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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:

خوارزمية فعالة للسيطرة على التردد اثناء تغيير الحمل في منظومة القدرة == An Effective Algorithm Of Load Frequency Control In Power System

Author name: ساره عباس حسين
Supervisor name: قاسم عبد الرزاق الانباري | عباس حسين مري
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: في السنوات السابقة، زادت اهمية تحسين النظام الكهربائي. وان ثبوت التردد هو واحدة من الاشياء التي اثرت في خصائص النظام الكهربائي هي ثبوتية التردد. ولهذه الغاية، وحدة التوليد ملحقة بمسيطر اوتوماتيكي على التردد اثناء تغيير الحمل (LFC) لتنظيم القدرة الفعالة | In recent years, the importance of improving electrical power has been increased. One of the things influenced the characteristic of electrical power is the constancy of frequency. To this end, the generator unit is equipped with an automatic load frequency control (LFC) to adjust the active power produced and restore the frequency and tie line power exchange to their nominal value.The total model of a hybrid power system has a high dimension. The classical design tools are inadequate to cope with all dynamic features. Artificial intelligence techniques are found to be a promising tool to optimally minimize the transient dynamics and control efforts in a load frequency control. This thesis shows the execution of various Artificial Intelligence techniques on the tuning of PID controller in a load frequency control system to compute the PID controller. The techniques of genetic algorithm technique GA, particle swarm optimization PSO and artificial bee colony ABC were applied on four areas, six tie lines power system. The dynamic model was formulated in state variables form. A comparison between these techniques with different performance indices was presented. Results of the test system 1 and 2 were computed and compared. They showed that in test system 2 the load frequency controller can chase the load fluctuation in a short time. The IAE performance index gives an optimum dynamic performance using ABC. From the outcomes, they show that the test system 2 outputs regarding settling time and maximum overshoot were the best performances.

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.

تصميم وبناء شاحنة بطاريات ذكية لمنظومة القدرة التي تعمل بالالواح الفوتوفولطائية == Design And Implementation Of An Intelligent Battery Charger For A Photovoltaic Power System

Author name: حسين سعود مرض
Supervisor name: عصام محمود عبد الباقي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering - Power and Machinery
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: ان الهدف الرئيسي من هذه الرسالة هو استخدام الطاقة الشمسية لشحن بطاريات الرصاص الحمضية. تعتبر الشاحنة من اهم اجزاء المنظومة الشمسية وذلك لكون بطاريات الخزن هي الجزء الوحيد المحدود العمر منها. بطاريات التخزين ضرورية في جميع المنظومات الكهربائية الشمسية المس | The main goal of this thesis is to use the photovoltaic (PV) power to charge Lead - acid batteries. The charger is the most important part of the solar system because the only limited - age part of this system is the storage batteries. Storage batteries are essential in all standalone PV power systems. Their efficiency and life time affects significantly the overall PV system performance and economics. The storage battery's effectiveness depends on the charging process. Hence, this thesis deals with the study, simulation and design of an intelligent charger fed by solar system due to the latest technologies.The developed charging method entitled "the decreased charging current based on state of charge" is adopted in this thesis to charge a lead - acid battery. The principle of decreased charging current is to make the real charging current as close as possible to the maximum acceptable current. The advantage of this technique is to mix between the rapidity of charging and prevents of the overcharging and generates gases.The maximum power point tracking (MPPT) technique is adopted to maximize the PV output power, whatever of the temperature and irradiation conditions. The design considers different operating conditions of load, battery state of charge (SOC) and ambient effect in order to achieve the best charging condition of the batteries and to be compatible with the user requirements. The flexible, simple and cheap design is the objective of this charger.This PV charging system is composed of a solar panel, lead - acid batteries, buck converter as power charging circuit and a microcontroller as a control unit.The simulation results are achieved by using Simulink Proteus Isis Professional software. These results demonstrated the validity of the proposed charging technique. The battery charger prototype was tested and the obtained results agree with those obtained from the simulation

اداء التجميع المتعامد لاشارات تقسيم الشفرات المتعدد الوصول ذات الحاملات المتعددة (Rayleigh) عبر قناة الخفوت الترددية الاختيارية من نوع == Performance Of Group Orthogonal Multicarrier Code Division Multiple Access Signal Over Frequency Selective Rayleigh Fading Channel

