Agilent Technologies 83236B, Руководство по эксплуатации, Страница: 72 / 164

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Chapter 3, Programming the PCS Interface using GPIB Control
Overview of Programming Issues
Power Detector,
Triggering Types,
and Power
Measurements
The power detector
The PCS Interface has a built-in detector for direct power measurements of the
UUT’s transmitter signals connected to the RF IN/OUT port.
Triggering types
Trigger and data collection features have been included to provide direct power
measurements of continuous wave (CW), TDMA, and continuous CDMA
signals. Three triggering types are available.
• Immediate trigger
• Internal amplitude trigger
• External trigger
Detailed procedures for setting trigger types and data collection conditions are
discussed later in this chapter.
Power measurements
After the UUT’s transmitter signal is applied to the RF IN/OUT port and the
desired trigger and data collection conditions are set in the PCS Interface, the
power measurement is performed using an GPIB query. When the query
command is received, the PCS Interface’s CPU collects power measurement
samples from the internal detector, selects the appropriate data, calculates the
resulting power, then returns the result over GPIB.
The power calculation performed by the PCS Interface’s CPU includes two
correction factors, frequency drift and dc drift correction factors which are
established during factory calibration. To assure that the correct factors are
applied, the desired UUT transmitter frequency should be set in the PCS Interface
and the dc offset compensation should be performed
before making the power
measurement.