Abstract: Fiber Bragg Grating (FBG) structure is an periodically modulated optical fiber. It acts as a selective filter of wavelength whose reflected peak is called Bragg wavelength and it depends on the period of the fiber and the refractive index. The simulation of FBG is based on solving the Coupled Mode Theory equation by using the Transfer Matrix Method which is carried out using MATLAB. It is found that spectral reflectivity is shifted when the change of temperature and strain is uniform. Under non-uniform temperature or strain perturbation, the spectrum is both shifted and destroyed. In case of transverse loading, reflectivity spectrum is split into two peaks, the first is specific to X axis, and the second belongs to Y axis. FBGs are used in civil engineering to detect perturbations applied to buildings.
Abstract: In this work, a practical study on a commissioned Giga Passive Optical Network (GPON) fiber to the home access network in Kuwait is presented. The work covers the framework of the conceptual design of the deployed Passive Optical Networks (PONs), access network, optical fiber cable network distribution, technologies, and standards. The work also describes methodologies applied by system engineers for design of Optical Network Terminals (ONTs) and Optical Line Terminals (OLTs) transceivers with respect to the distance, operating wavelengths, splitting ratios. The results have demonstrated and justified the limitation of transmission distance of a PON link in Fiber to The Premises (FTTP) to not exceed 20 km. Optical Time Domain Reflector (OTDR) test has been carried for this project to confirm compliance with International Telecommunication Union (ITU) specifications regarding the total length of the deployed optical cable, total loss in dB, and loss per km in dB/km with respect to the operating wavelengths. OTDR test results with traces for segments of implemented fiber network will be provided and discussed.
Abstract: A mathematical model for an optical-fiber communication channel is developed which results in an expression that calculates the throughput and loss of the corresponding link. The data are assumed to be transmitted by using of separate photons with different polarizations. The derived model also shows the dependency of data throughput with length of the channel and depolarization factor. It is observed that absorption of photons affects the throughput in a more intensive way in comparison with that of depolarization. Apart from that, the probability of depolarization and the absorption of radiated photons are obtained.
Abstract: Measurement and monitoring of temperature, humidity and strain variation are very requested in great fields and areas such as structural health monitoring (SHM) systems. Currently, the use of fiber Bragg grating sensors (FBGS) is very recommended in SHM systems due to the specifications of these sensors. In this paper, we present the theory of Bragg sensor, therefore we try to measure the efficient variation of strain, temperature and humidity (SV, ST, SH) using Bragg sensor. Thus, we can deduce the fundamental relation between these parameters and the wavelength of Bragg sensor.
Abstract: The use of optical technologies in the
telecommunications has been increasing due to its ability to transmit
large amounts of data over long distances. However, as in all systems
of data transmission, optical communication channels suffer from
undesirable and non-deterministic effects, being essential to know the
same. Thus, this research allows the assessment of these effects, as
well as their characterization and beneficial uses of these effects.
Abstract: Wavelength Division Multiplexing (WDM)
technology is the most promising technology for the proper
utilization of huge raw bandwidth provided by an optical fiber. One
of the key problems in implementing the all-optical WDM network is
the packet contention. This problem can be solved by several
different techniques. In time domain approach the packet contention
can be reduced by incorporating Fiber Delay Lines (FDLs) as optical
buffer in the switch architecture. Different types of buffering
architectures are reported in literatures. In the present paper a
comparative performance analysis of three most popular FDL
architectures are presented in order to obtain the best contention
resolution performance. The analysis is further extended to consider
the effect of different fiber non-linearities on the network
Abstract: The analytical bright two soliton solution of the 3-
coupled nonlinear Schrödinger equations with variable coefficients in
birefringent optical fiber is obtained by Darboux transformation
method. To the design of ultra-speed optical devices, Soliton
interaction and control in birefringence fiber is investigated. Lax pair
is constructed for N coupled NLS system through AKNS method.
Using two-soliton solution, we demonstrate different interaction
behaviors of solitons in birefringent fiber depending on the choice of
control parameters. Our results shows that interactions of optical
solitons have some specific applications such as construction of logic
gates, optical computing, soliton switching, and soliton amplification
in wavelength division multiplexing (WDM) system.
