A probabilistic approach to early communication performance estimation for electronic system-level design

Today\u27s embedded system designers face the challenges of ever increasing complexity and shorter time-to-market deadlines. System-level methodologies emerge to meet these challenges. Refinement-based methodologies, such as the SpecC methodology and Transaction Level Modeling, continue to gain popularity in the embedded system designers\u27 community. However, as more communication-dominated applications and architectures appear in the market, designers find that the lack of models allowing system-level communication analysis is a major limiting factor in current system-level design methodologies. Thus, modeling for system-level communication analysis is key for a design methodology to thrive with today\u27s embedded system designers. This work presents a new approach to system-level modeling that allows better communication analysis earlier in the design process. This approach defines a new model that utilizes random variables to include the communication details at higher abstraction levels. This work proposes a probabilistic model to include and evaluate the system communication features in the higher abstraction level. Guidelines to include the proposed model into a refinement-based methodology are presented, and methods for performance estimation are shown

Ad Hoc Network Architecture for Multi-Media Networks

The desire for more intelligence in the battlefield has given rise to the idea of routing video images over wireless sensor networks. This would apprise combat decision makers with actual images of battlefield developments and allow them to make sound decisions. To achieve this objective, the characteristics of video traffic must be studied and understood. This thesis focuses on evaluating the possibility of routing video images over a wireless sensor network. Video traffic is modeled and simulations are performed via the use of the Sun Small Programmable Object Technology (Sun SPOT) Java development kits configured in three different network topologies: the star topology, binary tree topology and chain topology. It is known that video traffic is self similar and can be obtained by aggregating a large number of On-Off message sources. Hence, an On-Off model using Pareto distribution function is used to model video traffic over the network. In this thesis four self-similar shaping parameters, i.e., alpha(On) = 1.2, 1.4, 1.7 and 1.9 are used in the simulations. The performance of each topology is evaluated based on parameters like mean throughput, mean interarrival time, mean packet drop, and mean delay.http://archive.org/details/adhocnetworkarch109452988Singapore Armed Forces author.Approved for public release; distribution is unlimited