PXIe-5605 Preselector

The PXIe-5605 contains an optional yttrium-iron-garnet (YIG)-tunable preselection filter (preselector) that you can use to reduce unwanted frequency components from the RF input for frequencies between 3.6 GHz and 14 GHz.

The preselector is a high Q filter that suppresses signals outside the preselector passband by a typical amount of 75 dB. NI-RFSA enables the preselector by default for frequencies greater than 3.6 GHz. The preselector rejects the image frequencies and reduces LO reradiation by filtering these spurious signals. You can use the NI-RFSA Preselector Enabled property to enable or disable the preselector.

Enabling the PXIe-5605 preselector has the following implications:
  • The preselector introduces amplitude and phase errors to the incoming signal at the RF IN connector. These errors are not corrected by NI-RFSA.
  • The preselector has a varying passband ripple that changes with the device center frequency.
  • The preselector draws current when enabled, which causes the module temperature to increase.
  • The preselector bandwidth changes with temperature and increases as the tuned frequency increases. The preselector can also be affected by vibrations to the PXIe-5605 module.