writer
544
edits
Difference between revisions of "Modal ODS and Modal(EMA-OMA) identification"
Jump to navigation
Jump to search
Modal ODS and Modal(EMA-OMA) identification (view source)
Revision as of 11:23, 31 May 2021
, 11:23, 31 May 2021→OMA BroBand (OBFD)
| Line 483: | Line 483: | ||
=====Estimate the HPSD===== | =====Estimate the HPSD===== | ||
You should begin the HPSD estimation by using the "Signal Processing Wizard". The main procedures are as the following. | |||
1) Select to estimate the Output Half PSD: | |||
[[File:image_2021-05-31_121320.png|600px]] | |||
2) Remove the trend of signal: | |||
[[File:image_2021-05-31_121754.png|600px]] | |||
3) Perform decimation if necessary: | |||
[[File:image_2021-05-31_121826.png|600px]] | |||
4）Set the FFT parameters: | |||
[[File:image_2021-05-31_121859.png|600px]] | |||
5) Apply the exponential window function: | |||
Here the exponential window is asked to reduce the leakage in the processing of H-PSD estimation. Usually the coefficient of exponential window can be set as 50%, which means the exponential function reduces to 1/e when the time is 50% sampling period. | |||
[[File:image_2021-05-31_122029.png|600px]] | |||
6) Begin signal processing, and set the number of correlation lags: | |||
Usually the lags should be set to 256. | |||
[[File:image_2021-05-31_122135.png|400px]] | |||
For the multiple-setup case, the references are set automatically. But for the one-setup case, you may asked to select the references manually. All the measurements are selected as references by default. Sometimes this default setting may cause too large calculation workload, and you need select some proper references according to all kinds of factors, such as the structure of test model, the positions of measurement points | |||
[[File:image_2021-05-31_122242.png|400px]] | |||
In the above dialog, you can select or unselect all by clicking the column header of "Index". | |||
=====Begin Modal Identification===== | =====Begin Modal Identification===== | ||
The modal identification procedure is the same as [[Modal_ODS_and_Modal(EMA-OMA)_identification#EMA_Broadband_.28BBFD.29|EMA BroBand]]. | The modal identification procedure is the same as [[Modal_ODS_and_Modal(EMA-OMA)_identification#EMA_Broadband_.28BBFD.29|EMA BroBand]]. | ||