共查询到20条相似文献,搜索用时 15 毫秒
1.
《IEEE transactions on instrumentation and measurement》1980,29(1):71-73
This paper describes a design and the characteristics of a new optical power meter for 0.8-?m wavelength region optical fiber transmission systems. Features of this optical power meter are high sensitivity (-80 dBm), high stability (±0.005 dB at > -65 dBm), and small deviation against the plug rotation inside the receptacle (±0.02 dB). The SNR design method presented is useful in high sensitivity and high stability optical power meter design. 相似文献
2.
da Costa Antunes P.F. Lima H.F.T. Alberto N.J. Rodrigues H. Pinto P.M.F. de Lemos Pinto J. Nogueira R.N. Varum H. Costa A.G. de Brito Andre P.S. 《IEEE sensors journal》2009,9(11):1347-1354
In this study, the implementation of an optical accelerometer unit based on fiber Bragg gratings, suitable to monitor structures with frequencies up to 45 Hz, is reported. The developed optical system was used to estimate the structure eigenfrequencies of a steel footbridge, with a total length of 300 m, over the Sao Pedro Creek, located at University of Aveiro Campus, in Portugal. The acceleration records measured with this solution are compared with those obtained by traditional commercial electronic devices, revealing a root-mean-square error of 2.53 times 10-5 G. 相似文献
3.
给出了调顶技术对光纤通信系统误码特性影响的简单理论估计和实测结果:调顶深度小于5%时,调顶对系统接收机灵敏度的影响小于0.5dB。将专门研制的实用化调顶盘和解调顶盘用于实际的8信道WDM光纤通信系统中,能准确判断各信道的有无及其光功率的相对变化,并据此实现了EDFA的增益箝制。 相似文献
4.
Perez-Herrera R.A. Frazao O. Santos J.L. Araujo F.M. Ferreira L.A. Baptista J.M. Lopez-Amo M. 《IEEE sensors journal》2009,9(12):1647-1653
We report on the use of erbium doped fiber (EDF) amplification to enhance a frequency modulated continuous wave (FMCW) technique for referencing optical intensity sensors located between two Bragg grating structures. The experiment combines the concept of FMCW with the spectrally selective mirror properties of Bragg gratings to interrogate with referencing properties intensity based sensors. The interrogation system without amplification yields a sensor resolution of around 0.078 dB. When the EDF amplifier is introduced into the experimental set up, the sensor sensitivity does not change, but the signal-to-noise ratio is improved, resulting into an enhanced resolution of 0.025 dB. We also obtain a remote sensing operation at a location of 50 km, showing the feasibility of this configuration to be used as a remote sensing application. 相似文献
5.
CMOS摄像模组缺陷的自动检测系统研究 总被引:1,自引:0,他引:1
CMOS摄像模组缺陷检测要求系统能够检测光学镜头聚焦状况以及在摄像模组生产过程中产生的各种缺陷,包括:亮点、暗点、线缺陷、色差和暗斑等。为实现检测目的,系统使用CPLD通过帧捕捉把图像传输至计算机进行处理,运用多种图像处理算法来分析获取的不同图像,以检测出模组的相应缺陷。实验结果证明该系统在生产线上能够可靠运行,实现高速度高精度的缺陷检测。 相似文献
6.
研究了一个监控信道方案,用于WDM+EDFA光纤通信系统在线光纤放大器远程监控,并成功地实现了其演示系统,对该方案的实行性进行了论证。 相似文献
7.
绝对测量小距离的波长扫描-光纤双干涉仪系统 总被引:2,自引:0,他引:2
介绍了用于测量小位移的波长扫描-光纤法布里-珀罗干涉仪系统。用扫描波长作为“中介”,比较参考腔长和传感腔长,可以“准绝对”地测量传感腔的长度。这个测量与波长扫描的准确度无关,仅依赖于参考腔的长度,而通过将传感腔改变一个已知距离,就可以简单地“自标定”参考腔的长度。 相似文献
8.
