Measuring Time Response of Open Loop Power Control (TROLPC)

Last updated: October 28, 2004

General Procedure

NOTE

Channel power calibration should be performed if the test set is being used for the first time or the operating environment has changed significantly since the last calibration was performed. The channel power calibration also calibrates the access probe power measurement. See Calibrating the Test Set for details.

Connect the mobile station's antenna output to the test set's front panel RF IN/OUT connector and power them on.
Press the blue SHIFT key and then the green Preset key to full reset the test set.
Establish a call with the mobile station with a loopback service option (SO2, SO9, or SO55) and full data rated selected (see How Do I Set Up a Call? ).
Initialize the measurement:
- Press the Measurement selection key.
- Turn the knob to highlight the Time Response of Open Loop Power Control measurement and press the knob.
  
  NOTE
  
  If any measurements are open during initiation of a TROLPC, the test set will automatically close them and display an error message indicating the last measurement that was closed.

Press the Time Response of OLPC Setup ( F1 ) key to access the Time Response of OLPC Setup menu.
Set the measurement parameters as needed for your measurement situation by using the knob and DATA ENTRY keys. Press the Close Menu ( F6 ) key to close the Setup window.
Measuring TROLPC:
- Select Start Meas Up ( F2 ), which automatically increases Cell Power by 20 dB and captures the resulting mobile station output power for 100 ms, or
- Select Start Meas Down ( F3 ) which automatically decreases Cell Power by 20 dB and captures the resulting mobile station output power for 100 ms.
- You may also select START SINGLE to start the measurement. The cell power will increase by 20 dB if Start Meas Up ( F2 ) was last performed (or if the test set is in a preset state), or decrease by 20 dB if Start Meas Down ( F3 ) was last performed.
- Select Marker ( F4 ) and turn the knob to display power at points along the mobile station output power trace. If the test failed, next to the word "Fail," the first data point at which the test failed is displayed.
NOTE

As specified by TIA/EIA 98-E test standards, mobile station power level change is expressed in absolute terms. The delta expressions above the display indicate the direction of power changes.

After finishing the measurements:
- If desired, turn the measurement off by pressing the Measurement selection key, selecting Time Response of Open Loop Power Control , then Close Measurement ( F4 ).

Testing 4.4.2 Time Response of Open Loop Power Control

Definition: Following a step change in the mean input power, the mean output power of the mobile station changes as a result of the open loop power control. This test measures the open loop power control time response to a step change in the mean input power.

The following test procedure assumes that the mobile station supports Band Class 1 (US PCS) and only demonstrates the Test 1. You should change the settings as specified for other tests. Unless otherwise stated, leave all parameter settings to the defaults.

Connect the mobile station's antenna output to the test set's front panel RF IN/OUT connector and power them on.
Press the blue SHIFT and then the green Preset key to full reset the test set.
Establish a call with the following parameter settings (some settings may change as specified for each test).
- Press CALL SETUP to access Call Parms and Call Control menus.
- Set Cell Band ( F8 on the Call Parms 1 of 3 ) to US PCS .
- Set Radio Config ( F11 on the Call Parms 1 of 3 ) to (Fwd1, Rvs1) .
- Select FCH Service Option Setup ( F12 ) (Call Parms 1 of 3) , set Service Option for Fwd1, Rvs1 to SO2 (Loopback) .
- Set Traffic Data Rate ( F12 on the Call Parms 2 of 3 ) to Full .
- Press Originate Call ( F3 ) to initiate a call. Verify that the Connected is in the Active Cell status field.
Set Cell Power (Î _or ) to -60 dBm/1.23 MHz ( F7 on the Call Parms 1 of 3 ).
Set Rvs Power Ctrl to Alternating bits ( F7 on the Call Parms 2 of 3 menu) to send alternating '0' and '1' power control bits on the Forward Traffic Channel.
Press the Measurement selection key and select the Time Response of Open Loop Power Control measurement.
Press the Time Response of OLPC Setup ( F1 ) key to access the Time Response of OLPC Setup menu.
- Set F-FCH/Traffic Level to -7.4 dB.
- Press Close Menu ( F6 ).
Measure the TROLPC and observe the Pass/Fail result:
- Select Start Meas Up ( F2 ) which automatically increases Cell Power by 20 dB and captures the resulting mobile station output power for 100 ms, observe that the cell power transitions to -40 dBm/1.23 MHz and note the pass/fail result.
- Select Start Meas Down ( F3 ) which automatically decreases Cell Power by 20 dB and captures the resulting mobile station output power for 100 ms, observe that the cell power transitions to -60 dBm/1.23 MHz and note the pass/fail result.
- Select Start Meas Down ( F3 ) which automatically decreases Cell Power by 20 dB and captures the resulting mobile station output power for 100 ms, observe that the cell power transitions to -80 dBm/1.23 MHz and note the pass/fail result.
- Select Start Meas Up ( F2 ) which automatically increases Cell Power by 20 dB and captures the resulting mobile station output power for 100 ms, observe that the cell power transitions to -60 dBm/1.23 MHz), and note the pass/fail result.
After finishing the measurements:
- If desired, turn the measurement off by pressing the Measurement selection key, selecting Time Response of Open Loop Power Control , then Close Measurement ( F4 ).

Measuring Time Response of Open Loop Power Control (TROLPC)

General Procedure

Testing 4.4.2 Time Response of Open Loop Power Control

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