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Sensitivity Analysis of S-Parameter Measurements Due to Nonideal SOLR calibration Standards

IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT 2021年 70卷 1-10页

作者： Zhao, Wei Cheng, Chunyue Li, Lin Xidian Univ Key Lab Elect Equipment Struct Design Minist Educ Xian 710071 Peoples R China Beijing Inst Radio Metrol & Measurement Sci & Technol Metrol & Calibrat Lab Beijing 100854 Peoples R China Chinese Acad Sci Shanghai Inst Opt & Fine Mech Key Lab Quantum Opt Shanghai 201800 Peoples R China

In this article, with the reformulation of short-openload-reciprocal (SOLR), the influence of nonideal standards on S-parameter uncertainties is investigated by two different methods. The SOLR calibration algorithm is reformulated by our recently proposed theory, which helps to simplify the mathematical derivation. Then, based on the uncalibration model, the one-step and two-step methods are developed for the sensitivity analysis of SOLR. These two methods come from different theories that were originally developed for SOLT and TRL, respectively. Finally, the analytical expressions of the sensitivity coefficients are derived, and the results obtained from these two methods are proved to be just opposite in sign.

关键词： calibration algorithm measurement uncertainty microwave measurement sensitivity analysis short-open-load-reciprocal (SOLR) vector network analyzer (VNA)

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Dither-based calibration of bit weights in pipelined-SAR ADCs with fast convergence speed using partially split structure

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ELECTRONICS LETTERS 2020年第18期56卷 916-+页

作者： Sun, Jie Li, Xin Yan, Chenggang Liu, Weiqiang Nanjing Univ Aeronaut & Astronaut Nanjing Peoples R China Southeast Univ Natl ASIC Syst Engn Res Ctr Nanjing Peoples R China

A background calibration technique is proposed to correct bit weights in pipelined-successive-approximation-register (SAR) analogue-to-digital converters (ADCs). By splitting the second stage, the input signal interference is mostly removed, thereby greatly enhancing the convergence speed of the algorithm. Besides, the dither signal assists to eliminate mismatch issues between the partially split ADCs, thus relaxing the analogue overheads. According to the simulation, after calibration, the spurious-free-dynamic-range and signal-to-noise-and-distortion-ratio are improved from 53.2 to 88.2 dB and 49.5 to 75.2 dB, respectively. The calibration algorithm converges with about only 600 K samples.

关键词： calibration analogue-digital conversion signal-to-noise-and-distortion-ratio calibration algorithm pipelined-SAR ADC fast convergence speed partially split structure background calibration technique pipelined-successive-approximation-register analogue-to-digital converters input signal interference dither signal analogue overheads spurious-free-dynamic-range partially split ADC dither-based calibration bit weight correction mismatch elimination

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High-accuracy online calibration system for electronic voltage transformers with digital output

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TRANSACTIONS OF THE INSTITUTE OF MEASUREMENT AND CONTROL 2014年第6期36卷 734-742页

作者： Li, Zhenhua Li, Hongbin Zhang, Zhi Luo, Pandian Li, Hongfeng Zhang, Wenlu SEEE Huazhong Univ Sci & Technol Wuhan 430074 Peoples R China State Key Lab Adv Elect Engn & Technol Wuhan Peoples R China

The accuracy and stability of electronic transformers (ETs) is the guarantee of the safe and reliable operation of a power system. As an emerging technology, however, the ETs' failure rate is higher than that of traditional transformers. As a result, the calibration period should be shortened. Existing calibration methods address the verification on condition that the ETs and lines are powered off, which has a long calibration period and results in a power-off loss. As a result, an online calibration system for electronic voltage transformers (EVTs) is proposed in this paper. Employing a specially designed standard voltage online measuring unit, the proposed system can obtain the high voltage signals without powering off and do the calibration when the EVTs are working. The power-off loss can be avoided, and problems of the running EVTs can be detected in time. The main factors influencing the system accuracy are addressed. The system has been validated by the Quality Inspection and Testing Center of the China Electric Power Research Institute, and field tests have been conducted in Guizhou Electric Power Company. The results show that the proposed system has good reliability and can reach an accuracy class of 0.05 in complicated electromagnetic circumstances.

