In order to improve the identification accuracy of instantaneous frequency from civil engineering structures,a new method called local maximum synchrosqueezing generalized S-transform method(LMSSGST)is proposed.In the proposed method,the generalized S-transform is performed on the response signals of structure at first.Then,the instantaneous frequency can be estimated by taking partial derivative of the time frequency coefficients with respect to time.Finally,the local maximum synchrosqueezing operator is used to reassign the time-frequency coefficients.A numerical case of two-story frame structure and a test of seven-story reinforced concrete shear wall structure are used to verify the effectiveness and accuracy of the proposed method.The results demonstrate that that the LMSSGST method behaves better than local maximum synchrosqueezing transform.It not only enhances the accuracy of instantaneous frequency identification,but also improves the time-frequency energy concentration.
关键词
广义S变换/局部最大值同步压缩变换/时频系数/瞬时频率
Key words
generalized S-transform/local maximum synchrosqueezing transform/time frequency coefficient/instantaneous frequency
万方数据