Author name: حارث اكرم ناصر العبيدي
Supervisor name: مها جورج زيا
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: مع ظهور قنوات الخفوت الترددية الاختيارية المتعددة المسارات. اصبح نظام تقسيم الشفرات المتعدد الوصول (CDMA) يعاني من التداخل بسبب تعدد المستخدمين (MUI) والتداخل بين الرموز(ISI) ولكن مع التصميم المناسب لنظام تقسيم الشفرات فانه يوفر التفريق الى مسارات متعدد | In the presence of frequency selective multipath fading channels, code division multiple access (CDMA) suffers from multiuser interference (MUI), and intersymbol interference (ISI), but when properly designed, it enjoys multipath diversity. Orthogonal frequency division multiple access (OFDMA) is MUI free, and it does not enable the available channel diversity without employing error control coding. But coded OFDMA may achieve lower diversity than a CDMA system employing the same error control codes. In this work, the advantages of OFDMA and CDMA are merged to minimize MUI effects, and also to make the maximum available diversity for every user possible, this system is called group orthogonal multicarrier CDMA (GO - MC - CDMA).In group orthogonal multicarrier CDMA (GO - MC - CDMA) scheme, groups of users share a set of subcarriers. By carefully choosing group subcarriers, there is aguarantees that every user transmits with maximum diversity. MUI is only present among users of the same group, and is suppressed via multiuser detection, which becomes practically feasible by assigning a small number of users per group. The performance of GO - MC - CDMA system is analyzed with 3M bits/sec in two paths frequency selective Rayleigh fading channel. Moreover, simulations are carried out to illustrate the performance of GO - MC - CDMA with number of active users, number of subcarriers, space diversity combining technique, types of spreading code, type of data detection techniques, finally, the effect of near - far problem.

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.

تعديل التشويه في الصور الرقمية باستخدام خارطة التشويه والمرشحات الضبابية == Correction Of Deformed Digital Images Based On Deformation Map And Fuzzy Filters

Author name: ايهاب ابراهيم كاظم
Supervisor name: ظافر رافع زغير | محمد علي توفيق
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: During the last decades the development in digital image acquisition, capturing, processing and displaying devices is one of the fastest growing fields. Most of these devices introduce some amount of geometric lens deformation and cause uncorrected dimensions in displaying the objects, such as cameras, scanners, lenses, and mirrors.This work introduces a general algorithm use to correct the images deformed by a fixed and known properties sources. A simple prototype system consists of convex mirror and digital camera has been constructed to capture the required reflected scene. The proposed algorithm considers three main processes; correction, filtering, and edge enhancement. The idea of the proposed correction method is based on selecting an original image, capturing its reflected view from the convex mirror, and then obtaining the deformed ratios for each row and column between the captured image and the original image. These ratios represent the raw components to what referred here as the deformation - map. This map is considered as a general pattern for the proposed prototype system, to be used later in correcting the deformed images.The correction process depends mainly on stretching - padding - cropping. In the first operation, each row and column is stretched to a length depends on the corresponding compression ratio's element in the deformation - map. The second operation modifies the size of the image by adding pad array to the end sides, while the third operation crops the image to the required size.The Filtering, and edge enhancement processes are based on using fuzzy median filter to deblur and smooth the corrected images, while fuzzy edge detection is used to enhance the edges of corrected images.The deformation - map has been examined on correcting several deformed images. The results show high capability of considering this map as a general correction model for the images captured by the proposed system.

موثوقية نقل بيانات بمعدل عالي باستخدام متعدد المداخل والمخارج لقناة متعددة المسارات == Reliability Of High Data Rate Using MIMO For Multipath Channel

Author name: ايمان احمد فرحان
Supervisor name: رعد حمدان ظاهر | محمود فرحان مصلح
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: The most important type of MIMO is the Spatial Multiplexing (SM) which is used to increase the data rate depending on the number of transmitted and received antennas. The main challenge of SM is high Bit Error Rate (BER) at low Signal to Noise Ratio (SNR), which leads to increase the power expended, and this not match the modern requirements of communication system.In this thesis, the performance of MIMO system for Space Time Block Code (STBC) and SM has been investigated. As expected the STBC increase the reliability of data rate while SM increase the data rate with significant BER. Three types of detection have been experimented with SM; Maximum Likelihood (ML), Minimum Mean Square Error (MMSE) and Zero Forcing (ZF). The results show that ML is outperform each MMSE and ZF, but as it is known the complexity of ML increase exponentially with number of antennas and modulation order. ZF is simple one, but it has poor performance.The proposed system is to add channel code serially with SM and maintain the low complexity. The experiments are begun with Convolution Code (CC) to support SM performance. The results show that significant improvement is achieved using this code with ZF detection, it can be getting more than 10 dB of SNR as code gain. But the payment is the redundancy information which can be reduced by using puncturing technique. Also the complexity of Viterbi decoder grows exponentially with large constraint length. The second code is a Low Density Parity Check (LDPC) code which is proposed with suitable parameters to reduce the required iterations in order to achieve real time application for such system. The results confirm that the proposedscheme is outperform the CC by 3 dB of SNR in addition to acceptable complexity and less number of iterations

