Wavetek ANT-20, Руководство по эксплуатации

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Broadband Analyzer/Generator ANT-20/ANT-20E
O-36 Operation
5.9.5 Source parameters
The “Source Parameters” field is used to set the source parameters. These determine the load
conditions for the channel (Peak Cell Rate, Mean Cell Rate) and the jitter and burst
characteristics. When you select a test channel, the source parameters will be initialized with
the default values pre-defined in the “Channel Editor”.
Each source parameter has its own increment / decrement buttons for entering the parameters.
The units are selected from the adjacent list boxes.
The “Source Parameters” field consists of the following sections:
:
With regard to the generated cell rate, the traffic generator has a high resolution range (for low
cell rates) and a low resolution range (for high cell rates). If the low resolution range is active,
the arrow keys for the lowest value digit of the increment / decrement keypad are highlighted in
yellow.
The source parameters are interdependent, i.e. you cannot set a mean cell rate that is higher
than the peak cell rate. Cell jitter and burst size are limited by the characteristics of the traffic
generator. If a parameter value cannot be set as required, this may be due to the set values of
other parameters. It is a good idea to set the parameters in the following order:
•
Mean and peak cell rates
•
Burst size
•
Cell jitter
The maximum values for burst size and cell jitter are limited and depend on the settings of other
parameters. Where appropriate, the burst size and cell jitter settings will be reduced
automatically by the instrument.
Section Meaning
Peak Cell Rate Peak cell rate (load) in Mbps, kbps or cps (cells/s).
Mean Cell Rate
1
Mean cell rate (load) in Mbps, kbps or cps (cells/s).
Cell Jitter Cell jitter in ms or µs.
Burst Size
1
Burst size in ms or µs.
Shape to contract
2
Check box: Activate traffic shaper.
Set Default Push button: Sets the source parameters to the pre-defined values on the
“Traffic Source” (Channel Editor) index card.
Set Maximum
2
Push button: Sets the source parameters to their maximum possible values.
These are determined by the traffic contract.
1 Not always available; depends on source type
2 Not always available; depends on conformance definition
Table O-20 Source Parameters