摘要
非线性信道线性化是大容量QAM通信系统关键技术之一。本文从功率器件非线性特性入手,建立了自适应数字基带处理非线性系统模型,对MQAM线性化信道进行计算机模拟,旨在对非线性畸变的MQAM星座点坐标自适应调整。同时讨论了直角价坐标下自适应迭代算法收敛性,分析了非线性信道功率谱。在此基础上尝试将波形形成网络移到校正环路内。发现在理想条件下不影响系统收敛性和校正精度,最后讨论用单片机实现自适应调整的一些问题。
Abstract--The linearization on nonlinear channels is one of key technigues in MQAM high capacity communication systems. In this paper starting with nonlinear chracteristics caused by power devices ,we first bulid up a model of nonlinear systems, that processing on the bassband is adaptive and simulate MQAMchannels linearizated wiht Monte-Carlo method. Then we discuss the convergence about the adaptive alternative algo-rithum in a coordinate and analyze the spectral characteristics on nonlinear channels. Based on the above we try to put the pulse shapping network into the baseband correct loop. Find that it does'nt harm the system convergence and the compenstable presision in theretical condititons. At lats we describe some probiems for the adaptive correction about the MQAMconstellation by the monolithic microcomputer.