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

تصميم ومحاكاة نظام اتصالات امن يرتكز على النظام الفوضوي عبر قناة كاوس الضوضائية == Design And Simulation Of Secure Communication System Based On Chaos Over AWGN Channel

Author name: امير كاظم جواد
Supervisor name: حكمت نجم عبد الله | سعد سفاح حسون
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: مع زيادة التطور الكبير الذي يحصل في علم الاتصالات ومع وجود قناة عامة (public channel) تنتقل من خلالها المعلومات زادت المشاكل التي تخص القناة وبالخصوص مشكلتين رئيسيتين هما انتهاك الخصوصية ووجود الضوضاء. بخصوص امنية الاتصال : بما ان القناة عامة وبامكان اي م | With the significant development in communication systems especially with the public channel through which information travels, there are increasing in the channels problems. Among these problems, the two important should be addressed are the information security and the noise. In this thesis, an efficient communication system with high security and high immunity against noise has been proposed. From security perspective, the proposed scheme uses two levels of encryption based on chaotic systems. The first level is chaotic scrambling, while the second level is chaotic masking. Two levels of chaos based encryption make information very secure during their transition in the channel because the key space becomes too large. The simulation results show that the Segmental Spectral Signal to Noise Ratio (SSSNR) of the first level (chaotic scrambling) is reduced by - 5.195 dB in comparison with time domain scrambling. In the second level (chaotic masking), the SSSNR is reduced by - 20.679 dB. It is also show that when the two levels are combined, the overall reduction obtained is - 21.755 dB.Concerning the immunity against noise, the proposed system offers three methods to reduce the effect of noise. The first method is based on sending each scrambled sample more than once. The simulation results showed that gain of this method is 10 dB if we send each voice sample 8 times over the classical method without repetition. The second method relies on the conversion of information from analog to digital format before doing the masking. The simulation results of this method show that the mean square error (MSE) is reduced and this reduction increases as signal to noise ratio (SNR) increase. For instance when SNR=10 dB, the MSE is reduced from ?10?^( - 1) to 2*?10?^( - 2) while it reduced from ?10?^( - 2) to 3*?10?^( - 6) when SNR=22 dB. The third method is increasing the power of the information signal relative to chaotic signal. The simulation results show that when the power is duplicated and at SNR = 24 dB, the MSE is reduced from 3*?10?^( - 3) to 0.5*?10?^( - 4) and to 3*?10?^( - 5) when the signal power is tripled.

تصنيع وتوصيف متحسس اشعة فوق البنفسجية باستخدام اغشية اوكسيد الخارصين الرقيقة == Fabrication And Characterization Of ZnO Thin Film Based Uv Photodetectors

