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منظومة المراقبة والسيطرة لمحطات توليد الطاقة الكهربائية العراقية المبنية على بروتوكول الانترنت == INTERNET PROTOCOL BASED MONITORING AND CONTROL SYSTEM FOR IRAQI POWER GENERATION STATIONS

Author name: سهيل نجم عبيد القيسي
Supervisor name: Nassir N. Khamiss
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad

تصميم وتنفيذ وحدة استخلاص معلومات لقياس القدرة الكهربائية المستهلكة == Design and Implementation of Data Extraction Unit for Consumed Electrical Power Account

Author name: مصطفى حميد صالح
Supervisor name: Jabir S. Aziz
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad

تحسين التغطية للشبكات الخلوية == COVERAGE ENHANCEMENT OF CELLULAR NETWORK

Author name: زيد شاكر كاظم
Supervisor name: جابر سلمان عزيز
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:

تحسين صورة التصوير المقطعي المخروطي عن طريق خوارزميات اعادة بناء الصور == ENHANCEMENT OF CONE-BEAM COMPUTED TOMOGRAPHIC IMAGE BY RECONSTRUCTION ALGORITHMS

Author name: شيماء عبد السلام خزعل
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:

المنضومة الهاتفية العاملة ببروتوكولات الانترنيت مستندة على شبكة رقعة محلية (LAN) == LAN - Based IP Phone Systme

Author name: جيهان صلاح عبد الجبار
Supervisor name: فراس عبد الله | خلدون عطا الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
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.

تحليل الاتصال بين القمر الصناعي والطائرة باستخدام نموذج تعقب الشعاع == Analysis of Satellite - To - Aircraft Communications Using Ray Tracing Model

Author name: علي محمد علي
Supervisor name: جابر سلمان عزيز
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:
Abstract: While the aircraft flying above the earth surface, the signal transmitted from the satellite to the aircraft suffered from changes in it's characteristics at the aircraft receiver's antenna according to many factors affecting the direct and reflected power from the earth surface such as the distance difference, the nature of the earth surface, elevation angle, Doppler shift, etc… This Thesis introduces a proposed algorithm to analyze and simulate the communication link between the Satellite and the aircraft taking into account all the parameters that affect the magnitude of the power and signal characteristics received at the aircraft antenna. The proposed method uses the ray - tracing technique in this simulation to analyze the communication link between the Satellite and aircraft. The simulation developed in this thesis has minimized the error percentage as much as possible taking into account most of the factors that might affect the characteristics of the signal received by the aircraft from the satellite. This simulation considers the free space loss, specular reflection losses, scattering factor, earth curvature effect, etc…,also the simulation takes into account the Doppler effect that caused by the aircraft movements. The simulation measures the received signal strength and fading characteristics of satellite to aircraft communication to determine the effectiveness of communication and to establish parameters which can be useful to the communication system designer in Iraq and the rest of the world. MATLAB® v6.5 used in the simulation as application software, the simulation also applied to MATLAB® v7.0.

تحليل المسار النازل لنظام الاتصال اللاسلكي التكيفي المتعدد المداخل والمخارج والمستخدمين == Analysis of Adaptive Downlink Multiuser Mimo Wireless Communication System

Author name: عمر جبار ابراهیم
Supervisor name: رعد سامي فياض
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:
Abstract: Multiple - input multiple - output (MIMO) wireless communication systems have received significant attention due to their enormous channel capacity potential in rich scattering environment. Such systems need to consider multiuser transmission / reception in their design. This thesis investigates theoretically the ergodic capacity of multiuser MIMO systems operating with adaptive techniques to enhance their performance. The ergodic capacity of multiuser MIMO system is analyzed and simulated for three types of channels : additive white Gaussian noise (AWGN) channel, uncorrelated Rayleigh fading (URF) channel, and semicorrelated Rayleigh fading (SRF) channel. The downlink SRF channel for each user is modeled by assuming that the fading is correlated at the transmitter but uncorrelated at the receiver side. The simulation results are compared to those related to a single - user system and used as a guideline to present an adaptivetechnique to enhance the capacity of MIMO system operating in SRF channel. The adaptive technique is based on a tradeoff between time division multiple access (TDMA) and block diagonalization (BD).Simulation results are presented using MATLAB environment to address the dependence of ergodic capacity of a MIMO communication on various system and channel parameters. The results indicate clearly that the threshold level of angle between users ? employed in the adaptive system must be chosen carefully to maximize the ergodic capacity. The optimum threshold ?th is equal to 24°, 42° and 47°, for angle spread ? = 5°, 50° and 75°, respectively

