A Study on Uniform and Apodized Fiber Bragg GratingsIJSRD
The design, simulation and analysis of an optical Fiber Bragg Grating for maximum reflectivity, minimum side lobe power wastage has been done using MATLAB software. The reflection spectra and side lobes strength were analyzed with different grating lengths, refractive index profiles and pitch values. The simulations are based on coupled mode equations and transfer matrix method that describes the interaction of guided modes.
Optimization of Uniform Fiber Bragg Grating Reflection Spectra for Maximum Re...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
STUDY ON FIBER GRATINGS AND ITS CHARACTERIZATIONDr. Ved Nath Jha
Good potential uses in fiber and fiber lasers have been seen through Random Fiber Gratings (RFGs). However, a quantitative link has never been studied between the RFG's randomness and spectral reaction. This paper first experimentally characterizes two RFGs of varying degrees of randomness by optical frequency reflectometry (OFDR). The high degree of randomness indicates that the grating intensity is limited and the strength variations in spatial domain are large. The experimental findings show. Study establishes the theoretical basis for the optimization configuration and implementation of the long-term fiber grating in the area of fiber optics sensing and communication.
A Study on Uniform and Apodized Fiber Bragg GratingsIJSRD
The design, simulation and analysis of an optical Fiber Bragg Grating for maximum reflectivity, minimum side lobe power wastage has been done using MATLAB software. The reflection spectra and side lobes strength were analyzed with different grating lengths, refractive index profiles and pitch values. The simulations are based on coupled mode equations and transfer matrix method that describes the interaction of guided modes.
Optimization of Uniform Fiber Bragg Grating Reflection Spectra for Maximum Re...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
STUDY ON FIBER GRATINGS AND ITS CHARACTERIZATIONDr. Ved Nath Jha
Good potential uses in fiber and fiber lasers have been seen through Random Fiber Gratings (RFGs). However, a quantitative link has never been studied between the RFG's randomness and spectral reaction. This paper first experimentally characterizes two RFGs of varying degrees of randomness by optical frequency reflectometry (OFDR). The high degree of randomness indicates that the grating intensity is limited and the strength variations in spatial domain are large. The experimental findings show. Study establishes the theoretical basis for the optimization configuration and implementation of the long-term fiber grating in the area of fiber optics sensing and communication.
Performance Investigation and Enhancement of Fiber Bragg Gratingfor Efficient...IOSRJECE
In this paper, the performance of various windowfunctions for Fiber Bragg Grating Sensor (FBGS)is investigated and evaluated in order to get optimized reflection spectrum with high reflectivity and an efficient side lobe suppression for efficient sensing measurement applications.For this purpose, a wide range of design parameters which include grating length and refractive index modulation amplitudehas been chosen to evaluate the sensor design. The performances of the different windowfunctions have been then compared in terms of reflectivity, full width half maximum bandwidth (FWHM), and sidelobe level(SLL) so as to get the most suitable design parametersto be used for sensing measurement.The simulation results presented in this paper show the effectiveness of the optimizedFBG sensor, which can be further implemented for high performance sensing applications.
Profile of Single Mode Fiber Coupler Combining with Bragg GratingTELKOMNIKA JOURNAL
This paper describes a numerical experiment of design and operation of a fiber coupler between
single mode fiber and fiber Bragg grating (FBG). Both components are coupled depending with optical
waveguide and source parameters. A characterization of fiber coupler is simulated by varying long grating
of 10 mm to 60 mm using transfer matrix method based on coupled mode equation. The wave peak,
transmission, and dispersion parameters are analyzed to determine the performance of the fiber coupler.
The transmission spectrum showed the wave peaks rise to any increase in the grating length on channel
1 and channel 2. Transmission on channel 1 and channel 2 decreased from the wavelength range of
1.45μm–1.55μm and rised in the range of 1,55μm–1,65μm for each increment in length of grating. The
dispersion showed the zero dispersion at specific wavelength for each increase in length of grating. This
component can be applied for controlling information signal in wide range communication.
Trends in High Performance Operation of Electro Absorption Integrated Laser M...Editor IJARCET
For high bit rates and long haul optical
communication systems using a single-mode fiber, a modulator
with low chirp and small size are demanded. An electroabsorption
modulator is very attractive because it has some
advantages of not only low chirp and small size but also the
elimination of polarization control through monolithic
integration with a distributed feedback (DFB) laser. The
modulation bandwidth of traditional lumped electro-absorption
modulators (EAMs) is usually limited by the RC time constant,
but the effective resistance R and capacitance C are not easily
extracted for advanced device geometries. This paper has
presented the important transmission characteristics of electrooptic
absorption modulators such as transmission performance
efficiency, insertion loss, extinction ratio, , over wide range of the
affecting parameters.
