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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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electrical Engineering
Language: English
Full text from the source: https://nahrainuniv.edu.iq/sites/default/files/Thesis_57.pdf
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
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Al-Nahrain University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

الهوائي الشريطي الدقيق واسع النطاق الترددي لتطبيقات الجيل الثاني والجيل الثالث لمحطه قاعده الهاتف المحمول == Broad Bandwidth Microstrip Antenna For 2G, 3G Mobile Base Station

Author name: وفاء محمد هاشم
Supervisor name: عضيد حسن سلومي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

تصميم وتحليل مصفوفات هوائيات مطبوعة احادية القطب == Design and Analysis of Printed Monopole Antenna Array

Author name: نور باقر حسن
Supervisor name: رعد حمدان ظاهر
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

التعرف على الشخص اعتمادا على القزحيه الملونه البيومتريه والتحويلات الكونتورية == Person Identification Based on Colored Iris Biometric and Contourlet Transform

Author name: ضحى حسين حميد
Supervisor name: ماهر خضير محمود
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

تحسين اداء منظومات الطيف المنتشر المتعدد الوصول بالقفز الترددي باستخدام المتتاليات الفوضوية == Enhancing the Performance of Frequency Hopping Multiple Access Spread Spectrum System Using Chaotic Sequences

Author name: سهاد قاسم نعيم
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

تصميم وتحليل هوائي متغير الرقعة لتطبيقات Wi - Fi وWiMAX == Design and Analysis of Microstrip Patch Antenna for Wi-Fi and WiMAX Applications

Author name: زينب سعدون جميل
Supervisor name: رعد حمدان ظاهر
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

تاثير توزيع مستخدمي النقال في سعة انظمة الاتصالات الوصول المتعدد بتقسيم الزمن وتقسيم الترميز == Mobile Distribution Effect on TDMA and CDMA Capacity

Author name: دلال كنعان طاهر
Supervisor name: عضيد حسن سلومي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

تصميم هوائي شريطي دقيق ذو نطاق فائق الحزمة الترددية (UWB) ذو خصائص قطع الحزمة == Design of UWB Microstrip Antenna with Band Reject Characteristics

Author name: براء علي كريم
Supervisor name: عضيد حسن سلومي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

بوابات CNOT حتمية مقترحة مبنية على التحويل الفوتوني المتشاكه == Proposed Deterministic CNOT Gates Based on Coherent Photon Conversion

Author name: جواد عبد الكاظم حسن
Supervisor name: Khalil Hajim
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad
Language: English
University location: Baghdad
First pages:

تقليل استهلاك القدرة في تصميم دوائر السيموس المتكاملة بالاعتماد على الخوارزمية الجينية == POWER MINIMIZATION IN CMOS INTEGRATED CIRCUITS DESIGN BASED ON GENETIC ALGORITHM

Author name: علي طويج شاهين
Supervisor name: سليم محمد رضا طه
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Doctorate
University: University of Baghdad
Language: English
University location: Baghdad
First pages:

حساب توزيع الطاقة الممتصة في راس الانسان باستخدام نطاق الفرق الزمني المحدد لانظمة الاتصالات المتنقلة == Computation Of Sar Distribution In Human Head For Cellurlar Mobile Communication Systems Using Fdtd

Author name: هويدا كمال عبد الفتاح
Supervisor name: عضيد حسن سلومي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: Widespread wireless communications system in the last few years, leads people to ask many questions about the advantages and disadvantages of those systems, especially about electromagnetic waves pollution and their effect on human health.The mobile device is frequently used by the general public from adult to child, one of the main sources of electromagnetic waves and very close to the human head. Therefore the focus of this research on the impact of electromagnetic waves from mobile to human health by measuring the Specific Absorption Rate (SAR), at the human head and the hand through SEMCAD - X that uses the Finite Different Time Domain (FDTD). SAR computation uses (FDTD) in the way the limited space of time, to calculate the specific absorption rate. The results have been compared with standards averaged over any 1 g of tissue and averaged over any 10 g of tissue. It didn't exceed the applicable standard.This work evaluates specific absorption rate (SAR) at different ages of three people. Firstly, old man, who was estimated to head 100% size of header used in the program SEMCAD - X. Secondly Adult man was estimated his head by 85% size of header used in program, and finally the child who was estimated his head by 65% size of header used in the program SEMCAD - X, the design hand has been used with all cases.The design of the mobile phone software works in four different packages of frequencies; the packets are the center frequencies 900MHz 1800MHz, 2100MHz and 2400MHz, when increased frequency the SAR increased but in the some state and frequency decreasing.The Evaluation of SAR in the head and the hand of the user device and the generic phone, the highest value of SAR decreases with increasing distance between the generic phone and the user's head and reducing the proportion was 50% for the old man, 40% for adult man and 35% for child. It can be noted that the angle of the rotation of the various frequencies is not fixed, while the ratio approximately is 25% for each angle of rotation.Also, it can be noted that for fixed frequency, the input power is increased to a double and the SAR have been used increased almost to a double.The different positions show that the methods of holding generic phone have a significant impact on the value of SAR. Therefore, the value of SAR can be reduced into 90% when using the correct method.The evaluation of SAR in these cases shows their influence on children and it was much greater than the adult human or old human by parentage 40% old man and 35% adult man.

