Rohde & Schwarz 1094.0006.50, Руководство по эксплуатации

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Windows
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Application CTSgo CTS-K6
1079.2001.01 66 E-3
Note:
For information about how to switch the portable part to service mode contact your manufacturer.
It is very difficult to determine the attenuation to be set for DECT devices empirically. On the one hand,
fixed parts or portable parts have no antenna connectors, which is why antenna couplers must be
used. On the other hand, neither portable parts nor fixed parts signal the power received at the
antenna to the tester as in the case of GSM mobiles. If there are no empirical values for PP or FP or
the coupler, they can only be derived from the two values NTP and BER. The NTP of portable part and
fixed part is typically 24 dBm. If no attenuation is entered on the CTS, the input attenuation can be
approximately determined from the difference between the measured NTP and the typical NTP. The
output attenuation is obtained via the BER, the bit error rate typically increases considerably starting
from a certain receiving level on the DUT. If the sensitivity of the DUT and thus the associated output
level of the CTS is known, the attenuation can again be approximately determined from the difference
between the expected output level and the set output level. In general, large limits should be selected
for the tests for determination of power and bit error rate in order to take into account the inaccurate
determination of the attenuation.
7.5.2 FP Base Settings
This command is used to call the dialog window “FP Base Settings“. Use this dialog window to adapt
the tester to the settings of your fixed part. After your fixed part has been switched to service mode, it
continuously transmits the dummy bearer with a typical RFPI. The CTS can detect the RFPI of the
strongest dummy bearer. If you wish automatic use of this RFPI, click on the respective box. You can
as well enter the RFPI manually in the RFPI field. In this case, make sure that there is no mark in the
respective box. By means of the box “Use detected RFPI in PP Test”, you can automatically use a
detected RFPI in the subsequent portable part test. This is particularly useful if you want to measure
both the fixed part and the portable part, but do not know the RFPI of this set. Enter the MAC identity of
the portable part expected from your fixed part in the PMID field. In the FP test, the CTS behaves like a
portable part. During the test, the fixed part queries this PMID. Normally, fixed parts accept any PMID
in service mode, however, it is also possible that it accepts only certain PMIDs , eg only PMIDs starting
with “Exxxx“. In case of doubts, you can look up the PMID of the portable part in manual CTS mode in
the menu “Call set up” of the Portable Part Test.
Fig.: PP Base settings dialog window