Defense Notices

This work presents the design and development of a genetic algorithm to generate long range transmit codes with low autocorrelation side lobes for radar. The genetic algorithm described in this work has a parallel processing design and has been used to generate codes with multiple constellations for various code lengths with low estimated error of a target profile.

As the World Wide Web continues to evolve as the preferred choice for information access it is critical that its utility to the user remains. Latency as a result of network congestion, bandwidth availability, server processing delays, embedded objects, and transmission delays and errors can impact the utility of the web browser application. To improve the overall user experience the application needs to not only provide feedback to the end user about the latency of links that are available but to also provide them decision controls in the retrieval of the web content. This thesis presents a background and related work relating to latency and web optimization techniques to reduce this latency and then introduce an improvement to the "latency aware" Mozilla Firefox extension which was originally developed by Sterbenz et. al., in 2002. This these describes the architecture and prototype implementation, followed with an analysis of its effectiveness to predict latency and future work.

Radar systems can fulfill a wide range of remote sensing missions, from aircraft tracking, to rainfall rate measurements, to automobile cruise control assist. The history of radar is full of innovation and a drive to "get the most" out of a system. History, however, is also full of simplifying assumptions made along the way to make certain problems tractable. In some sense, engineers have historically traded performance for tractability. Antenna arrays and their accompanying electromagnetics is one such area that is ripe to have its simplifying assumptions pealed back in an effort to extract even more performance. This can be demonstrated by developing high fidelity electromagnetic (EM) models of a radar array and showing that existing array processing algorithms based on simplified models are operating at a degraded performance level. These high fidelity EM models can then serve as a basis to enhance the performance of these algorithms. This work will specifically examine integrating a blind calibration process into the Re-Iterative Super Resolution (RISR) Direction of Arrival (DoA) algorithm to improve RISRs performance, show that the misapplication of the reciprocity theorem is holding back radar array processing algorithms, and investigate the possibility of leveraging recent results showing non-linearities in off-boresight emissions to improve clutter mitigation.

Many applications use a variety of components both at the middleware and OS as part of their execution and systems are designed to provide these applications with high availability and specific qualities of service intended for specific application semantics. To provide these features, systems must be developed that exercise precise control over computation 
behaviour. This thesis proposes a mechanism where the structure of the computation and its behaviour can be discovered by tracing the system calls that an application makes during the period of its execution in real time using Data Streams and Computation Component Set Manager frameworks. This thesis also demonstrates the integration of computation behaviour information with Hierarchical Group Scheduling framework to achieve precise control over the execution of the application through arbitrary scheduling semantics.