التاثيرات الكهربائية والبصرية لتشويب اغشية اوكسيد الخارصين (ZnO) المكونة لمتحسس الاشعة فوق البنفسجية بالفضة == Electrical And Optical Effects Of Ag Doped ZnO Thin Film Based MSM UV Photodetectors

Author name: محمد وسام ناجي
Supervisor name: منير عبود هاشم | غصون محسن علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: يستخدم اوكسيد الخارصين (ZnO) لكشف الاشعة فوق البنفسجية وذلك لكبر فجوة الطاقة وكبر طاقة اثارة الربط لهذا الشبه موصل. اوكسيد الخارصين كذلك يمتلك سرعة اشباع عالية وفولتية انهيار عالية. في هذا العمل تم تصنيع متحسس اشعة فوق بنفسجية نوع (معدن - شبه موصل - معدن) با | Zinc Oxide (ZnO) has been commonly used for ultraviolet detection due to large band gap and excition binding energy. ZnO has high breakdown electrical field, also has a much larger saturation velocity. In this work three ultraviolet Metal Semiconductor Metal (MSM) photodetectors were fabricated, based on ZnO and Silver (Ag) doped Zinc Oxide (SZO) with (2% and 4 % doping ratios) thin films. The technique used to prepare the thin films was sol - gel and spin coating technique by using Si (100) p - type. Silver interdigitated (IDT) electrodes were deposited on the films by a vacuum coating deposition technique to form the three devices.The electrical properties for the fabricated photodetectors (PDs) were studied using Semiconductor Characterization System (SCS) at room temperature ( 27 C^o). The applied voltage was in the range of ( - 5 to 5) V.The SEM images showed a non - uniform distribution of the Ag dopants, these dopants formed clusters and these clusters increased as the amount of Ag dopants increased. The mobility, carrier concentration, and roughness for the SZO films increased when compared to undoped film. The optical bandgap and the transmittance are decreased when the doping ratio is increased. The saturation current (I - S) was decreased by a factor of 4, and 12 for the devices based on Ag doped ZnO (with 2% and 4 % doping ratios) thin films, respectively. The sensitivity was significantly increased with increasing the doping ratio. This enhancement attributed to the roughness of the Ag dopants (clusters). The detectivity was increased for the devices based on SZO films. The high detectivity with low saturation current made the devices based on SZO films suitable for optoelectronic applications and integrated circuits. From the experimental data and analysis, it was found that the PD with ZnO : Ag 4 % doping ratio has higher responsivity and gain of 0.523 A/W and 257 , respectively. This is confirmed by thin film and device characterization which makes this PD suitable for UV detection purposes.

النمذجة التحليلة لاداء الثنائي الضوئي p - i - n == Analytical Modeling Of A P - I - N Photodiode Performance

