When the PXB is powered on, it displays the "1 Channel Generate" configuration, the most basic configuration in the Configuration Browser as the default. The PXB will only display configurations that the PXB’s baseband and I/O card option structure will support.
To turn on the PXB, press the front panel power hardkey.
Allow the PXB to boot and display the firmware.
Select the "Generate and Fade 1 Channel" configuration from the Configuration Browser.
The block diagram for this selected configuration is displayed on the Block Diagram tab.
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 N5182A MXG For this example, we are calling out the Agilent MXG as the signal generator, however the Agilent E4438C ESG signal generator will also work well for the example.signal generator as the external instrument.
The registration process only needs to be performed once per instrument. If the instrument that you plan to use is already registered (see step 1 below), you may skip to the next section, "3. Assign External Instruments."
For this example, an Agilent N5182A MXG signal generator is being registered.
Click the External
Instrument Table tab to display the External Instrument Table. 
Illustration…
This illustration shows the External Instrument Table with that has been populated with several external instruments used with the PXB.
The External Instrument Table displays the external instruments that are currently registered with the PXB firmware. External instruments that can be registered are:
N5182A MXG Signal Generators (used at the output of the PXB)
E4438C ESG Signal Generators (used at the output of the PXB)
N5102A Digital Signal Interface Module (DSIM) (used at the input or output of the PXB)
N9020A MXA Signal Analyzer (used at the input of the PXB for (ext in) configurations)
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.
Select the Add
button to start the registration process. This displays the Register External Instrument
dialog box.
Illustration…
In the Name text box, enter "MXG1" or another name to describe your signal generator. For the remainder of this example, the signal generator is referred to "MXG1".
In the Family drop down list, select instrument family that describes the instrument's family. In this case, select MXG.
In the Visa Interface drop down list, select the interface that the PXB will use to communicate with the instrument (TCPIP0 = LAN or GPIB0 = GPIB).
In the Address text box, enter the address specific to the instrument that you are registering.
| As you proceed through this step, use the actual LAN address for your instrument. |
Click the OK button to complete the registration. The External Instrument Table should now show the instrument that you just registered (an MXG, in this case).
Click the Block Diagram tab to return to the configuration block diagram that was originally displayed.
External Instruments must be selected and set up for the PXB.
In the Configuration Browser, ensure that the Generate and Fade 1 Channel configuration is selected.
Review the block diagram.
You will see a User File block, a BBG 1 block, a Fader1 block and an I/O1 Port A1 block (this block is an output which connects to a signal generator). You will also see an (Unassigned) block which represents an unassigned block for an external instrument (the signal generator).
On the unassigned external instrument, click the
button to display
the Assign
External Instrument dialog box.
In the Assign
area of the Assign External Instrument
dialog box, select the MXG signal generator that you registered previously
from the Instrument drop down
list.
Illustration…
In the To area, leave the I/O Port Name field set to the default selection. Ensure I/O Port Type field is set to Digital.
The I/O Port Name field allows you to select any available I/O port.
The I/O Port Type field allows you to select from two types of I/O port connections for the ESG or MXG signal generators.
Digital connects the PXB to the signal generator via the LVDS digital bus cable.
Analog connects the PXB to the signal generator using analog outputs with individual cables for the analog I/Q connections.
Click OK to return to the block diagram. Note that the external instrument block now displays the selected signal generator.
Connect the PXB to the signal generator as shown.
Illustration…
Waveform (User File) blocks enable the user to select the signal creation source from an arbitrary waveform file (User File) or from a Signal Studio real-time option. In this example, we will select an arbitrary waveform file.
In the waveform block, click the button to display the Assign
Waveform Source
dialog box.
Select ARB as the waveform type and User File as the waveform format.
Click OK to return to the block diagram. Note that the external instrument block now displays the selected signal generator.
Select the Load Configuration button to load the settings for each of the configuration blocks.
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 listed in the Settings Browser. You are now able to view and edit the setting for each block. Now we will set up the baseband generator block and download a factory-loaded waveform to play.
Open the waveform settings for User File1. This can be done in one of two ways:
Select the User File1 block in the block diagram
Select the User File1 label in the Settings Browser
Select Waveform
Source Name to display the ellipsis 
button at the right edge of its settings cell. Then
select the ellipsis button to display the Open
File dialog box.
Select a waveform file from the default folder. (you will download it to baseband generator memory in a later step)
The default folder, C:\<Program Files for Win XP><Program Files (x86) for Win 7>\Agilent\PXB\FactoryDefaultWaveforms, contains several factory default waveforms that you can choose. Refer to Factory Default Waveform Files for a description of these waveforms.