Abstract: This paper reports on the response of a fiber-optic
sensing probe to small concentrations of hydrogen peroxide (H2O2)
vapor at room temperature. H2O2 has extensive applications in industrial and medical
environments. Conversely, H2O2 can be a health hazard by itself. For
example, H2O2 induces cellular damage in human cells and its
presence can be used to diagnose illnesses such as asthma and human
breast cancer. Hence, development of reliable H2O2 sensor is of vital
importance to detect and measure this species. Ferric ferrocyanide, referred to as Prussian Blue (PB), was
deposited on the tip of a multimode optical fiber through the single
source precursor technique and served as an indicator of H2O2 in a
spectroscopic manner. Sensing tests were performed in H2O2-H2O
vapor mixtures with different concentrations of H2O2. The results of sensing tests show the sensor is able to detect H2O2
concentrations in the range of 50.6 ppm to 229.5 ppm. Furthermore,
the sensor response to H2O2 concentrations is linear in a log-log scale
with the adjacent R-square of 0.93. This sensing behavior allows us
to detect and quantify the concentration of H2O2 in the vapor phase.
Abstract: This paper presents development results of usage of
C-OTDR monitoring systems for rail traffic management. The COTDR
method is based on vibrosensitive properties of optical fibers.
Analysis of Rayleigh backscattering radiation parameters changes
which take place due to microscopic seismoacoustic impacts on the
optical fiber allows to determine seismoacoustic emission source
positions and to identify their types. This approach proved successful
for rail traffic management (moving block system, weigh- in-motion
Abstract: We have designed wavelength conversion based on
four wave mixing in an optical fiber at 10 Gb/s. The power of
converted signal increases with increase in signal power. The
converted signal power is investigated as a function of input signal
power and pump power. On comparison of converted signal power at
different value of input signal power, we observe that best converted
signal power is obtained at -2 dBm input signal power for both up
conversion as well as for down conversion. Further, FWM efficiency,
quality factor is observed for increase in input signal power and
optical fiber length.
Abstract: This paper presents development results of the method
of seismoacoustic activity monitoring based on usage vibrosensitive
properties of optical fibers. Analysis of Rayleigh backscattering
radiation parameters changes, which take place due to microscopic
seismoacoustic impacts on the optical fiber, allows to determine
seismoacoustic emission sources positions and to identify their types.
Results of using this approach are successful for complex monitoring
Abstract: In this paper, we have compared and analyzed the
electroabsorption properties between with and without excitonic
effect bulk in high purity GaAs spatial light modulator for optical
fiber communication network. The eletroabsorption properties such
as absorption spectra, change in absorption spectra, change in
refractive index and extinction ration has been calculated. We have
also compared the result of absorption spectra and change in
absorption spectra with the experimental results and found close
agreement with experimental results.
Abstract: We model and simulate the combined effect of fiber
dispersion and frequency chirp of a directly modulated high-speed
laser diode on the figures of merit of a non-amplified 40-Gbps optical
fiber link. We consider both the return to zero (RZ) and non-return to
zero (NRZ) patterns of the pseudorandom modulation bits. The
performance of the fiber communication system is assessed by the
fiber-length limitation due to the fiber dispersion. We study the
influence of replacing standard single-mode fibers by non-zero
dispersion-shifted fibers on the maximum fiber length and evaluate
the associated power penalty. We introduce new dispersion
tolerances for 1-dB power penalty of the RZ and NRZ 40-Gbps
optical fiber links.
Abstract: Viscous heating becomes significant in the high speed
resin coating process of glass fibers for optical fiber manufacturing.
This study focuses on the coating resin flows inside the capillary
coating die of optical fiber coating applicator and they are numerically
simulated to examine the effects of viscous heating and subsequent
temperature increase in coating resin. Resin flows are driven by fast
moving glass fiber and the pressurization at the coating die inlet, while
the temperature dependent viscosity of liquid coating resin plays an
important role in the resin flow. It is found that the severe viscous
heating near the coating die wall profoundly alters the radial velocity
profiles and that the increase of final coating thickness by die
pressurization is amplified if viscous heating is present.
