HP 85106D, Manual

Page: 62 / 244

HP 85106D mm-Wave System 2-17
Operation
Measurement System Calibration
Measurement System Calibration
A perfect vector network analyzer exhibits flat frequency response, no
impedance mismatches, and infinite isolation between channels. In an actual
system all of these characteristics are imperfect, but are generally repeatable
and predictable. To correct for these systematic errors, measurement
calibration is performed using known impedance standards connected at the
measurement ports. All of the required standards are supplied with the
HP 11644A series calibration kits. To be sure the system is meeting
measurement specifications, refer to Chapter 3, “Performance Verification”.
The HP 85106D with an HP 11644A series calibration kit can use any of the
accuracy enhancement models available with the HP 8510C. For
measurement of 2-port devices use, Full 2-Port, TRL 2-Port, or a
combination of Transmission Response and Reflection 2-Port calibrations.
Refer to the standard HP 8510C Operating and Programming manual and to
the calibration kit manual for descriptions of the calibration types.
Procedures for the TRL 2-Port, Response, Response & Isolation, and 1-Port
calibration types are described in this section.
Warm-up Time
Allow at least one hour for the system to reach a stable temperature after
power is turned on before trying to get highly repeatable measurements. In
addition, a stable ambient temperature helps to minimize time-base
variations, as well as physical dimensional changes that appear as short or
long term drift in magnitude and phase measurements.
Before Starting a
Measurement
Calibration
Check to be certain the appropriate CAL KIT definition is installed in the
HP 8510C. This definition is part of the Machine Dump file previously
loaded, and is contained on the disk in each HP 11644A series calibration
kit. Press [
CAL
] and read the {
CAL 1
}or {
CAL 2
} softkey label to confirm the
calibration kit label.
Setting the Stimulus
Values
Set all of the desired Stimulus characteristics for device measurement. These
include the frequency range or frequency list, the number of points, Source
#1 power level, and so forth. If the DUT must be measured using different
stimulus settings, then make separate measurement calibrations for each
frequency range (except where the HP 8510C Frequency Subset feature can
be used).