Request Mechanisms to Reduce the Contention Period in 802.16: A Comparison

Abstract

Nowadays, a large number of applications characterized by stringent end- to-end requirements are on high demand. The development of Broadband Wireless Access (BWA) should enable the ubiquitous and cost-effective deployment of such applications. The IEEE 802.16 standard is currently one of the promising BWA tech- nology under development. The IEEE 802.16 defines the principles of the Physical and Medium Access Control mechanisms to be implemented by the standard. Under the proposed MAC protocol, the Base Station (BS) is responsible of allocating the bandwidth required by the Subscriber Stations (SS). A SS issues its bandwidth re- quest during a pre-defined contention period. Since the user data and signalling data are transmitted over the same band, the design of efficient signalling mechanism aiming to reduce the time and space length of the contention period is nowadays the main focus of a large number of studies. In this paper, we introduce and evaluate two novel bandwidth request mechanisms and compare their performance with the signalling mechanisms proposed by the standard.