The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
Takahiro Ikui - One of the best experts on this subject based on the ideXlab platform.
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fiber bragg grating based single Axial Mode fabry perot interferometer and its strain and acceleration sensing applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry–Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of ϵ . Using a specially designed acceleration pick-up and a path-imbalance Mach–Zehnder interferometer for wavelength interrogation, a fully automatic SM-BFPI accelerometer, capable of giving ultrahigh performance, was developed. The performance of the accelerometer, with a very high sensitivity of 0.5 mGal in 0.1–200 Hz for 0−±980 Gal, is superior to that of electric servo-type accelerometer. To enable the accelerometer to exactly work in the field, the interrogator was stabilized against ambient temperature changes and mechanical disturbances by means of a compensation technique, using the constant wavelength of a reference SM-BFPI. In the course of the experimental study, particular attention has been paid to performance comparison with FBG sensors, much improvement against them having been demonstrated.
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Fiber-Bragg-Grating Based Single Axial Mode Fabry-Perot Interferometer and Its Strain and Acceleration Sensing Applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Daisuke Ota, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry-Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of
Toshihiko Yoshino - One of the best experts on this subject based on the ideXlab platform.
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fiber bragg grating based single Axial Mode fabry perot interferometer and its strain and acceleration sensing applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry–Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of ϵ . Using a specially designed acceleration pick-up and a path-imbalance Mach–Zehnder interferometer for wavelength interrogation, a fully automatic SM-BFPI accelerometer, capable of giving ultrahigh performance, was developed. The performance of the accelerometer, with a very high sensitivity of 0.5 mGal in 0.1–200 Hz for 0−±980 Gal, is superior to that of electric servo-type accelerometer. To enable the accelerometer to exactly work in the field, the interrogator was stabilized against ambient temperature changes and mechanical disturbances by means of a compensation technique, using the constant wavelength of a reference SM-BFPI. In the course of the experimental study, particular attention has been paid to performance comparison with FBG sensors, much improvement against them having been demonstrated.
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Fiber-Bragg-Grating Based Single Axial Mode Fabry-Perot Interferometer and Its Strain and Acceleration Sensing Applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Daisuke Ota, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry-Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of
Yasukazu Sano - One of the best experts on this subject based on the ideXlab platform.
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fiber bragg grating based single Axial Mode fabry perot interferometer and its strain and acceleration sensing applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry–Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of ϵ . Using a specially designed acceleration pick-up and a path-imbalance Mach–Zehnder interferometer for wavelength interrogation, a fully automatic SM-BFPI accelerometer, capable of giving ultrahigh performance, was developed. The performance of the accelerometer, with a very high sensitivity of 0.5 mGal in 0.1–200 Hz for 0−±980 Gal, is superior to that of electric servo-type accelerometer. To enable the accelerometer to exactly work in the field, the interrogator was stabilized against ambient temperature changes and mechanical disturbances by means of a compensation technique, using the constant wavelength of a reference SM-BFPI. In the course of the experimental study, particular attention has been paid to performance comparison with FBG sensors, much improvement against them having been demonstrated.
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Fiber-Bragg-Grating Based Single Axial Mode Fabry-Perot Interferometer and Its Strain and Acceleration Sensing Applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Daisuke Ota, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry-Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of
Keiichi Fujita - One of the best experts on this subject based on the ideXlab platform.
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fiber bragg grating based single Axial Mode fabry perot interferometer and its strain and acceleration sensing applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry–Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of ϵ . Using a specially designed acceleration pick-up and a path-imbalance Mach–Zehnder interferometer for wavelength interrogation, a fully automatic SM-BFPI accelerometer, capable of giving ultrahigh performance, was developed. The performance of the accelerometer, with a very high sensitivity of 0.5 mGal in 0.1–200 Hz for 0−±980 Gal, is superior to that of electric servo-type accelerometer. To enable the accelerometer to exactly work in the field, the interrogator was stabilized against ambient temperature changes and mechanical disturbances by means of a compensation technique, using the constant wavelength of a reference SM-BFPI. In the course of the experimental study, particular attention has been paid to performance comparison with FBG sensors, much improvement against them having been demonstrated.
