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Xianhe Huang - One of the best experts on this subject based on the ideXlab platform.
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The prediction, simulation and verification of the Phase Noise in low-Phase-Noise crystal oscillator
2015 Joint Conference of the IEEE International Frequency Control Symposium & the European Frequency and Time Forum, 2015Co-Authors: Xianhe Huang, Junjie Jiao, Wei FuAbstract:In order to achieve the prediction of the Phase Noise of low Phase Noise crystal oscillator, based on the classic Phase Noise model of Leeson, the load Q value (QL) is calculated according to the selected oscillator circuit parameters. Thus, on the basis of Lesson Phase Noise formula, the predicted results of the Phase Noise of low Phase Noise crystal oscillators are obtained. Then, the nonlinear transistor model is constructed to simulate the Phase Noise of low Phase Noise crystal oscillator by using the ADS (Advanced Design System) simulation software of Agilent and obtain the simulated curve of the Phase Noise. At last, practical measurement has been performed on these low Phase Noise crystal oscillator prototypes. The measured results show that: the predicted Phase Noise of the oscillators and the ADS simulation results obtained by using nonlinear transistor model are both close to the actual measured Phase Noise, which are at 100Hz and far away offset the carrier frequency. After that, the existence of the deviation, which is near carrier frequency, is analyzed. The prediction and simulation methods given by this paper might be beneficial to simplify the design progress of the low Phase Noise crystal oscillator.
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Prediction, simulation, and verification of the Phase Noise in 80-MHz low-Phase-Noise crystal oscillators
IEEE transactions on ultrasonics ferroelectrics and frequency control, 2015Co-Authors: Xianhe Huang, Pingping Chen, Junjie JiaoAbstract:To predict the Phase Noise in an 80-MHz crystal oscillator, on the basis of the classical Leeson model, we analyzed and selected the oscillator Noise figure F and transistor corner frequency fc reasonably, and then calculated the loaded Q (QL) value of the oscillator according to the parameters in the selected Butler oscillation circuit. Thus, we obtained the predicted Phase Noise in an 80-MHz crystal oscillator according to the Leeson Phase Noise formula. Next, the simulation curve of the Phase Noise in this 80-MHz low-Phase-Noise crystal oscillator was obtained by establishing a transistor nonlinear model using commercial design software. Then, we debugged the 80-MHz low-Phase-Noise crystal oscillator prototype under the guidance of the prediction and simulation results and tested it. The measured results show that the Phase Noise predicted after selecting reasonable parameters for the Leeson model and the ADS simulation curve of the Phase Noise obtained by using the nonlinear transistor model are both close to the actual measured result. This result may be beneficial in simplifying the design process for low-Phase-Noise crystal oscillators.
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Analysis and design of low Phase Noise crystal oscillators
2012 IEEE International Conference on Mechatronics and Automation, 2012Co-Authors: Yan Wang, Xianhe HuangAbstract:The methods to reduce Phase Noise of crystal oscillators are presented and analyzed in the paper. According to analysis of Leeson formula, Phase Noise has a direct relation with Noise factor F, corner frequency f c and loaded quality factor Q L . Based on the method of reducing Phase Noise by improving Q L , the formula of Q L is derived by analysis of Pierce oscillator circuit and simulated by MATLAB. According to the simulation result, we can draw a conclusion that Q L is explicitly related to circuit parameters. Based on this conclusion, Phase Noise of a Pierce crystal oscillator is simulated and analyzed by the Agilent Advanced Design System. The simulated Phase Noise results are reduced by adjusting circuit parameter. A design of the prototype 120 MHz Pierce crystal oscillator is presented and the experiments are carried out. The measured near carrier frequency Phase Noise can achieve −100 dBc/Hz@10Hz and −132 dBc/Hz@100Hz. The simulated and experimental results show that it is feasible to design low Phase Noise crystal oscillator based on improving Q L .
Ali Hajimiri - One of the best experts on this subject based on the ideXlab platform.
