The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorit...The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorithm.The command input was corrected by weights to generate the desired input for the algorithm,and the feedback was brought into the feedback correction,whose output was the weighted feedback.The weights of the normalized LMS adaptive filtering algorithm were updated on-line according to the estimation error between the desired input and the weighted feedback.Thus,the updated weights were copied to the input correction.The estimation error was forced to zero by the normalized LMS adaptive filtering algorithm such that the weighted feedback was equal to the desired input,making the feedback track the command.The above concept was used as a basis for the development of amplitude phase control.The method has good real-time performance without estimating the system model.The simulation and experiment results show that the proposed amplitude phase control can efficiently cancel the amplitude attenuation and phase delay with high precision.展开更多
在对变步长归一化最小均方误差(Variable step size normalized least mean square,VSS-NLMS)的几种算法以及各个算法在远端和双端通话模式下的性能分析比较的基础上,对NEW-NPVSS(NEW non-parametricVSS)算法进行了改进。在双端通话的...在对变步长归一化最小均方误差(Variable step size normalized least mean square,VSS-NLMS)的几种算法以及各个算法在远端和双端通话模式下的性能分析比较的基础上,对NEW-NPVSS(NEW non-parametricVSS)算法进行了改进。在双端通话的情况下改进算法具有更好的收敛性;然后提出了基于滤波器系数梯度的变步长新算法,当滤波器系数梯度小于门限值时,采用固定步长更新滤波器系数。反之,则停止更新滤波器系数,并且用远端模式下的系数替代当前系数。仿真结果表明所提出的算法在远端通话模式下比其他VSS-NLMS算法具有更好的收敛性,在双端情况下具有比固定步长NLMS(Normalized least mean square)和SVSS(Simple VSS)更好的收敛性。展开更多
智能反射面(Reconfigurable Intelligent Surface,RIS)有着操纵性强、能耗低、方便部署等优势,已成为6G(第六代移动通信)的关键技术。研究了关于智能反射面的信道估计算法,对于传统算法在传播时路径会因角度原因发生偏移的情况,采用了Tu...智能反射面(Reconfigurable Intelligent Surface,RIS)有着操纵性强、能耗低、方便部署等优势,已成为6G(第六代移动通信)的关键技术。研究了关于智能反射面的信道估计算法,对于传统算法在传播时路径会因角度原因发生偏移的情况,采用了Tucker分解的稀疏角度域高阶奇异值分解(High Order Singular Value Decomposition,HOSVD)信道估计算法来解决路径偏移的问题。为了验证所提出算法的鲁棒性,对比了传统的交替最小二乘法信道估计算法,可以得到不管是在用户数量、传播的路径偏移上都能取得比传统的信道估计算法更好的归一化最小均方误差(Normalized Mean Squared Error,NMSE)效果。展开更多
A new normalized least mean square(NLMS) adaptive filter is first derived from a cost function, which incorporates the conventional one of the NLMS with a minimum-disturbance(MD)constraint. A variable regularization f...A new normalized least mean square(NLMS) adaptive filter is first derived from a cost function, which incorporates the conventional one of the NLMS with a minimum-disturbance(MD)constraint. A variable regularization factor(RF) is then employed to control the contribution made by the MD constraint in the cost function. Analysis results show that the RF can be taken as a combination of the step size and regularization parameter in the conventional NLMS. This implies that these parameters can be jointly controlled by simply tuning the RF as the proposed algorithm does. It also demonstrates that the RF can accelerate the convergence rate of the proposed algorithm and its optimal value can be obtained by minimizing the squared noise-free posteriori error. A method for automatically determining the value of the RF is also presented, which is free of any prior knowledge of the noise. While simulation results verify the analytical ones, it is also illustrated that the performance of the proposed algorithm is superior to the state-of-art ones in both the steady-state misalignment and the convergence rate. A novel algorithm is proposed to solve some problems. Simulation results show the effectiveness of the proposed algorithm.展开更多
