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التشوه بالتوافقيات في اشارات التدفق للمتحسس السعوي الحيزي المثبت خارجيا == Harmonic Distortion In The Flow Signals of Externally Mounted Capacitive Spatial Filter

Author name: مروه مالك حسوني
Supervisor name: عباس احمد الشالجي
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: This thesis investigates the performance of some windows on the flow signals that are generated from the planar capacitance spatial filter (PCSF) according to the moving of the solid particle in the channel of the filter. The sensor that operates as non - invasive device for solid flow measurement utilizes the thin wall of a dielectric pipe section as a shielding layer to protect the sensor from erosion, rust and moisture, and to make it more versatile.The finite - difference model equations are solved using successive over relaxation (SOR) methods. The waveforms show that the response of the PCSF is spatially - biased towards particle flowing closer to the plane of sensing electrodes and that the resulting flow signal is non - sinusoidal. The SOR method that is used to compute the PCSF potential fields has been investigated using a mesh of 110 by 32 nodes, and the algorithm was programmed in MATLAB (Release 2013a) using an Intel core ™ i3 PC,CPU processor.To study the effect of the total harmonic distortion (THD) content on the flow signals that are calculated with respect to the fundamental frequency of the power spectrum density through a specific quantitative criterion, this work comprises a comparative study among three types of windows; Hanning, Hamming, and a subOptimal window called the Kaiser window.The effect of particle flying heights, relative permittivity and size on the THD of the flow signal were examined. It was found that theTHD of flow signals at heights closer to the plane of sensing electrodes is high and decreasing gradualy when the particle flying height is far above the sensor. All the three windows used in this work have better suppression of harmonics distortion as compared with unwindowed (raw) flow signal.

طرائق الكشف للتضمين الترددي المتعامد للرابط النازل في نظام تطور طويل الامد (LTE) == Detection Methods For Ofdm Downlink In Long Term Evolution (LTE) System

Author name: اكرم جبار عبد الحسين حسن
Supervisor name: يمان اسماعيل مجيد
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:
Abstract: GPP3 التطور على المدى الطويل (LTE) هو تقنية الجيل الرابع اللاسلكية ذات النطاق العريض. هدفه الرئيسي هو تعزيز الكفاءة الطيفية باستخدام تقنيات التضمين الترددي المتعامد بالتقسيم (OFDM). ومع ذلك، ياتي هذا التحسن في الاداء بزيادة التعقيد الحسابي في اجهزة الاستق | 3GPP Long Term Evolution (LTE) is the fourth generation mobile wireless broadband technology. Its key objective is to enhanced spectral efficiency by using Orthogonal Frequency Division Multiplexing (OFDM) techniques. However, this performance improvement comes at the cost of increased computational complexity in the receiver. The goal of this work is to introduce a detection method that gives a better performance with reasonable computational complexity for LTE mobile communication system. An approximated linear baseband model for the two modulation techniques used by the LTE system (which is the Quadrature Phase Shift Keying (QPSK) and sixteen - level Amplitude Modulation (16 - QAM)) have been derived. Three receivers have been simulated and tested. The three receivers use Least Square (LS) channel estimator. These receivers uses channel compensator, decision feedback equalizer and perturbation algorithm. The LTE communication system has been simulated using MATLAB®7 programming language. The results of the computer simulation show that the perturbation algorithm gives an enhancement in the receiver performance of about 2 dB in different mobile channels than decision feedback equalizer and about 5 dB than channel compensator at the 10 - 3 of BER.

بناء خوارزمية تزامن لانظمة (OFDM) باستخدام معالجة الاشارة الرقمية == Dsp - Based Synchronization Algorithm Implementation For OFDM System

