Rohde & Schwarz 1094.0006.50, Руководство по эксплуатации

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CTS55 Description of the Menus
1094.0006.55 9.29 E-7
9.8.3 Config BER Menu
This menu is used to define the tolerances for the bit error rate measurement.
The following values must be defined:
Number of speech
frames
The number of speech frames defines how many bits are used for the bit error measurement. Each
speech frame contains 270 bits allocated to the classes IA, IB and II. This defines how many bits per
class are used for the measurement. They are shown in the Samples column. When defining the
number of frames the test time is defined simultaneously and shown in the field "Time".
Rate Class II
This value defines the percentage for the permissible maximum number of incorrect bits from class II.
The maximum number of incorrect bits is shown in the Events column.
Rate Class IB
This value defines the percentage for the permissible maximum number of incorrect bits from class IB.
The maximum number of incorrect bits is shown in the Events column.
Rate Frames
This value defines the percentage for the permissible maximum number of frames. The maximum
number of incorrect frames is shown in the Events column.
Measurement Mode
The bit error measurement distinguishes between two modes, BER and RBER.
BER:
In this mode all frames are used to calculate the bit errors in classe II and class IB.
RBER:
In this case only the "good" frames in class IB and class II are used. The bad frames are accounted for
in the frame errors. The mobile identifies the bad frames.