固态功率放大器数字预失真记忆效应补偿技术研究及实现-测试计量技术及仪器专业论文.docxVIP

摘要 摘要 万方数据 万方数据 摘 要 功率放大器是现代无线通信系统中非线性较强的器件，其性能的优劣直接影 响通信质量的好坏。目前大多数的功放线性化技术都局限于功率放大器模型是无 记忆的，但随着宽带信号的应用，功率放大器的记忆效应愈加显著，以致传统的 线性化技术补偿功放非线性效果并不理想。因此，考虑功放记忆效应的线性化技 术已成为当前国内外研究的热点。 本文对固态功率放大器数字预失真记忆效应补偿技术进行了系统的研究。首 先，阐述功率放大器的非线性特性及其常见的无记忆模型，进而深入分析功率放 大器的记忆效应原理及有记忆模型，并综合比较目前主流的线性化技术，在数字 预失真技术的基础上提出基于补偿功放记忆效应的系统设计方案。 其次，根据提出的系统设计方案，对其中所涉及的关键算法进行重点研究， 具体包括：窄带训练序列对查找表的实时更新；环路时延的估计；横向滤波器抽 头系数的自适应更新。使用 Matlab/Simulink 工具对数字基带系统建模，最终的仿 真结果显示：以查找表和自适应滤波器为核心的补偿功放记忆效应的系统方案能 够使得经过功放后的宽带信号 ACPR 改善达到约 25dB。 最后，在 FPGA+DSP 的硬件架构上实现所提出的方案。双音和宽带信号的测 试结果表明：双音信号的三阶交调可改善约 20dB，宽带信号的 ACPR 可改善约 16dB，有效地补偿了功率放大器的记忆效应，达到了预期目标。 关键词：数字预失真，记忆效应，功率放大器，查找表，Simulink I ABSTRACT ABSTRACT ABSTRACT ABSTRACT 万方数据 万方数据 万方数据 万方数据 ABSTRACT Power amplifier is the strongly nonlinear component of modern wireless communication systems, its performance will directly affect the communication quality. At present, most linearization techniques of power amplifier are limited to the memoryless model, but with the application of the broadband signal, memory effect of power amplifier will become more significant, so that the traditional linearization techniques compensating for memory effect are no more satisfying. In order to improve the linearity of broadband power amplifier, the linearization technology considering memory effect of power amplifier has become a hot trend at home and abroad in recent years. This dissertation studies digital pre-distortion techniques compensating for memory effect of solid state power amplifier systematically. Firstly, it focuses on the nonlinear characteristics and the common memoryless model of power amplifier; then it analyses the memory effect principle and the memory model of power amplifier; then it compares comprehensively the current mainstream linearization techniques and proposes the system design scheme about how to compensate for power amplifier’s memory effect based on digital pre-distortion technology. Secondly, according to the proposed system design scheme, this diss