[OT] Is LABview right for me?

[ALFREDII]

Hello, I am new here and have NO experience with LABview. Currently, I am working on a project that requires me to analyze a signal in frequency versus time (spectrogram) format. The signal that I am working with is in the form of modulated ultrasonic sound and is centered at around 40khz. I have been unable to find a spectrogram program that works with ultrasonic frequencies (they all seem to use the PC’s soundcard as the input device and the frequency is therefor limited to 20khz). After doing some research, I decided that LABview might work for this application but I am not sure how to get started. I have a Pico Scope PC based oscilloscope that I could use as the input device for LABview but I don’t know what programs I would need to view a spectrogram of my signal. It is also important to note that the spectrogram should run in real time. Will LABview be able to fulfill the needs of this project? If not, does anyone know of any other software that would work in my situation? I appreciate any advice you can give me.

[LabViewGuruWannabe]

One of the Applications Engineers at NI would be glad to help you out, I'm sure. This forum is a great resource for specific problems, as well as meeting others who have done the same things as you are trying to do, so you are on the right track.

I haven't specifically done the type of signal analysis that you are talking about, but I am 99% certain that LabVIEW can easily handle what you need. However, as with nearly all programming languages, there is a learning curve. As long as you have ample time to learn how to use it, LabVIEW should serve you well. It is designed specifically for data aquisition, test and measurement, and even has some neat reporting tools for analyzing and presenting your data.

Good luck!

[Tom Haggerty]

I created a mapping station that detected the range of  ultrasonic parking aid sensors in my old job (8 years ago).  The frequencies were similar to your application.  I used LabView on the project and it worked perfectly in that setup.  I would recommend you get training in LabView and contact your local representative for help on hardware and interfacing.  Your local rep should be able to help you get the proper equipment, either directly or by getting you in contact with a subject matter expert.

Good luck

Tom

[Barp]

Additional to contact the sales rep, you could also look at our manuals and documentation online from our website. There you can verify if LabVIEW has the function you are looking for. For spectrogram, we have two VIs (Notice that those VIs are NOT available in the Base package of LabVIEW):

https://www.ni.com/docs/en-US/bundle/labview-api-ref/page/vi-lib/gmath/trans-llb/stft-spectrograms-v...

https://www.ni.com/docs/en-US/bundle/labview-api-ref/page/vi-lib/gmath/trans-llb/wvd-spectrogram-vi....

If you can have access to special toolkits like Advanced Signal Processing Toolkit (ASPT), you can do Gabor Analysis or Waterfall:

https://www.ni.com/en/shop/labview/select-edition.html

https://www.ni.com/docs/en-US/bundle/labview-advanced-signal-processing-toolkit-api-ref/page/lvasptc...

You could also look at our tutorials on that area:

http://zone.ni.com/devzone/cda/tut/p/id/4502 

Probably after you look at this content, you will notice that LabVIEW is very good at data acquisition AND math/signal processing with a 'killer' user interface...

Good luck!

Message Edited by Barp on 01-10-2008 08:27 AM

[Ben]

[Set wise-crack mode = T]

"

... LABview. ...LABview ...LABview ...LABview...

"

I would expect you would love LabVIEW, there is no syntax! That is one of the thing I like best.

[Set wise-crack mode = F]

Ben

[Joeri_Wingelinckx_NI]

Hello,


LabVIEW is made for such kind of tasks.
As of the Full Development version it has a complete library with analysis functions like FFT.  If the included functions can't do the job there is a specific Sound & Vibrations toolkit which give you a set of additional libraries.

There are some examples delivered with LabVIEW to analyse sound data using a soundcard.
But as you say, a PC soundcard is too limited to do good measurements
Have a look at this USB measurement module: http://sine.ni.com/nips/cds/view/p/lang/en/nid/202152
If you don't need this precision and speed there are alternatives in the same product range.

As you have a Picotech Scope you should check on the Picotech website if they have a LabVIEW driver for your oscilloscope. If yes, you can simply install it and you have an additional library in LabVIEW to communicate with your instrument.
If Picotech doesn't have the driver have a look at the National Instruments Instruments Driver Network: http://www.ni.com/idnet for a LabVIEW driver developed by NI or LabVIEW users.
LabVIEW also includes the Instrument I/O assistent which give you a wizard tool to create you own functions to communicate with your scope.

One thing I would like to check with you is your understanding of "Real-Time".
Do you want to display the measured and analysed data immediately?
In that case LabVIEW and a normal PC will do.  Windows is not a real time operating system but LabVIEW will display the measured signal almost immediately.  Microseconds delays can occurs if you move very rapidely with your mouse or due to your virusscanner.
Keep in mind that LabVIEW is currently the only software program for test and measurement which really can use the multiple cores of your processors. 
If National Instruments talks about Real-Time then they mean determistic decision making in for example control applications.  LabVIEW can using the LabVIEW Real-Time module run in real-time, but as far I can judge it you will not need that.

I would like to advise you to call you local National Instruments inside sales representatives.  These engineers will be able to advise you the best solution to reach your goal.


Best regards,
Joeri Wingelinckx

[ALFREDII]

Thanks for all the input, I think that LABview sounds like the best option for this project. When I say real-time, I simply mean updating continuously from the input device. If there is a short lag time it is not an issue, I just need to be able to see the spectrogram output at approximatly the same time as the signal occurs. I am however a bit concerned that my computer will have trouble running LABview. It is a lapot running XP with a cingle 1.4Ghz Celron M processor and 256MB RAM. Would this be powerful enough? Thanks again for the help. 

[Joeri_Wingelinckx_NI]

Here you have the minimum requirements: http://www.ni.com/labview/requirements 

[Joe_H]

The PC that you have is barely at the minimum of the requirements. LabVIEW will run very slow in the editing of a VI. You will want to upgrade your computers memory to at least 512MB.

LabVIEW will do everything that you want it to do for this project.