Performance of tfestimate at high frequencies

5 次查看（过去 30 天）
Angelica
Angelica 2014-9-8
回答： Harryboy 2019-10-10
Hi, It was recommended to me to try to use the function tfestimate instead of the system identification toolbox to try to do sys id using data driven modelling. To first test my understanding of tfestimate, I took a known system (low pass filter, cutoff = 5Hz) and a step input, and used simulink to generate the output. I then fed the input/output into tfestimate to see what it does; below are the results.
For parameters I used window = 2^10 (largest power of 2 which was less than the length of my input vector), and default 50% overlap and nfft = 2^10 as well (lower nfft values had similar trends,just less noise). At low frequencies, it looks almost alright. But for higher frequencies, the tfestimate results are way off. I don't have much background in spectral analysis and therefore am not too confident in parameter selection. I feel like tfestimate must be able to do a better job if configured correctly. Can please give me any suggestions for using this function?
Thank you!
tfestimate Output:

请先登录，再回答此问题。

回答（1 个）

Harryboy
Harryboy 2019-10-10
Hello Angelica,
I also have a system with a frequency mode at 6500 Hz, and even for me the tfestimate is given NAN for amplitude values. Did you find the right way to configure the command?
Thank you and kind regards,
Hari

类别

在 Help Center 和 File Exchange 中查找有关 Parametric Spectral Estimation 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by