If you have already loaded other waveform files on the PXB, you can navigate to the folder it was saved in using the Open File dialog box.
In the Settings Browser or the block diagram, open the baseband generator settings for BBG 1.
Notice the four tabs that are displayed: General
Settings, Marker Generation,
Power Calibration Settings, and
Power Calibration Graphics
Illustration…
Selecting a tab label displays the tab’s settings. The General Settings are similar to those found in traditional signal generator, such as, Sample Rate, Trigger Delay, and Baseband Frequency Offset, allowing you to have a frequency offset in the baseband which offsets the carrier from the signal frequency.
Select the Marker Generation tab to review this tab's settings.
Select the Power Calibration Settings tab to review this tab's settings. The Power Calibration Graphics tab provides a graphical description of some of the power control settings.
Select the Block Diagram button to return to the block diagram.
Select the Download Panel button to display the Download Table.
The table displays the selected waveform source file as Waveform 1. Notice that Waveform Status is ”Out-of-Date” and Download Status is ”Not Started,” which indicates that the waveform has not been loaded to the baseband generator yet.
Select the Start button to download the designated waveform from the PXB hard drive to the playback memory the baseband generator.
Notice that, once the waveform has been downloaded, Waveform Status is displayed as ”Up-to-Date” and Download Status is displayed as ”Completed.”
Return to the block diagram.
Navigating the Fader block is slightly different and a little more complex than other configuration blocks. You will see that fading has two areas for setup: Master Setup and Fader Paths. For this reason, the fading procedure is organized into three parts:
The Fader block has two areas: Master Setup and Fader Paths. The Master Setup interface is similar to the other block interfaces that we have explored. The Fader Paths interface is a table that defines each of the fading paths.
Open the Master Setup settings for Fader1
by selecting Master Setup 1 from
the Settings Browser. If necessary,
expand the settings beneath the Fading
label by selecting the 
icon. Note that the Fader
Paths label is beneath the Master Setup label as shown.
Illustration…
Notice that Master Setup has a Fader Setup tab. If you are using a
configuration that has a Master Setup
with more than one Fader block, such as 2 Channel Generate and Fade, there
is also a Correlation tab (highlighted
in the illustration).
Illustration…
Note that when a configuration's Master
Setup has more than one Fader block, multiple Fader settings are
displayed on the Fader Setup tab
as well. This area is also highlighted in the illustration.
With the Fader Setup tab selected, review this tab's settings.
When you use a configuration that has a Master Setup with more than one Fader block, you can access the Correlation tab to edit the correlation table defining the degree of correlation for the paths between the Fader blocks.
After reviewing the Master Setup, open the Fader1 Paths table by selecting the Fader1 Paths label in the Settings Browser.
Review the Fader1 Paths table.
Illustration…
By scrolling down, you will notice that there are 24 rows representing each of the PXB's maximum of 24 paths. By scrolling across the table from left to right, you can see there are a variety of settings used to define each path. You can add or subtract settings columns by clicking the Columns button at the top of the Fader Paths table
Setting up the Fader block can be as easy as selecting the appropriate fading model that you are using from a list of standard technologies.
With Fading expanded in the Settings Browser, select Master Setup 1 to view the Master Setup settings.
Select Fader 1
Channel Model to display the drop-down 
button at the right edge of its settings
cell. Then select the drop-down button to display a list of the available
fading channel models.
For this example of the Fader
1 Channel Model setting, select W-CDMA,
then select Base Station, and
then select Moving Propagation.
Illustration…
As you can see, there are many channel models included in the PXB to choose from.
Once you have selected Moving
Propagation, ensure that Fader1
Paths is displayed below Master
Setup 1 in the Settings Browser.
If not, expand the Master Setup 1
using the icon to display it.
Select Fader 1
Paths to display the number of paths, the fading type, the spectral
shape, the delay values, and a variety of other variables which are all
based on the standard for the selected channel model.
Illustration…
These channel model variables are displayed in tabular format This table is complex and can list approximately 20 variables across the ”X-axis”, although just a few can be seen without scrolling. All of the available paths are listed along the ”Y-axis”.
Select the Master Setup 1 from the Settings Browser to return to the Fader Setup settings.
Having just set up the Fader block by selecting a channel model from a list of standard technologies, we will look at using one of these standards and customizing it to fit any specific fading needs you may have.
