Results 31 to 40 of about 16,290 (166)
Modeling and analysis for dynamical Doppler shifts on terahertz communication signals propagating in inhomogeneous hypersonic plasma sheath [PDF]
AIP AdvancesPrevious studies have shown that terahertz (THz) signals could penetrate hypersonic plasma sheaths. Thus, it is considered to be a potential solution to the “blackout” problem.
Xiangmeng Lin +4 more
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The Ray Theory of Doppler Frequency Shifts [PDF]
Australian Journal of Physics, 1968 A general expression is obtained according to ray theory for the Doppler frequency shift observed when both receiver and transmitter are in motion in a time-varying anisotropic but lossless medium. The result is obtained using Hamilton's optical method.
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New Journal of Physics, 2016 The Doppler effect, the shift in the frequency of sound due to motion, is present in both classical gases and quantum superfluids. Here, we perform an in situ , minimally destructive measurement, of the persistent current in a ring-shaped, superfluid ...
A Kumar +5 more
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Frequency Spectrum of Doppler-shifted Whistler-mode Signals [PDF]
Nature, 1965 To further our knowledge of very-low-frequency signals received via the whistler mode of propagation we have constructed a 25-channel spectrum analyser. Other work1,2 has shown the existence of apparent Doppler shifts on these signals of up to two or three parts in 105 of the carrier frequency; but the equipment used did not allow the variations of ...
R. A. MORRIS, N. POLETTI
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Effect of Hematocrit upon the Shift in Doppler Frequency
Experimental Biology and Medicine, 1971 ConclusionOver a wide range of erythrocyte concentration (10-68 vol%) there is not an appreciable change in the Doppler frequency shift when blood flow conditions and temperature remain constant.
D D, Michie, C P, Cain
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Sonar micro-Doppler effect induced by ship oscillatory motion in waves: Phenomenon, model, and experimentation [PDF]
JASA Express LettersTraditional research attributes the modulated sidebands of ship radiation line-spectrum signals to reflections off rough ocean surfaces, but the Doppler effect caused by vessel motion may also contribute.
Minhao Wang +3 more
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A Photonic Approach for Doppler Frequency Shift Measurement With Dispersion Medium
IEEE Photonics Journal, 2020 We propose and experimentally demonstrate a novel and simple approach to identifying both the direction and value of Doppler frequency shift (DFS) in this paper.
Chongyin Yi, Hao Chi, Tao Jin
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Estimation of Rice Factor Ratio for Doubly Selective Fading Channels
IEEE Access, 2020 In wireless communication systems, Rice factor ratio (RFR) defined as K/(1 + K) is a key parameter not only to evaluate the quality of communication channel since it can reveal the severity of the small-scale fading, but also to be employed as a priori ...
Junfeng Wang +6 more
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Doppler frequency analysis for sound-field sampling with moving microphones
Frontiers in Signal ProcessingMoving microphones allow for the fast acquisition of sound-field data that encode acoustic impulse responses in time-invariant environments. Corresponding decoding algorithms use the knowledge of instantaneous microphone positions for relating the ...
Fabrice Katzberg +3 more
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A Novel Acquisition Algorithm Based on PMF-apFFT for BOC Modulated Signals
IEEE Access, 2019 Large Doppler shifts are inherent to high-speed relative motion between receiver and satellite and are likely to cause major problems during the code phase acquisition due to the introduced frequency ambiguity.
Yi Pan +3 more
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