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Fiber-Bragg-Grating Based Single Axial Mode Fabry-Perot Interferometer and Its Strain and Acceleration Sensing Applications
Journal of Lightwave Technology, 2016Co-Authors: Toshihiko Yoshino, Yasukazu Sano, Daisuke Ota, Keiichi Fujita, Takahiro IkuiAbstract:Based on a rigorous Mode theory and considering the wavelength dispersion of fiber Bragg grating (FBG), the conditions necessary for FBG-based Fabry-Perot interferometer (BFPI) to operate in single Axial Mode (SM) were investigated, as an extension of phase-shifted FBG, by analytical formulas and numerical simulation. Following the theoretical results, SM-BFPI of very narrow bandpass was designed and fabricated. Using that, the first of its kind to our knowledge, SM-BFPI-based WDM distributed (four-points) strain sensing was demonstrated which had a point-like ultrahigh spatial resolution of 2.1 mm and very high strain precision of
E K N Yung - One of the best experts on this subject based on the ideXlab platform.
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Axial Mode elliptical helical antenna with parasitic wire for cp bandwidth enhancement
Iet Microwaves Antennas & Propagation, 2007Co-Authors: Zehai Wu, Bing Fu, E K N YungAbstract:Elliptical helical antenna using parasitic helix to enhance the Axial ratio (AR) bandwidth is presented. The parasitic wire increases the AR bandwidth (AR < 3 dB) from 13.6 to 25%, and enhances the directivity by 2 dB in the frequency band interested, while maintaining the simple single feeding system. The simulated results and experimental results including AR, impedance and radiation patterns are given, and some good agreements are observed.
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Axial Mode helix antenna with exponential spacing
Microwave and Optical Technology Letters, 2007Co-Authors: Canhui Chen, E K N Yung, Binjie HuAbstract:A novel wideband CP helix antenna with exponential spacing is presented in this paper. Since traveling wave current over a wide range of frequencies has been excited, it possesses better performance. Both numerical results and experimental results show that the Axial ratio bandwidth of the exponential spacing helix (ESH) antenna is 58.6% greater than that of the linear spacing helix (LSH) antenna in the same conditions. The characteristics of impedance, power gains, and radiation patterns for the ESH antenna are also investigated and compared with LSH antenna. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1525–1530, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22485
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Axial Mode elliptical cross section helical antenna
Microwave and Optical Technology Letters, 2006Co-Authors: Zehai Wu, E K N YungAbstract:This article gives an experimental study of the elliptical helical antenna with circular polarization characteristics. It is observed that the Axial ratio bandwidth of the elliptical helix remains stable when the eccentricity of the ellipse is low (below 0.77), and when the cross section approaches more prolate, the AR bandwidth becomes smaller with the increment of the ellipse eccentricity. The variety trends of the AR and HPBW are shown and radiation patterns of elliptical helix with eccentricity 0.89 have been given. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2080–2083, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21878
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accordion shape monofilar Axial Mode helix for rfid reader
Electronics Letters, 2006Co-Authors: Hang Wong, E K N YungAbstract:An accordion shape monofilar Axial Mode helical antenna designed by curving the helix along the axis is proposed. This antenna achieves a low-profile characteristic as the 10-turn helix's Axial length is 0.354/spl lambda/. The impedance bandwidth (SWR<1.5) is 9% from the frequency of 880 to 963 MHz and the Axial ratio bandwidth (AR<3 dB) is 6.5%. The measured gain is 10.2 dBi. This antenna operated at the centre frequency of 915 MHz and has a tilted radiation of 17/spl deg/ to the curving side.
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coAxial feed Axial Mode hemispherical helical antenna
Electronics Letters, 1999Co-Authors: Kafai Chan, E K N Yung, X Q ShingAbstract:A coAxial-feed Axial Mode hemispherical helical antenna is studied experimentally and theoretically. Results for a 3-turn hemispherical helix indicate that circular polarisation can be obtained over a broad beamwidth. The gain bandwidth is ~33% and the peak gain is 7.6 dB. The input impedance shows that it is a standing wave antenna
