The problem of discrete-time model identification of industrial processes with time delay was investigated.An iterative and separable method is proposed to solve this problem,that is,the rational transfer function mod...The problem of discrete-time model identification of industrial processes with time delay was investigated.An iterative and separable method is proposed to solve this problem,that is,the rational transfer function model parameters and time delay are alternately fixed to estimate each other.The instrumental variable technique is applied to guarantee consistent estimation against measurement noise.A noteworthy merit of the proposed method is that it can handle fractional time delay estimation,compared to existing methods commonly assuming that the time delay is an integer multiple of the sampling interval.The identifiability analysis for time delay is addressed and correspondingly,some guidelines are provided for practical implementation of the proposed method.Numerical and experimental examples are presented to illustrate the effectiveness of the proposed method.展开更多
This paper addresses the problem of channel estimation for broadband MIMO-OFDM systems. An improved channel estimator with multipath time delay detection and channel gain estimation is proposed. In the algorithm, we u...This paper addresses the problem of channel estimation for broadband MIMO-OFDM systems. An improved channel estimator with multipath time delay detection and channel gain estimation is proposed. In the algorithm, we used the correlation of the channel taps and a well-designed adjustment scheme to increase the accuracy of the time delay detection. The most attractive advantage is that the complicated matrix calculation is replaced by search steps which can acquire the channel order and estimate the channel parameters without significantly increasing the complexity of the system. Computer simulation showed that the proposed algorithm can track the time delays adaptively and, consequently, improve the channel estimation performance.展开更多
The semi-global stabilization problem for a class of nonlinear systems with state time-delay is addressed in this paper. By using Lyapunov-Krasovskii functional method and homogeneous dom- ination approach, a homogene...The semi-global stabilization problem for a class of nonlinear systems with state time-delay is addressed in this paper. By using Lyapunov-Krasovskii functional method and homogeneous dom- ination approach, a homogeneous observer and an output feedback controller with a scaling gain are designed. Then the sealing gain is adjusted such that the closed-loop system is semi-global asymptoti- cally stable. A numerical example is presented to illustrate the effectiveness of the obtained results in this paper.展开更多
文摘The problem of discrete-time model identification of industrial processes with time delay was investigated.An iterative and separable method is proposed to solve this problem,that is,the rational transfer function model parameters and time delay are alternately fixed to estimate each other.The instrumental variable technique is applied to guarantee consistent estimation against measurement noise.A noteworthy merit of the proposed method is that it can handle fractional time delay estimation,compared to existing methods commonly assuming that the time delay is an integer multiple of the sampling interval.The identifiability analysis for time delay is addressed and correspondingly,some guidelines are provided for practical implementation of the proposed method.Numerical and experimental examples are presented to illustrate the effectiveness of the proposed method.
文摘This paper addresses the problem of channel estimation for broadband MIMO-OFDM systems. An improved channel estimator with multipath time delay detection and channel gain estimation is proposed. In the algorithm, we used the correlation of the channel taps and a well-designed adjustment scheme to increase the accuracy of the time delay detection. The most attractive advantage is that the complicated matrix calculation is replaced by search steps which can acquire the channel order and estimate the channel parameters without significantly increasing the complexity of the system. Computer simulation showed that the proposed algorithm can track the time delays adaptively and, consequently, improve the channel estimation performance.
基金supported by the National Natural Science Foundation of China under Grant Nos.61374038,61473079,and 61374060
文摘The semi-global stabilization problem for a class of nonlinear systems with state time-delay is addressed in this paper. By using Lyapunov-Krasovskii functional method and homogeneous dom- ination approach, a homogeneous observer and an output feedback controller with a scaling gain are designed. Then the sealing gain is adjusted such that the closed-loop system is semi-global asymptoti- cally stable. A numerical example is presented to illustrate the effectiveness of the obtained results in this paper.