提出并设计了一种基于Advanced RISC Machines(ARM)和General Packet Radio Service(GPRS)的远程数据传输系统,该系统用于光纤智能结构的健康监控。系统包括光源、光纤智能结构、光电检测电路、远程终端单元(RTU)、GPRS网络、Internet和监控中心服务器,其中终端单元由ARM微控制器和GPRS无线通信模块组成。RTU与监控中心之间是通过GPRS网络和Internet来进行数据交换的,在监控中心收到的数据中包含了复合材料智能结构的健康状态信息,通过对数据的处理就能判断材料结构的健康状态,从而达到对智能材料结构的健康状态进行远程监控的目的,同时还进行了相应的承载试验以及损伤定位研究。试验结果表明:该监控系统实现了对光纤智能结构的无线远程监控和损伤定位,且性能稳定可靠,为复合材料结构的健康状态监控提供了一种新方法。 相似文献
9.
Donno M. Palange E. Di Nicola F. Bucci G. Ciancetta F. 《IEEE transactions on instrumentation and measurement》2008,57(8):1614-1620
10.
11.
为解决石油生产多分相检测问题,研制了一种用于多分相检测的新型双接收端光纤传感器(NDR-FOP),利用ZEMAX光线追迹方法构建了双接收端环形耦合光路(DR-RCOP)模型。对通过NDR-FOP锥形敏感头的光线传输轨迹进行了数学描述与仿真分析。基于研究结果,对油气水多相流混相介质中NDR-FOP多分相检测性能进行了评价以及在实验平台上进行了测试研究,仿真与实验结果均表明:油气水介质之间的差特征值形成了明显的间距,NDR-FOP多分相检测是可行和有效的。 相似文献
12.
Polymer Optical Fiber Sensors for Distributed Strain Measurement and Application in Structural Health Monitoring 总被引:1,自引:0,他引:1
Liehr S. Lenke P. Wendt M. Krebber K. Seeger M. Thiele E. Metschies H. Gebreselassie B. Munich J.C. 《IEEE sensors journal》2009,9(11):1330-1338
Polymer optical fiber (POF) sensors have the unique ability to measure high strain distributed along the fiber up to 40% using the optical time-domain reflectometry (OTDR) technique. Both, standard PMMA fibers and perfluorinated (PF) graded-index (GI) POF are introduced and evaluated in potential use and applicability. Further, distributed length change measurement based on cross-correlation analysis of the characteristic fiber signature of PF POF is introduced. We conclude the advances in distributed POF strain sensors technology with respect to application in structural health monitoring. Special focus is on the sensor integration into technical textiles for health monitoring of geotechnical structures and masonry structures. Measurement results of sensor-equipped textiles in different model tests are presented, displacement of soil and cracks in retrofitted masonry structures are detected and evaluated. 相似文献
13.
14.
15.
MEMS光开关应用于机群系统光互连网络 总被引:3,自引:1,他引:3
建立了千兆位传输结构的高性能光互连网络 ,以提高计算机机群系统的网络性能 .利用MEMS 4× 4光开关和具有硬件路由功能的光互连网络PCI总线接口卡构成光互连链路 .光信号传输速率达 1Gbits/s以上 .基于MEMS的全光无堵塞光开关减少了光 电转换 ,开关方式与光信号的波长、速率和数据格式无关 .利用这种网络结构 ,可以最大限度地减少网络延迟和网络通信开销 ,提升了机群系统的总体性能 .利用MEMS 8× 8光开关设计了星型环型混合拓扑的光互连网络 .采用了具有硬件路由功能的光互连网络接口卡 ,并以Ethernet为控制网络实现了对MEMS光开光的动态配置 .分析并测试了光互连网络的通信性能 :峰值数据传输率可达 1Gbits/s ;数据量在 3Mbytes以上时 ,网络整体性能明显提高 相似文献
16.
光纤耦合成象系统的光学传递函数计算和分析 总被引:1,自引:1,他引:1
主要分析了光纤与CCD耦合技术各单元的参数的关系,通过变换实验系统中耦合物镜的参数,得到了不同的实验结果,从理论上给出了整个系统传递函数的数学模型,并对实验系统作模拟计算,与实验结果进行比较,分析出对实验系统光学传递函数的影响因素。 相似文献
17.
18.
19.