DESIGN OF RECTANGULAR PATCH ANTEENA USING METAMATERIAL SUBSTRATEPrateek Kumar
Dissertation part-1 presentation on design of rectangular patch antenna using metamaterial substrate by Prateek Kumar from RUSTAMJI INSTITUTE OF TECHNOLOGY BORDER SECURITY FORCE TEKANPUR GWALIOR (M.P).
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Performance Investigation and Enhancement of Fiber Bragg Gratingfor Efficient...IOSRJECE
In this paper, the performance of various windowfunctions for Fiber Bragg Grating Sensor (FBGS)is investigated and evaluated in order to get optimized reflection spectrum with high reflectivity and an efficient side lobe suppression for efficient sensing measurement applications.For this purpose, a wide range of design parameters which include grating length and refractive index modulation amplitudehas been chosen to evaluate the sensor design. The performances of the different windowfunctions have been then compared in terms of reflectivity, full width half maximum bandwidth (FWHM), and sidelobe level(SLL) so as to get the most suitable design parametersto be used for sensing measurement.The simulation results presented in this paper show the effectiveness of the optimizedFBG sensor, which can be further implemented for high performance sensing applications.
Profile of Single Mode Fiber Coupler Combining with Bragg GratingTELKOMNIKA JOURNAL
This paper describes a numerical experiment of design and operation of a fiber coupler between
single mode fiber and fiber Bragg grating (FBG). Both components are coupled depending with optical
waveguide and source parameters. A characterization of fiber coupler is simulated by varying long grating
of 10 mm to 60 mm using transfer matrix method based on coupled mode equation. The wave peak,
transmission, and dispersion parameters are analyzed to determine the performance of the fiber coupler.
The transmission spectrum showed the wave peaks rise to any increase in the grating length on channel
1 and channel 2. Transmission on channel 1 and channel 2 decreased from the wavelength range of
1.45μm–1.55μm and rised in the range of 1,55μm–1,65μm for each increment in length of grating. The
dispersion showed the zero dispersion at specific wavelength for each increase in length of grating. This
component can be applied for controlling information signal in wide range communication.
Trends in High Performance Operation of Electro Absorption Integrated Laser M...Editor IJARCET
For high bit rates and long haul optical
communication systems using a single-mode fiber, a modulator
with low chirp and small size are demanded. An electroabsorption
modulator is very attractive because it has some
advantages of not only low chirp and small size but also the
elimination of polarization control through monolithic
integration with a distributed feedback (DFB) laser. The
modulation bandwidth of traditional lumped electro-absorption
modulators (EAMs) is usually limited by the RC time constant,
but the effective resistance R and capacitance C are not easily
extracted for advanced device geometries. This paper has
presented the important transmission characteristics of electrooptic
absorption modulators such as transmission performance
efficiency, insertion loss, extinction ratio, , over wide range of the
affecting parameters.
DESIGN OF RECTANGULAR PATCH ANTEENA USING METAMATERIAL SUBSTRATEPrateek Kumar
Dissertation part-1 presentation on design of rectangular patch antenna using metamaterial substrate by Prateek Kumar from RUSTAMJI INSTITUTE OF TECHNOLOGY BORDER SECURITY FORCE TEKANPUR GWALIOR (M.P).
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
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Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
2. Fiber Bragg Grating: Introduction
• The Fiber Bragg Grating (FBG) is a fiber optic passive component
exhibiting basic functional attributes of reflection and filtering.
• FBG’s are relatively simple to manufacture, small in dimension,
low cost and exhibit good immunity changing ambient conditions
and EM radiation.
• FBG’s have replaced bulk optic mirrors & beam splitters in
equipment which increases system stability and portability.
3. Fiber Bragg Grating: Introduction
Telecommunications
Fiber Lasers
Fiber Amplifiers
Fiber Filters
Dispersion Compensators
Optical Fiber Phase Conjugator
WDM
– Multiplexers
– Demultiplexers
Sensors
Strain Sensors
Temperature Sensors
Chemical Sensors
Accelerometers
FBG’s are commercially used in the areas of Telecommunications and Sensors:
4. Fiber Bragg Grating: Theory
1978 – Hill et. all
• Phenomenon of photosensitivity in optical
fibers
• Exposed Ge-doped core fibers to intense
light at 488 or 514 nm
• Induced permanent refractive index changes
to the core.
