针对卫星信号接收中干扰信号功率远大于有用信号功率的问题,根据功率倒置阵列原理,尝试使用递归最小二乘方(Recursive Least Square,RLS)算法和最小均方(Least Mean Square,LMS)算法来求功率倒置阵的最优权值,并对不同阵元数目和不同干...针对卫星信号接收中干扰信号功率远大于有用信号功率的问题,根据功率倒置阵列原理,尝试使用递归最小二乘方(Recursive Least Square,RLS)算法和最小均方(Least Mean Square,LMS)算法来求功率倒置阵的最优权值,并对不同阵元数目和不同干扰功率条件下这两种算法从功率倒置阵列性能方面进行比较和评估,以探讨各自的优点和不足。实验结果表明,基于RLS和LMS的功率倒置阵列算法均可使天线阵列在干扰来向上自动生成零陷,零陷的深度随阵元数目和干扰功率的增加而加深。展开更多
针对目前地震工程研究领域在滤波方法上存在人为因素、峰值突刺、噪声干扰等方面的缺陷,结合递归最小二乘法(RLS)和循环神经网络(RNN)模型,提出了一种自适应滤波的新方法。研究分析表明,该方法通过设置自适应调节滤波器参数以及算法的...针对目前地震工程研究领域在滤波方法上存在人为因素、峰值突刺、噪声干扰等方面的缺陷,结合递归最小二乘法(RLS)和循环神经网络(RNN)模型,提出了一种自适应滤波的新方法。研究分析表明,该方法通过设置自适应调节滤波器参数以及算法的自我迭代等方式进行滤波,对噪声识别能力和滤波速度上均优于美国地质调查局(United States Geological Survey,USGS)所推荐的传统滤波方法,并可有效降低滤波后对原始波形的失真损坏以及相位提前等问题。同时,运用所提自适应滤波方法将其应用于不同场地类型台站的含速度脉冲近场地震记录,进一步验证了自适应滤波方法的有效性和适用性。研究成果为地震工程领域的滤波分析提出了一种新思路和新方法,也可为地震记录处理及相关应用工作提供参考。展开更多
A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,...A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,or environmental changes.Since PLS decomposition structure enables multi-loop controller design within latent spaces,a multivariable adaptive control scheme can be converted easily into several independent univariable control loops in the PLS space.In each latent subspace,once the model error exceeds a specific threshold,online adaptation rules are implemented separately to correct the plant model mismatch via a recursive least squares (RLS) algorithm.Because the IMC extracts the inverse of the minimum part of the internal model as its structure,the IMC controller is self-tuned by explicitly updating the parameters,which are parts of the internal model.Both parameter convergence and system stability are briefly analyzed,and proved to be effective.Finally,the proposed control scheme is tested and evaluated using a widely-used benchmark of a multi-input multi-output (MIMO) system with pure delay.展开更多
文摘针对卫星信号接收中干扰信号功率远大于有用信号功率的问题,根据功率倒置阵列原理,尝试使用递归最小二乘方(Recursive Least Square,RLS)算法和最小均方(Least Mean Square,LMS)算法来求功率倒置阵的最优权值,并对不同阵元数目和不同干扰功率条件下这两种算法从功率倒置阵列性能方面进行比较和评估,以探讨各自的优点和不足。实验结果表明,基于RLS和LMS的功率倒置阵列算法均可使天线阵列在干扰来向上自动生成零陷,零陷的深度随阵元数目和干扰功率的增加而加深。
文摘针对目前地震工程研究领域在滤波方法上存在人为因素、峰值突刺、噪声干扰等方面的缺陷,结合递归最小二乘法(RLS)和循环神经网络(RNN)模型,提出了一种自适应滤波的新方法。研究分析表明,该方法通过设置自适应调节滤波器参数以及算法的自我迭代等方式进行滤波,对噪声识别能力和滤波速度上均优于美国地质调查局(United States Geological Survey,USGS)所推荐的传统滤波方法,并可有效降低滤波后对原始波形的失真损坏以及相位提前等问题。同时,运用所提自适应滤波方法将其应用于不同场地类型台站的含速度脉冲近场地震记录,进一步验证了自适应滤波方法的有效性和适用性。研究成果为地震工程领域的滤波分析提出了一种新思路和新方法,也可为地震记录处理及相关应用工作提供参考。
基金Project supported by the National Natural Science Foundation of China (No.60574047)the National High-Tech R & D Program (863)of China (No.2007AA04Z168)the Research Fund for the Doctoral Program of Higher Education of China (No.20050335018)
文摘A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,or environmental changes.Since PLS decomposition structure enables multi-loop controller design within latent spaces,a multivariable adaptive control scheme can be converted easily into several independent univariable control loops in the PLS space.In each latent subspace,once the model error exceeds a specific threshold,online adaptation rules are implemented separately to correct the plant model mismatch via a recursive least squares (RLS) algorithm.Because the IMC extracts the inverse of the minimum part of the internal model as its structure,the IMC controller is self-tuned by explicitly updating the parameters,which are parts of the internal model.Both parameter convergence and system stability are briefly analyzed,and proved to be effective.Finally,the proposed control scheme is tested and evaluated using a widely-used benchmark of a multi-input multi-output (MIMO) system with pure delay.
