We want to present the e-newsletter for sharing updates in the … · Chirped fiber bragg gratings...
2
Vol. 2 Number 7 September 2013 Article News Letter newsletter@fiberoptika.com We want to present the e-newsletter for sharing updates in the field of fiber optics and optical communication. We solicit your feedback as well as contributions towards it. Chirped fiber bragg gratings for dispersion compensation Shweta Pant Optical fiber playing the most active role in communication nowadays is definitely the fastest, reliable and secure mode of communicating information. In addition it has an enormous capacity of carrying information which we call technically as bandwidth. Optical fiber can carry information, modulated or non-modulated, to thousands of kilometres without much loss. This feature of optical fiber is what makes it most attractive for long haul communications. The grey side of the optical fiber is loss due to dispersion which is most prominent among all the losses occurring in the fiber communication. Dispersion is an effect which leads to the loss of information as light travels through some distance. Dispersion is a phenomenon which causes the delay in the light pulse and hence pulse broadening giving rise to the inter symbol interference (ISI) and eventually loss of the signal. Hence dispersion is the most undesirable characteristic of an optical fiber. Amongst many type of dispersion which effects optical fiber communication, chromatic dispersion is the dominant one. Chromatic dispersion occurs due to the presence of a band of wavelengths (although narrow) in a light beam passing through the fiber and the wavelength dependency of refractive index. Hence different wavelengths experience different refractive indices which lead to their varying speeds and hence the varying delay. This delay effect is commonly known as Chromatic dispersion. Many techniques have been explored for reducing the dispersion effects. These include dispersion compensating fibers (DCF), dispersion shifted fibers (DSF), dispersion flattened fibers, solitons and many others. Chirped fiber Bragg grating is a promising solution for dispersion compensation. Chirp literally means the varying sounds which birds used to produce and technically refers to the process of introducing some kind of variation. In fibers, when gratings are made with varying grating period it is said to be chirped fiber Bragg gratings. Chirped Fiber gratings could be in either increasing or decreasing grating period or can even be with non-uniform grating periods according to the desired feature. Due to its varying grating period over the fiber, the light travelling through it encounters different Bragg wavelengths leading to reflection of different wavelengths with different delays. If this delay is somehow made to compensate the delay due to chromatic dispersion in optical fibers, the output will be a complete dispersion free communication system [1]. Chirped fiber gratings are used in WDM links so as to provide an efficient communication system without dispersion [2]. References: [1] “Fiber Bragg Gratings: The dispersion compensation technology for 40G and 100G optical transport”, Fredrick Sjostrom, Electronic design. [2] “Fiber Bragg Gratings for dispersion compensation in optical communication systems”, M. Sumetsky, B. J. Eggleton, Journal of optical and fiber communications report, September 2005, Volume 2, Issue 3.
Transcript of We want to present the e-newsletter for sharing updates in the … · Chirped fiber bragg gratings...
Vol. 2 Number 7September 2013
Artic
le
News Letter
We want to present the e-newsletter for sharing updates in the field of
fiber optics and optical communication. We solicit your feedback as well as contributions towards it.
Chirped fiber bragg gratings for dispersion compensation Shweta Pant
Optical fiber playing the most active role in communication nowadays is definitely the fastest,
reliable and secure mode of communicating information. In addition it has an enormous capacity of
carrying information which we call technically as bandwidth. Optical fiber can carry information,
modulated or non-modulated, to thousands of kilometres without much loss. This feature of optical fiber is
what makes it most attractive for long haul communications.
The grey side of the optical fiber is loss due to dispersion which is most prominent among all the
losses occurring in the fiber communication. Dispersion is an effect which leads to the loss of information
as light travels through some distance. Dispersion is a phenomenon which causes the delay in the light
pulse and hence pulse broadening giving rise to the inter symbol interference (ISI) and eventually loss of
the signal. Hence dispersion is the most undesirable characteristic of an optical fiber. Amongst many type of
dispersion which effects optical fiber communication, chromatic dispersion is the dominant one.
Chromatic dispersion occurs due to the presence of a band of wavelengths (although narrow) in a light
beam passing through the fiber and the wavelength dependency of refractive index. Hence different
wavelengths experience different refractive indices which lead to their varying speeds and hence the
varying delay. This delay effect is commonly known as Chromatic dispersion. Many techniques have been
explored for reducing the dispersion effects. These include dispersion compensating fibers (DCF),
dispersion shifted fibers (DSF), dispersion flattened fibers, solitons and many others.
Chirped fiber Bragg grating is a promising solution for dispersion compensation. Chirp literally
means the varying sounds which birds used to produce and technically refers to the process of introducing
some kind of variation. In fibers, when gratings are made with varying grating period it is said to be chirped
fiber Bragg gratings. Chirped Fiber gratings could be in either increasing or decreasing grating period or
can even be with non-uniform grating periods according to the desired feature. Due to its varying grating
period over the fiber, the light travelling through it encounters different Bragg wavelengths leading to
reflection of different wavelengths with different delays. If this delay is somehow made to compensate the
delay due to chromatic dispersion in optical fibers, the output will be a complete dispersion free
communication system [1]. Chirped fiber gratings are used in WDM links so as to provide an efficient
communication system without dispersion [2].
References:[1] “Fiber Bragg Gratings: The dispersion compensation technology for 40G and 100G optical transport”, Fredrick Sjostrom, Electronic design.
[2] “Fiber Bragg Gratings for dispersion compensation in optical communication systems”, M. Sumetsky, B. J. Eggleton, Journal of optical and fiber communications report, September
2005, Volume 2, Issue 3.
Fiber Optika Technologies Pvt Ltd.Follow us on:
LIGHT RUNNER FEATURES
Front Panel Block
CIRCULATOR Block
This is a three-port optical circulator which acts as anonreciprocal device. If light is launched at Port 1, it will be passed to Port 2.Conversely if light is launched at Port 2 then instead of appearing at Port1, it will appear at Port 3 unlike in most of the optical devices.
Custo
mer’
s S
peak
What’
s N
ew
Head Office
6/7, Industrial Town W.O.C RoadRajajinagar, Bengaluru, Karnataka 560044E mail: [email protected] site: www.fiberoptika.comPh:-080 23113241/42, 080-41673517
Representative Office (North India)
101A, RG Square, I. P Extension, Patparganj Delhi - 110 092Landline: +91-11- 45037430E mail: [email protected]
Mumbai Office
B-36, Gurudev ApartmentB Wing, 3rd FloorOpp. Telephone ExchangeChembur NakaMumbai - 400 071
FIBER OPTIKA had attended 2 days Indian Technology Congress 2013 at NIMHANS Convention Center, Bangalore.Our Product LIGHT RUNNER & LIGHTSIM were displayed at the event.
Many Ent repreneurs , Researchers , Technologists, Academicians & Students had visited our stall. The products were liked and appreciated by the visitors.
A series of demonstrations of LIGHT RUNNER & LIGHTSIM were carried out at different Engineering Colleges and Institutes at Jaipur and Delhi . Both the products were well appreciated by the visitors.
Indian Technology Congress 2013On Advanced Communication Technologies
Faculty Development Programme
D P F
D P F
Indian Technology Congress 2013
Light Runner Demonstrations at Delhi & Jaipur
![Hot water-assisted fabrication of chirped polymer optical fiber ......Since the first polymer optical fiber Bragg grating (POFBG) was reported in 1999 [6], different polymer materials](https://static.fdocuments.in/doc/165x107/60bb1cc2cfed7110310e8169/hot-water-assisted-fabrication-of-chirped-polymer-optical-fiber-since-the.jpg)
