The research objective of this award is to explore the signal group delay induced by chromatic dispersion in optical fibers and its application in long-span, high speed distributed fiber optic sensing. The approach will be to multiplex a large number of identical weak reflecting fiber Bragg gratings in a single optical fiber and to interrogate them with a fast spectrum-to-time conversion method. This dynamic spectrum characterization to a delay-time measurement circumvents the requirements of heavy averaging and dynamic spectral analysis as encountered in the current distributed fiber sensor products. The thermal stability of the ultra-weak gratings used in the system will be investigated for their improved performance at high temperatures.
If successful, the benefits of this research will include dynamic health monitoring of many civil and industrial structures and systems and low cost seismological oil and gas exploration. This technology may also be useful to earth quake detection and volcano activity monitoring. The multidisciplinary nature of the research will offer balanced training for the participating students, enrich the current photonics curriculum at Virginia Tech and promote the involvement of students from underrepresented minority groups in the scientific and engineering research.