Author name: الاء كريم حسن
Supervisor name: رعد حمدان ظاهر | غصون محسن علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: في السنوات الاخيرة، كان هناك اهتمام متزايد في اشباه موصلات اوكسيد الخارصين للتطبيقات الضوئية ضمن منطقة الاطوال الموجية الفوق البنفسجية وذلك لكون طاقة اثارة الربط كبيرة (60 meV) وطاقة الفجوة الواسعة (3.37 eV) في درجة حرارة الغرفة. في هذا العمل, ثلاث متحسس | In recent years, there has been increasing interest in Zinc Oxide (ZnO) semiconductors for optoelectronic applications in the Ultraviolet (UV) region due to its large exciton binding energy (60 meV) and wide bandgap energy (3.37 eV). In this work, three devices of Metal Semiconductor Metal (MSM) UV photodetectors (PDs) and photoconductors (PCDs) based on ZnO were fabricated in the form of Interdigitated (IDT) MSM structures. The ZnO thin films were prepared by sol - gel spin coating technique, and deposited on a P - type Si and glass substrates. The Nickel (Ni) and Aluminum (Al) contacts were deposited by a vacuum coating deposition technique. The morphological, structural and electrical properties of the ZnO thin films were estimated by using Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X - Ray diffraction (XRD), four - point probe and Hall effect measurements. Optical bandgap of ZnO film was evaluated using a double beam spectrophotometer. With applied voltage in the range ( - 5 to 5 V), the photocurrent, contrast ratio, gain, responsivity, detectivity, and Noise Equivalent Power (NEP) were estimated. The Photodetectors were illuminated with UV of 254 nm at room temperature (27 °C) and under different levels of optical power ranging between (163.2 ?w ? 172.3?w). Current Voltage (I - V) characteristics were studied and the values of the saturation current (I - s), ideality factor (n), barrier height (? - B), reach - through voltage (VRT) and flat - band voltage (VFB) were extracted under dark condition. Data analysis and curves were plotted using origin software (graphing and data analysis). The AFM and SEM images clearly demonstrate the formation of well - aligned ZnO, with smooth nanometer granular structure, dense and a good morphology. The grain size and average roughness (rms) values were found to be (59 nm, 12 nm) on Si substrate and (31 nm, 2 nm) on glass substrate, respectively.For Ni/ZnO/Ni MSM PD on Si substrate, the device has VRT of (0.56 V) and VFB of (1.5 V). The responsivity and detectivity were estimated to be (1.334 A/W and 3×1011cmHz 1/2 W - 1), respectively. I - s was found to be (8.3×10 - 7 A), n (4.4) and ? - B (0.67 eV). However for Al/ZnO/Al MSM PCDs on Si and on glass substrates, the responsivity and detectivity were (0.45 A/W and 1.2×1011 cmHz 1/2W1) and (0.94 A/W and 2.9×1011 cmHz 1/2 W - 1), respectively.The I - V measurement results obtained indicate that, the Ni/ZnO/Ni MSM PD on Si substrate behaves as a typical Schottky contact and the dominant current transport mechanism is field thermionic emission. However semi linear behavior for Al/ZnO/Al PCD on Si substrate and the current flowing through the junction was following thermionic emission mechanism, while a symmetric I - V behaviors and an excellent linear relationship between the current and applied voltage are observed in both direction for Al/ZnO/Al MSM PCD on glass substrate. The estimated responsivities, detectivities with fairly low dark currents make the diodes attractive for practical UV detector applications

تحسين اداء هوائي فيفالدي باستخدام المواد ما بعد المادية == Vivaldi Antenna Performance Enhancement Based On Metamaterials

Author name: ادهم ربيع عزيز
Supervisor name: زيد اسعد عبد الحسين | طه احمد عليوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: يتطرق البحث الى المتطلبات الاساسية في الانظمه اللاسلكيه الحديثة والضوابط المتوافقة مع امكانية اعادة التشكيل وقابلية التحديث مما ادى الى ان يصب مجال الدارسة في تحقيق تصميم هوائي يمكن له استيعاب ذلك. في هذه الدراسة، صمم هوائي مطوي على اساس هيكل فيفالدي مع | The urgent demands for a miniaturized, compatible, reconfigurable, updatable, and additive - able wireless communication systems for advanced handle held and portable electronics devices are rarely relaxed due to the inherent antenna limitations. In this study, developing a folded microstrip antenna based on a novel antipodal Vivaldi structure based metamaterial inclusions of single negative properties is proposed for wideband applications. Although, Vivaldi antennas show unlimited bandwidth, an acceptable directivity, small size, light weight and easy to fabricate, but, it suffers from low gain due to traveling surface waves effects and therefore, it cannot be embedded inside the integrated systems ,where, the radiation direction is in the end - fire that limits their use to the outdoor applications. Therefore, a remarkable attention was the first in the literature, is proposed in this thesis by introducing single negative metamaterials to the folded antipodal Vivaldi antenna structure. This work is developed based on a systematic approach which can be divided mainly into four parts : First of all, design a single negative metamaterial structure of a surface area 5×5 mm2 on an FR4 - Epoxy substrate. The unit cell properties are evaluated numerically and analytically, then, compared to the measurement. Second, a systematic approach is applied to design an antipodal Vivaldi antenna based flat profile of a corrugated shape with 50×38 mm2 on the FR4 - Epoxy substrate. Third, the best arrive of the flat geometry is folded on a hello Teflon substrate of an elliptical cross - sectional area. Fourth, the folded antenna structure is surrounded by a U - shaped single negative metamaterial array. The performance of the all proposed antennas are evaluated numerically, then, compared to their measurements in both S11 and radiation patterns. It is found that the antenna bandwidth has affected insignificantly by applying the metamaterial structures. However, with respect to the flat antenna model, the gain is increased generally by 6 dB as well as the radiation pattern is oriented to the broadside. It is worth to mention that the achieved enhancement in the gain is mostly attributed to the folded substrate and the metamaterial introduction. While, the bandwidth enhancement is mostly obtained from the folded antenna structure. The optimum structure shows a first mode around 1.4 GHz and the second one at 2.86 GHz, while, the flat antenna only one mode at 1.5 GHz is appeared.Finally, the HFSS, CST MWS, Matlab and ADS software packages are used in this thesis to study the unit cell performance and the antenna structure. Excellent agreements have been found between the simulated and measured results.

