Rohde & Schwarz CMU-K20, Руководство по эксплуатации

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Signalling: Connection Control
CMU-K20/K21/K22/K23/K24
1115.6088.12 4.172 E-12
digital/analog conversion directly to the analog output. This signal is
used for external calibration of the analog input paths.
Codec Cal
The CMU sends and receives speech frames that are routed to the
internal speech codec (option CMU-B52). Analog signals are
provided via the
SPEECH
connector at the front panel of the
instrument. The analog input signal at connector
SPEECH
is not
amplified. The CMU sends a close loop message to the mobile
station to activate an internal test loop.
Receiver Quality
measurements require a pseudo random bit sequence to be
transmitted on the traffic channel. This sequence can be set independently as
Bit
Stream BER(
see p. 4.131 ); the bit stream set in the
Network
tab is not valid for
Receiver Quality
measurements
.
Note: Some Bit Stream settings require a particular configuration of the
instrument. In particular, all settings after Echo (i.e. Handset, Handset
Low, Decoder Cal., Encoder Cal, Codec Cal.) are not available if one
of the following conditions is true:
•
The speech codec (option CMU-B52) is not installed.
•
One of the AMR traffic modes and DTX (MS) mode is active
simultaneously.
•
One of the full or half rate data traffic modes is active.
•
The
B52 Mode
(see p.
4.174
) is set to
Multislot Support.
Remote control
CONFigure:NETWork[:CSWitched]:SMODe:BITStream
PROCedure:NETWork[:CSWitched]:SMODe:BITStream
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