Frame Error Rate (Receiver Measurements)

Chapter 4, Troubleshooting

Errors While Attempting Measurements

Problem:

If your Test System is not set up correctly for receiver tests, you may see erroneous results (extremely high FER or the inability to return a measurement) on the tool you use for displaying the Frame Error Rate calculated by the base station.

The error can occur while using the following menu screen:

•CDMA Generator Menu Selection

Possible causes and solutions:

1Missing an Even-Second clock timing signal.

You must have access to the Even-Second clock signal from the base station to achieve proper correlation to the CDMA signal. Verify that the signal is accessible and make sure that it is connected to the EVEN SECOND/SYNC IN port on front of the Cellular Adapter. To verify your Even-Second clock, see "Check Even-Second Clock" on page 46.

2Test System timebase reference not connected.

Verify that you have access to the base station’s reference timebase signal (typically 19.6608 MHz). The reference should be connected to the SYNTH REF IN port on the rear of the Cellular Adapter. If configured correctly, the REF UNLOCK indicator on the Cellular Adapter should not be on.

3Missing or faulty connections from the PCS Interface output to the receiver inputs of the base station.

Check to see that the RF IN/OUT port of the PCS Interface is connected to the receiver test port of the base station being tested.

4Incorrect Base Station Channel entry.

The Software tunes the CDMA Generator to a receive frequency based on your entry for Base Station Channel. The entry must match the channel your base station is set to receive on. Verify the channel number entry in the Base Station Channel field on the main menu screen. If you want to verify the frequency the Generator is set to, see the Generator Frequency setting at the bottom of the main menu screen.

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