منظومات تضمين العامل المتغير الفوضوي == Chaos Parameter Modulation Schemes

Author name: ابراهيم فهمي علي
Supervisor name: حكمت نجم عبد الله
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical and Electronic Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: في هذه الدراسة, تم تصميم منظومتين من CPM وتم تقييم ادائهما في مختلف قنوات الاتصال. اولا, تم اقتراح تقنية فعالة لتخمين القيمة الابتدائية للاشارة الفوضوية في منظومة تضمين القيمة الابتدائية المسماة M - ary ICM. هذه التقنية سميت ب MACE. هذه التقنية قللت من تع | In this study, two Chaotic Parameter Modulation(CPM) schemes are designed and their performance in different communication channels has been evaluated. Firstly, an efficient technique for initial condition estimation of chaotic signal in M - ary Initial Condition Modulation (ICM) scheme is proposed. This technique has been called Maximum Auto Correlation Estimation (MACE). It reduces the complexity of the demodulator; thereby, it minimizes the hardware implementation cost. Simulation results confirm that, the proposed technique outperforms the conventional technique used in direct sequence spread spectrum quadrature amplitude modulation (DSSS - QAM) system in AWGN channel when high modulation level (M) is used. At BER=10 - 3, 16, 256 ary DSSS - QAM achieve gains in Eb/N0 of about 7dB and 0.8dB in comparison with 16, 256 - ary ICM respectively because the modulation level is low. While 1024, 4096 and 16384 - ary ICM achieve gains in Eb/N0 of about 6dB, 10dB and16.5dB in comparison with 1024, 4096 and 16384 ary DSSS - QAM respectively because the modulation level is high. Furthermore, a modified version of ICM that uses BPSK modulation and one chaotic signals source together with MACE technique is proposed to reduce the implementation cost named as BPSK - ICM scheme. Simulation results confirm that, BPSK - ICM has a comparable BER performance to the DS - SS system in AWGN channel.Secondly, the bifurcation parameter of a chaotic signal has been estimated accurately by utilizing the ergodic properties of a chaotic dynamical signal. In BPSK ergodic chaotic parameter modulation (BPSK - ECPM) scheme, the information signal modulates the bifurcating parameter of the chaotic signal. A mean value estimation technique is used at the receiver to retrieve the original information accurately. This method minimizes the computational complexity of the receiver; thereby, reduces the total implementation cost.Simulation results show that, at BER=10 - 3, BPSK - ECPM scheme achieves gains in Eb/N0 of about 1dB, 1.5dB, 5.2dB, 6.5dB, 9dB, 10 dB and 11 dB, as compared with CSS, CC,FM - DCSK, DCSK,CSK,COOK and QCSK schemes respectively in AWGN channel. While in Rayleigh fading channel, at BER=10 - 3, BPSK - ECPM achieve gains in Eb/N0 of about 4.8dB, 5.8dB, 6.5dB and 11.8dB, as compared with FM - DCSK,CSS,CC and DCSK schemes respectively. Furthermore, BPSK - ECPM scheme outperforms conventional chaotic modulation systems in the presence of synchronization error and high data rate problems. Finally, BPSK - ECPM scheme shows a good recovery performance of image signal in multipath fading channel for intelligent transportation system (ITS).

