Abstract:

In order to solve the problem that is difficult to identify the faint modal with subspace algorithm driven by covariance, an improvement was put forward which chosen the data according to data efficient ratio. The method applied data efficient ratio to choose the data from tests, which could improve the auto-correlation energy proportion in the covariance matrix piece to realize the identification of faint modal. The simulation was carried out to verify the method, which proves the method is effective. The results show that the method can improve the identification quality effectively.

Key words: covariance, subspace, diagonal dominate, data efficient ratio

摘要：

针对协方差驱动子空间模态参数辨识方法难以识别弱小模态的问题，提出了一种根据数据有效率选择数据块的改进方法。该方法采用数据有效率来选择协方差矩阵块，以提高自相关能量在协方差矩阵中的比例，从而实现对弱小模态的识别。对该方法进行了仿真实验验证，验证结果表明，这一方法可以有效提高弱小模态的辨识质量。

关键词: 协方差, 子空间, 对角占优, 数据有效率