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بناء معيد ترميز تكراري شبه مثالي للاشارات المرمزة المعتمدة على مخطط تانر Implementation Of Modified Suboptimal Iterative Decoding For Tanner - Graph Based Coded Signals

اسم المؤلف: محمد ثامر نصر

اسم المشرف: احمد عبد الكاظم حمد

الموضوع العام: هندسة الكهرباء والالكترون والاتصالات

السنة: 2016

الموضوع الدقيق: هندسة الالكترونيك والاتصالات

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

المستخلص: في هذا العمل, تم اقتراح خوارزميتين لتحسين اداء معيد الترميز التكراري التجميعي. الاول انجز باضافة رموز ارشاد بين سيل البيانات التي تدخل الى المرمز. في هذه الطريقة, رموزالارشاد ترمز مع البيانات المدخلة (رموز الارشاد المرمزه او الداخليه) مقارنة بالطريقة الاع | In this work, two algorithms were suggested in order to improve the performance of systematic RA decoding. The first one was accomplished by the insertion of pilot symbols between the data stream that entering the encoder. In this way the pilot symbols are encoded along with the input data (encoded or internal pilots) in contrast to the usual way where pilots are inserted after encoding (unencoded or external pilots). The positions where pilots should be inserted are chosen in such a way that to improve the minimum Hamming distance and/or to reduce the error coefficients of the code. Moreover, the known pilots have higher reliability than data and can significantly improve the initial decoding.The second proposed algorithm includes the utilization of the inserted pilots to estimate scaling (correction) factors. Two - dimensional (2D) correction system was suggested in order to enhance the performance of traditional Minimum - Sum (MS) decoding of regular RA codes. By calculating the mean square difference (MSD) between the values of received pilots and the a - posteriori data of bit and check node related to them, which are created by the MS decoder, an adaptive method can be achieved for getting the correction factors.Since encoded pilots in systematic RA code are embedded in data, it is possible to puncture all or part of them to increase the code rate. The pilots still have their effect on increasing the minimum Hamming distance.Extensive simulation tests reveal that the suggested quasi - optimal algorithms supply error performance be able to compare as Sum - Product (SP) decoding whilst maintain less complexity. Practical experiments are carried out by utilizing the capability of data acquisition toolbox supported by MATLAB to provide a hardware interface with the computer sound card. Here, the sound card plays the role of ADC and DAC converter in the physical layer. A different graphical user interfaces (GUI) are designed for the transmitting and receiving terminals to facilitate the selection of different code options. Signals are transmitted over wireless channel using a 2.4 GHz band indoor audio tranceiver. According to the aquired results, the modified coding system outperforms the original one when it is tested over AWGN and fading channels. An improvement may be realized about 1.5 dB and 1.3 dB at BER=?10?^( - 5) for punctured and unpunctured systematic (50,35,3,7) code with adaptive scaling, with three encoded pilots over AWGN channel and about 3.4 dB and 3.3 dB at BER=?10?^( - 4) for punctured and unpunctured systematic (50,35,3,7) code with constant scaling, with two encoded pilots over fading channel.

مراقبة انذار المرضى عن بعد الزمن الحقيقي اعتمادا على الصحة الالكترونية الصحة العنكبوتية الصحة الخلوية وشبكات التحسس اللاسلكية حالات الدراسة موضع منام المريض سكر الدم استجابة الجلد الكلفانية والتخطيط العضلي Remote Patients Monitoring / Alarming In Real Time Based On E - Health / I - Health / GSM - Health And WSN, (Case Study : PP, BG, GSR And EMG

اسم المؤلف: علي جاسم رمضان

اسم المشرف: سمير جاسم محمد محمود شاكر نصر

الموضوع العام: هندسة الكهرباء والالكترون والاتصالات

السنة: 2014

الموضوع الدقيق: هندسة الالكترونيك والاتصالات

الدرجة: ماجستير

الجامعة: جامعة بابل - كلية الهندسة - قسم الهندسة الكهربائية

اللغة: الانكليزية

مكان الجامعة: بابل

الصفحات الاولى:

المستخلص: Patient's health monitoring / diagnosing systems have become the focus of attention of researchers today. At the present time, the researchers are dealing with the E - health fields to develop and improve the healthcare systems and they work to combine the GSM and Internet technologies together.In the presented work, the researcher designed a portable real time wireless medical system for monitoring / diagnosing the patients' status based on E - health / GSM - health / I - health and wireless sensor network (WSN) under ZigBee protocol, and to support alarming and printing of medical reports subsystems.The presented system consists mainly of four subsystems, which are sensing & data transceiver, base station (BS), GSM and Internet. Where sensing & data transceiver subsystems be in the patients' lobbies and connected remotely with the base station (BS) subsystem in the wireless sensor network that collect and display the sensing data in it. Also in the designed system, the GSM and Internet technologies are inserted practically in the network.The implemented system measures the biomedical data utilizing a group of sensors that are not available in the country's hospitals in such integrated system, which are the patient position sensor (PPS), galvanic skin response sensor (GSR), blood glucose sensor (BGS), and electromyography sensor (EMG). Moreover, the system has the ability to add many other sensors.In the proposed system, three nodes (lobbies) are considered according to the facilities available, but it can monitor / diagnose unlimited patients' numbers.The system monitors the sleep position and skin conductance (indicator to patient's calm) of the patients in real time with alarm for each abnormal case in the base station (BS) and in lobbies, and it also follows up the glucose rate in patient's blood and diagnose the electromyography (muscle and nerve) status.The GSM subsystem (GSM - health) is used for remotely following - up the patients' status by sending SMS alarm in time for any abnormal case of the patient's sleep position and skin conductance, also it has ability to send the glucose data to doctor's phone. All these services are performed by using a personal phone device only without using any additional GSM modem or other apparatus, so this method reduces cost, complexity and delay time of the system that's done by interfacing the phone with the PC directly via USB port and the messages sending procedure executed using special SMSs AT commands, so the doctors become able to communicate with BS using SMS or voice calling to give the fast and direct necessary guidance.The Internet subsystem (I - health) is another excellent service for the presented system, by which remotely following - up the glucose levels by uploading the glucose data to a specific web site. It is performed by designing a web site that is programmed using VB.NET and ASP.NET languages. of course, user login feature is added to protect the privacy of patients and feedback comments feature between the doctors and patients to take the important guidance.The system has ability to introduce a printed hard copy report about the patient's electromyography status or result and blood glucose levels, by utilizing VISUAL BASIC program. Moreover, it performs searching process about the active nodes in network, this means that it detects any new node (new patient) and put it in service. In addition, the system records the patient's information and stores his health data for any archiving process or statistical study.The main hardware that is used in the implemented system includes MCUs, sensors and transceivers, and used the LABVIEW program to display the data in its GUI windows in the computer of BS.The system has been implemented practically at low cost and low power, gave expected and accurate results, and presented to the specialists doctors and they have expressed their conviction and effectiveness of the system in practice.