Specifies the I/Q rate for the acquisition. The value is expressed in samples per second (S/s).

For the PXIe-5663/5663E/5665/5667/5668, when you set the Digitizer Sample Clock Timebase Source property to OnboardClock, the digitizer bandwidth is greater than or equal to the coerced IQ rate times 0.8.

Note For the PXIe-5663/5663E/5665/5667/5668, NI-RFSA enables dithering by default. The dither noise can appear in your passband and affect your measurements. Refer to the Digitizer Dither Enabled property for more information about dithering.

Supported Devices: PXIe-5644/5645/5646, PXI-5661, PXIe-5663/5663E/5665/5667/5668, PXIe-5820/5830/5831/5832/5840/5841/5842/5860

Related Topics

I/Q Modulation


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Inputs/Outputs

  • civrn.png instrument handle —

    instrument handle identifies your instrument session. instrument handle is obtained from the niRFSA Initialize VI or the niRFSA Initialize With Options VI.

  • cdbl.png IQ rate (S/s) —

    IQ rate specifies the I/Q rate for the acquisition. The value is expressed in samples per second (S/s).

  • cerrcodeclst.png error in —

    error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

  • iivrn.png instrument handle out —

    instrument handle out passes a reference to your instrument session to the next VI. instrument handle is obtained from the niRFSA Initialize VI or the niRFSA Initialize With Options VI and identifies a particular instrument session.

  • ierrcodeclst.png error out —

    error out contains error information. This output provides standard error out functionality.

    • Details

    Actual signal bandwidth is limited for all supported devices by the anti-aliasing filter. Further device-specific limitations are as follows.

    PXI-5661—You should not need to configure an IQ rate higher than 25 megasamples per second (MS/s) because the PXI-5600 RF downconverter bandwidth is 20 MHz. If you configure a higher I/Q rate, you may see aliasing effects at negative frequencies because the IF frequency of the PXI-5600 is 15 MHz.

    PXIe-5663/5663E—Maximum allowed instantaneous bandwidth depends on the downconverter center frequency you use. Refer to the PXIe-5601 RF downconverter overview for more information about instantaneous bandwidth.

    PXIe-5665—Actual signal bandwidth is limited by the preselector and the combination of the chosen IF filter and anti-aliasing filter. Maximum allowed instantaneous bandwidth is independent of the downconverter center frequency for frequencies less than 3.6 GHz. At frequencies greater than 3.6 GHz, if your device supports the preselector (YIG-tuned filter) and you have enabled it for your application, the maximum allowed instantaneous bandwidth is limited to the instantaneous bandwidth of the preselector. Refer to the NI PXIe-5665 Specifications for more information about instantaneous bandwidth limits.

    PXIe-5667—Actual signal bandwidth is limited by the preselector and the combination of the chosen IF filter and anti-aliasing filter. Maximum allowed instantaneous bandwidth depends on the downconverter center frequency you use. Refer to the NI PXIe-5667 Specifications for more information about instantaneous bandwidth limits.

    PXIe-5668—Actual signal bandwidth is limited by the FPGA image that is downloaded upon opening the session to the PXIe-5624 digitizer. Maximum allowed instantaneous bandwidth depends on the downconverter center frequency you use. Refer to the PXIe-5668 Specifications for more information about instantaneous bandwidth limits.

    PXIe-5644/5645/5646, PXIe-5830/5831/5832/5840/5841/5842—Maximum allowed instantaneous bandwidth depends on the downconverter center frequency you use. Refer to the specifications document for your device for more information about instantaneous bandwidth limits.