Author name: محمد شهاب احمد
Supervisor name: منیر عبود ھاشم
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The analysis of a silicon p - i - n photodiode with a uniform doping concentration in each layer is presented. The theoretical treatment aims at investigating the device operation and performance to obtain optimum values of photodiode parameters when operates as a photodetector.Large bandwidth, good responsivity, device speed and quantum efficiency at wavelength of interest, combined with its low operating voltage and capability, make this diode promising for optoelectronic receiver circuits for use in optical communication systems and computer interconnections.High speed silicon p - i - n photodiode which operate at 700 nm wavelength is reported. By using a reverse bias voltage to control electric field, a high quantum efficiency of 80% is attained corresponding to bandwidth of 6.5 GHz at depletion width of 5.36 ?m and biasing voltage of 27.5 V. The minimum detectable incident light signal power is 3.9 ?W corresponding to signal to noise ratio of 6.5*104. The results show that, there is trade - off between quantum efficiency and bandwidth. Since the intrinsic layer of a p - i - n photodiode can be made with a lightly doping concentration, a p - ? - n photodiode is also treated mathematically with a software tool, and the results obtained are very close to those for a p - i - n photodiode. The results are achieved with the aid of MATLAB programming tool version 8.1.0.604 (R2013a).

تصميم وتنفيذ معالج باستخدام TM - CFAR مصفوفة البوابات المبرمجة FPGA == Design And Implementation Of TM - CFAR Processor Using Field Programmable Gate Array

Author name: علي هادي عبد الواحد
Supervisor name: وليد خالد عبد علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: This Thesis proposes on a project whose aim is to implement architectures for CFAR processor employed in radars. These proposed architectures are implemented by using Field Programmable Gate Array (FPGA) technique, with observance of feature desired as flexibility and speed without performance loss. This design written in VHDL Hardware Description Language that can be used to accelerate the implementation. In this thesis, the proposed by design is implemented using MATLAB Simulink on the Trimmed - mean Constant False Alarm Rate Processor(TM CFAR) to obtain system parameters and to test the flow of signal through the system, and then used FPGA devices. FPGA architecture of TM - CFAR processor is implemented to overcome the large processing time required in case of multi - target environment. The use of this technology is suitable because it offers high flexibility in modifying and even developing the required design with a reduction in the required number of hardware and cost. In addition to the main features of the processing chain architectures such as degree of parallelism, small size, accuracy and high computational speed, there is a requirement for generality and adaptively i.e. the ability to handle many different models of operation in different environments. The FPGA implementation of the design is achieved using Xilinx Virtex - II platform as a suitable selected programmable device. The development of the system software for this work has been done using Active HDL 3.5, and ISE Navigator 6.3i programs.

تمييز الاهداف الرادارية وذلك عن طريق استخدام الشبكات العصبية وافضلية الحشد الجزيئي == Radar Target Recognition Using Neural Network And Particle Swarm Optimization

Author name: علي ناظم غالب
Supervisor name: وليد خالد عبد علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: In the last decades, the pattern recognition and classification are taking an important area of the research. One of the main applications of pattern recognition is the radar target recognition which is vital in radar system.In this this work, a radar signal were used and analyzed for three targets present a contribution is this trend (aircrafts SR - 71, C - 130 and AH - 64), and used as initial data, then variations are made to simulate the target signal variation (50 range profile for each target).A wavelet transform (multi resolution decomposition) is used to reduce the dimensions of radar range profile and then leads to reduce storage and computation.The wavelet transform including two procedures, the first one using approximation and details coefficients as feature extraction, while second procedure use related with the details coefficient only.Artificial Neural Network (ANN) is used as recognizer. The Feed Forward Neural Network (FFNN) and Elman Recurrent Neural Network (ERNN) are used. The network was trained using Supervised Learning Algorithms. The FFNN was trained by (Levenberg - Marquardt (lm), Bayesian regulation (br), particle swarm optimization). The (ERNN) was trained by (lm, br).The best recognition rate of three targets is obtained by using the feature extraction from (normalized details wavelet coefficient) and the ERNN trained by (br). The recognition rate in this procedure is about 96% compare with other methods.When adding the AWGN S/N=5db, the recognition rate reducing to 85%.

