Inverse Filter

[Biswa]

Hi there, I am measuring the output of a mechanical manipulator in response to band
limited gaussian white noise. This then allows me to calculate the transfer function using -
cross-power spectral density of the stimulus and the response divided by the auto-PSD of the
stimulus. I have been able to achieve this in matlab. Now, I want to nullify the effect of the
manipulator using a inverse filter with 1/transfer function of the manipulator. This will
ensure that the noise that I inject in the manipulator passes faithfully without imposing the
transfer function of the vibrator. I am using invfreqz for getting the filter coefficients in matlab.

How can I design an arbitrary filter in labview with filter coefficients exported from matlab ? Best, BSG

[Paul_m6]

(I'm not sure if this is what you want), you can create a IIR filter using the coefficients with this block:

Signal processing/filters/adavanced IIR/IIR filter

or in the point by point version:

Signal processing/Point by point/filters/IIR filter






Mensaje editado por Paul_m6

[RER]

Dear Biswa,

Firstly, could I enquire about the version of LabView you are using? LabVIEW 8.0 introduced MathScipt, a high-level text-based programming language generally compatible with m-file script syntax. Furthermore, you can create script nodes only in the LabVIEW Full and Professional Development Systems.

So, if you do have the requisite versions of LabView, then please see the following tutorial, which will walk you through importing your data into LabView…

http://zone.ni.com/reference/en-XX/help/371361D-01/lvhowto/importing_or_exporting_hiq/

If you do not have access to the script nodes, then all versions of LabView you should be able to complete the following steps to exchange data between LabVIEW and the MATLAB environment, the process is straightforward as long as you are using ASCII format.

 

1. To save a vector or a matrix X in ASCII format with tab delimiter, enter the following in the command window or m-script file in the MATLAB® environment:

>>SAVE filename X   -ascii -double -tabs

This creates a file whose name is filename, and it contains the data X in ASCII format with a tab delimiter.

2. Import the file into LabVIEW using the Read From Spreadsheet File VI located on the Programming»File I/O palette.

 

Finally, you may be interested in the following knowledge base article…

How do I Manipulate the Coefficients and Floating Point Notation In the Filter VIs from the Advanced Analysis Library?

http://digital.ni.com/public.nsf/allkb/42D101AFC3E1978686256521005E1C78?OpenDocument

I hope this has been of some use to you,

Best wishes,