摘要
针对同时同频全双工系统中射频域干扰对消收敛速度与对消比相互制约的问题,提出基于时变步长最小均方算法的射频自干扰对消方法.该方法在正交两路合成干扰对消方案基础上,利用Logistic函数非线性关系实时改变步长因子,在最小均方准则下实现两路衰减器的快速精确调整,完成自干扰信号的有效对消.最后,理论分析了该对消方法的收敛性和稳态失调误差,给出了收敛状态下能够获得对消比的闭合表达式.理论分析和仿真表明,该方法的收敛时间缩短为已有变步长对消方法的1/4,最终达到的对消比与已有方法相比提高了约5dB.
A new cancellation method based on time-varying step-size least mean square algorithm is proposed to compromise the convergence speed and cancellation ratio of radio frequency (RF) cancellation methods for co-frequency and co-time full duplex (CCFD) in this paper. This method is constructed on cancellation scheme with a composite of in-phase and quadrature signals, and the nonlinear characteristic of logistic function is utilized to vary step-size. Then the two attenuators are accurately fine-tuned by varying step-size and least mean square criterion to cancel the self-interference. Finally, we analyze the convergence and misadjustment steady-state error of this interference cancellation method in theory, and extract the closed expression of convergent cancellation ratio. Theory analysis and simulations verify that convergence time of proposed method is only a quarter of existing methods and lasted cancellation ratio is more 5 dB than existing methods. Copyright © 2015 by Editorial Department of Chinese Journal of Radio Science
出处
《电波科学学报》
EI
CSCD
北大核心
2015年第6期1069-1077,共9页
Chinese Journal of Radio Science
基金
国家自然科学基金(U1035002/L05
61001087
61101034
61271164)
国家科技重大专项(2014ZX03003001-002
2012ZX03003010-003
2011ZX03001-006-01)
中国移动通信有限公司研究院合作项目
