HARQ系统中的功率与速率联合优化方法  

Joint optimization with power and rate control in HARQ system

作　　者：林挺萃[1] 殷锐[1] 张朝阳[1] 

机构地区：[1]浙江大学信息与电子工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2009年第4期651-657,共7页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(60572115);国家"863"高技术研究发展计划资助项目(2007AA01Z257)

摘　　要：研究了混合自动重传(HARQ)发送模式中子包最大重传次数、单次传输功率、子包长度、调制比特数、编码速率等参数与系统频谱效率之间的关系.基于IEEE 802.16e协议,以提高无线传输频谱效率为优化目标,提出HARQ系统接收端带信道参数的反馈模式,给出该模式区别于定参数传输模式功率分配和误包率的约束条件.在加性白色高斯噪声信道下建立模型,分析各参数对总体频谱效率的影响以及各参数相应的优化方法,提出一种次优可实现的迭代算法来自适应控制参数.仿真结果表明,该次优算法可以获得比固定参数的传统算法高的系统性能,使系统频谱效率随信道状况的变好而动态上升.在接收端准确测知信道状况的情况下,以低的算法复杂度取得高的系统传输频谱效率.The relation among maximum retransmission times, power in every transmission, sub-packet length, modulation bits, coding rate in hybrid automatic repeat request （HARQ） transmission mode and the system throughput was studied. A feed-back mode with channel parameters was proposed based on IEEE 802.16e protocol to enhance the throughput of wireless transmission system. The constraint of power allocation and packet error rate in the mode was given, which is different from that in transmission mode with fixed parameters. A model under additive white Gaussian noise channel was established to analyze the influence on the throughput caused by different parameters and the corresponding optimization dependent on certain parameter. A sub-optimal algorithm was proposed to adaptively update parameters. Simulation results show that the algorithm can achieve much higher system performance than the traditional algorithm with constant parameters. The system throughput dynamically increases when channel condition gets bet- ter. The algorithm can get high system throughput with low complexity when channel condition can be precisely detected by the receiver.

关 键 词：IEEE 802.16e 混合自动重传请求 正交频分复用 自适应调制编码 功率和速率联合优化 

分 类 号：TN914.51[电子电信—通信与信息系统]