Abstract EN:

Driven by the growing demand for high-speed broadband services, WiMAX technology has emerged as a competitive alternative to wireline broadband access solution. WiMAX technology, considered in this thesis, offers an IP-based framework that provides high data rates at medium and long range with the ability of supporting fixed, nomadic, portable, and mobile access. Moreover, based on the IEEE 802. 16 standard, the technology provides a set of built-in QoS mechanisms to support heterogeneous classes of traffic including data, voice and video. The 802. 16 standard, however, leaves open the resource management and scheduling mechanisms, which are crucial components to guarantee QoS performance for these services. In this thesis, we evaluate the performance of WiMAX systems in both fixed and highly mobile environments. More particularly, mobile WiMAX is investigated as a V2I communication medium since it is expected to play a major role in ITS. Moreover, after surveying, classifying and comparing different scheduling and admission control mechanisms proposed in this work-in-progress area, we propose two QoS solutions. Both solutions address PMP systems operating in TDD mode. The first solution includes a hierarchical scheduling algorithm that adapts the DL/UL allocations to serve unbalanced traffic. The amounts of these grants are set by the CAC module that adopts a Max-Min fairness approach. The second QoS solution presented in this thesis is a multi-Constraints Scheduling Strategy (mCoSS). In addition to data rate constraints, it supports delay constraints of real-time applications and handles bursty traffics. MCoSS is based on a modified dual-bucket traffic shaping mechanism.