东南大学学报（英文版）2020，Vol.36Issue(2)：145-151,7.DOI:10.3969/j.issn.1003-7985.2020.02.004
新型变步长LMS方法及OFDMA信号DOA估计中的应用
A new variable step-size LMS method and its application in DOA estimation of OFDMA signals
摘要
Abstract
To meet the requirements of quick positioning of mobile terminals from base stations (BSs) or third-party devices,as well as to improve the convergence speed and reduce the steady state maladjustment of the least mean square (LMS) method,a new logarithmic-sigmoid variable step-size LMS (LG-SVSLMS) was proposed and applied to estimate the direction of arrival (DOA) of orthogonal frequency division multiple access (OFDMA) signals.Based on the proposed LG-SVSLMS,a non-blind DOA estimation system for OFDMA signals was constructed.The proposed LGSVSLMS adopts a new multi-parameter step-size update function which combines the sigmoid function and the logarithmic function.It controls the adjustment magnitude of step-size during the initial and steady state phases of the LMS method to achieve both a high convergence speed and low steady state maladjustment.Finally,simulation was conducted to verify the performance of the LG-SVSLMS.The simulation results show that the non-blind DOA estimation system based on the LG-SVSLMS can accurately estimate the DOA of the target signal in the scenario where interference signals from multi-source and multi-path fading signals arrive at the thirdparty devices asynchronously with the target signal,and the estimation deviation is within ± 3°.The non-blind DOA estimation for OFDMA signals with the proposed LGSVSLMS is of great significance for the instant positioning technology of mobile terminals based on the adaptive antenna array.关键词
波达方向/可变步长LMS/正交频分复用多址/第三方设备Key words
direction of arrival/variable step-size least mean square/orthogonal frequency division multiple access/third-party devices分类
信息技术与安全科学引用本文复制引用
赵砚,林利,董文,王灏,吴镇滔,王霄峻,陈晓曙..新型变步长LMS方法及OFDMA信号DOA估计中的应用[J].东南大学学报（英文版）,2020,36(2):145-151,7.基金项目
The Social Development Projects of Jiangsu Science and Technology Department (No.BE2018704),the Technological Innovation Projects of Ministry of Public Security of China (No.20170001). （No.BE2018704）
