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تصميم وتوصيف هوائي تيرا هرتز باستخدام الجرافين كموصل مغناطيسي اصطناعي == Design and Characterization of THz Antenna Using Graphene - Based Artificial Magnetic Conductor

Author name: حسين علي عبد النبي
Supervisor name: رفعت طالب حسين | رعد سامي فياض
Specific topic: Communications Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

تحليل اداء قبول الاتصال في تعدد الوصول بتقسيم الترميز الهاتف الخلوي == Performance Analysis of Call Admission Control in WCDMA Cellular Phone

Author name: حسين علي حسين
Supervisor name: وائل عبد الحسن هادي
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم وتنفيذ حوسبة حسابية خاصة == Desing and Implementaion of Private Could Cmputing

Author name: حسن عبد الامير خلف
Supervisor name: ابتسام رحيمة كريخي
Specific topic: Communications Engineering
Degree: Higher Diploma
Language: English
University location: Baghdad
First pages:

تحسين الاداء لنظام الاتصالات LTE باستخدام تقنية التشفير LDPC == Performance Enhancement of LTE Communication System by Using LDPC Encoding Technique

Author name: امجد علي جاسم
Supervisor name: وائل عبد الحسن هادي
Specific topic: Communications Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

تخطيط وامثمة شبكات LTE وWiMAX لمدينة بغداد == PLANNING AND OPTIMIZATION OF WiMAX AND LTE NETWORKS FOR BAGHDAD CITY

Author name: اسيل حميد النقاش
Supervisor name: عايد السامرائي | هيام الياسري
Specific topic: Communications Engineering
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

تمثيل الكيبل الضوئي احادي القناة لتعويض التشتت باستخدام طرق تعويض مختلفة == Simulation of Single Channel Optical System to Compensate Dispersion by using Different Compensating Methods

Author name: احمد علاء عبد الامير
Supervisor name: حيدر مالك عبد الهادي
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم وتنفيذ نظام استشعار للطاقه للراديو الادراكي == Design and Implementation of Energy Sensing System for Cognitive Radio

Author name: احمد عبد الرضا ثابت
Supervisor name: Hadi T. Ziboon
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم هوائي جزيئي ذو نطاق ترددي فائق الاتساع == Design of Ultra Wideband Fractal Antenna

Author name: احسان محمد حسین عباس
Supervisor name: جمال محمد رسول
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تقييم اداء انظمة الاتصالات اللاسلكية للمركبات == Evaluation Performance of Wireless Vehicular Communication Systems

Author name: اباء عبد الزهرة جعفر
Supervisor name: اشواق قاسم حميد
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

INVESTIGATIONS ON NON - LINEAR FEEDBACK SHIFT REGISTERS AND THEIR APPLICATIONS IN STREAM CIPHERING SYSTEMS

Author name: ali sadik abdul - hadi
Supervisor name: SAMIR M. SAID
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

مرشح حجب متعدد الحزم مبني على اساس الهندسة الجزيئية == Fractal based multi-band reject filter

Author name: حيدر صلاح احمد
Supervisor name: جواد كاظم علي | علي جبار سالم
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم مرشحات امرار حزمة BPFs مصغرة بتقنية دليل الموجة المطبوع SIW لاغراض التطبيقات اللاسلكية == Design of Compact Substrate Integrated Waveguide (SIW) Band Pass Filters (BPFs) for Wireless Applications

Author name: اية نبيل عبد الزهراء
Supervisor name: علي جبار سالم
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم هوائي مصغر ذي نطاق ترددي فائق العرض UWB لتطبيقات منظومات الاتصالات == Design of Compact Antenna for Ultra-Wide Band Communication Applications

Author name: محمد رشيد حسين
Supervisor name: جواد كاظم علي
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تقييم سلامة التقاطعات ذات الاشارة الضوئية باستخدام تقنية التعارضات المرورية == Safety Assessment of Signalized Intersections Using Traffic Conflicts Technique

Author name: رغد زكي عبد المجيد
Supervisor name: حسين علي عوض
Specific topic: Communications Engineering
Degree: Doctorate
Language: English
University location: Baghdad

تصميم و تصنيع هوائي شقي من النوع الجزئي لتطبيقات الاتصالات اللاسلكيه ثنائية النطاق الترددي == Design and Fabrication of Printed Fractal Slot Antennas for Dual - band Communication Applications

Author name: سيفان فهمي عبد الكريم
Supervisor name: جواد كاظم علي
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

دراسة وتحليل الاظمحلال في قناة النظام الخلوي GSM == A study and analysis of fading in GSM mobile channel

Author name: علاء عدنان سليم
Supervisor name: عايد خلف السامرائي
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:

