在充分考虑线性动力系统的时域响应特性以及小波包分析的频率空间剖分特性的基础上,提出了一种基于虚拟响应信息提取的信号去噪新方法。虚拟响应虽然没有在结构动力检测过程中真实发生,但却是在某种激励下可以实现的一个响应,因此,根据虚拟响应信息同样可以进行结构系统的动力识别。数值研究表明,对于地脉动响应这种有效信号频带与噪声频带相互覆盖的低信噪比信号而言,小波闻值去噪法已无能为力,而基于虚拟响应信息提取的信号去噪方法则有较好的去噪效果。
A new signal de-noising method based on virtual response information is proposed, which considers fully the response property of linear dynamic system in time domain and the property of frequency space partitioned by wavelet package ana certain excitation, virtual responses can lys be is. Being a kind of realizable responses of structure under a used to identify the structural dynamics system deservedly. Seismic response information is a batch of low of measurement noise. The new de-noising m slgna ethod 1-noise-ratio data, whose valid frequency zone is full proposed in this paper can eliminate efficiently the noise in seismic responses, while threshold value de-noislng method based on wavelet analysis is of no effect. It is illustrated by numerical examples that response information, and the identification error the stiffness parameters can be identified with virtual corresponds to the measurement noise in principle.