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تمييز الحروف العربية المعزولة المكتوبة بخط اليد باستخدام الشبكات العصبية == Recognition Of Isolated Handwritten Arabic Letters Using Neural Networks

Author name: نهلة ظاهر حبيب بهية
Supervisor name: منذر نعمان التكريتي
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: يتناول هذا البحث مشكلة تمييز الحروف العربية المعزولة المكتوبة بخط اليد باستخدام الشبكات العصبية. ان نظام تمييز الحروف العربية المقترح يتكون من ثلاث مراحل وهي : مرحلة مسح صور الحروف العربية ثم مرحلة معالجة الصور واخيرا مرحلة التدريب والتصنيف.ان المرحلة الاخ | This thesis presents an algorithm for recognition of an off - line isolated handwritten Arabic letters using neural networks.The handwritten recognition system present in this work consists of three modules : - 1 - Arabic letter scanning module 2 - Arabic letter preprocessing module 3 - Learning and recognition module.The proposed neural network in the third module is trained in two stages : The first stage employs Self - Organizing Map learning algorithm for clustering the input pattern, which are based on a database of 196 letters collected from 7 independent persons.In the second stage each of the similar output cluster is considered as a subnet introduced to neural network trained by Back - propagation learning algorithm for classification. Several networks architecture are designed in the second stage using 1 - hidden and 2 - hidden layers with 5 and 28 output nodes in the output layer with different number of hidden nodes and learning rate.To examine the efficiency of the system a database of 196 letters collected from other 7 independent persons are used, (in order to test the ability of the trained network to generalize). The results show that clustering the input pattern, using 1 - hidden layer and 28 nodes in output layer improve the network performance. The system was implemented using (IBM - PC) of type Pentium 3.The programming language used to design the system was c++ version 5.02.

استراتيجية السيطرة على المقوم ثلاثي الاطوار المضمن بعرض النبضة (PWM) نوع رافع للجهد ولمصدر تغذية متغير الحالات

Author name: منتظر كاظم عبد الله
Supervisor name: تركي كحيوش حسن
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: In this thesis, a proposed control strategy is presented to improve the performance of the PWM boost type rectifier when operating under different supply voltage conditions (balanced, unbalanced, and distorted three - phase supply voltages). The proposed control strategy is classified into two parts, the first part is voltage controller and the second part is current controller. In the voltage controller, Repetitive Controller (RC) is used to reduce the even order harmonics in the regulated output dc voltage (5.62V (P.P.)) so small output capacitor (480µF) is used instead of large capacitor (920µF) that is used with the conventional controller (PI controller connected in series with a LPF). RC also reduces the even order harmonics (0.014A (P.P)) which appears in the reflected dc current (IMAX), this leads to reduce the odd order harmonics (0.01A) which appears in the input currents. While in the current controller, enhanced Phase Locked Loop (EPLL) technique is used to obtain sinusoidal and balanced three phases, to construct the reference currents, which are in phase with the fundamental supply voltages Therefore, the supply - side power factor is kept close to unity (0.9036 for extremely distorting case). As a result the calculations of the reference currents in the proposed control strategy does not require Clarke or Park transformations, the same for the calculations of the positive or negative sequence components. A proportional controller is used to give excellent tracking between the line and the reference currents. Using this approach makes the control strategy easy to understand and also it saves calculation time of the control algorithms if implements in real time. The complete system with the proposed control strategy is simulated using Matlab/Simulink (Version 2012). The obtained results for the complete system using repetitive voltage controller are compared to the results of the system with using the conventional voltage controller. The results with the repetitive controller show better responses and stable operation in the steady state under different input voltage conditions, as well as in the transient response under different disturbances.

مبدل فوتوفولطائي مايكروي احادي المرحلة نوع فلايباك المغذي للشبكة == Single Stage Grid - Connected Flyback Photovoltaic Microinverter

Author name: مصطفى عباس فضل
Supervisor name: تركي كحیوش حسن
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: Solar energy systems based on photovoltaic (PV) cells have attracted considerable interest in recent years due to their abilities of clear and seemingly limitless generated energy. Solar energy systems based on microinverter architectures are earning in publicity as they are less prone to shading and PV cell malfunction since each PV panel in the system has its own low power inverter.In this thesis two alternative modes of operation for the current source flyback microinverter are suggested : the discontinuous conduction mode (DCM), where a constant switching frequency (CSF) control method is applied, and the boundary conduction mode (BCM) between continuous conduction mode (CCM) and DCM, where a variable switching frequency (VSF) control method is used. These two control methods are analytically studied and compared in order to establish their advantages as well as their suitability for the development of an inverter for grid - connected PV applications.An optimum design methodology is developed, aiming for an inverter with the smallest possible volume for the maximum power transfer to the public grid and wide PV energy exploitation. The main advantages of the current source flyback microinverter are very high power density and high efficiency due to its simple structure, as well as high power factorregulation. The design and control methodology are validated by Powersimulation software (PSIM) and a laboratory hardware prototype is buildusing analogue and digital devices.The microcontroller type (PIC - 18F45K22) is used to implement perturb and observe (P&O) maximum power point tracking (MPPT) algorithm, and C language is used for programing the microcontroller. The simulation and experimental results are obtained to verify the proposed flyback microinverter.

