tailieunhanh - Báo cáo hóa học: "Adaptive QoS provision for IEEE 802.16e BWA networks based on cross-layer design"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Adaptive QoS provision for IEEE BWA networks based on cross-layer design | Zhang et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 69 EURASIP Journal on . http content 20ii i 69 Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Adaptive QoS provision for IEEE BWA networks based on cross-layer design Hongtao Zhang1 Xiaoxiang Wang1 ZB Qin1 GS Kuo2 and Thomas Michael Bohnert3 Abstract This article proposes an integrated framework for adaptive QoS provision in IEEE broadband wireless access networks based on cross-layer design. On one hand an efficient admission control AC algorithm is proposed along with a semi-reservation scheme to guarantee the connection-level QoS. First to guarantee the service continuity for handoff connections and resource efficiency our semi-reservation scheme considers both users handoff probability and average resource consumption together which effectively avoids resource overreservation and insufficient reservation. For AC a new handoff connection is accepted only when the target cell has enough resource to afford both instantaneous and average resource consumption to meet the average source rate request. On the other hand a joint resource allocation and packet scheduling scheme is designed to provide packet-level QoS guarantee in term of QoS rate which can ensure fairness for the services with identical priority level in case of bandwidth shortage. Particularly an enhanced bandwidth request scheme is designed to reduce unnecessary BR delay and redundant signaling overhead caused by the existing one in IEEE which further improves the packet-level QoS performance and resource efficiency for uplink transmission. Simulation results show that the proposed approach not only balances the tradeoff among connection blocking rate connection dropping rate and connection failure rate but also achieves low mean packet dropping rate PDR small deviation of PDR and low QoS outage rate. Moreover high resource efficiency is .