The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform
P O Drawer - One of the best experts on this subject based on the ideXlab platform.
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Soil Water Measurement by Time Domain Reflectometry
Water, 2003Co-Authors: Steven R Evett, Soil Scientist, Terry A. Howell, P O DrawerAbstract:Time Domain Reflectometry (TDR) became known as a useful method for soil water content and bulk electrical conductivity measurement in the 1980s through the publication of a series of papers by Topp, Dalton and others. 15 Automated TDR systems for water content measurement have been described in Refs. 610. Commercial systems became available in the late 1980s and continue to evolve with TDR instruments, probes, and multiplexers (e.g., see Ref. 11) available from a few companies.
Steven R Evett - One of the best experts on this subject based on the ideXlab platform.
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Soil Water Measurement by Time Domain Reflectometry
Water, 2003Co-Authors: Steven R Evett, Soil Scientist, Terry A. Howell, P O DrawerAbstract:Time Domain Reflectometry (TDR) became known as a useful method for soil water content and bulk electrical conductivity measurement in the 1980s through the publication of a series of papers by Topp, Dalton and others. 15 Automated TDR systems for water content measurement have been described in Refs. 610. Commercial systems became available in the late 1980s and continue to evolve with TDR instruments, probes, and multiplexers (e.g., see Ref. 11) available from a few companies.
S. H. Xu - One of the best experts on this subject based on the ideXlab platform.
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New sensing mechanisms using an optical Time Domain Reflectometry with fiber Bragg gratings
Sensors & Actuators: A. Physical, 2007Co-Authors: Y. L. Lo, S. H. XuAbstract:A new optical Time Domain Reflectometry (OTDR) sensing mechanism combined with fiber Bragg gratings (FBGs) is presented. The intensity-based optical fiber sensor is implemented between a pair of FBGs in an OTDR system. Based on the ratio...
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New Sensing Mechanisms of an Optical Time Domain Reflectometry with Fiber Bragg Gratings
Optical Fiber Sensors, 2006Co-Authors: Y. L. Lo, S. H. XuAbstract:A new optical Time Domain Reflectometry (OTDR) sensing mechanism combined with fiber Bragg gratings (FBGs) is presented. The intensity-based optical fiber sensor is implemented between a pair of FBGs in an OTDR system.
Te Wen Pan - One of the best experts on this subject based on the ideXlab platform.
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Time-Domain Reflectometry using arbitrary incident waveforms
IEEE Transactions on Microwave Theory and Techniques, 2002Co-Authors: Te Wen Pan, Ching-wen Hsue, Jhin-fang HuangAbstract:A novel Time-Domain Reflectometry technique is developed for detecting the physical structures of transmission lines by using arbitrary waveforms. By discretizing both incident and reflected waves, we formulate the reflection coefficient of a nonuniform transmission line as a polynomial ratio in the Z-transform, wherein the numerator and denominator represent the reflected and incident waves, respectively. A reconstruction scheme is derived to obtain the characteristic impedance profile of a transmission line. Some examples are presented to illustrate the validity of this new technique.
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Reconstruction of nonuniform transmission lines from Time-Domain Reflectometry
IEEE Transactions on Microwave Theory and Techniques, 1997Co-Authors: Ching-wen Hsue, Te Wen PanAbstract:A novel technique is developed to reconstruct the physical structures of a nonuniform transmission line from its Time-Domain or frequency-Domain reflection (scattering) coefficient. This technique takes the past history of reflection processes of nonuniform line into considerations, and its accuracy exceeds that of a conventional Time-Domain Reflectometry (TDR) technique. Experimental results are presented to illustrate the validity of this reconstruction technique
Wei Wang - One of the best experts on this subject based on the ideXlab platform.
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Wavelength coded optical Time-Domain Reflectometry
Journal of Lightwave Technology, 2010Co-Authors: Ning Hua Zhu, Jian Guo Liu, Hong Guang Zhang, Ling Juan Zhao, Jian-hong Ke, Wei Chen, Wei WangAbstract:This paper presents a wavelength coded optical Time-Domain Reflectometry based on optical heterodyne technique. In this scheme, the probe and reference optical pulses have different wavelengths. This enables optical heterodyne detection to be used to improve the system performances significantly. We demonstrate a spatial resolution of 2.5 m within a range of 60 km in weak-reflection signal detection and direct observation of Brillouin scattering over a long optical fiber, suggesting online fiber sensing possible. The principle of wavelength coding is applicable to other systems like lidar and radar to increase receiver sensitivity and simplify system structure.
