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How to demodulate FSK/ASK Spectrum into BitStream

Hey guys,

 

I have the following problem.

I've got an spectrum and I need to make a FSK Modulation on it. Also a ASK has to be possible...
 And I'm not able to get a correct bitstream with the NI Modulation Toolkit :(. I have used some of the examples and tried to use them for my spectrum but they dont give me correct bitstreams...

 

As long as I know I have to use the "MT Demodulate FSK.vi" but it want work :(.

 

Anybody can help? I have never done that before.

 

Hopefully many thanks in the beginning,


Adrian

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Does nobody has an idea :/?

CLA
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Hi Adrian,

 

I still have a little problem understanding your problem.

 

Could you upload an executable example project with all necessary VIs, so that I could try to have a look at it and possibly test it?

 

What is the exact problem? The compilation of the bitstream cancels and you get an error? If so please upload a screenshot of all the information.

 

Thanks in advance!

 

Best regards

Christoph

Staff Applications Engineer
National Instruments
Certified LabVIEW Developer (CLD), Certified LabVIEW Embedded Systems Developer (CLED)


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Hey Christoph,

 

my actual problem is that i only get a bitstream full of "0" values. This cannot be the correct FSK demodulated bitstream out of my constant spectrum.

 

My spectrum is in the control "unit converted spectrum" and is visible within the graph.

 

I need somebody which can help me to demodulate this spectrum to get a correct bitstream. I have the NI Modulation Kit and have added some libs within my attached zip file. Hope this is legal to do so...

 

 

I am new to LV so I dont know how to build up a standalone system for this VI with all the needed librarys.

 

Hope anybody can help me to get a correct output bitstream from my given spectrum.

 

Peace Adrian

 

 

Screen_only_zero_bits_in_outputstream.png

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Okay somehow I am not able to add a zip file with all my libs from the NI Modulation ToolKit...

Guess then you arent able to help me? Or do you have it :)`?

CLA
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Hey Adrian,

 

I looked into your file and tried to follow the data flow in the "MT Demodulate FSK.vi" and it seems like the "Complex to Polar"-function (see screenshot) returns only zeros since your "input complex waveform" is NOT complex! You do not have a complex spectrum, so the "Complex to Polar"-function only returns zeros which finally results in a empty bit-stream.

 

Best regards

Christoph

 

 

Staff Applications Engineer
National Instruments
Certified LabVIEW Developer (CLD), Certified LabVIEW Embedded Systems Developer (CLED)


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