1,720,963 research outputs found
Dataset to support the article "High Sensing Accuracy Realisation with Millimetre/sub-Millimetre Resolution in Optical Frequency Domain Reflectometer"
No full textThis dataset is used for realizing high sensing accuracy and sub-millimetre resolution of Optical Frequency Domain Reflectometer. It is associated with the research paper "High Sensing Accuracy Realisation with Millimetre sub-Millimetre Resolution in Optical Frequency Domain Reflectometer" in Journal: Journal of Lightwave Technology.
This work was funded by High Value Manufacturing Catapult, grant reference, 160080 CORE (WMG), titled ‘Smart Sensing for Future Batteries’ and the EPSRC (Engineering and Physical Sciences Research Council), grant reference EP/R004927/1, titled ‘Prosperity Partnership’. The author Gaoce Han would like to acknowledge the China Scholarship Council for sponsoring.</span
Dataset to support the article "High-resolution 𝜙-OFDR using phase unwrap and nonlinearity suppression"
No full textThis dataset is used for realizing high resolution of phase-sensitive Optical Frequency Domain Reflectometer. It is associated with the research paper:
Guo Z, Yan J, Han G, Yu Y, Greenwood D and Marco J (2023) "High-Resolution φ-OFDR Using Phase Unwrap and Nonlinearity Suppression". Journal of Lightwave Technology, 41 (9), 2885-2891. (https://doi.org/10.1109/JLT.2023.3236775).
The data is presented as an excel file:
High_resolution_OFDR_using_phase_unwrap_and_nonlinearity_suppression.xlsx
This work was funded by High Value Manufacturing Catapult and the Engineer and Physical Sciences Research Council - EPSRC EP/V000624/1. The author Gaoce Han would like to acknowledge the China Scholarship Council for sponsoring.</span
Dataset supporting the University of Southampton Doctoral Thesis "High-performance Fibre-based and Silicon Photonics-based Optical Frequency Domain Reflectometry for Battery Sensing"
No full textThis dataset contains: both simulation and experimental results pertinent to the thesis. The dataset is accessible through Microsoft Excel or other similar software for comprehensive review. The data is presented as:
Dataset_for_High-performance_Fibre-based_and_Silicon_Photonics-based_Optical_Frequency_Domain_Reflectometry_for_Battery_Sensing.xlsx</span
High-performance fibre-based and silicon photonics-based optical frequency domain reflectometry for battery sensing
No full textOptical fibre sensors have attracted increasing attention in battery sensing. This thesis is dedicated to the development of two outstanding distributed optical fibre sensors based on optical frequency domain reflectometry (OFDR) for batteries. The research commences with a comprehensive analysis of the OFDR system, achieved through the establishment of a function-module-based theoretical model. This model enables modular analysis, single-device verification, and systematic comparison, providing a solid theoretical foundation for the research. Especially, an innovative equal frequency resampling method is proposed in this thesis to effectively compensate for the nonlinear frequency tuning noise, significantly enhancing the performance of the OFDR system. A fibre-based OFDR, optimizing the operating parameters and implementing the equal frequency resampling method, achieves remarkable experimental results. In this thesis, an unprecedented spatial resolution of 12.1 µm is obtained, setting a world record. This spatial resolution represents the ultimate spatial resolution attainable by a fibre-based OFDR up to this point in time. Moreover, this fibre-based OFDR is employed to conduct distributed temperature and strain sensing with exceptional performance. In this thesis, the distributed temperature measurements showcase a temperature uncertainty of 0.13 °C over an 8 m measurement range and 0.15 °C over a 102 m measurement range. Similarly, distributed strain measurements exhibit a strain accuracy of 0.51 µε at a 4 m fibre end and 1.86 µε at a 104 m fibre end, with an effective sensing spatial resolution of 5 mm. Additionally, a strain accuracy of 19.31 µε is achieved with an effective sensing spatial resolution of 0.5 mm. Furthermore, a real on-chip OFDR based on Rayleigh backscattering is proposed and demonstrated for the first time. In this thesis, an integrated OFDR utilizing silicon photonics technology is fabricated on a Silicon-on-Insulator (SOI) platform, replacing the fibre-based main interferometer module and auxiliary interferometer module with the on-chip photonic circuits. A distributed refractive index measurement confirms the potential and effectiveness of the silicon photonics-based OFDR, achieving an impressive experimental spatial resolution of 8.28 µm which is reaching its theoretical level. Both the fibre-based OFDR and the silicon photonics-based OFDR demonstrate exceptional sensing performance, fulfilling the requirements for battery sensing. The outcomes of this thesis contribute to the advancement of battery sensing and pave the way for the development of smart batteries
