摘要
误差矢量幅度(EVM,Error Vector Magnitude)是用于衡量调制器性能好坏的一个关键参数。在传输过程中,由于信号受到噪声等因素的影响,会造成EVM测量值不准的问题。分析EVM的测量结果在调制器性能的测试和优化过程中起到十分关键的作用,于是准确的补偿信号从而得到有效地EVM测量结果尤为重要。本文通过分析通信系统的信号模型,结合最大似然算法以及基于传输函数特性的频偏估计算法提出一种效率更高、更准确,并能很好地适用于TDD和FDD两种帧结构的频偏估计改进算法。仿真结果表明,本算法的测量结果较为准确,具有实际应用意义。
EVM（ Error Vector Magnitude） is a key parameter to measure the modulator performance. In the process of transmission,the signal could be affected by many factors including noise,and this may result in the inaccuracy of EVM measuring value. Analysis on EVM measuring result plays a crucial role in modulator performance test and optimization,thus to precisly compensate the signal and achieve effictive EVM measuring results is of utmost significance. Hence,by analyzing the signal model of communication system and combining the maximum likelihood algorithm with frequency-offset estimation algorithm based on transmission function characteristics,a modofied frequenty-offset estimation algorithm with better efficiency and accuracy,and better applicability to TDD and FDD frame structure is proposed. Simulation results show that this proposed algorithm enjoys the priorities of accurate measurement and practical application significance.
出处
《通信技术》
2014年第11期1291-1299,共9页
Communications Technology
基金
上海市科研计划项目(No.14ZR1442700)~~
