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PDF Design Optical BPF Using Double Clad Fiber MZI for Free Space Optical Communication: Mohanad G. Khamees , Tahreer S. Mansour*
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Abstract: A novel design of Mach Zehnder Interferometer (MZI) in terms of using special type of optical fiber that has double clad with graded distribution of the refractive index that can be easily implemented practically was suggested and simulated in this work. The suggested design is compact, rapid, and is simple to be modified and tested. The simulated design contains a MZI of 1546.74 nm of central wavelength that is constructed using special type of double clad optical fiber that has two different numerical apertures. The first aperture will supply single mode propagation via its core, while the second numerical aperture supports a zigzag wave propagation (multimode) in the first clad region. The interferometer’s sensing arm (double clad fiber) was etched using 40% Hydro-Fluoric (HF) acid to achieve three different fiber diameters, which are ( 84, 72, 54 ) µm with ( 5 ) cm length. The simulation programs Optiwave version 15 and Optigrating version 4.2.2 were used to simulate the setup and to acquire the readings for the three durations of etching (10, 20, and 30) min, and also for the case of no etching at all. The obtained results show that the simulated setup can be used efficiently to test which one of the etching cases has the highest effect on the performance of the overall system, specifically when it comes to spectrum bandwidth, signal amplitude, and received power.

 

The simulated design contains a MZI of 1546.74 n. meter of central reflection wavelength that is constructed from different types of optical fibers. The used Double Clad (DC) optical fiber diameter was reduced in 3 steps as if it was etched using Hydro-Fluoric (HF) acid to achieve three additional different diameters, which are (84, 72, 54) µ. meters in addition to the default 125 µ. meters.

 

The simulation programs (Optiwave and Optigrating) were used to simulate the setup and to acquire the readings for the three durations of etching (10, 20, and 30) min, and also for the case of no etching at all. The obtained results show that the simulated setup can be used efficiently to test which one of the etching cases has the highest effect on the performance of the overall system, specifically when it comes to spectrum bandwidth, signal amplitude, and received power.

 

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Publication Date
Sun Sep 15 2019
Journal Name
Al-academy
Tourist Resting Units and their Design Methods in the Iraqi Marshlands: هدى محمود عمر -لقاء غازي حمد منصور
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    The study dealt with the design of tourist resting units in the Iraqi Marshes in contemporary design methods while preserving the heritage. The first chapter contained the research problem which is the important event of the inclusion of the Marshes in the World Heritage List. This research is important because it aims to develop the tourist reality of the Marshlands. The second chapter dealt with three sections the first of which is tourism in the marsh environment, the second one dealt with the structure of tourist space and the third dealt with the design methods of the tourist resting units in the Iraqi marshes.

The most important results of the research are the following: the sample models have taken desig

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Publication Date
Mon Jun 01 2009
Journal Name
Al-khwarizmi Engineering Journal
Simulation of Free Convection from an Inclined Heated Thin Plate in a Square Enclosure
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Simulation of free convection heat transfer in a square enclosure induced by heated thin plate is represented numerically. All  the enclosure walls have constant temperature lower than the plate’s temperature. The flow is assumed to be two-dimensional. The discretized equations were solved stream function, vorticity, and energy equations by finite difference method using explicit technique and Successive Over- Relaxation method. The study was performed for different values of Rayleigh number ranging from 103 to 105 for different angle position of heated thin plate(0°, 45°, 90°). Air was chosen as a working fluid (Pr = 0.71). Aspect ratio of center of plate to the parallel left wall A2

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Publication Date
Wed Jun 11 2003
Journal Name
Iraqi Journal Of Laser
Q- Switched Nd:YAG Laser Annealing of Phosphorus Diffused Silicon Photodiodes
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Improvement of optoelectrical characteristics of phosphorus diffused silicon photodiodes by Q-switched Nd:YAG laser pulses was investigated. Laser pulses have dissolved the precipitation of phosphorus resulted during thermal diffusion process. The experimental data show that responsivity higher than (0.32 A/W) at 850 nm can be achieved after laser annealing with (1.5 MW/cm2) for 6 shots.