Change the Fader 1 Channel Model setting from the previous selected W-CDMA, Base Station, Moving Propagation standard by selecting Mobile WiMAX, then Vehicular A(60 kph) in the drop-down list, as in step 3 of the Basic Fading Setup procedure above.
Select Fader 1 Paths to display the number of paths and all of the other variables for the selected channel model.
It’s easy to see that this new standard has different properties than the one we looked at previously.
Select the Enabled check boxes for paths 7 and 8 so they are both checked. You have just added two paths to the channel model.
For paths 7 and 8, click the Fading Type drop-down button and select Suzuki for each path.
Enter "17.50 dB"
in the Loss column for path 7
and enter "22 dB" in the Loss
column for path 8. These are both arbitrary values. You could enter a
meaningful value for your test requirements.
Illustration…
We have just added channels and changed settings to show that you can customize your Fader setup by manually adjusting the channel properties to meet your specific needs. These types of changes may be made to any of the attributes of the standard settings definitions. You have two different ways to set up fading: From Standard and Custom.
Return to the block diagram.
The output I/O port is used as the output interface to an external instrument (either a signal generator or an N5102A Digital Signal Interface Module) at the output of the PXB. The output I/O Block has its own settings that are customized for the output.
Open the I/O Port settings for I/O1 Port A1. This can be done in one of two ways:
Select the I/O1 Port A1 block in the block diagram
Select the I/O1 Port A1 label in the Settings Browser
Notice the four tabs that are displayed: General
Settings, AWGN Settings,
Marker Selection, and AWGN
Graphics.
Illustration…
We are not going to make any changes to these settings right now but merely do a quick review on how each of the tabs can influence the output of the PXB.
Review the General Settings tab.
The General Settings tab provides information about the I/O port and can be used to make changes to the I/O port. You will notice that the Mode setting is a read-only entry that displays Output indicating that this I/O port is being used as an output I/O.
Select the AWGN Settings tab to review this tab's settings. This tab is used to add and control Additive White Gaussian Noise (AWGN) to the output signal at the I/O port. The AWGN Graphics tab provides a graphical description of some of the AWGN settings.
Select the Marker Settings tab to review this tab's settings.
Markers generated in the output I/O block, are based on the signals that arrive at the output I/O block. Markers that are generated from an output I/O block that is receiving a single-input waveform, are merged with the waveform as it was received at the output I/O block. Therefore, if the original waveform has had fading or interference added, the degraded waveform is used to generate these markers. This is important to note because dynamic markers use the values of the waveform samples to determine when markers are generated.
Any output I/O markers will override markers previously embedded in the original waveform file or generated by a user-created marker file or baseband generator block.
Return to the block diagram.
Each external instrument provides for basic control of the instrument via the N5106A. Reviewing user interface will show you that the N5106A has a number of settings that will allow you control over your signal generator.
Open the MXG settings for MXG1, the signal generator that we have assigned as the external instrument for this configuration. This can be done in one of two ways:
Select the MXG1 block in the block diagram
Select the MXG1 label in the Settings Browser
Notice that
this external instrument has two tabs that are displayed: General
Settings and Marker Routing
Illustration…
We are not going to make any changes to these settings right now but merely do a quick review on how each of the tabs can be used to control the signal generator from the PXB.
Review the General Settings tab.
The General Settings tab
is comprised of three categories:
Basic Settings which provides control of very basic signal generator settings.
ALC Settings which provides control of the signal generator’s Automatic Level Control (ALC) and attenuator circuitry.
Power Search Settings which provides control of the signal generator’s power search function when a power calibration is performed.
Select the Marker Routing tab to review this tab's settings. This tab allows you to set up the markers to control the Pulse/RF Blanking and the ALC Hold features.
Return to the block diagram.
Once the PXB configuration is set to meet your test needs, you can simply calibrate the system power and play the waveform from the BB Gen block through the I/O block to the connected signal generator via the digital bus.
Power calibration occurs automatically by default. If
you want manual control of power calibration, select Maunal
in the System > Calibration > Power
Calibration menu, then select the Calibrate
Power button to perform the power calibration based on the baseband
generator block's Power Control Settings and the output I/O block's AWGN
Settings.
More information
| You cannot perform a Calibrate Power operation unless the selected waveform in the Download Panel has both "Up-to-Date" and "Completed" waveform status. |
Select the Play button to start playing the waveform from BB Gen1.
When you wish to stop playing the waveform, select the Stop button.
To save the configuration and its settings, select Save from the File menu.
To recall the configuration and its settings, select Recall from the File menu.
