一种降低FBMC-OQAM系统PAPR的低复杂度选择性映射算法

滤波器组多载波(FBMC)是第五代蜂窝网络无线接入技术重点考虑的对象之一,然而其存在较高的峰均功率比(PAPR).通过分析FBMC-OQAM信号的重叠特性和信号功率分布特点,将传统选择性映射(SLM)方法加以改进,提出了一种比色散选择性映射(DSLM)方法更优的低复杂度色散选择性映射(LD-SLM)方法.LD-SLM方法用备选旋转矢量将当前数据块信号旋转,通过计算在当前信号周期T,3T]区间内信号的PAPR来选取最优旋转矢量,并更新当前数据块信号,接着对下一个数据块信号进行同样的优化,直至所有的数据块都被优化.通过比较算法复杂度可知,LD-SLM算法相比DSLM算法降低了50％,仿真实验表明LD-SLM方法能有效降低FBMC-OQAM系统的PAPR.

A low-complexity selective mapping algorithm for PAPR reduction in FBMC-OQAM systems

Filter-bank multi-carrier( FBMC) is one of the key objects of the fifth generation cellular net-work(5G) radio access technology. However,there is also a high peak-to-average power ratio(PAPR). Through analyzing the overlapping characteristics and signal power distribution characteristics of FBMC-OQAM signal,the selective mapping( SLM) method of reducing PAPR in OFDM system is improved,and a Low-complexity Dispersion Selective Mapping(LD-SLM) method is proposed,which is better than the Dispersive Selective Mapping( DSLM) method. The LD-SLM method rotates the current data block signal with the alternative rotation vector,and selects the optimal rotation vector by calculating the PAPR of the signal in the current signal period T,3T],and updates the current data block signal. The data block sig-nals are similarly optimized until all data blocks are optimized. By comparing the algorithm complexity,it is concluded that the LD-SLM algorithm is 50％ lower than the DSLM algorithm. The simulation results show that the LD-SLM method can effectively reduce the PAPR of the FBMC-OQAM system.