Rohde & Schwarz 1094.0006.50, Руководство по эксплуатации

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Test Sequence CTS55
1094.0006.55 4.12 E-6
4.11 10th Step - Bit Error Rate
The measurement is performed at the sensitivity level defined for the mobile type. The measurement is
made by sending bits to the mobile. The mobile echoes the bits back to the CTS, where the original bits
are compared with those echoed back. The difference between the two values is expressed as a
percentage.
The BER measurement has three results:
Tolerance (wide)
RBER (residual bit error) of the Class II bits 5.2%
RBER (residual bit error) of the Class Ib bits 0.8%
FER (Frame erasure rate) 2.0%
For the BER measurement 250 speech frames are used.
RBER Class Ib and FER are subject to the
α
-evaluation; i.e, with high RBER Class Ib and low FER or
with low RBER Class Ib and high FER both are evaluated "pass".
4.12 Steps 11 - 14 - Measurements on the second channel
The measurement in the steps 7 to 10 are done on the first channel defined for the Autotest. In the
steps 11 to 14 the same measurement are carried out again but on the second channel defined for the
Autotest. The tolerances are the same as for the measurements on the first channel.
4.13 15th Step – Handover or Network Release
During this step the CTS will either perform a network release or attempt a handover to the new band.
The step action is determined by the settings within the „Handover Details“ menu. If the instrument is
configured for Dual Band handover, then the CTS will attempt a handover at this point.
If the instrument is not configured for Dual Band handover, then the CTS will attempt a network release
prior to concluding the test sequence. Following a correct close down of the speech link, the test is
concluded with a "
9
" if successful or a "f" if not.
If a handover is attempted and succeeds, then the CTS will perform an echo test in the new band. After
completion of the echo test, steps 4.8 – 4.12 will be attempted in the new band. Provided that each step
in the second band reaches a measured conclusion, then a further handover back to the original band
will be attempted.
The final step of the two band autotest sequence is the same as a single band test and is to perform a
network release.
Hint:
If a single band mobile is to be tested, then it is necessary to disable any handover steps being
attempted. This can be achieved from the general “Config – Select” Menu, within "Handover Details" by
changing the “Network Switch” to the single band setting.
If a single band mobile is tested with an instrument that has been configured to support handover, then
Autotest will fail the handover step and ultimately fail the complete test."
At the end of the test cycle, an overall test result is obtained on the last line of the display. More detailed
results and measurements can now be output on a printer by pressing the "Print Report" key if the
option CTS-B5 is installed.