تمييز الوجوه اعتمادا على التحويلات الكونتورية ومصنف الشبكة العصبية متعددة الطبقات == Face Identification Based On Contourlet Transform And Multi - Layer Neural Network Classifier

Author name: علي فتاح حسون
Supervisor name: ماهر خضير محمود
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: Face recognition plays an important role in many applications like security, banking, access to buildings, and surveillance …. etc.Because of the face image can significantly change due to changing in some factors, such as lighting conditions, facial expression, and others factors, therefore face recognition is still a challenging mission. Useful properties of the Contourlet Transform (CT) are exploited in this thesis to investigate more discriminant features to enhance the face identification performance. In this thesis, a face identification system is suggested based on CT, and Multi - Layer Neural Network (MLNN) Classifier. The main reasons behind using the CT are : First, the CT supports progressive data compression/expansion, hence it is used for image compression. Second, the features in human face are not just horizontal or vertical. CT is utilized for feature extraction because it is a genuine 2D transform that can capture the edge information in all directions. After decomposing an image by CT, low and high frequency coefficients of CT are calculated in different scales and various angles. Most significant information of faces is contained in coefficients, which is important for face identification. The frequency coefficients are utilized as an input feature vector for a neural network classifier. Simple feed forward MLNN neural network is used to achieve the identification process. The network parameters are tuned to optimal values, in order to produce fair comparison between different types of feature vectors. To evaluate the algorithm performance, seven standard databases, and a proposed database are used. Some of them are of high variability, to examine the algorithm robustness against variability. In addition, the proposed algorithm is also evaluated using a generated database composed from five databases. Then the suggested method is compared with other classical feature - based methods such as, wavelet, Principle Component Analysis (PCA), and CT - PCA. The results indicate that the CT - based method has better identification (ID) rate, and is faster than the Wavelet - based and the PCA - based methods. This is due to the high sparsity of the CT and its efficient capability of compression. The ID rates obtained for a tested databases are Japanese Female Facial Expression (JAFFE) database (100%), face 94 database (99.34%), proposed database (98.55%), ORL database (96.5%), Senthil database (92%), Yale database (90%), FERET database (76.2 %), and FEI database (72.57 %), and comparing with other systems, an average identification rate 90.64% for the CT, 85.71% for the Wavelet, 53.92% for the CT - PCA, and 46.7% for the PCA for all tested databases.Moreover, the characteristics of low and high frequency sub bands a are studied with their effect on ID rates. The simulation results indicate that the best identification rates are obtained when using only the low frequency sub - band for all tested databases

استخدام اغشية اوكسيد الخارصين (ZnO) الرقيقة في متحسس لتركيز الهيدروجين من نوع ترانزستور تاثير المجال ممدود البوابة == Zinc Oxide Thin Films - Based Extended - Gate Field - Effect Transistor (EGFET) As Ph Sensor

Author name: علي عزام عبد اللطيف
Supervisor name: رعد حمدان ظاهر | غصون محسن علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: ظهر في السنوات الاخيرة اهتمام ملحوظ في استخدام متحسسات تركيز الهيدروجين (الرقم الهيدروجيني) من نوع ترانزستور تاثير المجال (FET) في التطبيقات الطبية الحيوية مثل دم الانسان, اليوريا واللعاب لان عملية تصنيع متحسسات تركيز الهيدروجين تتجه نحو التكلفة المنخفضة | In recent years, there is noteworthy interest in using pH - sensors based on Field Effect Transistor (FET) in biomedical applications such as human blood, urine, and saliva because the fabrication of pH - sensors is tending toward low cost, small size, disposable, and real - time measurement. In this work, Extended Gate Field - Effect Transistor (EGFET) pHsensors were built using thin films of Zinc Oxide (ZnO) doped with Palladium (Pd) as sensing membranes. The Pd - doped ZnO thin films with different molar concentrations (Pd = 0%, 2% and 4%) were deposited onto p - type Si(111) substrate by sol - gel method. The surface morphology of the prepared films was imaged and studied by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). The crystal structure of the fabricated films was examined by X - Ray Diffraction (XRD) test. The optical and electrical characteristics of the films were measured using spectrophotometer and Hall - Effect measurement device, respectively.The EGFET pH - sensor has been prepared by linking the fabricated sensing devices to the gate terminal of a commercial Metal - Oxide - Semiconductor Field - Effect Transistor (MOSFET CD4007UB).The fabricated sensing devices were immersed in buffer solutions with pH range of (pH 3 ? pH 11). The pH sensing characteristics of ZnO and Pd - ZnO/silicon EGFET devices were studied using Semiconductor Characterization System (SCS - Keithley 4200).The ZnO EGFET sensor exhibits voltage sensitivity and linearity of 31.5 mV/pH and 0.9809 (or 98.1%) in linear regime with pH range of (pH 3 - pH 11). The voltage sensitivity and linearity of Pd - doped ZnO (with 4% molar concentration of Pd) EGFET device in the linear regime with pH range of (pH 5 - pH 11) are 27.86 mV/pH and 0.9785 (or 97.85%), respectively. The experimental results show that the Pd - doped sensing films by sol - gel method cannot be adopted for whole pH range. This means that the doped films have fewer amounts of H+ ions sensing sites at its surface than undoped ZnO fims.

