://dx.doi.org/10.1177/016173468901100302.

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The ultrasound Doppler amplitude spectrum for a single scatterer and the power spectrum for multiple scatterers were calculated in terms of the echo signal from scatterers crossing the sample volume, defined by the transmitted pulse and the diffracted field distribution for cw. The observation time for the Doppler signal is also considered. Statistical parameters such as mean and variance of the Doppler power spectrum are studied as continuous functions of the intersection angle between the beam axis and the flow direction, the pulse length and the viewing position. The derived equations are valid whether the transit time is governed by the pulse length, or beam geometry, or both. It is shown that the Doppler power spectra calculated by the proposed model and by the Doppler signal obtained from field theory are in good agreement. It is also shown that, when the Doppler signal broadening due to the transmitted pulse and beam geometry is constant without regard to the intersection angle, the degree of spread of the velocity distribution can be estimated from the variance of the Doppler power spectrum measured by the Doppler system once the intersection angle is known.

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28

Hermawan, N., T. Ishii, Y. Yamakoshi i Y. Saijo. "Large Amplitude Harmonic Vibration under Pulse Doppler Measurement". Journal of Physics: Conference Series 2071, nr 1 (1.10.2021): 012034. http://dx.doi.org/10.1088/1742-6596/2071/1/012034.

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Abstract A flow velocity or tissue motion can be measured by pulse Doppler method. However, when the method is applied to a sinusoid motion or harmonic vibration, the estimation result is deviated. In this paper, the generalized theory of pulse Doppler measurement to the sinusoid motion is explained and the relation between the estimation deviation and the real value is given. Furthermore, a special case of binary velocity estimation is expanded and simulated with different parameters. This simulation result suggested that different selection of parameters may fundamentally affect the output of pulse Doppler estimation.

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29

Куклин, А. В., i В. А. Куклин. "Волновая природа поперечного эффекта Доплера и аномалии красного" и синего" смещения частоты электромагнитной волны движущегося источника излучения". Журнал технической физики 89, nr 1 (2019): 137. http://dx.doi.org/10.21883/jtf.2019.01.46975.135-18.

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AbstractThe electromagnetic field of a harmonic oscillator moving at a constant velocity has been analyzed. The expression for calculating the Doppler frequency shift at relativistic velocities of its motion is derived using the classical electromagnetic theory. It is shown that the transverse Doppler effect is a special case and also differs from zero in the wave theory. With an increasing velocity of the radiation source, the “red” frequency shift in an electromagnetic wave prevails over the “blue” shift more strongly. The noncontradictory nature of the proposed model relative to the well-known experimental data has been demonstrated.

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30

Meng, Xianming. "A Photon Density Theory Explaining Experiments on High-order Doppler Effect". International Journal of Physics 9, nr 6 (5.12.2021): 308–17. http://dx.doi.org/10.12691/ijp-9-6-6.

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31

Giuliani, Giuseppe. "Experiment and theory: the case of the Doppler effect for photons". European Journal of Physics 34, nr 4 (24.05.2013): 1035–47. http://dx.doi.org/10.1088/0143-0807/34/4/1035.

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32

Liu, W. K., i A. S. Dickinson. "Theory of the inelastic lineshape for two-step sub-Doppler excitation". Journal of Physics B: Atomic, Molecular and Optical Physics 24, nr 6 (28.03.1991): 1259–72. http://dx.doi.org/10.1088/0953-4075/24/6/015.

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33

Liu Zijun, 刘子君, 崔骊水 Cui Lishui i 谢代梁 Xie Dailiang. "Theory Analysis and Measurement for Interference Fringes of Laser Doppler Velocimeter". Chinese Journal of Lasers 44, nr 8 (2017): 0804001. http://dx.doi.org/10.3788/cjl201744.0804001.

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34

Bezverbnyi, A. V. "Bipolar harmonics method in the semiclassical theory of sub-doppler cooling". Journal of Experimental and Theoretical Physics 91, nr 5 (listopad 2000): 921–37. http://dx.doi.org/10.1134/1.1334982.

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35

Korb, C. Laurence, Bruce M. Gentry, S. Xingfu Li i Cristina Flesia. "Theory of the double-edge technique for Doppler lidar wind measurement". Applied Optics 37, nr 15 (20.05.1998): 3097. http://dx.doi.org/10.1364/ao.37.003097.

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36

Weitzel, William F., Jonathan M. Rubin, Richard D. Swartz, David J. Woltmann i Joseph M. Messana. "Variable Flow Doppler for Hemodialysis Access Evaluation: Theory and Clinical Feasibility". ASAIO Journal 46, nr 1 (styczeń 2000): 65–69. http://dx.doi.org/10.1097/00002480-200001000-00018.

