Limitations on Threshold Sensitivity and Measurement Errors in Pulsed Optical Fiber Accelerometers

1998 ◽  
Vol 52 (12) ◽  
pp. 49-51
Author(s):  
P. A. Dem'yanenko
Keyword(s):  
Optical Fiber ◽  
Measurement Errors ◽  
Threshold Sensitivity

The Study and Applications on Fiber Bragg Grating (FBG) Monitoring System for Deep and Large Deformed Soft Ground

2011 ◽  
Vol 261-263 ◽  
pp. 1341-1347
Author(s):  
Hong Zhang ◽  
You Ping Liu ◽  
Jian Hua Li ◽  
Mao Dong Xiong
Keyword(s):  
Optical Fiber ◽  
Fiber Bragg Grating ◽  
Long Range ◽  
Measurement Errors ◽  
Fiber Optic Sensor ◽  
Displacement Sensor ◽  
Bragg Grating ◽  
Soft Ground ◽  
Ground Settlement ◽  
Current Monitoring

The fiber Bragg grating (FBG) technology is studied based on the current monitoring status of the highway soft ground settlement, for instance, the low degree of automation, the unsatisfied accuracy of the device, the slow data transmission and the greater measurement errors. The limited measuring range and the difficult situations of the soft ground burying and installing of the fiber optic sensor still need to be addressed. This thesis has analyzed the development of the long range optical fiber displacement sensor as well as its burying techniques which are suitable for soft ground settlement monitoring. Both of them have been successfully applied to De Chang Highway D10 subject. The study also shows that the long range optical fiber displacement sensor is able to meet the requirements of the soft ground monitoring. And data can be accurately monitored by means of real-time or on-line continuously. This is of great significance in pushing forward the development of the fiber optical monitoring technology in the field.

scholarly journals ANALISIS PERFORMANCE SERAT OPTIK SEBAGAI MEDIA TRANSMISI PADA JALUR TRANSMISI LUBUK BASUNG–LUBUK SIKAPING

2018 ◽  
Vol 2 (2) ◽  
Author(s):  
Riri Yulianti Solfia ◽  
Putra Jaya ◽  
Yasdinul Huda
Keyword(s):  
Optical Fiber ◽  
Key Words ◽  
Measured Data ◽  
Threshold Sensitivity ◽  
Maximum Value ◽  
Measurement Results ◽  
Link Budget ◽  
Attenuation Values ◽  
Instrument Sensitivity

This study aims to investigate the performance of optical fiber as a transmission medium. This was conducted using the discrepancy modle, which made the comparison between the measured data with the standard used PT.Telkom and ITU-T. Object of this research is the value of attenuation and power link budget. Based on the measured data on each core is core 3,7,9,10,12,15,18,20, and 23 obtained the following values as 0.239 dB / km, 0.238 dB / km, 0.240 dB / km, 0.239 dB / km , 0.236 dB / km, 0.240 dB / km, 0.242 dB / km, 0.233 dB / km, 0.238 dB / km, and the results of calculations on the same cores with each core attenuation is 0.235 dB / km, 0.235 dB / km, 0.235 dB / km, 0.235 dB / km, 0.235 dB / km, 0.235 dB / km, 0.237  dB  /  km,  0.235  dB  /  km,  0.235  dB  /  km,  based  on  the  results  of  calculation, measurement and compared with standard attenuation values are in compliance with standards ITU-T and PT.Telkom because it does not exceed the maximum attenuation is 0.25 dB/km. Analysis performed with comparing the power in receive (Rx) between the results of the calculation of each core with measurement results and instrument sensitivity, but the overall results  of  the  calculation  and  measurement  is  still  at  the  maximum  value  of  threshold sensitivity system is -19 dBm. Key   words :  Core,   Performance,   Attenuation,   Power   Link   Budget,   Rx   Levell

scholarly journals Testing of a Polarimetric Current Sensor in the Frequency Domain

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3008
Author(s):  
Sławomir Andrzej Torbus ◽  
Jacek Andrzej Michalski
Keyword(s):  
Optical Fiber ◽  
Optical Fibers ◽  
Measurement Errors ◽  
Scientific Research ◽  
Single Mode ◽  
Market Potential ◽  
Current Sensor ◽  
Industrial Property ◽  
Measuring Coil ◽  
The Impact

This paper proposes an original model of a polarimetric current sensor, in which the measuring coil was made of a single mode telecommunication optical fiber ITU-T G.652, G.653, G.655, and G.657. This sensor was subjected to the commercialization process, which was carried out by a company combining the functionality of a technology transfer center with the capabilities of the Startit Fund Sp. z o.o. The published results included the analysis of the implementation readiness, the analysis of the market potential, the valuation of the industrial property rights of the invention and indicated further directions of scientific research on the sensor, which include the frequency analysis of measurement signals. This prompted the conduct of relevant scientific research. In this paper, the idea of measurement of current using polarimetric current sensor with optical fiber coil has been briefly characterized. It shows the definition and basic properties of the Discrete Fourier Transform (DFT). It discusses the technique of determining the value of each harmonic of signal at the input and output of polarimetric current sensor. The value of measurement errors and total harmonic distortion (THD) have been calculated. The general conclusions for disturbances in the processing realized in polarimetric current sensor have been formulated. In addition, the impact of the molar concentration of the dopant GeO2 in the core of the single mode telecommunication optical fibers and the impact of the number of turns of the measuring coil on the distortion accompanying the process of processing have been determined. Therefore, it can be concluded that the key result obtained during the research is the confirmation of the fact that single mode telecommunication optical fibers can be used to build the measuring coil of a polarimetric sensor used for measuring alternating currents. This means that the considered sensor, when measuring this type of currents, does not introduce additional distortions and distortions of their waveforms.