تطبيق الشبكة العصبية في تكوين الشعاع المتكيف لنظام الهوائي الذكي == Neural Network Application In Adaptive Beamforming For Smart Antenna System

Author name: سليمان احمد غازي
Supervisor name: عضيد حسن سلومي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
Abstract: انظمة الهوائيات الذكية تعمل على تحسين الاداء وزيادة في السعة لانظمة الاتصالات المتنقلة. ويمكن لانظمة الهوائيات الذكية حل مشكلة نظام الاتصالات المتنقلة مثل التدخل في نفس القناة، والتاخير الحاصل نتيجة الانتشار والمسارات المتعددة التي تاخذها الاشارة عن طريق | The smart antenna systems are promise to provide performance improvement and capacity increasing for the base station of mobile communication systems. Smart antenna systems can solve the problem of mobile communication system such as co - channel interference , delay spread and multipath by an advance signal processing technology called beamforming. In this work artificial neural networks (Feed Forward Neural Network (FFNN) and feedback Elman Recurrent Neural Network (ERNN) ) are used for smart antenna adaptive beamforming for one and multiple targets.Neural network is used to calculate the optimum weights of antenna array to adapt the radiation pattern of the antenna array by directing multiple narrow beams toward the desired users and nulling interference or unwanted users. FFNN and ERNN are trained by supervised backpropagation learning algorithms, FFNN was trained by using Levenberg - Marquardt (lm),Resilient Back - Propagation (Rprop), Gradient descent with momentum and adaptive learning rate (gdx), Gradient descent and adaptive learning rate (gda) and biasing regulation(br), while lm and Rprop are used to train ERNN..The simulation results show that the best performance of smart antenna adaptive beamforming for one and multiple targets is obtained when the NN (FFNN and ERNN) trained by lm algorithm as compared with other algorithms, since it consider the fastest supervised training algorithm but with more memory requirement. Where the performance of FFNN training phase based (lm) algorithm for single target for five element uniform linear array antenna is [2.746641e - 14] at epoch 27 with best validation performance and best test performance approximately equal to the best training performance. While The performance of ERNN training phase based lm algorithm for single target is [1.121938e - 14] at epoch 38 with best validation performance equal to [1.682442e - 14] and the best test performance is [3.363946e - 14].The neural network model in adaptive beamforming are compared with smart antenna adaptive beamforming based on Least Mean Square (LMS) algorithm, and gave better performance than LMS.

تحليل اخفاء الصور باستخدام الاحصاءات ذات المرتبة العالية == Image Steganalysis Using Higher Order Statistics

Author name: عمار موفق يعقوب يوسف دخان
Supervisor name: ماهر خضير العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
First pages:

تحسين تخمين الموقع الزاوي للهدف باستخدام الخوارزمية الجينية == Improvement Of Target Angular Location Estimation In Track-While-Scan Radar System Using Genetic Algorithms

Author name: حارث ماجد صالح الدليمي
Supervisor name: وليد خالد محمد علي | محمود طاهر محمد علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University
Language: English
University location: Baghdad
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
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:

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
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:

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
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:

Development Of Interprocess Communication Simulation For Distributed SCADA System

Author name: نادية اسماعيل
Supervisor name: sarkout N.Abdulla | Nazar AI rawas
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:

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
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:

ضغط الكلام باستخدام ترميز التنبؤ الخطي في مجال تحويل المويجة == Speech Compression Using Linear Prediction Coding In Wavelet Domain

Author name: مصعب تحسين صلاح الدين
Supervisor name: ماهر خضير محمود العزاوي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تصحيح الخطا لبيانات كلام مضغوطة بــ سيلب == Error Correction For Speech Compressed Data Using CELP

Author name: محمد حميد خضير الدركزلي
Supervisor name: خميس عواد زيدان
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:

تصميم ومحاكاة هوائي جزئي متعدد النطاق الترددي للاتصالات اللاسلكية == Design And Simulation Of Multiband Fractal Antenna For Wireless Communication

Author name: ماهر حسين حمد
Supervisor name: عصام محمود عبد الباقي | جواد كاظم علي
General topic: Electrical, Electronic and Communications Engineering
Specific topic: Electrical Engineering
Degree: Master
University: Mustansiriyah University - College Of Engineering - Department Of Electrical Engineering
Language: English
University location: Baghdad
First pages:
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