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PARAFAC Decomposition for Ultrasonic Wave Sensing of Fiber Bragg Grating Sensors: Procedure and Evaluation.

Zheng R, Nakano K, Ohashi R, Okabe Y, Shimazaki M, Nakamura H, Wu Q - Sensors (Basel) (2015)

Bottom Line: Ultrasonic wave-sensing technology has been applied for the health monitoring of composite structures, using normal fiber Bragg grating (FBG) sensors with a high-speed wavelength interrogation system of arrayed waveguide grating (AWG) filters; however, researchers are required to average thousands of repeated measurements to distinguish significant signals.To resolve this bottleneck problem, this study established a signal-processing strategy that improves the signal-to-noise ratio for the one-time measured signal of ultrasonic waves, by application of parallel factor analysis (PARAFAC) technology that produces unique multiway decomposition without additional orthogonal or independent constraints.An experimental study has revealed that the final result is consistent with the conventional 1024-data averaging signal, and relative error evaluation has indicated that the signal-to-noise ratio of ultrasonic waves can be significantly improved.

View Article: PubMed Central - PubMed

Affiliation: Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan. topzrc@iis.u-tokyo.ac.jp.

ABSTRACT
Ultrasonic wave-sensing technology has been applied for the health monitoring of composite structures, using normal fiber Bragg grating (FBG) sensors with a high-speed wavelength interrogation system of arrayed waveguide grating (AWG) filters; however, researchers are required to average thousands of repeated measurements to distinguish significant signals. To resolve this bottleneck problem, this study established a signal-processing strategy that improves the signal-to-noise ratio for the one-time measured signal of ultrasonic waves, by application of parallel factor analysis (PARAFAC) technology that produces unique multiway decomposition without additional orthogonal or independent constraints. Through bandpass processing of the AWG filter and complex wavelet transforms, ultrasonic wave signals are preprocessed as time, phase, and frequency profiles, and then decomposed into a series of conceptual three-way atoms by PARAFAC. While an ultrasonic wave results in a Bragg wavelength shift, antiphase fluctuations can be observed at two adjacent AWG ports. Thereby, concentrating on antiphase features among the three-way atoms, a fitting atom can be chosen and then restored to three-way profiles as a final result. An experimental study has revealed that the final result is consistent with the conventional 1024-data averaging signal, and relative error evaluation has indicated that the signal-to-noise ratio of ultrasonic waves can be significantly improved.

No MeSH data available.


Related in: MedlinePlus

Variation of the reflection spectrum between two ports of the AWG filter.
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sensors-15-16388-f002: Variation of the reflection spectrum between two ports of the AWG filter.

Mentions: In this study, two pairs of adjacent ports of the AWG filter are adopted to reflect the wavelength shift from the two FBG sensors. As shown in Figure 2, when the Bragg wavelength of the FBG shifts upon the arrival of an ultrasonic wave, the areas of superposition of the reflection spectrum fluctuate between two adjacent ports of the AWG filter. In this situation, the area of superposition will increase for the port on one side and decrease for the port on the opposite side. Simply put, a significant ultrasonic wave can produce antiphase outputs for two adjacent ports of the AWG filter.


PARAFAC Decomposition for Ultrasonic Wave Sensing of Fiber Bragg Grating Sensors: Procedure and Evaluation.

Zheng R, Nakano K, Ohashi R, Okabe Y, Shimazaki M, Nakamura H, Wu Q - Sensors (Basel) (2015)

Variation of the reflection spectrum between two ports of the AWG filter.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541884&req=5

sensors-15-16388-f002: Variation of the reflection spectrum between two ports of the AWG filter.
Mentions: In this study, two pairs of adjacent ports of the AWG filter are adopted to reflect the wavelength shift from the two FBG sensors. As shown in Figure 2, when the Bragg wavelength of the FBG shifts upon the arrival of an ultrasonic wave, the areas of superposition of the reflection spectrum fluctuate between two adjacent ports of the AWG filter. In this situation, the area of superposition will increase for the port on one side and decrease for the port on the opposite side. Simply put, a significant ultrasonic wave can produce antiphase outputs for two adjacent ports of the AWG filter.

Bottom Line: Ultrasonic wave-sensing technology has been applied for the health monitoring of composite structures, using normal fiber Bragg grating (FBG) sensors with a high-speed wavelength interrogation system of arrayed waveguide grating (AWG) filters; however, researchers are required to average thousands of repeated measurements to distinguish significant signals.To resolve this bottleneck problem, this study established a signal-processing strategy that improves the signal-to-noise ratio for the one-time measured signal of ultrasonic waves, by application of parallel factor analysis (PARAFAC) technology that produces unique multiway decomposition without additional orthogonal or independent constraints.An experimental study has revealed that the final result is consistent with the conventional 1024-data averaging signal, and relative error evaluation has indicated that the signal-to-noise ratio of ultrasonic waves can be significantly improved.

View Article: PubMed Central - PubMed

Affiliation: Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan. topzrc@iis.u-tokyo.ac.jp.

ABSTRACT
Ultrasonic wave-sensing technology has been applied for the health monitoring of composite structures, using normal fiber Bragg grating (FBG) sensors with a high-speed wavelength interrogation system of arrayed waveguide grating (AWG) filters; however, researchers are required to average thousands of repeated measurements to distinguish significant signals. To resolve this bottleneck problem, this study established a signal-processing strategy that improves the signal-to-noise ratio for the one-time measured signal of ultrasonic waves, by application of parallel factor analysis (PARAFAC) technology that produces unique multiway decomposition without additional orthogonal or independent constraints. Through bandpass processing of the AWG filter and complex wavelet transforms, ultrasonic wave signals are preprocessed as time, phase, and frequency profiles, and then decomposed into a series of conceptual three-way atoms by PARAFAC. While an ultrasonic wave results in a Bragg wavelength shift, antiphase fluctuations can be observed at two adjacent AWG ports. Thereby, concentrating on antiphase features among the three-way atoms, a fitting atom can be chosen and then restored to three-way profiles as a final result. An experimental study has revealed that the final result is consistent with the conventional 1024-data averaging signal, and relative error evaluation has indicated that the signal-to-noise ratio of ultrasonic waves can be significantly improved.

No MeSH data available.


Related in: MedlinePlus