تصميم وتحليل هوائيات مغيرة الرقعة للتطبيقات ذات الحزمة العريضة == Design And Analysis Of Slotted Patch Antenna For Wideband Applications

Author name: سيف ناظم غالب الساعدي
Supervisor name: رعد حمدان ظاهر
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The main objective of this work is to design, fabricate and test irregular, diamond wideband microstrip patch antenna which satisfy UWB. A series of parametric study is conducted to show how the characteristics of the antenna depend on the various geometrical and other parameters. These geometrical parameters of the antenna include the dimensions of the patch, feeder and ground plane. Slots are inserted different shapes and sizes in antennas to show which give different bandwidth. The first designed antenna has regular pentagonal patch and 50? microstrip line on one side of dielectric substrate and partial ground plane with square slot on other side. This antenna gives dual bandwidth 2.73 - 7.5 GHz and 8.7 - 20 GHz. This antenna is modified by changing the patch from regular to irregular pentagonal patch with the same area and fixe the other parameter of the antenna. Therefore, the antenna is improved in term of bandwidth and gain, which gives bandwidth of 2.74 - 20 GHz. Many slots with the different shape and size are added to the irregular pentagonal patch to modify this antenna, which makes this antenna have bandwidth of 2.6 - 20 GHz which is suitable for the application that operating in this band. The second design consists of diamond patch and microstrip feed line on one side of dielectric substrate and partial ground plane has square slot on the other side. This antenna is modified by adding three slots in the patch which modifies the gain, so this gives bandwidth of 2.3 - 18.5 GHz. The third design consists of irregular pentagonal patch that is fed by 50? Coplanar Waveguide (CPW) and 4 - step stair added to ground plane is printed on one side of dielectric substrate and c - shape independent piece on other side. This antenna gives bandwidth of 1.48 - 14.2 GHz which is suitable for the applications that operating in this bandwidth. The fourth antenna consist of diamond patch that fed by 50? Coplanar Waveguide (CPW) and 4 - step stair added to ground plane is printed on one side of dielectric substrate and independent piece on other side. This antenna is suitable for the applications which is operate in band of 1.35 - 16 GHz. The design and simulation of the antenna is carried out using CST microwave Studio simulation software.

محول خفض الفولتية المستمرة باستخدام المكثف المفتاحي == Switched - Capacitor Based Step - Down DC - DC Converter

Author name: سؤدد زاحم حسين
Supervisor name: تركي كحيوش حسن
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: المحـــــــــــول الخافـــــــــض للــــــــــــفولتيـــــــــة المستمرة ذو المكثف المفـــــــتاحــــــــي (Switched Capacitor DC - DC Converter ) يمكن ان يستعمل للتحويل الكفوء للطاقة حيث نجد انه عندما لا تستعمل المحاثات في دوائر التحويل يؤدي الى خفض حجم | Switched - capacitor (SC) - based step - down DC - DC converter can be used for efficient power conversion when inductors are not used in order to reduce size and cost. In addition, switched - capacitor DC - DC converters are superior to inductor - based converters for high - conversion ratio and wide range of load variation. In this thesis , a multistage current - controlled switched - capacitor step - down DC - DC converter is analyzed , designed and simulated. The converter features are of good regulation capability and continuous input current waveform when two step - down converter cells are connected in parallel and operate in antiphase. Classical SC converter with pulse width modulation technique is also analyzed, designed , simulated. For the PWM converter and current - controlled converter , third - order state - space averaging technique is used for analysis. A fuzzy logic controller is used with the current - controlled converter to obtain fast dynamic response, low ripple in the output voltage and robustness against load and supply variations. A 70W ,48/12V and 12.5W 48/5V converters are designed and simulated ( Matlab/Simulink is used for simulation). The simulation results are obtained and compared for the above converters with different control techniques (PWM ,current control with PI controller and current control with fuzzy controller). The results for current - controlled converters with fuzzy controller show higher efficiency , lower ripples in the output voltage ,fast transient response, good disturbance rejection and very small steady state error of output voltage. In this thesis the value of the output ripple must less than 0.05 V and the efficiency should be more than 75 % for current control mode

