Diagram Types - OPTICOM OPERA - V 3.5 User Manual

6.6.4 Diagram Types

Waveforms and
VAD Parameters
C H A P T E R 6 : T E L E P H O N Y
T E S T I N G
•
Due to the complex and iterative time alignment algorithm, the data are all
processed in one frame. There is no history through which the user can
scroll for an analysis of the signals. The input data are processed as if they
were exactly one large frame.
Figure 6.21 shows the result diagrams available for PESQ. Our PESQ
implementation offers much more then just voice quality testing. A partial side
effect is a detailed analysis of VAD behaviour, jitter buffer adaptation or
AGC/ALC tests.
Figure 6.21:
Result types available for PESQ
The "Waveforms and VAD Parameters" display of PESQ as shown in
6.22 differs significantly from the Timesignal displays of the other algorithms,
since it shows the entire waveforms in one diagram instead of the framewise
displays of the other algorithms. Within this diagram you can plot the following
graphs:
•
Waveform of the reference signal
•
Waveform of the test signal
•
Front End Clipping region as a red shaded area
•
Hold Over Time region as a yellow shaded area
•
Drop outs as an orange shaded area
All waveforms can be shown before or after the time and level alignment and in
dBov as well as linear.
Additional information is shown on the right side of the diagram. This
information includes the time and date of the measurement, as well as general
information on the input data. The delay shown is the average delay in
milliseconds as well as in samples. This delay is the average for the entire
measurement period.
B A N D V O I C E Q U A L I T Y
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Figure