基于子空间比较的宽带信号下辐射源 功放"指纹"分类方法

 本文提出了一种基于功放宽带Volterra级数模型的辐射源"指纹"分类方法,以用于电子侦察对宽带信号源的特定辐射源识别.针对传统Volterra系统MIMO建模方法的适应性不足,以及系统辨识过程存在维数爆炸问题,本文推导出一种对编码类和调频类宽带信号都适用的MIMO建模方法,然后直接基于参数子空间比较来实现功放的指纹分类.对本方法的"独立性"和"可测性"进行了分析.数值仿真实验对子空间比较方法进行了验证.     

On the realization problem for stationary,homogeneous, discrete-time systems

For degree 2, stationary, homogeneous systems, we consider realizations in the form of state-affine difference equations, and in the form of feedback-free interconnections of stationary linear systems, adders, and multipliers. Realizability conditions are presented in terms of the symmetric transfer function (or kernel), and in terms of a new representation called the regular transfer function (or kernel). A procedure is given for constructing a minimal dimension state-affine realization, and the corresponding interconnection.     

A new symbolic calculus for the response of nonlinear systems

We present a new operational calculus for computing the response of nonlinear systems to various deterministic excitations. The use of a new tool: noncommutative generating power series, allows us to derive, by simple algebraic manipulations, the Volterra functional series of the solution of a large class of nonlinear forced differential equations. The symbolic calculus introduced appears as a natural generalization to the nonlinear domain, of the well known Heaviside operational calculus. Moreover, this method has the advantage of allowing the use of a computer.     

一种基于Volterra模型的非线性系统具有全解耦结构的递阶式自适应辨识方法

研究了在输入输出观测数据均含有噪声时如何对基于Volterra级数描述的非线性系统进行解耦自适应辨识的问题. 按照Volterra级数模型的伪线性组合结构, 采用总体最小二乘辨识技术的原理, 导出了一种总体全解耦辨识的思想. 从而建立了一种具有全解耦结构的递阶式自适应辨识算法, 给出了该算法的结构图. 相比于部分解耦辨识算法, 该算法的优点在于它能够在全噪声数据环境下得到更高的收敛速度和精度. 仿真研究的结果证明了本文方法的有效性.     

非线性系统广义脉冲响应函数的盲辨识

探讨减少非线性系统广义脉冲响应函数（GIRF）盲辨识所需计算量问题。 基于线性MIMO模型，应用多项式矩阵理论和子空间盲辨识技术，研究使用部分噪声向量对非线性Volterra系统的GIRF盲辨识方法。该方法的优点是能有效减少GIRF盲辨识所需的计算量。这对GIRF盲辩识方法的在线应用是有利的。仿真结果说明了这一方法的有效性。     

Volterra高阶核的新算法在航空涡轮转速控制上的应用

针对航空发动机的转速控制这个难题,提出了对非线性动态系统做建模研究的Volterra泛函方法的任意高阶核估计方法;该方法在核(kernel method)理论基础上,构造线性空间,将求解Volterra泛函各阶核的问题转化为求输出观测向量在希尔伯特空间(Hilbert space)子空间上的分量,利用线性空间中向量内积的求解而间接辨识出复杂的非线性动态系统;相对于其它在时域或频域估计Volterra核的理论,该方法数学基础牢固、计算量不随辨识精度增高而大量增加、理论上能够对任意高阶核进行估计,可对强非线性动态系统进行辨识。     

Collocation method for solving systems of Fredholm and Volterra integral equations

In this paper, a numerical method based on based quintic B-spline has been developed to solve systems of the linear and nonlinear Fredholm and Volterra integral equations. The solutions are collocated by quintic B-splines and then the integral equations are approximated by the four-points Gauss-Turán quadrature formula with respect to the weight function Legendre. The quintic spline leads to optimal approximation and O(h⁶) global error estimates obtained for numerical solution. The error analysis of proposed numerical method is studied theoretically. The results are compared with the results obtained by other methods which show that our method is accurate.     

Approximate solution of systems of Volterra integral equations with error analysis

This paper describes a procedure for solving the system of linear Volterra integral equations by means of the Sinc collocation method. A convergence and an error analysis are given; it is shown that the Sinc solution produces an error of order O(exp(?c N ^1/2)), where c>0 is a constant. This approximation reduces the system of integral equations to an explicit system of algebraic equations. The analytical results are illustrated with numerical examples that exhibit the exponential convergence rate.