This topic guides the user through using the preconfigured LTE Clause 8 tests. Because the Clause 8 tests use fading, they require the use of the N5106A PXB Baseband Generator and Channel Simulator, or an external fader. Either selection requires the use of signal generators, one per signal. The external fader, while a selection within the test settings, is not supported by the software. For more information, see the Test Considerations topic.
Test Case Manager also provides the ability to export those waveform settings that are created using a waveform file. The exported settings can be imported for use in the appropriate Signal Studio software. The real-time signal settings are captured and can be viewed using the SCPI Log Viewer. To save the currently download signal settings on the PXB, use the PXB save settings feature (see the PXB online documentation for more information).
Each software setting has a hint (setting information) associated with it. To use the hints, just click on the setting and the hint appears below the settings window.
Some fields within the setting windows are grayed out, while others are not and allow a different setting. The grayed out fields are static settings required by the standards and may change, in accordance with the standards, as active fields within the same window or the Common Settings window are changed.
While making changes, you can monitor the signal changes by viewing the graphic at the bottom of the test settings window. If there is a need to save all of the software settings, this can be done by using the Save As... function to create a state file.
If this is the first time running a Clause 8 test with the required version 14.0 of the Signal Studio for LTE software , perform the Installing Instrument Files tutorial.
If the files are not installed, the software displays a message that the instrument files need updating.
Select a test.
The test shows the number of required signals. Each test signal requires its own signal generator.
If needed, expand Test Cases and any lower level collapsed nodes until the list of tests are displayed.
Select the desired test and view its parameters noting the number of signals.
Each signal requires a separate signal generator.
Setup the instruments and make the connection to eNB.
Configure the instrument(s).
If using an external fader:
Connect the signal generators to the external fader.
Use the process Configuring the Signal Generator to set the properties for each signal generator.
If using a PXB, use the Configuring the PXB process to set the PXB properties, which includes information for signal generators that connect to the PXB.
Click the desired Common Settings node (FDD or TDD) and configure the eNB parameters.
The eNB Type selection determines the grayed out settings in the test selections (test settings window) in accordance to the 3GPP standards, provided that Override Setting in the test settings window is not enabled.
If performing closed loop testing, configure the Closed Loop Test Settings node:
For more information on these settings, see the Closed Loop Test Settings topic.
Click the Closed Loop Test Settings node.
Set the markers by clicking each marker signal property (1, 3, 4) and use the drop-down menu to select the marker signal type.
If needed, click on the properties in the HARQ/TA Settings section, and enter values as needed.
Reselect the test selected in Step 2.
Set the Channel Configuration fields:
In the Fading Simulator field, use the drop down menu to select the instrument.
If PXB is the selection, the signal generators are connected to and controlled by the PXB. They are configured using the software's PXB setting window.
If External Fader is the selection:
it is not controlled by the software
it must provide the AWGN
the software controls the signal generators
If the Number of Rx Ant field is active (not grayed out) and a different entry is needed,click on the displayed value or the drop-down arrow, and make a selection.
The software adjusts the signal generator power levels above those displayed in the test setting window to account for SNR adjustments performed by the PXB. This is done to achieve the correct receive antenna power levels. It uses the this field's value and the Propagation Condition field setting to determine the correct power levels.
If External Fader is the Fading Simulator selection, ensure that the external fader MIMO configuration matches this value.
When using an external fader, it must be able to adjust the SNR to account for the software's signal generator power increase of 3 dB for the 2 Rx antenna selection and 6 dB for the 4 Rx antenna selection. These power increases are not included in the software's displayed signal generator power levels, but are added to the actual output power level.
If the Propagation Condition field is active and a different entry is needed, click on the displayed setting or the drop-down arrow, and make a selection.
If External Fader is the Fading Simulator selection, ensure that the external fader propagation condition matches this setting.
Configure the non-grayed out (active) parameters for the signals:
If using an external fader:
For a TS 36.141 compliant test signal, leave State enabled.
If there is a need to disable State, refer to the State Checkbox Behavior topic for more information.
For each signal, click the Signal Generator field and use the drop-down menu to select an instrument for the current signal.
The drop-down selection menu contains all of the signal generators configured in a previous step. Each signal must use a different signal generator and they must be the configured models shown in the requirements.
Click Channel Bandwidth and set the bandwidth that is appropriate for the eNB under test and as specified by the test in the standards.
Most grayed-out settings for all signals in the test are coupled to the Wanted Signal Channel Bandwidth selection. So a change to the Channel Bandwidth causes most other settings to change in accordance with the 3GPP standards.
Set the remaining parameters as needed or required.
Configure the AWGN based on the Fading Simulator selection:
For the PXB, determine whether to include AWGN by changing the status of the State checkbox.
For the External Fader, configure the AWGN on the fader.
The software does not support the external fader, so the AWGN State checkbox and other properties are grayed out. The external fader must be capable of supplying the AWGN signal.
If there is a need to reconfigure the grayed out parameters, which causes the test to no longer be in compliance with the 3GPP standards, perform the following steps:
Enable the Override Settings by checking the box.
This causes the grayed-out parameters(inactive) to become active so they can be changed.
Modify the settings as needed.
After modifying the settings, if the Override Settings is disabled by unchecking the box, the software resets the grayed out parameters back to their default settings based on the current eNB Type selection in the Common Settings.
Click the Execute button.
If there is a need to stop the signals, click the Stop button.
To restart the signals, click the Execute button, which again performs a download. If the PXB is the fading simulator:
all of the settings are downloaded if Delta Update State is unchecked
only those settings that differ from the previous download are downloaded if Delta Update State is checked