Rohde & Schwarz CMU-K20, Operating Manual

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Menu Structure CMU-K20/-K21/-K22/-K23/-K24
1115.6088.12 3.2 E-10
erably. The test signal may be inside or outside the designated GSM channel
range.
Normal burst signals are generated and analyzed. Various transmitter quality
measurements (burst power versus time in one or several timeslots, average
burst power in subsequent timeslots or frames, phase and frequency errors,
error vector magnitude, I/Q imbalance and origin offset in the constellation dia-
gram, adjacent channel power due to switching and due to modulation) can be
performed. GMSK and 8PSK-modulated signals are supported. The measure-
ment may be triggered by an additional external signal.
Signalling Mode In the Signalling mode, the CMU starts to transmit a signal using a control chan-
nel. In subsequent steps, the mobile synchronizes to the control channel, de-
codes the information transmitted, and performs a location update so that a call
can be delivered from either the mobile or the CMU.
The CMU is able to configure a broad range of network parameters and to de-
termine the parameters characterizing the mobile. Measurements of the burst
power versus time in one or several consecutive timeslots, of the average burst
power in consecutive timeslots or frames, the modulation parameters (phase
and frequency errors, I/Q imbalance and origin offset in the constellation dia-
gram), the adjacent channel power due to switching and due to modulation, and
of the bit error rate can be performed for normal bursts and access bursts.
GMSK and 8PSK-modulated signals are supported.
If option CMU-K42 is installed in addition, the CMU can also establish a TBF
connection to a mobile station operating in packet-data (GPRS) mode. Single-
slot and multislot measurements can be done in the GPRS test mode.
Symbols for
Signalling Mode
and State The signalling mode and state is indicated to the left of the operating mode in
each main menu and graphical measurement menu (see chapter 3 of CMU op-
erating manual). The following symbols occur in function group
GSM400/850/900/1800/1900-MS:
Non signalling mode; module tests
Signalling mode, Signal Off
Signalling mode, Signal On or GPRS Idle (symbol blinks)
Signalling mode, Synchronized or GPRS Attached
Signalling mode, Alerting or GPRS Connecting TBF (symbol blinks)
Signalling mode, Call Established or GPRS TBC Established
Configurations
The CMU offers a wide range of settings for the RF signal generator and analyzer, the signalling proce-
dures, and the individual measurements. Configurations can be set either for the whole function group
(Connection Control) or for a particular measurement.
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