محاكاة GSM/EDGE وGSM لنظام الاتصالات المتنقلة == Simulation of GSM And GSM/EDGE Mobile Communication Systems

Author name: اسامة علي عبد الله
Supervisor name: رعد سامي فياض
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The introduction of global system for mobile communication (GSM) air interface has undoubtedly created a new area in telecommunications. In view of its extensive use in real world applications, it is highly desirable to further investigate the performance of the GSM system under different operating conditions and environments. Furthermore, there is increasing interest in using high - level modulation to provide enhanced data rate for GSM evolution (EDGE).This thesis investigates the performance of both GSM and GSM/EDGE systems operating in Raleigh fading channel. The results are reported for different models of fading channel in order to describe various environments. A detailed SIMULINK model is developed in MATLAB environment to simulate the GSM system. Furthermore, a MATLAB software package is developed to simulate extensively the EDGE system. Both simulation models are handled to characterize each essential part in these systems. The simulation takes into account channel coding, modulation type, interleaving and burst building, multipath channel effect, channel estimation, and detection process.The simulation results indicate clearly that to achieve a bit error rate (BER) of 1x10P - 5 P in additive white Gaussian noise (AWGN) channel, the signal - to - noise (SNR) ratio should be 5.25, 3.75 and 12.25 dB when GSM, MCS - 1 EDGE (GMSK modulation), and MCS - 7 EDGE (3?/8 - 8PSK modulation) systems are used , respectively. These values are to be compared with R12R.43, R1R0.21 and R2R1.05 dB, respectively, for HT100 - type fading channel. The MSC - 1 system offers the best BER characteristics followed by GSM system. The MCS - 7 offers the worst BER characteristics among the three systems.

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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
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.

محاكاة تضمين تقسيم التردد المتعامد المتعدد المستخدمين المشفر في الخط النازل == Simulation of Coded Multiuser Ofdm Downlink

Author name: دﻧﻴﺎ ﻓﺆاد فاروق النعيمي
Supervisor name: رعد سامي فياض
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The orthogonal frequency division multiple access (OFDMA) scheme adopts orthogonal frequency division multiplexing (OFDM) subcarriers, which are particularly suited for transmition over broadband frequency selection channels, to support multiusers. The scheme considered usually assigns a subset of subcarriers to each user and adopted adaptive techniques for the allocation of available resources/subcarriers according to the channel state information (CSI) estimated at the transmitter using a reverse link. This thesis proposed three coded multiuser OFDM schemes based on spreading the data of each user over all subcarriers without CSI at the transmitter. The idea behind these schemes is to split the OFDM transceiver into two stages : one common to all users while the other consists of identical parallel units with each unit is used to process the data related to an individual user. The two stages are separated by a multiplexer/demultiplexer unit whose position can be chosen to yield different schemes. The three schemes considered here are : user multiplexed scheme, inner coded multiplexing scheme, and mapper multiplexing scheme. The proposed schemes implemented are using MATLAB simulink (version 7) to investigate their performance under different operating conditions related to number of users, Rayleigh fading channel, and serial concatenated codes. The results are compared with those related to two conventional schemes, subcarrier mapping scheme and outer coded multiplexing scheme. The simulation results indicate that the proposed user multiplexing scheme may offer performance as high as that offered by the conventional outer coded multiplexing scheme but with reduced number of equipments.

تهيئة حاسوبية لموجه سيسكو == Computer Based Configuration For Cisco Routers

Author name: فارتان رافي كريكوريان
Supervisor name: غسان حميد عبد المجيد
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electronic And Communications Engineering
Language: English
University location: Baghdad
First pages:
Abstract: Routers are intelligent devices that make connection between different networks possible. In addition, routers can perform several functions, including filtration and selection of the best path of packets movement. Routers must be configured efficiently in order to perform the above functions. In literature, two approaches have been distinguished for the configuration, namely; text mode and graphical mode approach. The present work is analyzing these two approaches and defines precisely their advantages and limitations. As a result of this analysis, a new approach is proposed in this thesis which eliminates the limitations. The work proposes a graphical interface which is executed on a desktop (or laptop) PC. The user defines the configuration parameters through a program which transfers these parameters to the router by console port instead of Ethernet port. These parameters are then saved on Non Volatile Random Access Memory. The proposed graphical interface is implemented by standard lab consisted of two routers. The implementation shows that the time of configuration can be reduced to 70% of the text mode approach, and overcome the trouble of the old graphical interface.