تصميم ترميز تحويل لوبي في القنوات الاسلكية == Design of Luby Transform Code Over Wireless Channel

Author name: نبيل احمد مصدق
Supervisor name: وائل عبد الحسن هادي
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: ترميز التحويل لوبي) هو نوع من الترميز النافوري يعمل بدون اي معلومات عن القناة. في هذا العمل، تم تصميم LT code)) باستخدام ماتلاب، التصميم يتكون من ثلاثة اجزاء ( Encoder ,Decoder, channel ). في الجزء الخاص بتصميم الـ (Channel ) استخدمنا (( flat fading ch | Luby transform code (LT Code) is a type of fountain codes operating without any information about channel. In this work, LT code design of LT code implemented by using Mat lab as simulation software, our design consists of three parts (encoder, channel and decoder). In the channel design, flat fading channel will be used as a noisy channel to measure the performance of LT code over this type of channels. From the result obtained, SNR improvement by (30dB) at (BER=?10?^( - 4)) compared with data effect by the fading channel without coding with BPSK modulation model under different values of degree of distribution (d). Other type of modulation model (QPSK) used to measure the effect of changing the modulation type on the code performance. From the results obtained, SNR improvement by (31dB) at (BER=?10?^( - 4)) compared with data effect by the fading channel without coding. The degree of distribution (d) is a critical point of design, two types of distribution presented in this work, robust soliton distribution (RSD) and ideal soliton distribution (ISD). (ISD) works poorly in practice, (RSD) is a practical way used to get the degree of distribution in design by adding two extra parameters (c and ? ) which provide the spike element (k/R) in high degree distribution to ensure the continued of decoding process. As a result obtained the value of (c) has a major effect on the spike position on high degree (c=0.15,k/R=10 and c=0.2,k/R=7) with selective value of ?=0.5.The successful decoding probability for two types of degree distribution is very important, the value of successful decoding probability for (ISD) for low number of encoding packets (50 - 100) packet is greater than the value of successful decoding probability for (RSD). In the high number of encoding packets (>150) the value of successful decoding probability for (RSD) is greater than the value of successful decoding probability for (ISD).Encoding time for two type of distribution also discussed in this work, based on the results obtained the encoding packets time when using (RSD) is less than the encoding packets time when using (ISD).

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
Specific topic: Communications Engineering
Degree: Master
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
Specific topic: Communications Engineering
Degree: Master
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
Specific topic: Communications Engineering
Degree: Master
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.

تقليل التاثيرات اللاخطية في منظومات التقسيم المتعدد للطول الموجي العالية الكثافة == Mitigation of Fiber Nonlinearity Effects In Ultra High - Dence WDM System

Author name: سيف حسام عبد الواحد
Supervisor name: علي يوسف فتاح
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: The optical signal is severely degraded when transmitted in the fiber due to both the linear and nonlinear distortions. It is well known that, the linear distortions in single mode fiber include chromatic dispersion (CD) and polarization - mode dispersion (PMD) while self - phase modulation (SPM), cross phase modulation (XPM) and four - wave mixing (FWM) are considered the most among nonlinear distortions. To deal with the nonlinear impairments, a number of techniques, such as electronic equalization, pre - coding, digital back - propagation(BP), pre - chirping, optical phase conjugation (OPC) and nonlinearity management, are developed and improved. In the present work, a method called Fractional Fourier Transform (FRFT) has been applied to mitigate fiber nonlinearity impairments. The Fractional Fourier Transform is a time - frequency distribution and an extension of the classical Fourier transform. Time domain FRFT can be implemented by using time lens according to the optical time - space duality theory. The modulated optical pulses will be pre - distorted by an FRFT module before being launched into fiber links. In this work, 10 Gb/s optical fiber system with five spans, each of length 60 Km, for three types of modulation formats (Return - to - Zero Differential Phase Shift Keying (RZ - DPSK), Return - to - Zero Differential Quaternary Phase Shift Keying (RZ - DQPSK) and Carrier - Suppressed Return - to - Zero (CSRZ)), single and multi - channel transmission systems are designed and simulated using “OptiSystem (2011) version 10.0” software package. In order to analyze the transmission performance of the simulated systems without and with FRFT, a set of eye diagrams, optical spectrum visualizers, Q - factor versus input power and Bite Error Rate (BER) versus Signal to Noise Ratio (SNR) curves are presented to evaluate the influence of FRFTon the system performance. For CSRZ modulation format the Q - factor for single channel system at 0 dBm (input power) was 43.5 without FRFT and 78 with FRFT. The BER of sixteen channel system (channel No.8) at bit rate 10 Gb/s per channel, 300 Km link length of CSRZ modulation format with channel spacing of 50 GHz at SNR 10 dB without FRFT is 10 - 4.8 and 10 - 7.4 with FRFT. The BER of thirty two channel system (channel No.16) at bit rate 10 Gb/s per channel, 300 Km link length of CSRZ modulation format with channel spacing of 50 GHz at SNR 10 dB without FRFT is 10 - 4.6 and 10 - 6.4 with FRFT. The BER of thirty two channel system (channel No.16) at bit rate 10 Gb/s per channel, 300 Km link length of CSRZ modulation format with channel spacing of 25 GHz at SNR 10 dB without FRFT is 10 - 2.56 and 10 - 3.24 with FRFT.

