Possible Setup Issues
If a GSM BER measurement or GSM FBER measurement is started while the IFER measurement is in progress, the IFER measurement will close.
A GSM voice call must be originated from the mobile station or the test set before an IFER measurement can begin.
In order to run the AMR IFER measurement, the Logical Speech Channel must be set to on of the AMR related speech channels, wither AFS (Adaptive Full) or AHS (Adaptive Half).
An IFER measurement can only be made when the Operating Mode is set to
Active Cel
l and the
Serving Cell
is
GSM
,
GPRS
, or
EGPRS
and when the Connection Type is
Auto
or when the Operating Mode is GSM BCH+TCH. If the connection type is not Auto, any origination from the test set will be a data connection. AMR does not work for data connections.
The mobile station must be capable of performing a Loopback Type I, otherwise the measurement results cannot be guaranteed to be accurate. The measurement is always available regardless of the capabilities of the mobile station.
When the IFER measurement activates, it overrides the setting for the current codec. When the IFER measurement is deactivated, the current codec is set on the downlink traffic channel. Any changes to the current codec set and/or thresholds that are made during the IFER measurement are ignored until the next call is initiated.
When configuring AMR parameters through the front panel under the Codec Setup menu,
Apply Changes
(
F5
) must be pressed to save the new configuration.
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.