Author name: رائد ستار جبر
Supervisor name: محمود عبد القادر عبد الستار
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: تعدد الارسال للتردد بالتقسيم المتعامد (OFDM) هو مفتاح تمكين التكنولوجيا لمعظم انظمة الاتصالات اللاسلكية الحالية ذات معدل نقل البيانات العالي. والميزة الرئيسية للـ (OFDM) مقارنة بالطرق التقليدية هو انه يحول القناة ذات النطاق العريض الى قنوات فرعية ضيقة متو | Orthogonal Frequency Division Multiplexing (OFDM) is the key enabling technology for most current high data - rate wireless communication systems. The primary advantage of OFDM over conventional schemes is that it converts a wideband channel into parallel narrowband sub - channels allowing relatively simple channel estimation and frequency domain equalization. It is as an effective technique for coping with channel impairments like multipath propagation and Inter Symbol Interference (ISI) by making use of an appropriate cyclic prefix. One of the major drawbacks of OFDM is that it is more sensitive to synchronization errors than its single carrier counterparts. This thesis describes a real - time implementation of a timing and frequency synchronization for OFDM system using MATLAB software Simulink, DSP processor TMS320C6713 and Code Composer Studio (CCS). The hardware interface converts the baseband signal from the PC to the DSP Processor. Basic transmission and reception performances are evaluated in real time using Real Time data Transfer (RTDX). The practical results and performance evaluation of the synchronization algorithms in OFDM system is presented and discussed. The results are plotted for different offsets of CFO and STO with different values of signal to noise ratio. Also the bit error rate (BER) and the mean square error (MSE) of the system is analyzed. The results show that the time offset more effect than frequency offset because of ISI and ICI occurs when time offset occur in the system. The synchronization algorithm is found to be robust for both CFO and STO simultaneously. It can handle offset of about CFO = 500 Hz and STO = 14 samples simultaneously without wasting extra bandwidth. This algorithm used for synchronization more robust for 16QAM compared with 4QAM modulation.

تاثير اللاخطية في الالياف البصرية على اداء نظام تجميع الاطوال الموجية الضوئية المنقسمة باستخدام تقنية الاستقطاب المزدوج لتقسيمات التردد المتعامد الضوئي == Effect of Fiber Nonlinearity On The Performance of WDM Optical Systems Using Dual Polarization CO - OFDM Technique

Author name: بشار مظفر احمد
Supervisor name: رعد سامي فياض
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: The implemented existing high capacity optical networks are based on 50 GHz wavelength - division multiplexing (WDM) channel spacing and carry up to 50 Gb/s data rate per channel. In recent years, there is increasing interest in using dual - polarization (DP) technique to enable future systems with at least 100 Gb/s rate per channel to operate over existing optical networks. The performance of these advanced systems can be enhanced further by using coherent optical orthogonal frequency division multiplexing (CO - OFDM) technique which offers high spectral efficiency and outstanding tolerance of fiber dispersion.This thesis addresses the effect of fiber nonlinear optics on the performance of dual polarization CO - OFDM/WDM system operating with 100 Gb/s per channel. Different modulation formats, namely BPSK, QPSK and 16 - QAM, are used. First, the performance of a single - channel system is investigated in the absence and presence of fiber nonlinearity. The results are compared with those of a conventional (single - polarization) system to identify the key role played by the DP technique. The investigation is then extended to WDM systems incorporating DP - OFDM technique. The results reveal that the effect of fiber nonlinearity can be reduced or cancelled by using optimum transmitter laser power Popt. Further, the value of Popt is a function of transmission distance,number of multiplexed channels, and modulation formats. Popt of - 11, - 12, and - 5 dBm is needed for a ten - channel DP system operating with BPSK, QPSK, and 16 - QAM formats, respectively.Simulation results presented in this thesis are obtained using OptiSystem (version 11.1) which is a commercial software package.

الغاء تداخل المسا ارت التخميني في انظمة الوصول المتعدد باستخدام تقسيم الترميز الواسع الطيف لشبكات الاتصال اللاسلكية == Multipath Interference Cancellation Investigation In Wcdma Communication Networks

Author name: نور محمد خليل
Supervisor name: منال جميل الكندي
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Bit Error Rate (BER) and Bit Energy to Noise Ratio(?????????) performance of the 1 - D RAKE receiver without , with Space Time Transmit Diversity (STTD) and 2 - D RAKE without , with (STTD) and also without and with beamforming for WCDMA over RayleighChannel in presence of Additive White Gaussian Noise (AWGN) channel is demonstrated with purpose of making simulation of m - files developed in Matlab.Results are evaluated in terms of BER and ????????? considering the number of Base Station (BS) transmit antennas (1 - D RAKE and 2 - D RAKE receivers), and the number of RAKE fingers (1 - D RAKE receiver) and the number of Mobile Station (MS) receive antennas (2 - DRAKE receiver). The performance results of 1 - D RAKE and 2 - D RAKE receivers showed that the receivers have satisfactory BER performance and the performance of RAKE receivers is more improved by increasing the number of RAKE fingers, performance is even better when beamforming was applied.The performance results of the three receive diversity of 2 - D RAKE receiver schemes : Selection Combining (SC), Equal Gain Combining (EGC) or Maximal Ratio Combining (MRC)) of 2 - D RAKE showed that there are significant improvements in BER and ?????????performance over the 1 - D RAKE. BER of 10???? can be obtained at ????????? ? 5 dB performance with four fingers of 2 - D RAKE receiver with STTD and beamforming and MRC scheme for five receive antenna elements.

