This example demonstrates how to use a coprocessor-based demodulator to demodulate an SOQPSK modulated signal using NI-RFSA and NI Data Link Test Framework.

Complete the following steps.
  1. Navigate to <LVAddons>\dltf\1\examples\Data Link Test Framework\Modems\SOQPSK\Host\Demodulator and open SOQPSK Demodulator.vi.
  2. Use the VST Device Name control to select the VST.
  3. Use the Coprocessor Device Name control to select the coprocessor.
  4. Use the Coprocessor Bitfile Path control to select the correct modem bitfile for the selected VST and coprocessor.
    Table 29. SOQPSK Demodulator Compatible Bitfiles
    Coprocessor VST Bitfile
    PXIe-6594 PXIe-5840/5841 soqpsk_modem_dmsc_6594_00.lvbitx
    PXIe-7903 PXIe-5840/5841 soqpsk_modem_dmsc_7903_00.lvbitx
    PXIe-7903 PXIe-5842 soqpsk_modem_dmsc_7903_01.lvbitx
    PXIe-7915 PXIe-5840/5841 soqpsk_modem_dmsc_7915_00.lvbitx
  5. Adjust the Signal Parameters and RF Acquisition Settings to match the settings configured for the corresponding modulator.
  6. Run the VI.
    • The front panel graph displays the constellation.
    • The Bit Error Rate indicator displays the calculated bit error rate. Click the Reset BER button to reset the calculation.
    • The string indicator displays the example status.
    • The Bitfile Redownloaded indicator displays whether the bitfile was downloaded to the coprocessor for the current run of the example.
  7. Stop the example by clicking the Stop button or closing the window.