自适应最优量化查找表预失真算法

为了在不增加查找表（LUT）长度的前提下,进一步改善功率放大器非线性性能,提出1种自适应最优量化LUT的预失真算法.与已有的最优量化LUT算法不同,该算法综合考虑了预失真器特性和输入信号概率分布,理论分析并得到了最优的LUT量化间隔,并给出了全盲条件下的自适应预失真器LUT参数搜索算法.仿真表明：应用该算法的预失真系统的归一化最小均方误差指标优于均匀量化LUT算法和已有的最优量化LUT算法,尤其是在输入信号功率回退较大的情况下,该算法的预失真效果改善更为显著.

Adaptive predistortion algorithm with optimum look-up table spacing

In order to improve the nonlinearity of the power amplifier(PA) without increasing the length of the look-up table(LUT) of the predistorter(PD),an adaptive predistortion algorithm with optimum LUT spacing was put forward.Different from the existing optimum LUT spacing algorithms,basing on the strict mathematics,the algorithm takes care of the nonlinearity of PD and the distribution of the signal,and the optimum LUT quantization spacing was obtained using adaptive algorithm on the blind condition.The simulation results show that the predistortion system with this algorithm has an improved normalized mean squared error performance compared with the uniform LUT spacing algorithm and traditional optimum LUT spacing algorithms and the algorithm exhibits excellent performance especially in the system with input back off(IBO).