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Calzolai, M., L. Capineri, A. Fort, L. Masotti, S. Rocchi i M. Scabia. "A 3-D PW ultrasonic Doppler flowmeter: theory and experimental characterization". IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control 46, nr 1 (styczeń 1999): 108–13. http://dx.doi.org/10.1109/58.741518.

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38

Kopeikin, S. M., i L. M. Ozernoy. "Post‐Newtonian Theory for Precision Doppler Measurements of Binary Star Orbits". Astrophysical Journal 523, nr 2 (październik 1999): 771–85. http://dx.doi.org/10.1086/307759.

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39

Rosenqvist, Anders. "Asymptotic theory for a two-step pseudo-linear Doppler-bearing tracker". Computational Statistics & Data Analysis 21, nr 6 (czerwiec 1996): 647–60. http://dx.doi.org/10.1016/0167-9473(95)00034-8.

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40

Saillard, Marc, Philippe Forget, Gabriel Soriano, Maminirina Joelson, Pierre Broche i Philip Currier. "Sea surface probing with L-band Doppler radar: experiment and theory". Comptes Rendus Physique 6, nr 6 (lipiec 2005): 675–82. http://dx.doi.org/10.1016/j.crhy.2005.06.008.

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41

Schroeder, Paul. "Doppler and an End of Expansion". Energy and Earth Science 4, nr 1 (9.03.2021): p14. http://dx.doi.org/10.22158/ees.v4n1p14.

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The concept today is that our universe is in a state of expansion as everything is moving away from us, and away from everywhere. This idea is specifically a conclusion to the finding of the frequency of the waves of light from the source being distorted, theoretically by the motion of the source relative to the observer. The frequency variation is called Doppler which was originally assigned to distorted sound from arriving trains. This is an analysis of Doppler theory that revels that a redshift of star light beams occur when the stars are “revolving” relative to an observer (such as us on earth). Everything in space does revolve around an observer. Think about this!

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42

O'Toole, Simon, Chris Tinney i Hugh Jones. "Selection effects in Doppler velocity planet searches". Proceedings of the International Astronomical Union 3, S249 (październik 2007): 111–14. http://dx.doi.org/10.1017/s1743921308016475.

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AbstractThe majority of extra-solar planets have been discovered by measuring the Doppler velocities of the host star. Like all exoplanet detection methods, the Doppler method is rife with observational biases. Before any robust comparison of mass, orbital period and eccentricity distributions can be made with theory, a detailed understanding of these selection effects is required, something which up to now is lacking. We present here a progress report on our analysis of the selection effects present in Anglo-Australian Planet Search data, including the methodology used and some preliminary results.

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43

Gerkema, Theo, Leo R. M. Maas i Hans van Haren. "A Note on the Role of Mean Flows in Doppler-Shifted Frequencies". Journal of Physical Oceanography 43, nr 2 (1.02.2013): 432–41. http://dx.doi.org/10.1175/jpo-d-12-090.1.

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Abstract The purpose of this paper is to resolve a confusion that may arise from two quite distinct definitions of “Doppler shifts”: both are used in the oceanographic literature but they are sometimes conflated. One refers to the difference in frequencies measured by two observers, one at a fixed position and one moving with the mean flow—here referred to as “quasi-Doppler shifts.” The other definition is the one used in physics, where the frequency measured by an observer is compared to that of the source. In the latter sense, Doppler shifts occur only if the source and observer move with respect to each other; a steady mean flow alone cannot create a Doppler shift. This paper rehashes the classical theory to straighten out some misconceptions. It is also discussed how wave dispersion affects the classical relations and their application.

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Wolde, Mengistu, Alessandro Battaglia, Cuong Nguyen, Andrew L. Pazmany i Anthony Illingworth. "Implementation of polarization diversity pulse-pair technique using airborne W-band radar". Atmospheric Measurement Techniques 12, nr 1 (15.01.2019): 253–69. http://dx.doi.org/10.5194/amt-12-253-2019.