تحسين جودة الصورة التوموغرافية المعاد تركيبها باستخدام خوارزمية التسقيط العكسي المرشحة == Enhancement of Tomographic Image Quality Reconstructed By Filter Backprojection Technique

Author name: دعاء نوفل حازم
Supervisor name: محمد حسين الحياني
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Computed tomography refers to the imaging of slices of an object by exposing them to X - ray in different directions. Measurement of image quality is one of great importance in the field of medical applications. In applications such as CT and MRI scanning, most of the time the quality of reconstructed image is assessed qualitatively by radiologist or domain experts which are purely subjective evaluation.The FBP algorithm produces excellent quality and high performance reconstruction compared with other reconstruction algorithms. This thesis presents different projection types (fan beam geometry, and cone beam geometry) for the image reconstruction, the geometries are calculated analytically by specified 2D head phantom for fan beam and 3D head phantom for single slice spiral cone beam geometry with different ranges covering angle.In the thesis the FBP algorithm was applied with the fan beam and single slice geometries. Different types of filters (Hann, Hamming, Kaiser, Cosine, Ram - Lak, and Gaussian) are used in the algorithm and a new window filter is proposed in the algorithm. Comparisons are made between the new window and different common windows by quality measurement to get a reconstructed image with high quality and high performance suitable for the implementation of the FBP.A computer programs has been designed, written, and implemented in this work using MATLAB 7.1, for fan beam and single slice projections. Good results of quality and performance were obtained for the tomographic reconstructed image from its projection on CT scanner.

نظام الاتمتة المنزلية مبني على اساس شبكة المتحسسات اللاسلكية == Home Automation System Based On Wireless Sensor Network

Author name: محمد قاسم شاكر
Supervisor name: اسامة قاسم جمعة
Degree: Master
Language: English
University location: Babylon
First pages:

تصميم منظومة اتصالات ضوئية لاسلكية خارجية اعتمادا على مازج تقسيمات الطول الموجي مع حزمة فائقة العرض == Design Of Outdoor WDM-UWB Based Optical Wireless Communication System

Author name: ياسر خضير عباس
Supervisor name: ابراهيم عبد الله مراداس
Degree: Master
Language: English
University location: Babylon
First pages:

تصميم ودراسة ترانزستور تاثير المجال (معدن - اوكسيد - شبه موصل) بتقنية الزرع الايوني وبابعاد النانوميتر == Design and Study of Ion-Implanted MOSFET’s with Nano meter Dimensions

Author name: فراس نذير عبد القادر
Supervisor name: خالد خليل محمد
Degree: Master
Language: Arabic
University location: Mosul
First pages:

تصميم وتنفيذ نظام واي ماكس ذو المعيار باستخدام حقل المصفوفات القابلة للبرمجة IEEE 802.16d == Design And Implementation Of IEEE 802.16D Wimax Baseband System Using FPGA

Author name: قاسم هادي كريم
Supervisor name: محمود عبد القادر عبد الستار
Degree: Master
University: University of Baghdad
Language: English
University location: Baghdad
First pages:

تصميم وتنفيذ نظام جباية اجور استهلاك الطاقة الكهربائية بالاعتماد على نظام الاتصالات العالمية == Design and Implementation of Electrical Energy Billing System Based on GSM

Author name: احمد محمد مرزة
Supervisor name: محمود شاكر الشمري
Degree: Master
Language: English
University location: Babylon
First pages:

تصميم وتنفيذ نظام العناية الصحية المتنقل في الاسعاف بالاعتماد على شبكة الانترنت == Design and Implementation of Ambulance Mobile Health System Based on Internet

Author name: عبد الله علي جابر الحسيني
Supervisor name: سمير جاسم محمد
Degree: Master
Language: English
University location: Babylon
First pages:

حساب الوثوقية في انظمة الاتصالات اللاسلكية == Reliability Evaluation For Wireless Communication System

Author name: ياسمين عبد الغني اليوزبكي
Supervisor name: اسماعيل محمد جابر
Degree: Master
Language: English
University location: Baghdad
First pages:

