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光纤传感器的研究在国外是从1977年开始的.几年来,研究进展迅速,目前已有大约60种不同型式的光纤传感器,包括磁的、声的、压力的、温度的、加速的、陀螺的、位移的、液面高低的、扭转的、电流的和应力的许多不同的光纤传感器.经过几年的研究,传感灵敏度提高了许多倍,超过从前非光纤传感器的性能.这表明,光纤传感器大有发展前途,但也应承认还有许多实际问题尚待研究解决. 光纤传感器的明显优点有:1.比原有的非光纤传感器提高了灵敏度;2.几何上的易变性,可以按需要构成任意形状的传感器;3.技术方法的共同性,可以对各种不同的物理扰动,例如声、磁、旋转、温度等变化,做成相互类似的传感器;4.由于光纤是介质,它可以在高电压、大噪声、高温、有腐蚀性、或有其它应力的环境中起传感作用;5.它可以与光纤遥测技术配合一 相似文献
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商海英 《光纤光缆传输技术》2005,(4):36-47
概述了葡萄牙在过去的15年间在光纤传感方面开展的研究和开发活动。探讨了不同的专题。包括干涉型、强度和布喇格光栅光纤传感器,信号处理和多路复用技术,光学电流传感器.以及一些参考性的现场试验和应用。概述了针对本课题葡萄牙现在和将来进行研究和开发活动的适用准则。 相似文献
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本文综述了近几年来机敏复合材料与结构中损伤探测系统的研究概况,包括各类光纤损伤探测阵列及其信号处理技术的研究进展。 相似文献
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提出了一种低成本的新型强度调制型光纤温度传感器。该传感器主要由宽谱光源、三端口光环形器、光纤耦合器、偏振控制器、PMF光纤、光电探测器,以及信号处理单元组成。在较短的PMF光纤条件下,温度变化会对PMF光纤双折射产生直接影响,导致两相干光束产生一定的相移变化,使经过Sagnac环干涉后具有不同的透射光谱,即发生波长漂移。利用光电转换和信号处理,将检测到的光信号转换为电压信号,对其进行解算从而完成对温度的检测。在无需光谱分析仪的情况下,通过对Sagnac干涉仪的透射光谱进行信号处理,根据随温度的变化函数解算出测量温度。在25~50.5℃的温度范围内进行了实验,测试结果表明该光纤温度传感器的灵敏度为0.066mW/℃,分辨率为0.34℃。 相似文献
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详细论述了光纤传感器在海洋科学领域,包括海洋的温度、压力、盐度、pH值、溶解氧浓度和浮游植物的叶绿素a的浓度等方面的应用与研究进展,对传统测量方法和光纤传感技术测量方法进行了比较。可以预见,光纤传感器对保护和监测海洋环境、开发海洋资源以及发展海洋养殖业具有重要的现实意义。 相似文献
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光纤隐失波传感器具有设计简单、灵敏度高、易与其他传感技术相结合的特点,被广泛应用于生物和化学传感领域.概述了光纤隐失波传感的定义和常用的光纤种类;总结了光纤隐失波传感器的优化方法和原理;回顾了石英光纤以及硫系光纤在生化传感领域的研究进展,并展望了今后的发展方向和趋势. 相似文献
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为了测试光纤电流互感器中由于Faraday效应引起的旋转量,提出了采用锁相放大器处理信号的方法,改进了传统的将交流成分与直流成分相除的方法。系统将采集信号做单端电压输入测试和差分电压输入测试,并比较了单端输入与差分输入的测试效果,定性分析了输出幅值与被测电流的关系。测试结果表明,锁相放大器输出幅值与被测电流具有线l陛关系,且差分输入较单端输入幅值大、线性度好、对外界干扰抑制性强。其成果为进一步研究基于旋光效应的光纤电流互感器的应用奠定了基础。 相似文献
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对现有强度调制型光纤麦克风做了分析和讨论,采用单模光纤(SMF)熔接多模光纤(MMF)的方法设计了一种新的反射式光纤麦克风。适当长度的折射率分布为抛物线形的多模光纤具有准直透镜的作用,直接熔接在单模光纤上,可以使光纤麦克风进一步微型化、成本低廉化。用单频正弦波信号做声源测试该光纤麦克风,输出正弦波电压信号与声源频率一致,振幅随声源振幅线性变化。结果表明,该结构的光纤麦克风在原理和实验上可以用于语音通信中。 相似文献
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This paper examines code-division multiple-access (CDMA) techniques used in slotted fiber-optic packet networks. Since the inherent properties and signal processing of the conventional communication channels are different from those of the fiber-optic channels, new code sequences must be constructed for fiber-optic applications. The goal of our research is to analyze the performance of fiber-optic CDMA packet networks using code sequences with given orthogonality properties 相似文献
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The conditions under which processing reduces to a single threshold comparison is derived for the binary orthogonal likelihoodratio, detection of a signal embedded in additive, independent noise. The range of the signal and noise is assumed to be discrete. Optimal processing of the observation vector, as Well as two commonly used ad hoc processing schemes, are discussed. It is shown, in all three cases, that single-threshold processing is optimal, provided a weak condition on the noise is satisfied, independent of the signal. The results are presented in the context of a PCM/FSK photocounting fiber-optic communication system in which the noise is considered to be of the Poisson or avalanche types. Although single-threshold processing is shown to be optimal in most cases, examples are presented where single-threshold processing is not optimal. 相似文献
