Rohde & Schwarz CMU-K20, Operating Manual

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CMU-K20/K21/K22/K23/K24 Non Signalling: Connection Control
1115.6088.12 4.77 E-11
compensating for the external attenuation or gain. Otherwise it is adapted to the
level closest to the shifted default value.
Error messages If the level defined for RF Level is too high or too low, a window will appear with the
error message "<RF_Level> is out of range. <Permissible max. value> is limit." and
three fields:
Accept Permissible max. value is accepted as generator level
Re-edit The generator level is entered once again
Cancel The last valid input is maintained
When switching over to a different output, the current value of the generator level is
automatically adapted, if required:
•
Towards lower values to the maximum permissible value of the new output
•
Towards higher values to the minimum value of the new output
Remote control
SOURce:RFGenerator:LEVel:UNTimeslot <Level>
RF
Channel
The RF Channel softkey defines the channel number or the frequency of the
generated RF signal.
The assignment of channel numbers and frequencies is unambiguously defined in
the GSM specification for both directions of transmission. Therefore, it is sufficient
to enter only one value (frequency or channel number), the other one is
automatically determined by the CMU.
The following tables contain the channel assignment in the downlink direction (i.e.
from base station/CMU to mobile). Compared to the uplink, all channel frequencies
are shifted by a constant frequency offset depending only on the GSM band
(duplex spacing, see
Table 4-4 on p, 4.70 ). Channel numbers which are not listed
in the tables are not assigned.
Table 4-5 GSM channels in downlink direction
Frequency
/ [MHz]
Channel GSM400
Band
Frequency
/ [MHz]
Channel GSM900
Band
0.2
↓
460.4
---
↓
---
–
0.2
↓
921
---
↓
---
–
460.6
↓
467.4
259
↓
293
GSM 450 band
921.2
↓
925
955
↓
974
R-GSM band
(European railway
netw.)
467.6
↓
488.8
---
↓
---
925.2
↓
934.8
935.0
975
↓
1023
0
E-GSM band
(extended GSM)
489.0
↓
495.8
306
↓
340
GSM 480 band
935.2
↓
959.8
1
↓
124
P-GSM-Band
(primary GSM)
496.0
↓
2700
---
↓
---
–
960
↓
2700
---
↓
---
–
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