Configuring MBSFN Subframes

If you are testing systems that support MBSFN, 3GPP allows you to reserve one or more subframes for multimedia broadcasting.

The MBSFN subframe configuration is part of the "MBSFN Settings" tab of the "Demodulation Settings" dialog box.

MBSFN Subframe... 118 Active... 118 PMCH Present... 118 Modulation...118

MBSFN Subframe

Shows the subframe number that may contain MBSFN data.

Note that 3GPP only allows to turn selected subframes into MBSFN subframes. Depending on the configuration (for example the TDD configuration), different sub- frame numbers are available for MBSFN transmissions.

Active

Turns a subframe into a MBSFN subframe.

If active, the corresponding subframe may contains MBSFN data. Remote command:

CONFigure[:​LTE]:​DL:​MBSFn:​SUBFrame<subframe>:​STATe​ on page 225

PMCH Present

Turns the Physical Multicast Channel (PMCH) on and off.

If you turn on the PMCH, the resource elements of the MBSFN subframe are used by the PMCH.

If you turn off the PMCH, the resource elements of the MBSFN subframe may be used by the PDSCH.

Remote command:

CONFigure[:​LTE]:​DL:​MBSFn:​SUBFrame<subframe>:​PMCH:​STATe​ on page 225

Modulation

Selects the modulation scheme for the MBSFN subframe. Remote command:

CONFigure[:​LTE]:​DL:​MBSFn:​SUBFrame<subframe>:​PMCH:​MODulation​ on page 225

6 Analyzing Measurement Results

The measurement software provides several tools to get more detailed information on the measurement results. The corresponding tools are part of the context menu.

► To access the context menu, click anywhere in the diagram grid with the right mouse button.

Fig. 6-1: Context menu

Using the marker

You can use a marker to get the coordinates of a single point in the diagram area.

► Open the context menu and select the "Marker" menu item.

When the marker is active, the software puts a check mark ( ) in front of the "Marker" menu item.

When you turn it on, the software positions the marker on the trace maximum. After that you can move it around freely to any point of the trace.

In result displays that contain more than one trace (for example EVM vs Carrier), you can select the trace the marker is positioned on (Peak, Minimum or Average trace) with the "Set Marker To" menu item. Note that "Set Marker To" is only available if a marker is already active.

Marker positioning

If you try to put the marker on a coordinate not occupied by the trace, the software puts the marker to the nearest trace maximum (if you place it above the trace) or the near- est trace minimum (if you place it below the trace).

The marker coordinates are displayed in the upper left area of the diagram. The first number shows the vertical position, the second number the horizontal position of the marker including the units.

If you want to reposition the marker on the trace maximum after moving it around, you have to first deactivate the marker and then reactivate it.

To deactivate the marker, open the context menu and reselect the "Marker" menu item.

Note that the marker is not available for all measurements and result displays.

Displaying data points

In result displays that contain a line trace only (for example the Power Spectrum), you can display the data points the trace is based on with the "Show Data Points" menu item. The data points are displayed in addition to the line trace.

Some result displays already contain the data points by default (for example EVM vs Symbol). Note that information might get lost if you turn the data points off in these result displays.

Zooming into the diagram area

If you'd like to see parts of the diagram area in more detail, you can use the zoom.

► Open the context menu and select the "Zoom" menu item. The software opens a submenu with several zooming options.

Fig. 6-2: Zooming options

● Zooming vertically and horizontally (XY)

Click on any point in the diagram area and draw a rectangle with the mouse. The rectangle defines the part of the diagram area you are zooming into.

● Zooming horizontally (X)

Click on any point in the diagram area and define the horizontal section of the dia- gram area you want to zoom into.

● Zooming vertically (Y)

Click on any point in the diagram area and define the vertical section of the dia- gram area you want to zoom into.

● Zooming automatically (Auto XY)

Automatically scales the diagram area so that the complete trace data is visible. Double-clicking on the diagram has the same effect.

● Restoring the default zoom

The software also provides functionality to restore the default zoom each time when the results are refreshed.

► Open the context menu and select the "Default Zoom on Update" menu item.

Panning the trace

If you'd like to see parts of the measurement results that are outside the diagram area, you can move the contents of the diagram area. To move the contents of the diagram area, click anywhere in the diagram area and drag the contents of the diagram area until the parts you'd like to see are visible.

If there are parts of the trace data that are outside the visible display area, the software shows arrows to the right of the diagram area.

The arrows point in the direction where the invisible trace data is. If parts of the trace data is outside the visible area, the arrows are yellow. If all data in a particular direction is outside the visible area, the arrows turn red.

To make sure that the whole trace is always visible, you can use the automatic zoom ("Auto XY") available in the "Zoom" menu.

► Open the context menu and select the "Pan" menu item. The software opens a submenu with several panning options.

Fig. 6-3: Panning options

● Panning vertically and horizontally (XY) Panning is possible in all directions. ● Panning horizontally (X)

Panning is possible to the left and right. ● Panning vertically (Y)

Panning is possible upwards and downwards.

Copying an image to the clipboard

If you want to document measurement results, you can move a copy of them to the clipboard of the operating system.

7 Data Management

For easy handling of special measurement configurations, the software allows you to import or export various kinds of data.