scholarly journals Ошибки измерений интерферометров с дифракционной волной сравнения

2019 ◽  
Vol 89 (11) ◽  
pp. 1789
Author(s):  
А.А. Ахсахалян ◽  
Д.А. Гаврилин ◽  
И.В. Малышев ◽  
Н.Н. Салащенко ◽  
М.Н. Торопов ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Measurement Errors ◽  
Measurement Accuracy ◽  
Spherical Wave ◽  
Single Mode ◽  
Recording System ◽  
Reference Wave ◽  
Single Mode Optical Fiber ◽  
Experimental Stand ◽  
Optical Part

The paper describes the experimental stand and the results of studies of aberrations of the sources of a reference spherical wave (SRSW) based on a single-mode optical fiber with a sub-wave output aperture using the optical part of the recording system (OPRS). SRSW and OPRS are being developed for a referenceless interferometer with a diffraction reference wave. The technique to minimize measurement errors is described. Developed SRSW and OPRS provide subnanometer optics measurement accuracy. The possibilities of improving the accuracy of interferometer measurements to the picometer level are discussed.

Precise on-line Measurement of Lattice Vectors

1990 ◽  
Vol 48 (1) ◽  
pp. 530-531
Author(s):  
W.J. de Ruijter ◽  
Sharma Renu
Keyword(s):  
Electron Microscope ◽  
Measurement Errors ◽  
Dynamic Range ◽  
Structural Information ◽  
Statistical Parameter ◽  
Systematic Errors ◽  
Geometric Distortion ◽  
Crystal Silicon ◽  
Camera System ◽  
On Line

Established methods for measurement of lattice spacings and angles of crystalline materials include x-ray diffraction, microdiffraction and HREM imaging. Structural information from HREM images is normally obtained off-line with the traveling table microscope or by the optical diffractogram technique. We present a new method for precise measurement of lattice vectors from HREM images using an on-line computer connected to the electron microscope. It has already been established that an image of crystalline material can be represented by a finite number of sinusoids. The amplitude and the phase of these sinusoids are affected by the microscope transfer characteristics, which are strongly influenced by the settings of defocus, astigmatism and beam alignment. However, the frequency of each sinusoid is solely a function of overall magnification and periodicities present in the specimen. After proper calibration of the overall magnification, lattice vectors can be measured unambiguously from HREM images.Measurement of lattice vectors is a statistical parameter estimation problem which is similar to amplitude, phase and frequency estimation of sinusoids in 1-dimensional signals as encountered, for example, in radar, sonar and telecommunications. It is important to properly model the observations, the systematic errors and the non-systematic errors. The observations are modelled as a sum of (2-dimensional) sinusoids. In the present study the components of the frequency vector of the sinusoids are the only parameters of interest. Non-systematic errors in recorded electron images are described as white Gaussian noise. The most important systematic error is geometric distortion. Lattice vectors are measured using a two step procedure. First a coarse search is obtained using a Fast Fourier Transform on an image section of interest. Prior to Fourier transformation the image section is multiplied with a window, which gradually falls off to zero at the edges. The user indicates interactively the periodicities of interest by selecting spots in the digital diffractogram. A fine search for each selected frequency is implemented using a bilinear interpolation, which is dependent on the window function. It is possible to refine the estimation even further using a non-linear least squares estimation. The first two steps provide the proper starting values for the numerical minimization (e.g. Gauss-Newton). This third step increases the precision with 30% to the highest theoretically attainable (Cramer and Rao Lower Bound). In the present studies we use a Gatan 622 TV camera attached to the JEM 4000EX electron microscope. Image analysis is implemented on a Micro VAX II computer equipped with a powerful array processor and real time image processing hardware. The typical precision, as defined by the standard deviation of the distribution of measurement errors, is found to be <0.003Å measured on single crystal silicon and <0.02Å measured on small (10-30Å) specimen areas. These values are ×10 times larger than predicted by theory. Furthermore, the measured precision is observed to be independent on signal-to-noise ratio (determined by the number of averaged TV frames). Obviously, the precision is restricted by geometric distortion mainly caused by the TV camera. For this reason, we are replacing the Gatan 622 TV camera with a modern high-grade CCD-based camera system. Such a system not only has negligible geometric distortion, but also high dynamic range (>10,000) and high resolution (1024x1024 pixels). The geometric distortion of the projector lenses can be measured, and corrected through re-sampling of the digitized image.

Bending loss formulas for step-index optical fiber and their applicable regions

1981 ◽  
Vol 64 (10) ◽  
pp. 95-103
Author(s):  
Kiyonobu Kusano ◽  
Shigeo Nishida
Keyword(s):  
Optical Fiber ◽  
Step Index ◽  
Bending Loss

Development of reference materials with the composition of propyl and isopropyl alcohol solutions

2020 ◽  
pp. 66-72
Author(s):  
Irina A. Piterskikh ◽  
Svetlana V. Vikhrova ◽  
Nina G. Kovaleva ◽  
Tatyana O. Barynskaya
Keyword(s):  
Reference Materials ◽  
Measurement Errors ◽  
Isopropyl Alcohol ◽  
Certified Reference Materials ◽  
Toxic Substances ◽  
Biological Objects ◽  
Margin Of Error ◽  
Measurement Results ◽  
And Control ◽  
Characteristic Mass

Certified reference materials (CRM) composed of propyl (11383-2019) and isopropyl (11384-2019) alcohols solutions were created for validation of measurement procedures and control of measurement errors of measurement results of mass concentrations of toxic substances (alcohol) in biological objects (urine, blood) and water. Two ways of establishing the value of the certified characteristic – mass consentration of propanol-1 or propanol-2 have been studied. The results obtained by the preparation procedure and comparison with the standard are the same within the margin of error.

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