Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fiber optics: One and only

19.08.2011
The transmission quality of an optical fiber can now be tested without the need to take measurements at both ends

Light traveling in an optical fiber loses power over distance. A number of factors are responsible for this power loss, but one that is particularly important at high data rates is the loss that occurs due to changes in light polarization.

Hui Dong at the A*STAR Institute for Infocomm Research and co-workers1 have developed and tested a method of determining this polarization-dependent loss (PDL) in an optical fiber cable by taking measurements from just one end of the fiber. The new technique avoids the difficulty of having to arrange and coordinate access to both ends of a fiber optic cable, which may be tens of kilometers apart.

In fiber optic networks, PDL predominantly occurs not in the fiber itself but in the couplers and filters used to regulate light in the fiber, and can have a significant impact on signal quality and network performance. Until now the measurement of PDL in cables has required an optical source attached to one end transmitting to a receiver at the other. A technique requiring access to only one end, however, was proposed theoretically by Italian researchers, but had yet to be verified experimentally.

The proposed technique requires the fiber optic cable to be birefringent at the end at which measurements are to be taken— that is, the cable must include imperfections that interact in different ways with the two perpendicular components of light polarization. This polarization-dependent interaction causes the two polarization modes to travel at different speeds, splitting the light beam into two.

The technique then proposes estimating the PDL from the maximum loss encountered in a round-trip along the cable. This can be achieved by measuring light backscatter as photons of light emitted in four different polarization states bounce back from interacting with the molecular structure of the cable. Over a distance of ten kilometers, measurements taken with an experimental setup built by the researchers showed good agreement with measurement made using standard techniques with a light source and receiver at either end.

“We want to continue the experimental work on our PDL measurement in fiber links,” says Dong. “The PDL in a fiber link is a function of fiber length. Using our new technique, we should be able to measure the relationship between PDL and fiber length.” As PDL varies with environmental conditions such as temperature or stress on the cable, the new technique could also be used to sense these changes by detecting PDL variations.

References

Dong, H., Shum, P., Gong, Y. & Sun, Q. Single-ended measurement of polarization-dependent loss in an optical fiber link. IEEE Photonics Technology Letters 23, 185–187 (2011).

Eugene Low | Research asia research news
Further information:
http://www.i2r.a-star.edu.sg/
http://www.researchsea.com

Further reports about: Fiber Optic Cables PDL fiber optic cable optical fiber optical source

More articles from Materials Sciences:

nachricht Researchers shoot for success with simulations of laser pulse-material interactions
29.03.2017 | DOE/Oak Ridge National Laboratory

nachricht Nanomaterial makes laser light more applicable
28.03.2017 | Christian-Albrechts-Universität zu Kiel

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>