This paper focuses on the interaction and integration of several critical components of a Mobile Ad-Hoc Network (MANET) using smart antenna systems. A MANET is a wireless network where the communicating nodes are mobile and the network topology is continuously changing. One of the central motivations for this work comes from the observed dependence of the overall network throughput on the design of the adaptive antenna system and its underlying signal processing algorithms. In fact, a major objective of this work is to study and document the overall efficiency of the network in terms of the antenna pattern and the length of the training sequence used by the beamforming algorithms. This study also considers in sufficient detail problems dealing with the choice of direction of arrival algorithm and the performance of the adaptive beamformer in the presence of antenna coupling effects. Furthermore, the paper presents strategies and algorithms to combat the effects of fading channels on the overall system.

No abstract

No abstract

In this paper, the problem of sharing resources (slots of an up-link TDMA frame) among real-time heterogeneous variable bit rate (VBR) applications with diverse quality of service (&OS) requirements is addressed. The QoS requirements for each application is defined in terms of a maximum tolerable packet delay and dropping probability; a packet is dropped if it experiences excess delay. The region of achievable QoS vectors -which is central to the call admission problem -is established for policies that are work-conserving and satisfy the earliest due date (EDD) service criterion (WC-EDD policies); such policies are known to optimize the overall system performance. In addition to the determination of the region of achievable QoS vectors, this study leads also to the construction of scheduling policies which deliver any performance in the region established for WC-EDD policies. Finally, an upper bound on the region of QoS vectors that can be achieved under any policy (not limited to the WC-EDD policies) is determined.

This paper introduces the concept of a process model for network engineering and operation, which addresses quality, process, and maturity of the network engineering process. Currently, the state-of-the-art in network engineering may be classi ed as less than formal. The need for a well planned and exercised network engineering process model is essential for the proper growth of the network engineering practices. The current state of the network engineering process is akin to the software process of more than a decade ago. The network process model, proposed here, demonstrates steps that are modeled as a well-de ned process, much like the process notion of software engineering, however, utilizing its own set of processes areas and key practices. In this work, the`quality' of the network engineering process is introduced through the use of a Network Maturity Model NMM, from which an organization's maturity i.e., level of advancement in the design, development and deployment of networks can be evaluated and quanti ed. The objective is similar to the Capability Maturity Model CMM 2 developed by the Software Engineering Institute SEI, which is used world-wide by government and industry to evaluate the level of maturity and quality in the software engineering capabilities of di erent organizations.

No abstract

No abstract

No abstract