Abstract: A simple microstructure optical fiber design based on an octagonal cladding structure is presented for simultaneously controlling dispersion and leakage properties. The finite difference method with anisotropic perfectly matched boundary layer is used to investigate the guiding properties. It is demonstrated that octagonal photonic crystal fibers with four rings can assume negative ultra-flattened dispersion of -19 + 0.23 ps/nm/km in the wavelength range of 1.275 μm to 1.68 μm, nearly zero ultra-flattened dispersion of 0 ± 0.40 ps/nm/km in a 1.38 to 1.64 μm, and low confinement losses less than 10-3 dB/km in the entire band of interest.
Abstract: The evolution of silica optical fiber strength aged in cetyltrimethylammonium chloride solution (CTAC) has been investigated. If the solution containing surfactants presents appreciable changes in physical and chemical properties at the critical micelle concentration (CMC), a non negligible mechanical behavior fiber change is observed for silica fiber aged in cationic surfactants as CTAC which can lead to optical fiber reliability questioning. The purpose of this work is to study the mechanical behavior of silica coated and naked optical fibers in contact with CTAC solution at different concentrations. Result analysis proves that the immersion in CTAC drastically decreases the fiber strength and specially near the CMC point. Beyond CMC point, a small increase of fiber strength is analyzed and commented.
Abstract: The purpose of this study is to design a portable virtual
piano. By utilizing optical fiber gloves and the virtual piano software
designed by this study, the user can play the piano anywhere at any
time. This virtual piano consists of three major parts: finger tapping
identification, hand movement and positioning identification, and
MIDI software sound effect simulation. To play the virtual piano, the
user wears optical fiber gloves and simulates piano key tapping
motions. The finger bending information detected by the optical fiber
gloves can tell when piano key tapping motions are made. Images
captured by a video camera are analyzed, hand locations and moving
directions are positioned, and the corresponding scales are found. The
system integrates finger tapping identification with information about
hand placement in relation to corresponding piano key positions, and
generates MIDI piano sound effects based on this data. This
experiment shows that the proposed method achieves an accuracy rate
of 95% for determining when a piano key is tapped.
Abstract: Fiber optic sensor technology offers the possibility of
sensing different parameters like strain, temperature, pressure in
harsh environment and remote locations. these kinds of sensors
modulates some features of the light wave in an optical fiber such an
intensity and phase or use optical fiber as a medium for transmitting
the measurement information.
The advantages of fiber optic sensors in contrast to conventional
electrical ones make them popular in different applications and now a
day they consider as a key component in improving industrial
processes, quality control systems, medical diagnostics, and
preventing and controlling general process abnormalities.
This paper is an introduction to fiber optic sensor technology and
some of the applications that make this branch of optic technology,
which is still in its early infancy, an interesting field.
Abstract: In this work we report on preliminary analysis of a novel optoelectronic gas sensor based on an optical fiber integrated with a tetrakis(4-sulfonatophenyl)porphyrin (TPPS) thin film. The sensitive materials are selectively deposited on the core region of a fiber tip by UV light induced deposition technique. A simple and cheap process which can be easily extended to different porphyrin derivatives. When the TPPS film on the fiber tip is exposed to acid and/or base vapors, dramatic changes occur in the aggregation structure of the dye molecules in the film, from J- to H-type, resulting in a profound modification of their corresponding reflectance spectra. From the achieved experimental results it is evident that the presence of intense and narrow band peaks in the reflected spectra could be monitored to detect hazardous vapors.
Abstract: This paper solves the Non Linear Schrodinger
Equation using the Split Step Fourier method for modeling an optical
fiber. The model generates a complex wave of optical pulses and
using the results obtained two graphs namely Loss versus
Wavelength and Dispersion versus Wavelength are generated. Taking
Chromatic Dispersion and Polarization Mode Dispersion losses into
account, the graphs generated are compared with the graphs
formulated by JDS Uniphase Corporation which uses standard values
of dispersion for optical fibers. The graphs generated when compared
with the JDS Uniphase Corporation plots were found to be more or
less similar thus verifying that the model proposed is right.
MATLAB software was used for doing the modeling.