Solution
The FPGA in the VST provides a way to customize its functionality at the Hardware Level. By programming the FPGA chip with the LabVIEW FPGA Module, you could add custom functionality such as control a device under test (DUT) in real time, dynamically control/sequence the vector signal generator (VSG) or vector signal analyzer (VSA), or add real-time signal processing to the instrument.
Refer to the white paper
An Introduction to Instrument Driver FPGA Extensions to see the different ways you can customize VSTs functionality.
In case you need to perform functions such as modulation and demodulation (e.g., BPSK, GFSK, AM, FM), or perform spectral measurements without any custom functionality, you can use NI-RFmx, NI-RFSA, or NI-RFSG.
Refer to the
NI Vector Signal Transceivers Help to better understand the different options for programming a VST.