Font Size: a A A

Design And Study On Distributed Optical Fiber Strain Sensing System

Posted on:2007-07-22Degree:MasterType:Thesis
Country:ChinaCandidate:T YuFull Text:PDF
GTID:2178360182483121Subject:Measuring and Testing Technology and Instruments
Abstract/Summary:PDF Full Text Request
Distributed optical fiber strain sensor is a new sensing technique arisingrecently. It has important application foreground in heavy structure and devicesuch as multilayer architecture, bridge, dam, aerocraft, pressure vessel and soon, since it can apperceive spatial distribution of strain and pressure ontransmission path and information changed with time. Based on study ofnonlinear optics, Brillouin spectroscopy and distributed optical fiber strainsensor of predecessors, surrounding improvement of system performance, weestablished a relatively complete mathematic model building of distributedoptical fiber strain sensing system and performed calculation of each parameterto establish theoretical basis for reasonable system design.The primary studies are as follows:(1) Firstly we introduced study status and several basic methods ofdistributed optical fiber sensor both home and abroad. By comparison andanalysis of many feasible schemes for Brillouin distributed optical fiber strainsensing technique, and based on fabrication process, system precision andexisting components of home and abroad, we finally chose distributed opticalfiber strain sensing scheme which was based on stimulated Brillouin scattering.(2) Through introducing scattering light in optical fiber, we presentedquantitative description of stimulated Brillouin scattering light, and importedconcept of Brillouin power threshold. By quantificationally analyzing, wedemonstrated good linear relationship between Brillouin scattering light andstrain, temperature of optical fiber, and also presented process of parametercalculation, which provided theory for correctly using distributed optical fiberstrain sensing system.(3) We showed structure diagram for distributed optical fiber strainsensing system, discussed each part of the sensing system, selected workingwavelength of laser, and accomplished driving circuit's design for two lasers.(4) Introducing solution of several key issues of system design, and puttingforward a new temperature compensation scheme for this system. Parts ofsensing system experiment are completed and firm basis for implementation ofwhole system are settled.
Keywords/Search Tags:Strain sensor, Distributed optical fiber, OTDR technique, Brillouin scattering, Mach-Zehnder interferometer
PDF Full Text Request
Related items