ترميز القناة المرتكز على الاشارات الفوضوية == Chaos Based Channel Coding

Author name: سراب كمال محمود
Supervisor name: حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

الرؤية المجسمة لتخمين المسافة باستخدام SAD مع مرشح كشف الحواف Canny وتقنيات التعويض == Stereo Vision Distance Estimation Using SAD And Canny Edge Detector With Interpolation Methods

Author name: زيد خضر حسين
Supervisor name: رعد حمدان ظاهر
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: Stereo vision system is a technique for finding depth data for digital images.The stereo vision system is used to obtain a 3D data from 2D scene taken by two optical cameras (left and right cameras); the taken images can be used to find the distance of the objects. A number of algorithms for stereo vision system have been developed and the matching algorithms. This work focuses on the traditional algorithms used the Normalized Cross Correlation (NCC), Sum of Absolute Differences (SAD) and the modified version of SAD algorithm. This method is called the Canny Block Matching Algorithm (CBMA) which can find the disparity map. The proposed algorithm contains two parts; the Canny edge detector and Block matching technique with SAD to determine the disparity map and reduce the execution time, the execution time of the CBMA is between (0.35 - 0.43secs) and neglected the effect of the windows size results in the CBMA algorithm. The interpolation method is used which consists of median filter and interpolation techniques (i.e., the most common techniques : bilinear, 1st order and 2nd order polynomial) to enhance the output results images.The error percentage has been reduced about 2% for the disparity map of the CBMA algorithm after used the bilinear interpolation method with block size [3x3] and the execution time is reduced by the step size windows. MATLAB program has been adopted to write the proposed algorithms codes. While, the interpolation techniques has been implemented using in Microsoft Visual Basic (6.0). The camera calibration and image rectification is used to find camera parameters and to simplify the correspondences search. The system was implemented using two identical cameras with baseline (16cm) to detect the distance objects.

تصميم شبكة استشعار لاسلكية متينة لمراقبة استهلاك الطاقة == Robust Wireless Sensor Network For Energy Monitoring

Author name: حيدر عبد الحميد محمد جواد العبيدي
Supervisor name: حكمت نجم عبد الله | طارق محمد سلمان
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: There has been a quick development in the Wireless Sensor Network (WSN) field that promises to revolutionize the way people lives. Where they have a wide range of applications especially in the monitoring applications like power consumption, military, and healthcare. This thesis has three objectives. First, to design and implement a prototype of WSN for monitoring power (as well as temperature) in buildings. Second, to investigate the bounds of coverage in different building construction materials. Third, to evaluate the amount of improvement introduced to the ZigBee transceiver when channel - coding methods are used.The basic design elements of the implemented power and temperature monitoring system includes current sensors, temperature sensors, microcontrollers, and wireless transceivers implemented using Global System for Mobile Communications/General Packet Radio Service (GSM/GPRS) platform and ZigBee technology. The use of GSM/GPRS platform allows the user to control or gather information about the system from anywhere just by sending a request using Short Message Service (SMS). In addition, the measured data can be visualized through a user friendly Graphical User Interface (GUI). Many measurements have been done to find the exact limitation of the designed system in terms of coverage and signal strength in the presence of objects of different materials including; cardboard, metal, concrete bricks, wood and corkboard. Furthermore, the MATLAB Simulink model of the proposed ZigBee transceiver uses Convolutional Coding (CC) at different code rates to improve the performance in AWGN channel, Rayleigh and Rician multipath fading channels.The results indicated that the use of ZigBee based WSN in electric power monitoring provides flexibility and helps in reducing power consumption. In addition, the experimental results show that the construction materials of buildings have varying impact on the network performance. At 4m distancebetween the base station and the sensing node, the losses in signal strength are 15, 20, 21 and 32 dBm when using metal as compared with cardboard, corkboard, wood and concrete bricks respectively.It is observed from the simulation results that using convolutional coding in ZigBee transceiver gives better performance than the traditional ZigBee transceivers and that the convolutional code of code rate 1/8 gives the best performance compared to other CC. In AWGN channel and at BER of 10 - 4, the maximum performance improvements in terms of BER obtained over traditional system are 14dB and 13.5dB for OQPSK and BPSK (868 - 900MHz) based ZigBee respectively. While these improvements are 23.5dB, 40.5dB and 19.5dB, 12.5dB in Rayleigh & Rician channels at the same BER respectively.

