Adaptive filtering to cancel out noise from an pulse signal

[xinxingwang@hotmail.com]

Hi mboyz,

Your application is a typical adaptive noise cancellation problem. Randall has provided a solution of point by point LMS for you. Actually, NI has provided an adaptive filter startup kit. You can find it at this link (http://www.ni.com/labs). You will have more comprehensive adaptive filtering algorithm VIs and examples with this startup kit. But in order to play with this kit, you need to upgrade your LabVIEW to LabVIEW 8.2. 🙂

By the way, Randall's VI acquires the data using 1 sample (on demand) timing mode. It might not assure that the data sample is acquired on strictly equal intervals.  In addition,  the filter order will affect the loop rate. It might not be a good timing mode.

Usually adaptive noise cancellation problem can be solved by processing data block by block.  I have used LV 8.0 to create block based LMS VI and combine it with continuously data acquisition VIs in the example.

Please feel free to let me know if you have any questions.

[Herrman]

Please, any one could explain for me this block diagrame of the adaptive filter 

[Kelsey_Weaver@NI]

Hi Herrman,

Your question doesn't seem related to LabVIEW, so you may have trouble getting a response from the LabVIEW community. Block diagrams in LabVIEW have a different meaning than your typical engineering block diagrams. You may want to post your question to a different forum. Good luck!

LabVIEW Block Diagram Tutorial

http://www.ni.com/white-paper/7565/en/