中文摘要：

提出一种多输入多输出（MIMO）系统的宽频模态参数识别算法。该方法基于频响函数（FRF）的左矩阵分式模型（LMFD）,通过最小二乘法在z域内求解模态参数,避免了s域内矩阵的病态问题。针对左矩阵分式模型的特点,给出了一种通过主分量分析（PCA）建立稳定图的方法。指出了传统的频域多参考点（PRFD）方法与基于左矩阵分式模型识别方法之间的关系。最后采用GARTEUR模型仿真算例与飞机模型的实测算例对所提出的方法进行了验证,结果表明该方法具有良好的识别效果。

英文摘要：

A broadband modal parameter identification algorithm is proposed for a multi-input multi-output （MIMO） system. The algorithm is based on the left matrix fraction description （LMFD） of the frequency response function （FRF）. The modal parameters are achieved by using a least squares estimator so that the bad numerical conditions of the matrix can be avoided in the z domain. Considering the feature of left matrix fraction description,this article presents a construction method of the stabilization diagram by principal component analysis （PCA）. It also dwells on the relationship between the classical poly-reference frequency domain （PRFD） and the proposed method. A simulation case of a GARTEUR model and an application case of an aircraft model are employed to validate the algorithm. The results show that good effect is achieved by the proposed algorithm.