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تحليل وبرمجة الستلايت ذو تقنيات متعدد الوصول == Analysis and Simulation of Satellite Multiple Access Techniques

Author name: سارة خماس جوي العقابي
Supervisor name: رعد سامي فياض | صديق يوسف امين
Degree: Master
Language: English
University location: Baghdad
First pages:

تحليل وتمثيل معادل قرار استرجاع مطور == Analysis and Simulation of a Modified Decision Feedback Equalizer

Author name: اسامة محمد سعيد
Supervisor name: سركون نامق عبد الله
Degree: Master
Language: English
University location: Baghdad
First pages:

معالجة الاختلال في I/Q انظمة الاتصالات للتقسيم المتعددة المتعامد التردد == Compensation of I/Q Imbalance in OFDM Communication Systems

Author name: بهاء جاسم موسى الجبوري
Supervisor name: رعد سامي فياض
Degree: Master
Language: English
University location: Baghdad
First pages:

الخط المشترك الرقمي تصميمه وتمثيله == DIGITAL SUBSCRIBER LINE: DESIGN AND SIMULATION

Author name: الحمزة طاهر محمد المولاوي
Supervisor name: نصر نافع خميس
Degree: Master
Language: English
University location: Baghdad
First pages:

اعتبار تصميم وتحسين منظومة تجهيز القدرة لقمر اصطناعي

Author name: ديانا عدنان نمرود هيدو
Supervisor name: جابر سلمان عزيز
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم مجهز قدرة ذو نمط مفتاحي لليزر ثنائي اوكسيد الكاربون ذو التهيج المستعرض بالضغط الجوي == DESIGN OF SWITCHED-MODE POWER SUPPLY FOR TEA CO2 LASER

Author name: بلال عصام عبد الرزاق
Supervisor name: مثنى جميل الخشالي
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم وبناء منظومة تعتمد في عملها على كل من منظومة تحديد المواقع العالمية والمنظومة العالمية للاتصالات المتنقلة == DESIGN AND IMPLEMENTATION OF GPS/GSM BASED SYSTEM

Author name: ابراهيم طالب عبد القادر
Degree: Master
Language: English
University location: Baghdad
First pages:

المشفر الالتفافي القابل للبرمجة باستخدام حقل مصفوفات البوابات القابلة للبرمجة == PROGRAMMABLE CONVOLUTIONAL ENCODER USING FPGA

Author name: شهاب احمد عبد الله
Supervisor name: عبد الكريم عبد الرحمن
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم وتحليل الاداء لوصلة راديوية على مستوى خط الرؤية == DESIGN AND PERFORMANCE ANALYSIS OF LINE-OF-SIGHT (LOS) RADIO LINK

Author name: سرمد صفاء سالم
Supervisor name: جابر سلمان عزيز
Degree: Master
Language: English
University location: Baghdad
First pages:

تحليل ومحاكاة هوائي الشرط المستدقة الاسطواني لاقمار الاقرار الفتلي الاصطناعية == ANALYSIS AND SIMULATION OF A CYLINDRICAL MICROSTRIP ANTENNA FOR SPIN-STABILIZED SATELLITES

Author name: لباب علي سلمان
Supervisor name: عباس احمد الشالجي | اسعد مبدر جاسم
Degree: Master
Language: English
University location: Baghdad
First pages:

استجابة المتحسس المتواتر مكانيا لمرور خليط الجسيمات العازلة والموصلة == RESPONSE OF THE SPACE PERIODIC FLOW SENSOR TO DIELECTRIC AND CONDUCTING MIXTURES

Author name: حسام الدين فيصل كوكز المحمدي
Supervisor name: عباس الشالجي
Degree: Master
Language: English
University location: Baghdad
First pages:

تخمين القناة للمنظومات اللاسلكية متعددة المداخل والمخارج والعاملة بتقنية تقسيم وتجميع الترددات المتعامدة باستخدام تقنية نغمة الدليل == MIMO-OFDM WIRELESS CHANNEL ESTIMATION BASED ON PILOT-TONE TECHNIQUE

Author name: فيان سعد قاسم محمد
Supervisor name: رعد سامي فياض
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

نظام اخفاء المعلومات الصوتي المبني على معالجة ا?شاره الرقميه == A Wavelet Based Audio Steganography System

Author name: ريام مجيد زعال
Supervisor name: رجاء الدين عبد خالد
Degree: Master
Language: English
University location: Baghdad
First pages:

تنفيذ مبسط لبروتوكولات القياس والسيطرة عن بعد للاقمار الصناعية باستخدام المصفوفات المبرمجة == Implementation of a Simplified Satellite Telemetry and Telecommand Protocols Using FPGA

Author name: خليل اسماعيل خليل الطائي
Supervisor name: سركون نامق عبد الله
Degree: Master
Language: English
University location: Baghdad
First pages:

تجزئة الحزمة لالغاء الضوضاء المتكيف في تنقية الاشارة الكلامية == Subband Decomposition For Adaptive Noise Cancellation In Speech Enhancement

Author name: حوراء فاضل عبيد
Supervisor name: منال جميل الكندي
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Nowadays speech processing methods are usually implemented in the time or frequency domain. Filter bank can be considered as a divide and conquer approach within signal processing, since large problems are sub - divided into many smaller problems. While filter banks are essential components of speech processing, and in signal processing in general, they will have the focus in present days. An adaptive filter is a filter that self adjusts its transfer function according to its optimizing algorithms. Least mean square algorithm has slow convergence when used with nonstationary signals like speech and it has high computational cost but normalization of step size (or input signal) leads to a useful variant of the LMS algorithm known as the normalized LMS (NLMS) algorithm, which gives better convergence characteristics than the LMS because it uses a variable step - size with respect to the input signal power.To improve the convergence rate and/or computational complexity and also to overcome the disadvantage of a full band adaptive filtering, a structure is illustrated that is subband adaptive filtering; this will converge faster at a lower computational cost for speech and white noise inputs.This research shows most types of subband decomposition structures and makes comparison among them based on their performance to cancel the noise with minimum computational complexity, maximum convergence speed and maximum noise cancellation with lowest delay.Moreover three new hybrid tree configurations or the tree decom - position are proposed to maximize the overall performance of adaptive noisecancellation system.They are given the abbreviations HTPSAF1,HTPSAF2 and HTPSAF3. These three systems use polyphase filter bank that has showed a noticeable increase in the convergence speed and large reduction in the computational complexity due to the lower number of coefficients that can be achieved for the analysis/synthesis filters, which in turn will result in minimum delay in the reconstructed output speech signal.The algorithm of subband decomposition structures has been described theoretically then modeled under MATLAB simulation program using built - in filters and real input signals.

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.

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.

تصميم الكيان المادي وتنفيذ مزيل الضوضاء المتكيف == Hardware Design And Implementation Of Adaptive Noise Canceller

Author name: علي عدنان طالب الاميري
Supervisor name: منال جميل الكندي | ثامر محمد جميل
Degree: Master
Language: English
University location: Baghdad
First pages:
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