A Cross-Layer Approach in Sensing and Resource Allocation for Multimedia Transmission over Cognitive UWB Networks

Norazizah Mohd Aripin,A C C Lo,S H S Ariffin,S K S Yusof,Rozeha A Rashid,N Fisal

doi:10.1155/2010/467813

Abstract

We propose an MAC centric cross-layer approach to address the problem of multimedia transmission over cognitive Ultra Wideband (C-UWB) networks. Several fundamental design issues, which are related to application (APP), medium access control (MAC), and physical (PHY) layer, are discussed. Although substantial research has been carried out in the PHY layer perspective of cognitive radio system, this paper attempts to extend the existing research paradigm to MAC and APP layers, which can be considered as premature at this time. This paper proposed a cross-layer design that is aware of (a) UWB wireless channel conditions, (b) time slot allocations at the MAC layer, and (c) MPEG-4 video at the APP layer. Two cooperative sensing mechanisms, namely, AND and OR, are analyzed in terms of probability of detection ( ), probability of false alarm ( ), and the required sensing period. Then, the impact of sensing scheduling to the MPEG-4 video transmission over wireless cognitive UWB networks is observed. In addition, we also proposed the packet reception rate- (PRR-) based resource allocation scheme that is aware of the channel condition, target PRR, and queue status.

Highlights

Limited available spectrum and inefficient utilization of spectrum necessitate the use of Cognitive Radio (CR) approach to exploit the existing wireless spectrum opportunistically
We propose an medium access control (MAC) centric cross-layer approach to address the problem of multimedia transmission over cognitive Ultra Wideband (C-Ultra wideband (UWB)) networks
By considering the findings in the preliminary investigation, Signal-to-Noise ratio (SNR) is considered as the main Quality of Service (QoS) metric at the PHY layer to determine the appropriate sensing time for cognitive users in our cross layer design

Summary

Introduction

Limited available spectrum and inefficient utilization of spectrum necessitate the use of Cognitive Radio (CR) approach to exploit the existing wireless spectrum opportunistically. In CR networks, primary users (PUs) shall be protected while secondary or cognitive users (CUs) access the spectrum either in an overlay or an underlay mode It is the responsibility of a CU to ensure that its existence is not felt by the PU. This paper proposes a novel MAC centric cross-layer design that is aware of the dynamic time-varying UWB wireless channel at the PHY layer and the target Quality of Service (QoS) for multimedia delivery, providing optimal sensing scheduling and adaptive resource allocation. We consider the MAC centric cross layer design which is aware of MPEG-4 QoS requirements and PHY channel conditions.

Related Works

Proposed Cross Layer Design

Results and Analysis

Conclusion