Showing papers by "R. V. Prasad published in 2008"

Cognitive functionality in next generation wireless networks: standardization efforts

Abstract: This article discusses recent standardization efforts related to cognitive radio focusing on the work of IEEE Standards Coordinating Committee 41, formerly known as IEEE 1900. Some important tasks to be performed by the CR standardization community also are presented. These tasks will expedite the introduction of CR devices to the market while promoting a fair use of scarce radio resources. Some avenues for using the currently available standards for rapid deployment of CR devices, such as ISO standards, also are discussed.

Address autoconfiguration in wireless ad hoc networks: protocols and techniques

Abstract: With the advent of smaller devices having higher computational capacity and wireless communication capabilities, the world is becoming completely networked. Although, the mobile nature of these devices provides ubiquitous services, it also poses many challenges. In this article, we look in depth at the problem of addressing in wireless ad hoc networks and the currently available techniques and protocols for both IPv4 and IPv6. We present an exhaustive study of the literature and summarize the features of each technique. We believe that this analysis will be helpful for network and application designers, as well as for researchers.

Comparison of Opportunistic Spectrum Multichannel Medium Access Control Protocols

Abstract: This work comprehensively compares four possible multichannel medium access control (MAC) approaches for opportunistic spectrum access (OSA). One of important conclusions to be drawn from the analysis is that multichannel OSA MACs that spread both control and data between all available channels, e.g., hopping MACs, perform best among possible OSA MAC implementations when the PU traffic has long ON/OFF periods compared to the time-scale of the SU channel access.

Solving the Incertitude of Vertical Handovers in Heterogeneous Mobile Wireless Network Using MDP

Abstract: In this paper we introduce and examine via simulations, a Markov decision process (MDP) based approach for vertical handover decision-making. We consider here the case of a heterogeneous network environment where both the legacy WLAN and the novel line-of-sight (LOS)- dependent 60 GHz radio systems are deployed to support indoor high quality multi-media applications. The MDP decision approach takes into account multiple factors such as user preference, network situation, device capability and effects of environment. We show its ability to effectively make handover decision in uncertain situations. The method and results herein are applicable, in general, to any other situation where such a decision is to be made.

Resource Optimization for 60 GHz Indoor Networks Using Dynamic Extended Cell Formation

Abstract: With the advent of opening up 60 GHz Radio with 5 GHz of available spectrum, many bandwidth-hungry applications can be supported. The immediate concern, however, is the constraint on the line-of-sight transmission as well as the short transmission range of signals. As a result, in an indoor network, a mobile user might experience frequent breaks or losses of connection when one moves from one cell to another. To mitigate this problem, the Extended Cell (EC) architecture is proposed. In this paper, a dynamic Extended Cell formation algorithm is proposed based on the actual floor plan and the traffic situation under the network. Moreover, by applying this dynamic EC formation algorithm, we show that the call blocking probability is reduced. The dynamic EC formation also eases the deployment and maintenance cost due to its adaptability to the changing environment.