How Do I Make a Power Versus Time Measurement?

How Do I Make a Power Versus Time Measurement?

Last updated: December 2, 2008

This section is only applicable to the lab application and a test application with the required feature license.

The pass/fail result the test set returns indicates whether the entire burst falls within power and timing ranges determined by a point-by-point comparison of the power versus time measurement mask defined in 3GPP TS 05.05 Annex B for either GMSK or EPSK bursts.

Measuring 3GPP TS 51.010 Section 13.3 Power versus Time

This procedure assumes that the BCH parameter for Cell Band is set up correctly for your mobile station and that the appropriate RF IN/OUT Amplitude Offsets have been set to offset loss between the mobile station and the test set. For more details see How Do I Configure the Test Set for My Test System? .

   
NOTE
This measurement procedure assumes that your mobile supports four adjacent uplink timeslots.
   

  1. Press the CALL SETUP key.
  2. Press PDTCH Parameters ( F9 ),
  3. Press the More key (bottom right) to obtain the Call Parms (2 of 2) screen.
  4. Press the Multislot Config ( F7 ) key and select 1 down, 5 up .
  5. Connect the mobile.

  6. Turn the mobile on and wait for Attached in the Active Cell field.
    Note: For mobiles that don't perform a GPRS attach automatically, set the mobile to data mode.

  7. Press the Start Data Connection ( F3 ) key and watch for the Active Cell field changing to Transferring .
  8. Press the Measurement selection key.
  9. Select the Power vs Time measurement.
  10. Press the Power vs Time Setup ( F1 ) key.
  11. Press the Measurement Setup ( F1 ) key.
  12. Set the measurement parameters as needed for your measurement situation, including:
    Burst Capture Range = All; Measurement Timeout = 10 s
  13. Press the Burst Meas Offsets ( F2 ) key and then Burst 1 Meas Offset ( F1 ), Burst 2 Meas Offset ( F2 ), Burst 3 Meas Offset ( F3 ), or Burst 4 Meas Offset ( F4 ) to set up your required time offset values for each burst.

       
    NOTE
    For statistical analysis the test set allows you to set up to 12 time markers. These markers do not define the mask but allow you to obtain measurement results from specified points on the mask. If you want to define your own custom mask, you can do this using the Custom Mask Setup parameters within the Power vs Time Setup menu.

    Offsets are referenced to bit zero in a normal burst. To obtain results from measurement points before bit 0, enter negative offset values.

       

  14. Press the Close Menu ( F6 ) key.

    A typical summary results screen is shown above.

  15. Press the Return ( F6 ) key twice.
  16. Press the Change View ( F2 ) key.
  17. Press the Burst numeric Results ( F2 ) key then Burst 1 Numeric Results ( F1 ), Burst 2 Numeric Results ( F2 ), Burst 3 Numeric Results ( F3 ), or Burst 4 Numeric Results ( F4 ) to view the offset measurement results for each burst.

    A typical numeric measurement results screen for offsets is shown above.

  18. Press the Return ( F6 ) key.
  19. Press the Graph ( F3 ) key to access the full graph view of the four adjacent uplink bursts.

    The structure of the Power versus Time graph menus are slightly different depending on the number of uplink bursts in the multislot configuration. If you require details on how to navigate through the Power versus Time graph menus, see either:

    A typical full graph view of four adjacent uplink bursts is shown above.

    Two types of pass/fail results are provided:

    • An overall measurement pass/fail indicator is positioned in the bottom left corner of the display:
      • The text "Pass" is shown in a green-colored font if the measurement has passed the entire mask.
      • The text "Fail" is shown in a red-colored font if the measurement has failed any part of the mask.
    • Individual pass/fail indicators are provided for each section of the mask. On the display, text labels corresponding to the following sections change color to indicate a pass or fail (green indicates a pass; red indicates a fail):
      • Rise section( Rise )
      • Active (useful) section of Burst 1,2,3,4 ( B1, B2, B3, B4 )
      • Guard period between burst 1 and 2, burst 2 and 3, burst 3 and 4. ( GP1, GP2, GP3 ) (Note: these indicators is only available if you are measuring more than two uplinks)
      • Fall section

    When the Multi-Measurement Count parameter is set to a number greater than 1, it is possible for some, or all of the individual pass/fail indicators to show a pass while the overall pass/fail indicator shows a fail. This is because the individual pass/fail indicators relate to the last of the multi-measurements made, whereas the overall mask pass/fail indicator is an accumulative result from all the multi-measurements made.

    You can zoom in to individual sections of the graph by pressing the Guard Period ( F2 ), and then press Guard Period 1 (F1), Guard Period 2 (F2), or Guard Period 3 ( F3 ) keys. In addition, you can control a marker or change axis values by pressing the Graph Control ( F5 ) key, Marker position ( F2 ).

    A typical graph view of the falling edge of burst 2 is shown above. You can access this view by pressing the Guard Period ( F2 ) key then the Guard Period 2 ( F1 ) key.

    In this case, the marker is turned on and positioned on the falling edge. The marker can be turned on by pressing the Graph Control ( F5 ) key then the Marker Position ( F2 ) key. Set the required marker position using the knob or the numeric entry keys. The signal level at the marker and its position along the x-axis are shown at the top of the display above the graph.

Power versus Time Graph Menus

Related Topics

Power versus Time Measurement Description

Programming a Power versus Time Measurement

Power versus Time Troubleshooting