تحسين اداء انظمة الاتصالات الخلوية باستخدام MIMO - OFDM == Performance Improvement of Cellular Communication Systems Using MIMO – OFDM

Author name: وسن ممدوح عبد اللطيف التتنجي
Supervisor name: سامي محمد طاهر عبد الموجود
Degree: Master
Language: Arabic
University location: Mosul
First pages:

العلامة المائية السمعية للتطبيقات الطبية اعتمادا على تحويل هجين == Audio Watermarking For Medical Applications Based On Hybrid Transform

Author name: هبة عبد الجليل كزار الاسدي
Supervisor name: اسامة قاسم الذهب
Degree: Master
Language: English
University location: Babylon
First pages:

اتحاد الاحياء تحت انقاض البنايات باستخدام المنطق الضبابي == Detecting Trapped Alive Humans Under Buildings Ruins Using Fuzzy Logic

Author name: نورا هاني شريف عبد العزيز
Supervisor name: محي محمد جاسم العزاوي
Degree: Master
Language: English
University location: Baghdad
First pages:

تنفيذ البنية المادية الرقمية للشبكات العصبية الاصطناعية على شريحة مصفوفة البوابات المبرمجة حقليا (FPGA) باستخدام لغة وصف الكيان المادي (VHDL) == Digital Hardware Implementation of Artificial Neural Network on Field Programmable Gate Array ( FPGA) using VHDL Language

Author name: نور طلال محمود كداوي
Supervisor name: رافد احمد خليل عموري
Degree: Master
Language: Arabic
University location: Mosul
First pages:

تقييم المعالجين or-cfar و And - cfar لنماذج مختلفة من الاشارات غير المرغوب فيها == Evaluation Of AND - CFAR And OR - CFAR Processors Under Different Clutter Models

Author name: نجم عبد الله جازع
Supervisor name: وليد خالد عبد علي
Degree: Master
Language: English
University location: Baghdad
First pages:

Development Of Interprocess Communication Simulation For Distributed SCADA System

Author name: نادية اسماعيل
Supervisor name: sarkout N.Abdulla | Nazar AI rawas
Degree: Master
Language: English
University location: Baghdad
First pages:

محاكاة البصري المتشاكة لتقنية مازج تقسيمات التردد المتعامدة في نظام مازج تقسيمات الطول الموجي == Simulation Of Coherent Optical OFDM In WDM System

Author name: مياسة رزاق عبد علي
Supervisor name: ليث علي عبد الرحيم | ابراهيم عبد الله مرداس
Degree: Master
Language: English
University location: Babylon
First pages:

ارسال البيانات عبر قناة العالية التردد باستخدام تقنية التعدد التقسيمي الترددي المتعامد == HF Data Transmission Using Orthogonal Frequency Division Multiplexing (OFDM)

Author name: مهند عصام عقاب الماضى
Supervisor name: Mahir K. M. Al-Azawi
Degree: Master
Language: English
University location: Baghdad
First pages:

دراسة اداء خوارزميات تحليل المركبات غير المعتمد الخطي في تقنية DS-CDMA == Performance Study Of Linear ICA Algorithms In DS - CDMA Technique

Author name: مفاز محمد عبد جعفر شبر
Supervisor name: ستار بدر سدخان | سمير جاسم محمد
Degree: Master
Language: English
University location: Babylon
First pages:

الاظهار المتكيف للاهداف المتحركة باستخدام معالجة الاشارة الرقمية في الزمن الحقيقي == Real Time Adaptive MTI Using DSP

Author name: محمود احمد محمود الزبيدي
Supervisor name: خليل حسن سيد مرعي | سعد داؤد سليمان الشماع
Degree: Doctorate
Language: English
University location: Mosul
First pages:

تحليل تاثيرات التضخيم الغير خطي في نظام OFDM == Analysis Of Effects Of Non Linearity Amplification In OFDM System

Author name: محمد عبد العالي عبد الكاظم
Supervisor name: ايهاب عبد الرزاق حسين
Degree: Master
Language: English
University location: Babylon
First pages:

تنفيذ الاشارات ذات الترميز التوربوي المكيف في نظم الاتصالات اللاسلكية == Implementation Of Adaptive Turbo Coded Signals For Wireless Communication Systems

Author name: محمد ازهر رزاق
Supervisor name: احمد عبد الكاظم حمد
Degree: Master
Language: English
University location: Babylon
First pages:
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