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electronic laser Phase Noise reduction
Radio Frequency Integrated Circuits Symposium, 2013Co-Authors: Firooz Aflatouni, Behrooz Abiri, Angad Rekhi, Hooman Abediasl, Hossein Hashemi, Ali HajimiriAbstract:The first integrated wideband laser Phase Noise reduction scheme is presented where the laser Phase Noise is first detected using a photonic chip, processed using an electronic chip, and subtracted from the laser Phase in a feed-forward manner. The proof-of-concept experiments on a commercially available 1553nm distributed feedback laser show linewidth reduction from 6MHz to 250kHz equivalent to 14dB Phase Noise improvement. The hybrid integration of the photonic and electronic chips enables dramatic power consumption and area reduction compared to bench-top designs. This feed-forward scheme performs wideband Phase Noise reduction independent of the light source and, as such, it is compatible with several types of lasers.
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Phase Noise in distributed oscillators
Electronics Letters, 2002Co-Authors: C. J. White, Ali HajimiriAbstract:The Phase Noise of a distributed oscillator is evaluated very simply by identifying an effective capacitance equal to the total capacitance distributed along the transmission lines. The contributions of the various passive and active Noise sources to the total Phase Noise are calculated revealing several guidelines for improved distributed oscillator designs.
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Oscillator Phase Noise: a tutorial
IEEE Journal of Solid-State Circuits, 2000Co-Authors: Thomas H. Lee, Ali HajimiriAbstract:Linear time-invariant (LTI) Phase Noise theories provide important qualitative design insights but are limited in their quantitative predictive power. Part of the difficulty is that device Noise undergoes multiple frequency translations to become oscillator Phase Noise. A quantitative understanding of this process requires abandoning the principle of time invariance assumed in most older theories of Phase Noise. Fortunately, the Noise-to-Phase transfer function of oscillators is still linear, despite the existence of the nonlinearities necessary for amplitude stabilization. In addition to providing a quantitative reconciliation between theory and measurement, the time-varying Phase Noise model presented in this tutorial identifies the importance of symmetry in suppressing the upconversion of 1/f Noise into close-in Phase Noise, and provides an explicit appreciation of cyclostationary effects and AM-PM conversion. These insights allow a reinterpretation of why the Colpitts oscillator exhibits good performance, and suggest new oscillator topologies. Tuned LC and ring oscillator circuit examples are presented to reinforce the theoretical considerations developed. Simulation issues and the accommodation of amplitude Noise are considered in appendixes.
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Jitter and Phase Noise in ring oscillators
IEEE Journal of Solid-state Circuits, 1999Co-Authors: Ali Hajimiri, S. Limotyrakis, Thomas H. LeeAbstract:A companion analysis of clock jitter and Phase Noise of single-ended and differential ring oscillators is presented. The impulse sensitivity functions are used to derive expressions for the jitter and Phase Noise of ring oscillators. The effect of the number of stages, power dissipation, frequency of oscillation, and short-channel effects on the jitter and Phase Noise of ring oscillators is analyzed. Jitter and Phase Noise due to substrate and supply Noise is discussed, and the effect of symmetry on the upconversion of 1/f Noise is demonstrated. Several new design insights are given for low jitter/Phase-Noise design. Good agreement between theory and measurements is observed.
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Phase Noise in multi-gigahertz CMOS ring oscillators
Proceedings of the IEEE 1998 Custom Integrated Circuits Conference (Cat. No.98CH36143), 1998Co-Authors: Ali Hajimiri, S. Limotyrakis, Thomas H. LeeAbstract:An analysis of the Phase Noise in differential and single-ended ring oscillators using a time-variant model is presented. An expression for the RMS value of the impulse sensitivity function (ISF) is derived. A closed-form equation for Phase Noise of ring oscillators is calculated and a lower limit on the Phase Noise of ring oscillators is shown. Phase Noise measurements of oscillators running up to 5.5 GHz are in good agreement with the theory.
Thomas H. Lee - One of the best experts on this subject based on the ideXlab platform.
