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Full-Text Articles in Computer Engineering
Turbo Codes For Wireless Mobile Communication Systems Applications, Moataz M. Salah
Turbo Codes For Wireless Mobile Communication Systems Applications, Moataz M. Salah
Theses and Dissertations
Research in coding theory has seen many proposals aimed at the construction of powerful codes using block and convolutional codes. Recently, a new forward error control code, known as turbo code, was introduced. This new code yields very good performance (near the Shannon limit) with relatively simple component codes and large interleavers in combination with an iterative decoding process. Among the most important applications of turbo codes are wireless mobile communication systems. A significant performance metric for this application is the minimization of end-to-end delay. In this dissertation, different ways to enhance the performance of turbo codes with short frames …
A Methodology For Integrating Tools In A Web-Based Environment, Musa Serdar Arslan
A Methodology For Integrating Tools In A Web-Based Environment, Musa Serdar Arslan
Theses and Dissertations
Web-based technologies are evolving very rapidly. New technologies are introduced very frequently in the realm of the Web and Internet. This evolution also affects database management systems (DBMSs). Almost all DBMS vendors are making their systems "Web-enabled." The Internet and the World Wide Web are getting more important and bigger than ever. Because of the increase in the importance of the Internet and the Web, migrating old applications and tools to a web-based environment is becoming more important. When migrating old applications or tools to the web-based environment, integration of tools becomes an important issue. In this research, a step-by-step …
A Distributed Agent Architecture For A Computer Virus Immune System, Paul K. Harmer
A Distributed Agent Architecture For A Computer Virus Immune System, Paul K. Harmer
Theses and Dissertations
Information superiority is identified as an Air Force core competency and is recognized as a key enabler for the success of future missions. Information protection and information assurance are vital components required for achieving superiority in the Infosphere, but these goals are threatened by the exponential birth rate of new computer viruses. The increased global interconnectivity that is empowering advanced information systems is also increasing the spread of malicious code and current anti-virus solutions are quickly becoming overwhelmed by the burden of capturing and classifying new viral stains. To overcome this problem, a distributed computer virus immune system (CVIS) based …
A Performance Analysis Of A Joint Lmds/ Satellite Communication Network, Ronald J. Zwickel
A Performance Analysis Of A Joint Lmds/ Satellite Communication Network, Ronald J. Zwickel
Theses and Dissertations
The goal of this research is to provide a performance analysis of a joint terrestrial/ satellite communication network. The systems of interest are the Local Multipoint Distribution Service (LMDS) terrestrial system and the proposed Teledesic satellite network. This analysis is performed using the OPNET network simulation tool. Simulations are run for twelve separate scenarios involving three factors which include: number of users, modulation type, and Quality of Service (QoS). The key metrics for characterizing simulation scenarios are the end-to-end delay, bit error rate, and average system throughput. The results obtained display the benefit of improved throughput, approximately 20 Mbps for …
Modeling And Simulation Of Communication Systems In Opnet, David M. Banker
Modeling And Simulation Of Communication Systems In Opnet, David M. Banker
Theses and Dissertations
This research aims to present accurate computer models of a communication link and a Super High Frequency (SHF) radio communication system. Network Warfare Simulation (NETWARS) is a J-6 initiative aimed at modeling all communication traffic in the Department of Defense (DoD) for testing and analysis of specific real world scenarios. The AN/TSC-94 is a SHF radio system with satellite communication capabilities. The AN/TSC-94 incorporates a Direct Sequence Spread Spectrum (DSSS) radio link for certain Anti-Jam (AJ) features. A DSSS spreads' signal power over a large bandwidth, reducing power previously concentrated within the original system bandwidth. The simulations were performed using …
Mission Route Planning With Multiple Aircraft & Targets Using Parallel A* Algorithm, Ergin Sezer
Mission Route Planning With Multiple Aircraft & Targets Using Parallel A* Algorithm, Ergin Sezer
Theses and Dissertations
The general Mission Route Planning (MRP) Problem is the process of selecting an aircraft flight path in order to fly from a starting point through defended terrain to target(s), and return to a safe destination. MRP is a three-dimensional, multi-criteria path search. Planning of aircraft routes involves an elaborate search through numerous possibilities, which can severely task the resources of the system being used to compute the routes. Operational systems can take up to a day to arrive at a solution due to the combinatorial nature of the problem, which is not acceptable, because time is critical in aviation. Also, …