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All-optical systems, which perform signal processing functions optically so that the signal conversion from optical to electrical is done only when desired, are considered. Three such schemes are discussed, namely, fiber-optic code-division multiple-access (CDMA) systems, neuromorphic CDMA systems, and ultrashort-light-pulse CDMA systems. Fiber-optic CDMA systems in which incoherent optical signal processing techniques are used to establish optical CDMA systems are first examined. In particular, a novel class of sequences for incoherent fiber-optic CDMA systems, called optical orthogonal codes, are discussed. The codes are then applied to neuromorphic optical systems, and various applications of the networks are examined. Recent experiments that demonstrate the ability to encode and decode extremely fast, femtosecond optical pulses and that suggest the possibility of ultrahigh-speed CDMA systems based on ultrashort light pulses are described 相似文献
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Voltage-controlled optical/RF phase shifter 总被引:1,自引:0,他引:1
A new fiber-optic device designed to steer the radiation beam of a phased-array antenna has been demonstrated. A radiofrequency (RF) signal at 125 MHz is generated via photomixing at the output of a single-mode fiber-optic interferometer. The phase of the electrical signal is shifted over several cycles in direct proportion to a voltage applied to an optical controller. The controller consists of a Pockels-type optical phase modulator located in one arm of the heterodyne interferometer. Rapid changes in RF phase are feasible. A miniature low-voltage version of the device, based upon integrated optics, is proposed. 相似文献
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光纤数据接收单元的设计和实现 总被引:1,自引:1,他引:0
完成了用于某数字阵雷达试验阵系统光纤数据接收单元的设计和开发工作。该单元作为雷达T/R组件和信号处理分系统之间的桥梁,通过光纤完成雷达回波数据的接收,同时可以实现雷达回波数据一个重复周期的乒乓存储和传输。除此之外,光纤数据接收单元实现了与雷达定时监控分系统的串口通信功能。给出了一种基于FPGA和光纤接收模块的实现方案,介绍了光纤数据接收单元的系统构成、硬件接口电路设计以及FPGA中各个控制模块的开发。 相似文献
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This paper examines code-division multiple-access (CDMA) techniques used in unslotted fiber-optic packet networks. Since the inherent properties and signal processing of the conventional communication channels are different from those of the fiber-optic channels, new code sequences must be constructed for fiber-optic applications. In unslotted systems, the exact solution is very difficult to obtain. Therefore, two approximation methods are presented to analyze the performance of such systems. Simulation is performed to verify the accuracy of the results 相似文献
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刘英明 《光纤与电缆及其应用技术》2009,(6):18-21
介绍一种用于光纤水听器阵列的时分复用(TDM)及解复用信号处理系统,该系统基于PC机,设计开发方便、使用灵活。采用Labview编写的信号处理软件可实现8单元水听器阵列的时分复用及解复用。 相似文献