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Publication Date
Tue Dec 12 2017
Journal Name
Al-khwarizmi Engineering Journal
Design a Vegetative Filter Strips Length Using VFSMOD_W Model for Reducing Sediments and Pesticides
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 Abstract 

The vegetative filter strips (VFS) are a useful tool used for reducing the movement of sediment and pesticide in therivers. The filter strip’s soil can help in reducing the runoff volume by infiltration. However, the characteristics of VFS (i.e., length) are not recently identified depending on the estimation of VFS modeling performance. The aim of this research is to study these characteristics and determine acorrelation between filter strip length and percent reduction (trapping efficiency) for sediment, water, and pesticide. Two proposed pesticides(one has organic carbon sorption coefficient, Koc, of 147 L/kg which is more moveable than XXXX, and another one

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Publication Date
Sun Apr 17 2016
Journal Name
Al-academy
Optical patterns and aesthetic values in the halls of events: رواء مصطفى خلف
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current research Cares about study patterns of optical and aesthetic values in the halls of occasions (weddings) because of their importance in providing an atmosphere of joy. The problem was through the study of light and its impact on the receiver and found a researcher that interior spaces allocated to the halls inappropriate in terms of functional and aesthetic so necessitated the need to study this phenomenon in order to be addressed through the study of light and its impact on the users of those spaces where research aims to current detection properties patterns optical in the internal spaces of the halls and identify some of the aesthetic values of the lighting for the interior spaces.The search consists of four chapters, the firs

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Publication Date
Sat Sep 21 2013
Journal Name
Nonlinear Dynamics
BER performance enhancement for secure wireless optical communication systems based on chaotic MIMO techniques
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Publication Date
Sun May 14 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
A New Design of Fractal Optical Modulation
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In this paper it was designed a new fractal optical modulation by using a new iteration of fractal function, the result was analyzed by MTF evaluation, and it compared with results of normal optical modulation.

The normal and fractal optical modulator is a circular disc which has a radius R=9cm, both of them consist of twenty sectors, ten sectors are opaque and the other ten sectors are transmitted for the light.

      The fractal optical modulator contains two patterns, the pattern two can be used to detect the target, and pattern one can be used to lock the target

The best similarity of MTF behavior for normal and fractal Reticle was evaluating the power transparent depends on the size o

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Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Design and Study of Fractal Optical Modulator for Infrared Transmitted Signal
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The optical modulator was designed by using iterated function

systems (IFSs) by IFS Construction Kit program. The modulator was inserted into the optical system using ZEMAX optical design program. In this program, it is assumed that the modulator is made from one of Ø¢ the infrared transmitting materials. Eight materials at room temperature were used in this study; these are IRTRAN materials, Si, and Ge for the range of 3-9 l-lm.

Systems were evaluated and analyzed by using different criteria,

including spot diagram, modulation transfer function, and point spread function. The effect of optical modulator change with the chang of Ø¢ its material results in focusing of functions and frequencies as requ

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Planner And Development
The Transitions in Contemporary Urban Space
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It is the dynamic tension between the relatively fixed built environment and the constantly changing in social life that determines the nature of urban spaces belonging to different historical periods, and considered as a tool for diagnosing transformations in urban spaces, that’s why, the characteristics of urban space became unclear between positive spaces and negative spaces, so emerged the need to study contemporary urban space belonging to the current period of time and show the most important transformations that have occurred in contemporary urban space to reach urban spaces that meet the current  life requirements. Therefore, the research dealt with a study of the characteristics of contemporary urban space and the most pr

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Publication Date
Fri Jan 01 2021
Journal Name
Handbook Of Polymer Nanocomposites For Industrial Applications
Polyaniline-graphite nanocomposite based modified cladding optical fiber gas sensors
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