تقييم اداء نظام الاتصالات المتعدد المستخدمين المرتكز على متجهات فوضوية متعامدة == Performance Evaluation Of Multiuser Communication System Based On Orthogonal Chaotic Vectors

Author name: بسمة نزار ناظم
Supervisor name: ماهر خضير محمود
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: In DS - CDMA systems, the use of orthogonal spreading codes with low cross - correlation values is needed to suppress the effect of multiple access interference (MAI) which increases as the number of active users in system is increased.Currently, the conventional PN sequences, such as (Gold codes, Kasami codes …etc.), generated by linear feedback shift registers (LFSRs) and orthogonal variable spreading factor (OVSF) were used as spreading codes in DS - CDMA system. Using these sequences, it is not possible to increase the number of active users in the system due to the fact that the possible sequences generated in conventional PN - system are limited in number and offer mutual interference as the number of active users is increased due to its non - zero cross - correlation values. The chaotic system can be used to generate very large number of quasi - orthogonal sequences compared with the number of PN sequences due to its sensitivity to initial conditions. Another type of chaotic sequences with zero values of cross - correlation called Orthogonal Chaotic Vectors (OCVs) is generated using chaotic systems and the basic idea of Gram - Schmidt ortho - normalization process.In this work, the use of OCVs in synchronous DS - CDMA system for transmission of data over (AWGN, Flat fading and Frequency selective channels) is introduced. The simulation results show that the DS - CDMA based on OCVs gives better BER performance when spread factor ? is greater than the number of active users due to the reduction of MAI between active users.Results show also that, at BER = - in AWGN channel and for 5 users, there are gain of (0.3, 1.2, 1.75 and 3.75) dB between system based on OCVs and systems based on small set Kasami sequence, Gold codes, large set of Kasami sequence and Non - OCVs respectively. Under the effect of flat fading channel, it can be noted that at BER = - and for 30 user, there is 1.7 dB gain between system based on OCVs and system based on small set of Kasami sequences, and this gain increases to 2 dB for 50 user.Under time invariant frequency selective fading channel and for 8 users at BER= - there is about 6dB gain between the system based on OCVs and system based on Non - OCVs.

الدالة الغامضة للاشارة الرادارية المرمزة == Ambiguity Function Of Radar Coded Signals

Author name: اياد عطيه عبد الكافي الجبوري
Supervisor name: نزار خليل وفي | وليد خالد
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electronics and Communications Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: تم دراسة انواع متعددة من تر ميزات الاشارة الرادارية حيث تم التركيز في هذه الدراسة على خواص الارتباط والغموض للتر ميزات. كذلك تم التركيز على تاثير دوبلر على تلك الخواص. تم دراسة تاثير الخطا الطوري والتعيير(Weighting) على خواص تلك الترميزات. الدراسة ال | Various types of coded radar signal are studied in this study in terms of their ambiguity and correlation properties. Doppler effect on the ambiguity and the correlation functions of these codes is studied. The effect of phase error and weighting are presented.The study related to Doppler effect covers the frequency, binary and polyphase codes in terms of the peak signal to sidelobes ratio (PSR).Linear FM, nonlinear FM, binary and polyphase codes with various windows, are dealt with respect to the sidelobes response. The simulator built using Matlab version 6. The simulation consists of a code generator; modulator; white noise adder; received signal with time and frequency shifted; matching filtering; a module to find the Doppler effect on the autocorrealtion function and a module to find the peak signal to sidelobes ratio (PSR). It is found that the m - sequences are the best binary codes in terms of PSR and the P4 code is the best Polyphase code in terms of PSR. Also, it is found that the P4 code provides better Doppler tolerant than the other codes. The m - sequences are very sensitive to Doppler shifts. Concerning the frequency codes : it is found that the nonlinear FM is more sensitive than the linear FM i.e., linear FM is Doppler tolerant while the nonlinear is not. Finally, it is found that the use of time weighting produces a response with extremely low sidelobes
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