无线信道中基于时延约束下的一种调度策略a-电子与信息学报.pdfVIP

第 30 卷第 4 期 电 子 与 信 息 学 报 Vol.30No.4 2008 年 4 月 Journal of Electronics Information Technology Apr. 2008 无线信道中基于时延约束下的一种调度策略 彭烈新①② 朱光喜①② 蔡德钧① ①(华中科技大学电信系 武汉 430074) ②(武汉国家光电实验室 武汉 430074) 摘 要：该文研究无线信道中基于时延约束下功率最小化的调度策略。文章首先将该优化问题转化为非约束 Markov 动态决策过程，随后用动态规划的方法获得了最优解。由于动态规划是基于整个决策阶段而不是在单个阶段做出最 后决策，因而复杂度较高，实时性较差。有鉴于此，该文提出了一种简便策略，该策略只根据当前信道状态和队列 长度做出决策，实时性好，算法简单，而且能使队列具有平稳分布的特征，保证了系统的稳定性。仿真结果显示该 策略的性能接近最优策略。 关键词：资源分配；MDP；时延；Lyapunov 稳定性 中图分类号：TN92 文献标识码：A 文章编号：1009-5896(2008)04-0788-04 A Scheduling Strategy for Wireless Channel under Delay Constraint ①② ①② ① Peng Lie-xin Zhu Guang-xi Cai De-jun ① (Dept. of Electronics Information Eng., Huazhong Univ. of Sci. Tech., Wuhan 430074, China) ② (Wuhan National Laboratory for Optoelectronics, Wuhan 430074, China) Abstract: In this paper, the scheduling strategy of minimizing power under delay constraint is proposed in wireless channel. The problem is first formulated as an unconstrained Markov Decision Process （MDP）and solved by dynamic programming. But its final decision which is made over all processes instead of individual one make it with high convexity and bad real time property. So a simple strategy which is based on the current channel state and queue length is given for its good real time property and simple arithmetic. And by this strategy the steady-state distribution of the queue exists, which makes the queue stable. Finally, the simulation results show the performance of the simple strategy is approximate to the optimal one