Steady-state analysis of constrained normalized adaptive filters for MAI reduction by energy conservation arguments
Steady-state analysis of constrained normalized adaptive filters for MAI reduction by energy conservation arguments
复制标题
DOI：
10.1016/j.sigpro.2007.07.023
复制
发表时间：
2008-02
期刊：
影响因子：
--
通讯作者：
R. Cavalcante;I. Yamada
中科院分区：
文献类型：
--
作者：
R. Cavalcante;I. Yamada
本文研究了码分多址（CDMA）系统中一种常见的自适应滤波器的稳态性能。研究中的自适应滤波器利用所需用户的幅度的估计，并分为三组不同的归一化因子的选择的最小均方（LMS）算法。从能量守恒关系推导出稳态性能，该能量守恒关系包括对期望用户的幅度的可能错误的估计。分析表明，利用期望用户幅度信息的盲算法可以获得与非盲算法相似的性能。此外，几何考虑揭示的条件下，归一化因子的选择预计有很大的影响算法的收敛性能。数值模拟结果与理论分析吻合较好。
We derive the steady-state performance of a common class of adaptive filters for multiple access interference (MAI) reduction in code division multiple access (CDMA) systems. The adaptive filters under study utilize estimates of the desired user's amplitude and are divided into three groups of least-mean-square (LMS) algorithms differing by the choice of the normalization factor. The steady-state performance is deduced from energy-conservation relations that include a possibly erroneous estimate of the desired user's amplitude. The analyses show that blind algorithms using information about the desired user's amplitude achieve similar performance to that of nonblind algorithms. In addition, geometric considerations reveal the conditions under which the choice of the normalization factor is expected to have great impact on the convergence properties of the algorithms. Numerical simulations show good agreement with theory.