標題: | Dynamic bandwidth allocation for multimedia traffic with rate guarantee and fair access in WCDMA systems |
作者: | Chao, CM Tseng, YC Wang, LC 資訊工程學系 電信工程研究所 Department of Computer Science Institute of Communications Engineering |
關鍵字: | mobile computing;OVSF;personal communication services;WCDMA;wireless communication;3G |
公開日期: | 1-九月-2005 |
摘要: | Packet scheduling in a WCDMA system poses a new challenge due to its nature of variable bit rates and location-dependent, time-varying channel conditions. In this work, three new downlink scheduling algorithms for a WCDMA base station are proposed to support multimedia transmissions. Using a credit management and a compensation mechanism, our algorithms provide rate guarantee and fair access to mobile terminals. In particular, we propose to allow a user to simultaneously use multiple OVSF codes in a time-sharing manner, which we call a multicode, shared model. Using multiple codes allows us to compensate those users suffering from bad communication quality or even errors. The proposed schemes can tolerate a multistate link condition (compared to the typically assumed two-state, or good-or-bad, link condition) by adjusting the number of OVSF codes and the spreading factor of each code. Simulation results show that the proposed schemes do achieve higher bandwidth utilization while keeping transmission delay low. |
URI: | http://hdl.handle.net/11536/13313 |
ISSN: | 1536-1233 |
期刊: | IEEE TRANSACTIONS ON MOBILE COMPUTING |
Volume: | 4 |
Issue: | 5 |
起始頁: | 420 |
結束頁: | 429 |
顯示於類別: | 期刊論文 |