关键词： calibration algorithm digital output online calibration synchronization voltage transformer

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Second- and third-order multivariate calibration:: Data, algorithms and applications

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TRAC-TRENDS IN ANALYTICAL CHEMISTRY 2007年第7期26卷 752-765页

作者： Escandar, Graciela M. Faber, Nicholaas (Klaas) M. Goicoechea, Hector C. Munoz de la Pena, Arsenio Olivieri, Alejandro C. Poppi, Ronei J. Univ Nacl Rosario Fac Ciencias Bioquim & Farmaceut Dept Quim Analit Rosario Argentina Chemometry Consultancy NL-6717 VD Ede Netherlands Univ Nacl Litoral Fac Bioquim & Ciencias Biol Catedra Quim Analit 1 LADAQ RA-S3000ZAA Santa Fe Argentina Univ Extremadura Fac Ciencias Dept Quim Analit E-06071 Badajoz Spain Univ Estadual Campinas Inst Quim BR-13083970 Campinas SP Brazil

We review second- and third-order multivariate calibration, based on the growing literature in this field, the variety of data being produced by modern instruments, and the proliferation of algorithms capable of dealing with higher-order data. We primarily emphasize the relevance of the subject to analytical chemistry. We intend, in the terminology section, to clarify some confusing features relating to the definition of sample constituents in second-order calibration. We then classify and compare instrumental data and available algorithms. We provide insight into the relative advantages and disadvantages of the existing algorithms (e.g., in terms of: achieving second-order advantage (the ability to cope with varying amounts of potential interferents in test samples), presence of linear dependency in the data, handling trilinear deviations, using incomplete calibration data, extension to higherorder information, handling missing values;and, providing physico-chemical information. Finally, we present a number of applications, selected from recent second- and third-order experimental works based on data obtained through excitation-emission fluorescence spectroscopy, spectral-kinetic and spectral-pH measurements, and hyphenated techniques. (c) 2007 Elsevier Ltd. All rights reserved.

关键词： calibration algorithm excitation-emission fluorescence spectroscopy hyphenated technique multivariate calibration second-order data spectral-kinetic data spectral-pH data third-order data

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Effective mutual coupling estimation and calibration for conformal arrays based on pattern perturbation

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IET MICROWAVES ANTENNAS & PROPAGATION 2020年第15期14卷 1998-2006页

作者： Zhang, Xiaowen Liao, Guisheng Yang, Zhiwei Zou, Xintong Chen, Ying Xidian Univ Natl Lab Radar Signal Proc Xian 710071 Peoples R China Xidian Univ Collaborat Innovat Ctr Informat Sensing & Underst Xian 710071 Peoples R China Xidian Univ Key Lab Antennas & Microwave Technol Xian 710071 Peoples R China

Processing conformal array signal is sensitive to antenna patterns on horizontal (H) and vertical (V ) planes while mutual coupling (MC) impacts distinctly on them. Many existing MC calibration algorithms ignore that and thus lose their efficacy. In this study, MC is modelled as distortions of H and V patterns. The direction-dependent and slowly varied properties indicate that MC can be estimated via sampling in the interested spatial range and calibrated. A novel MC estimation and calibration algorithm for all kinds of conformal arrays is proposed based on it. The process requires the use of three signals with diverse sets of polarisation emitted by a known calibrated source in each sampling direction. The selection of diverse polarisations is analysed in terms of optimisation and practical application. Simulations exhibit the potentialities of the proposed algorithm regarding the precision of MC estimation and the efficiency of calibration. It shows that significant superiority influences greatly in the analysis of conformal arrays.

关键词： conformal antennas array signal processing calibration antenna radiation patterns antenna arrays antenna patterns mutual coupling estimation direction-dependent properties slowly varied properties spatial range MC estimation calibration algorithm conformal arrays known calibrated source sampling direction pattern perturbation MC calibration algorithms conformal array signal processing

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Sensor-array calibration using a maximum-likelihood approach

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 1996年第6期44卷 827-835页

作者： Ng, BC Samson, CM DEF SCI ORG SINGAPORE 0511 SINGAPORE

High-resolution array processing algorithms for source localization are known to be sensitive to errors in the model for the sensor-array spatial response. In particular, unknown gain, phase, and mutual coupling as well as errors in the sensor positions can seriously degrade the performances of array-processing algorithms. This paper describes a calibration algorithm that estimates the calibration matrix consisting of the unknown gain, phase, and mutual-coupling coefficients as well as the sensor positions using a set of calibration sources in known locations. The estimation of the various parameters is based on a maximum likelihood approach. Cramer-Rao lower-bound (CRB) expressions for the sensor positions and the calibration matrix parameters are also derived. Numerical results are shown to illustrate the potential usefulness of the proposed calibration algorithm toward better accuracy and resolution in parametric array-processing algorithms.

关键词： calibration direction-of-arrival estimation error analysis matrix algebra maximum likelihood estimation measurement errors signal resolution Cramer-Rao lower bound DOA estimation accuracy calibration algorithm calibration matrix estimation calibration ma matrix algebra sensor placement calibration Error analysis Position measurement signal resolution Error measure maximum likelihood algorithms Sensors Direction of arrival estimation maximum likelihood estimation

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A novel kinematic calibration method for a 3DOF flexure-based parallel mechanism

A novel kinematic calibration method for a 3DOF flexure-base...

