单用户OFDM系统中自适应调制和功率分配算法  

Adaptive Modulation and Power Allocation Algorithm for Single-User OFDM Systems

作　　者：王茜[1] 杨连初[1] 

机构地区：[1]湖南中医药大学管理与信息工程学院,湖南长沙410208

出　　处：《电脑与信息技术》2013年第3期19-22,共4页Computer and Information Technology

摘　　要：针对现有最优算法计算复杂度高、不利于实时应用的不足,结合相关自适应比特和功率分配算法的优点,提出了一种新的单用户OFDM系统中联合自适应调制和功率分配算法,在满足给定的总发射功率门限和误码率性能的条件下使系统频谱效率最优。基于分配每比特的功率代价最小原则,找到最优子载波,自适应地将该子载波的调制方式调高一级,高效地进行比特和功率分配。仿真结果表明,新算法的频谱效率性能与最优算法相当,而平均算法复杂度却降低了接近90%,能满足实时性要求较高的业务需求。Optimal adaptive resource allocation algorithms are computationally complex and time consuming, which is unfavorable for real-time application. To overcome these shortcomings and combine with the advantages of the related algorithms, this paper proposes a new adaptive modulation and power allocation algorithm for single-user OFDM systems, which maximizes the spectrum efficiency under the constraint of total transmit power and BER performance. Based on the principle of minimizing the required transmit power per-bit, the proposed algorithm finds the best sub-cartier and allocates bits and power with adaptive modulation which increases one more level from the current one. Simulation results show that the new algorithm has the same performance as the optimal algorithm, and the average computational complexity is decreased by nearly 90%. It can satisfy the higher requirement of the real-time service.

关 键 词：正交频分复用 自适应调制 比特和功率分配 算法复杂度 

分 类 号：TN929.5[电子电信—通信与信息系统]