Signal processing techniques for optical fiber sensors using white light interferometry

Conventional fiber optic interferometric sensors employing a monochromatic source prove to be inadequate for applications requiring absolute, real-time value of magnitude and direction of the applied perturbation. This limitation can be overcome by using a broadband light source to extract unambiguous information from the sensor in the wavelength domain. Several variations in the signal processing techniques for white light interferometry are discussed and compared in terms of resolution, bandwidth and cost. A detailed analysis is made of the principle of operation and basic features of the commercially available absolute sensing system. This compact system is self calibrating, has a 100 micro-strain Ole) strain and 2°C temperature resolution and is ideal for applications in environments where the parameter to be measured is static or quasi-static. High finesse Fabry-Perot cavities are employed to obtain almost an order of magnitude sensitivity improvement over conventional low finesse cavities. The principle of white light interferometry is extended to absolute axial stain and temperature sensing in two-mode, elliptical-core fibers. Other novel applications, such as to operation of photo induced refractive index gratings and fiber characterization are proposed.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical Engineering

Department dc:contributor.department

Electrical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1993

Author dc:creator

• Bhatia, Vikram

Chair dc:contributor.committeechair

• Murphy, Kent A.

Committee members dc:contributor.committeemember

• Claus, Richard O.
• Jacobs, Ira
• Wang, Anbo

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-09192009-040440

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/44866