摘要
针对卫星通信系统记忆功率放大器引起的非线性失真,提出了一种单路计算方法与QRD-LS算法相结合的新型预失真方法。该方法基于记忆多项式模型与间接学习结构,采用基带I、Q信号中的一路作为最小二乘算法的输出,同时预失真训练器输入矩阵由复数转化为实数;基于Givens变换的QR分解避免了最小二乘算法直接对矩阵求逆。针对16QAM调制信号与AB类功放模型进行仿真,结果表明:系统EVM从6.2%提升到0.8%,带外功率谱抑制20 d B。
For satellite communications systems, this paper presents a new method for predistortionthat combine single path calculation algorithm and QRD-LS.The method is based memory polynomial model and indirect learning structure, using one route of the input signals （I or Q）astheoutput of least squares algorithm, while predistortion trainer input matrix by a complex into a real number; Based on Givens QR decomposition to avoid the least-squares algorithm for matrix inversion directly.Simulation based on the 16QAM modulation signal and Class AB modelshows that system EVM decreased from 6.2% to 0.8% and 20dB out-bandsuppression.
出处
《电子设计工程》
2017年第9期171-174,共4页
Electronic Design Engineering
关键词
卫星通信
单路计算
QRD—LS
数字预失真
satellite communication
single path calculation
QRD-LS
digital predistortion
