標題: Impacts of radio channel characteristics, heterogeneous traffic intensity, and near-far effect on rate adaptive scheduling algorithms
作者: Chen, Chiung-Jang
Wang, Li-Chun
交大名義發表
National Chiao Tung University
關鍵字: heterogeneous traffic intensity;rate adaptive scheduling;near-far effect
公開日期: 1-九月-2006
摘要: Applying adaptive modulation combined with scheduling in a shared data channel can substantially improve the spectral efficiency for wireless systems. This performance gain results from the multiuser diversity, which exploited independent channel variations across multiple users. In this paper, we present a cross-layer analysis to integrate physical-layer channel characteristics, media access control (MAC) layer scheduling strategies, and the network layer issue of heterogeneous traffic intensity across near-far users. Specifically, for radio channel characteristics, we take account of path loss, slowly varying log-normal shadowing and fast-varying Nakagami fading. We also evaluate the impact of selective transmit diversity on the throughput and fairness of wireless data networks. Furthermore, we consider three MAC schedulers: random scheduler, greedy scheduler (GS), and a newly proposed queue-length-based scheduler (QS). By applying the proposed cross-layer analytical framework, the following insights can be gained. First, for the three considered schedulers, channel fluctuations induced by Nakagami fading or log-normal shadowing can improve both total throughput and fairness. Second, using selective transmit diversity can improve throughput, but is unfavorable for the fairness performance. Third, the GS and the QS methods can improve throughput at the expense of unfairness to the far users. However, the throughput improvement from using the GS and the QS decreases as the traffic intensity of the far user increases. In summary, this cross-layer analysis can be used to develop new scheduling mechanisms for achieving better tradeoff between the fairness and throughput for wireless data networks.
URI: http://dx.doi.org/10.1109/TVT.2006.877709
http://hdl.handle.net/11536/11811
ISSN: 0018-9545
DOI: 10.1109/TVT.2006.877709
期刊: IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
Volume: 55
Issue: 5
起始頁: 1544
結束頁: 1554
顯示於類別:期刊論文


文件中的檔案:

  1. 000240757200010.pdf