High sensing accuracy realisation with millimetre/sub-millimetre resolution in optical frequency domain reflectometer
Full text linkBy effectively suppressing the nonlinear sweep noise and random range of wavelength sweep in the optical frequency domain reflectometer, the theoretical spatial resolution and uniform sweep distribution are delivered for high sensing accuracy. A strain accuracy of 0.51 is realised with a 5 mm sensing resolution, while the accuracy is 5.89 with a 1 mm sensing resolution. Theoretical limitation between the strain accuracy and sensing resolution is further studied for the sub-millimetre resolution sensing. It is found that signal to noise ratio and frequency bandwidth of the calculated cross-correlation are critical factors in measuring accuracy. Increasing the sweep range can provide a better spatial frequency step for a high signal to noise ratio in the cross-correlation. With a 130 nm sweep range, the measurement accuracy is limited to 19.31 with a 0.5 mm sensing resolution. Besides, for the long-distance sensing of 104m, the measurement accuracy is 8.72 with a 1 mm sensing resolution
A review on various optical fibre sensing methods for batteries
Full text linkBatteries have rapidly evolved and are widely applied in both stationary and transport applications. The safe and reliable operation is of vital importance to all types of batteries, herein an effective battery sensing system with high performance and easy implementation is critically needed. This also requires the sensing system to monitor the states of batteries in real time. Among the available methods, optical fibre sensors have shown a significant advantage due to their advanced capabilities of which include the fast measurement of multiple parameters with high sensitivity, working without interfering the battery performance, being able to be composited in multiplexed configurations and being robust to various harsh environment conditions. This paper mainly discusses the current optical fibre sensing methods for batteries in terms of the working principles and critical reviews the sensing performance corresponding to different sensing parameters. Moreover, the challenges and outlooks for future research on battery sensing are derived
High-resolution ϕ-OFDR using phase unwrap and nonlinearity suppression
Full text linkPhase-sensitive optical frequency domain reflectometer (Φ-OFDR) is investigated to deliver an accurate distributed measurement with high spatial resolution. It is found that random phase noise and quadrant discrimination during phase calculation are the main reasons for the random hopping in Φ-OFDR. By efficiently eliminating random hopping in the phase unwrap and suppressing the laser-induced nonlinear sweep for the theoretical spatial resolution, the proposed Φ-OFDR is proved to be able to decouple the limitation between resolution and accuracy in coherent OFDR (C-OFDR). Distributed strain measurement with 20 mm spatial resolution in Φ-OFDR is obtained and analysed. Measurement with little deviation and uniform sensitivity between applied strain and phase change both validate the efficient noise suppression for extreme resolution measurement. Then the influence of the initial sweep frequency between two times measurements is studied. With a further reduced 800 µm spatial resolution, the proposed Φ-OFDR is able to retain accurate distributed measurement compared to conventional C-OFDR methods. Besides, the computation time of the Φ-OFDR is only 3.2% of the C-OFDR
Ultimate spatial resolution realisation in optical frequency domain reflectometry with equal frequency resampling
Full text linkA method based on equal frequency resampling is proposed to suppress laser nonlinear frequency sweeping for the ultimate spatial resolution in optical frequency domain reflectometry. Estimation inaccuracy of the sweeping frequency distribution caused by the finite sampling rate in the auxiliary interferometer can be efficiently compensated by the equal frequency resampling method. With the sweeping range of 130 nm, a 12.1 µm spatial resolution is experimentally obtained. In addition, the sampling limitation of the auxiliary interferometer-based correction is discussed. With a 200 m optical path delay in the auxiliary interferometer, a 21.3 µm spatial resolution is realised at the 191 m fibre end. By employing the proposed resampling and a drawing tower FBG array to enhance the Rayleigh backscattering, a distributed temperature sensing over a 105 m fibre with a sensing resolution of 1 cm is achieved. The measured temperature uncertainty is limited to ±0.15 °C
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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