LTE-Advanced系统中的自适应调制技术

摘要

自适应调制技术是LTE-Advanced系统自适应调制编码(AMC)技术的一项重要研究内容.根据均方误差函数的下凸性,在不同信道模型下,通过迭代算法校正得到新型MCS等级(包含256QAM高阶调制)的通用β值,并与传统MCS等级进行性能对比.仿真结果显示,新型MCS等级在高信噪比时提供的系统吞吐量更高,且优化后的β值使CQI估计更准确.%Adaptive modulation technology is an important research content of AMC technology in LTE-Advanced system.The β value of new MCS levels were studied,in which the higher order modulation 256QAM was used,then the general β value of new MCS levels by the iterative algorithm in several different channel models were obtained,according to the convexity of the mean square error function,and compared with the traditional MCS levels.The simulation results show that the new MCS levels provide higher system performance when SNR is high,and the optimized β value makes CQI calculation more accurately.