This example demonstrates how to use a coprocessor-based modulator to generate a Pulsed BPSK signal using NI Data Link Test Framework.

Complete the following steps.
  1. Navigate to <LVAddons>\dltf\1\examples\Data Link Test Framework\Modems\Pulsed BPSK\Host\Modulator and open Pulsed BPSK Modulator.vi.
  2. Use the VST Device Name control to select the VST.
  3. Select the Modem Mode that corresponds with the demodulator that you will be running.
    • Select Continuous for an NI-RFSA-based demodulator.
    • Select Interactive for an RFmx-based demodulator.
  4. Use the Coprocessor Device Name control to select the coprocessor.
  5. Use the Coprocessor Bitfile Path control to select the correct modem bitfile for the selected VST and coprocessor.
    Table 22. Pulsed BPSK Modulator Compatible Bitfiles
    Coprocessor VST Modem Mode Bitfile
    PXIe-6594 PXIe-5840/5841 Interactive pulsed_bpsk_modem_dec_dmsc_6594_00.lvbitx
    PXIe-6594 PXIe-5840/5841 Continuous pulsed_bpsk_modem_dmsc_6594_00.lvbitx
    PXIe-7903 PXIe-5840/5841 Interactive pulsed_bpsk_modem_dec_dmsc_7903_00.lvbitx
    PXIe-7903 PXIe-5840/5841 Continuous pulsed_bpsk_modem_dmsc_7903_00.lvbitx
    PXIe-7903 PXIe-5842 Interactive pulsed_bpsk_modem_dec_dmsc_7903_01.lvbitx
    PXIe-7903 PXIe-5842 Continuous pulsed_bpsk_modem_dmsc_7903_01.lvbitx
    PXIe-7915 PXIe-5840/5841 Continuous pulsed_bpsk_modem_dmsc_7915_00.lvbitx
  6. Adjust the Signal Parameters and RF Acquisition Settings to match the settings configured for the corresponding demodulator.
  7. Run the VI.
    • The front panel graph displays a generated constellation.
    • The string indicator displays the example status.
    • Use the Generation Mode control to change the output signal of the modulator:
      • Select Pulsed BPSK Modulator generate a modulated signal combined with noise.
      • Select AWGN Generator to generate a noise-only signal.
    • Use the Eb/N0 (db) control to adjust the noise added to the modulated signal on the coprocessor.
    • Use the Power Scaling control to set the scaled output power value (1 = full scale).
    • Use the Sweeping Type control to set the behavior of the modulator when the Run Sweep button is clicked:
      • Select Eb/N0 to sweep the Eb/N0 value from the current set value to down to 0 and back to the start point.
      • Select Power to sweep the Power Scaling value from the current value down to 0 and back to the start point.
    • Click the Run Sweep button to run the sweep function defined in the Sweeping Type Control.
    • The Bitfile Redownloaded indicator displays whether the bitfile was downloaded to the coprocessor for the current run of the example.
  8. Stop the example by clicking the Stop button or closing the window.