How to export from multism to matlab

[fouda]

AA,

I downloaded update package from http://joule.ni.com/nidu/cds/view/p/id/2194/lang/en   and installed it

then rerun given simulations and get SNR .

But I am designing  ADC and  I need to calculate SNR  over fixed  bandwidth  (0 --> Fs), How I can do that ?

[_user32]

fouda,

I created another LabVIEW instrument SNRv2 that allows you to place a continuous filter on the incoming signal prior to the SNR calculations.  This should allow you to band limit the SNR calculation with a LPF from 0 -> fs.   For the SNR measurement to be accurate, the filtered waveform will need to settle after the simulated waveform has gone through the number of samples specified in "Sample Size".

If you change the filter type, order or cutoff frequency, you will need to either restart the simulation or wait until 'Sample Size' has passed for an accurate SNR measurement.   You will not be able to run SNRv1 and SNRv2 together as they share some resource files, so it may be best to delete the SNRv1.llb as the SNRv2.llb is a superset of the previous SNR method.

Regards,

Pat

[_user32]

fouda,

Here is an updated Multisim VI for SNR that doesn't share the same libraries (so it should be loadable with SNRv1 if interested)...  

Also I've created another Multisim v11 example to test the new SNR_bw - I've added a thermal noise source at the input and output of a simple amplifier - the noise source has a bandwidth of 1Mhz - and you can clearly see that adding a max bandwidth does filter the noise above Fs and adjusts the SNR calculation accordingly.

Regards,

Pat

[fouda]

Thanks ,

I want to know how to create this VI

and I need also to see PSD (power spectral density) like in lab view to check noise shaping 

[_user32]

fouda,

There is an introductory tutorial here:

http://zone.ni.com/devzone/cda/tut/p/id/5635

If you are already familiar with LabVIEW, using the tutorial for the first few VIs that you build will help (I recommend doing something simple to start), but once you get the hang of it, you can really get these cranked out in no time (assuming the functions already existing in LabVIEW) once you learn how to build the .llb files with the correct 'stuff' in them.   You can increase the complexity of the Multisim VIs by adding additional setup, graphing, cursors, analysis or multiple measurements in the same.   If you add a lot of stuff to the VIs, this can make your builds a little more difficult if you include more of the advanced LabVIEW libraries, but it shouldn't be too challenging once you learn a few techniques.   If you need help, please post back.

By the way, the Multisim LabVIEW templates already exist when you install Multisim (C:\Documents and Settings\All Users\Documents\National Instruments\Circuit Design Suite 11.0\samples\LabVIEW Instruments\Templates).   I recommend copying these into a new 'working' directory and modifying the code from there.

Also remember

Multisim v10.1 works with LV 8.6

Multisim v11 works with LV 2009 and LV 8.6

Multisim v11.0.1 and higher works with LV 2009 and LV2010, and you can make it work with LV 8.6 instruments if you use the compatibility libraries I mentioned earlier in this thread.

Regards,

Pat