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RFSG/RFSA FSK modulation/demodulation

Hi all!

I'm trying to transmit and receive an output bit stream, by modulating and demodulating an RF signal.

The signal is a FSK modulated 44 bits (24 bits - data bits and 20 bits - sync bits) defined users. 

I want to receive 24 data bits.

I'm using MT RFSG Generate FSK.vi and MT niRFSA FSK Trellis Diagram.vi. 

I'm using PXI-5610 RF Upconverter, PXI-5421 AWG; NI PXI-5652 RF Signal Generator, PXIe-5601 RF Downconverter, NI PXIe-5622
16-Bit IF Digitizer.

What values of parameters on Front Panel using?

 

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Message 1 of 5
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Hi Odiniz,

 

Did you have a question about any of the specific parameters or are you just unsure as to what to put for most of them? In many cases you just need to specify the same value in the RFSG and RFSA VIs so that they can communicate, but I would recommend using the Context Help (Ctrl+H) and reading about the different controls and properties they are setting. That way you can define the VIs to work correctly for your application, and also make sure you stay within the allowable range of values for each setting.

 

Regards,

Peter W.

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Hello, Peter W!

Thank you again for your answer. 

I have a question about frequency of a digital stream before upconverter. If to send a simple bit stream (example, 101101101) on the modulator (2-FSK) and to establish values Samples Per Symbol = 16, Symbol Rate = 100kHz. How to calculate frequency here?

 

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Hi Odiniz,

 

Are you trying to determine the IQ Rate that will be output? When using 2-FSK the bits per symbol is 1 so the frequency of the digital stream will be equal to that of the symbols, which you specified as 100kHz. The IQ rate will be Symbol Rate * Samples Per Symbol, or 1.6 MHz in your case. Does that answer your question?

 

Regards,

Peter W.

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Peter W,

Thanks for the response! I have't questions

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