通用滤波多载波系统的改进部分传输序列算法

Improved partial transmission sequence algorithm for universal filtered multi-carrier system

针对通用滤波多载波(UFMC)系统峰均功率比(PAPR)高的问题,提出一种基于固定功率门限的多级寻优部分传输序列(PTS)算法.采用功率门限,可减少传统PTS方法寻优过程中峰值功率的时域样本信号数量,从而降低传统PTS方法寻优的计算量.采用多级寻优PTS方法,可解决传统PTS方法计算量随相位集合元素的个数增加呈指数增长的问题.提出结合多级寻优和功率门限的PTS方法以进一步降低传统PTS方法的计算复杂度,各级的门限可采用同一固定门限,进一步简化基于功率门限的多级寻优PTS方法的判决结构.仿真结果表明:UFMC系统采用所提出的基于固定功率门限的多级PTS算法不仅可保证UFMC系统抑制高PAPR的性能,而且显著降低了计算复杂度,还可推广应用于正交频分复用(OFDM)系统.

Aiming at the problem of high peak-to-average power ratio(PAPR) for universal filtered multi-carrier(UFMC) system,a multi-level optimization partial transmission sequence(PTS) algorithm based on fixed power threshold was proposed.The number of sample signals in time domain could be reduced in the process of peak power optimization by applying the power threshold in the traditional PTS method,and the computation complexity was also reduced consequently.The problem that the computation complexity increased exponentially with the element number of phase set in the traditional PTS method could be solved with the multi-level optimization PTS method.To further reduce the computation complexity,it was proposed to combine the multi-level optimization and power threshold in the traditional PTS method.The same fixed threshold could be applied in the multi-level PTS method,which could further simplify the decision structure of multi-level optimization PTS.Simulation results show that the proposed multi-level PTS algorithm based on fixed power threshold not only can guarantee the performance of UFMC system to suppress high PAPR,but also significantly reduce the computational complexity,and can be applied to orthogonal frequency division multiplexing(OFDM)systems.