Results 161 to 170 of about 1,683,790 (202)
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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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1997
The conversion of low frequency noise into phase noise in a high frequency oscillator depends strongly on the active device type and operating conditions. Experimental setups are presented to achieve the best choice of a transistor to be used in low noise oscillators and to study the correlation between phase noise and low frequency noise.
O. Llopis +5 more
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The conversion of low frequency noise into phase noise in a high frequency oscillator depends strongly on the active device type and operating conditions. Experimental setups are presented to achieve the best choice of a transistor to be used in low noise oscillators and to study the correlation between phase noise and low frequency noise.
O. Llopis +5 more
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Physics in Technology, 1985
The idea of silencing noise by producing complementary 'negative waves' goes back over a hundred years. Highly sophisticated control systems are now helping to make the idea a reality, but many practical problems ...
J.E. Ffowcs Williams +2 more
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The idea of silencing noise by producing complementary 'negative waves' goes back over a hundred years. Highly sophisticated control systems are now helping to make the idea a reality, but many practical problems ...
J.E. Ffowcs Williams +2 more
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1998
A frequency synthesizer or signal source is expected to provide a pure spectral signal. There should be no unwanted amplitude or frequency/phase modulation in the output spectrum. As we will discuss shortly, undesired phase modulation on the local oscillator in communications receivers, can reduce the channel selectivity and degrade the bit error rate ...
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A frequency synthesizer or signal source is expected to provide a pure spectral signal. There should be no unwanted amplitude or frequency/phase modulation in the output spectrum. As we will discuss shortly, undesired phase modulation on the local oscillator in communications receivers, can reduce the channel selectivity and degrade the bit error rate ...
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Noise-Induced Phase Transitions
1999Phase transitions constitute one of the most interesting features exhibited by spatially extended systems. This chapter analyzes the effect of noise on phase transitions taking place between different steady states of a system. As we will see, noise can affect preexisting phase transitions, or even induce new ones.
Jordi García-Ojalvo, José M. Sancho
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Phase Noise measurement techniques
2011 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2011), 2011Low Phase Noise measurement is a demanding trend of the military and instrumentation market. To improve phase noise of components of a Radar or communication system, it is mandatory to improve also the measurement testers and techniques. This paper deals with techniques like phase lock loops, frequency discriminators, residual noise, AM noise, on CW or
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Phased array noise considerations
NTC '91 - National Telesystems Conference Proceedings, 2002Several concepts and formulae are presented that are useful in the examination of the signal-to-noise performance of phased array antennas with dissimilar signal paths or subarray sizes. It is demonstrated that, in most such cases, aperture illumination efficiency remains an accurate indication of array antenna noise performance. >
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