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Close-in Phase Noise in integrated oscillators
Noise in Communication, 2004Co-Authors: Reza Navid, Christoph Jungemann, Thomas H. Lee, Robert W. DuttonAbstract:Understanding the properties of close-in Phase Noise is crucial for analyzing the effects of low-frequency, colored Noise on the frequency stability of electrical oscillators. This paper shows these properties are distinctly different from those of far-out Phase Noise, which are commonly studied in the literature. Unlike far-out Phase Noise, the spectrum of close-in Phase Noise caused by several uncorrelated Noise sources is not the same as the sum of the Phase Noise spectra caused by individual sources. Furthermore, in the absence of colored Noise, this spectrum is not necessarily Lorentzian as generally believed. We show that the Phase Noise spectrum of a periodic signal with zero cycle-to-cycle jitter is always Lorentzian and demonstrate the appearance of 1/f 4 Phase Noise due to a Lorentzian Noise source. We also study two methods for suppressing the effects of low-frequency, colored Noise on Phase Noise: signal symmetrization and Noise-source switching. We show that the suppression of 1/f 3 Phase Noise in single-ended ring oscillators is due to switching and not because of symmetrization. Symmetrization is effective only for the Noise sources which are constantly “on”, such as the tail current source in differential ring oscillators. These findings provide effective guidelines for designing low-Phase-Noise oscillators.
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Close-in Phase Noise in electrical oscillators
2004Co-Authors: Reza Navid, Christoph Jungemann, Thomas H. Lee, Robert W. DuttonAbstract:Understanding the properties of close-in Phase Noise is crucial for analyzing the effects of low-frequency, colored Noise on the frequency stability of electrical oscillators. This paper shows these properties are distinctly different from those of far-out Phase Noise, which are commonly studied in the literature. Unlike far-out Phase Noise, the spectrum of close-in Phase Noise caused by several uncorrelated Noise sources is not the same as the sum of the Phase Noise spectra caused by individual sources. Furthermore, in the absence of colored Noise, this spectrum is not necessarily Lorentzian as generally believed. We show that the Phase Noise spectrum of a periodic signal with zero cycle-to-cycle jitter is always Lorentzian and demonstrate the appearance of 1/f 4 Phase Noise due to a Lorentzian Noise source. We also study two methods for suppressing the effects of low-frequency, colored Noise on Phase Noise: signal symmetrization and Noise-source switching. We show that the suppression of 1/f 3 Phase Noise in single-ended ring oscillators is due to switching and not because of symmetrization. Symmetrization is effective only for the Noise sources which are constantly on, such as the tail current source in differential ring oscillators. These findings provide effective guidelines for designing low-Phase-Noise oscillators.
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Oscillator Phase Noise: a tutorial
IEEE Journal of Solid-State Circuits, 2000Co-Authors: Thomas H. Lee, Ali HajimiriAbstract:Linear time-invariant (LTI) Phase Noise theories provide important qualitative design insights but are limited in their quantitative predictive power. Part of the difficulty is that device Noise undergoes multiple frequency translations to become oscillator Phase Noise. A quantitative understanding of this process requires abandoning the principle of time invariance assumed in most older theories of Phase Noise. Fortunately, the Noise-to-Phase transfer function of oscillators is still linear, despite the existence of the nonlinearities necessary for amplitude stabilization. In addition to providing a quantitative reconciliation between theory and measurement, the time-varying Phase Noise model presented in this tutorial identifies the importance of symmetry in suppressing the upconversion of 1/f Noise into close-in Phase Noise, and provides an explicit appreciation of cyclostationary effects and AM-PM conversion. These insights allow a reinterpretation of why the Colpitts oscillator exhibits good performance, and suggest new oscillator topologies. Tuned LC and ring oscillator circuit examples are presented to reinforce the theoretical considerations developed. Simulation issues and the accommodation of amplitude Noise are considered in appendixes.
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Jitter and Phase Noise in ring oscillators
IEEE Journal of Solid-state Circuits, 1999Co-Authors: Ali Hajimiri, S. Limotyrakis, Thomas H. LeeAbstract:A companion analysis of clock jitter and Phase Noise of single-ended and differential ring oscillators is presented. The impulse sensitivity functions are used to derive expressions for the jitter and Phase Noise of ring oscillators. The effect of the number of stages, power dissipation, frequency of oscillation, and short-channel effects on the jitter and Phase Noise of ring oscillators is analyzed. Jitter and Phase Noise due to substrate and supply Noise is discussed, and the effect of symmetry on the upconversion of 1/f Noise is demonstrated. Several new design insights are given for low jitter/Phase-Noise design. Good agreement between theory and measurements is observed.