خوارزمية جديدة لنظام اخفاء المعلومات == New Algorithm For A Steganography System

Author name: مروة جليل محسن
Supervisor name: اثير علاء صبري
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: This thesis presents a new steganographic algorithm for embedding encrypted secret image in grayscale and color images to provide high level security of data for communication over unsecured channels.The proposed algorithm combine the features of Cryptography and Steganography. The hidden secret message capacity, stego - image quality and security are three important conditions for data hiding technology. According to these requirements, an effective security protection with high hiding capacity steganographic algorithms are proposed based on frequency domain of the cover and the secret image.The proposed algorithm first analyzes the secret image into its frequency components using Discrete wavelet transform (DWT) , Wavelet packet transform(WPT) , Multiwavelet transform(MWT) , and slantlet transform(SLT) , respectively. Then the low frequencycomponent of the secret image is encrypted using Advanced encrypted standard (AES) method and then embedded in the insensitive mid and high sub - bands obtained from the cover image after applying these transformations (mentioned earlier) on it. The embedding method used in this thesis is LSB (Least significant bit ) method. The resulting stego image from different algorithms are then compared..The effectiveness of the proposed algorithm has been estimated by computing Mean square error (MSE) ,signal to noise ratio (SNR), Peak Signal to Noise Ratio (PSNR) and the capacity.The best algorithm is obtained by using 2level - DWT for cover image and 1level - DWT or WPT for secret image because the capacity of the hidden secret data and stego image quality are improved. The embedding image reaches to half the size of cover image at same time PSNR reach to 62 dB and MSE about 0.036 and this is better than many other existence algorithms.By both objective and subjective observations, the resultant stegoimage that will be transmitted does not draw any suspicion, so the main goal of steganography is achieved..The language used for testing the algorithms is MATLAB R2013a, with a computer of the following specification ; Processor : Intel(R) Core(TM) i5 CPU M430 @ 2.27GHz and RAM - 3GBytes.

اخفاء العلامة المائية الرقمية باستخدام تحويل الموجيات ذات عامل جودة قابل للتعديل == Digital Watermarking Based On Tunable Q - Wavelet Transform

Author name: هاجر احمد ابراهيم
Supervisor name: اثير علاء صبري
Specific topic: Communications Engineering
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: لقد دخلنا عصر حيث المعدات غير المكلفة متوفرة ويمكن من خلالها انتاج نسخ كاملة من المواد المتعددة الوسائط الرقمية مثل صوتيات بجودة القرص المضغوط ونشر صور عالية الجودة او مقاطع الفيديو الرقمية. من خلال هذه البيئة اصبح من السهل على الجهات غير المختصة انتاج ن | We have entered an era where inexpensive and readily available equipment can produce perfect copies of digital multimedia materials, such as CD - quality audio, publication - quality images, or digital video. In this environment, it has become easier for malicious parties to make salable copies of copyrighted content without compensation to the content owner.Many media content owners are concerned about the potential loss of revenue from multimedia piracy, especially when the content will be exposed to the Internet. Digital watermarking is seen by many as a potential solution to this problem.In this thesis, two proposed methods one for grayscale image watermarking and the other for color image watermarking are suggested. They require the original image for watermark extraction and they are belonging to the wavelet domain watermarking. They exploit the Tunable Q_Wavelet Transform. Therefore, different cases are performed to identify the best among them for the proposed application. As a result of the testing process, the best case is founded when ( Q=4, r=8, J=28). The first proposed method can be used with applications requiring high degree of imperceptibility and high security. The embedding process of this method is based on adding the pseudorandom watermark bits in the largest TQWT coefficient.The second proposed method is more robust against distortions than the first proposed method and is characterized by an acceptable degree of imperceptibility and high security. The embedding process of this method is based on adding the compound watermark image to the original color image.They are performed using MATLAB7 programming language. Different images are tested and the watermark is extracted exactly from the watermarked images.The Peak Signal to Noise Ratio “PSNR” using best case for the two proposed methods is found (77.97) dB for the first method and (51.14) dB for the second method.

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
Specific topic: Communications Engineering
Degree: Master
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
Specific topic: Communications Engineering
Degree: Master
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.
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