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Respiratory noise correction using phase information
Magnetic Resonance Imaging, 2008Respiratory noise is a confounding factor in functional magnetic resonance imaging (MRI) data analysis. A novel method called Respiratory noise Correction using Phase information is proposed to retrospectively correct for the respiratory noise in functional MRI (fMRI) time series.
Hu, Cheng, Yu, Li
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Phase noise suppression in MIMO OFDM systems with incoherent phase noise
2011 - MILCOM 2011 Military Communications Conference, 2011This paper presents a remedy to the phase noise problem in the multiple-input/multiple-output (MIMO), orthogonal frequency division multiplexing (OFDM) systems with incoherent phase noise. The phase noise incoherence (PNI) is a common condition that arises when different channels in a MIMO system use different local oscillator (LO) signals. Phase noise
Babak Daneshrad, null Weijun Zhu
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Phase noise in oscillators: DAEs and colored noise sources
1998 IEEE/ACM International Conference on Computer-Aided Design. Digest of Technical Papers (IEEE Cat. No.98CB36287), 1998Oscillators are key components of electronic systems. Undesired perturbations, i.e. noise, in practical electronic systems adversely affect the spectral and timing properties of oscillators resulting in phase noise, which is a key performance limiting factor, being a major contributor to bit-error-rate (BER) of RF communication systems, and creating ...
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Phase noise effects in QAM systems
Proceedings of 8th International Symposium on Personal, Indoor and Mobile Radio Communications - PIMRC '97, 2002The effects of oscillator phase noise on the performance of digital transmission systems employing QAM are investigated. The model used for the phase noise is a Wiener-Levy process which allows a moment characterization of the filtered phase noise.
CORVAJA, ROBERTO, PUPOLIN, SILVANO
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Izmeritel`naya Tekhnika
The necessity of developing of an initial relative phase noise level standard to ensure metrological traceability of small values of phase noise measurements. The relevance of creating a standard is due to the increased requirements for short-term frequency stability of modern signal generators and highly stable quartz oscillators, characterized by a ...
Nikolay R. Bazhenov +2 more
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The necessity of developing of an initial relative phase noise level standard to ensure metrological traceability of small values of phase noise measurements. The relevance of creating a standard is due to the increased requirements for short-term frequency stability of modern signal generators and highly stable quartz oscillators, characterized by a ...
Nikolay R. Bazhenov +2 more
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AM noise impact on low level phase noise measurements
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2002The influence of the source AM noise in microwave residual phase noise experiments is investigated. The noise floor degradation problem, caused by the parasitic detection of this type of noise by an unperfectly balanced mixer, is solved thanks to a refinement of the quadrature condition.
Gilles, Cibiel +3 more
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1995
A new derivation of the canonical description of optical phase is given, and it is shown that any covariant method of phase estimation (such as heterodyne phase detection) may be interpreted as a noisy measurement of canonical phase. An important example is Gaussian noise, and it is demonstrated that phase-based communication is relatively robust with ...
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A new derivation of the canonical description of optical phase is given, and it is shown that any covariant method of phase estimation (such as heterodyne phase detection) may be interpreted as a noisy measurement of canonical phase. An important example is Gaussian noise, and it is demonstrated that phase-based communication is relatively robust with ...
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Noise-immune phase unwrapping algorithm
Applied Optics, 1989A new phase unwrapping algorithm is proposed which combines noise immunity with computational efficiency. It is based on the requirement that the unwrapped map should be independent of the route by which unwrapping takes place.
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VCO phase noise characterization
Proceedings of 40th Midwest Symposium on Circuits and Systems. Dedicated to the Memory of Professor Mac Van Valkenburg, 2002A measurement procedure is developed specifically to characterize the phase noise of low Q, relatively unstable free-running oscillators. The phase noise performance of a VCO is evaluated theoretically using nonlinear computer aided design (CAD) tool and experimentally using phase noise measurement system.
D.Q. Xu, G.R. Branner
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IEEE Transactions on Wireless Communications, 2010
In this article we examine the effect of phase noise on a multi-antenna beamforming system. The effect is quantified in terms of error vector magnitude (EVM). It is shown that using independent phase noise sources improves EVM performance in the main lobe.
Thomas Hohne, Ville Ranki
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In this article we examine the effect of phase noise on a multi-antenna beamforming system. The effect is quantified in terms of error vector magnitude (EVM). It is shown that using independent phase noise sources improves EVM performance in the main lobe.
Thomas Hohne, Ville Ranki
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