1-Channel Signal Capture Configuration

 

 

1. Basic Introduction and Turn-On

ClosedDetailed Steps

When the PXB is powered on, it displays the "1 Channel Generate" configuration, the most basic configuration in the Configuration Browser as the default. This configuration is available to all PXBs. The PXB will only display configurations that the PXB’s baseband and I/O card option structure will support.

 

2. Register External Instruments

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The PXB is designed to use a variety of external instruments to provide external inputs or received the output of the PXB. These external instruments can be controlled by the PXB firmware; however, the external instruments must be registered within the firmware prior to being available for use.

This example setup procedure uses the N9020A MXA signal analyzer as the external instrument.

The registration process only needs to be performed once per instrument. If all of the instruments that you plan to use are already registered (see step 1), you may skip to the next section, "3. Assign External Instruments."

For this example, an Agilent N9020A MXA signal analyzer is being registered.

The External Instrument Table displays the external instruments that are currently registered with the PXB firmware. External instruments that can be registered are:

The table displays the name, instrument type, address, and I/O Port (this is discussed more in the next step) of each registered external instrument. If no instruments are displayed in the table, then no instruments are currently registered.

As you proceed through this step, use the actual addresses for your instruments.

 

 

3. Assign External Instruments and Load Configuration

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External instruments must be selected and set up for the PXB.

    1. In the Configuration Browser, ensure that the Signal Capture 1Ch configuration is selected.

    2. Review the block diagram.

You will also see an (Unassigned) block representing the external instrument, an I/O1 Port A1 block representing the I/O interface between the external instrument and the PXB, and a Signal Capture1 block for capturing signal data to a waveform file.

 

4. Set Up Signal Analyzer

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When the configuration is loaded, the Settings Browser replaces the Configuration Browser in the left panel of the user interface. Each block from the block diagram is also listed in the Settings Browser. You are now able to view and edit the settings for each block. Now we will set up the signal analyzer.

The PXB user interface provides basic control of the signal analyzer via the LAN/GPIB interface. The PXB and signal analyzer are also connected via the digital bus for waveform data transfer. Optimizing the MXA provides a procedure and discussion of how to maximize the MXA's dynamic range for use as an input to the PXB.

Note that there are also buttons that will preset the signal analyzer, update the PXB with the signal analyzer settings, and level the signal analyzer's input.

 

5. Set Up Input I/O Port

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Now we will set up the input I/O block. This block is the interface from the signal analyzer as it connects with the PXB.

 

6. Set Up Signal Capture Block

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Signal capture capability enables you to save external input signals to a waveform (.bin) file that you can later play back for testing or analysis.

The .bin files saved are unencrypted and can be used with any Agilent signal generators for playback, including the PXB. You can later analyze signals captured and saved as .bin files using the VSA software, but it requires byte swapping. You can also import them into Matlab; however, the files require some reformatting. See Understanding Binary Formatted Waveform Data for information on the supported I/Q waveform format.  

The captured files can be analyzed by the VSA software as a recording but it requires byte swapping.  

The captured files can also be imported into Matlab but the user has to reformat the files themselves.

Set up the capture block.

 

7. Play Waveform

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Once the PXB configuration is set to meet your test needs, you can simply calibrate the system power and play the signal from the connected signal analyzer via its digital bus through the input I/O block, and capture the incoming signal using the Play button as the trigger.