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IEEE/RSJ International Conference on Intelligent Robots and Systems

作者： Chao, Daihong Zong, Guanghua Liu, Rong Yu, Jingjun Beihang Univ Sch Mech Engn & Automat Beijing Peoples R China

ISBN: (纸本)9781424402588

This paper presents a novel calibration strategy for a 3DOF flexure-based parallel manipulator to overcome weaknesses and embrace merits of existing approaches. An algorithm so called Simplex Method is developed for the purpose of calibrating this manipulator by means of a camera-based data acquisition system. calibration is performed according to the inverse kinematic model method. The Simplex Method algorithm doesn't identify directly the errors of geometry parameters, but finds the most appropriate control model taking all the errors into account, thus can improve the moving accuracy of the end-effector sharply. In the calibration process, matrix regrouping method is introduced to obtain the most appropriate control model. After getting the control model experimentally, verification experiments utilizing a laser interferometer have also been conducted to prove the effectiveness of this novel calibration method.

关键词： flexure parallel mechanism calibration algorithm Simplex Method vision system

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A High Accuracy Signal Conditioning Method and Sensor calibration System for Wireless Sensor in Automotive Tire Pressure Monitoring System

A High Accuracy Signal Conditioning Method and Sensor Calibr...

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3rd International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM 2007)

作者： Leng, Yi Zhao, Genbao Li, Qingxia Sun, Chunyu Liu, Sheng Huazhong Univ Sci & Technol Dept Elect & Informat Wuhan 430074 Peoples R China Chery Automobile Co Ltd CERI Elect & Elect Dept Wuhan 241009 Peoples R China Shanghai FineMEMS Inc Shanghai 201203 Peoples R China AFRA Wuhan 430019 Peoples R China

ISBN: (纸本)9781424413119

Tire Pressure Monitoring System (TPMS) is used to detect when one or more of the vehicle's tires is 25 percent or more below the manufacturer's recommended inflation pressure. A TPMS system consists of four wireless sensors, a high frequency (HF) antenna and a central receiver. In this paper, a high accuracy sensor incorporated with a sensor signal conditioning chip is presented. A new TPMS wireless signal conditioning method for automotive applications is developed. The signal conditioning method consists of a signal conditioning chip and a calibration algorithm. The calibration algorithm has been established by relating to measured voltage, temperature and pressure ADC reading at three different temperature ranges. Twenty-five relating coefficients are obtained from characterization test before sensor signal conditioning is applied to TPMS wireless sensor calibration. The test results show that the signal conditioning method provides higher accuracy performance for wireless sensor within a battery supply voltage range from 2.1V to 3.6 V and a temperature range from -40 degrees C to 125 degrees C. The signal conditioning method also reduces the cost of wireless sensor. Moreover, a presented sensor calibration system helps to improve production efficiency and lower production costs.

关键词： wireless sensor pressure sensor signal conditioning calibration algorithm sensor calibration system

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An Optical based Non-Contact Five-Axis Machine Tool calibration IOT System 5

An Optical based Non-Contact Five-Axis Machine Tool Calibrat...

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IEEE International Conference on Consumer Electronics-Taiwan (ICCE-TW)

作者： Lu, Pin-Wei Sun, Chi-Chia Hsu, Chia-Ming Lin, Hon-En Natl Formosa Univ Dept Elect Engn Huwei Township Yunlin County Taiwan Natl Formosa Univ Precis Machine Ctr Huwei Township Yunlin County Taiwan

ISBN: (纸本)9781538663011

Cutting tool machining quality and accuracy calibration has always been an important indicator of the performance of machine tools, machine tool testing technology is particularly the key point. In this paper, an optical based non-contact five-axis machine tool calibration system with IOT feature is presented. It can be obtained once the three-dimensional detection signals, combined with embedded systems for data calculation and communication using Wi-Fi wireless. Test hardware includes two sets of laser light source, two sets of photoelectric sensors and spherical lens and DSP processor. The proposed calibration IOT system has simple for setup, low cost, high precision features for calibration five-axis motor and static error.

关键词： Five-Axis Cutting Tool Machine calibration algorithm IOT Sensor Non-Contact

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Consideration of Environmental and Functional Factors in calibration of Antenna Integrated Active Phased Array Transmitters

Consideration of Environmental and Functional Factors in Cal...

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IEEE International Symposium on Phased Array Systems and Technology (PAST)

作者： Temir, Kaan Akyuz, Murat Sencer Alp, Yasar Kemal Aselsan AS Phased Array Technol Dept Ankara Turkey

ISBN: (纸本)9781509014477

When dealing with direct calibration in phased array systems, in which power amplifier (PA) output for each antenna element is measured with respect to all phase and amplitude levels, several issues complicate the calibration algorithm and extend calibration time, such as wide frequency band, large element number, temperature changes, driving power of PAs. In this work, all realizable aspects effecting direct calibration of multi-octave band phased array system with 100+ elements are examined and a robust and consistent algorithm is developed and applied.

关键词： phased array calibration phase error amplitude error calibration algorithm Monte-Carlo analysis

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