5. Fiber Bragg Grating: Theory
• FBG is a longitudinal periodic variation of the index of
refraction in the core of an optical fiber.
• The spacing of the variation is determined by the
wavelength of the light to be reflected.
Bragg
Bragg
6. Fiber Bragg Grating: Theory
The Bragg Condition is the result of two requirements:
1. Energy Conservation: Frequency of incident radiation and reflected radiation is the
same.
2. Momentum Conservation: Sum of incident wave vector and grating wave vector
equal the wave vector of the scattered radiation. K + ki = kf
The resulting Bragg Condition is: B = 2L neff
• The grating reflects the light at the Bragg wavelength (B)
• B is a function of the grating periodicity (L) and effective index (neff).
• Typically; B= 1.5 mm, L = 0.5mm
7. Fiber Bragg Grating: Theory
• The spectral component reflected (not transmitted) typically has a bandwidth of 0.05 –
0.3 nm.
A general expression for the approximate Full Width Half Maximum
bandwidth of a standard grating is given by (S = grating parameter (.5 to
1), N = numbers of grating pains):
Δλ =λ B S( (Δn/2n0)2 + (1/N)2 )1/2
1570 1572 1574 1576 1578
-40
-30
-20
-10
0
Loss
in
dB
Wavelength in nm
Reflection
Transmission
8. Fiber Bragg Grating: Theory
• The shift in Bragg Wavelength with strain and temperature can be
expressed using:
DB = 2nL({1-(n2/2)[P12 – n(P11 + P12)]}e
+ [a + (dn/dT)/n]DT
Where:
e = applied strain
Pi,j = Pockel’s coef. of the stress-optic tensor
n = Pisson’s ratio
a = coef. of thermal expansion
DT = temperature change
[P12 – n(P11 + P12)] ~ 0.22
• The shift in Bragg Wavelength is approximately linear with
respect to strain and temperature.
9. Fiber Bragg Grating: Theory
• The measured strain response at a constant
temperature is found to be:
(1/B)dB/ de = 0.78 x 10-6me-1
• Sensitivity Rule of thumb at B = 1300nm:
0.001nm/me
10. Fiber Bragg Grating: Theory
• The measured temperature response at a
constant strain is found to be:
(1/B)dB/ dT = 6.67 x 10-6 oC-1
• Sensitivity Rule of thumb at B = 1300nm:
0.009nm/ oC
11. Fiber Bragg Grating: Theory – Blazed Grating
• Bragg grating planes are tilted at an angle to the fiber axis.
• Light which otherwise would be guided in the fiber core, is coupled
into the loosely bound, guided cladding or radiation modes.
• The bandwidth of the trapped out light is dependent on the tilt angle of
the grating planes and the strength of the index modulation.
• As shown above, the vector diagram is a result of the conservation of
momentum and conservation of energy requirement. The results of
applying the law of cosines yealds: Cos(θb) = ׀K׀/2v
12. Fiber Bragg Grating: Theory – Chirped Grating
• Bragg grating has a monotonically varying period as illustrated above.
• These gratings can be realized by axially varying either the period of
the grating or the index of refraction of the core or both.
• The Bragg Condition becomes: λB = 2neff(z)Λ(z)
• The simplest type of chirped grating is one which the grating period
varies linearly with axial length: Λ(z) = Λ0 + Λ(z)
13. Fiber Bragg Grating: Manufacturing
1989 Meltz et. all.
• Grating written into core by holographic
side exposure method
• Exposure with two beam interference
pattern of UV light at 244nm
• Focal spot is approx. rectangular, 4mm L X
125 mm W.
16. Fiber Bragg Grating: Manufacturing
Novel interferometer
technique using a right
angled prism.
Inherently more stable -
because beams are
perturbed similarly by
any prism vibration.
17. Fiber Bragg Grating: Manufacturing
Phase Mask
Technique.
• UV is diffracted into –1,0,1
orders by relief grating.
• Input mask is wavelength
specific.
• Different B require
different phase masks.
18. Fiber Bragg Grating: Manufacturers
Manufacturers:
• Advanced Optics Solutions GMBH
• Blue Road Research
• 3M Optical OEM Systems
• Alcatel Optronics
• Boeing
• Gould Fiber Optic
• MPB Communications
• OZ Optics Limited
• TeraXion Inc.
• Oxford Lasers Inc.
