This paper investigates the influences of a semiconductor laser with narrow linewidth on a fibre-optic distributed disturbance sensor based on Mach-Zehnder interferometer. It establishes an effective numerical model t...This paper investigates the influences of a semiconductor laser with narrow linewidth on a fibre-optic distributed disturbance sensor based on Mach-Zehnder interferometer. It establishes an effective numerical model to describe the noises and linewidth of a semiconductor laser, taking into account their correlations. Simulation shows that frequency noise has great influences on location errors and their relationship is numerically investigated. Accordingly, there is need to determine the linewidth of the laser less than a threshold and obtain the least location errors. Furthermore, experiments are performed by a sensor prototype using three semiconductor lasers with different linewidths, respectively, with polarization maintaining optical fibres and couplers to eliminate the polarization induced noises and fading. The agreement of simulation with experimental results means that the proposed numerical model can make a comprehensive description of the noise behaviour of a semiconductor laser. The conclusion is useful for choosing a laser source for fibre-optic distributed disturbance sensor to achieve optimized location accuracy. What is more, the proposed numerical model can be widely used for analysing influences of semiconductor lasers on other sensing, communication and optical signal processing systems.展开更多
The presence of process-induced strains induced by various manufacturing and operational factors is one of the characteristics of polymer composite materials(PCM).Conventional methods of registration and evaluation of...The presence of process-induced strains induced by various manufacturing and operational factors is one of the characteristics of polymer composite materials(PCM).Conventional methods of registration and evaluation of process-induced strains can be laborious,time-consuming and demanding in terms of technical applications.The employment of embedded fibre-optic strain sensors(FOSS)offers a real prospect of measuring residual strains.This paper demonstrates the potential for using embedded FOSS for recording technological strains in a PCM plate.The PCM plate is manufactured from prepreg,using the direct compression-moulding method.In this method,the prepared reinforcing package is placed inside a mould,heated,and then exposed to compaction pressure.The examined technology can be used for positioning FOSS between the layers of the composite material.Fibre-optic sensors,interacting with the material of the examined object,make it possible to register the evolution of the strain process during all stages of polymer-composite formation.FOSS data were recorded with interrogator ASTRO X 327.The obtained data were processed using specially developed algorithms.展开更多
文摘This paper investigates the influences of a semiconductor laser with narrow linewidth on a fibre-optic distributed disturbance sensor based on Mach-Zehnder interferometer. It establishes an effective numerical model to describe the noises and linewidth of a semiconductor laser, taking into account their correlations. Simulation shows that frequency noise has great influences on location errors and their relationship is numerically investigated. Accordingly, there is need to determine the linewidth of the laser less than a threshold and obtain the least location errors. Furthermore, experiments are performed by a sensor prototype using three semiconductor lasers with different linewidths, respectively, with polarization maintaining optical fibres and couplers to eliminate the polarization induced noises and fading. The agreement of simulation with experimental results means that the proposed numerical model can make a comprehensive description of the noise behaviour of a semiconductor laser. The conclusion is useful for choosing a laser source for fibre-optic distributed disturbance sensor to achieve optimized location accuracy. What is more, the proposed numerical model can be widely used for analysing influences of semiconductor lasers on other sensing, communication and optical signal processing systems.
基金The results of sections 2 and 3 were obtained within the RSF grant[project No.14-29-00172-Π]The result s of sections 4 and 5 were obtained within the RFBR[project No.17-41-590684 r-ural-a].
文摘The presence of process-induced strains induced by various manufacturing and operational factors is one of the characteristics of polymer composite materials(PCM).Conventional methods of registration and evaluation of process-induced strains can be laborious,time-consuming and demanding in terms of technical applications.The employment of embedded fibre-optic strain sensors(FOSS)offers a real prospect of measuring residual strains.This paper demonstrates the potential for using embedded FOSS for recording technological strains in a PCM plate.The PCM plate is manufactured from prepreg,using the direct compression-moulding method.In this method,the prepared reinforcing package is placed inside a mould,heated,and then exposed to compaction pressure.The examined technology can be used for positioning FOSS between the layers of the composite material.Fibre-optic sensors,interacting with the material of the examined object,make it possible to register the evolution of the strain process during all stages of polymer-composite formation.FOSS data were recorded with interrogator ASTRO X 327.The obtained data were processed using specially developed algorithms.
