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

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

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

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

تحسين التغطية للشبكات الخلوية == COVERAGE ENHANCEMENT OF CELLULAR NETWORK

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

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

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

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

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

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

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

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

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

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

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

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

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