• Thorlabs Inc.
22. Fiber Bragg Gratings - Application
Mach-Zehnder interferometric Band Pass Filter:
• This arrangement has two identical FBG’s.
• The relative phases of the two transmitted signals is adjusted to maximize the output
from either port 3 or 4 and thus avoiding the 3-db loss of the couplers.
• This arrangement is difficult to manufacture because the performance of the filter is
strongly affected by the spectral characteristics of the two couplers. Also affecting
the filter performance is any imbalance int the power splitting of the couplers or the
relative phases of the signals.
23. Fiber Bragg Gratings - Application
Chirped Grating used for Dispersion Compensation:
• The operating principle is that the grating reflects different wavelength components
of the signal from different sections along the grating.
• As shown below, short wavelengths are reflected first at the near end and longer
wavelengths are reflected at a later time at the far end of the grating.
• Shown below is a simple expression for the group delay dispersion of a linear chirped
grating of length L.
24. Fiber Bragg Gratings - Application
Chirped Grating used for Dispersion Compensation:
• Shown below is a system which transmits a 2 pico-second pulse which is
compensated using a linearly chirped Bragg grating.
• Shown to the lower right is a graph of the compensated and uncompensated
signal.
Other more complicated grating structures are avaliable. For
example cubic dispersion compensation is important in long
distance, high bit rate transmission systems.
25. Fiber Bragg Gratings - Application
Mach-Zehnder DWM – Multiplexer / Demultiplexer:
• This is the Mach-Zehnder arrangement for a WDM application.
Extraction of channel λk Insertion of channel λk
26. Fiber Bragg Gratings - Application
Frustrated Coupler Drop Add Multiplexer:
• This is composed of a mismatched coupler with a Bragg Grating written into one of
the cores.
• Power would not normally be transferred due to the mismatch of the core. With the
Bragg grating, power transfer of the guided mode from port 1 to port 4 can happen if
the sum of the propagation constants of the LP01 modes of each core satisfies the
Bragg condition: (β01(λ12,1) +β01(λ12,2)) = 2Π/Λ
• This cross coupling transfers the guided optical power at λ12 in core 1 into back
propagating optical power in core 2.
27. Fiber Bragg Gratings - Application
Chemical Sensor:
• FBG is blazed into the core at a tilt angle y.
• The FBG Tap radiates a beam out of the core and cladding at an
angle gB.
28. Fiber Bragg Gratings - Application
Chemical Sensor (Continued):
• FBG Tap excites fluorescent layer which in turn emits
light which is in turn collected by the core (f1).
29. Fiber Bragg Gratings – Application, WDM
• In WDM, each FBG sensor is assigned a
portion of the source spectrum.
• Enables quasi-distributed sensing of strain,
temperature, chemical, etc….
• No. of FBG is a function of:
– Source profile width
– Grating operational bandwidth
30. Fiber Bragg Gratings – Application, WDM
• Approx 20 strain sensors can be
multiplexed along a single fiber (peak
strains of +1000me)
32. Fiber Bragg Gratings – References
Othonos, Andreas and Kalli, Kyriacos, “Fiber Bragg Gratings – Fundamentals and Applications in Telecommunications and
Sensing”, Artech House, Inc, 1999.
Hill, K.O., et al., “Photosensitivity in Optical Fiber Waveguides: Application to Reflection Filter Fabrication,” Appl. Phys.
Letter, Vol.32 (647-651) 1978.
Kersey, Alan D., et al., “Fiber Grating Sensors,” Journal of Lightwave Technology, Vol. 15, No. 8, August 1997.
Maher, M.H. and E.G. Nawy, “Evaluation of Fiber Optic Bragg Grating Strain Sensor in High Strength Concrete Beams,”
Fiber Optic Sensors for Construction Materials and Bridges, pp. 120-133, Farhad Ansari, editor, Technical Publishing
Company, Inc., 1998.
Pallas-Areny, R. and J.G. Webster, Sensors and Signal Conditioning, second Ed., John Wiley & Sons, Inc., 2001.
Meltz, G., W.W. Morey and W.H. Glenn, “Formation of Bragg Gratings in Optical Fibers by a Transverse Holographic
Method,” Opt. Lett, 14, (823-825) 1989.
Webster, J.G., The Measurement Instrumentation and Sensors Handbook, RC Press, 1999.
http://www.photonics.com/directory/bg/xq/asp/url.viewcat/bgpsa.30125/qx/categories.html
http://www.aos-fiber.com/