Flicker Noise Analysis on Chopper Amplifier

Author(s):  
Ting Zhou ◽  
Zhuo Gao ◽  
Jiajie Huang ◽  
Yewangqing Lu ◽  
Mingyi Chen ◽  
...  
2021 ◽  
pp. 247-253
Author(s):  
Jagritee Talukdar ◽  
G. Amarnath ◽  
Kavicharan Mummaneni

2014 ◽  
Vol 24 (01) ◽  
pp. 1550010 ◽  
Author(s):  
Jack Ou ◽  
Pietro M. Ferreira

We present an unified explanation of the transconductance-to-drain current (gm/ID)-based noise analysis in this paper. We show that both thermal noise coefficient (γ) and device noise corner frequency (f co ) are dependent on the gm/ID of a transistor. We derive expressions to demonstrate the relationship between the normalized noise power spectral density technique and the technique based on γ and f co . We conclude this letter with examples to demonstrate the practical implication of our study. Our results show that while both techniques discussed in this letter can be used to compute noise numerically, using γ and f co to separate thermal noise from flicker noise provides additional insight for optimizing noise.


2013 ◽  
Vol 592-593 ◽  
pp. 529-532
Author(s):  
Robert Macků ◽  
Pavel Koktavý ◽  
Tomas Trčka ◽  
Vladimir Holcman

This paper deals with excess noise sources in dielectric materials. We focus especially on the concrete samples that are frequently tested to ensure information about the reliability and level of degradation. Nevertheless, the testing methods are limited mainly by the proper contact creation, signal detection and noise defined sensitivity. Our efforts are directed to the noise properties assessment. It turns out that the Johnson-Nyquist noise and the 1/f (flicker) noise are generated in the different regions with the different response to the internal or external electric field. In addition the noise analysis is affected by the internal polarization phenomena and the material residual humidity. This issue in connection with the sample geometrical properties and the dielectric noise measurement methodology take part in this paper.


Author(s):  
Bachir Gourine ◽  
Sofiane Khelifa ◽  
Kamel Hasni ◽  
Farida Bachir Belmehdi

The objective of this work is to characterize the signals and noises of Geocenter variations time series obtained from different space geodesy techniques as Global Positioning System (GPS), Doppler Orbitography and Radiopositioning Integrated on Satellite (DORIS), and Satellite Laser Ranging (SLR). The proposed methodology is based on the estimation of periodic signals by performing frequency analysis using FAMOUS software (Frequency Analysis Mapping On Unusual Sampling) and evaluation of level and type of noises by Allan variance technique and Three Corned Hat (TCH) method. The available data concern 13 years (from 1993 to 2006) of weekly series of Geocenter residuals components and scale factor variations, according to ITRF2000. The results estimated are more accurate according to GPS and SLR of about 2-8 mm than DORIS of about 8-42 mm, for Geocenter. Better RMS of scale factor was obtained of about 0.1ppb (0.6mm) for GPS technique than SLR and DORIS with 0.6 and 0.9 ppb (3.6 and 5.4mm), respectively. The estimated seasonal signals amplitudes are in the range of few milimeters per technique with centimetre level for Z Geocenter component of DORIS. The Geocenter motion derived from SLR technique is more accurate and close to the geodynamic models. The noise analysis shows a dominant white noise in the   SLR and DORIS Geocenter solutions at a level of 0.6-1 mm and 10-40 mm, respectively. However, the GPS solution is characterized by a flicker noise at millimetre level, relating to mismodeling systematic errors.  


2021 ◽  
Vol 13 (3) ◽  
pp. 431
Author(s):  
Yuefan He ◽  
Guigen Nie ◽  
Shuguang Wu ◽  
Haiyang Li

The displacement of Global Navigation Satellite System (GNSS) station contains the information of surface elastic deformation caused by the variation of land water reserves. This paper selects the long-term coordinate series data of 671 International GNSS Service (IGS) reference stations distributed globally under the framework of World Geodetic System 1984 (WGS84) from 2000 to 2021. Different noise model combinations are used for noise analysis, and the optimal noise model for each station before and after hydrologic loading correction is calculated. The results show that the noise models of global IGS reference stations are diverse, and each component has different optimal noise model characteristics, mainly white noise + flicker noise (WN+FN), generalized Gauss–Markov noise (GGM) and white noise + power law noise (WN+PL). Through specific analysis between the optimal noise model and the time series velocity of the station, it is found that the maximum influence value of the vertical velocity can reach 1.8 mm when hydrological loading is considered. Different complex noise models also have a certain influence on the linear velocity and velocity uncertainty of the station. Among them, the influence of white noise + random walking noise is relatively obvious, and its maximum influence value in the elevation direction can reach over 2 mm/year. When studying the impact of hydrological loading correction on the periodicity of the coordinate series, it is concluded whether the hydrological loading is calculated or not, and the GNSS long-term coordinate series has obvious annual and semi-annual amplitude changes, which are most obvious in the vertical direction, up to 16.48 mm.


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