改进的OFDM系统自适应资源分配算法  

Improved Adaptive Resource Allocation Algorithm for OFDM Systems

作　　者：赵博[1] 李莉[1] 胡成洋[1] 胡贵军[1] 

机构地区：[1]吉林大学通信工程学院,长春130012

出　　处：《吉林大学学报（信息科学版）》2014年第2期113-118,共6页Journal of Jilin University（Information Science Edition）

基　　金：国家自然科学基金资助项目(61177066)

摘　　要：在自适应正交频分复用(OFDM:Orthogonal Frequency Division Multiplexing)系统中,传统迭代注水功率分配(IWFP:Iterative Water-Filling Power)算法对星座规模量化程度要求过高,实际应用性不强。为此,在发射总功率和系统误码率上限恒定的条件下,提出了一种基于IWFP算法的改进算法。该算法在IWFP算法基础上进行了比特和功率分配的二次调整,算法更加符合系统调制的星座规模和实际发射需求。仿真结果表明,在误比特率(BER:Bit Error Rate)为10-4时,改进算法对信噪比的要求比IWFP算法高约3 dB,比未经自适应调制的OFDM系统功率比特分配算法即等功率分配算法(EPA:Equalization Power Algorithm)低8 dB,接近于系统的最优性能,且运算复杂度不高。An efficient power and bit allocation algorithm based on IWFP （Iterative Water-Filling Power） algorithm is proposed for the adaptive OFDM （Orthogonal Frequency Division Multiplexing） systems.The traditional iterative water-filling power allocation algorithm needs high scale of constellation quantitative and does not fit for the practical applications.The proposed algorithm has a bit and power allocation of secondary adjustment,which conforms to the size of modulation constellation and the actual emission requirements.The simulation results show that with the same BER（Bit Error Rate）of 10-4 the required SNR （Signal-to-Noise Ratio） in proposed algorithm is higher than IWFP algorithm nearly 3 dB.The proposed algorithm is lower than that in the traditional distribution algorithm by nearly 8 dB.The proposed algorithm is close to the optimal performance of the system with the low complexity of computing.

关 键 词：自适应OFDM IWFP算法 比特和功率分配 

分 类 号：TN92[电子电信—通信与信息系统]