Multi-Channel FM RF Generation

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Overview

The aim of this example is to show the addition of IQ data and normalisation of multiple IQ waveforms added together to create a multi channel output similar to the RFSG MultiTone shipped examples.

Description

This example is to extend the shipping example "RFSG Multitone - Uniform Spacing.vi" with Frequency Modulation on each of the channels.

The principle is to use the DC conversion to a frequency offset to translate the signal to each channel. E.g. if a +-1 amplitude sine wave FM'ed at 1kHz deviation translates to a central signal of +-1kHz to 0Hz carrier, then a +-1 amplitude sinewave with an offset of 3 FM'ed at 1kHz deviation translates to a signal that is 2kHz to 4kHz (or a +-1kHz to 3kHz).By doing this, we're saving on calculating the frequency offset to apply to move the channels from '0'Hz.

The example screenshot taken below was using the PXIe-5644R with the output looped back in to the input and using the RFSA soft front panel with a reasonably narrow resolution bandwidth.

Requirements
* LabVIEW 2013 SP1 or Compatible
* Compatible NI-RFSG
* Spectral Measurements Toolkit
* Modulation Toolkit

Steps to Implement or Execute Code
* Open the "Insert Data Into Array-LV2012 NIVerified.vi"
* Set the controls to appropriate values.
* Click the Run arrow.
* To change the view of the generated IQ data in the spectral domain, you can change the graph x axis and change the FFT Size
* Alternatively, connect the output of the hardware VSG to a spectrum analyser to see the real generated signal.

Additional Information or References

Notes:
* Some wide band waveforms may cause out of memory errors. If this occurs, consider reducing the time duration to calculate for.
* The example has a simulated VSG, so no hardware is required to see the output. For a loop back test, we need to change the "Simulte=1" to "Simulate=0". Currently we are simulating a 5673E.