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Abstract. This work describes the implementation of polarization diversity on the National Research Council Canada W-band Doppler radar and presents the first-ever airborne Doppler measurements derived via polarization diversity pulse-pair processing. The polarization diversity pulse-pair measurements are interleaved with standard pulse-pair measurements with staggered pulse repetition frequency, this allows a better understanding of the strengths and drawbacks of polarization diversity, a methodology that has been recently proposed for wind-focused Doppler radar space missions. Polarization diversity has the clear advantage of making possible Doppler observations of very fast decorrelating media (as expected when deploying Doppler radars on fast-moving satellites) and of widening the Nyquist interval, thus enabling the observation of very high Doppler velocities (up to more than 100 m s−1 in the present work). Crosstalk between the two polarizations, mainly caused by depolarization at backscattering, deteriorated the quality of the observations by introducing ghost echoes in the power signals and by increasing the noise level in the Doppler measurements. In the different cases analyzed during the field campaigns, the regions affected by crosstalk were generally associated with highly depolarized surface returns and depolarization of backscatter from hydrometeors located at short ranges from the aircraft. The variance of the Doppler velocity estimates can be well predicted from theory and were also estimated directly from the observed correlation between the H-polarized and V-polarized successive pulses. The study represents a key milestone towards the implementation of polarization diversity in Doppler space-borne radars.

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Zhang, Ao, Fang Liu i Fan Rang Kong. "Doppler Distortion Removal Method for Multiple Acoustic Sources". Applied Mechanics and Materials 373-375 (sierpień 2013): 874–79. http://dx.doi.org/10.4028/www.scientific.net/amm.373-375.874.

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In wayside fault diagnosis of train bearings, the phenomenon of Doppler distortion in the acoustic signal of moving acoustic source acquired with a microphone leads to the difficulty for signal analysis. In this paper, a new method based on Dopplerlet transform and re-sampling is proposed to eliminate the Doppler distortion of multiple acoustic sources which provide a reference for wayside fault diagnosis of train bearings. Firstly, search the parameters space to find the primary functionsDopplerlet atoms. According to the Morse acoustic theory, the instantaneous frequency of the Dopplerlet atom which we choose to remove Doppler distortion of the corresponding acoustic source can be acquired. Then, the re-sampling sequence can be established in time domain. Through the resample, the Doppler distortion can be removed. In the end of this paper, an experiment with practical acoustic signals is carried out, and the results verified the effectiveness of this method.

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46

Flint, T., L. Nokes, M. Maheson i J. P. Woodcock. "Using the Doppler Effect to Measure the Vibration of Human Bones: In Vitro Studies". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 208, nr 2 (czerwiec 1994): 127–29. http://dx.doi.org/10.1243/pime_proc_1994_208_275_02.

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A novel application of ultrasound Doppler theory to the measurement of bone vibration is described. The theory and experimental apparatus is outlined and its initial calibration and in vitro assessment reported. It is speculated that this method may be used clinically in order to monitor in vivo bone fracture healing.

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Gai, Vasiliy E., i Anna M. Bogdan. "Classification of the Signatures for Doppler Radar from the Standpoint of Active Perception Theory". Key Engineering Materials 685 (luty 2016): 262–66. http://dx.doi.org/10.4028/www.scientific.net/kem.685.262.

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This article describes the signals classification method when signals recording by land-based Doppler radar from different sources. It also presents various systems attributes defined within the active perception theory, which can be used to describe the signals. The results of computational experiments are presented.

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48

Zhang, Yunjian, Zhenmiao Deng, Jianghong Shi, Linmei Ye, Maozhong Fu i Chen Zhao. "Doppler Ambiguity Resolution Based on Random Sparse Probing Pulses". Journal of Electrical and Computer Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/251849.

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A novel method for solving Doppler ambiguous problem based on compressed sensing (CS) theory is proposed in this paper. A pulse train with the random and sparse transmitting time is transmitted. The received signals after matched filtering can be viewed as randomly sparse sampling from the traditional fixed-pulse repetition frequency (PRF) echo signals. The whole target echo could be reconstructed via CS recovery algorithms. Through refining the sensing matrix, which is equivalent to increase the sampling frequency of target characteristic, the Doppler unambiguous range is enlarged. In particular, Complex Approximate Message Passing (CAMP) algorithm is developed to estimate the unambiguity Doppler frequency. Cramer-Rao lower bound expressions are derived for the frequency. Numerical simulations validate the effectiveness of the proposed method. Finally, compared with traditional methods, the proposed method only requires transmitting a few sparse probing pulses to achieve a larger Doppler frequency unambiguous range and can also reduce the consumption of the radar time resources.

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Larson, D. J. "An Absolute Theory of Doppler Shifts and the Michelson‐Morley Null Result". Physics Essays 6, nr 1 (marzec 1993): 66–80. http://dx.doi.org/10.4006/1.3029041.

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Nusinovich, G. S., M. Korol i E. Jerby. "Theory of the anomalous Doppler cyclotron-resonance-maser amplifier with tapered parameters". Physical Review E 59, nr 2 (1.02.1999): 2311–21. http://dx.doi.org/10.1103/physreve.59.2311.

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