How Do I Make Soft/Softer Handoff Tests Regarding T_Drop/T_TDrop?

Last updated: October 28, 2004

This section is only applicable to the lab application.

With this test setup, the mobile station is expected to send a Pilot Strength Measurement Message (PSMM) to the base station when the Cell 2 Pilot Strength falls below the T_Drop threshold (32 is the default, indicating - 16 dB relative to the total RF power) for the period of time specified by T_TDrop (3 is the default, indicating 4 seconds), and the Cell 2 pilot (Pilot Offset 36) is flagged as a "To Drop" (see T_Drop/T_TDrop Behavior for description). The Cell 2 pilot is removed from the Active set of pilots when the soft handoff is ended.

1. Establish a call (see A. Establish a call. ) with the Cell 1 Power set to -55 dBm/1.23 MHz.
2. Set the Soft Handoff Parameters to the defaults (see B. Set Up Soft/Softer Handoff Parameters ) and make sure the Soft Handoff ( F4 ) is Off .
      

   NOTE

   The F-Pilot Level field is corresponding to the Pilot Ec/Ior parameter in the TIA/EIA-98E standard and the F-FCH/Traffic Level field corresponding to the Traffic Ec/Ior parameter.

   ---

      

3. Clear the Mobile Station Reported Pilot Level Information display (see E. Clear Mobile Pilot Report ).
4. Set the Cell 2 Power ( F1 ) to -52 dBm/1.23 MHz and set the AWGN Power ( F3 ) to Off (see C. Set the Cell 2 Power and AWGN Power ). This causes the Cell 2 pilot level to exceed the T_COMP threshold.
      

   NOTE

   The Cell Power field is corresponding to the Î _or parameter in the TIA/EIA-98E standard and the AWGN Power field corresponding to the I _oc parameter.

   ---

      

5. Press the Soft Handoff (F4 ) key and set the Soft Handoff State to On .
6. Observe the Mobile Station Reported Level Information display. Both Cell 1 and Cell 2 pilots should be Active and current Handoff Status is Soft. This indicates that a soft handoff has been established with Cell 2 and Cell 1 as active set pilot and traffic channels.
   
7. Press the Cell 2 Power ( F1 ), slowly turn the knob until it decreases to -66 dBm/1.23 MHz (in this example). This causes the Cell 2 pilot level to below the T_Drop threshold.
8. Wait 5 seconds. Observe the Mobile Station Reported Level Information display. The mobile station should have sent a Pilot Strength Measurement Message (PSMM) to the base station since the Cell 2 Pilot Strength falls below the T_Drop threshold for the period of time specified by T_TDrop. The test set flags the Cell 2 pilot (Pilot Offset 36) as a "To Drop" when the reported Pilot Strength is below T_Drop.

   If the Generated Pilot Level Information display, which shows the actual pilot strength and PN offset transmitted by the test set, indicates that the Cell 2 Pilot Strength falls below T_Drop threshold (32, -16 dB) and the mobile station has not sent a PSMM, a failure condition may exist with the mobile station. Send the pilot measurement request by pressing the Send Pilot Meas Request ( F5 ) key (see F. Send Pilot Meas Request ) and compare the mobile reported pilot information to the actual information in the Generated Pilot Level Information display.

   
9. End the soft handoff. Press the Soft Handoff (F4 ) key and set the Soft Handoff State to Off .
10. Observe the Mobile Station Reported Level Information display. The Cell 2 pilots should be removed from the display and current Handoff Status is None. This indicates that a soft handoff has ended and the connection only with Cell 1 as active set pilot and traffic channel.