Testing a Mobile for Enhanced Full Rate Speech and Half Rate Speech Channel Modes
Last updated: May 8, 2002
This test is
not
applicable to GPRS.
The channel mode function allows you to command a mobile to switch between full rate speech, enhanced full rate speech and half rate speech either before a call is originated, or during a call connected state with any or all of the supported measurements running. In half rate speech mode you can also set the half rate sub channel.
The following measurements are supported in enhanced full rate and half rate speech modes:
-
Analog Audio (AAUDio)
-
Bit Error Rate (BERRor)
-
Fast Bit Error Rate (FBERror) (only supported in enhanced full rate)
-
Dynamic Power (DPOWer)
-
I/Q Tuning (IQTuning)
-
Output RF Spectrum (ORFSpectrum)
-
Phase and Frequency Error (PFERror)
-
Power versus Time (PVTime)
-
Transmitter Power (TXPower)
You can initiate a Decoded Audio (DAUDio) measurement in enhanced full rate and half rate speech modes. However, this measurement is not supported in this channel mode and the integrity indicator will report that the results are questionable (see
Decoded Audio Troubleshooting
).
If you change the channel mode when no call is connected, the mobile is requested to go into the selected channel mode the next time a mobile originated or mobile terminated call is initiated.
If you change the channel mode when a call is connected, the mobile is requested to go into the selected channel mode immediately.
The channel mode should only be changed when the test set is in active cell operating mode, not test operating mode.
GSM Phase 1 mobiles are not required to support enhanced full rate or half rate speech vocoders. Therefore, the behavior of a GSM Phase 1 mobile which does support this may be manufacturer dependent when used with the channel mode function.
If you switch the channel mode between the differerent speech modes when the downlink speech source is set to Echo (see
CALL:TCHannel:DOWNlink:SPEech
), you may hear momentary unpleasant audio bursts from the mobile.