基金Project(50905037) supported by the National Natural Science Foundation of ChinaProject(20092304120014) supported by Specialized Research Fund for the Doctoral Program of Higher Education of China+2 种基金 Project(20100471021) supported by the China Postdoctoral Science Foundation Project(LBH-Q09134) supported by Heilongjiang Postdoctoral Science-Research Foundation,China Project (HEUFT09013) supported by the Foundation of Harbin Engineering University,China
文摘The electro-hydraulic servo system was studied to cancel the amplitude attenuation and phase delay of its sinusoidal response,by developing a network using normalized least-mean-square (LMS) adaptive filtering algorithm.The command input was corrected by weights to generate the desired input for the algorithm,and the feedback was brought into the feedback correction,whose output was the weighted feedback.The weights of the normalized LMS adaptive filtering algorithm were updated on-line according to the estimation error between the desired input and the weighted feedback.Thus,the updated weights were copied to the input correction.The estimation error was forced to zero by the normalized LMS adaptive filtering algorithm such that the weighted feedback was equal to the desired input,making the feedback track the command.The above concept was used as a basis for the development of amplitude phase control.The method has good real-time performance without estimating the system model.The simulation and experiment results show that the proposed amplitude phase control can efficiently cancel the amplitude attenuation and phase delay with high precision.
文摘在对变步长归一化最小均方误差(Variable step size normalized least mean square,VSS-NLMS)的几种算法以及各个算法在远端和双端通话模式下的性能分析比较的基础上,对NEW-NPVSS(NEW non-parametricVSS)算法进行了改进。在双端通话的情况下改进算法具有更好的收敛性;然后提出了基于滤波器系数梯度的变步长新算法,当滤波器系数梯度小于门限值时,采用固定步长更新滤波器系数。反之,则停止更新滤波器系数,并且用远端模式下的系数替代当前系数。仿真结果表明所提出的算法在远端通话模式下比其他VSS-NLMS算法具有更好的收敛性,在双端情况下具有比固定步长NLMS(Normalized least mean square)和SVSS(Simple VSS)更好的收敛性。
文摘智能反射面(Reconfigurable Intelligent Surface,RIS)有着操纵性强、能耗低、方便部署等优势,已成为6G(第六代移动通信)的关键技术。研究了关于智能反射面的信道估计算法,对于传统算法在传播时路径会因角度原因发生偏移的情况,采用了Tucker分解的稀疏角度域高阶奇异值分解(High Order Singular Value Decomposition,HOSVD)信道估计算法来解决路径偏移的问题。为了验证所提出算法的鲁棒性,对比了传统的交替最小二乘法信道估计算法,可以得到不管是在用户数量、传播的路径偏移上都能取得比传统的信道估计算法更好的归一化最小均方误差(Normalized Mean Squared Error,NMSE)效果。
基金supported by the National Natural Science Foundation of China(61571131 11604055)
文摘A new normalized least mean square(NLMS) adaptive filter is first derived from a cost function, which incorporates the conventional one of the NLMS with a minimum-disturbance(MD)constraint. A variable regularization factor(RF) is then employed to control the contribution made by the MD constraint in the cost function. Analysis results show that the RF can be taken as a combination of the step size and regularization parameter in the conventional NLMS. This implies that these parameters can be jointly controlled by simply tuning the RF as the proposed algorithm does. It also demonstrates that the RF can accelerate the convergence rate of the proposed algorithm and its optimal value can be obtained by minimizing the squared noise-free posteriori error. A method for automatically determining the value of the RF is also presented, which is free of any prior knowledge of the noise. While simulation results verify the analytical ones, it is also illustrated that the performance of the proposed algorithm is superior to the state-of-art ones in both the steady-state misalignment and the convergence rate. A novel algorithm is proposed to solve some problems. Simulation results show the effectiveness of the proposed algorithm.