Technical data

562 Chapter 19
W-CDMA or W-CDMA (with HSDPA) Analyzer
W-CDMA or W-CDMA (with HSDPA) Analyzer Measurement Settings
W-CDMA or W-CDMA (with HSDPA)
Analyzer
Setting the Active Channel Threshold Level and Auto Threshold
Level
The active channel threshold level is an advanced setting that can be set to indicate
which code channels are considered active. Any code channels exceeding this power
level are considered active traffic channels and any code channels below this power
level are considered inactive (or noise). Those channels that are considered active,
that is, channels that meet or exceed the threshold level, are indicated by the
presence of their OVSF Code below the bar in the display. Inactive channels do not
have their OVSF Codes displayed.
A horizontal red line on the screen represents the threshold. The test set can set this
level automatically, or you can manually enter a value.
In Auto mode the threshold level moves as the noise fluctuates. The threshold level
is set by the test set at an optimal offset above the average noise floor. In Auto mode,
you can alter the Auto Threshold Offset. The recommended and default setting is
0 dB. A negative value moves the threshold lower (closer to the noise floor) and is a
more aggressive setting that increases the likelihood of interpreting an inactive
channel as active. A positive value moves the threshold higher (away from the noise
floor) and is a more conservative setting that increases the likelihood of interpreting
an active channel as inactive.
In Manual mode the threshold level is fixed and does not move as the noise
fluctuates.
Setting the active channel threshold level:
2 [Restart] This key is unavailable or has no effect when
Sweep is set to Single. To restart a Single
Sweep measurement, press [Single].
Step Notes
1 [Setup]
2 On [Threshold] select
Auto or Manual.
Each time you press this softkey, the selected option
changes. If you choose Manual, you must enter the
threshold you want using the numeric keypad, then
press [dB].
Step Notes