تحقيق دائرة المعدل الثابت للانذار الكاذب باستعمال منظومة البوابات المنطقية المبرمجة موقعيا == Modified GO - CFAR Implementaion Using FPGA

Author name: مصطفى صبحي كمال
Supervisor name: رفعت طالب حسين | حكمت نجم عبد الله
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: هذه الاطروحة تتعلق بتحليل ومعالجة تاثير الضوضاء المحيطية (Clutter) لمنظومة الرادار النبضي، يتطلب رادار الكشف الالي للهدف استعمال عتبة الية (Adaptive threshold) لتحقيق معدل ثابت للانذار الكاذب وذلك لغرض السيطرة على الانذار الكاذب الذي تسببه تغيرات في الضوض | This thesis deals with the analysis and processing of clutter for pulsed radar system. Automatic target detection radar requires adaptive thresholding achieved by Constant False Alarm Rate (CFAR) circuit in order to control the false alarm caused by variations in clutter background.This work focus on worst radar environment that happens when abrupt variation in clutter background merged with multi - interfering target, to detect target in such environments it need robust CFAR algorithm that excise the target spikes and clutter edges from CFAR window in order to give best possible estimation to the noise background. two important algorithms studied which are CA - CFAR and OS - CFAR algorithms in additional to the modified CA - CFAR algorithm. All these algorithms were simulated with mat lab v6.1 and applied them to three different clutter models that represent different environment cases the CA - CFAR family failed to handle model two and three also OS - CFAR family except OSGO - CFAR that handle all models successfully. For modified CA - CFAR family only modified GO - CFAR handle all models successfully and comparing with OSGO - CFAR the modified GO - CFAR need less hardware and processing time because it did not need sorting process that is essential for OSGO - CFAR. Therefore, the modified GO - CFAR is chosen to implement by using FPGA and another important feature in modified GO - CFAR algorithm that is parallel processing since the spike selection process is done at the same time with summing of samples process that make this algorithm much less in processing time from any other algorithm that work in the same environment. The FPGA chip that used to implement modified GO - CFAR algorithm need only three signals from the radar receiver to mach with the receiver circuit correctly which are time base clock signal period reset trigger signal and the pulse duration time. Therefore, the FPGA chip can work effectively with almost any radar receiver system

مسيطر السرعة المثالي بالاعتماد على المتجه المسيطر لمسوق محرك التيار المستمر عديم الفرش == Optimal Speed Controller Based On Vector Controlled For A Brushless DC Motor Drive

Author name: مصطفى بشار عبد الملك
Supervisor name: تركي كحيوش حسن
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: اصبحت محركات التيار المستمر عديمة الفرش شائعة جدا في الكثير من المجالات مثل في الصناعة والتطبيقات المنزلية؛ وذلك يعود الى مميزاتها العديدة على محركات التيار المستمر ذوات الفرش والمحركات الحثية؛ مثل كفائتها العالية, كثافة قدرتها العالية وحجمها الصغيرنسب | Brushless DC (BLDC) motors have become very popular in various fields such as in industry or home appliances; and that is due to their many advantages over the brushed DC motors and the induction motors such as their higher efficiency, high power density and respectively low volume. The traditional and most popular way to drive BLDC motor is by using six - step or trapezoidal technique. This technique however has several problems such as high torque ripple and high distortion in the currents. This thesis presents a BLDC motor drive system where the performance of the motor is improved on various aspects. The first aspect is to improve the speed response by using particle swarm optimization (PSO) technique to find the optimal parameters of the speed controller. The second aspect is to reduce the torque ripple associated with the traditional driving technique and also improve the dynamic response of the motor by using vector or field - oriented control to drive the motor. The third aspect is improving the total harmonic distortion (THD) of the voltages and currents by using multilevel inverter. The last aspect is driving the motor in sensorless operation for reduced cost and for applications where speed and position sensors cannot be used; this operation uses a flux - linkage observer with a phase - locked loop (PLL) structure to estimate the position and speed of the rotor. The control methods are modeled using MATLAB/Simulink program and the results show that the proposed systems has significant improvement in performance as compared with the traditional technique in terms of speed response, torque ripple and THD of the voltages and currents

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.

تحليل الاشارات المشفرة ثنائيا باستخدام الترشيح الموائم وغير الموائم لتقليل الفصوص الجانبية == Analysis Of Binary - Coded Signals Using Matched And Mismatched Filtering For Sidelobe Reduction

Author name: صلاح حسن عباس
Supervisor name: اسماعيل محمد جابر
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: Various types of binary phase - coded signals are studied in terms of their correlation properties. Then, matched filtering technique as well as mismatched filtering techniques is applied to the codes studied previously in order to reduce the sidelobes of the compressed binary phase - coded signal around the mainlobe, and consequently increase the detection of the received signal. Each filtering technique is performed using programs written by the programming language of MATLAB version 7.4.0.287 (R2007a). White Gaussian noise is introduced in the assessment made to both the filtering techniques and the codes that are adopted in this thesis.The MATLAB programs are tested on various types of binary phase codes that are adopted in this thesis to calculate the criteria to choose the best filtering technique. These criteria are peak sidelobe level, the integrated sidelobe level, and the signal - to - noise ratio loss. Later, the results, which are obtained according to these mentioned criteria, are used to test different filtering techniques on the chosen periodical and aperiodical binary phase codes to choose the best one.It is found that, the optimal peak sidelobe level (PSL) filtering technique is the best filtering technique for the aperiodical binary phase codes in terms of the peak sidelobe level, and in terms of an acceptable signal - to - noise ratio loss. The optimal integrated sidelobe level (ISL) filtering technique comes in the second place.While, it is found that, the mismatched filtering technique is the best filtering technique for the periodical binary phase codes in terms of an acceptable signal - to - noise ratio loss.

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

نظام الاخفاء الصوري المعتمد على تحويل المويجة والاشارات الفوضوية

Author name: سرى فهمي يوسف
Supervisor name: حكمت نجم عبد الله
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:

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
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