Acquisition:Device Instantaneous Bandwidth (Hz)
- Updated2025-10-14
- 4 minute(s) read
Specifies the instantaneous bandwidth of the device in Hz. The instantaneous bandwidth is the effective real-time bandwidth of the signal path for your configuration.
Specify the maximum instantaneous bandwidth needed for your measurement. NI-RFSA coerces the actual IF filter to use based on other measurement constraints such as the IF Filter Bandwidth property and the Digital IF Equalization Enabled property.
To change the value that NI-RFSA uses for the maximum size of multispan acquisition subspans, use the FFT Width property.
The Signal Bandwidth, centered at the IQ Carrier Frequency, must fit within the Device Instantaneous Bandwidth, which is centered at the Downconverter Center Frequency.
PXI-5661�The PXI-5600 RF downconverter instantaneous bandwidth is 20 MHz.
PXIe-5663/5663E�Your 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�Your maximum allowed instantaneous bandwidth is independent of the downconverter center frequency. Refer to the NI PXIe-5665 Specifications for more information about instantaneous bandwidth.
PXIe-5665 (14 GHz), PXIe-5668—If you have enabled the preselector for the PXIe-5605/5606, the device instantaneous bandwidth value is only a typical specification. For multispan acquisitions, NI-RFSA uses this typical specification as the maximum size for the acquisition subspans.
PXIe-5693—This property is read-only for the PXIe-5693. The value for the device instantaneous bandwidth depends on the value for the RF preselector filter.
PXIe-5694/PXIe-5667—If your application uses the PXIe-5694 as part of an PXIe-5667 spectrum monitoring receiver or the PXIe-5694 as a stand-alone device, NI-RFSA determines the appropriate IF filter to use based on the value that you set for this property.
| Device Instantaneous Bandwidth Property Value Frequency Range | IF Filter |
|---|---|
| ≤30 kHz (IF Conditioning Downconversion Enabled property set to Enabled) | 30 kHz |
| >30 kHz and ≤400 kHz | 400 kHz |
| >400 kHz and ≤1.4 MHz | 1.4 MHz |
| >1.4 MHz and ≤5 MHz | 5 MHz |
| >5 MHz and ≤20 MHz | 20 MHz |
| >20 MHz (Signal Conditioning Enabled property set to Bypassed) | Bypass |
PXIe-5644/5645/5646—This property is read-only for the PXIe-5644/5645/5646. Refer to the specifications document for your device for more information about instantaneous bandwidth.
PXIe-5840/5841/5860—Your maximum allowed instantaneous bandwidth depends on the downconverter center frequency you use. Refer to the NI PXIe-5840/5841/5842/5860 Specifications for more information about instantaneous bandwidth. Set this property to select different device instantaneous bandwidths for a given downconverter center frequency. The device instantaneous bandwidth that you select is greater than or equal to the requested instantaneous bandwidth. If this property is not set, NI-RFSA uses the maximum allowed instantaneous bandwidth.
PXIe-5842—Your maximum allowed instantaneous bandwidth depends on the device's hardware options, configured device personality, and the downconverter center frequency you use. Refer to the NI PXIe-5842 Specifications for more information about instantaneous bandwidth and device personality. Set this property to select different device instantaneous bandwidths for a given downconverter center frequency. The device instantaneous bandwidth that you select is greater than or equal to the requested instantaneous bandwidth. If this property is not set, NI-RFSA uses the maximum allowed instantaneous bandwidth.
Default Value: N/A
Supported Devices: PXI-5600, PXIe-5601/5603/5605/5606 (external digitizer mode), PXIe-5644/5645/5646, PXI-5661, PXIe-5663/5663E/5665/5667/5668, PXIe-5693/5694, PXIe-5820/5830/5831/5832/5840/5841/5842/5860
Related Topics
PXIe-5830 Frequency and Bandwidth Selection
PXIe-5831/5832 Frequency and Bandwidth Selection
PXIe-5841 Frequency and Bandwidth Selection
Remarks
The following table lists the characteristics of this property.
| Short Name | Device Instantaneous Bandwidth |
| Data type | ![]() |
| Permissions | Read/Write |
| High-level VIs | N/A |
| Channel-based | No |
| Resettable | Yes |
