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A quadrature UWB frequency synthesizer with dynamic settling-time calibration
2013 IEEE International Symposium on Circuits and Systems (ISCAS2013), 2013This paper presents a quadrature DLL-based architecture for WiMedia ultra-wideband (UWB) frequency synthesis. I and Q carriers are directly generated by combining the quadrature multi-phase outputs of the DLL, using separate edge combiners (EC). A variable-stage voltage-controlled delay line (VCDL) scheme is proposed to provide the corresponding output
Amin Ojani +2 more
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Coral larvae settle at a higher frequency on red surfaces
Coral Reefs, 2011Although chemical cues serve as the primary determinants of larval settlement and metamorphosis, light is also known to influence the behavior and the settlement of coral planulae. For example, Porites astreoides planulae settle preferentially on unconditioned red substrata.
B. Mason, M. Beard, M. W. Miller
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Fast settling frequency synthesizer with two‐point channel control paths
International Journal of Circuit Theory and Applications, 2011SUMMARYA frequency synthesizer with low‐power and very short settling time is introduced, which utilizes two‐point channel control paths. While the main‐path is the same as normal channel controls, a digital‐to‐analog converter (DAC) with tunable gain is used for the compensation‐path to form a feed‐forward direct voltage‐controlled oscillator (VCO ...
Sangho Shin, Sung-Mo Kang
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FAST SETTLING HYBRID FREQUENCY SYNTHESIZER
Radio Engineering and Telecommunication SystemThis paper presents a hybrid synthesizer based on a high-speed digital-to-analog converter (DAC) and a phase-locked loop (PLL) system with enhanced frequency switching speed. The switching speed is increased through the use of a special system, the operating principle of which involves changing the parameters of the low-pass loop filter (LPF) during ...
K. A. Yakimenko +3 more
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Settling time specifications: phase or frequency?
Proceedings of MILCOM '94, 2002The tuning speed of frequency synthesizers is usually specified by either phase or frequency setting. This paper shows that in frequency hopping systems (with FSK type of modulation) phase settling characteristics correspond to system performance better than frequency settling characteristics.
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PLL settling time: phase vs. frequency
Proceedings of TCC'94 - Tactical Communications Conference, 2002The tuning speed of frequency synthesizers is usually specified by either phase or frequency settling. The paper shows that in frequency hopping systems phase settling characteristics correspond to system performance better than frequency settling characteristics.
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A Fast-Settling Integer-$N$ Frequency Synthesizer Using Switched-Gain Control
IEEE Transactions on Circuits and Systems I: Regular Papers, 2020This paper presents a fully-integrated integer- $N$ frequency synthesizer that uses switched-gain control (SGC) within the phased-locked loop (PLL). Unlike other methods to improve PLL performance, the SGC method exploits the potential advantages of positive feedback within the main loop.
Haixiang Zhao, Soumyajit Mandal
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Time and Frequency Domain Evaluation of Settling Time in Repetitive Control
AIAA/AAS Astrodynamics Specialist Conference and Exhibit, 2008Repetitive control is a method that can cancel the vibrational disturbances to fine pointing equipment from slight imbalance in internal moving parts in spacecraft, such as momentum wheels, reaction wheels, or control moment gyros. The speed of convergence or the settling time of a repetitive control system can be of general interest in applications ...
Joe Yeol, Richard Longman
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Journal of Semiconductors, 2009
This paper proposes a fast-settling frequency-presetting PLL frequency synthesizer. A mixed-signal VCO and a digital processor are developed to accurately preset the frequency of VCO and greatly reduce the settling time. An auxiliary tuning loop is introduced in order to reduce reference spur caused by leakage current.
Yan Xiaozhou, Kuang Xiaofei, Wu Nanjian
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This paper proposes a fast-settling frequency-presetting PLL frequency synthesizer. A mixed-signal VCO and a digital processor are developed to accurately preset the frequency of VCO and greatly reduce the settling time. An auxiliary tuning loop is introduced in order to reduce reference spur caused by leakage current.
Yan Xiaozhou, Kuang Xiaofei, Wu Nanjian
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Feedforward Compensation by Specified Step Settling Considering Frequency Shaping of Control Input
IEEJ Transactions on Industry Applications, 2008AbstractThis paper presents a novel feedforward compensation for the fast and precise positioning control in mechatronic systems. The proposed compensator is designed considering the frequency shaping in control input to suppress the residual vibration, under the constraint of a specified number of steps in position reference.
Noriaki Hirose +3 more
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