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Phase Noise in multi-gigahertz CMOS ring oscillators
Proceedings of the IEEE 1998 Custom Integrated Circuits Conference (Cat. No.98CH36143), 1998Co-Authors: Ali Hajimiri, S. Limotyrakis, Thomas H. LeeAbstract:An analysis of the Phase Noise in differential and single-ended ring oscillators using a time-variant model is presented. An expression for the RMS value of the impulse sensitivity function (ISF) is derived. A closed-form equation for Phase Noise of ring oscillators is calculated and a lower limit on the Phase Noise of ring oscillators is shown. Phase Noise measurements of oscillators running up to 5.5 GHz are in good agreement with the theory.
Jing-heng Chen - One of the best experts on this subject based on the ideXlab platform.
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Suppression of Phase Noise induced by intrachannel four-wave mixing using Phase Noise averagers
2007 Conference on Lasers and Electro-Optics (CLEO), 2007Co-Authors: Chia-chien Wei, Jing-heng ChenAbstract:This work investigates a novel Phase Noise averagers to suppress IFWM-induced Phase Noise of RZ-DPSK signals. Both analytical and simulation results confirm that the IFWM-induced Phase Noise will be converged, even after an ultra-long transmission.
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Convergence of Phase Noise in DPSK transmission systems by novel Phase Noise averagers.
Optics express, 2006Co-Authors: Chia-chien Wei, Jing-heng ChenAbstract:This investigation proposes a novel all-optical Phase Noise averager to reduce residual Phase Noise in the differential Phase-shift keying (DPSK) transmission system with Phase-preserving amplitude regenerators. The proposed Phase Noise averager is based on a Phase-sensitive amplifier but does not require an extra Phase-locking optical pump beam. It can increase the correlation between the Phase Noises of neighboring bits and greatly reduce the differential Phase Noise in the transmission system. Independently of the cascaded spans, analytical analysis demonstrates that, in the DPSK system with repeated averagers, the total differential Phase Noise will be less than that before the first averager. Theoretical analysis and numerical simulation are carried out and confirm the significant improvement of DPSK signals using the proposed novel Phase Noise averagers.
Behzad Razavi - One of the best experts on this subject based on the ideXlab platform.
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relation between delay line Phase Noise and ring oscillator Phase Noise
IEEE Journal of Solid-state Circuits, 2014Co-Authors: Aliakbar Homayoun, Behzad RazaviAbstract:The Phase Noise of a ring oscillator can be obtained by multiplying its open-loop Phase Noise by a simple shaping function. The shaping function is computed using first principles and is applicable to both flicker-Noise-induced and white-Noise-induced Phase Noise, leading to compact equations for ring oscillators. It is also shown that flicker Noise upconversion in ring oscillators is primarily a function of the total gate capacitance and inevitable regardless of the risetime and falltime symmetry. Two oscillator prototypes fabricated in 65-nm CMOS technology verify the validity of the results.
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Analysis of Phase Noise in Phase/Frequency Detectors
IEEE Transactions on Circuits and Systems I: Regular Papers, 2013Co-Authors: Aliakbar Homayoun, Behzad RazaviAbstract:The Phase Noise of Phase/frequency detectors can significantly raise the in-band Phase Noise of frequency synthesizers, corrupting the modulated signal. This paper analyzes the Phase Noise mechanisms in CMOS Phase/frequency detectors and applies the results to two different topologies. It is shown that an octave increase in the input frequency raises the Phase Noise by 6 dB if flicker Noise is dominant and by 3 dB if white Noise is dominant. An optimization methodology is also proposed that lowers the Phase Noise by 4 to 8 dB for a given power consumption. Simulation and analytical results agree to within 3.1 dB for the two topologies at different frequencies.
