WCDMA TPC Measurement
R&S
®
CMW-KG4xx/-KM4xx/-KS4xx
775
User Manual 1173.9657.02 ─ 11
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Other customer-specific applications:
Provide an external trigger signal fed in via TRIG A or TRIG B on the rear panel of
the instrument and select this trigger source "…External TRIG A/B".
For "Inner Loop Power Control" mode and "Monitor" mode, time the trigger event
so that it occurs one slot before the UL slot reflecting the reaction of the UE to the
first TPC command.
Example: If the first TPC bit is transferred in the first timeslot (slot 0) of a DL radio
frame, the reaction of the UE is expected in the first timeslot of the UL radio frame.
In that case the trigger event must occur at the beginning of the last timeslot (slot
14) of the previous UL radio frame.
For "Change of TFC" mode, align the trigger event to a slot or frame boundary.
For optimum measurement results and measurement speed, it is recommended to
select the trigger source according to these rules, even when using the monitor mode.
However, the "Free Run" and "IF Power" trigger sources can sometimes be suitable for
measurements in monitor mode. The effect of these trigger sources is as follows:
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Free Run (Standard / Fast Sync):
The measurement starts immediately after it is initiated. The R&S
CMW decodes
the signal to derive its slot timing so that the "Measurement Length" can start at a
slot boundary of the UL WCDMA signal.
The "Standard" and "Fast Sync" modes differ in the synchronization procedure per-
formed after each measurement cycle. As the TPC measurement is a single shot
application and performs only one measurement cycle, there is no difference
between the two modes.
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IF Power:
With an internal IF power trigger, the measurement is triggered by the power ramp
of the received bursts. This trigger can be used if no continuous WCDMA signal is
available and a short signal burst has to be measured.
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IF Power (Sync):
Similar to "IF Power", however, the R&S
CMW tries to synchronize to the signal
during a full slot after the trigger event. This setting can be used to measure short
signal bursts where the beginning of the burst does not exactly coincide with a slot
boundary. The start of the measurement takes longer than with "IF Power".
chapter 4.3.2.4, "Trigger Settings"
4.2.5 TPC Setups
The WCDMA generator and the WCDMA signaling application provide several prede-
fined and partly configurable TPC setups with different TPC command patterns. This
section provides an overview of these TPC setups from point of view of the TPC mea-
surement. For more details concerning the individual TPC setups please refer to the
description of the corresponding application.
The used measurement mode depends directly on the selected TPC setup.
General Description
深圳德标仪器
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