National Instruments NI PXIe-5624, Процедура калибровки

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NI PXIe-5624R Calibration Procedure
Verifying Absolute Amplitude Accuracy
This procedure verifies the absolute amplitude accuracy of the NI 5624R input channel.
Accuracy is specified using the calibration IP on the default 400 MHz acquisition FPGA image
provided in the Multirecord Acquisition sample project. The
Interactive Spectrum
Acquisition (Host).vi
provides a starting point for this procedure. The calibration IP
equalizes the frequency response and corrects for losses. Because a digital downconverter
(DDC) is used, multiple center frequencies are chosen in order to cover the entire specified
bandwidth. The response across 400 MHz of bandwidth for each center frequency is measured.
This procedure requires the test setup and data collected in the Characterizing Power Splitter
Balance section. Characterize the power splitter balance before running this procedure.
Zero the power sensor as described in the Zeroing the Power Sensor section prior to starting this
procedure.
1. Connect the signal generator RF OUT front panel connector to the input terminal of the
power splitter using an SMA (m)-to-SMA (m) cable.
2. Connect splitter output 1 directly to the power sensor input connector using the
SMA (m)-to-N(f) adapter.
3. Connect splitter output 2 to the SMA (f) end of the 6 dB attenuator using a
3.5 mm (m)-to-3.5 mm (m) adapter.
Note The power splitter configuration must match the configuration used in the
Characterizing Power Splitter Balance procedure.